/*- * Copyright (c) 2016-2020 Netflix, Inc. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * */ #include #include "opt_inet.h" #include "opt_inet6.h" #include "opt_ipsec.h" #include "opt_ratelimit.h" #include "opt_kern_tls.h" #if defined(INET) || defined(INET6) #include #include #include #include #ifdef TCP_HHOOK #include #endif #include #include #include #include #include #include /* for proc0 declaration */ #include #include #include #include #ifdef STATS #include #include #include /* Must come after qmath.h and tree.h */ #else #include #endif #include #include #include #include #include #include #include #ifdef TCP_ACCOUNTING #include #include #endif #include #include #include #include #define TCPSTATES /* for logging */ #include #include #include #include #include /* required for icmp_var.h */ #include /* for ICMP_BANDLIM */ #include #include #include #include #include #define TCPOUTFLAGS #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef NETFLIX_SHARED_CWND #include #endif #ifdef TCP_OFFLOAD #include #endif #ifdef INET6 #include #endif #include #include #if defined(IPSEC) || defined(IPSEC_SUPPORT) #include #include #endif /* IPSEC */ #include #include #include #ifdef MAC #include #endif #include "sack_filter.h" #include "tcp_rack.h" #include "tailq_hash.h" #include "rack_bbr_common.h" uma_zone_t rack_zone; uma_zone_t rack_pcb_zone; #ifndef TICKS2SBT #define TICKS2SBT(__t) (tick_sbt * ((sbintime_t)(__t))) #endif VNET_DECLARE(uint32_t, newreno_beta); VNET_DECLARE(uint32_t, newreno_beta_ecn); #define V_newreno_beta VNET(newreno_beta) #define V_newreno_beta_ecn VNET(newreno_beta_ecn) MALLOC_DEFINE(M_TCPFSB, "tcp_fsb", "TCP fast send block"); MALLOC_DEFINE(M_TCPDO, "tcp_do", "TCP deferred options"); struct sysctl_ctx_list rack_sysctl_ctx; struct sysctl_oid *rack_sysctl_root; #define CUM_ACKED 1 #define SACKED 2 /* * The RACK module incorporates a number of * TCP ideas that have been put out into the IETF * over the last few years: * - Matt Mathis's Rate Halving which slowly drops * the congestion window so that the ack clock can * be maintained during a recovery. * - Yuchung Cheng's RACK TCP (for which its named) that * will stop us using the number of dup acks and instead * use time as the gage of when we retransmit. * - Reorder Detection of RFC4737 and the Tail-Loss probe draft * of Dukkipati et.al. * RACK depends on SACK, so if an endpoint arrives that * cannot do SACK the state machine below will shuttle the * connection back to using the "default" TCP stack that is * in FreeBSD. * * To implement RACK the original TCP stack was first decomposed * into a functional state machine with individual states * for each of the possible TCP connection states. The do_segment * functions role in life is to mandate the connection supports SACK * initially and then assure that the RACK state matches the conenction * state before calling the states do_segment function. Each * state is simplified due to the fact that the original do_segment * has been decomposed and we *know* what state we are in (no * switches on the state) and all tests for SACK are gone. This * greatly simplifies what each state does. * * TCP output is also over-written with a new version since it * must maintain the new rack scoreboard. * */ static int32_t rack_tlp_thresh = 1; static int32_t rack_tlp_limit = 2; /* No more than 2 TLPs w-out new data */ static int32_t rack_tlp_use_greater = 1; static int32_t rack_reorder_thresh = 2; static int32_t rack_reorder_fade = 60000000; /* 0 - never fade, def 60,000,000 * - 60 seconds */ static uint32_t rack_clamp_ss_upper = 110; static uint32_t rack_clamp_ca_upper = 105; static uint32_t rack_rxt_min_rnds = 10; /* Min rounds if drastic rxt clamp is in place */ static uint32_t rack_unclamp_round_thresh = 100; /* number of perfect rounds before we unclamp */ static uint32_t rack_unclamp_rxt_thresh = 5; /* .5% and under */ static uint64_t rack_rxt_clamp_thresh = 0; /* Do we do the rxt clamp thing */ static int32_t rack_dnd_default = 0; /* For rr_conf = 3, what is the default for dnd */ static int32_t rack_rxt_controls = 0; static int32_t rack_fill_cw_state = 0; static uint8_t rack_req_measurements = 1; /* Attack threshold detections */ static uint32_t rack_highest_sack_thresh_seen = 0; static uint32_t rack_highest_move_thresh_seen = 0; static uint32_t rack_merge_out_sacks_on_attack = 0; static int32_t rack_enable_hw_pacing = 0; /* Due to CCSP keep it off by default */ static int32_t rack_hw_pace_extra_slots = 0; /* 2 extra MSS time betweens */ static int32_t rack_hw_rate_caps = 0; /* 1; */ static int32_t rack_hw_rate_cap_per = 0; /* 0 -- off */ static int32_t rack_hw_rate_min = 0; /* 1500000;*/ static int32_t rack_hw_rate_to_low = 0; /* 1200000; */ static int32_t rack_hw_up_only = 0; static int32_t rack_stats_gets_ms_rtt = 1; static int32_t rack_prr_addbackmax = 2; static int32_t rack_do_hystart = 0; static int32_t rack_apply_rtt_with_reduced_conf = 0; static int32_t rack_hibeta_setting = 0; static int32_t rack_default_pacing_divisor = 250; static int32_t rack_uses_full_dgp_in_rec = 1; static uint16_t rack_pacing_min_seg = 0; static uint32_t sad_seg_size_per = 800; /* 80.0 % */ static int32_t rack_pkt_delay = 1000; static int32_t rack_send_a_lot_in_prr = 1; static int32_t rack_min_to = 1000; /* Number of microsecond min timeout */ static int32_t rack_verbose_logging = 0; static int32_t rack_ignore_data_after_close = 1; static int32_t rack_enable_shared_cwnd = 1; static int32_t rack_use_cmp_acks = 1; static int32_t rack_use_fsb = 1; static int32_t rack_use_rfo = 1; static int32_t rack_use_rsm_rfo = 1; static int32_t rack_max_abc_post_recovery = 2; static int32_t rack_client_low_buf = 0; static int32_t rack_dsack_std_based = 0x3; /* bit field bit 1 sets rc_rack_tmr_std_based and bit 2 sets rc_rack_use_dsack */ static int32_t rack_bw_multipler = 2; /* Limit on fill cw's jump up to be this x gp_est */ #ifdef TCP_ACCOUNTING static int32_t rack_tcp_accounting = 0; #endif static int32_t rack_limits_scwnd = 1; static int32_t rack_enable_mqueue_for_nonpaced = 0; static int32_t rack_hybrid_allow_set_maxseg = 0; static int32_t rack_disable_prr = 0; static int32_t use_rack_rr = 1; static int32_t rack_non_rxt_use_cr = 0; /* does a non-rxt in recovery use the configured rate (ss/ca)? */ static int32_t rack_persist_min = 250000; /* 250usec */ static int32_t rack_persist_max = 2000000; /* 2 Second in usec's */ static int32_t rack_sack_not_required = 1; /* set to one to allow non-sack to use rack */ static int32_t rack_default_init_window = 0; /* Use system default */ static int32_t rack_limit_time_with_srtt = 0; static int32_t rack_autosndbuf_inc = 20; /* In percentage form */ static int32_t rack_enobuf_hw_boost_mult = 0; /* How many times the hw rate we boost slot using time_between */ static int32_t rack_enobuf_hw_max = 12000; /* 12 ms in usecs */ static int32_t rack_enobuf_hw_min = 10000; /* 10 ms in usecs */ static int32_t rack_hw_rwnd_factor = 2; /* How many max_segs the rwnd must be before we hold off sending */ static int32_t rack_hw_check_queue = 0; /* Do we always pre-check queue depth of a hw queue */ static int32_t rack_full_buffer_discount = 10; /* * Currently regular tcp has a rto_min of 30ms * the backoff goes 12 times so that ends up * being a total of 122.850 seconds before a * connection is killed. */ static uint32_t rack_def_data_window = 20; static uint32_t rack_goal_bdp = 2; static uint32_t rack_min_srtts = 1; static uint32_t rack_min_measure_usec = 0; static int32_t rack_tlp_min = 10000; /* 10ms */ static int32_t rack_rto_min = 30000; /* 30,000 usec same as main freebsd */ static int32_t rack_rto_max = 4000000; /* 4 seconds in usec's */ static const int32_t rack_free_cache = 2; static int32_t rack_hptsi_segments = 40; static int32_t rack_rate_sample_method = USE_RTT_LOW; static int32_t rack_pace_every_seg = 0; static int32_t rack_delayed_ack_time = 40000; /* 40ms in usecs */ static int32_t rack_slot_reduction = 4; static int32_t rack_wma_divisor = 8; /* For WMA calculation */ static int32_t rack_cwnd_block_ends_measure = 0; static int32_t rack_rwnd_block_ends_measure = 0; static int32_t rack_def_profile = 0; static int32_t rack_lower_cwnd_at_tlp = 0; static int32_t rack_limited_retran = 0; static int32_t rack_always_send_oldest = 0; static int32_t rack_tlp_threshold_use = TLP_USE_TWO_ONE; static uint16_t rack_per_of_gp_ss = 250; /* 250 % slow-start */ static uint16_t rack_per_of_gp_ca = 200; /* 200 % congestion-avoidance */ static uint16_t rack_per_of_gp_rec = 200; /* 200 % of bw */ /* Probertt */ static uint16_t rack_per_of_gp_probertt = 60; /* 60% of bw */ static uint16_t rack_per_of_gp_lowthresh = 40; /* 40% is bottom */ static uint16_t rack_per_of_gp_probertt_reduce = 10; /* 10% reduction */ static uint16_t rack_atexit_prtt_hbp = 130; /* Clamp to 130% on exit prtt if highly buffered path */ static uint16_t rack_atexit_prtt = 130; /* Clamp to 100% on exit prtt if non highly buffered path */ static uint32_t rack_max_drain_wait = 2; /* How man gp srtt's before we give up draining */ static uint32_t rack_must_drain = 1; /* How many GP srtt's we *must* wait */ static uint32_t rack_probertt_use_min_rtt_entry = 1; /* Use the min to calculate the goal else gp_srtt */ static uint32_t rack_probertt_use_min_rtt_exit = 0; static uint32_t rack_probe_rtt_sets_cwnd = 0; static uint32_t rack_probe_rtt_safety_val = 2000000; /* No more than 2 sec in probe-rtt */ static uint32_t rack_time_between_probertt = 9600000; /* 9.6 sec in usecs */ static uint32_t rack_probertt_gpsrtt_cnt_mul = 0; /* How many srtt periods does probe-rtt last top fraction */ static uint32_t rack_probertt_gpsrtt_cnt_div = 0; /* How many srtt periods does probe-rtt last bottom fraction */ static uint32_t rack_min_probertt_hold = 40000; /* Equal to delayed ack time */ static uint32_t rack_probertt_filter_life = 10000000; static uint32_t rack_probertt_lower_within = 10; static uint32_t rack_min_rtt_movement = 250000; /* Must move at least 250ms (in microseconds) to count as a lowering */ static int32_t rack_pace_one_seg = 0; /* Shall we pace for less than 1.4Meg 1MSS at a time */ static int32_t rack_probertt_clear_is = 1; static int32_t rack_max_drain_hbp = 1; /* Extra drain times gpsrtt for highly buffered paths */ static int32_t rack_hbp_thresh = 3; /* what is the divisor max_rtt/min_rtt to decided a hbp */ /* Part of pacing */ static int32_t rack_max_per_above = 30; /* When we go to increment stop if above 100+this% */ /* Timely information: * * Here we have various control parameters on how * timely may change the multiplier. rack_gain_p5_ub * is associated with timely but not directly influencing * the rate decision like the other variables. It controls * the way fill-cw interacts with timely and caps how much * timely can boost the fill-cw b/w. * * The other values are various boost/shrink numbers as well * as potential caps when adjustments are made to the timely * gain (returned by rack_get_output_gain(). Remember too that * the gain returned can be overriden by other factors such as * probeRTT as well as fixed-rate-pacing. */ static int32_t rack_gain_p5_ub = 250; static int32_t rack_gp_per_bw_mul_up = 2; /* 2% */ static int32_t rack_gp_per_bw_mul_down = 4; /* 4% */ static int32_t rack_gp_rtt_maxmul = 3; /* 3 x maxmin */ static int32_t rack_gp_rtt_minmul = 1; /* minrtt + (minrtt/mindiv) is lower rtt */ static int32_t rack_gp_rtt_mindiv = 4; /* minrtt + (minrtt * minmul/mindiv) is lower rtt */ static int32_t rack_gp_decrease_per = 80; /* Beta value of timely decrease (.8) = 80 */ static int32_t rack_gp_increase_per = 2; /* 2% increase in multiplier */ static int32_t rack_per_lower_bound = 50; /* Don't allow to drop below this multiplier */ static int32_t rack_per_upper_bound_ss = 0; /* Don't allow SS to grow above this */ static int32_t rack_per_upper_bound_ca = 0; /* Don't allow CA to grow above this */ static int32_t rack_do_dyn_mul = 0; /* Are the rack gp multipliers dynamic */ static int32_t rack_gp_no_rec_chg = 1; /* Prohibit recovery from reducing it's multiplier */ static int32_t rack_timely_dec_clear = 6; /* Do we clear decrement count at a value (6)? */ static int32_t rack_timely_max_push_rise = 3; /* One round of pushing */ static int32_t rack_timely_max_push_drop = 3; /* Three round of pushing */ static int32_t rack_timely_min_segs = 4; /* 4 segment minimum */ static int32_t rack_use_max_for_nobackoff = 0; static int32_t rack_timely_int_timely_only = 0; /* do interim timely's only use the timely algo (no b/w changes)? */ static int32_t rack_timely_no_stopping = 0; static int32_t rack_down_raise_thresh = 100; static int32_t rack_req_segs = 1; static uint64_t rack_bw_rate_cap = 0; /* Rack specific counters */ counter_u64_t rack_saw_enobuf; counter_u64_t rack_saw_enobuf_hw; counter_u64_t rack_saw_enetunreach; counter_u64_t rack_persists_sends; counter_u64_t rack_persists_acks; counter_u64_t rack_persists_loss; counter_u64_t rack_persists_lost_ends; counter_u64_t rack_total_bytes; #ifdef INVARIANTS counter_u64_t rack_adjust_map_bw; #endif /* Tail loss probe counters */ counter_u64_t rack_tlp_tot; counter_u64_t rack_tlp_newdata; counter_u64_t rack_tlp_retran; counter_u64_t rack_tlp_retran_bytes; counter_u64_t rack_to_tot; counter_u64_t rack_hot_alloc; counter_u64_t rack_to_alloc; counter_u64_t rack_to_alloc_hard; counter_u64_t rack_to_alloc_emerg; counter_u64_t rack_to_alloc_limited; counter_u64_t rack_alloc_limited_conns; counter_u64_t rack_split_limited; counter_u64_t rack_rxt_clamps_cwnd; counter_u64_t rack_rxt_clamps_cwnd_uniq; counter_u64_t rack_multi_single_eq; counter_u64_t rack_proc_non_comp_ack; counter_u64_t rack_fto_send; counter_u64_t rack_fto_rsm_send; counter_u64_t rack_nfto_resend; counter_u64_t rack_non_fto_send; counter_u64_t rack_extended_rfo; counter_u64_t rack_sack_proc_all; counter_u64_t rack_sack_proc_short; counter_u64_t rack_sack_proc_restart; counter_u64_t rack_sack_attacks_detected; counter_u64_t rack_sack_attacks_reversed; counter_u64_t rack_sack_attacks_suspect; counter_u64_t rack_sack_used_next_merge; counter_u64_t rack_sack_splits; counter_u64_t rack_sack_used_prev_merge; counter_u64_t rack_sack_skipped_acked; counter_u64_t rack_ack_total; counter_u64_t rack_express_sack; counter_u64_t rack_sack_total; counter_u64_t rack_move_none; counter_u64_t rack_move_some; counter_u64_t rack_input_idle_reduces; counter_u64_t rack_collapsed_win; counter_u64_t rack_collapsed_win_seen; counter_u64_t rack_collapsed_win_rxt; counter_u64_t rack_collapsed_win_rxt_bytes; counter_u64_t rack_try_scwnd; counter_u64_t rack_hw_pace_init_fail; counter_u64_t rack_hw_pace_lost; counter_u64_t rack_out_size[TCP_MSS_ACCT_SIZE]; counter_u64_t rack_opts_arry[RACK_OPTS_SIZE]; #define RACK_REXMTVAL(tp) max(rack_rto_min, ((tp)->t_srtt + ((tp)->t_rttvar << 2))) #define RACK_TCPT_RANGESET(tv, value, tvmin, tvmax, slop) do { \ (tv) = (value) + slop; \ if ((u_long)(tv) < (u_long)(tvmin)) \ (tv) = (tvmin); \ if ((u_long)(tv) > (u_long)(tvmax)) \ (tv) = (tvmax); \ } while (0) static void rack_log_progress_event(struct tcp_rack *rack, struct tcpcb *tp, uint32_t tick, int event, int line); static int rack_process_ack(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, struct tcpopt *to, uint32_t tiwin, int32_t tlen, int32_t * ofia, int32_t thflags, int32_t * ret_val); static int rack_process_data(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, int32_t drop_hdrlen, int32_t tlen, uint32_t tiwin, int32_t thflags, int32_t nxt_pkt); static void rack_ack_received(struct tcpcb *tp, struct tcp_rack *rack, uint32_t th_ack, uint16_t nsegs, uint16_t type, int32_t recovery); static struct rack_sendmap *rack_alloc(struct tcp_rack *rack); static struct rack_sendmap *rack_alloc_limit(struct tcp_rack *rack, uint8_t limit_type); static struct rack_sendmap * rack_check_recovery_mode(struct tcpcb *tp, uint32_t tsused); static void rack_cong_signal(struct tcpcb *tp, uint32_t type, uint32_t ack, int ); static void rack_counter_destroy(void); static int rack_ctloutput(struct tcpcb *tp, struct sockopt *sopt); static int32_t rack_ctor(void *mem, int32_t size, void *arg, int32_t how); static void rack_set_pace_segments(struct tcpcb *tp, struct tcp_rack *rack, uint32_t line, uint64_t *fill_override); static void rack_do_segment(struct tcpcb *tp, struct mbuf *m, struct tcphdr *th, int32_t drop_hdrlen, int32_t tlen, uint8_t iptos); static void rack_dtor(void *mem, int32_t size, void *arg); static void rack_log_alt_to_to_cancel(struct tcp_rack *rack, uint32_t flex1, uint32_t flex2, uint32_t flex3, uint32_t flex4, uint32_t flex5, uint32_t flex6, uint16_t flex7, uint8_t mod); static void rack_log_pacing_delay_calc(struct tcp_rack *rack, uint32_t len, uint32_t slot, uint64_t bw_est, uint64_t bw, uint64_t len_time, int method, int line, struct rack_sendmap *rsm, uint8_t quality); static struct rack_sendmap * rack_find_high_nonack(struct tcp_rack *rack, struct rack_sendmap *rsm); static struct rack_sendmap *rack_find_lowest_rsm(struct tcp_rack *rack); static void rack_free(struct tcp_rack *rack, struct rack_sendmap *rsm); static void rack_fini(struct tcpcb *tp, int32_t tcb_is_purged); static int rack_get_sockopt(struct tcpcb *tp, struct sockopt *sopt); static void rack_do_goodput_measurement(struct tcpcb *tp, struct tcp_rack *rack, tcp_seq th_ack, int line, uint8_t quality); static void rack_log_type_pacing_sizes(struct tcpcb *tp, struct tcp_rack *rack, uint32_t arg1, uint32_t arg2, uint32_t arg3, uint8_t frm); static uint32_t rack_get_pacing_len(struct tcp_rack *rack, uint64_t bw, uint32_t mss); static int32_t rack_handoff_ok(struct tcpcb *tp); static int32_t rack_init(struct tcpcb *tp, void **ptr); static void rack_init_sysctls(void); static void rack_log_ack(struct tcpcb *tp, struct tcpopt *to, struct tcphdr *th, int entered_rec, int dup_ack_struck, int *dsack_seen, int *sacks_seen); static void rack_log_output(struct tcpcb *tp, struct tcpopt *to, int32_t len, uint32_t seq_out, uint16_t th_flags, int32_t err, uint64_t ts, struct rack_sendmap *hintrsm, uint16_t add_flags, struct mbuf *s_mb, uint32_t s_moff, int hw_tls, int segsiz); static uint64_t rack_get_gp_est(struct tcp_rack *rack); static void rack_log_sack_passed(struct tcpcb *tp, struct tcp_rack *rack, struct rack_sendmap *rsm); static void rack_log_to_event(struct tcp_rack *rack, int32_t to_num, struct rack_sendmap *rsm); static int32_t rack_output(struct tcpcb *tp); static uint32_t rack_proc_sack_blk(struct tcpcb *tp, struct tcp_rack *rack, struct sackblk *sack, struct tcpopt *to, struct rack_sendmap **prsm, uint32_t cts, int *no_extra, int *moved_two, uint32_t segsiz); static void rack_post_recovery(struct tcpcb *tp, uint32_t th_seq); static void rack_remxt_tmr(struct tcpcb *tp); static int rack_set_sockopt(struct tcpcb *tp, struct sockopt *sopt); static void rack_set_state(struct tcpcb *tp, struct tcp_rack *rack); static int32_t rack_stopall(struct tcpcb *tp); static void rack_timer_cancel(struct tcpcb *tp, struct tcp_rack *rack, uint32_t cts, int line); static uint32_t rack_update_entry(struct tcpcb *tp, struct tcp_rack *rack, struct rack_sendmap *rsm, uint64_t ts, int32_t * lenp, uint16_t add_flag, int segsiz); static void rack_update_rsm(struct tcpcb *tp, struct tcp_rack *rack, struct rack_sendmap *rsm, uint64_t ts, uint16_t add_flag, int segsiz); static int rack_update_rtt(struct tcpcb *tp, struct tcp_rack *rack, struct rack_sendmap *rsm, struct tcpopt *to, uint32_t cts, int32_t ack_type, tcp_seq th_ack); static int32_t tcp_addrack(module_t mod, int32_t type, void *data); static int rack_do_close_wait(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos); static int rack_do_closing(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos); static int rack_do_established(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos); static int rack_do_fastnewdata(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, uint32_t tiwin, int32_t nxt_pkt, uint8_t iptos); static int rack_do_fin_wait_1(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos); static int rack_do_fin_wait_2(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos); static int rack_do_lastack(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos); static int rack_do_syn_recv(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos); static int rack_do_syn_sent(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos); static void rack_chk_req_and_hybrid_on_out(struct tcp_rack *rack, tcp_seq seq, uint32_t len, uint64_t cts); struct rack_sendmap * tcp_rack_output(struct tcpcb *tp, struct tcp_rack *rack, uint32_t tsused); static void tcp_rack_xmit_timer(struct tcp_rack *rack, int32_t rtt, uint32_t len, uint32_t us_tim, int confidence, struct rack_sendmap *rsm, uint16_t rtrcnt); static void tcp_rack_partialack(struct tcpcb *tp); static int rack_set_profile(struct tcp_rack *rack, int prof); static void rack_apply_deferred_options(struct tcp_rack *rack); int32_t rack_clear_counter=0; static uint64_t rack_get_lt_bw(struct tcp_rack *rack) { struct timeval tv; uint64_t tim, bytes; tim = rack->r_ctl.lt_bw_time; bytes = rack->r_ctl.lt_bw_bytes; if (rack->lt_bw_up) { /* Include all the current bytes too */ microuptime(&tv); bytes += (rack->rc_tp->snd_una - rack->r_ctl.lt_seq); tim += (tcp_tv_to_lusectick(&tv) - rack->r_ctl.lt_timemark); } if ((bytes != 0) && (tim != 0)) return ((bytes * (uint64_t)1000000) / tim); else return (0); } static void rack_swap_beta_values(struct tcp_rack *rack, uint8_t flex8) { struct sockopt sopt; struct cc_newreno_opts opt; struct newreno old; struct tcpcb *tp; int error, failed = 0; tp = rack->rc_tp; if (tp->t_cc == NULL) { /* Tcb is leaving */ return; } rack->rc_pacing_cc_set = 1; if (strcmp(tp->t_cc->name, CCALGONAME_NEWRENO) != 0) { /* Not new-reno we can't play games with beta! */ failed = 1; goto out; } if (CC_ALGO(tp)->ctl_output == NULL) { /* Huh, not using new-reno so no swaps.? */ failed = 2; goto out; } /* Get the current values out */ sopt.sopt_valsize = sizeof(struct cc_newreno_opts); sopt.sopt_dir = SOPT_GET; opt.name = CC_NEWRENO_BETA; error = CC_ALGO(tp)->ctl_output(&tp->t_ccv, &sopt, &opt); if (error) { failed = 3; goto out; } old.beta = opt.val; opt.name = CC_NEWRENO_BETA_ECN; error = CC_ALGO(tp)->ctl_output(&tp->t_ccv, &sopt, &opt); if (error) { failed = 4; goto out; } old.beta_ecn = opt.val; /* Now lets set in the values we have stored */ sopt.sopt_dir = SOPT_SET; opt.name = CC_NEWRENO_BETA; opt.val = rack->r_ctl.rc_saved_beta.beta; error = CC_ALGO(tp)->ctl_output(&tp->t_ccv, &sopt, &opt); if (error) { failed = 5; goto out; } opt.name = CC_NEWRENO_BETA_ECN; opt.val = rack->r_ctl.rc_saved_beta.beta_ecn; error = CC_ALGO(tp)->ctl_output(&tp->t_ccv, &sopt, &opt); if (error) { failed = 6; goto out; } /* Save off the values for restoral */ memcpy(&rack->r_ctl.rc_saved_beta, &old, sizeof(struct newreno)); out: if (rack_verbose_logging && tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; struct newreno *ptr; ptr = ((struct newreno *)tp->t_ccv.cc_data); memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.flex1 = ptr->beta; log.u_bbr.flex2 = ptr->beta_ecn; log.u_bbr.flex3 = ptr->newreno_flags; log.u_bbr.flex4 = rack->r_ctl.rc_saved_beta.beta; log.u_bbr.flex5 = rack->r_ctl.rc_saved_beta.beta_ecn; log.u_bbr.flex6 = failed; log.u_bbr.flex7 = rack->gp_ready; log.u_bbr.flex7 <<= 1; log.u_bbr.flex7 |= rack->use_fixed_rate; log.u_bbr.flex7 <<= 1; log.u_bbr.flex7 |= rack->rc_pacing_cc_set; log.u_bbr.pkts_out = rack->r_ctl.rc_prr_sndcnt; log.u_bbr.flex8 = flex8; tcp_log_event(tp, NULL, NULL, NULL, BBR_LOG_CWND, error, 0, &log, false, NULL, NULL, 0, &tv); } } static void rack_set_cc_pacing(struct tcp_rack *rack) { if (rack->rc_pacing_cc_set) return; /* * Use the swap utility placing in 3 for flex8 to id a * set of a new set of values. */ rack->rc_pacing_cc_set = 1; rack_swap_beta_values(rack, 3); } static void rack_undo_cc_pacing(struct tcp_rack *rack) { if (rack->rc_pacing_cc_set == 0) return; /* * Use the swap utility placing in 4 for flex8 to id a * restoral of the old values. */ rack->rc_pacing_cc_set = 0; rack_swap_beta_values(rack, 4); } static void rack_log_gpset(struct tcp_rack *rack, uint32_t seq_end, uint32_t ack_end_t, uint32_t send_end_t, int line, uint8_t mode, struct rack_sendmap *rsm) { if (tcp_bblogging_on(rack->rc_tp) && (rack_verbose_logging != 0)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log, 0, sizeof(log)); log.u_bbr.flex1 = seq_end; log.u_bbr.flex2 = rack->rc_tp->gput_seq; log.u_bbr.flex3 = ack_end_t; log.u_bbr.flex4 = rack->rc_tp->gput_ts; log.u_bbr.flex5 = send_end_t; log.u_bbr.flex6 = rack->rc_tp->gput_ack; log.u_bbr.flex7 = mode; log.u_bbr.flex8 = 69; log.u_bbr.rttProp = rack->r_ctl.rc_gp_cumack_ts; log.u_bbr.delRate = rack->r_ctl.rc_gp_output_ts; log.u_bbr.pkts_out = line; log.u_bbr.cwnd_gain = rack->app_limited_needs_set; log.u_bbr.pkt_epoch = rack->r_ctl.rc_app_limited_cnt; if (rsm != NULL) { log.u_bbr.applimited = rsm->r_start; log.u_bbr.delivered = rsm->r_end; log.u_bbr.epoch = rsm->r_flags; } log.u_bbr.timeStamp = tcp_get_usecs(&tv); TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, BBR_LOG_HPTSI_CALC, 0, 0, &log, false, &tv); } } static int sysctl_rack_clear(SYSCTL_HANDLER_ARGS) { uint32_t stat; int32_t error; error = SYSCTL_OUT(req, &rack_clear_counter, sizeof(uint32_t)); if (error || req->newptr == NULL) return error; error = SYSCTL_IN(req, &stat, sizeof(uint32_t)); if (error) return (error); if (stat == 1) { #ifdef INVARIANTS printf("Clearing RACK counters\n"); #endif counter_u64_zero(rack_tlp_tot); counter_u64_zero(rack_tlp_newdata); counter_u64_zero(rack_tlp_retran); counter_u64_zero(rack_tlp_retran_bytes); counter_u64_zero(rack_to_tot); counter_u64_zero(rack_saw_enobuf); counter_u64_zero(rack_saw_enobuf_hw); counter_u64_zero(rack_saw_enetunreach); counter_u64_zero(rack_persists_sends); counter_u64_zero(rack_total_bytes); counter_u64_zero(rack_persists_acks); counter_u64_zero(rack_persists_loss); counter_u64_zero(rack_persists_lost_ends); #ifdef INVARIANTS counter_u64_zero(rack_adjust_map_bw); #endif counter_u64_zero(rack_to_alloc_hard); counter_u64_zero(rack_to_alloc_emerg); counter_u64_zero(rack_sack_proc_all); counter_u64_zero(rack_fto_send); counter_u64_zero(rack_fto_rsm_send); counter_u64_zero(rack_extended_rfo); counter_u64_zero(rack_hw_pace_init_fail); counter_u64_zero(rack_hw_pace_lost); counter_u64_zero(rack_non_fto_send); counter_u64_zero(rack_nfto_resend); counter_u64_zero(rack_sack_proc_short); counter_u64_zero(rack_sack_proc_restart); counter_u64_zero(rack_to_alloc); counter_u64_zero(rack_to_alloc_limited); counter_u64_zero(rack_alloc_limited_conns); counter_u64_zero(rack_split_limited); counter_u64_zero(rack_rxt_clamps_cwnd); counter_u64_zero(rack_rxt_clamps_cwnd_uniq); counter_u64_zero(rack_multi_single_eq); counter_u64_zero(rack_proc_non_comp_ack); counter_u64_zero(rack_sack_attacks_detected); counter_u64_zero(rack_sack_attacks_reversed); counter_u64_zero(rack_sack_attacks_suspect); counter_u64_zero(rack_sack_used_next_merge); counter_u64_zero(rack_sack_used_prev_merge); counter_u64_zero(rack_sack_splits); counter_u64_zero(rack_sack_skipped_acked); counter_u64_zero(rack_ack_total); counter_u64_zero(rack_express_sack); counter_u64_zero(rack_sack_total); counter_u64_zero(rack_move_none); counter_u64_zero(rack_move_some); counter_u64_zero(rack_try_scwnd); counter_u64_zero(rack_collapsed_win); counter_u64_zero(rack_collapsed_win_rxt); counter_u64_zero(rack_collapsed_win_seen); counter_u64_zero(rack_collapsed_win_rxt_bytes); } else if (stat == 2) { #ifdef INVARIANTS printf("Clearing RACK option array\n"); #endif COUNTER_ARRAY_ZERO(rack_opts_arry, RACK_OPTS_SIZE); } else if (stat == 3) { printf("Rack has no stats counters to clear (use 1 to clear all stats in sysctl node)\n"); } else if (stat == 4) { #ifdef INVARIANTS printf("Clearing RACK out size array\n"); #endif COUNTER_ARRAY_ZERO(rack_out_size, TCP_MSS_ACCT_SIZE); } rack_clear_counter = 0; return (0); } static void rack_init_sysctls(void) { struct sysctl_oid *rack_counters; struct sysctl_oid *rack_attack; struct sysctl_oid *rack_pacing; struct sysctl_oid *rack_timely; struct sysctl_oid *rack_timers; struct sysctl_oid *rack_tlp; struct sysctl_oid *rack_misc; struct sysctl_oid *rack_features; struct sysctl_oid *rack_measure; struct sysctl_oid *rack_probertt; struct sysctl_oid *rack_hw_pacing; rack_attack = SYSCTL_ADD_NODE(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_sysctl_root), OID_AUTO, "sack_attack", CTLFLAG_RW | CTLFLAG_MPSAFE, 0, "Rack Sack Attack Counters and Controls"); rack_counters = SYSCTL_ADD_NODE(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_sysctl_root), OID_AUTO, "stats", CTLFLAG_RW | CTLFLAG_MPSAFE, 0, "Rack Counters"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_sysctl_root), OID_AUTO, "rate_sample_method", CTLFLAG_RW, &rack_rate_sample_method , USE_RTT_LOW, "What method should we use for rate sampling 0=high, 1=low "); /* Probe rtt related controls */ rack_probertt = SYSCTL_ADD_NODE(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_sysctl_root), OID_AUTO, "probertt", CTLFLAG_RW | CTLFLAG_MPSAFE, 0, "ProbeRTT related Controls"); SYSCTL_ADD_U16(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_probertt), OID_AUTO, "exit_per_hpb", CTLFLAG_RW, &rack_atexit_prtt_hbp, 130, "What percentage above goodput do we clamp CA/SS to at exit on high-BDP path 110%"); SYSCTL_ADD_U16(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_probertt), OID_AUTO, "exit_per_nonhpb", CTLFLAG_RW, &rack_atexit_prtt, 130, "What percentage above goodput do we clamp CA/SS to at exit on a non high-BDP path 100%"); SYSCTL_ADD_U16(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_probertt), OID_AUTO, "gp_per_mul", CTLFLAG_RW, &rack_per_of_gp_probertt, 60, "What percentage of goodput do we pace at in probertt"); SYSCTL_ADD_U16(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_probertt), OID_AUTO, "gp_per_reduce", CTLFLAG_RW, &rack_per_of_gp_probertt_reduce, 10, "What percentage of goodput do we reduce every gp_srtt"); SYSCTL_ADD_U16(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_probertt), OID_AUTO, "gp_per_low", CTLFLAG_RW, &rack_per_of_gp_lowthresh, 40, "What percentage of goodput do we allow the multiplier to fall to"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_probertt), OID_AUTO, "time_between", CTLFLAG_RW, & rack_time_between_probertt, 96000000, "How many useconds between the lowest rtt falling must past before we enter probertt"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_probertt), OID_AUTO, "safety", CTLFLAG_RW, &rack_probe_rtt_safety_val, 2000000, "If not zero, provides a maximum usecond that you can stay in probertt (2sec = 2000000)"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_probertt), OID_AUTO, "sets_cwnd", CTLFLAG_RW, &rack_probe_rtt_sets_cwnd, 0, "Do we set the cwnd too (if always_lower is on)"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_probertt), OID_AUTO, "maxdrainsrtts", CTLFLAG_RW, &rack_max_drain_wait, 2, "Maximum number of gp_srtt's to hold in drain waiting for flight to reach goal"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_probertt), OID_AUTO, "mustdrainsrtts", CTLFLAG_RW, &rack_must_drain, 1, "We must drain this many gp_srtt's waiting for flight to reach goal"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_probertt), OID_AUTO, "goal_use_min_entry", CTLFLAG_RW, &rack_probertt_use_min_rtt_entry, 1, "Should we use the min-rtt to calculate the goal rtt (else gp_srtt) at entry"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_probertt), OID_AUTO, "goal_use_min_exit", CTLFLAG_RW, &rack_probertt_use_min_rtt_exit, 0, "How to set cwnd at exit, 0 - dynamic, 1 - use min-rtt, 2 - use curgprtt, 3 - entry gp-rtt"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_probertt), OID_AUTO, "length_div", CTLFLAG_RW, &rack_probertt_gpsrtt_cnt_div, 0, "How many recent goodput srtt periods plus hold tim does probertt last (bottom of fraction)"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_probertt), OID_AUTO, "length_mul", CTLFLAG_RW, &rack_probertt_gpsrtt_cnt_mul, 0, "How many recent goodput srtt periods plus hold tim does probertt last (top of fraction)"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_probertt), OID_AUTO, "holdtim_at_target", CTLFLAG_RW, &rack_min_probertt_hold, 200000, "What is the minimum time we hold probertt at target"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_probertt), OID_AUTO, "filter_life", CTLFLAG_RW, &rack_probertt_filter_life, 10000000, "What is the time for the filters life in useconds"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_probertt), OID_AUTO, "lower_within", CTLFLAG_RW, &rack_probertt_lower_within, 10, "If the rtt goes lower within this percentage of the time, go into probe-rtt"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_probertt), OID_AUTO, "must_move", CTLFLAG_RW, &rack_min_rtt_movement, 250, "How much is the minimum movement in rtt to count as a drop for probertt purposes"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_probertt), OID_AUTO, "clear_is_cnts", CTLFLAG_RW, &rack_probertt_clear_is, 1, "Do we clear I/S counts on exiting probe-rtt"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_probertt), OID_AUTO, "hbp_extra_drain", CTLFLAG_RW, &rack_max_drain_hbp, 1, "How many extra drain gpsrtt's do we get in highly buffered paths"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_probertt), OID_AUTO, "hbp_threshold", CTLFLAG_RW, &rack_hbp_thresh, 3, "We are highly buffered if min_rtt_seen / max_rtt_seen > this-threshold"); /* Pacing related sysctls */ rack_pacing = SYSCTL_ADD_NODE(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_sysctl_root), OID_AUTO, "pacing", CTLFLAG_RW | CTLFLAG_MPSAFE, 0, "Pacing related Controls"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_pacing), OID_AUTO, "fulldgpinrec", CTLFLAG_RW, &rack_uses_full_dgp_in_rec, 1, "Do we use all DGP features in recovery (fillcw, timely et.al.)?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_pacing), OID_AUTO, "fullbufdisc", CTLFLAG_RW, &rack_full_buffer_discount, 10, "What percentage b/w reduction over the GP estimate for a full buffer (default=0 off)?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_pacing), OID_AUTO, "fillcw", CTLFLAG_RW, &rack_fill_cw_state, 0, "Enable fillcw on new connections (default=0 off)?"); SYSCTL_ADD_U16(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_pacing), OID_AUTO, "min_burst", CTLFLAG_RW, &rack_pacing_min_seg, 0, "What is the min burst size for pacing (0 disables)?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_pacing), OID_AUTO, "divisor", CTLFLAG_RW, &rack_default_pacing_divisor, 4, "What is the default divisor given to the rl code?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_pacing), OID_AUTO, "fillcw_max_mult", CTLFLAG_RW, &rack_bw_multipler, 2, "What is the multiplier of the current gp_est that fillcw can increase the b/w too?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_pacing), OID_AUTO, "max_pace_over", CTLFLAG_RW, &rack_max_per_above, 30, "What is the maximum allowable percentage that we can pace above (so 30 = 130% of our goal)"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_pacing), OID_AUTO, "allow1mss", CTLFLAG_RW, &rack_pace_one_seg, 0, "Do we allow low b/w pacing of 1MSS instead of two (1.2Meg and less)?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_pacing), OID_AUTO, "limit_wsrtt", CTLFLAG_RW, &rack_limit_time_with_srtt, 0, "Do we limit pacing time based on srtt"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_pacing), OID_AUTO, "init_win", CTLFLAG_RW, &rack_default_init_window, 0, "Do we have a rack initial window 0 = system default"); SYSCTL_ADD_U16(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_pacing), OID_AUTO, "gp_per_ss", CTLFLAG_RW, &rack_per_of_gp_ss, 250, "If non zero, what percentage of goodput to pace at in slow start"); SYSCTL_ADD_U16(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_pacing), OID_AUTO, "gp_per_ca", CTLFLAG_RW, &rack_per_of_gp_ca, 150, "If non zero, what percentage of goodput to pace at in congestion avoidance"); SYSCTL_ADD_U16(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_pacing), OID_AUTO, "gp_per_rec", CTLFLAG_RW, &rack_per_of_gp_rec, 200, "If non zero, what percentage of goodput to pace at in recovery"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_pacing), OID_AUTO, "pace_max_seg", CTLFLAG_RW, &rack_hptsi_segments, 40, "What size is the max for TSO segments in pacing and burst mitigation"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_pacing), OID_AUTO, "burst_reduces", CTLFLAG_RW, &rack_slot_reduction, 4, "When doing only burst mitigation what is the reduce divisor"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_sysctl_root), OID_AUTO, "use_pacing", CTLFLAG_RW, &rack_pace_every_seg, 0, "If set we use pacing, if clear we use only the original burst mitigation"); SYSCTL_ADD_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_pacing), OID_AUTO, "rate_cap", CTLFLAG_RW, &rack_bw_rate_cap, 0, "If set we apply this value to the absolute rate cap used by pacing"); SYSCTL_ADD_U8(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_sysctl_root), OID_AUTO, "req_measure_cnt", CTLFLAG_RW, &rack_req_measurements, 1, "If doing dynamic pacing, how many measurements must be in before we start pacing?"); /* Hardware pacing */ rack_hw_pacing = SYSCTL_ADD_NODE(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_sysctl_root), OID_AUTO, "hdwr_pacing", CTLFLAG_RW | CTLFLAG_MPSAFE, 0, "Pacing related Controls"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_hw_pacing), OID_AUTO, "rwnd_factor", CTLFLAG_RW, &rack_hw_rwnd_factor, 2, "How many times does snd_wnd need to be bigger than pace_max_seg so we will hold off and get more acks?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_hw_pacing), OID_AUTO, "precheck", CTLFLAG_RW, &rack_hw_check_queue, 0, "Do we always precheck the hdwr pacing queue to avoid ENOBUF's?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_hw_pacing), OID_AUTO, "pace_enobuf_mult", CTLFLAG_RW, &rack_enobuf_hw_boost_mult, 0, "By how many time_betweens should we boost the pacing time if we see a ENOBUFS?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_hw_pacing), OID_AUTO, "pace_enobuf_max", CTLFLAG_RW, &rack_enobuf_hw_max, 2, "What is the max boost the pacing time if we see a ENOBUFS?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_hw_pacing), OID_AUTO, "pace_enobuf_min", CTLFLAG_RW, &rack_enobuf_hw_min, 2, "What is the min boost the pacing time if we see a ENOBUFS?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_hw_pacing), OID_AUTO, "enable", CTLFLAG_RW, &rack_enable_hw_pacing, 0, "Should RACK attempt to use hw pacing?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_hw_pacing), OID_AUTO, "rate_cap", CTLFLAG_RW, &rack_hw_rate_caps, 0, "Does the highest hardware pacing rate cap the rate we will send at??"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_hw_pacing), OID_AUTO, "uncap_per", CTLFLAG_RW, &rack_hw_rate_cap_per, 0, "If you go over b/w by this amount you will be uncapped (0 = never)"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_hw_pacing), OID_AUTO, "rate_min", CTLFLAG_RW, &rack_hw_rate_min, 0, "Do we need a minimum estimate of this many bytes per second in order to engage hw pacing?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_hw_pacing), OID_AUTO, "rate_to_low", CTLFLAG_RW, &rack_hw_rate_to_low, 0, "If we fall below this rate, dis-engage hw pacing?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_hw_pacing), OID_AUTO, "up_only", CTLFLAG_RW, &rack_hw_up_only, 0, "Do we allow hw pacing to lower the rate selected?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_hw_pacing), OID_AUTO, "extra_mss_precise", CTLFLAG_RW, &rack_hw_pace_extra_slots, 0, "If the rates between software and hardware match precisely how many extra time_betweens do we get?"); rack_timely = SYSCTL_ADD_NODE(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_sysctl_root), OID_AUTO, "timely", CTLFLAG_RW | CTLFLAG_MPSAFE, 0, "Rack Timely RTT Controls"); /* Timely based GP dynmics */ SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timely), OID_AUTO, "upper", CTLFLAG_RW, &rack_gp_per_bw_mul_up, 2, "Rack timely upper range for equal b/w (in percentage)"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timely), OID_AUTO, "lower", CTLFLAG_RW, &rack_gp_per_bw_mul_down, 4, "Rack timely lower range for equal b/w (in percentage)"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timely), OID_AUTO, "rtt_max_mul", CTLFLAG_RW, &rack_gp_rtt_maxmul, 3, "Rack timely multiplier of lowest rtt for rtt_max"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timely), OID_AUTO, "rtt_min_div", CTLFLAG_RW, &rack_gp_rtt_mindiv, 4, "Rack timely divisor used for rtt + (rtt * mul/divisor) for check for lower rtt"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timely), OID_AUTO, "rtt_min_mul", CTLFLAG_RW, &rack_gp_rtt_minmul, 1, "Rack timely multiplier used for rtt + (rtt * mul/divisor) for check for lower rtt"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timely), OID_AUTO, "decrease", CTLFLAG_RW, &rack_gp_decrease_per, 80, "Rack timely Beta value 80 = .8 (scaled by 100)"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timely), OID_AUTO, "increase", CTLFLAG_RW, &rack_gp_increase_per, 2, "Rack timely increase perentage of our GP multiplication factor"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timely), OID_AUTO, "lowerbound", CTLFLAG_RW, &rack_per_lower_bound, 50, "Rack timely lowest percentage we allow GP multiplier to fall to"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timely), OID_AUTO, "p5_upper", CTLFLAG_RW, &rack_gain_p5_ub, 250, "Profile 5 upper bound to timely gain"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timely), OID_AUTO, "upperboundss", CTLFLAG_RW, &rack_per_upper_bound_ss, 0, "Rack timely highest percentage we allow GP multiplier in SS to raise to (0 is no upperbound)"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timely), OID_AUTO, "upperboundca", CTLFLAG_RW, &rack_per_upper_bound_ca, 0, "Rack timely highest percentage we allow GP multiplier to CA raise to (0 is no upperbound)"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timely), OID_AUTO, "dynamicgp", CTLFLAG_RW, &rack_do_dyn_mul, 0, "Rack timely do we enable dynmaic timely goodput by default"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timely), OID_AUTO, "no_rec_red", CTLFLAG_RW, &rack_gp_no_rec_chg, 1, "Rack timely do we prohibit the recovery multiplier from being lowered"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timely), OID_AUTO, "red_clear_cnt", CTLFLAG_RW, &rack_timely_dec_clear, 6, "Rack timely what threshold do we count to before another boost during b/w decent"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timely), OID_AUTO, "max_push_rise", CTLFLAG_RW, &rack_timely_max_push_rise, 3, "Rack timely how many times do we push up with b/w increase"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timely), OID_AUTO, "max_push_drop", CTLFLAG_RW, &rack_timely_max_push_drop, 3, "Rack timely how many times do we push back on b/w decent"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timely), OID_AUTO, "min_segs", CTLFLAG_RW, &rack_timely_min_segs, 4, "Rack timely when setting the cwnd what is the min num segments"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timely), OID_AUTO, "noback_max", CTLFLAG_RW, &rack_use_max_for_nobackoff, 0, "Rack timely when deciding if to backoff on a loss, do we use under max rtt else min"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timely), OID_AUTO, "interim_timely_only", CTLFLAG_RW, &rack_timely_int_timely_only, 0, "Rack timely when doing interim timely's do we only do timely (no b/w consideration)"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timely), OID_AUTO, "nonstop", CTLFLAG_RW, &rack_timely_no_stopping, 0, "Rack timely don't stop increase"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timely), OID_AUTO, "dec_raise_thresh", CTLFLAG_RW, &rack_down_raise_thresh, 100, "If the CA or SS is below this threshold raise on the first 3 b/w lowers (0=always)"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timely), OID_AUTO, "bottom_drag_segs", CTLFLAG_RW, &rack_req_segs, 1, "Bottom dragging if not these many segments outstanding and room"); /* TLP and Rack related parameters */ rack_tlp = SYSCTL_ADD_NODE(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_sysctl_root), OID_AUTO, "tlp", CTLFLAG_RW | CTLFLAG_MPSAFE, 0, "TLP and Rack related Controls"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_tlp), OID_AUTO, "use_rrr", CTLFLAG_RW, &use_rack_rr, 1, "Do we use Rack Rapid Recovery"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_tlp), OID_AUTO, "post_rec_labc", CTLFLAG_RW, &rack_max_abc_post_recovery, 2, "Since we do early recovery, do we override the l_abc to a value, if so what?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_tlp), OID_AUTO, "nonrxt_use_cr", CTLFLAG_RW, &rack_non_rxt_use_cr, 0, "Do we use ss/ca rate if in recovery we are transmitting a new data chunk"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_tlp), OID_AUTO, "tlpmethod", CTLFLAG_RW, &rack_tlp_threshold_use, TLP_USE_TWO_ONE, "What method do we do for TLP time calc 0=no-de-ack-comp, 1=ID, 2=2.1, 3=2.2"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_tlp), OID_AUTO, "limit", CTLFLAG_RW, &rack_tlp_limit, 2, "How many TLP's can be sent without sending new data"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_tlp), OID_AUTO, "use_greater", CTLFLAG_RW, &rack_tlp_use_greater, 1, "Should we use the rack_rtt time if its greater than srtt"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_tlp), OID_AUTO, "tlpminto", CTLFLAG_RW, &rack_tlp_min, 10000, "TLP minimum timeout per the specification (in microseconds)"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_tlp), OID_AUTO, "send_oldest", CTLFLAG_RW, &rack_always_send_oldest, 0, "Should we always send the oldest TLP and RACK-TLP"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_tlp), OID_AUTO, "rack_tlimit", CTLFLAG_RW, &rack_limited_retran, 0, "How many times can a rack timeout drive out sends"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_tlp), OID_AUTO, "tlp_cwnd_flag", CTLFLAG_RW, &rack_lower_cwnd_at_tlp, 0, "When a TLP completes a retran should we enter recovery"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_tlp), OID_AUTO, "reorder_thresh", CTLFLAG_RW, &rack_reorder_thresh, 2, "What factor for rack will be added when seeing reordering (shift right)"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_tlp), OID_AUTO, "rtt_tlp_thresh", CTLFLAG_RW, &rack_tlp_thresh, 1, "What divisor for TLP rtt/retran will be added (1=rtt, 2=1/2 rtt etc)"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_tlp), OID_AUTO, "reorder_fade", CTLFLAG_RW, &rack_reorder_fade, 60000000, "Does reorder detection fade, if so how many microseconds (0 means never)"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_tlp), OID_AUTO, "pktdelay", CTLFLAG_RW, &rack_pkt_delay, 1000, "Extra RACK time (in microseconds) besides reordering thresh"); /* Timer related controls */ rack_timers = SYSCTL_ADD_NODE(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_sysctl_root), OID_AUTO, "timers", CTLFLAG_RW | CTLFLAG_MPSAFE, 0, "Timer related controls"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timers), OID_AUTO, "persmin", CTLFLAG_RW, &rack_persist_min, 250000, "What is the minimum time in microseconds between persists"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timers), OID_AUTO, "persmax", CTLFLAG_RW, &rack_persist_max, 2000000, "What is the largest delay in microseconds between persists"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timers), OID_AUTO, "delayed_ack", CTLFLAG_RW, &rack_delayed_ack_time, 40000, "Delayed ack time (40ms in microseconds)"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timers), OID_AUTO, "minrto", CTLFLAG_RW, &rack_rto_min, 30000, "Minimum RTO in microseconds -- set with caution below 1000 due to TLP"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timers), OID_AUTO, "maxrto", CTLFLAG_RW, &rack_rto_max, 4000000, "Maximum RTO in microseconds -- should be at least as large as min_rto"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_timers), OID_AUTO, "minto", CTLFLAG_RW, &rack_min_to, 1000, "Minimum rack timeout in microseconds"); /* Measure controls */ rack_measure = SYSCTL_ADD_NODE(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_sysctl_root), OID_AUTO, "measure", CTLFLAG_RW | CTLFLAG_MPSAFE, 0, "Measure related controls"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_measure), OID_AUTO, "wma_divisor", CTLFLAG_RW, &rack_wma_divisor, 8, "When doing b/w calculation what is the divisor for the WMA"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_measure), OID_AUTO, "end_cwnd", CTLFLAG_RW, &rack_cwnd_block_ends_measure, 0, "Does a cwnd just-return end the measurement window (app limited)"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_measure), OID_AUTO, "end_rwnd", CTLFLAG_RW, &rack_rwnd_block_ends_measure, 0, "Does an rwnd just-return end the measurement window (app limited -- not persists)"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_measure), OID_AUTO, "min_target", CTLFLAG_RW, &rack_def_data_window, 20, "What is the minimum target window (in mss) for a GP measurements"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_measure), OID_AUTO, "goal_bdp", CTLFLAG_RW, &rack_goal_bdp, 2, "What is the goal BDP to measure"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_measure), OID_AUTO, "min_srtts", CTLFLAG_RW, &rack_min_srtts, 1, "What is the goal BDP to measure"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_measure), OID_AUTO, "min_measure_tim", CTLFLAG_RW, &rack_min_measure_usec, 0, "What is the Minimum time time for a measurement if 0, this is off"); /* Features */ rack_features = SYSCTL_ADD_NODE(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_sysctl_root), OID_AUTO, "features", CTLFLAG_RW | CTLFLAG_MPSAFE, 0, "Feature controls"); SYSCTL_ADD_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_features), OID_AUTO, "rxt_clamp_thresh", CTLFLAG_RW, &rack_rxt_clamp_thresh, 0, "Bit encoded clamping setup bits CCCC CCCCC UUUU UULF PPPP PPPP PPPP PPPP"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_features), OID_AUTO, "hybrid_set_maxseg", CTLFLAG_RW, &rack_hybrid_allow_set_maxseg, 0, "Should hybrid pacing allow the setmss command"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_features), OID_AUTO, "cmpack", CTLFLAG_RW, &rack_use_cmp_acks, 1, "Should RACK have LRO send compressed acks"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_features), OID_AUTO, "fsb", CTLFLAG_RW, &rack_use_fsb, 1, "Should RACK use the fast send block?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_features), OID_AUTO, "rfo", CTLFLAG_RW, &rack_use_rfo, 1, "Should RACK use rack_fast_output()?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_features), OID_AUTO, "rsmrfo", CTLFLAG_RW, &rack_use_rsm_rfo, 1, "Should RACK use rack_fast_rsm_output()?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_features), OID_AUTO, "non_paced_lro_queue", CTLFLAG_RW, &rack_enable_mqueue_for_nonpaced, 0, "Should RACK use mbuf queuing for non-paced connections"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_features), OID_AUTO, "hystartplusplus", CTLFLAG_RW, &rack_do_hystart, 0, "Should RACK enable HyStart++ on connections?"); /* Misc rack controls */ rack_misc = SYSCTL_ADD_NODE(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_sysctl_root), OID_AUTO, "misc", CTLFLAG_RW | CTLFLAG_MPSAFE, 0, "Misc related controls"); #ifdef TCP_ACCOUNTING SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "tcp_acct", CTLFLAG_RW, &rack_tcp_accounting, 0, "Should we turn on TCP accounting for all rack sessions?"); #endif SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "dnd", CTLFLAG_RW, &rack_dnd_default, 0, "Do not disturb default for rack_rrr = 3"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "sad_seg_per", CTLFLAG_RW, &sad_seg_size_per, 800, "Percentage of segment size needed in a sack 800 = 80.0?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "rxt_controls", CTLFLAG_RW, &rack_rxt_controls, 0, "Retransmit sending size controls (valid values 0, 1, 2 default=1)?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "rack_hibeta", CTLFLAG_RW, &rack_hibeta_setting, 0, "Do we ue a high beta (80 instead of 50)?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "apply_rtt_with_low_conf", CTLFLAG_RW, &rack_apply_rtt_with_reduced_conf, 0, "When a persist or keep-alive probe is not answered do we calculate rtt on subsequent answers?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "rack_dsack_ctl", CTLFLAG_RW, &rack_dsack_std_based, 3, "How do we process dsack with respect to rack timers, bit field, 3 is standards based?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "prr_addback_max", CTLFLAG_RW, &rack_prr_addbackmax, 2, "What is the maximum number of MSS we allow to be added back if prr can't send all its data?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "stats_gets_ms", CTLFLAG_RW, &rack_stats_gets_ms_rtt, 1, "What do we feed the stats framework (1 = ms_rtt, 0 = us_rtt, 2 = ms_rtt from hdwr, > 2 usec rtt from hdwr)?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "clientlowbuf", CTLFLAG_RW, &rack_client_low_buf, 0, "Client low buffer level (below this we are more aggressive in DGP exiting recovery (0 = off)?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "defprofile", CTLFLAG_RW, &rack_def_profile, 0, "Should RACK use a default profile (0=no, num == profile num)?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "shared_cwnd", CTLFLAG_RW, &rack_enable_shared_cwnd, 1, "Should RACK try to use the shared cwnd on connections where allowed"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "limits_on_scwnd", CTLFLAG_RW, &rack_limits_scwnd, 1, "Should RACK place low end time limits on the shared cwnd feature"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "no_prr", CTLFLAG_RW, &rack_disable_prr, 0, "Should RACK not use prr and only pace (must have pacing on)"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "bb_verbose", CTLFLAG_RW, &rack_verbose_logging, 0, "Should RACK black box logging be verbose"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "data_after_close", CTLFLAG_RW, &rack_ignore_data_after_close, 1, "Do we hold off sending a RST until all pending data is ack'd"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "no_sack_needed", CTLFLAG_RW, &rack_sack_not_required, 1, "Do we allow rack to run on connections not supporting SACK"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "prr_sendalot", CTLFLAG_RW, &rack_send_a_lot_in_prr, 1, "Send a lot in prr"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "autoscale", CTLFLAG_RW, &rack_autosndbuf_inc, 20, "What percentage should rack scale up its snd buffer by?"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "rnds_for_rxt_clamp", CTLFLAG_RW, &rack_rxt_min_rnds, 10, "Number of rounds needed between RTT clamps due to high loss rates"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "rnds_for_unclamp", CTLFLAG_RW, &rack_unclamp_round_thresh, 100, "Number of rounds needed with no loss to unclamp"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "rxt_threshs_for_unclamp", CTLFLAG_RW, &rack_unclamp_rxt_thresh, 5, "Percentage of retransmits we need to be under to unclamp (5 = .5 percent)\n"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "clamp_ss_upper", CTLFLAG_RW, &rack_clamp_ss_upper, 110, "Clamp percentage ceiling in SS?"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "clamp_ca_upper", CTLFLAG_RW, &rack_clamp_ca_upper, 110, "Clamp percentage ceiling in CA?"); /* Sack Attacker detection stuff */ SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_attack), OID_AUTO, "merge_out", CTLFLAG_RW, &rack_merge_out_sacks_on_attack, 0, "Do we merge the sendmap when we decide we are being attacked?"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_attack), OID_AUTO, "detect_highsackratio", CTLFLAG_RW, &rack_highest_sack_thresh_seen, 0, "Highest sack to ack ratio seen"); SYSCTL_ADD_U32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_attack), OID_AUTO, "detect_highmoveratio", CTLFLAG_RW, &rack_highest_move_thresh_seen, 0, "Highest move to non-move ratio seen"); rack_ack_total = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_attack), OID_AUTO, "acktotal", CTLFLAG_RD, &rack_ack_total, "Total number of Ack's"); rack_express_sack = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_attack), OID_AUTO, "exp_sacktotal", CTLFLAG_RD, &rack_express_sack, "Total expresss number of Sack's"); rack_sack_total = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_attack), OID_AUTO, "sacktotal", CTLFLAG_RD, &rack_sack_total, "Total number of SACKs"); rack_move_none = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_attack), OID_AUTO, "move_none", CTLFLAG_RD, &rack_move_none, "Total number of SACK index reuse of positions under threshold"); rack_move_some = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_attack), OID_AUTO, "move_some", CTLFLAG_RD, &rack_move_some, "Total number of SACK index reuse of positions over threshold"); rack_sack_attacks_detected = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_attack), OID_AUTO, "attacks", CTLFLAG_RD, &rack_sack_attacks_detected, "Total number of SACK attackers that had sack disabled"); rack_sack_attacks_reversed = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_attack), OID_AUTO, "reversed", CTLFLAG_RD, &rack_sack_attacks_reversed, "Total number of SACK attackers that were later determined false positive"); rack_sack_attacks_suspect = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_attack), OID_AUTO, "suspect", CTLFLAG_RD, &rack_sack_attacks_suspect, "Total number of SACKs that triggered early detection"); rack_sack_used_next_merge = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_attack), OID_AUTO, "nextmerge", CTLFLAG_RD, &rack_sack_used_next_merge, "Total number of times we used the next merge"); rack_sack_used_prev_merge = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_attack), OID_AUTO, "prevmerge", CTLFLAG_RD, &rack_sack_used_prev_merge, "Total number of times we used the prev merge"); /* Counters */ rack_total_bytes = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "totalbytes", CTLFLAG_RD, &rack_total_bytes, "Total number of bytes sent"); rack_fto_send = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "fto_send", CTLFLAG_RD, &rack_fto_send, "Total number of rack_fast_output sends"); rack_fto_rsm_send = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "fto_rsm_send", CTLFLAG_RD, &rack_fto_rsm_send, "Total number of rack_fast_rsm_output sends"); rack_nfto_resend = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "nfto_resend", CTLFLAG_RD, &rack_nfto_resend, "Total number of rack_output retransmissions"); rack_non_fto_send = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "nfto_send", CTLFLAG_RD, &rack_non_fto_send, "Total number of rack_output first sends"); rack_extended_rfo = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "rfo_extended", CTLFLAG_RD, &rack_extended_rfo, "Total number of times we extended rfo"); rack_hw_pace_init_fail = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "hwpace_init_fail", CTLFLAG_RD, &rack_hw_pace_init_fail, "Total number of times we failed to initialize hw pacing"); rack_hw_pace_lost = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "hwpace_lost", CTLFLAG_RD, &rack_hw_pace_lost, "Total number of times we failed to initialize hw pacing"); rack_tlp_tot = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "tlp_to_total", CTLFLAG_RD, &rack_tlp_tot, "Total number of tail loss probe expirations"); rack_tlp_newdata = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "tlp_new", CTLFLAG_RD, &rack_tlp_newdata, "Total number of tail loss probe sending new data"); rack_tlp_retran = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "tlp_retran", CTLFLAG_RD, &rack_tlp_retran, "Total number of tail loss probe sending retransmitted data"); rack_tlp_retran_bytes = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "tlp_retran_bytes", CTLFLAG_RD, &rack_tlp_retran_bytes, "Total bytes of tail loss probe sending retransmitted data"); rack_to_tot = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "rack_to_tot", CTLFLAG_RD, &rack_to_tot, "Total number of times the rack to expired"); rack_saw_enobuf = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "saw_enobufs", CTLFLAG_RD, &rack_saw_enobuf, "Total number of times a sends returned enobuf for non-hdwr paced connections"); rack_saw_enobuf_hw = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "saw_enobufs_hw", CTLFLAG_RD, &rack_saw_enobuf_hw, "Total number of times a send returned enobuf for hdwr paced connections"); rack_saw_enetunreach = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "saw_enetunreach", CTLFLAG_RD, &rack_saw_enetunreach, "Total number of times a send received a enetunreachable"); rack_hot_alloc = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "alloc_hot", CTLFLAG_RD, &rack_hot_alloc, "Total allocations from the top of our list"); rack_to_alloc = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "allocs", CTLFLAG_RD, &rack_to_alloc, "Total allocations of tracking structures"); rack_to_alloc_hard = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "allochard", CTLFLAG_RD, &rack_to_alloc_hard, "Total allocations done with sleeping the hard way"); rack_to_alloc_emerg = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "allocemerg", CTLFLAG_RD, &rack_to_alloc_emerg, "Total allocations done from emergency cache"); rack_to_alloc_limited = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "alloc_limited", CTLFLAG_RD, &rack_to_alloc_limited, "Total allocations dropped due to limit"); rack_alloc_limited_conns = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "alloc_limited_conns", CTLFLAG_RD, &rack_alloc_limited_conns, "Connections with allocations dropped due to limit"); rack_split_limited = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "split_limited", CTLFLAG_RD, &rack_split_limited, "Split allocations dropped due to limit"); rack_rxt_clamps_cwnd = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "rxt_clamps_cwnd", CTLFLAG_RD, &rack_rxt_clamps_cwnd, "Number of times that excessive rxt clamped the cwnd down"); rack_rxt_clamps_cwnd_uniq = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "rxt_clamps_cwnd_uniq", CTLFLAG_RD, &rack_rxt_clamps_cwnd_uniq, "Number of connections that have had excessive rxt clamped the cwnd down"); rack_persists_sends = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "persist_sends", CTLFLAG_RD, &rack_persists_sends, "Number of times we sent a persist probe"); rack_persists_acks = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "persist_acks", CTLFLAG_RD, &rack_persists_acks, "Number of times a persist probe was acked"); rack_persists_loss = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "persist_loss", CTLFLAG_RD, &rack_persists_loss, "Number of times we detected a lost persist probe (no ack)"); rack_persists_lost_ends = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "persist_loss_ends", CTLFLAG_RD, &rack_persists_lost_ends, "Number of lost persist probe (no ack) that the run ended with a PERSIST abort"); #ifdef INVARIANTS rack_adjust_map_bw = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "map_adjust_req", CTLFLAG_RD, &rack_adjust_map_bw, "Number of times we hit the case where the sb went up and down on a sendmap entry"); #endif rack_multi_single_eq = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "cmp_ack_equiv", CTLFLAG_RD, &rack_multi_single_eq, "Number of compressed acks total represented"); rack_proc_non_comp_ack = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "cmp_ack_not", CTLFLAG_RD, &rack_proc_non_comp_ack, "Number of non compresseds acks that we processed"); rack_sack_proc_all = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "sack_long", CTLFLAG_RD, &rack_sack_proc_all, "Total times we had to walk whole list for sack processing"); rack_sack_proc_restart = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "sack_restart", CTLFLAG_RD, &rack_sack_proc_restart, "Total times we had to walk whole list due to a restart"); rack_sack_proc_short = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "sack_short", CTLFLAG_RD, &rack_sack_proc_short, "Total times we took shortcut for sack processing"); rack_sack_skipped_acked = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_attack), OID_AUTO, "skipacked", CTLFLAG_RD, &rack_sack_skipped_acked, "Total number of times we skipped previously sacked"); rack_sack_splits = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_attack), OID_AUTO, "ofsplit", CTLFLAG_RD, &rack_sack_splits, "Total number of times we did the old fashion tree split"); rack_input_idle_reduces = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "idle_reduce_oninput", CTLFLAG_RD, &rack_input_idle_reduces, "Total number of idle reductions on input"); rack_collapsed_win_seen = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "collapsed_win_seen", CTLFLAG_RD, &rack_collapsed_win_seen, "Total number of collapsed window events seen (where our window shrinks)"); rack_collapsed_win = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "collapsed_win", CTLFLAG_RD, &rack_collapsed_win, "Total number of collapsed window events where we mark packets"); rack_collapsed_win_rxt = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "collapsed_win_rxt", CTLFLAG_RD, &rack_collapsed_win_rxt, "Total number of packets that were retransmitted"); rack_collapsed_win_rxt_bytes = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "collapsed_win_bytes", CTLFLAG_RD, &rack_collapsed_win_rxt_bytes, "Total number of bytes that were retransmitted"); rack_try_scwnd = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), OID_AUTO, "tried_scwnd", CTLFLAG_RD, &rack_try_scwnd, "Total number of scwnd attempts"); COUNTER_ARRAY_ALLOC(rack_out_size, TCP_MSS_ACCT_SIZE, M_WAITOK); SYSCTL_ADD_COUNTER_U64_ARRAY(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_sysctl_root), OID_AUTO, "outsize", CTLFLAG_RD, rack_out_size, TCP_MSS_ACCT_SIZE, "MSS send sizes"); COUNTER_ARRAY_ALLOC(rack_opts_arry, RACK_OPTS_SIZE, M_WAITOK); SYSCTL_ADD_COUNTER_U64_ARRAY(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_sysctl_root), OID_AUTO, "opts", CTLFLAG_RD, rack_opts_arry, RACK_OPTS_SIZE, "RACK Option Stats"); SYSCTL_ADD_PROC(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_sysctl_root), OID_AUTO, "clear", CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_MPSAFE, &rack_clear_counter, 0, sysctl_rack_clear, "IU", "Clear counters"); } static uint32_t rc_init_window(struct tcp_rack *rack) { uint32_t win; if (rack->rc_init_win == 0) { /* * Nothing set by the user, use the system stack * default. */ return (tcp_compute_initwnd(tcp_maxseg(rack->rc_tp))); } win = ctf_fixed_maxseg(rack->rc_tp) * rack->rc_init_win; return (win); } static uint64_t rack_get_fixed_pacing_bw(struct tcp_rack *rack) { if (IN_FASTRECOVERY(rack->rc_tp->t_flags)) return (rack->r_ctl.rc_fixed_pacing_rate_rec); else if (rack->r_ctl.cwnd_to_use < rack->rc_tp->snd_ssthresh) return (rack->r_ctl.rc_fixed_pacing_rate_ss); else return (rack->r_ctl.rc_fixed_pacing_rate_ca); } static void rack_log_hybrid_bw(struct tcp_rack *rack, uint32_t seq, uint64_t cbw, uint64_t tim, uint64_t data, uint8_t mod, uint16_t aux, struct tcp_sendfile_track *cur, int line) { #ifdef TCP_REQUEST_TRK int do_log = 0; /* * The rate cap one is noisy and only should come out when normal BB logging * is enabled, the other logs (not RATE_CAP and NOT CAP_CALC) only come out * once per chunk and make up the BBpoint that can be turned on by the client. */ if ((mod == HYBRID_LOG_RATE_CAP) || (mod == HYBRID_LOG_CAP_CALC)) { /* * The very noisy two need to only come out when * we have verbose logging on. */ if (rack_verbose_logging != 0) do_log = tcp_bblogging_on(rack->rc_tp); else do_log = 0; } else if (mod != HYBRID_LOG_BW_MEASURE) { /* * All other less noisy logs here except the measure which * also needs to come out on the point and the log. */ do_log = tcp_bblogging_on(rack->rc_tp); } else { do_log = tcp_bblogging_point_on(rack->rc_tp, TCP_BBPOINT_REQ_LEVEL_LOGGING); } if (do_log) { union tcp_log_stackspecific log; struct timeval tv; uint64_t lt_bw; /* Convert our ms to a microsecond */ memset(&log, 0, sizeof(log)); log.u_bbr.cwnd_gain = line; log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.rttProp = tim; log.u_bbr.bw_inuse = cbw; log.u_bbr.delRate = rack_get_gp_est(rack); lt_bw = rack_get_lt_bw(rack); log.u_bbr.flex1 = seq; log.u_bbr.pacing_gain = aux; /* lt_bw = < flex3 | flex2 > */ log.u_bbr.flex2 = (uint32_t)(lt_bw & 0x00000000ffffffff); log.u_bbr.flex3 = (uint32_t)((lt_bw >> 32) & 0x00000000ffffffff); /* Record the last obtained us rtt in inflight */ if (cur == NULL) { /* Make sure we are looking at the right log if an overide comes in */ cur = rack->r_ctl.rc_last_sft; } if (rack->r_ctl.rack_rs.rs_flags != RACK_RTT_EMPTY) log.u_bbr.inflight = rack->r_ctl.rack_rs.rs_us_rtt; else { /* Use the last known rtt i.e. the rack-rtt */ log.u_bbr.inflight = rack->rc_rack_rtt; } if (cur != NULL) { uint64_t off; log.u_bbr.cur_del_rate = cur->deadline; if ((mod == HYBRID_LOG_RATE_CAP) || (mod == HYBRID_LOG_CAP_CALC)) { /* start = < lost | pkt_epoch > */ log.u_bbr.pkt_epoch = (uint32_t)(cur->start & 0x00000000ffffffff); log.u_bbr.lost = (uint32_t)((cur->start >> 32) & 0x00000000ffffffff); log.u_bbr.flex6 = cur->start_seq; log.u_bbr.pkts_out = cur->end_seq; } else { /* start = < lost | pkt_epoch > */ log.u_bbr.pkt_epoch = (uint32_t)(cur->start & 0x00000000ffffffff); log.u_bbr.lost = (uint32_t)((cur->start >> 32) & 0x00000000ffffffff); /* end = < pkts_out | flex6 > */ log.u_bbr.flex6 = (uint32_t)(cur->end & 0x00000000ffffffff); log.u_bbr.pkts_out = (uint32_t)((cur->end >> 32) & 0x00000000ffffffff); } /* first_send = */ log.u_bbr.epoch = (uint32_t)(cur->first_send & 0x00000000ffffffff); log.u_bbr.lt_epoch = (uint32_t)((cur->first_send >> 32) & 0x00000000ffffffff); /* localtime = */ log.u_bbr.applimited = (uint32_t)(cur->localtime & 0x00000000ffffffff); log.u_bbr.delivered = (uint32_t)((cur->localtime >> 32) & 0x00000000ffffffff); #ifdef TCP_REQUEST_TRK off = (uint64_t)(cur) - (uint64_t)(&rack->rc_tp->t_tcpreq_info[0]); log.u_bbr.bbr_substate = (uint8_t)(off / sizeof(struct tcp_sendfile_track)); #endif log.u_bbr.flex4 = (uint32_t)(rack->rc_tp->t_sndbytes - cur->sent_at_fs); log.u_bbr.flex5 = (uint32_t)(rack->rc_tp->t_snd_rxt_bytes - cur->rxt_at_fs); log.u_bbr.flex7 = (uint16_t)cur->hybrid_flags; } else { log.u_bbr.flex7 = 0xffff; log.u_bbr.cur_del_rate = 0xffffffffffffffff; } /* * Compose bbr_state to be a bit wise 0000ADHF * where A is the always_pace flag * where D is the dgp_on flag * where H is the hybrid_mode on flag * where F is the use_fixed_rate flag. */ log.u_bbr.bbr_state = rack->rc_always_pace; log.u_bbr.bbr_state <<= 1; log.u_bbr.bbr_state |= rack->dgp_on; log.u_bbr.bbr_state <<= 1; log.u_bbr.bbr_state |= rack->rc_hybrid_mode; log.u_bbr.bbr_state <<= 1; log.u_bbr.bbr_state |= rack->use_fixed_rate; log.u_bbr.flex8 = mod; tcp_log_event(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, TCP_HYBRID_PACING_LOG, 0, 0, &log, false, NULL, __func__, __LINE__, &tv); } #endif } #ifdef TCP_REQUEST_TRK static void rack_log_hybrid_sends(struct tcp_rack *rack, struct tcp_sendfile_track *cur, int line) { if (tcp_bblogging_point_on(rack->rc_tp, TCP_BBPOINT_REQ_LEVEL_LOGGING)) { union tcp_log_stackspecific log; struct timeval tv; uint64_t off; /* Convert our ms to a microsecond */ memset(&log, 0, sizeof(log)); log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.cur_del_rate = rack->rc_tp->t_sndbytes; log.u_bbr.delRate = cur->sent_at_fs; log.u_bbr.rttProp = rack->rc_tp->t_snd_rxt_bytes; log.u_bbr.bw_inuse = cur->rxt_at_fs; log.u_bbr.cwnd_gain = line; off = (uint64_t)(cur) - (uint64_t)(&rack->rc_tp->t_tcpreq_info[0]); log.u_bbr.bbr_substate = (uint8_t)(off / sizeof(struct tcp_sendfile_track)); /* start = < flex1 | flex2 > */ log.u_bbr.flex2 = (uint32_t)(cur->start & 0x00000000ffffffff); log.u_bbr.flex1 = (uint32_t)((cur->start >> 32) & 0x00000000ffffffff); /* end = < flex3 | flex4 > */ log.u_bbr.flex4 = (uint32_t)(cur->end & 0x00000000ffffffff); log.u_bbr.flex3 = (uint32_t)((cur->end >> 32) & 0x00000000ffffffff); /* localtime = */ log.u_bbr.applimited = (uint32_t)(cur->localtime & 0x00000000ffffffff); log.u_bbr.delivered = (uint32_t)((cur->localtime >> 32) & 0x00000000ffffffff); /* client timestamp = */ log.u_bbr.epoch = (uint32_t)(cur->timestamp & 0x00000000ffffffff); log.u_bbr.lt_epoch = (uint32_t)((cur->timestamp >> 32) & 0x00000000ffffffff); /* now set all the flags in */ log.u_bbr.pkts_out = cur->hybrid_flags; log.u_bbr.flex6 = cur->flags; /* * Last send time = note we do not distinguish cases * where a false retransmit occurred so first_send <-> lastsend may * include longer time then it actually took if we have a false rxt. */ log.u_bbr.pkt_epoch = (uint32_t)(rack->r_ctl.last_tmit_time_acked & 0x00000000ffffffff); log.u_bbr.flex5 = (uint32_t)((rack->r_ctl.last_tmit_time_acked >> 32) & 0x00000000ffffffff); log.u_bbr.flex8 = HYBRID_LOG_SENT_LOST; tcp_log_event(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, TCP_HYBRID_PACING_LOG, 0, 0, &log, false, NULL, __func__, __LINE__, &tv); } } #endif static inline uint64_t rack_compensate_for_linerate(struct tcp_rack *rack, uint64_t bw) { uint64_t ret_bw, ether; uint64_t u_segsiz; ether = rack->rc_tp->t_maxseg + sizeof(struct tcphdr); if (rack->r_is_v6){ #ifdef INET6 ether += sizeof(struct ip6_hdr); #endif ether += 14; /* eheader size 6+6+2 */ } else { #ifdef INET ether += sizeof(struct ip); #endif ether += 14; /* eheader size 6+6+2 */ } u_segsiz = (uint64_t)min(ctf_fixed_maxseg(rack->rc_tp), rack->r_ctl.rc_pace_min_segs); ret_bw = bw; ret_bw *= ether; ret_bw /= u_segsiz; return (ret_bw); } static void rack_rate_cap_bw(struct tcp_rack *rack, uint64_t *bw, int *capped) { #ifdef TCP_REQUEST_TRK struct timeval tv; uint64_t timenow, timeleft, lenleft, lengone, calcbw; #endif if (rack->r_ctl.bw_rate_cap == 0) return; #ifdef TCP_REQUEST_TRK if (rack->rc_catch_up && rack->rc_hybrid_mode && (rack->r_ctl.rc_last_sft != NULL)) { /* * We have a dynamic cap. The original target * is in bw_rate_cap, but we need to look at * how long it is until we hit the deadline. */ struct tcp_sendfile_track *ent; ent = rack->r_ctl.rc_last_sft; microuptime(&tv); timenow = tcp_tv_to_lusectick(&tv); if (timenow >= ent->deadline) { /* No time left we do DGP only */ rack_log_hybrid_bw(rack, rack->rc_tp->snd_max, 0, 0, 0, HYBRID_LOG_OUTOFTIME, 0, ent, __LINE__); rack->r_ctl.bw_rate_cap = 0; return; } /* We have the time */ timeleft = rack->r_ctl.rc_last_sft->deadline - timenow; if (timeleft < HPTS_MSEC_IN_SEC) { /* If there is less than a ms left just use DGPs rate */ rack_log_hybrid_bw(rack, rack->rc_tp->snd_max, 0, timeleft, 0, HYBRID_LOG_OUTOFTIME, 0, ent, __LINE__); rack->r_ctl.bw_rate_cap = 0; return; } /* * Now lets find the amount of data left to send. * * Now ideally we want to use the end_seq to figure out how much more * but it might not be possible (only if we have the TRACK_FG_COMP on the entry.. */ if (ent->flags & TCP_TRK_TRACK_FLG_COMP) { if (SEQ_GT(ent->end_seq, rack->rc_tp->snd_una)) lenleft = ent->end_seq - rack->rc_tp->snd_una; else { /* TSNH, we should catch it at the send */ rack_log_hybrid_bw(rack, rack->rc_tp->snd_max, 0, timeleft, 0, HYBRID_LOG_CAPERROR, 0, ent, __LINE__); rack->r_ctl.bw_rate_cap = 0; return; } } else { /* * The hard way, figure out how much is gone and then * take that away from the total the client asked for * (thats off by tls overhead if this is tls). */ if (SEQ_GT(rack->rc_tp->snd_una, ent->start_seq)) lengone = rack->rc_tp->snd_una - ent->start_seq; else lengone = 0; if (lengone < (ent->end - ent->start)) lenleft = (ent->end - ent->start) - lengone; else { /* TSNH, we should catch it at the send */ rack_log_hybrid_bw(rack, rack->rc_tp->snd_max, 0, timeleft, lengone, HYBRID_LOG_CAPERROR, 0, ent, __LINE__); rack->r_ctl.bw_rate_cap = 0; return; } } if (lenleft == 0) { /* We have it all sent */ rack_log_hybrid_bw(rack, rack->rc_tp->snd_max, 0, timeleft, lenleft, HYBRID_LOG_ALLSENT, 0, ent, __LINE__); if (rack->r_ctl.bw_rate_cap) goto normal_ratecap; else return; } calcbw = lenleft * HPTS_USEC_IN_SEC; calcbw /= timeleft; /* Now we must compensate for IP/TCP overhead */ calcbw = rack_compensate_for_linerate(rack, calcbw); /* Update the bit rate cap */ rack->r_ctl.bw_rate_cap = calcbw; if ((rack->r_ctl.rc_last_sft->hybrid_flags & TCP_HYBRID_PACING_S_MSS) && (rack_hybrid_allow_set_maxseg == 1) && ((rack->r_ctl.rc_last_sft->hybrid_flags & TCP_HYBRID_PACING_SETMSS) == 0)) { /* Lets set in a smaller mss possibly here to match our rate-cap */ uint32_t orig_max; orig_max = rack->r_ctl.rc_pace_max_segs; rack->r_ctl.rc_last_sft->hybrid_flags |= TCP_HYBRID_PACING_SETMSS; rack->r_ctl.rc_pace_max_segs = rack_get_pacing_len(rack, calcbw, ctf_fixed_maxseg(rack->rc_tp)); rack_log_type_pacing_sizes(rack->rc_tp, rack, rack->r_ctl.client_suggested_maxseg, orig_max, __LINE__, 5); } rack_log_hybrid_bw(rack, rack->rc_tp->snd_max, calcbw, timeleft, lenleft, HYBRID_LOG_CAP_CALC, 0, ent, __LINE__); if ((calcbw > 0) && (*bw > calcbw)) { rack_log_hybrid_bw(rack, rack->rc_tp->snd_max, *bw, ent->deadline, lenleft, HYBRID_LOG_RATE_CAP, 0, ent, __LINE__); *capped = 1; *bw = calcbw; } return; } normal_ratecap: #endif if ((rack->r_ctl.bw_rate_cap > 0) && (*bw > rack->r_ctl.bw_rate_cap)) { #ifdef TCP_REQUEST_TRK if (rack->rc_hybrid_mode && rack->rc_catch_up && (rack->r_ctl.rc_last_sft->hybrid_flags & TCP_HYBRID_PACING_S_MSS) && (rack_hybrid_allow_set_maxseg == 1) && ((rack->r_ctl.rc_last_sft->hybrid_flags & TCP_HYBRID_PACING_SETMSS) == 0)) { /* Lets set in a smaller mss possibly here to match our rate-cap */ uint32_t orig_max; orig_max = rack->r_ctl.rc_pace_max_segs; rack->r_ctl.rc_last_sft->hybrid_flags |= TCP_HYBRID_PACING_SETMSS; rack->r_ctl.rc_pace_max_segs = rack_get_pacing_len(rack, rack->r_ctl.bw_rate_cap, ctf_fixed_maxseg(rack->rc_tp)); rack_log_type_pacing_sizes(rack->rc_tp, rack, rack->r_ctl.client_suggested_maxseg, orig_max, __LINE__, 5); } #endif *capped = 1; *bw = rack->r_ctl.bw_rate_cap; rack_log_hybrid_bw(rack, rack->rc_tp->snd_max, *bw, 0, 0, HYBRID_LOG_RATE_CAP, 1, NULL, __LINE__); } } static uint64_t rack_get_gp_est(struct tcp_rack *rack) { uint64_t bw, lt_bw, ret_bw; if (rack->rc_gp_filled == 0) { /* * We have yet no b/w measurement, * if we have a user set initial bw * return it. If we don't have that and * we have an srtt, use the tcp IW (10) to * calculate a fictional b/w over the SRTT * which is more or less a guess. Note * we don't use our IW from rack on purpose * so if we have like IW=30, we are not * calculating a "huge" b/w. */ uint64_t srtt; lt_bw = rack_get_lt_bw(rack); if (lt_bw) { /* * No goodput bw but a long-term b/w does exist * lets use that. */ ret_bw = lt_bw; goto compensate; } if (rack->r_ctl.init_rate) return (rack->r_ctl.init_rate); /* Ok lets come up with the IW guess, if we have a srtt */ if (rack->rc_tp->t_srtt == 0) { /* * Go with old pacing method * i.e. burst mitigation only. */ return (0); } /* Ok lets get the initial TCP win (not racks) */ bw = tcp_compute_initwnd(tcp_maxseg(rack->rc_tp)); srtt = (uint64_t)rack->rc_tp->t_srtt; bw *= (uint64_t)USECS_IN_SECOND; bw /= srtt; ret_bw = bw; goto compensate; } if (rack->r_ctl.num_measurements >= RACK_REQ_AVG) { /* Averaging is done, we can return the value */ bw = rack->r_ctl.gp_bw; } else { /* Still doing initial average must calculate */ bw = rack->r_ctl.gp_bw / max(rack->r_ctl.num_measurements, 1); } lt_bw = rack_get_lt_bw(rack); if (lt_bw == 0) { /* If we don't have one then equate it to the gp_bw */ lt_bw = rack->r_ctl.gp_bw; } if ((rack->r_cwnd_was_clamped == 1) && (rack->r_clamped_gets_lower > 0)){ /* if clamped take the lowest */ if (lt_bw < bw) ret_bw = lt_bw; else ret_bw = bw; } else { /* If not set for clamped to get lowest, take the highest */ if (lt_bw > bw) ret_bw = lt_bw; else ret_bw = bw; } /* * Now lets compensate based on the TCP/IP overhead. Our * Goodput estimate does not include this so we must pace out * a bit faster since our pacing calculations do. The pacing * calculations use the base ETHERNET_SEGMENT_SIZE and the segsiz * we are using to do this, so we do that here in the opposite * direction as well. This means that if we are tunneled and the * segsiz is say 1200 bytes we will get quite a boost, but its * compensated for in the pacing time the opposite way. */ compensate: ret_bw = rack_compensate_for_linerate(rack, ret_bw); return(ret_bw); } static uint64_t rack_get_bw(struct tcp_rack *rack) { uint64_t bw; if (rack->use_fixed_rate) { /* Return the fixed pacing rate */ return (rack_get_fixed_pacing_bw(rack)); } bw = rack_get_gp_est(rack); return (bw); } static uint16_t rack_get_output_gain(struct tcp_rack *rack, struct rack_sendmap *rsm) { if (rack->use_fixed_rate) { return (100); } else if (rack->in_probe_rtt && (rsm == NULL)) return (rack->r_ctl.rack_per_of_gp_probertt); else if ((IN_FASTRECOVERY(rack->rc_tp->t_flags) && rack->r_ctl.rack_per_of_gp_rec)) { if (rsm) { /* a retransmission always use the recovery rate */ return (rack->r_ctl.rack_per_of_gp_rec); } else if (rack->rack_rec_nonrxt_use_cr) { /* Directed to use the configured rate */ goto configured_rate; } else if (rack->rack_no_prr && (rack->r_ctl.rack_per_of_gp_rec > 100)) { /* No PRR, lets just use the b/w estimate only */ return (100); } else { /* * Here we may have a non-retransmit but we * have no overrides, so just use the recovery * rate (prr is in effect). */ return (rack->r_ctl.rack_per_of_gp_rec); } } configured_rate: /* For the configured rate we look at our cwnd vs the ssthresh */ if (rack->r_ctl.cwnd_to_use < rack->rc_tp->snd_ssthresh) return (rack->r_ctl.rack_per_of_gp_ss); else return (rack->r_ctl.rack_per_of_gp_ca); } static void rack_log_dsack_event(struct tcp_rack *rack, uint8_t mod, uint32_t flex4, uint32_t flex5, uint32_t flex6) { /* * Types of logs (mod value) * 1 = dsack_persists reduced by 1 via T-O or fast recovery exit. * 2 = a dsack round begins, persist is reset to 16. * 3 = a dsack round ends * 4 = Dsack option increases rack rtt flex5 is the srtt input, flex6 is thresh * 5 = Socket option set changing the control flags rc_rack_tmr_std_based, rc_rack_use_dsack * 6 = Final rack rtt, flex4 is srtt and flex6 is final limited thresh. */ if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log, 0, sizeof(log)); log.u_bbr.flex1 = rack->rc_rack_tmr_std_based; log.u_bbr.flex1 <<= 1; log.u_bbr.flex1 |= rack->rc_rack_use_dsack; log.u_bbr.flex1 <<= 1; log.u_bbr.flex1 |= rack->rc_dsack_round_seen; log.u_bbr.flex2 = rack->r_ctl.dsack_round_end; log.u_bbr.flex3 = rack->r_ctl.num_dsack; log.u_bbr.flex4 = flex4; log.u_bbr.flex5 = flex5; log.u_bbr.flex6 = flex6; log.u_bbr.flex7 = rack->r_ctl.dsack_persist; log.u_bbr.flex8 = mod; log.u_bbr.timeStamp = tcp_get_usecs(&tv); TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, RACK_DSACK_HANDLING, 0, 0, &log, false, &tv); } } static void rack_log_hdwr_pacing(struct tcp_rack *rack, uint64_t rate, uint64_t hw_rate, int line, int error, uint16_t mod) { if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; const struct ifnet *ifp; memset(&log, 0, sizeof(log)); log.u_bbr.flex1 = ((hw_rate >> 32) & 0x00000000ffffffff); log.u_bbr.flex2 = (hw_rate & 0x00000000ffffffff); if (rack->r_ctl.crte) { ifp = rack->r_ctl.crte->ptbl->rs_ifp; } else if (rack->rc_inp->inp_route.ro_nh && rack->rc_inp->inp_route.ro_nh->nh_ifp) { ifp = rack->rc_inp->inp_route.ro_nh->nh_ifp; } else ifp = NULL; if (ifp) { log.u_bbr.flex3 = (((uint64_t)ifp >> 32) & 0x00000000ffffffff); log.u_bbr.flex4 = ((uint64_t)ifp & 0x00000000ffffffff); } log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.bw_inuse = rate; log.u_bbr.flex5 = line; log.u_bbr.flex6 = error; log.u_bbr.flex7 = mod; log.u_bbr.applimited = rack->r_ctl.rc_pace_max_segs; log.u_bbr.flex8 = rack->use_fixed_rate; log.u_bbr.flex8 <<= 1; log.u_bbr.flex8 |= rack->rack_hdrw_pacing; log.u_bbr.pkts_out = rack->rc_tp->t_maxseg; log.u_bbr.delRate = rack->r_ctl.crte_prev_rate; if (rack->r_ctl.crte) log.u_bbr.cur_del_rate = rack->r_ctl.crte->rate; else log.u_bbr.cur_del_rate = 0; log.u_bbr.rttProp = rack->r_ctl.last_hw_bw_req; TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, BBR_LOG_HDWR_PACE, 0, 0, &log, false, &tv); } } static uint64_t rack_get_output_bw(struct tcp_rack *rack, uint64_t bw, struct rack_sendmap *rsm, int *capped) { /* * We allow rack_per_of_gp_xx to dictate our bw rate we want. */ uint64_t bw_est, high_rate; uint64_t gain; if ((rack->r_pacing_discount == 0) || (rack_full_buffer_discount == 0)) { /* * No buffer level based discount from client buffer * level is enabled or the feature is disabled. */ gain = (uint64_t)rack_get_output_gain(rack, rsm); bw_est = bw * gain; bw_est /= (uint64_t)100; } else { /* * We have a discount in place apply it with * just a 100% gain (we get no boost if the buffer * is full). */ uint64_t discount; discount = bw * (uint64_t)(rack_full_buffer_discount * rack->r_ctl.pacing_discount_amm); discount /= 100; /* What %% of the b/w do we discount */ bw_est = bw - discount; } /* Never fall below the minimum (def 64kbps) */ if (bw_est < RACK_MIN_BW) bw_est = RACK_MIN_BW; if (rack->r_rack_hw_rate_caps) { /* Rate caps are in place */ if (rack->r_ctl.crte != NULL) { /* We have a hdwr rate already */ high_rate = tcp_hw_highest_rate(rack->r_ctl.crte); if (bw_est >= high_rate) { /* We are capping bw at the highest rate table entry */ if (rack_hw_rate_cap_per && (((high_rate * (100 + rack_hw_rate_cap_per)) / 100) < bw_est)) { rack->r_rack_hw_rate_caps = 0; goto done; } rack_log_hdwr_pacing(rack, bw_est, high_rate, __LINE__, 0, 3); bw_est = high_rate; if (capped) *capped = 1; } } else if ((rack->rack_hdrw_pacing == 0) && (rack->rack_hdw_pace_ena) && (rack->rack_attempt_hdwr_pace == 0) && (rack->rc_inp->inp_route.ro_nh != NULL) && (rack->rc_inp->inp_route.ro_nh->nh_ifp != NULL)) { /* * Special case, we have not yet attempted hardware * pacing, and yet we may, when we do, find out if we are * above the highest rate. We need to know the maxbw for the interface * in question (if it supports ratelimiting). We get back * a 0, if the interface is not found in the RL lists. */ high_rate = tcp_hw_highest_rate_ifp(rack->rc_inp->inp_route.ro_nh->nh_ifp, rack->rc_inp); if (high_rate) { /* Yep, we have a rate is it above this rate? */ if (bw_est > high_rate) { bw_est = high_rate; if (capped) *capped = 1; } } } } done: return (bw_est); } static void rack_log_retran_reason(struct tcp_rack *rack, struct rack_sendmap *rsm, uint32_t tsused, uint32_t thresh, int mod) { if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; if (rack->sack_attack_disable > 0) goto log_anyway; if ((mod != 1) && (rack_verbose_logging == 0)) { /* * We get 3 values currently for mod * 1 - We are retransmitting and this tells the reason. * 2 - We are clearing a dup-ack count. * 3 - We are incrementing a dup-ack count. * * The clear/increment are only logged * if you have BBverbose on. */ return; } log_anyway: memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.flex1 = tsused; log.u_bbr.flex2 = thresh; log.u_bbr.flex3 = rsm->r_flags; log.u_bbr.flex4 = rsm->r_dupack; log.u_bbr.flex5 = rsm->r_start; log.u_bbr.flex6 = rsm->r_end; log.u_bbr.flex8 = mod; log.u_bbr.inhpts = tcp_in_hpts(rack->rc_tp); log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); log.u_bbr.pkts_out = rack->r_ctl.rc_out_at_rto; log.u_bbr.delivered = rack->r_ctl.rc_snd_max_at_rto; log.u_bbr.pacing_gain = rack->r_must_retran; TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, BBR_LOG_SETTINGS_CHG, 0, 0, &log, false, &tv); } } static void rack_log_to_start(struct tcp_rack *rack, uint32_t cts, uint32_t to, int32_t slot, uint8_t which) { if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.flex1 = rack->rc_tp->t_srtt; log.u_bbr.flex2 = to; log.u_bbr.flex3 = rack->r_ctl.rc_hpts_flags; log.u_bbr.flex4 = slot; log.u_bbr.flex5 = rack->rc_tp->t_hpts_slot; log.u_bbr.flex6 = rack->rc_tp->t_rxtcur; log.u_bbr.flex7 = rack->rc_in_persist; log.u_bbr.flex8 = which; if (rack->rack_no_prr) log.u_bbr.pkts_out = 0; else log.u_bbr.pkts_out = rack->r_ctl.rc_prr_sndcnt; log.u_bbr.inhpts = tcp_in_hpts(rack->rc_tp); log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); log.u_bbr.pkts_out = rack->r_ctl.rc_out_at_rto; log.u_bbr.delivered = rack->r_ctl.rc_snd_max_at_rto; log.u_bbr.pacing_gain = rack->r_must_retran; log.u_bbr.cwnd_gain = rack->rack_deferred_inited; log.u_bbr.pkt_epoch = rack->rc_has_collapsed; log.u_bbr.lt_epoch = rack->rc_tp->t_rxtshift; log.u_bbr.lost = rack_rto_min; log.u_bbr.epoch = rack->r_ctl.roundends; TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, BBR_LOG_TIMERSTAR, 0, 0, &log, false, &tv); } } static void rack_log_to_event(struct tcp_rack *rack, int32_t to_num, struct rack_sendmap *rsm) { if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.inhpts = tcp_in_hpts(rack->rc_tp); log.u_bbr.flex8 = to_num; log.u_bbr.flex1 = rack->r_ctl.rc_rack_min_rtt; log.u_bbr.flex2 = rack->rc_rack_rtt; if (rsm == NULL) log.u_bbr.flex3 = 0; else log.u_bbr.flex3 = rsm->r_end - rsm->r_start; if (rack->rack_no_prr) log.u_bbr.flex5 = 0; else log.u_bbr.flex5 = rack->r_ctl.rc_prr_sndcnt; log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); log.u_bbr.pkts_out = rack->r_ctl.rc_out_at_rto; log.u_bbr.delivered = rack->r_ctl.rc_snd_max_at_rto; log.u_bbr.pacing_gain = rack->r_must_retran; TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, BBR_LOG_RTO, 0, 0, &log, false, &tv); } } static void rack_log_map_chg(struct tcpcb *tp, struct tcp_rack *rack, struct rack_sendmap *prev, struct rack_sendmap *rsm, struct rack_sendmap *next, int flag, uint32_t th_ack, int line) { if (rack_verbose_logging && tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.flex8 = flag; log.u_bbr.inhpts = tcp_in_hpts(rack->rc_tp); log.u_bbr.cur_del_rate = (uint64_t)prev; log.u_bbr.delRate = (uint64_t)rsm; log.u_bbr.rttProp = (uint64_t)next; log.u_bbr.flex7 = 0; if (prev) { log.u_bbr.flex1 = prev->r_start; log.u_bbr.flex2 = prev->r_end; log.u_bbr.flex7 |= 0x4; } if (rsm) { log.u_bbr.flex3 = rsm->r_start; log.u_bbr.flex4 = rsm->r_end; log.u_bbr.flex7 |= 0x2; } if (next) { log.u_bbr.flex5 = next->r_start; log.u_bbr.flex6 = next->r_end; log.u_bbr.flex7 |= 0x1; } log.u_bbr.applimited = line; log.u_bbr.pkts_out = th_ack; log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); if (rack->rack_no_prr) log.u_bbr.lost = 0; else log.u_bbr.lost = rack->r_ctl.rc_prr_sndcnt; TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, TCP_LOG_MAPCHG, 0, 0, &log, false, &tv); } } static void rack_log_rtt_upd(struct tcpcb *tp, struct tcp_rack *rack, uint32_t t, uint32_t len, struct rack_sendmap *rsm, int conf) { if (tcp_bblogging_on(tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.inhpts = tcp_in_hpts(rack->rc_tp); log.u_bbr.flex1 = t; log.u_bbr.flex2 = len; log.u_bbr.flex3 = rack->r_ctl.rc_rack_min_rtt; log.u_bbr.flex4 = rack->r_ctl.rack_rs.rs_rtt_lowest; log.u_bbr.flex5 = rack->r_ctl.rack_rs.rs_rtt_highest; log.u_bbr.flex6 = rack->r_ctl.rack_rs.rs_us_rtrcnt; log.u_bbr.flex7 = conf; log.u_bbr.rttProp = (uint64_t)rack->r_ctl.rack_rs.rs_rtt_tot; log.u_bbr.flex8 = rack->r_ctl.rc_rate_sample_method; log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.delivered = rack->r_ctl.rack_rs.rs_us_rtrcnt; log.u_bbr.pkts_out = rack->r_ctl.rack_rs.rs_flags; log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); if (rsm) { log.u_bbr.pkt_epoch = rsm->r_start; log.u_bbr.lost = rsm->r_end; log.u_bbr.cwnd_gain = rsm->r_rtr_cnt; /* We loose any upper of the 24 bits */ log.u_bbr.pacing_gain = (uint16_t)rsm->r_flags; } else { /* Its a SYN */ log.u_bbr.pkt_epoch = rack->rc_tp->iss; log.u_bbr.lost = 0; log.u_bbr.cwnd_gain = 0; log.u_bbr.pacing_gain = 0; } /* Write out general bits of interest rrs here */ log.u_bbr.use_lt_bw = rack->rc_highly_buffered; log.u_bbr.use_lt_bw <<= 1; log.u_bbr.use_lt_bw |= rack->forced_ack; log.u_bbr.use_lt_bw <<= 1; log.u_bbr.use_lt_bw |= rack->rc_gp_dyn_mul; log.u_bbr.use_lt_bw <<= 1; log.u_bbr.use_lt_bw |= rack->in_probe_rtt; log.u_bbr.use_lt_bw <<= 1; log.u_bbr.use_lt_bw |= rack->measure_saw_probe_rtt; log.u_bbr.use_lt_bw <<= 1; log.u_bbr.use_lt_bw |= rack->app_limited_needs_set; log.u_bbr.use_lt_bw <<= 1; log.u_bbr.use_lt_bw |= rack->rc_gp_filled; log.u_bbr.use_lt_bw <<= 1; log.u_bbr.use_lt_bw |= rack->rc_dragged_bottom; log.u_bbr.applimited = rack->r_ctl.rc_target_probertt_flight; log.u_bbr.epoch = rack->r_ctl.rc_time_probertt_starts; log.u_bbr.lt_epoch = rack->r_ctl.rc_time_probertt_entered; log.u_bbr.cur_del_rate = rack->r_ctl.rc_lower_rtt_us_cts; log.u_bbr.delRate = rack->r_ctl.rc_gp_srtt; log.u_bbr.bw_inuse = tcp_tv_to_usectick(&rack->r_ctl.act_rcv_time); log.u_bbr.bw_inuse <<= 32; if (rsm) log.u_bbr.bw_inuse |= ((uint32_t)rsm->r_tim_lastsent[(rsm->r_rtr_cnt-1)]); TCP_LOG_EVENTP(tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, BBR_LOG_BBRRTT, 0, 0, &log, false, &tv); } } static void rack_log_rtt_sample(struct tcp_rack *rack, uint32_t rtt) { /* * Log the rtt sample we are * applying to the srtt algorithm in * useconds. */ if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; /* Convert our ms to a microsecond */ memset(&log, 0, sizeof(log)); log.u_bbr.flex1 = rtt; log.u_bbr.flex2 = rack->r_ctl.ack_count; log.u_bbr.flex3 = rack->r_ctl.sack_count; log.u_bbr.flex4 = rack->r_ctl.sack_noextra_move; log.u_bbr.flex5 = rack->r_ctl.sack_moved_extra; log.u_bbr.flex6 = rack->rc_tp->t_rxtcur; log.u_bbr.flex7 = 1; log.u_bbr.flex8 = rack->sack_attack_disable; log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); log.u_bbr.pkts_out = rack->r_ctl.rc_out_at_rto; log.u_bbr.delivered = rack->r_ctl.rc_snd_max_at_rto; log.u_bbr.pacing_gain = rack->r_must_retran; /* * We capture in delRate the upper 32 bits as * the confidence level we had declared, and the * lower 32 bits as the actual RTT using the arrival * timestamp. */ log.u_bbr.delRate = rack->r_ctl.rack_rs.confidence; log.u_bbr.delRate <<= 32; log.u_bbr.delRate |= rack->r_ctl.rack_rs.rs_us_rtt; /* Lets capture all the things that make up t_rtxcur */ log.u_bbr.applimited = rack_rto_min; log.u_bbr.epoch = rack_rto_max; log.u_bbr.lt_epoch = rack->r_ctl.timer_slop; log.u_bbr.lost = rack_rto_min; log.u_bbr.pkt_epoch = TICKS_2_USEC(tcp_rexmit_slop); log.u_bbr.rttProp = RACK_REXMTVAL(rack->rc_tp); log.u_bbr.bw_inuse = rack->r_ctl.act_rcv_time.tv_sec; log.u_bbr.bw_inuse *= HPTS_USEC_IN_SEC; log.u_bbr.bw_inuse += rack->r_ctl.act_rcv_time.tv_usec; TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, TCP_LOG_RTT, 0, 0, &log, false, &tv); } } static void rack_log_rtt_sample_calc(struct tcp_rack *rack, uint32_t rtt, uint32_t send_time, uint32_t ack_time, int where) { if (rack_verbose_logging && tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; /* Convert our ms to a microsecond */ memset(&log, 0, sizeof(log)); log.u_bbr.flex1 = rtt; log.u_bbr.flex2 = send_time; log.u_bbr.flex3 = ack_time; log.u_bbr.flex4 = where; log.u_bbr.flex7 = 2; log.u_bbr.timeStamp = tcp_get_usecs(&tv); TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, TCP_LOG_RTT, 0, 0, &log, false, &tv); } } static void rack_log_rtt_sendmap(struct tcp_rack *rack, uint32_t idx, uint64_t tsv, uint32_t tsecho) { if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; /* Convert our ms to a microsecond */ memset(&log, 0, sizeof(log)); log.u_bbr.flex1 = idx; log.u_bbr.flex2 = rack_ts_to_msec(tsv); log.u_bbr.flex3 = tsecho; log.u_bbr.flex7 = 3; log.u_bbr.rttProp = tsv; log.u_bbr.timeStamp = tcp_get_usecs(&tv); TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, TCP_LOG_RTT, 0, 0, &log, false, &tv); } } static inline void rack_log_progress_event(struct tcp_rack *rack, struct tcpcb *tp, uint32_t tick, int event, int line) { if (rack_verbose_logging && tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.inhpts = tcp_in_hpts(rack->rc_tp); log.u_bbr.flex1 = line; log.u_bbr.flex2 = tick; log.u_bbr.flex3 = tp->t_maxunacktime; log.u_bbr.flex4 = tp->t_acktime; log.u_bbr.flex8 = event; log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); log.u_bbr.pkts_out = rack->r_ctl.rc_out_at_rto; log.u_bbr.delivered = rack->r_ctl.rc_snd_max_at_rto; log.u_bbr.pacing_gain = rack->r_must_retran; TCP_LOG_EVENTP(tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, BBR_LOG_PROGRESS, 0, 0, &log, false, &tv); } } static void rack_log_type_bbrsnd(struct tcp_rack *rack, uint32_t len, uint32_t slot, uint32_t cts, struct timeval *tv, int line) { if (rack_verbose_logging && tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.inhpts = tcp_in_hpts(rack->rc_tp); log.u_bbr.flex1 = slot; if (rack->rack_no_prr) log.u_bbr.flex2 = 0; else log.u_bbr.flex2 = rack->r_ctl.rc_prr_sndcnt; log.u_bbr.flex4 = rack->r_ctl.rc_hpts_flags; log.u_bbr.flex5 = rack->r_ctl.ack_during_sd; log.u_bbr.flex6 = line; log.u_bbr.flex7 = (0x0000ffff & rack->r_ctl.rc_hpts_flags); log.u_bbr.flex8 = rack->rc_in_persist; log.u_bbr.timeStamp = cts; log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); log.u_bbr.pkts_out = rack->r_ctl.rc_out_at_rto; log.u_bbr.delivered = rack->r_ctl.rc_snd_max_at_rto; log.u_bbr.pacing_gain = rack->r_must_retran; TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, BBR_LOG_BBRSND, 0, 0, &log, false, tv); } } static void rack_log_doseg_done(struct tcp_rack *rack, uint32_t cts, int32_t nxt_pkt, int32_t did_out, int way_out, int nsegs) { if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log, 0, sizeof(log)); log.u_bbr.flex1 = did_out; log.u_bbr.flex2 = nxt_pkt; log.u_bbr.flex3 = way_out; log.u_bbr.flex4 = rack->r_ctl.rc_hpts_flags; if (rack->rack_no_prr) log.u_bbr.flex5 = 0; else log.u_bbr.flex5 = rack->r_ctl.rc_prr_sndcnt; log.u_bbr.flex6 = nsegs; log.u_bbr.applimited = rack->r_ctl.rc_pace_min_segs; log.u_bbr.flex7 = rack->rc_ack_can_sendout_data; /* Do we have ack-can-send set */ log.u_bbr.flex7 <<= 1; log.u_bbr.flex7 |= rack->r_fast_output; /* is fast output primed */ log.u_bbr.flex7 <<= 1; log.u_bbr.flex7 |= rack->r_wanted_output; /* Do we want output */ log.u_bbr.flex8 = rack->rc_in_persist; log.u_bbr.inhpts = tcp_in_hpts(rack->rc_tp); log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); log.u_bbr.use_lt_bw = rack->r_ent_rec_ns; log.u_bbr.use_lt_bw <<= 1; log.u_bbr.use_lt_bw |= rack->r_might_revert; log.u_bbr.pkts_out = rack->r_ctl.rc_out_at_rto; log.u_bbr.delivered = rack->r_ctl.rc_snd_max_at_rto; log.u_bbr.pacing_gain = rack->r_must_retran; TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, BBR_LOG_DOSEG_DONE, 0, 0, &log, false, &tv); } } static void rack_log_type_pacing_sizes(struct tcpcb *tp, struct tcp_rack *rack, uint32_t arg1, uint32_t arg2, uint32_t arg3, uint8_t frm) { if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log, 0, sizeof(log)); log.u_bbr.flex1 = rack->r_ctl.rc_pace_min_segs; log.u_bbr.flex3 = rack->r_ctl.rc_pace_max_segs; log.u_bbr.flex4 = arg1; log.u_bbr.flex5 = arg2; log.u_bbr.flex7 = rack->r_ctl.rc_user_set_min_segs; log.u_bbr.flex6 = arg3; log.u_bbr.flex8 = frm; log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); log.u_bbr.pkts_out = rack->r_ctl.rc_out_at_rto; log.u_bbr.applimited = rack->r_ctl.rc_sacked; log.u_bbr.delivered = rack->r_ctl.rc_snd_max_at_rto; log.u_bbr.pacing_gain = rack->r_must_retran; TCP_LOG_EVENTP(tp, NULL, &tptosocket(tp)->so_rcv, &tptosocket(tp)->so_snd, TCP_HDWR_PACE_SIZE, 0, 0, &log, false, &tv); } } static void rack_log_type_just_return(struct tcp_rack *rack, uint32_t cts, uint32_t tlen, uint32_t slot, uint8_t hpts_calling, int reason, uint32_t cwnd_to_use) { if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.inhpts = tcp_in_hpts(rack->rc_tp); log.u_bbr.flex1 = slot; log.u_bbr.flex2 = rack->r_ctl.rc_hpts_flags; log.u_bbr.flex4 = reason; if (rack->rack_no_prr) log.u_bbr.flex5 = 0; else log.u_bbr.flex5 = rack->r_ctl.rc_prr_sndcnt; log.u_bbr.flex7 = hpts_calling; log.u_bbr.flex8 = rack->rc_in_persist; log.u_bbr.lt_epoch = cwnd_to_use; log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); log.u_bbr.pkts_out = rack->r_ctl.rc_out_at_rto; log.u_bbr.delivered = rack->r_ctl.rc_snd_max_at_rto; log.u_bbr.pacing_gain = rack->r_must_retran; log.u_bbr.cwnd_gain = rack->rc_has_collapsed; TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, BBR_LOG_JUSTRET, 0, tlen, &log, false, &tv); } } static void rack_log_to_cancel(struct tcp_rack *rack, int32_t hpts_removed, int line, uint32_t us_cts, struct timeval *tv, uint32_t flags_on_entry) { if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.inhpts = tcp_in_hpts(rack->rc_tp); log.u_bbr.flex1 = line; log.u_bbr.flex2 = rack->r_ctl.rc_last_output_to; log.u_bbr.flex3 = flags_on_entry; log.u_bbr.flex4 = us_cts; if (rack->rack_no_prr) log.u_bbr.flex5 = 0; else log.u_bbr.flex5 = rack->r_ctl.rc_prr_sndcnt; log.u_bbr.flex6 = rack->rc_tp->t_rxtcur; log.u_bbr.flex7 = hpts_removed; log.u_bbr.flex8 = 1; log.u_bbr.applimited = rack->r_ctl.rc_hpts_flags; log.u_bbr.timeStamp = us_cts; log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); log.u_bbr.pkts_out = rack->r_ctl.rc_out_at_rto; log.u_bbr.delivered = rack->r_ctl.rc_snd_max_at_rto; log.u_bbr.pacing_gain = rack->r_must_retran; TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, BBR_LOG_TIMERCANC, 0, 0, &log, false, tv); } } static void rack_log_alt_to_to_cancel(struct tcp_rack *rack, uint32_t flex1, uint32_t flex2, uint32_t flex3, uint32_t flex4, uint32_t flex5, uint32_t flex6, uint16_t flex7, uint8_t mod) { if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; if (mod == 1) { /* No you can't use 1, its for the real to cancel */ return; } memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.flex1 = flex1; log.u_bbr.flex2 = flex2; log.u_bbr.flex3 = flex3; log.u_bbr.flex4 = flex4; log.u_bbr.flex5 = flex5; log.u_bbr.flex6 = flex6; log.u_bbr.flex7 = flex7; log.u_bbr.flex8 = mod; TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, BBR_LOG_TIMERCANC, 0, 0, &log, false, &tv); } } static void rack_log_to_processing(struct tcp_rack *rack, uint32_t cts, int32_t ret, int32_t timers) { if (rack_verbose_logging && tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.flex1 = timers; log.u_bbr.flex2 = ret; log.u_bbr.flex3 = rack->r_ctl.rc_timer_exp; log.u_bbr.flex4 = rack->r_ctl.rc_hpts_flags; log.u_bbr.flex5 = cts; if (rack->rack_no_prr) log.u_bbr.flex6 = 0; else log.u_bbr.flex6 = rack->r_ctl.rc_prr_sndcnt; log.u_bbr.pkts_out = rack->r_ctl.rc_out_at_rto; log.u_bbr.delivered = rack->r_ctl.rc_snd_max_at_rto; log.u_bbr.pacing_gain = rack->r_must_retran; log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, BBR_LOG_TO_PROCESS, 0, 0, &log, false, &tv); } } static void rack_log_to_prr(struct tcp_rack *rack, int frm, int orig_cwnd, int line) { if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.flex1 = rack->r_ctl.rc_prr_out; log.u_bbr.flex2 = rack->r_ctl.rc_prr_recovery_fs; if (rack->rack_no_prr) log.u_bbr.flex3 = 0; else log.u_bbr.flex3 = rack->r_ctl.rc_prr_sndcnt; log.u_bbr.flex4 = rack->r_ctl.rc_prr_delivered; log.u_bbr.flex5 = rack->r_ctl.rc_sacked; log.u_bbr.flex6 = rack->r_ctl.rc_holes_rxt; log.u_bbr.flex7 = line; log.u_bbr.flex8 = frm; log.u_bbr.pkts_out = orig_cwnd; log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); log.u_bbr.use_lt_bw = rack->r_ent_rec_ns; log.u_bbr.use_lt_bw <<= 1; log.u_bbr.use_lt_bw |= rack->r_might_revert; TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, BBR_LOG_BBRUPD, 0, 0, &log, false, &tv); } } #ifdef TCP_SAD_DETECTION static void rack_log_sad(struct tcp_rack *rack, int event) { if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.flex1 = rack->r_ctl.sack_count; log.u_bbr.flex2 = rack->r_ctl.ack_count; log.u_bbr.flex3 = rack->r_ctl.sack_moved_extra; log.u_bbr.flex4 = rack->r_ctl.sack_noextra_move; log.u_bbr.flex5 = rack->r_ctl.rc_num_maps_alloced; log.u_bbr.flex6 = tcp_sack_to_ack_thresh; log.u_bbr.pkts_out = tcp_sack_to_move_thresh; log.u_bbr.lt_epoch = (tcp_force_detection << 8); log.u_bbr.lt_epoch |= rack->do_detection; log.u_bbr.applimited = tcp_map_minimum; log.u_bbr.flex7 = rack->sack_attack_disable; log.u_bbr.flex8 = event; log.u_bbr.bbr_state = rack->rc_suspicious; log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); log.u_bbr.delivered = tcp_sad_decay_val; TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, TCP_SAD_DETECT, 0, 0, &log, false, &tv); } } #endif static void rack_counter_destroy(void) { counter_u64_free(rack_total_bytes); counter_u64_free(rack_fto_send); counter_u64_free(rack_fto_rsm_send); counter_u64_free(rack_nfto_resend); counter_u64_free(rack_hw_pace_init_fail); counter_u64_free(rack_hw_pace_lost); counter_u64_free(rack_non_fto_send); counter_u64_free(rack_extended_rfo); counter_u64_free(rack_ack_total); counter_u64_free(rack_express_sack); counter_u64_free(rack_sack_total); counter_u64_free(rack_move_none); counter_u64_free(rack_move_some); counter_u64_free(rack_sack_attacks_detected); counter_u64_free(rack_sack_attacks_reversed); counter_u64_free(rack_sack_attacks_suspect); counter_u64_free(rack_sack_used_next_merge); counter_u64_free(rack_sack_used_prev_merge); counter_u64_free(rack_tlp_tot); counter_u64_free(rack_tlp_newdata); counter_u64_free(rack_tlp_retran); counter_u64_free(rack_tlp_retran_bytes); counter_u64_free(rack_to_tot); counter_u64_free(rack_saw_enobuf); counter_u64_free(rack_saw_enobuf_hw); counter_u64_free(rack_saw_enetunreach); counter_u64_free(rack_hot_alloc); counter_u64_free(rack_to_alloc); counter_u64_free(rack_to_alloc_hard); counter_u64_free(rack_to_alloc_emerg); counter_u64_free(rack_to_alloc_limited); counter_u64_free(rack_alloc_limited_conns); counter_u64_free(rack_split_limited); counter_u64_free(rack_multi_single_eq); counter_u64_free(rack_rxt_clamps_cwnd); counter_u64_free(rack_rxt_clamps_cwnd_uniq); counter_u64_free(rack_proc_non_comp_ack); counter_u64_free(rack_sack_proc_all); counter_u64_free(rack_sack_proc_restart); counter_u64_free(rack_sack_proc_short); counter_u64_free(rack_sack_skipped_acked); counter_u64_free(rack_sack_splits); counter_u64_free(rack_input_idle_reduces); counter_u64_free(rack_collapsed_win); counter_u64_free(rack_collapsed_win_rxt); counter_u64_free(rack_collapsed_win_rxt_bytes); counter_u64_free(rack_collapsed_win_seen); counter_u64_free(rack_try_scwnd); counter_u64_free(rack_persists_sends); counter_u64_free(rack_persists_acks); counter_u64_free(rack_persists_loss); counter_u64_free(rack_persists_lost_ends); #ifdef INVARIANTS counter_u64_free(rack_adjust_map_bw); #endif COUNTER_ARRAY_FREE(rack_out_size, TCP_MSS_ACCT_SIZE); COUNTER_ARRAY_FREE(rack_opts_arry, RACK_OPTS_SIZE); } static struct rack_sendmap * rack_alloc(struct tcp_rack *rack) { struct rack_sendmap *rsm; /* * First get the top of the list it in * theory is the "hottest" rsm we have, * possibly just freed by ack processing. */ if (rack->rc_free_cnt > rack_free_cache) { rsm = TAILQ_FIRST(&rack->r_ctl.rc_free); TAILQ_REMOVE(&rack->r_ctl.rc_free, rsm, r_tnext); counter_u64_add(rack_hot_alloc, 1); rack->rc_free_cnt--; return (rsm); } /* * Once we get under our free cache we probably * no longer have a "hot" one available. Lets * get one from UMA. */ rsm = uma_zalloc(rack_zone, M_NOWAIT); if (rsm) { rack->r_ctl.rc_num_maps_alloced++; counter_u64_add(rack_to_alloc, 1); return (rsm); } /* * Dig in to our aux rsm's (the last two) since * UMA failed to get us one. */ if (rack->rc_free_cnt) { counter_u64_add(rack_to_alloc_emerg, 1); rsm = TAILQ_FIRST(&rack->r_ctl.rc_free); TAILQ_REMOVE(&rack->r_ctl.rc_free, rsm, r_tnext); rack->rc_free_cnt--; return (rsm); } return (NULL); } static struct rack_sendmap * rack_alloc_full_limit(struct tcp_rack *rack) { if ((V_tcp_map_entries_limit > 0) && (rack->do_detection == 0) && (rack->r_ctl.rc_num_maps_alloced >= V_tcp_map_entries_limit)) { counter_u64_add(rack_to_alloc_limited, 1); if (!rack->alloc_limit_reported) { rack->alloc_limit_reported = 1; counter_u64_add(rack_alloc_limited_conns, 1); } return (NULL); } return (rack_alloc(rack)); } /* wrapper to allocate a sendmap entry, subject to a specific limit */ static struct rack_sendmap * rack_alloc_limit(struct tcp_rack *rack, uint8_t limit_type) { struct rack_sendmap *rsm; if (limit_type) { /* currently there is only one limit type */ if (rack->r_ctl.rc_split_limit > 0 && (rack->do_detection == 0) && rack->r_ctl.rc_num_split_allocs >= rack->r_ctl.rc_split_limit) { counter_u64_add(rack_split_limited, 1); if (!rack->alloc_limit_reported) { rack->alloc_limit_reported = 1; counter_u64_add(rack_alloc_limited_conns, 1); } return (NULL); #ifdef TCP_SAD_DETECTION } else if ((tcp_sad_limit != 0) && (rack->do_detection == 1) && (rack->r_ctl.rc_num_split_allocs >= tcp_sad_limit)) { counter_u64_add(rack_split_limited, 1); if (!rack->alloc_limit_reported) { rack->alloc_limit_reported = 1; counter_u64_add(rack_alloc_limited_conns, 1); } return (NULL); #endif } } /* allocate and mark in the limit type, if set */ rsm = rack_alloc(rack); if (rsm != NULL && limit_type) { rsm->r_limit_type = limit_type; rack->r_ctl.rc_num_split_allocs++; } return (rsm); } static void rack_free_trim(struct tcp_rack *rack) { struct rack_sendmap *rsm; /* * Free up all the tail entries until * we get our list down to the limit. */ while (rack->rc_free_cnt > rack_free_cache) { rsm = TAILQ_LAST(&rack->r_ctl.rc_free, rack_head); TAILQ_REMOVE(&rack->r_ctl.rc_free, rsm, r_tnext); rack->rc_free_cnt--; rack->r_ctl.rc_num_maps_alloced--; uma_zfree(rack_zone, rsm); } } static void rack_free(struct tcp_rack *rack, struct rack_sendmap *rsm) { if (rsm->r_flags & RACK_APP_LIMITED) { if (rack->r_ctl.rc_app_limited_cnt > 0) { rack->r_ctl.rc_app_limited_cnt--; } } if (rsm->r_limit_type) { /* currently there is only one limit type */ rack->r_ctl.rc_num_split_allocs--; } if (rsm == rack->r_ctl.rc_first_appl) { if (rack->r_ctl.rc_app_limited_cnt == 0) rack->r_ctl.rc_first_appl = NULL; else rack->r_ctl.rc_first_appl = tqhash_find(rack->r_ctl.tqh, rsm->r_nseq_appl); } if (rsm == rack->r_ctl.rc_resend) rack->r_ctl.rc_resend = NULL; if (rsm == rack->r_ctl.rc_end_appl) rack->r_ctl.rc_end_appl = NULL; if (rack->r_ctl.rc_tlpsend == rsm) rack->r_ctl.rc_tlpsend = NULL; if (rack->r_ctl.rc_sacklast == rsm) rack->r_ctl.rc_sacklast = NULL; memset(rsm, 0, sizeof(struct rack_sendmap)); /* Make sure we are not going to overrun our count limit of 0xff */ if ((rack->rc_free_cnt + 1) > 0xff) { rack_free_trim(rack); } TAILQ_INSERT_HEAD(&rack->r_ctl.rc_free, rsm, r_tnext); rack->rc_free_cnt++; } static uint32_t rack_get_measure_window(struct tcpcb *tp, struct tcp_rack *rack) { uint64_t srtt, bw, len, tim; uint32_t segsiz, def_len, minl; segsiz = min(ctf_fixed_maxseg(tp), rack->r_ctl.rc_pace_min_segs); def_len = rack_def_data_window * segsiz; if (rack->rc_gp_filled == 0) { /* * We have no measurement (IW is in flight?) so * we can only guess using our data_window sysctl * value (usually 20MSS). */ return (def_len); } /* * Now we have a number of factors to consider. * * 1) We have a desired BDP which is usually * at least 2. * 2) We have a minimum number of rtt's usually 1 SRTT * but we allow it too to be more. * 3) We want to make sure a measurement last N useconds (if * we have set rack_min_measure_usec. * * We handle the first concern here by trying to create a data * window of max(rack_def_data_window, DesiredBDP). The * second concern we handle in not letting the measurement * window end normally until at least the required SRTT's * have gone by which is done further below in * rack_enough_for_measurement(). Finally the third concern * we also handle here by calculating how long that time * would take at the current BW and then return the * max of our first calculation and that length. Note * that if rack_min_measure_usec is 0, we don't deal * with concern 3. Also for both Concern 1 and 3 an * application limited period could end the measurement * earlier. * * So lets calculate the BDP with the "known" b/w using * the SRTT has our rtt and then multiply it by the * goal. */ bw = rack_get_bw(rack); srtt = (uint64_t)tp->t_srtt; len = bw * srtt; len /= (uint64_t)HPTS_USEC_IN_SEC; len *= max(1, rack_goal_bdp); /* Now we need to round up to the nearest MSS */ len = roundup(len, segsiz); if (rack_min_measure_usec) { /* Now calculate our min length for this b/w */ tim = rack_min_measure_usec; minl = (tim * bw) / (uint64_t)HPTS_USEC_IN_SEC; if (minl == 0) minl = 1; minl = roundup(minl, segsiz); if (len < minl) len = minl; } /* * Now if we have a very small window we want * to attempt to get the window that is * as small as possible. This happens on * low b/w connections and we don't want to * span huge numbers of rtt's between measurements. * * We basically include 2 over our "MIN window" so * that the measurement can be shortened (possibly) by * an ack'ed packet. */ if (len < def_len) return (max((uint32_t)len, ((MIN_GP_WIN+2) * segsiz))); else return (max((uint32_t)len, def_len)); } static int rack_enough_for_measurement(struct tcpcb *tp, struct tcp_rack *rack, tcp_seq th_ack, uint8_t *quality) { uint32_t tim, srtts, segsiz; /* * Has enough time passed for the GP measurement to be valid? */ if (SEQ_LT(th_ack, tp->gput_seq)) { /* Not enough bytes yet */ return (0); } if ((tp->snd_max == tp->snd_una) || (th_ack == tp->snd_max)){ /* * All is acked quality of all acked is * usually low or medium, but we in theory could split * all acked into two cases, where you got * a signifigant amount of your window and * where you did not. For now we leave it * but it is something to contemplate in the * future. The danger here is that delayed ack * is effecting the last byte (which is a 50:50 chance). */ *quality = RACK_QUALITY_ALLACKED; return (1); } if (SEQ_GEQ(th_ack, tp->gput_ack)) { /* * We obtained our entire window of data we wanted * no matter if we are in recovery or not then * its ok since expanding the window does not * make things fuzzy (or at least not as much). */ *quality = RACK_QUALITY_HIGH; return (1); } segsiz = min(ctf_fixed_maxseg(tp), rack->r_ctl.rc_pace_min_segs); if (SEQ_LT(th_ack, tp->gput_ack) && ((th_ack - tp->gput_seq) < max(rc_init_window(rack), (MIN_GP_WIN * segsiz)))) { /* Not enough bytes yet */ return (0); } if (rack->r_ctl.rc_first_appl && (SEQ_GEQ(th_ack, rack->r_ctl.rc_first_appl->r_end))) { /* * We are up to the app limited send point * we have to measure irrespective of the time.. */ *quality = RACK_QUALITY_APPLIMITED; return (1); } /* Now what about time? */ srtts = (rack->r_ctl.rc_gp_srtt * rack_min_srtts); tim = tcp_tv_to_usectick(&rack->r_ctl.act_rcv_time) - tp->gput_ts; if ((tim >= srtts) && (IN_RECOVERY(rack->rc_tp->t_flags) == 0)) { /* * We do not allow a measurement if we are in recovery * that would shrink the goodput window we wanted. * This is to prevent cloudyness of when the last send * was actually made. */ *quality = RACK_QUALITY_HIGH; return (1); } /* Nope not even a full SRTT has passed */ return (0); } static void rack_log_timely(struct tcp_rack *rack, uint32_t logged, uint64_t cur_bw, uint64_t low_bnd, uint64_t up_bnd, int line, uint8_t method) { if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log, 0, sizeof(log)); log.u_bbr.flex1 = logged; log.u_bbr.flex2 = rack->rc_gp_timely_inc_cnt; log.u_bbr.flex2 <<= 4; log.u_bbr.flex2 |= rack->rc_gp_timely_dec_cnt; log.u_bbr.flex2 <<= 4; log.u_bbr.flex2 |= rack->rc_gp_incr; log.u_bbr.flex2 <<= 4; log.u_bbr.flex2 |= rack->rc_gp_bwred; log.u_bbr.flex3 = rack->rc_gp_incr; log.u_bbr.flex4 = rack->r_ctl.rack_per_of_gp_ss; log.u_bbr.flex5 = rack->r_ctl.rack_per_of_gp_ca; log.u_bbr.flex6 = rack->r_ctl.rack_per_of_gp_rec; log.u_bbr.flex7 = rack->rc_gp_bwred; log.u_bbr.flex8 = method; log.u_bbr.cur_del_rate = cur_bw; log.u_bbr.delRate = low_bnd; log.u_bbr.bw_inuse = up_bnd; log.u_bbr.rttProp = rack_get_bw(rack); log.u_bbr.pkt_epoch = line; log.u_bbr.pkts_out = rack->r_ctl.rc_rtt_diff; log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); log.u_bbr.epoch = rack->r_ctl.rc_gp_srtt; log.u_bbr.lt_epoch = rack->r_ctl.rc_prev_gp_srtt; log.u_bbr.cwnd_gain = rack->rc_dragged_bottom; log.u_bbr.cwnd_gain <<= 1; log.u_bbr.cwnd_gain |= rack->rc_gp_saw_rec; log.u_bbr.cwnd_gain <<= 1; log.u_bbr.cwnd_gain |= rack->rc_gp_saw_ss; log.u_bbr.cwnd_gain <<= 1; log.u_bbr.cwnd_gain |= rack->rc_gp_saw_ca; log.u_bbr.lost = rack->r_ctl.rc_loss_count; TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, TCP_TIMELY_WORK, 0, 0, &log, false, &tv); } } static int rack_bw_can_be_raised(struct tcp_rack *rack, uint64_t cur_bw, uint64_t last_bw_est, uint16_t mult) { /* * Before we increase we need to know if * the estimate just made was less than * our pacing goal (i.e. (cur_bw * mult) > last_bw_est) * * If we already are pacing at a fast enough * rate to push us faster there is no sense of * increasing. * * We first caculate our actual pacing rate (ss or ca multiplier * times our cur_bw). * * Then we take the last measured rate and multipy by our * maximum pacing overage to give us a max allowable rate. * * If our act_rate is smaller than our max_allowable rate * then we should increase. Else we should hold steady. * */ uint64_t act_rate, max_allow_rate; if (rack_timely_no_stopping) return (1); if ((cur_bw == 0) || (last_bw_est == 0)) { /* * Initial startup case or * everything is acked case. */ rack_log_timely(rack, mult, cur_bw, 0, 0, __LINE__, 9); return (1); } if (mult <= 100) { /* * We can always pace at or slightly above our rate. */ rack_log_timely(rack, mult, cur_bw, 0, 0, __LINE__, 9); return (1); } act_rate = cur_bw * (uint64_t)mult; act_rate /= 100; max_allow_rate = last_bw_est * ((uint64_t)rack_max_per_above + (uint64_t)100); max_allow_rate /= 100; if (act_rate < max_allow_rate) { /* * Here the rate we are actually pacing at * is smaller than 10% above our last measurement. * This means we are pacing below what we would * like to try to achieve (plus some wiggle room). */ rack_log_timely(rack, mult, cur_bw, act_rate, max_allow_rate, __LINE__, 9); return (1); } else { /* * Here we are already pacing at least rack_max_per_above(10%) * what we are getting back. This indicates most likely * that we are being limited (cwnd/rwnd/app) and can't * get any more b/w. There is no sense of trying to * raise up the pacing rate its not speeding us up * and we already are pacing faster than we are getting. */ rack_log_timely(rack, mult, cur_bw, act_rate, max_allow_rate, __LINE__, 8); return (0); } } static void rack_validate_multipliers_at_or_above100(struct tcp_rack *rack) { /* * When we drag bottom, we want to assure * that no multiplier is below 1.0, if so * we want to restore it to at least that. */ if (rack->r_ctl.rack_per_of_gp_rec < 100) { /* This is unlikely we usually do not touch recovery */ rack->r_ctl.rack_per_of_gp_rec = 100; } if (rack->r_ctl.rack_per_of_gp_ca < 100) { rack->r_ctl.rack_per_of_gp_ca = 100; } if (rack->r_ctl.rack_per_of_gp_ss < 100) { rack->r_ctl.rack_per_of_gp_ss = 100; } } static void rack_validate_multipliers_at_or_below_100(struct tcp_rack *rack) { if (rack->r_ctl.rack_per_of_gp_ca > 100) { rack->r_ctl.rack_per_of_gp_ca = 100; } if (rack->r_ctl.rack_per_of_gp_ss > 100) { rack->r_ctl.rack_per_of_gp_ss = 100; } } static void rack_increase_bw_mul(struct tcp_rack *rack, int timely_says, uint64_t cur_bw, uint64_t last_bw_est, int override) { int32_t calc, logged, plus; logged = 0; if (override) { /* * override is passed when we are * loosing b/w and making one last * gasp at trying to not loose out * to a new-reno flow. */ goto extra_boost; } /* In classic timely we boost by 5x if we have 5 increases in a row, lets not */ if (rack->rc_gp_incr && ((rack->rc_gp_timely_inc_cnt + 1) >= RACK_TIMELY_CNT_BOOST)) { /* * Reset and get 5 strokes more before the boost. Note * that the count is 0 based so we have to add one. */ extra_boost: plus = (uint32_t)rack_gp_increase_per * RACK_TIMELY_CNT_BOOST; rack->rc_gp_timely_inc_cnt = 0; } else plus = (uint32_t)rack_gp_increase_per; /* Must be at least 1% increase for true timely increases */ if ((plus < 1) && ((rack->r_ctl.rc_rtt_diff <= 0) || (timely_says <= 0))) plus = 1; if (rack->rc_gp_saw_rec && (rack->rc_gp_no_rec_chg == 0) && rack_bw_can_be_raised(rack, cur_bw, last_bw_est, rack->r_ctl.rack_per_of_gp_rec)) { /* We have been in recovery ding it too */ calc = rack->r_ctl.rack_per_of_gp_rec + plus; if (calc > 0xffff) calc = 0xffff; logged |= 1; rack->r_ctl.rack_per_of_gp_rec = (uint16_t)calc; if (rack->r_ctl.rack_per_upper_bound_ca && (rack->rc_dragged_bottom == 0) && (rack->r_ctl.rack_per_of_gp_rec > rack->r_ctl.rack_per_upper_bound_ca)) rack->r_ctl.rack_per_of_gp_rec = rack->r_ctl.rack_per_upper_bound_ca; } if (rack->rc_gp_saw_ca && (rack->rc_gp_saw_ss == 0) && rack_bw_can_be_raised(rack, cur_bw, last_bw_est, rack->r_ctl.rack_per_of_gp_ca)) { /* In CA */ calc = rack->r_ctl.rack_per_of_gp_ca + plus; if (calc > 0xffff) calc = 0xffff; logged |= 2; rack->r_ctl.rack_per_of_gp_ca = (uint16_t)calc; if (rack->r_ctl.rack_per_upper_bound_ca && (rack->rc_dragged_bottom == 0) && (rack->r_ctl.rack_per_of_gp_ca > rack->r_ctl.rack_per_upper_bound_ca)) rack->r_ctl.rack_per_of_gp_ca = rack->r_ctl.rack_per_upper_bound_ca; } if (rack->rc_gp_saw_ss && rack_bw_can_be_raised(rack, cur_bw, last_bw_est, rack->r_ctl.rack_per_of_gp_ss)) { /* In SS */ calc = rack->r_ctl.rack_per_of_gp_ss + plus; if (calc > 0xffff) calc = 0xffff; rack->r_ctl.rack_per_of_gp_ss = (uint16_t)calc; if (rack->r_ctl.rack_per_upper_bound_ss && (rack->rc_dragged_bottom == 0) && (rack->r_ctl.rack_per_of_gp_ss > rack->r_ctl.rack_per_upper_bound_ss)) rack->r_ctl.rack_per_of_gp_ss = rack->r_ctl.rack_per_upper_bound_ss; logged |= 4; } if (logged && (rack->rc_gp_incr == 0)){ /* Go into increment mode */ rack->rc_gp_incr = 1; rack->rc_gp_timely_inc_cnt = 0; } if (rack->rc_gp_incr && logged && (rack->rc_gp_timely_inc_cnt < RACK_TIMELY_CNT_BOOST)) { rack->rc_gp_timely_inc_cnt++; } rack_log_timely(rack, logged, plus, 0, 0, __LINE__, 1); } static uint32_t rack_get_decrease(struct tcp_rack *rack, uint32_t curper, int32_t rtt_diff) { /*- * norm_grad = rtt_diff / minrtt; * new_per = curper * (1 - B * norm_grad) * * B = rack_gp_decrease_per (default 80%) * rtt_dif = input var current rtt-diff * curper = input var current percentage * minrtt = from rack filter * * In order to do the floating point calculations above we * do an integer conversion. The code looks confusing so let me * translate it into something that use more variables and * is clearer for us humans :) * * uint64_t norm_grad, inverse, reduce_by, final_result; * uint32_t perf; * * norm_grad = (((uint64_t)rtt_diff * 1000000) / * (uint64_t)get_filter_small(&rack->r_ctl.rc_gp_min_rtt)); * inverse = ((uint64_t)rack_gp_decrease * (uint64_t)1000000) * norm_grad; * inverse /= 1000000; * reduce_by = (1000000 - inverse); * final_result = (cur_per * reduce_by) / 1000000; * perf = (uint32_t)final_result; */ uint64_t perf; perf = (((uint64_t)curper * ((uint64_t)1000000 - ((uint64_t)rack_gp_decrease_per * (uint64_t)10000 * (((uint64_t)rtt_diff * (uint64_t)1000000)/ (uint64_t)get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt)))/ (uint64_t)1000000)) / (uint64_t)1000000); if (perf > curper) { /* TSNH */ perf = curper - 1; } return ((uint32_t)perf); } static uint32_t rack_decrease_highrtt(struct tcp_rack *rack, uint32_t curper, uint32_t rtt) { /* * highrttthresh * result = curper * (1 - (B * ( 1 - ------ )) * gp_srtt * * B = rack_gp_decrease_per (default .8 i.e. 80) * highrttthresh = filter_min * rack_gp_rtt_maxmul */ uint64_t perf; uint32_t highrttthresh; highrttthresh = get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt) * rack_gp_rtt_maxmul; perf = (((uint64_t)curper * ((uint64_t)1000000 - ((uint64_t)rack_gp_decrease_per * ((uint64_t)1000000 - ((uint64_t)highrttthresh * (uint64_t)1000000) / (uint64_t)rtt)) / 100)) /(uint64_t)1000000); if (tcp_bblogging_on(rack->rc_tp)) { uint64_t log1; log1 = rtt; log1 <<= 32; log1 |= highrttthresh; rack_log_timely(rack, rack_gp_decrease_per, (uint64_t)curper, log1, perf, __LINE__, 15); } return (perf); } static void rack_decrease_bw_mul(struct tcp_rack *rack, int timely_says, uint32_t rtt, int32_t rtt_diff) { uint64_t logvar, logvar2, logvar3; uint32_t logged, new_per, ss_red, ca_red, rec_red, alt, val; if (rack->rc_gp_incr) { /* Turn off increment counting */ rack->rc_gp_incr = 0; rack->rc_gp_timely_inc_cnt = 0; } ss_red = ca_red = rec_red = 0; logged = 0; /* Calculate the reduction value */ if (rtt_diff < 0) { rtt_diff *= -1; } /* Must be at least 1% reduction */ if (rack->rc_gp_saw_rec && (rack->rc_gp_no_rec_chg == 0)) { /* We have been in recovery ding it too */ if (timely_says == 2) { new_per = rack_decrease_highrtt(rack, rack->r_ctl.rack_per_of_gp_rec, rtt); alt = rack_get_decrease(rack, rack->r_ctl.rack_per_of_gp_rec, rtt_diff); if (alt < new_per) val = alt; else val = new_per; } else val = new_per = alt = rack_get_decrease(rack, rack->r_ctl.rack_per_of_gp_rec, rtt_diff); if (rack->r_ctl.rack_per_of_gp_rec > val) { rec_red = (rack->r_ctl.rack_per_of_gp_rec - val); rack->r_ctl.rack_per_of_gp_rec = (uint16_t)val; } else { rack->r_ctl.rack_per_of_gp_rec = rack_per_lower_bound; rec_red = 0; } if (rack_per_lower_bound > rack->r_ctl.rack_per_of_gp_rec) rack->r_ctl.rack_per_of_gp_rec = rack_per_lower_bound; logged |= 1; } if (rack->rc_gp_saw_ss) { /* Sent in SS */ if (timely_says == 2) { new_per = rack_decrease_highrtt(rack, rack->r_ctl.rack_per_of_gp_ss, rtt); alt = rack_get_decrease(rack, rack->r_ctl.rack_per_of_gp_ss, rtt_diff); if (alt < new_per) val = alt; else val = new_per; } else val = new_per = alt = rack_get_decrease(rack, rack->r_ctl.rack_per_of_gp_ss, rtt_diff); if (rack->r_ctl.rack_per_of_gp_ss > new_per) { ss_red = rack->r_ctl.rack_per_of_gp_ss - val; rack->r_ctl.rack_per_of_gp_ss = (uint16_t)val; } else { ss_red = new_per; rack->r_ctl.rack_per_of_gp_ss = rack_per_lower_bound; logvar = new_per; logvar <<= 32; logvar |= alt; logvar2 = (uint32_t)rtt; logvar2 <<= 32; logvar2 |= (uint32_t)rtt_diff; logvar3 = rack_gp_rtt_maxmul; logvar3 <<= 32; logvar3 |= get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt); rack_log_timely(rack, timely_says, logvar2, logvar3, logvar, __LINE__, 10); } if (rack_per_lower_bound > rack->r_ctl.rack_per_of_gp_ss) rack->r_ctl.rack_per_of_gp_ss = rack_per_lower_bound; logged |= 4; } else if (rack->rc_gp_saw_ca) { /* Sent in CA */ if (timely_says == 2) { new_per = rack_decrease_highrtt(rack, rack->r_ctl.rack_per_of_gp_ca, rtt); alt = rack_get_decrease(rack, rack->r_ctl.rack_per_of_gp_ca, rtt_diff); if (alt < new_per) val = alt; else val = new_per; } else val = new_per = alt = rack_get_decrease(rack, rack->r_ctl.rack_per_of_gp_ca, rtt_diff); if (rack->r_ctl.rack_per_of_gp_ca > val) { ca_red = rack->r_ctl.rack_per_of_gp_ca - val; rack->r_ctl.rack_per_of_gp_ca = (uint16_t)val; } else { rack->r_ctl.rack_per_of_gp_ca = rack_per_lower_bound; ca_red = 0; logvar = new_per; logvar <<= 32; logvar |= alt; logvar2 = (uint32_t)rtt; logvar2 <<= 32; logvar2 |= (uint32_t)rtt_diff; logvar3 = rack_gp_rtt_maxmul; logvar3 <<= 32; logvar3 |= get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt); rack_log_timely(rack, timely_says, logvar2, logvar3, logvar, __LINE__, 10); } if (rack_per_lower_bound > rack->r_ctl.rack_per_of_gp_ca) rack->r_ctl.rack_per_of_gp_ca = rack_per_lower_bound; logged |= 2; } if (rack->rc_gp_timely_dec_cnt < 0x7) { rack->rc_gp_timely_dec_cnt++; if (rack_timely_dec_clear && (rack->rc_gp_timely_dec_cnt == rack_timely_dec_clear)) rack->rc_gp_timely_dec_cnt = 0; } logvar = ss_red; logvar <<= 32; logvar |= ca_red; rack_log_timely(rack, logged, rec_red, rack_per_lower_bound, logvar, __LINE__, 2); } static void rack_log_rtt_shrinks(struct tcp_rack *rack, uint32_t us_cts, uint32_t rtt, uint32_t line, uint8_t reas) { if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.flex1 = line; log.u_bbr.flex2 = rack->r_ctl.rc_time_probertt_starts; log.u_bbr.flex3 = rack->r_ctl.rc_lower_rtt_us_cts; log.u_bbr.flex4 = rack->r_ctl.rack_per_of_gp_ss; log.u_bbr.flex5 = rtt; log.u_bbr.flex6 = rack->rc_highly_buffered; log.u_bbr.flex6 <<= 1; log.u_bbr.flex6 |= rack->forced_ack; log.u_bbr.flex6 <<= 1; log.u_bbr.flex6 |= rack->rc_gp_dyn_mul; log.u_bbr.flex6 <<= 1; log.u_bbr.flex6 |= rack->in_probe_rtt; log.u_bbr.flex6 <<= 1; log.u_bbr.flex6 |= rack->measure_saw_probe_rtt; log.u_bbr.flex7 = rack->r_ctl.rack_per_of_gp_probertt; log.u_bbr.pacing_gain = rack->r_ctl.rack_per_of_gp_ca; log.u_bbr.cwnd_gain = rack->r_ctl.rack_per_of_gp_rec; log.u_bbr.flex8 = reas; log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.delRate = rack_get_bw(rack); log.u_bbr.cur_del_rate = rack->r_ctl.rc_highest_us_rtt; log.u_bbr.cur_del_rate <<= 32; log.u_bbr.cur_del_rate |= rack->r_ctl.rc_lowest_us_rtt; log.u_bbr.applimited = rack->r_ctl.rc_time_probertt_entered; log.u_bbr.pkts_out = rack->r_ctl.rc_rtt_diff; log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); log.u_bbr.epoch = rack->r_ctl.rc_gp_srtt; log.u_bbr.lt_epoch = rack->r_ctl.rc_prev_gp_srtt; log.u_bbr.pkt_epoch = rack->r_ctl.rc_lower_rtt_us_cts; log.u_bbr.delivered = rack->r_ctl.rc_target_probertt_flight; log.u_bbr.lost = get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt); log.u_bbr.rttProp = us_cts; log.u_bbr.rttProp <<= 32; log.u_bbr.rttProp |= rack->r_ctl.rc_entry_gp_rtt; TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, BBR_LOG_RTT_SHRINKS, 0, 0, &log, false, &rack->r_ctl.act_rcv_time); } } static void rack_set_prtt_target(struct tcp_rack *rack, uint32_t segsiz, uint32_t rtt) { uint64_t bwdp; bwdp = rack_get_bw(rack); bwdp *= (uint64_t)rtt; bwdp /= (uint64_t)HPTS_USEC_IN_SEC; rack->r_ctl.rc_target_probertt_flight = roundup((uint32_t)bwdp, segsiz); if (rack->r_ctl.rc_target_probertt_flight < (segsiz * rack_timely_min_segs)) { /* * A window protocol must be able to have 4 packets * outstanding as the floor in order to function * (especially considering delayed ack :D). */ rack->r_ctl.rc_target_probertt_flight = (segsiz * rack_timely_min_segs); } } static void rack_enter_probertt(struct tcp_rack *rack, uint32_t us_cts) { /** * ProbeRTT is a bit different in rack_pacing than in * BBR. It is like BBR in that it uses the lowering of * the RTT as a signal that we saw something new and * counts from there for how long between. But it is * different in that its quite simple. It does not * play with the cwnd and wait until we get down * to N segments outstanding and hold that for * 200ms. Instead it just sets the pacing reduction * rate to a set percentage (70 by default) and hold * that for a number of recent GP Srtt's. */ uint32_t segsiz; if (rack->rc_gp_dyn_mul == 0) return; if (rack->rc_tp->snd_max == rack->rc_tp->snd_una) { /* We are idle */ return; } if ((rack->rc_tp->t_flags & TF_GPUTINPROG) && SEQ_GT(rack->rc_tp->snd_una, rack->rc_tp->gput_seq)) { /* * Stop the goodput now, the idea here is * that future measurements with in_probe_rtt * won't register if they are not greater so * we want to get what info (if any) is available * now. */ rack_do_goodput_measurement(rack->rc_tp, rack, rack->rc_tp->snd_una, __LINE__, RACK_QUALITY_PROBERTT); } rack->r_ctl.rack_per_of_gp_probertt = rack_per_of_gp_probertt; rack->r_ctl.rc_time_probertt_entered = us_cts; segsiz = min(ctf_fixed_maxseg(rack->rc_tp), rack->r_ctl.rc_pace_min_segs); rack->in_probe_rtt = 1; rack->measure_saw_probe_rtt = 1; rack->r_ctl.rc_lower_rtt_us_cts = us_cts; rack->r_ctl.rc_time_probertt_starts = 0; rack->r_ctl.rc_entry_gp_rtt = rack->r_ctl.rc_gp_srtt; if (rack_probertt_use_min_rtt_entry) rack_set_prtt_target(rack, segsiz, get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt)); else rack_set_prtt_target(rack, segsiz, rack->r_ctl.rc_gp_srtt); rack_log_rtt_shrinks(rack, us_cts, get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt), __LINE__, RACK_RTTS_ENTERPROBE); } static void rack_exit_probertt(struct tcp_rack *rack, uint32_t us_cts) { struct rack_sendmap *rsm; uint32_t segsiz; segsiz = min(ctf_fixed_maxseg(rack->rc_tp), rack->r_ctl.rc_pace_min_segs); rack->in_probe_rtt = 0; if ((rack->rc_tp->t_flags & TF_GPUTINPROG) && SEQ_GT(rack->rc_tp->snd_una, rack->rc_tp->gput_seq)) { /* * Stop the goodput now, the idea here is * that future measurements with in_probe_rtt * won't register if they are not greater so * we want to get what info (if any) is available * now. */ rack_do_goodput_measurement(rack->rc_tp, rack, rack->rc_tp->snd_una, __LINE__, RACK_QUALITY_PROBERTT); } else if (rack->rc_tp->t_flags & TF_GPUTINPROG) { /* * We don't have enough data to make a measurement. * So lets just stop and start here after exiting * probe-rtt. We probably are not interested in * the results anyway. */ rack->rc_tp->t_flags &= ~TF_GPUTINPROG; } /* * Measurements through the current snd_max are going * to be limited by the slower pacing rate. * * We need to mark these as app-limited so we * don't collapse the b/w. */ rsm = tqhash_max(rack->r_ctl.tqh); if (rsm && ((rsm->r_flags & RACK_APP_LIMITED) == 0)) { if (rack->r_ctl.rc_app_limited_cnt == 0) rack->r_ctl.rc_end_appl = rack->r_ctl.rc_first_appl = rsm; else { /* * Go out to the end app limited and mark * this new one as next and move the end_appl up * to this guy. */ if (rack->r_ctl.rc_end_appl) rack->r_ctl.rc_end_appl->r_nseq_appl = rsm->r_start; rack->r_ctl.rc_end_appl = rsm; } rsm->r_flags |= RACK_APP_LIMITED; rack->r_ctl.rc_app_limited_cnt++; } /* * Now, we need to examine our pacing rate multipliers. * If its under 100%, we need to kick it back up to * 100%. We also don't let it be over our "max" above * the actual rate i.e. 100% + rack_clamp_atexit_prtt. * Note setting clamp_atexit_prtt to 0 has the effect * of setting CA/SS to 100% always at exit (which is * the default behavior). */ if (rack_probertt_clear_is) { rack->rc_gp_incr = 0; rack->rc_gp_bwred = 0; rack->rc_gp_timely_inc_cnt = 0; rack->rc_gp_timely_dec_cnt = 0; } /* Do we do any clamping at exit? */ if (rack->rc_highly_buffered && rack_atexit_prtt_hbp) { rack->r_ctl.rack_per_of_gp_ca = rack_atexit_prtt_hbp; rack->r_ctl.rack_per_of_gp_ss = rack_atexit_prtt_hbp; } if ((rack->rc_highly_buffered == 0) && rack_atexit_prtt) { rack->r_ctl.rack_per_of_gp_ca = rack_atexit_prtt; rack->r_ctl.rack_per_of_gp_ss = rack_atexit_prtt; } /* * Lets set rtt_diff to 0, so that we will get a "boost" * after exiting. */ rack->r_ctl.rc_rtt_diff = 0; /* Clear all flags so we start fresh */ rack->rc_tp->t_bytes_acked = 0; rack->rc_tp->t_ccv.flags &= ~CCF_ABC_SENTAWND; /* * If configured to, set the cwnd and ssthresh to * our targets. */ if (rack_probe_rtt_sets_cwnd) { uint64_t ebdp; uint32_t setto; /* Set ssthresh so we get into CA once we hit our target */ if (rack_probertt_use_min_rtt_exit == 1) { /* Set to min rtt */ rack_set_prtt_target(rack, segsiz, get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt)); } else if (rack_probertt_use_min_rtt_exit == 2) { /* Set to current gp rtt */ rack_set_prtt_target(rack, segsiz, rack->r_ctl.rc_gp_srtt); } else if (rack_probertt_use_min_rtt_exit == 3) { /* Set to entry gp rtt */ rack_set_prtt_target(rack, segsiz, rack->r_ctl.rc_entry_gp_rtt); } else { uint64_t sum; uint32_t setval; sum = rack->r_ctl.rc_entry_gp_rtt; sum *= 10; sum /= (uint64_t)(max(1, rack->r_ctl.rc_gp_srtt)); if (sum >= 20) { /* * A highly buffered path needs * cwnd space for timely to work. * Lets set things up as if * we are heading back here again. */ setval = rack->r_ctl.rc_entry_gp_rtt; } else if (sum >= 15) { /* * Lets take the smaller of the * two since we are just somewhat * buffered. */ setval = rack->r_ctl.rc_gp_srtt; if (setval > rack->r_ctl.rc_entry_gp_rtt) setval = rack->r_ctl.rc_entry_gp_rtt; } else { /* * Here we are not highly buffered * and should pick the min we can to * keep from causing loss. */ setval = get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt); } rack_set_prtt_target(rack, segsiz, setval); } if (rack_probe_rtt_sets_cwnd > 1) { /* There is a percentage here to boost */ ebdp = rack->r_ctl.rc_target_probertt_flight; ebdp *= rack_probe_rtt_sets_cwnd; ebdp /= 100; setto = rack->r_ctl.rc_target_probertt_flight + ebdp; } else setto = rack->r_ctl.rc_target_probertt_flight; rack->rc_tp->snd_cwnd = roundup(setto, segsiz); if (rack->rc_tp->snd_cwnd < (segsiz * rack_timely_min_segs)) { /* Enforce a min */ rack->rc_tp->snd_cwnd = segsiz * rack_timely_min_segs; } /* If we set in the cwnd also set the ssthresh point so we are in CA */ rack->rc_tp->snd_ssthresh = (rack->rc_tp->snd_cwnd - 1); } rack_log_rtt_shrinks(rack, us_cts, get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt), __LINE__, RACK_RTTS_EXITPROBE); /* Clear times last so log has all the info */ rack->r_ctl.rc_probertt_sndmax_atexit = rack->rc_tp->snd_max; rack->r_ctl.rc_time_probertt_entered = us_cts; rack->r_ctl.rc_time_probertt_starts = rack->r_ctl.rc_lower_rtt_us_cts = us_cts; rack->r_ctl.rc_time_of_last_probertt = us_cts; } static void rack_check_probe_rtt(struct tcp_rack *rack, uint32_t us_cts) { /* Check in on probe-rtt */ if (rack->rc_gp_filled == 0) { /* We do not do p-rtt unless we have gp measurements */ return; } if (rack->in_probe_rtt) { uint64_t no_overflow; uint32_t endtime, must_stay; if (rack->r_ctl.rc_went_idle_time && ((us_cts - rack->r_ctl.rc_went_idle_time) > rack_min_probertt_hold)) { /* * We went idle during prtt, just exit now. */ rack_exit_probertt(rack, us_cts); } else if (rack_probe_rtt_safety_val && TSTMP_GT(us_cts, rack->r_ctl.rc_time_probertt_entered) && ((us_cts - rack->r_ctl.rc_time_probertt_entered) > rack_probe_rtt_safety_val)) { /* * Probe RTT safety value triggered! */ rack_log_rtt_shrinks(rack, us_cts, get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt), __LINE__, RACK_RTTS_SAFETY); rack_exit_probertt(rack, us_cts); } /* Calculate the max we will wait */ endtime = rack->r_ctl.rc_time_probertt_entered + (rack->r_ctl.rc_gp_srtt * rack_max_drain_wait); if (rack->rc_highly_buffered) endtime += (rack->r_ctl.rc_gp_srtt * rack_max_drain_hbp); /* Calculate the min we must wait */ must_stay = rack->r_ctl.rc_time_probertt_entered + (rack->r_ctl.rc_gp_srtt * rack_must_drain); if ((ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked) > rack->r_ctl.rc_target_probertt_flight) && TSTMP_LT(us_cts, endtime)) { uint32_t calc; /* Do we lower more? */ no_exit: if (TSTMP_GT(us_cts, rack->r_ctl.rc_time_probertt_entered)) calc = us_cts - rack->r_ctl.rc_time_probertt_entered; else calc = 0; calc /= max(rack->r_ctl.rc_gp_srtt, 1); if (calc) { /* Maybe */ calc *= rack_per_of_gp_probertt_reduce; rack->r_ctl.rack_per_of_gp_probertt = rack_per_of_gp_probertt - calc; /* Limit it too */ if (rack->r_ctl.rack_per_of_gp_probertt < rack_per_of_gp_lowthresh) rack->r_ctl.rack_per_of_gp_probertt = rack_per_of_gp_lowthresh; } /* We must reach target or the time set */ return; } if (rack->r_ctl.rc_time_probertt_starts == 0) { if ((TSTMP_LT(us_cts, must_stay) && rack->rc_highly_buffered) || (ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked) > rack->r_ctl.rc_target_probertt_flight)) { /* We are not past the must_stay time */ goto no_exit; } rack_log_rtt_shrinks(rack, us_cts, get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt), __LINE__, RACK_RTTS_REACHTARGET); rack->r_ctl.rc_time_probertt_starts = us_cts; if (rack->r_ctl.rc_time_probertt_starts == 0) rack->r_ctl.rc_time_probertt_starts = 1; /* Restore back to our rate we want to pace at in prtt */ rack->r_ctl.rack_per_of_gp_probertt = rack_per_of_gp_probertt; } /* * Setup our end time, some number of gp_srtts plus 200ms. */ no_overflow = ((uint64_t)rack->r_ctl.rc_gp_srtt * (uint64_t)rack_probertt_gpsrtt_cnt_mul); if (rack_probertt_gpsrtt_cnt_div) endtime = (uint32_t)(no_overflow / (uint64_t)rack_probertt_gpsrtt_cnt_div); else endtime = 0; endtime += rack_min_probertt_hold; endtime += rack->r_ctl.rc_time_probertt_starts; if (TSTMP_GEQ(us_cts, endtime)) { /* yes, exit probertt */ rack_exit_probertt(rack, us_cts); } } else if ((us_cts - rack->r_ctl.rc_lower_rtt_us_cts) >= rack_time_between_probertt) { /* Go into probertt, its been too long since we went lower */ rack_enter_probertt(rack, us_cts); } } static void rack_update_multiplier(struct tcp_rack *rack, int32_t timely_says, uint64_t last_bw_est, uint32_t rtt, int32_t rtt_diff) { uint64_t cur_bw, up_bnd, low_bnd, subfr; uint32_t losses; if ((rack->rc_gp_dyn_mul == 0) || (rack->use_fixed_rate) || (rack->in_probe_rtt) || (rack->rc_always_pace == 0)) { /* No dynamic GP multiplier in play */ return; } losses = rack->r_ctl.rc_loss_count - rack->r_ctl.rc_loss_at_start; cur_bw = rack_get_bw(rack); /* Calculate our up and down range */ up_bnd = rack->r_ctl.last_gp_comp_bw * (uint64_t)rack_gp_per_bw_mul_up; up_bnd /= 100; up_bnd += rack->r_ctl.last_gp_comp_bw; subfr = (uint64_t)rack->r_ctl.last_gp_comp_bw * (uint64_t)rack_gp_per_bw_mul_down; subfr /= 100; low_bnd = rack->r_ctl.last_gp_comp_bw - subfr; if ((timely_says == 2) && (rack->r_ctl.rc_no_push_at_mrtt)) { /* * This is the case where our RTT is above * the max target and we have been configured * to just do timely no bonus up stuff in that case. * * There are two configurations, set to 1, and we * just do timely if we are over our max. If its * set above 1 then we slam the multipliers down * to 100 and then decrement per timely. */ rack_log_timely(rack, timely_says, cur_bw, low_bnd, up_bnd, __LINE__, 3); if (rack->r_ctl.rc_no_push_at_mrtt > 1) rack_validate_multipliers_at_or_below_100(rack); rack_decrease_bw_mul(rack, timely_says, rtt, rtt_diff); } else if ((timely_says != 0) && (last_bw_est < low_bnd) && !losses) { /* * We are decreasing this is a bit complicated this * means we are loosing ground. This could be * because another flow entered and we are competing * for b/w with it. This will push the RTT up which * makes timely unusable unless we want to get shoved * into a corner and just be backed off (the age * old problem with delay based CC). * * On the other hand if it was a route change we * would like to stay somewhat contained and not * blow out the buffers. */ rack_log_timely(rack, timely_says, cur_bw, low_bnd, up_bnd, __LINE__, 3); rack->r_ctl.last_gp_comp_bw = cur_bw; if (rack->rc_gp_bwred == 0) { /* Go into reduction counting */ rack->rc_gp_bwred = 1; rack->rc_gp_timely_dec_cnt = 0; } if (rack->rc_gp_timely_dec_cnt < rack_timely_max_push_drop) { /* * Push another time with a faster pacing * to try to gain back (we include override to * get a full raise factor). */ if ((rack->rc_gp_saw_ca && rack->r_ctl.rack_per_of_gp_ca <= rack_down_raise_thresh) || (rack->rc_gp_saw_ss && rack->r_ctl.rack_per_of_gp_ss <= rack_down_raise_thresh) || (timely_says == 0) || (rack_down_raise_thresh == 0)) { /* * Do an override up in b/w if we were * below the threshold or if the threshold * is zero we always do the raise. */ rack_increase_bw_mul(rack, timely_says, cur_bw, last_bw_est, 1); } else { /* Log it stays the same */ rack_log_timely(rack, 0, last_bw_est, low_bnd, 0, __LINE__, 11); } rack->rc_gp_timely_dec_cnt++; /* We are not incrementing really no-count */ rack->rc_gp_incr = 0; rack->rc_gp_timely_inc_cnt = 0; } else { /* * Lets just use the RTT * information and give up * pushing. */ goto use_timely; } } else if ((timely_says != 2) && !losses && (last_bw_est > up_bnd)) { /* * We are increasing b/w lets keep going, updating * our b/w and ignoring any timely input, unless * of course we are at our max raise (if there is one). */ rack_log_timely(rack, timely_says, cur_bw, low_bnd, up_bnd, __LINE__, 3); rack->r_ctl.last_gp_comp_bw = cur_bw; if (rack->rc_gp_saw_ss && rack->r_ctl.rack_per_upper_bound_ss && (rack->r_ctl.rack_per_of_gp_ss == rack->r_ctl.rack_per_upper_bound_ss)) { /* * In cases where we can't go higher * we should just use timely. */ goto use_timely; } if (rack->rc_gp_saw_ca && rack->r_ctl.rack_per_upper_bound_ca && (rack->r_ctl.rack_per_of_gp_ca == rack->r_ctl.rack_per_upper_bound_ca)) { /* * In cases where we can't go higher * we should just use timely. */ goto use_timely; } rack->rc_gp_bwred = 0; rack->rc_gp_timely_dec_cnt = 0; /* You get a set number of pushes if timely is trying to reduce */ if ((rack->rc_gp_incr < rack_timely_max_push_rise) || (timely_says == 0)) { rack_increase_bw_mul(rack, timely_says, cur_bw, last_bw_est, 0); } else { /* Log it stays the same */ rack_log_timely(rack, 0, last_bw_est, up_bnd, 0, __LINE__, 12); } return; } else { /* * We are staying between the lower and upper range bounds * so use timely to decide. */ rack_log_timely(rack, timely_says, cur_bw, low_bnd, up_bnd, __LINE__, 3); use_timely: if (timely_says) { rack->rc_gp_incr = 0; rack->rc_gp_timely_inc_cnt = 0; if ((rack->rc_gp_timely_dec_cnt < rack_timely_max_push_drop) && !losses && (last_bw_est < low_bnd)) { /* We are loosing ground */ rack_increase_bw_mul(rack, timely_says, cur_bw, last_bw_est, 0); rack->rc_gp_timely_dec_cnt++; /* We are not incrementing really no-count */ rack->rc_gp_incr = 0; rack->rc_gp_timely_inc_cnt = 0; } else rack_decrease_bw_mul(rack, timely_says, rtt, rtt_diff); } else { rack->rc_gp_bwred = 0; rack->rc_gp_timely_dec_cnt = 0; rack_increase_bw_mul(rack, timely_says, cur_bw, last_bw_est, 0); } } } static int32_t rack_make_timely_judgement(struct tcp_rack *rack, uint32_t rtt, int32_t rtt_diff, uint32_t prev_rtt) { int32_t timely_says; uint64_t log_mult, log_rtt_a_diff; log_rtt_a_diff = rtt; log_rtt_a_diff <<= 32; log_rtt_a_diff |= (uint32_t)rtt_diff; if (rtt >= (get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt) * rack_gp_rtt_maxmul)) { /* Reduce the b/w multiplier */ timely_says = 2; log_mult = get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt) * rack_gp_rtt_maxmul; log_mult <<= 32; log_mult |= prev_rtt; rack_log_timely(rack, timely_says, log_mult, get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt), log_rtt_a_diff, __LINE__, 4); } else if (rtt <= (get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt) + ((get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt) * rack_gp_rtt_minmul) / max(rack_gp_rtt_mindiv , 1)))) { /* Increase the b/w multiplier */ log_mult = get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt) + ((get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt) * rack_gp_rtt_minmul) / max(rack_gp_rtt_mindiv , 1)); log_mult <<= 32; log_mult |= prev_rtt; timely_says = 0; rack_log_timely(rack, timely_says, log_mult , get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt), log_rtt_a_diff, __LINE__, 5); } else { /* * Use a gradient to find it the timely gradient * is: * grad = rc_rtt_diff / min_rtt; * * anything below or equal to 0 will be * a increase indication. Anything above * zero is a decrease. Note we take care * of the actual gradient calculation * in the reduction (its not needed for * increase). */ log_mult = prev_rtt; if (rtt_diff <= 0) { /* * Rttdiff is less than zero, increase the * b/w multiplier (its 0 or negative) */ timely_says = 0; rack_log_timely(rack, timely_says, log_mult, get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt), log_rtt_a_diff, __LINE__, 6); } else { /* Reduce the b/w multiplier */ timely_says = 1; rack_log_timely(rack, timely_says, log_mult, get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt), log_rtt_a_diff, __LINE__, 7); } } return (timely_says); } static __inline int rack_in_gp_window(struct tcpcb *tp, struct rack_sendmap *rsm) { if (SEQ_GEQ(rsm->r_start, tp->gput_seq) && SEQ_LEQ(rsm->r_end, tp->gput_ack)) { /** * This covers the case that the * resent is completely inside * the gp range or up to it. * |----------------| * |-----| * |----| * |---| */ return (1); } else if (SEQ_LT(rsm->r_start, tp->gput_seq) && SEQ_GT(rsm->r_end, tp->gput_seq)){ /** * This covers the case of * |--------------| * |-------->| */ return (1); } else if (SEQ_GEQ(rsm->r_start, tp->gput_seq) && SEQ_LT(rsm->r_start, tp->gput_ack) && SEQ_GEQ(rsm->r_end, tp->gput_ack)) { /** * This covers the case of * |--------------| * |-------->| */ return (1); } return (0); } static __inline void rack_mark_in_gp_win(struct tcpcb *tp, struct rack_sendmap *rsm) { if ((tp->t_flags & TF_GPUTINPROG) == 0) return; /* * We have a Goodput measurement in progress. Mark * the send if its within the window. If its not * in the window make sure it does not have the mark. */ if (rack_in_gp_window(tp, rsm)) rsm->r_flags |= RACK_IN_GP_WIN; else rsm->r_flags &= ~RACK_IN_GP_WIN; } static __inline void rack_clear_gp_marks(struct tcpcb *tp, struct tcp_rack *rack) { /* A GP measurement is ending, clear all marks on the send map*/ struct rack_sendmap *rsm = NULL; rsm = tqhash_find(rack->r_ctl.tqh, tp->gput_seq); if (rsm == NULL) { rsm = tqhash_min(rack->r_ctl.tqh); } /* Nothing left? */ while ((rsm != NULL) && (SEQ_GEQ(tp->gput_ack, rsm->r_start))){ rsm->r_flags &= ~RACK_IN_GP_WIN; rsm = tqhash_next(rack->r_ctl.tqh, rsm); } } static __inline void rack_tend_gp_marks(struct tcpcb *tp, struct tcp_rack *rack) { struct rack_sendmap *rsm = NULL; if (tp->snd_una == tp->snd_max) { /* Nothing outstanding yet, nothing to do here */ return; } if (SEQ_GT(tp->gput_seq, tp->snd_una)) { /* * We are measuring ahead of some outstanding * data. We need to walk through up until we get * to gp_seq marking so that no rsm is set incorrectly * with RACK_IN_GP_WIN. */ rsm = tqhash_min(rack->r_ctl.tqh); while (rsm != NULL) { rack_mark_in_gp_win(tp, rsm); if (SEQ_GEQ(rsm->r_end, tp->gput_seq)) break; rsm = tqhash_next(rack->r_ctl.tqh, rsm); } } if (rsm == NULL) { /* * Need to find the GP seq, if rsm is * set we stopped as we hit it. */ rsm = tqhash_find(rack->r_ctl.tqh, tp->gput_seq); if (rsm == NULL) return; rack_mark_in_gp_win(tp, rsm); } /* * Now we may need to mark already sent rsm, ahead of * gput_seq in the window since they may have been sent * *before* we started our measurment. The rsm, if non-null * has been marked (note if rsm would have been NULL we would have * returned in the previous block). So we go to the next, and continue * until we run out of entries or we exceed the gp_ack value. */ rsm = tqhash_next(rack->r_ctl.tqh, rsm); while (rsm) { rack_mark_in_gp_win(tp, rsm); if (SEQ_GT(rsm->r_end, tp->gput_ack)) break; rsm = tqhash_next(rack->r_ctl.tqh, rsm); } } static void rack_do_goodput_measurement(struct tcpcb *tp, struct tcp_rack *rack, tcp_seq th_ack, int line, uint8_t quality) { uint64_t tim, bytes_ps, stim, utim; uint32_t segsiz, bytes, reqbytes, us_cts; int32_t gput, new_rtt_diff, timely_says; uint64_t resid_bw, subpart = 0, addpart = 0, srtt; int did_add = 0; us_cts = tcp_tv_to_usectick(&rack->r_ctl.act_rcv_time); segsiz = min(ctf_fixed_maxseg(tp), rack->r_ctl.rc_pace_min_segs); if (TSTMP_GEQ(us_cts, tp->gput_ts)) tim = us_cts - tp->gput_ts; else tim = 0; if (rack->r_ctl.rc_gp_cumack_ts > rack->r_ctl.rc_gp_output_ts) stim = rack->r_ctl.rc_gp_cumack_ts - rack->r_ctl.rc_gp_output_ts; else stim = 0; /* * Use the larger of the send time or ack time. This prevents us * from being influenced by ack artifacts to come up with too * high of measurement. Note that since we are spanning over many more * bytes in most of our measurements hopefully that is less likely to * occur. */ if (tim > stim) utim = max(tim, 1); else utim = max(stim, 1); reqbytes = min(rc_init_window(rack), (MIN_GP_WIN * segsiz)); rack_log_gpset(rack, th_ack, us_cts, rack->r_ctl.rc_gp_cumack_ts, __LINE__, 3, NULL); if ((tim == 0) && (stim == 0)) { /* * Invalid measurement time, maybe * all on one ack/one send? */ bytes = 0; bytes_ps = 0; rack_log_pacing_delay_calc(rack, bytes_ps, reqbytes, 0, 0, 0, 10, __LINE__, NULL, quality); goto skip_measurement; } if (rack->r_ctl.rc_gp_lowrtt == 0xffffffff) { /* We never made a us_rtt measurement? */ bytes = 0; bytes_ps = 0; rack_log_pacing_delay_calc(rack, bytes_ps, reqbytes, 0, 0, 0, 10, __LINE__, NULL, quality); goto skip_measurement; } /* * Calculate the maximum possible b/w this connection * could have. We base our calculation on the lowest * rtt we have seen during the measurement and the * largest rwnd the client has given us in that time. This * forms a BDP that is the maximum that we could ever * get to the client. Anything larger is not valid. * * I originally had code here that rejected measurements * where the time was less than 1/2 the latest us_rtt. * But after thinking on that I realized its wrong since * say you had a 150Mbps or even 1Gbps link, and you * were a long way away.. example I am in Europe (100ms rtt) * talking to my 1Gbps link in S.C. Now measuring say 150,000 * bytes my time would be 1.2ms, and yet my rtt would say * the measurement was invalid the time was < 50ms. The * same thing is true for 150Mb (8ms of time). * * A better way I realized is to look at what the maximum * the connection could possibly do. This is gated on * the lowest RTT we have seen and the highest rwnd. * We should in theory never exceed that, if we are * then something on the path is storing up packets * and then feeding them all at once to our endpoint * messing up our measurement. */ rack->r_ctl.last_max_bw = rack->r_ctl.rc_gp_high_rwnd; rack->r_ctl.last_max_bw *= HPTS_USEC_IN_SEC; rack->r_ctl.last_max_bw /= rack->r_ctl.rc_gp_lowrtt; if (SEQ_LT(th_ack, tp->gput_seq)) { /* No measurement can be made */ bytes = 0; bytes_ps = 0; rack_log_pacing_delay_calc(rack, bytes_ps, reqbytes, 0, 0, 0, 10, __LINE__, NULL, quality); goto skip_measurement; } else bytes = (th_ack - tp->gput_seq); bytes_ps = (uint64_t)bytes; /* * Don't measure a b/w for pacing unless we have gotten at least * an initial windows worth of data in this measurement interval. * * Small numbers of bytes get badly influenced by delayed ack and * other artifacts. Note we take the initial window or our * defined minimum GP (defaulting to 10 which hopefully is the * IW). */ if (rack->rc_gp_filled == 0) { /* * The initial estimate is special. We * have blasted out an IW worth of packets * without a real valid ack ts results. We * then setup the app_limited_needs_set flag, * this should get the first ack in (probably 2 * MSS worth) to be recorded as the timestamp. * We thus allow a smaller number of bytes i.e. * IW - 2MSS. */ reqbytes -= (2 * segsiz); /* Also lets fill previous for our first measurement to be neutral */ rack->r_ctl.rc_prev_gp_srtt = rack->r_ctl.rc_gp_srtt; } if ((bytes_ps < reqbytes) || rack->app_limited_needs_set) { rack_log_pacing_delay_calc(rack, bytes_ps, reqbytes, rack->r_ctl.rc_app_limited_cnt, 0, 0, 10, __LINE__, NULL, quality); goto skip_measurement; } /* * We now need to calculate the Timely like status so * we can update (possibly) the b/w multipliers. */ new_rtt_diff = (int32_t)rack->r_ctl.rc_gp_srtt - (int32_t)rack->r_ctl.rc_prev_gp_srtt; if (rack->rc_gp_filled == 0) { /* No previous reading */ rack->r_ctl.rc_rtt_diff = new_rtt_diff; } else { if (rack->measure_saw_probe_rtt == 0) { /* * We don't want a probertt to be counted * since it will be negative incorrectly. We * expect to be reducing the RTT when we * pace at a slower rate. */ rack->r_ctl.rc_rtt_diff -= (rack->r_ctl.rc_rtt_diff / 8); rack->r_ctl.rc_rtt_diff += (new_rtt_diff / 8); } } timely_says = rack_make_timely_judgement(rack, rack->r_ctl.rc_gp_srtt, rack->r_ctl.rc_rtt_diff, rack->r_ctl.rc_prev_gp_srtt ); bytes_ps *= HPTS_USEC_IN_SEC; bytes_ps /= utim; if (bytes_ps > rack->r_ctl.last_max_bw) { /* * Something is on path playing * since this b/w is not possible based * on our BDP (highest rwnd and lowest rtt * we saw in the measurement window). * * Another option here would be to * instead skip the measurement. */ rack_log_pacing_delay_calc(rack, bytes, reqbytes, bytes_ps, rack->r_ctl.last_max_bw, 0, 11, __LINE__, NULL, quality); bytes_ps = rack->r_ctl.last_max_bw; } /* We store gp for b/w in bytes per second */ if (rack->rc_gp_filled == 0) { /* Initial measurement */ if (bytes_ps) { rack->r_ctl.gp_bw = bytes_ps; rack->rc_gp_filled = 1; rack->r_ctl.num_measurements = 1; rack_set_pace_segments(rack->rc_tp, rack, __LINE__, NULL); } else { rack_log_pacing_delay_calc(rack, bytes_ps, reqbytes, rack->r_ctl.rc_app_limited_cnt, 0, 0, 10, __LINE__, NULL, quality); } if (tcp_in_hpts(rack->rc_tp) && (rack->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT)) { /* * Ok we can't trust the pacer in this case * where we transition from un-paced to paced. * Or for that matter when the burst mitigation * was making a wild guess and got it wrong. * Stop the pacer and clear up all the aggregate * delays etc. */ tcp_hpts_remove(rack->rc_tp); rack->r_ctl.rc_hpts_flags = 0; rack->r_ctl.rc_last_output_to = 0; } did_add = 2; } else if (rack->r_ctl.num_measurements < RACK_REQ_AVG) { /* Still a small number run an average */ rack->r_ctl.gp_bw += bytes_ps; addpart = rack->r_ctl.num_measurements; rack->r_ctl.num_measurements++; if (rack->r_ctl.num_measurements >= RACK_REQ_AVG) { /* We have collected enough to move forward */ rack->r_ctl.gp_bw /= (uint64_t)rack->r_ctl.num_measurements; } rack_set_pace_segments(tp, rack, __LINE__, NULL); did_add = 3; } else { /* * We want to take 1/wma of the goodput and add in to 7/8th * of the old value weighted by the srtt. So if your measurement * period is say 2 SRTT's long you would get 1/4 as the * value, if it was like 1/2 SRTT then you would get 1/16th. * * But we must be careful not to take too much i.e. if the * srtt is say 20ms and the measurement is taken over * 400ms our weight would be 400/20 i.e. 20. On the * other hand if we get a measurement over 1ms with a * 10ms rtt we only want to take a much smaller portion. */ if (rack->r_ctl.num_measurements < 0xff) { rack->r_ctl.num_measurements++; } srtt = (uint64_t)tp->t_srtt; if (srtt == 0) { /* * Strange why did t_srtt go back to zero? */ if (rack->r_ctl.rc_rack_min_rtt) srtt = rack->r_ctl.rc_rack_min_rtt; else srtt = HPTS_USEC_IN_MSEC; } /* * XXXrrs: Note for reviewers, in playing with * dynamic pacing I discovered this GP calculation * as done originally leads to some undesired results. * Basically you can get longer measurements contributing * too much to the WMA. Thus I changed it if you are doing * dynamic adjustments to only do the aportioned adjustment * if we have a very small (time wise) measurement. Longer * measurements just get there weight (defaulting to 1/8) * add to the WMA. We may want to think about changing * this to always do that for both sides i.e. dynamic * and non-dynamic... but considering lots of folks * were playing with this I did not want to change the * calculation per.se. without your thoughts.. Lawerence? * Peter?? */ if (rack->rc_gp_dyn_mul == 0) { subpart = rack->r_ctl.gp_bw * utim; subpart /= (srtt * 8); if (subpart < (rack->r_ctl.gp_bw / 2)) { /* * The b/w update takes no more * away then 1/2 our running total * so factor it in. */ addpart = bytes_ps * utim; addpart /= (srtt * 8); } else { /* * Don't allow a single measurement * to account for more than 1/2 of the * WMA. This could happen on a retransmission * where utim becomes huge compared to * srtt (multiple retransmissions when using * the sending rate which factors in all the * transmissions from the first one). */ subpart = rack->r_ctl.gp_bw / 2; addpart = bytes_ps / 2; } resid_bw = rack->r_ctl.gp_bw - subpart; rack->r_ctl.gp_bw = resid_bw + addpart; did_add = 1; } else { if ((utim / srtt) <= 1) { /* * The b/w update was over a small period * of time. The idea here is to prevent a small * measurement time period from counting * too much. So we scale it based on the * time so it attributes less than 1/rack_wma_divisor * of its measurement. */ subpart = rack->r_ctl.gp_bw * utim; subpart /= (srtt * rack_wma_divisor); addpart = bytes_ps * utim; addpart /= (srtt * rack_wma_divisor); } else { /* * The scaled measurement was long * enough so lets just add in the * portion of the measurement i.e. 1/rack_wma_divisor */ subpart = rack->r_ctl.gp_bw / rack_wma_divisor; addpart = bytes_ps / rack_wma_divisor; } if ((rack->measure_saw_probe_rtt == 0) || (bytes_ps > rack->r_ctl.gp_bw)) { /* * For probe-rtt we only add it in * if its larger, all others we just * add in. */ did_add = 1; resid_bw = rack->r_ctl.gp_bw - subpart; rack->r_ctl.gp_bw = resid_bw + addpart; } } rack_set_pace_segments(tp, rack, __LINE__, NULL); } if ((rack->gp_ready == 0) && (rack->r_ctl.num_measurements >= rack->r_ctl.req_measurements)) { /* We have enough measurements now */ rack->gp_ready = 1; if (rack->dgp_on || rack->rack_hibeta) rack_set_cc_pacing(rack); if (rack->defer_options) rack_apply_deferred_options(rack); } rack_log_pacing_delay_calc(rack, subpart, addpart, bytes_ps, stim, rack_get_bw(rack), 22, did_add, NULL, quality); /* We do not update any multipliers if we are in or have seen a probe-rtt */ if ((rack->measure_saw_probe_rtt == 0) && rack->rc_gp_rtt_set) rack_update_multiplier(rack, timely_says, bytes_ps, rack->r_ctl.rc_gp_srtt, rack->r_ctl.rc_rtt_diff); rack_log_pacing_delay_calc(rack, bytes, tim, bytes_ps, stim, rack_get_bw(rack), 3, line, NULL, quality); rack_log_pacing_delay_calc(rack, bytes, /* flex2 */ tim, /* flex1 */ bytes_ps, /* bw_inuse */ rack->r_ctl.gp_bw, /* delRate */ rack_get_lt_bw(rack), /* rttProp */ 20, line, NULL, 0); /* reset the gp srtt and setup the new prev */ rack->r_ctl.rc_prev_gp_srtt = rack->r_ctl.rc_gp_srtt; /* Record the lost count for the next measurement */ rack->r_ctl.rc_loss_at_start = rack->r_ctl.rc_loss_count; skip_measurement: /* * We restart our diffs based on the gpsrtt in the * measurement window. */ rack->rc_gp_rtt_set = 0; rack->rc_gp_saw_rec = 0; rack->rc_gp_saw_ca = 0; rack->rc_gp_saw_ss = 0; rack->rc_dragged_bottom = 0; if (quality == RACK_QUALITY_HIGH) { /* * Gput in the stats world is in kbps where bytes_ps is * bytes per second so we do ((x * 8)/ 1000). */ gput = (int32_t)((bytes_ps << 3) / (uint64_t)1000); #ifdef STATS stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_GPUT, gput); /* * XXXLAS: This is a temporary hack, and should be * chained off VOI_TCP_GPUT when stats(9) grows an * API to deal with chained VOIs. */ if (tp->t_stats_gput_prev > 0) stats_voi_update_abs_s32(tp->t_stats, VOI_TCP_GPUT_ND, ((gput - tp->t_stats_gput_prev) * 100) / tp->t_stats_gput_prev); #endif tp->t_stats_gput_prev = gput; } tp->t_flags &= ~TF_GPUTINPROG; /* * Now are we app limited now and there is space from where we * were to where we want to go? * * We don't do the other case i.e. non-applimited here since * the next send will trigger us picking up the missing data. */ if (rack->r_ctl.rc_first_appl && TCPS_HAVEESTABLISHED(tp->t_state) && rack->r_ctl.rc_app_limited_cnt && (SEQ_GT(rack->r_ctl.rc_first_appl->r_start, th_ack)) && ((rack->r_ctl.rc_first_appl->r_end - th_ack) > max(rc_init_window(rack), (MIN_GP_WIN * segsiz)))) { /* * Yep there is enough outstanding to make a measurement here. */ struct rack_sendmap *rsm; rack->r_ctl.rc_gp_lowrtt = 0xffffffff; rack->r_ctl.rc_gp_high_rwnd = rack->rc_tp->snd_wnd; tp->gput_ts = tcp_tv_to_usectick(&rack->r_ctl.act_rcv_time); rack->app_limited_needs_set = 0; tp->gput_seq = th_ack; if (rack->in_probe_rtt) rack->measure_saw_probe_rtt = 1; else if ((rack->measure_saw_probe_rtt) && (SEQ_GEQ(tp->gput_seq, rack->r_ctl.rc_probertt_sndmax_atexit))) rack->measure_saw_probe_rtt = 0; if ((rack->r_ctl.rc_first_appl->r_end - th_ack) >= rack_get_measure_window(tp, rack)) { /* There is a full window to gain info from */ tp->gput_ack = tp->gput_seq + rack_get_measure_window(tp, rack); } else { /* We can only measure up to the applimited point */ tp->gput_ack = tp->gput_seq + (rack->r_ctl.rc_first_appl->r_end - th_ack); if ((tp->gput_ack - tp->gput_seq) < (MIN_GP_WIN * segsiz)) { /* * We don't have enough to make a measurement. */ tp->t_flags &= ~TF_GPUTINPROG; rack_log_pacing_delay_calc(rack, tp->gput_ack, tp->gput_seq, 0, 0, 0, 6, __LINE__, NULL, quality); return; } } if (tp->t_state >= TCPS_FIN_WAIT_1) { /* * We will get no more data into the SB * this means we need to have the data available * before we start a measurement. */ if (sbavail(&tptosocket(tp)->so_snd) < (tp->gput_ack - tp->gput_seq)) { /* Nope not enough data. */ return; } } tp->t_flags |= TF_GPUTINPROG; /* * Now we need to find the timestamp of the send at tp->gput_seq * for the send based measurement. */ rack->r_ctl.rc_gp_cumack_ts = 0; rsm = tqhash_find(rack->r_ctl.tqh, tp->gput_seq); if (rsm) { /* Ok send-based limit is set */ if (SEQ_LT(rsm->r_start, tp->gput_seq)) { /* * Move back to include the earlier part * so our ack time lines up right (this may * make an overlapping measurement but thats * ok). */ tp->gput_seq = rsm->r_start; } if (rsm->r_flags & RACK_ACKED) { struct rack_sendmap *nrsm; tp->gput_ts = (uint32_t)rsm->r_ack_arrival; tp->gput_seq = rsm->r_end; nrsm = tqhash_next(rack->r_ctl.tqh, rsm); if (nrsm) rsm = nrsm; else { rack->app_limited_needs_set = 1; } } else rack->app_limited_needs_set = 1; /* We always go from the first send */ rack->r_ctl.rc_gp_output_ts = rsm->r_tim_lastsent[0]; } else { /* * If we don't find the rsm due to some * send-limit set the current time, which * basically disables the send-limit. */ struct timeval tv; microuptime(&tv); rack->r_ctl.rc_gp_output_ts = rack_to_usec_ts(&tv); } rack_tend_gp_marks(tp, rack); rack_log_pacing_delay_calc(rack, tp->gput_seq, tp->gput_ack, (uint64_t)rsm, tp->gput_ts, (((uint64_t)rack->r_ctl.rc_app_limited_cnt << 32) | (uint64_t)rack->r_ctl.rc_gp_output_ts), 9, __LINE__, rsm, quality); rack_log_gpset(rack, tp->gput_ack, 0, 0, __LINE__, 1, NULL); } else { /* * To make sure proper timestamp merging occurs, we need to clear * all GP marks if we don't start a measurement. */ rack_clear_gp_marks(tp, rack); } } /* * CC wrapper hook functions */ static void rack_ack_received(struct tcpcb *tp, struct tcp_rack *rack, uint32_t th_ack, uint16_t nsegs, uint16_t type, int32_t recovery) { uint32_t prior_cwnd, acked; struct tcp_log_buffer *lgb = NULL; uint8_t labc_to_use, quality; INP_WLOCK_ASSERT(tptoinpcb(tp)); tp->t_ccv.nsegs = nsegs; acked = tp->t_ccv.bytes_this_ack = (th_ack - tp->snd_una); if ((recovery) && (rack->r_ctl.rc_early_recovery_segs)) { uint32_t max; max = rack->r_ctl.rc_early_recovery_segs * ctf_fixed_maxseg(tp); if (tp->t_ccv.bytes_this_ack > max) { tp->t_ccv.bytes_this_ack = max; } } #ifdef STATS stats_voi_update_abs_s32(tp->t_stats, VOI_TCP_CALCFRWINDIFF, ((int32_t)rack->r_ctl.cwnd_to_use) - tp->snd_wnd); #endif if ((th_ack == tp->snd_max) && rack->lt_bw_up) { /* We will ack all, time * to end any lt_bw_up we * have running until something * new is sent. */ struct timeval tv; rack->r_ctl.lt_bw_bytes += (tp->snd_max - rack->r_ctl.lt_seq); rack->r_ctl.lt_seq = tp->snd_max; (void)tcp_get_usecs(&tv); rack->r_ctl.lt_bw_time += (tcp_tv_to_lusectick(&tv) - rack->r_ctl.lt_timemark); rack->lt_bw_up = 0; } quality = RACK_QUALITY_NONE; if ((tp->t_flags & TF_GPUTINPROG) && rack_enough_for_measurement(tp, rack, th_ack, &quality)) { /* Measure the Goodput */ rack_do_goodput_measurement(tp, rack, th_ack, __LINE__, quality); } /* Which way our we limited, if not cwnd limited no advance in CA */ if (tp->snd_cwnd <= tp->snd_wnd) tp->t_ccv.flags |= CCF_CWND_LIMITED; else tp->t_ccv.flags &= ~CCF_CWND_LIMITED; if (tp->snd_cwnd > tp->snd_ssthresh) { tp->t_bytes_acked += min(tp->t_ccv.bytes_this_ack, nsegs * V_tcp_abc_l_var * ctf_fixed_maxseg(tp)); /* For the setting of a window past use the actual scwnd we are using */ if (tp->t_bytes_acked >= rack->r_ctl.cwnd_to_use) { tp->t_bytes_acked -= rack->r_ctl.cwnd_to_use; tp->t_ccv.flags |= CCF_ABC_SENTAWND; } } else { tp->t_ccv.flags &= ~CCF_ABC_SENTAWND; tp->t_bytes_acked = 0; } prior_cwnd = tp->snd_cwnd; if ((recovery == 0) || (rack_max_abc_post_recovery == 0) || rack->r_use_labc_for_rec || (rack_client_low_buf && rack->client_bufferlvl && (rack->client_bufferlvl < rack_client_low_buf))) labc_to_use = rack->rc_labc; else labc_to_use = rack_max_abc_post_recovery; if (rack_verbose_logging && tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.flex1 = th_ack; log.u_bbr.flex2 = tp->t_ccv.flags; log.u_bbr.flex3 = tp->t_ccv.bytes_this_ack; log.u_bbr.flex4 = tp->t_ccv.nsegs; log.u_bbr.flex5 = labc_to_use; log.u_bbr.flex6 = prior_cwnd; log.u_bbr.flex7 = V_tcp_do_newsack; log.u_bbr.flex8 = 1; lgb = tcp_log_event(tp, NULL, NULL, NULL, BBR_LOG_CWND, 0, 0, &log, false, NULL, __func__, __LINE__,&tv); } if (CC_ALGO(tp)->ack_received != NULL) { /* XXXLAS: Find a way to live without this */ tp->t_ccv.curack = th_ack; tp->t_ccv.labc = labc_to_use; tp->t_ccv.flags |= CCF_USE_LOCAL_ABC; CC_ALGO(tp)->ack_received(&tp->t_ccv, type); } if (lgb) { lgb->tlb_stackinfo.u_bbr.flex6 = tp->snd_cwnd; } if (rack->r_must_retran) { if (SEQ_GEQ(th_ack, rack->r_ctl.rc_snd_max_at_rto)) { /* * We now are beyond the rxt point so lets disable * the flag. */ rack->r_ctl.rc_out_at_rto = 0; rack->r_must_retran = 0; } else if ((prior_cwnd + ctf_fixed_maxseg(tp)) <= tp->snd_cwnd) { /* * Only decrement the rc_out_at_rto if the cwnd advances * at least a whole segment. Otherwise next time the peer * acks, we won't be able to send this generaly happens * when we are in Congestion Avoidance. */ if (acked <= rack->r_ctl.rc_out_at_rto){ rack->r_ctl.rc_out_at_rto -= acked; } else { rack->r_ctl.rc_out_at_rto = 0; } } } #ifdef STATS stats_voi_update_abs_ulong(tp->t_stats, VOI_TCP_LCWIN, rack->r_ctl.cwnd_to_use); #endif if (rack->r_ctl.rc_rack_largest_cwnd < rack->r_ctl.cwnd_to_use) { rack->r_ctl.rc_rack_largest_cwnd = rack->r_ctl.cwnd_to_use; } } static void tcp_rack_partialack(struct tcpcb *tp) { struct tcp_rack *rack; rack = (struct tcp_rack *)tp->t_fb_ptr; INP_WLOCK_ASSERT(tptoinpcb(tp)); /* * If we are doing PRR and have enough * room to send we are pacing and prr * is disabled we will want to see if we * can send data (by setting r_wanted_output to * true). */ if ((rack->r_ctl.rc_prr_sndcnt > 0) || rack->rack_no_prr) rack->r_wanted_output = 1; } static inline void rack_set_most_aggr(struct tcp_rack *rack) { rack->r_fill_less_agg = 0; /* Once the cwnd as been clamped we don't do fill_cw */ if (rack->r_cwnd_was_clamped == 0) rack->rc_pace_to_cwnd = 1; rack->r_pacing_discount = 0; } static inline void rack_limit_fillcw(struct tcp_rack *rack) { rack->r_fill_less_agg = 1; /* Once the cwnd as been clamped we don't do fill_cw */ if (rack->r_cwnd_was_clamped == 0) rack->rc_pace_to_cwnd = 1; rack->r_pacing_discount = 0; } static inline void rack_disable_fillcw(struct tcp_rack *rack) { rack->r_fill_less_agg = 1; rack->rc_pace_to_cwnd = 0; rack->r_pacing_discount = 0; } static void rack_client_buffer_level_set(struct tcp_rack *rack) { /* * Only if DGP is on do we do anything that * changes stack behavior. If DGP is off all * we will do is issue a BB log (if BB logging is * on) and return. */ if (rack->dgp_on == 0) { rack_log_pacing_delay_calc(rack, 0, rack->client_bufferlvl, 0, 0, 0, 30, __LINE__, NULL, 0); return; } if (IN_RECOVERY(rack->rc_tp->t_flags) && rack->r_ctl.full_dgp_in_rec) { goto set_most_agg; } /* * We are in DGP so what setting should we * apply based on where the client is? */ switch(rack->r_ctl.rc_dgp_bl_agg) { default: case DGP_LEVEL0: set_most_agg: rack_set_most_aggr(rack); break; case DGP_LEVEL1: if (rack->client_bufferlvl == 4) rack_limit_fillcw(rack); else if (rack->client_bufferlvl == 5) rack_disable_fillcw(rack); else rack_set_most_aggr(rack); break; case DGP_LEVEL2: if (rack->client_bufferlvl == 3) rack_limit_fillcw(rack); else if (rack->client_bufferlvl == 4) rack_disable_fillcw(rack); else if (rack->client_bufferlvl == 5) { rack_disable_fillcw(rack); rack->r_pacing_discount = 1; rack->r_ctl.pacing_discount_amm = 1; } else rack_set_most_aggr(rack); break; case DGP_LEVEL3: if (rack->client_bufferlvl == 2) rack_limit_fillcw(rack); else if (rack->client_bufferlvl == 3) rack_disable_fillcw(rack); else if (rack->client_bufferlvl == 4) { rack_disable_fillcw(rack); rack->r_pacing_discount = 1; rack->r_ctl.pacing_discount_amm = 1; } else if (rack->client_bufferlvl == 5) { rack_disable_fillcw(rack); rack->r_pacing_discount = 1; rack->r_ctl.pacing_discount_amm = 2; } else rack_set_most_aggr(rack); break; } rack_log_pacing_delay_calc(rack, rack->r_ctl.rc_dgp_bl_agg, rack->client_bufferlvl, 0, 0, 0, 30, __LINE__, NULL, 0); } static void do_rack_check_for_unclamp(struct tcpcb *tp, struct tcp_rack *rack) { /* * Can we unclamp. We unclamp if more than * N rounds have transpired with no loss. */ uint64_t snds, rxts, rxt_per; uint32_t rnds; rnds = rack->r_ctl.current_round - rack->r_ctl.last_rnd_rxt_clamped; if ((rack_unclamp_round_thresh > 0) && (rnds >= rack_unclamp_round_thresh)) { snds = tp->t_sndbytes - rack->r_ctl.last_sndbytes; KASSERT ((snds > 0), ("rack:%p tp:%p snds:%ju is 0", rack, tp, (uintmax_t)snds)); rxts = tp->t_snd_rxt_bytes - rack->r_ctl.last_snd_rxt_bytes; rxt_per = rxts * 1000; rxt_per /= snds; if ((uint32_t)rxt_per <= rack_unclamp_rxt_thresh) { /* Unclamp */ if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.flex3 = rnds; log.u_bbr.flex4 = rack_unclamp_round_thresh; log.u_bbr.flex5 = (uint32_t)rxt_per; log.u_bbr.flex8 = 6; log.u_bbr.pkt_epoch = rack->r_ctl.rc_pace_max_segs; log.u_bbr.bbr_state = rack->rc_pace_to_cwnd; log.u_bbr.delivered = rack->r_ctl.num_of_clamps_applied; log.u_bbr.applimited = rack->r_ctl.max_clamps; log.u_bbr.epoch = rack->r_ctl.clamp_options; log.u_bbr.cur_del_rate = rxts; log.u_bbr.bw_inuse = rack_get_lt_bw(rack); log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); log.u_bbr.lt_epoch = (uint32_t)((rack->r_ctl.gp_bw >> 32) & 0x00000000ffffffff); log.u_bbr.pkts_out = (uint32_t)(rack->r_ctl.gp_bw & 0x00000000ffffffff); tcp_log_event(tp, NULL, NULL, NULL, BBR_LOG_CWND, 0, 0, &log, false, NULL, NULL, 0, &tv); } rack->r_ctl.num_of_clamps_applied = 0; rack->r_cwnd_was_clamped = 0; rack->excess_rxt_on = 1; if (rack->r_ctl.clamp_options) { /* * We only allow fillcw to be toggled * if you are setting a max seg too. */ if (rack->r_ctl.clamp_options & 0x1) { if ((rack->rc_pace_to_cwnd == 0) && (rack->dgp_on == 0)) { /* turn on fill cw for non-dgp*/ rack->rc_pace_to_cwnd = 0; } else if ((rack->dgp_on == 1) && (rack->rc_pace_to_cwnd == 1)) { /* For DGP we want it off */ rack->rc_pace_to_cwnd = 1; } } } if (rack->dgp_on) { /* Reset all multipliers to 100.0 so just the measured bw */ /* Crash any per boosts down to 100% */ rack->r_ctl.rack_per_of_gp_rec = 100; rack->r_ctl.rack_per_of_gp_ss = 100; rack->r_ctl.rack_per_of_gp_ca = 100; /* Set in an upper bound for ss/ca % increase */ rack->r_ctl.rack_per_upper_bound_ss = (uint8_t)rack_per_upper_bound_ss; rack->r_ctl.rack_per_upper_bound_ca = (uint8_t)rack_per_upper_bound_ca; } } } } static void do_rack_excess_rxt(struct tcpcb *tp, struct tcp_rack *rack) { /* * Rack excess rxt accounting is turned on. If we * are above a threshold of rxt's in at least N * rounds, then back off the cwnd and ssthresh * to fit into the long-term b/w. */ uint64_t snds, rxts, rxt_per, lt_bw, bdp; uint32_t rnds, new_cwnd, new_ssthresh, rtt, shared_cwnd_was_enabled = 0; /* Is it shut off by 0 rounds? */ if (rack_rxt_min_rnds == 0) return; if ((rack->r_ctl.max_clamps > 0) && (rack->r_ctl.num_of_clamps_applied >= rack->r_ctl.max_clamps)) { /* * The idea, if max_clamps is set, is that if clamping it * N times did not work again, then there is no sense * clamping it again. The link is just a lossy link and * our clamps are doing no good. Turn it off so we don't come * back here again. */ rack->excess_rxt_on = 0; rack->r_cwnd_was_clamped = 0; rack->r_ctl.num_of_clamps_applied = 0; return; } snds = tp->t_sndbytes - rack->r_ctl.last_sndbytes; rxts = tp->t_snd_rxt_bytes - rack->r_ctl.last_snd_rxt_bytes; rnds = rack->r_ctl.current_round - rack->r_ctl.last_rnd_rxt_clamped; /* Has enough rounds progressed for us to re-measure? */ if ((rnds >= rack_rxt_min_rnds) && (rack->r_ctl.rxt_threshold > 0)){ rxt_per = rxts * 1000; rxt_per /= snds; if (rxt_per >= rack->r_ctl.rxt_threshold) { /* * Action required: * We are above our excess retransmit level, lets * cut down the cwnd and ssthresh to match the long-term * b/w we are getting. */ /* First disable scwnd if enabled */ #ifdef NETFLIX_SHARED_CWND rack->rack_enable_scwnd = 0; if (rack->r_ctl.rc_scw) { uint32_t limit; shared_cwnd_was_enabled = 1; if (rack->r_limit_scw) limit = max(1, rack->r_ctl.rc_lowest_us_rtt); else limit = 0; tcp_shared_cwnd_free_full(tp, rack->r_ctl.rc_scw, rack->r_ctl.rc_scw_index, limit); rack->r_ctl.rc_scw = NULL; } #endif /* Calculate what the cwnd and ssthresh should be */ tcp_trace_point(rack->rc_tp, TCP_TP_EXCESS_RXT); lt_bw = rack_get_lt_bw(rack); if (lt_bw == 0) { /* * No lt_bw, lets chop things to one MSS * and the ssthresh to the iwnd. */ reset_to_iw: new_cwnd = min(ctf_fixed_maxseg(tp), rack->r_ctl.rc_pace_min_segs); new_ssthresh = tcp_compute_initwnd(tcp_maxseg(tp)); } else { rtt = rack->rc_rack_rtt; if (rtt == 0) { /* If we have no rack_rtt drop to the IW situation */ goto reset_to_iw; } bdp = lt_bw * (uint64_t)rtt; bdp /= HPTS_USEC_IN_SEC; new_cwnd = (uint32_t)bdp; new_ssthresh = new_cwnd - 1; if (new_cwnd < ctf_fixed_maxseg(tp)) { /* Rock bottom, goto IW settings */ goto reset_to_iw; } } rack->r_cwnd_was_clamped = 1; rack->r_ctl.num_of_clamps_applied++; /* Reset the counter fromn now */ tp->t_bytes_acked = 0; /* * Now what about options? * We look at the bottom 8 bits: * F = fill cw bit (toggle it if set) * S = Segment bits * M = set max segment bit * * SSSS SSMF */ if (rack->r_ctl.clamp_options) { if (rack->r_ctl.clamp_options & 0x1) { if ((rack->rc_pace_to_cwnd == 0) && (rack->dgp_on == 0)) { /* turn on fill cw for non-dgp*/ rack->rc_pace_to_cwnd = 1; } else if ((rack->dgp_on == 1) && (rack->rc_pace_to_cwnd == 1)) { /* For DGP we want it off */ rack->rc_pace_to_cwnd = 0; } } } if (rack->dgp_on) { /* Reset all multipliers to 100.0 so just the measured bw */ /* Crash any per boosts down to 100% */ rack->r_ctl.rack_per_of_gp_rec = 100; rack->r_ctl.rack_per_of_gp_ss = 100; rack->r_ctl.rack_per_of_gp_ca = 100; /* Set in an upper bound for ss/ca % increase */ rack->r_ctl.rack_per_upper_bound_ss = (uint8_t)rack_clamp_ss_upper; rack->r_ctl.rack_per_upper_bound_ca = (uint8_t)rack_clamp_ca_upper; /* Now move to the lt_bw */ rack->r_ctl.gp_bw = lt_bw; rack->rc_gp_filled = 1; rack->r_ctl.num_measurements = RACK_REQ_AVG; } if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.flex1 = new_cwnd; log.u_bbr.flex2 = new_ssthresh; log.u_bbr.flex3 = rnds; log.u_bbr.flex4 = rack_rxt_min_rnds; log.u_bbr.flex5 = rtt; log.u_bbr.flex6 = shared_cwnd_was_enabled; log.u_bbr.flex8 = 5; log.u_bbr.pkt_epoch = rack->r_ctl.rc_pace_max_segs; log.u_bbr.bbr_state = rack->rc_pace_to_cwnd; log.u_bbr.delivered = rack->r_ctl.num_of_clamps_applied; log.u_bbr.applimited = rack->r_ctl.max_clamps; log.u_bbr.epoch = rack->r_ctl.clamp_options; log.u_bbr.cur_del_rate = rxts; log.u_bbr.delRate = snds; log.u_bbr.rttProp = rack->r_ctl.rxt_threshold; log.u_bbr.bw_inuse = lt_bw; log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); log.u_bbr.lt_epoch = (uint32_t)((rack->r_ctl.gp_bw >> 32) & 0x00000000ffffffff); log.u_bbr.pkts_out = (uint32_t)(rack->r_ctl.gp_bw & 0x00000000ffffffff); tcp_log_event(tp, NULL, NULL, NULL, BBR_LOG_CWND, 0, 0, &log, false, NULL, NULL, 0, &tv); } /* Update our point where we did it */ if (rack->r_ctl.already_had_a_excess == 0) { rack->r_ctl.already_had_a_excess = 1; counter_u64_add(rack_rxt_clamps_cwnd_uniq, 1); } counter_u64_add(rack_rxt_clamps_cwnd, 1); rack->r_ctl.last_sndbytes = tp->t_sndbytes; rack->r_ctl.last_snd_rxt_bytes = tp->t_snd_rxt_bytes; rack->r_ctl.last_rnd_rxt_clamped = rack->r_ctl.current_round; if (new_cwnd < tp->snd_cwnd) tp->snd_cwnd = new_cwnd; if (new_ssthresh < tp->snd_ssthresh) tp->snd_ssthresh = new_ssthresh; } } } static void rack_post_recovery(struct tcpcb *tp, uint32_t th_ack) { struct tcp_rack *rack; uint32_t orig_cwnd; orig_cwnd = tp->snd_cwnd; INP_WLOCK_ASSERT(tptoinpcb(tp)); rack = (struct tcp_rack *)tp->t_fb_ptr; /* only alert CC if we alerted when we entered */ if (CC_ALGO(tp)->post_recovery != NULL) { tp->t_ccv.curack = th_ack; CC_ALGO(tp)->post_recovery(&tp->t_ccv); if (tp->snd_cwnd < tp->snd_ssthresh) { /* * Rack has burst control and pacing * so lets not set this any lower than * snd_ssthresh per RFC-6582 (option 2). */ tp->snd_cwnd = tp->snd_ssthresh; } } if (rack_verbose_logging && tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.flex1 = th_ack; log.u_bbr.flex2 = tp->t_ccv.flags; log.u_bbr.flex3 = tp->t_ccv.bytes_this_ack; log.u_bbr.flex4 = tp->t_ccv.nsegs; log.u_bbr.flex5 = V_tcp_abc_l_var; log.u_bbr.flex6 = orig_cwnd; log.u_bbr.flex7 = V_tcp_do_newsack; log.u_bbr.pkts_out = rack->r_ctl.rc_prr_sndcnt; log.u_bbr.flex8 = 2; tcp_log_event(tp, NULL, NULL, NULL, BBR_LOG_CWND, 0, 0, &log, false, NULL, __func__, __LINE__, &tv); } if ((rack->rack_no_prr == 0) && (rack->no_prr_addback == 0) && (rack->r_ctl.rc_prr_sndcnt > 0)) { /* * Suck the next prr cnt back into cwnd, but * only do that if we are not application limited. */ if (ctf_outstanding(tp) <= sbavail(&tptosocket(tp)->so_snd)) { /* * We are allowed to add back to the cwnd the amount we did * not get out if: * a) no_prr_addback is off. * b) we are not app limited * c) we are doing prr * * d) it is bounded by rack_prr_addbackmax (if addback is 0, then none). */ tp->snd_cwnd += min((ctf_fixed_maxseg(tp) * rack_prr_addbackmax), rack->r_ctl.rc_prr_sndcnt); } rack->r_ctl.rc_prr_sndcnt = 0; rack_log_to_prr(rack, 1, 0, __LINE__); } rack_log_to_prr(rack, 14, orig_cwnd, __LINE__); tp->snd_recover = tp->snd_una; if (rack->r_ctl.dsack_persist) { rack->r_ctl.dsack_persist--; if (rack->r_ctl.num_dsack && (rack->r_ctl.dsack_persist == 0)) { rack->r_ctl.num_dsack = 0; } rack_log_dsack_event(rack, 1, __LINE__, 0, 0); } EXIT_RECOVERY(tp->t_flags); if (rack->r_ctl.full_dgp_in_rec) rack_client_buffer_level_set(rack); } static void rack_cong_signal(struct tcpcb *tp, uint32_t type, uint32_t ack, int line) { struct tcp_rack *rack; uint32_t ssthresh_enter, cwnd_enter, in_rec_at_entry, orig_cwnd; INP_WLOCK_ASSERT(tptoinpcb(tp)); #ifdef STATS stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_CSIG, type); #endif if (IN_RECOVERY(tp->t_flags) == 0) { in_rec_at_entry = 0; ssthresh_enter = tp->snd_ssthresh; cwnd_enter = tp->snd_cwnd; } else in_rec_at_entry = 1; rack = (struct tcp_rack *)tp->t_fb_ptr; switch (type) { case CC_NDUPACK: tp->t_flags &= ~TF_WASFRECOVERY; tp->t_flags &= ~TF_WASCRECOVERY; if (!IN_FASTRECOVERY(tp->t_flags)) { if (rack->dgp_on && rack->r_cwnd_was_clamped) { /* Reset the gains so that on exit we will be softer longer */ rack->r_ctl.rack_per_of_gp_rec = 100; rack->r_ctl.rack_per_of_gp_ss = 98; rack->r_ctl.rack_per_of_gp_ca = 98; } rack->r_ctl.rc_prr_delivered = 0; rack->r_ctl.rc_prr_out = 0; rack->r_fast_output = 0; if (rack->rack_no_prr == 0) { rack->r_ctl.rc_prr_sndcnt = ctf_fixed_maxseg(tp); rack_log_to_prr(rack, 2, in_rec_at_entry, line); } rack->r_ctl.rc_prr_recovery_fs = tp->snd_max - tp->snd_una; tp->snd_recover = tp->snd_max; if (tp->t_flags2 & TF2_ECN_PERMIT) tp->t_flags2 |= TF2_ECN_SND_CWR; } break; case CC_ECN: if (!IN_CONGRECOVERY(tp->t_flags) || /* * Allow ECN reaction on ACK to CWR, if * that data segment was also CE marked. */ SEQ_GEQ(ack, tp->snd_recover)) { EXIT_CONGRECOVERY(tp->t_flags); KMOD_TCPSTAT_INC(tcps_ecn_rcwnd); rack->r_fast_output = 0; tp->snd_recover = tp->snd_max + 1; if (tp->t_flags2 & TF2_ECN_PERMIT) tp->t_flags2 |= TF2_ECN_SND_CWR; } break; case CC_RTO: tp->t_dupacks = 0; tp->t_bytes_acked = 0; rack->r_fast_output = 0; EXIT_RECOVERY(tp->t_flags); tp->snd_ssthresh = max(2, min(tp->snd_wnd, rack->r_ctl.cwnd_to_use) / 2 / ctf_fixed_maxseg(tp)) * ctf_fixed_maxseg(tp); orig_cwnd = tp->snd_cwnd; tp->snd_cwnd = ctf_fixed_maxseg(tp); rack_log_to_prr(rack, 16, orig_cwnd, line); if (tp->t_flags2 & TF2_ECN_PERMIT) tp->t_flags2 |= TF2_ECN_SND_CWR; break; case CC_RTO_ERR: KMOD_TCPSTAT_INC(tcps_sndrexmitbad); /* RTO was unnecessary, so reset everything. */ tp->snd_cwnd = tp->snd_cwnd_prev; tp->snd_ssthresh = tp->snd_ssthresh_prev; tp->snd_recover = tp->snd_recover_prev; if (tp->t_flags & TF_WASFRECOVERY) { ENTER_FASTRECOVERY(tp->t_flags); tp->t_flags &= ~TF_WASFRECOVERY; } if (tp->t_flags & TF_WASCRECOVERY) { ENTER_CONGRECOVERY(tp->t_flags); tp->t_flags &= ~TF_WASCRECOVERY; } tp->snd_nxt = tp->snd_max; tp->t_badrxtwin = 0; break; } if ((CC_ALGO(tp)->cong_signal != NULL) && (type != CC_RTO)){ tp->t_ccv.curack = ack; CC_ALGO(tp)->cong_signal(&tp->t_ccv, type); } if ((in_rec_at_entry == 0) && IN_RECOVERY(tp->t_flags)) { rack_log_to_prr(rack, 15, cwnd_enter, line); if (rack->r_ctl.full_dgp_in_rec) rack_client_buffer_level_set(rack); rack->r_ctl.dsack_byte_cnt = 0; rack->r_ctl.retran_during_recovery = 0; rack->r_ctl.rc_cwnd_at_erec = cwnd_enter; rack->r_ctl.rc_ssthresh_at_erec = ssthresh_enter; rack->r_ent_rec_ns = 1; } } static inline void rack_cc_after_idle(struct tcp_rack *rack, struct tcpcb *tp) { uint32_t i_cwnd; INP_WLOCK_ASSERT(tptoinpcb(tp)); if (CC_ALGO(tp)->after_idle != NULL) CC_ALGO(tp)->after_idle(&tp->t_ccv); if (tp->snd_cwnd == 1) i_cwnd = tp->t_maxseg; /* SYN(-ACK) lost */ else i_cwnd = rc_init_window(rack); /* * Being idle is no different than the initial window. If the cc * clamps it down below the initial window raise it to the initial * window. */ if (tp->snd_cwnd < i_cwnd) { tp->snd_cwnd = i_cwnd; } } /* * Indicate whether this ack should be delayed. We can delay the ack if * following conditions are met: * - There is no delayed ack timer in progress. * - Our last ack wasn't a 0-sized window. We never want to delay * the ack that opens up a 0-sized window. * - LRO wasn't used for this segment. We make sure by checking that the * segment size is not larger than the MSS. * - Delayed acks are enabled or this is a half-synchronized T/TCP * connection. */ #define DELAY_ACK(tp, tlen) \ (((tp->t_flags & TF_RXWIN0SENT) == 0) && \ ((tp->t_flags & TF_DELACK) == 0) && \ (tlen <= tp->t_maxseg) && \ (tp->t_delayed_ack || (tp->t_flags & TF_NEEDSYN))) static struct rack_sendmap * rack_find_lowest_rsm(struct tcp_rack *rack) { struct rack_sendmap *rsm; /* * Walk the time-order transmitted list looking for an rsm that is * not acked. This will be the one that was sent the longest time * ago that is still outstanding. */ TAILQ_FOREACH(rsm, &rack->r_ctl.rc_tmap, r_tnext) { if (rsm->r_flags & RACK_ACKED) { continue; } goto finish; } finish: return (rsm); } static struct rack_sendmap * rack_find_high_nonack(struct tcp_rack *rack, struct rack_sendmap *rsm) { struct rack_sendmap *prsm; /* * Walk the sequence order list backward until we hit and arrive at * the highest seq not acked. In theory when this is called it * should be the last segment (which it was not). */ prsm = rsm; TQHASH_FOREACH_REVERSE_FROM(prsm, rack->r_ctl.tqh) { if (prsm->r_flags & (RACK_ACKED | RACK_HAS_FIN)) { continue; } return (prsm); } return (NULL); } static uint32_t rack_calc_thresh_rack(struct tcp_rack *rack, uint32_t srtt, uint32_t cts) { int32_t lro; uint32_t thresh; /* * lro is the flag we use to determine if we have seen reordering. * If it gets set we have seen reordering. The reorder logic either * works in one of two ways: * * If reorder-fade is configured, then we track the last time we saw * re-ordering occur. If we reach the point where enough time as * passed we no longer consider reordering has occuring. * * Or if reorder-face is 0, then once we see reordering we consider * the connection to alway be subject to reordering and just set lro * to 1. * * In the end if lro is non-zero we add the extra time for * reordering in. */ if (srtt == 0) srtt = 1; if (rack->r_ctl.rc_reorder_ts) { if (rack->r_ctl.rc_reorder_fade) { if (SEQ_GEQ(cts, rack->r_ctl.rc_reorder_ts)) { lro = cts - rack->r_ctl.rc_reorder_ts; if (lro == 0) { /* * No time as passed since the last * reorder, mark it as reordering. */ lro = 1; } } else { /* Negative time? */ lro = 0; } if (lro > rack->r_ctl.rc_reorder_fade) { /* Turn off reordering seen too */ rack->r_ctl.rc_reorder_ts = 0; lro = 0; } } else { /* Reodering does not fade */ lro = 1; } } else { lro = 0; } if (rack->rc_rack_tmr_std_based == 0) { thresh = srtt + rack->r_ctl.rc_pkt_delay; } else { /* Standards based pkt-delay is 1/4 srtt */ thresh = srtt + (srtt >> 2); } if (lro && (rack->rc_rack_tmr_std_based == 0)) { /* It must be set, if not you get 1/4 rtt */ if (rack->r_ctl.rc_reorder_shift) thresh += (srtt >> rack->r_ctl.rc_reorder_shift); else thresh += (srtt >> 2); } if (rack->rc_rack_use_dsack && lro && (rack->r_ctl.num_dsack > 0)) { /* * We only increase the reordering window if we * have seen reordering we have a DSACK count. */ thresh += rack->r_ctl.num_dsack * (srtt >> 2); rack_log_dsack_event(rack, 4, __LINE__, srtt, thresh); } /* SRTT * 2 is the ceiling */ if (thresh > (srtt * 2)) { thresh = srtt * 2; } /* And we don't want it above the RTO max either */ if (thresh > rack_rto_max) { thresh = rack_rto_max; } rack_log_dsack_event(rack, 6, __LINE__, srtt, thresh); return (thresh); } static uint32_t rack_calc_thresh_tlp(struct tcpcb *tp, struct tcp_rack *rack, struct rack_sendmap *rsm, uint32_t srtt) { struct rack_sendmap *prsm; uint32_t thresh, len; int segsiz; if (srtt == 0) srtt = 1; if (rack->r_ctl.rc_tlp_threshold) thresh = srtt + (srtt / rack->r_ctl.rc_tlp_threshold); else thresh = (srtt * 2); /* Get the previous sent packet, if any */ segsiz = min(ctf_fixed_maxseg(tp), rack->r_ctl.rc_pace_min_segs); len = rsm->r_end - rsm->r_start; if (rack->rack_tlp_threshold_use == TLP_USE_ID) { /* Exactly like the ID */ if (((tp->snd_max - tp->snd_una) - rack->r_ctl.rc_sacked + rack->r_ctl.rc_holes_rxt) <= segsiz) { uint32_t alt_thresh; /* * Compensate for delayed-ack with the d-ack time. */ alt_thresh = srtt + (srtt / 2) + rack_delayed_ack_time; if (alt_thresh > thresh) thresh = alt_thresh; } } else if (rack->rack_tlp_threshold_use == TLP_USE_TWO_ONE) { /* 2.1 behavior */ prsm = TAILQ_PREV(rsm, rack_head, r_tnext); if (prsm && (len <= segsiz)) { /* * Two packets outstanding, thresh should be (2*srtt) + * possible inter-packet delay (if any). */ uint32_t inter_gap = 0; int idx, nidx; idx = rsm->r_rtr_cnt - 1; nidx = prsm->r_rtr_cnt - 1; if (rsm->r_tim_lastsent[nidx] >= prsm->r_tim_lastsent[idx]) { /* Yes it was sent later (or at the same time) */ inter_gap = rsm->r_tim_lastsent[idx] - prsm->r_tim_lastsent[nidx]; } thresh += inter_gap; } else if (len <= segsiz) { /* * Possibly compensate for delayed-ack. */ uint32_t alt_thresh; alt_thresh = srtt + (srtt / 2) + rack_delayed_ack_time; if (alt_thresh > thresh) thresh = alt_thresh; } } else if (rack->rack_tlp_threshold_use == TLP_USE_TWO_TWO) { /* 2.2 behavior */ if (len <= segsiz) { uint32_t alt_thresh; /* * Compensate for delayed-ack with the d-ack time. */ alt_thresh = srtt + (srtt / 2) + rack_delayed_ack_time; if (alt_thresh > thresh) thresh = alt_thresh; } } /* Not above an RTO */ if (thresh > tp->t_rxtcur) { thresh = tp->t_rxtcur; } /* Not above a RTO max */ if (thresh > rack_rto_max) { thresh = rack_rto_max; } /* Apply user supplied min TLP */ if (thresh < rack_tlp_min) { thresh = rack_tlp_min; } return (thresh); } static uint32_t rack_grab_rtt(struct tcpcb *tp, struct tcp_rack *rack) { /* * We want the rack_rtt which is the * last rtt we measured. However if that * does not exist we fallback to the srtt (which * we probably will never do) and then as a last * resort we use RACK_INITIAL_RTO if no srtt is * yet set. */ if (rack->rc_rack_rtt) return (rack->rc_rack_rtt); else if (tp->t_srtt == 0) return (RACK_INITIAL_RTO); return (tp->t_srtt); } static struct rack_sendmap * rack_check_recovery_mode(struct tcpcb *tp, uint32_t tsused) { /* * Check to see that we don't need to fall into recovery. We will * need to do so if our oldest transmit is past the time we should * have had an ack. */ struct tcp_rack *rack; struct rack_sendmap *rsm; int32_t idx; uint32_t srtt, thresh; rack = (struct tcp_rack *)tp->t_fb_ptr; if (tqhash_empty(rack->r_ctl.tqh)) { return (NULL); } rsm = TAILQ_FIRST(&rack->r_ctl.rc_tmap); if (rsm == NULL) return (NULL); if (rsm->r_flags & RACK_ACKED) { rsm = rack_find_lowest_rsm(rack); if (rsm == NULL) return (NULL); } idx = rsm->r_rtr_cnt - 1; srtt = rack_grab_rtt(tp, rack); thresh = rack_calc_thresh_rack(rack, srtt, tsused); if (TSTMP_LT(tsused, ((uint32_t)rsm->r_tim_lastsent[idx]))) { return (NULL); } if ((tsused - ((uint32_t)rsm->r_tim_lastsent[idx])) < thresh) { return (NULL); } /* Ok if we reach here we are over-due and this guy can be sent */ rack_cong_signal(tp, CC_NDUPACK, tp->snd_una, __LINE__); return (rsm); } static uint32_t rack_get_persists_timer_val(struct tcpcb *tp, struct tcp_rack *rack) { int32_t t; int32_t tt; uint32_t ret_val; t = (tp->t_srtt + (tp->t_rttvar << 2)); RACK_TCPT_RANGESET(tt, t * tcp_backoff[tp->t_rxtshift], rack_persist_min, rack_persist_max, rack->r_ctl.timer_slop); rack->r_ctl.rc_hpts_flags |= PACE_TMR_PERSIT; ret_val = (uint32_t)tt; return (ret_val); } static uint32_t rack_timer_start(struct tcpcb *tp, struct tcp_rack *rack, uint32_t cts, int sup_rack) { /* * Start the FR timer, we do this based on getting the first one in * the rc_tmap. Note that if its NULL we must stop the timer. in all * events we need to stop the running timer (if its running) before * starting the new one. */ uint32_t thresh, exp, to, srtt, time_since_sent, tstmp_touse; uint32_t srtt_cur; int32_t idx; int32_t is_tlp_timer = 0; struct rack_sendmap *rsm; if (rack->t_timers_stopped) { /* All timers have been stopped none are to run */ return (0); } if (rack->rc_in_persist) { /* We can't start any timer in persists */ return (rack_get_persists_timer_val(tp, rack)); } rack->rc_on_min_to = 0; if ((tp->t_state < TCPS_ESTABLISHED) || (rack->sack_attack_disable > 0) || ((tp->t_flags & TF_SACK_PERMIT) == 0)) { goto activate_rxt; } rsm = TAILQ_FIRST(&rack->r_ctl.rc_tmap); if ((rsm == NULL) || sup_rack) { /* Nothing on the send map or no rack */ activate_rxt: time_since_sent = 0; rsm = TAILQ_FIRST(&rack->r_ctl.rc_tmap); if (rsm) { /* * Should we discount the RTX timer any? * * We want to discount it the smallest amount. * If a timer (Rack/TLP or RXT) has gone off more * recently thats the discount we want to use (now - timer time). * If the retransmit of the oldest packet was more recent then * we want to use that (now - oldest-packet-last_transmit_time). * */ idx = rsm->r_rtr_cnt - 1; if (TSTMP_GEQ(rack->r_ctl.rc_tlp_rxt_last_time, ((uint32_t)rsm->r_tim_lastsent[idx]))) tstmp_touse = (uint32_t)rack->r_ctl.rc_tlp_rxt_last_time; else tstmp_touse = (uint32_t)rsm->r_tim_lastsent[idx]; if (TSTMP_GT(cts, tstmp_touse)) time_since_sent = cts - tstmp_touse; } if (SEQ_LT(tp->snd_una, tp->snd_max) || sbavail(&tptosocket(tp)->so_snd)) { rack->r_ctl.rc_hpts_flags |= PACE_TMR_RXT; to = tp->t_rxtcur; if (to > time_since_sent) to -= time_since_sent; else to = rack->r_ctl.rc_min_to; if (to == 0) to = 1; /* Special case for KEEPINIT */ if ((TCPS_HAVEESTABLISHED(tp->t_state) == 0) && (TP_KEEPINIT(tp) != 0) && rsm) { /* * We have to put a ceiling on the rxt timer * of the keep-init timeout. */ uint32_t max_time, red; max_time = TICKS_2_USEC(TP_KEEPINIT(tp)); if (TSTMP_GT(cts, (uint32_t)rsm->r_tim_lastsent[0])) { red = (cts - (uint32_t)rsm->r_tim_lastsent[0]); if (red < max_time) max_time -= red; else max_time = 1; } /* Reduce timeout to the keep value if needed */ if (max_time < to) to = max_time; } return (to); } return (0); } if (rsm->r_flags & RACK_ACKED) { rsm = rack_find_lowest_rsm(rack); if (rsm == NULL) { /* No lowest? */ goto activate_rxt; } } if (rack->sack_attack_disable) { /* * We don't want to do * any TLP's if you are an attacker. * Though if you are doing what * is expected you may still have * SACK-PASSED marks. */ goto activate_rxt; } /* Convert from ms to usecs */ if ((rsm->r_flags & RACK_SACK_PASSED) || (rsm->r_flags & RACK_RWND_COLLAPSED) || (rsm->r_dupack >= DUP_ACK_THRESHOLD)) { if ((tp->t_flags & TF_SENTFIN) && ((tp->snd_max - tp->snd_una) == 1) && (rsm->r_flags & RACK_HAS_FIN)) { /* * We don't start a rack timer if all we have is a * FIN outstanding. */ goto activate_rxt; } if ((rack->use_rack_rr == 0) && (IN_FASTRECOVERY(tp->t_flags)) && (rack->rack_no_prr == 0) && (rack->r_ctl.rc_prr_sndcnt < ctf_fixed_maxseg(tp))) { /* * We are not cheating, in recovery and * not enough ack's to yet get our next * retransmission out. * * Note that classified attackers do not * get to use the rack-cheat. */ goto activate_tlp; } srtt = rack_grab_rtt(tp, rack); thresh = rack_calc_thresh_rack(rack, srtt, cts); idx = rsm->r_rtr_cnt - 1; exp = ((uint32_t)rsm->r_tim_lastsent[idx]) + thresh; if (SEQ_GEQ(exp, cts)) { to = exp - cts; if (to < rack->r_ctl.rc_min_to) { to = rack->r_ctl.rc_min_to; if (rack->r_rr_config == 3) rack->rc_on_min_to = 1; } } else { to = rack->r_ctl.rc_min_to; if (rack->r_rr_config == 3) rack->rc_on_min_to = 1; } } else { /* Ok we need to do a TLP not RACK */ activate_tlp: if ((rack->rc_tlp_in_progress != 0) && (rack->r_ctl.rc_tlp_cnt_out >= rack_tlp_limit)) { /* * The previous send was a TLP and we have sent * N TLP's without sending new data. */ goto activate_rxt; } rsm = TAILQ_LAST_FAST(&rack->r_ctl.rc_tmap, rack_sendmap, r_tnext); if (rsm == NULL) { /* We found no rsm to TLP with. */ goto activate_rxt; } if (rsm->r_flags & RACK_HAS_FIN) { /* If its a FIN we dont do TLP */ rsm = NULL; goto activate_rxt; } idx = rsm->r_rtr_cnt - 1; time_since_sent = 0; if (TSTMP_GEQ(((uint32_t)rsm->r_tim_lastsent[idx]), rack->r_ctl.rc_tlp_rxt_last_time)) tstmp_touse = (uint32_t)rsm->r_tim_lastsent[idx]; else tstmp_touse = (uint32_t)rack->r_ctl.rc_tlp_rxt_last_time; if (TSTMP_GT(cts, tstmp_touse)) time_since_sent = cts - tstmp_touse; is_tlp_timer = 1; if (tp->t_srtt) { if ((rack->rc_srtt_measure_made == 0) && (tp->t_srtt == 1)) { /* * If another stack as run and set srtt to 1, * then the srtt was 0, so lets use the initial. */ srtt = RACK_INITIAL_RTO; } else { srtt_cur = tp->t_srtt; srtt = srtt_cur; } } else srtt = RACK_INITIAL_RTO; /* * If the SRTT is not keeping up and the * rack RTT has spiked we want to use * the last RTT not the smoothed one. */ if (rack_tlp_use_greater && tp->t_srtt && (srtt < rack_grab_rtt(tp, rack))) { srtt = rack_grab_rtt(tp, rack); } thresh = rack_calc_thresh_tlp(tp, rack, rsm, srtt); if (thresh > time_since_sent) { to = thresh - time_since_sent; } else { to = rack->r_ctl.rc_min_to; rack_log_alt_to_to_cancel(rack, thresh, /* flex1 */ time_since_sent, /* flex2 */ tstmp_touse, /* flex3 */ rack->r_ctl.rc_tlp_rxt_last_time, /* flex4 */ (uint32_t)rsm->r_tim_lastsent[idx], srtt, idx, 99); } if (to < rack_tlp_min) { to = rack_tlp_min; } if (to > TICKS_2_USEC(TCPTV_REXMTMAX)) { /* * If the TLP time works out to larger than the max * RTO lets not do TLP.. just RTO. */ goto activate_rxt; } } if (is_tlp_timer == 0) { rack->r_ctl.rc_hpts_flags |= PACE_TMR_RACK; } else { rack->r_ctl.rc_hpts_flags |= PACE_TMR_TLP; } if (to == 0) to = 1; return (to); } static void rack_enter_persist(struct tcpcb *tp, struct tcp_rack *rack, uint32_t cts, tcp_seq snd_una) { struct timeval tv; if (rack->rc_in_persist == 0) { if (tp->t_flags & TF_GPUTINPROG) { /* * Stop the goodput now, the calling of the * measurement function clears the flag. */ rack_do_goodput_measurement(tp, rack, tp->snd_una, __LINE__, RACK_QUALITY_PERSIST); } #ifdef NETFLIX_SHARED_CWND if (rack->r_ctl.rc_scw) { tcp_shared_cwnd_idle(rack->r_ctl.rc_scw, rack->r_ctl.rc_scw_index); rack->rack_scwnd_is_idle = 1; } #endif rack->r_ctl.rc_went_idle_time = tcp_get_usecs(&tv); if (rack->lt_bw_up) { /* Suspend our LT BW measurement */ uint64_t tmark; rack->r_ctl.lt_bw_bytes += (snd_una - rack->r_ctl.lt_seq); rack->r_ctl.lt_seq = snd_una; tmark = tcp_tv_to_lusectick(&tv); rack->r_ctl.lt_bw_time += (tmark - rack->r_ctl.lt_timemark); rack->r_ctl.lt_timemark = tmark; rack->lt_bw_up = 0; rack->r_persist_lt_bw_off = 1; } if (rack->r_ctl.rc_went_idle_time == 0) rack->r_ctl.rc_went_idle_time = 1; rack_timer_cancel(tp, rack, cts, __LINE__); rack->r_ctl.persist_lost_ends = 0; rack->probe_not_answered = 0; rack->forced_ack = 0; tp->t_rxtshift = 0; RACK_TCPT_RANGESET(tp->t_rxtcur, RACK_REXMTVAL(tp), rack_rto_min, rack_rto_max, rack->r_ctl.timer_slop); rack->rc_in_persist = 1; } } static void rack_exit_persist(struct tcpcb *tp, struct tcp_rack *rack, uint32_t cts) { struct timeval tv; uint32_t t_time; if (tcp_in_hpts(rack->rc_tp)) { tcp_hpts_remove(rack->rc_tp); rack->r_ctl.rc_hpts_flags = 0; } #ifdef NETFLIX_SHARED_CWND if (rack->r_ctl.rc_scw) { tcp_shared_cwnd_active(rack->r_ctl.rc_scw, rack->r_ctl.rc_scw_index); rack->rack_scwnd_is_idle = 0; } #endif t_time = tcp_get_usecs(&tv); if (rack->rc_gp_dyn_mul && (rack->use_fixed_rate == 0) && (rack->rc_always_pace)) { /* * Do we count this as if a probe-rtt just * finished? */ uint32_t time_idle, idle_min; time_idle = t_time - rack->r_ctl.rc_went_idle_time; idle_min = rack_min_probertt_hold; if (rack_probertt_gpsrtt_cnt_div) { uint64_t extra; extra = (uint64_t)rack->r_ctl.rc_gp_srtt * (uint64_t)rack_probertt_gpsrtt_cnt_mul; extra /= (uint64_t)rack_probertt_gpsrtt_cnt_div; idle_min += (uint32_t)extra; } if (time_idle >= idle_min) { /* Yes, we count it as a probe-rtt. */ uint32_t us_cts; us_cts = tcp_get_usecs(NULL); if (rack->in_probe_rtt == 0) { rack->r_ctl.rc_lower_rtt_us_cts = us_cts; rack->r_ctl.rc_time_probertt_entered = rack->r_ctl.rc_lower_rtt_us_cts; rack->r_ctl.rc_time_probertt_starts = rack->r_ctl.rc_lower_rtt_us_cts; rack->r_ctl.rc_time_of_last_probertt = rack->r_ctl.rc_lower_rtt_us_cts; } else { rack_exit_probertt(rack, us_cts); } } } if (rack->r_persist_lt_bw_off) { /* Continue where we left off */ rack->r_ctl.lt_timemark = tcp_tv_to_lusectick(&tv); rack->lt_bw_up = 1; rack->r_persist_lt_bw_off = 0; } rack->rc_in_persist = 0; rack->r_ctl.rc_went_idle_time = 0; tp->t_rxtshift = 0; RACK_TCPT_RANGESET(tp->t_rxtcur, RACK_REXMTVAL(tp), rack_rto_min, rack_rto_max, rack->r_ctl.timer_slop); rack->r_ctl.rc_agg_delayed = 0; rack->r_early = 0; rack->r_late = 0; rack->r_ctl.rc_agg_early = 0; } static void rack_log_hpts_diag(struct tcp_rack *rack, uint32_t cts, struct hpts_diag *diag, struct timeval *tv) { if (rack_verbose_logging && tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.flex1 = diag->p_nxt_slot; log.u_bbr.flex2 = diag->p_cur_slot; log.u_bbr.flex3 = diag->slot_req; log.u_bbr.flex4 = diag->inp_hptsslot; log.u_bbr.flex5 = diag->slot_remaining; log.u_bbr.flex6 = diag->need_new_to; log.u_bbr.flex7 = diag->p_hpts_active; log.u_bbr.flex8 = diag->p_on_min_sleep; /* Hijack other fields as needed */ log.u_bbr.epoch = diag->have_slept; log.u_bbr.lt_epoch = diag->yet_to_sleep; log.u_bbr.pkts_out = diag->co_ret; log.u_bbr.applimited = diag->hpts_sleep_time; log.u_bbr.delivered = diag->p_prev_slot; log.u_bbr.inflight = diag->p_runningslot; log.u_bbr.bw_inuse = diag->wheel_slot; log.u_bbr.rttProp = diag->wheel_cts; log.u_bbr.timeStamp = cts; log.u_bbr.delRate = diag->maxslots; log.u_bbr.cur_del_rate = diag->p_curtick; log.u_bbr.cur_del_rate <<= 32; log.u_bbr.cur_del_rate |= diag->p_lasttick; TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, BBR_LOG_HPTSDIAG, 0, 0, &log, false, tv); } } static void rack_log_wakeup(struct tcpcb *tp, struct tcp_rack *rack, struct sockbuf *sb, uint32_t len, int type) { if (rack_verbose_logging && tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.flex1 = sb->sb_flags; log.u_bbr.flex2 = len; log.u_bbr.flex3 = sb->sb_state; log.u_bbr.flex8 = type; log.u_bbr.timeStamp = tcp_get_usecs(&tv); TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, TCP_LOG_SB_WAKE, 0, len, &log, false, &tv); } } static void rack_start_hpts_timer(struct tcp_rack *rack, struct tcpcb *tp, uint32_t cts, int32_t slot, uint32_t tot_len_this_send, int sup_rack) { struct hpts_diag diag; struct inpcb *inp = tptoinpcb(tp); struct timeval tv; uint32_t delayed_ack = 0; uint32_t hpts_timeout; uint32_t entry_slot = slot; uint8_t stopped; uint32_t left = 0; uint32_t us_cts; if ((tp->t_state == TCPS_CLOSED) || (tp->t_state == TCPS_LISTEN)) { return; } if (tcp_in_hpts(tp)) { /* Already on the pacer */ return; } stopped = rack->rc_tmr_stopped; if (stopped && TSTMP_GT(rack->r_ctl.rc_timer_exp, cts)) { left = rack->r_ctl.rc_timer_exp - cts; } rack->r_ctl.rc_timer_exp = 0; rack->r_ctl.rc_hpts_flags = 0; us_cts = tcp_get_usecs(&tv); /* Now early/late accounting */ rack_log_pacing_delay_calc(rack, entry_slot, slot, 0, 0, 0, 26, __LINE__, NULL, 0); if (rack->r_early && (rack->rc_ack_can_sendout_data == 0)) { /* * We have a early carry over set, * we can always add more time so we * can always make this compensation. * * Note if ack's are allowed to wake us do not * penalize the next timer for being awoke * by an ack aka the rc_agg_early (non-paced mode). */ slot += rack->r_ctl.rc_agg_early; rack->r_early = 0; rack->r_ctl.rc_agg_early = 0; } if (rack->r_late) { /* * This is harder, we can * compensate some but it * really depends on what * the current pacing time is. */ if (rack->r_ctl.rc_agg_delayed >= slot) { /* * We can't compensate for it all. * And we have to have some time * on the clock. We always have a min * 10 slots (10 x 10 i.e. 100 usecs). */ if (slot <= HPTS_TICKS_PER_SLOT) { /* We gain delay */ rack->r_ctl.rc_agg_delayed += (HPTS_TICKS_PER_SLOT - slot); slot = HPTS_TICKS_PER_SLOT; } else { /* We take off some */ rack->r_ctl.rc_agg_delayed -= (slot - HPTS_TICKS_PER_SLOT); slot = HPTS_TICKS_PER_SLOT; } } else { slot -= rack->r_ctl.rc_agg_delayed; rack->r_ctl.rc_agg_delayed = 0; /* Make sure we have 100 useconds at minimum */ if (slot < HPTS_TICKS_PER_SLOT) { rack->r_ctl.rc_agg_delayed = HPTS_TICKS_PER_SLOT - slot; slot = HPTS_TICKS_PER_SLOT; } if (rack->r_ctl.rc_agg_delayed == 0) rack->r_late = 0; } } hpts_timeout = rack_timer_start(tp, rack, cts, sup_rack); #ifdef TCP_SAD_DETECTION if (rack->sack_attack_disable && (rack->r_ctl.ack_during_sd > 0) && (slot < tcp_sad_pacing_interval)) { /* * We have a potential attacker on * the line. We have possibly some * (or now) pacing time set. We want to * slow down the processing of sacks by some * amount (if it is an attacker). Set the default * slot for attackers in place (unless the original * interval is longer). Its stored in * micro-seconds, so lets convert to msecs. */ slot = tcp_sad_pacing_interval; rack_log_type_bbrsnd(rack, tot_len_this_send, slot, us_cts, &tv, __LINE__); rack->r_ctl.ack_during_sd = 0; } #endif if (tp->t_flags & TF_DELACK) { delayed_ack = TICKS_2_USEC(tcp_delacktime); rack->r_ctl.rc_hpts_flags |= PACE_TMR_DELACK; } if (delayed_ack && ((hpts_timeout == 0) || (delayed_ack < hpts_timeout))) hpts_timeout = delayed_ack; else rack->r_ctl.rc_hpts_flags &= ~PACE_TMR_DELACK; /* * If no timers are going to run and we will fall off the hptsi * wheel, we resort to a keep-alive timer if its configured. */ if ((hpts_timeout == 0) && (slot == 0)) { if ((V_tcp_always_keepalive || inp->inp_socket->so_options & SO_KEEPALIVE) && (tp->t_state <= TCPS_CLOSING)) { /* * Ok we have no timer (persists, rack, tlp, rxt or * del-ack), we don't have segments being paced. So * all that is left is the keepalive timer. */ if (TCPS_HAVEESTABLISHED(tp->t_state)) { /* Get the established keep-alive time */ hpts_timeout = TICKS_2_USEC(TP_KEEPIDLE(tp)); } else { /* * Get the initial setup keep-alive time, * note that this is probably not going to * happen, since rack will be running a rxt timer * if a SYN of some sort is outstanding. It is * actually handled in rack_timeout_rxt(). */ hpts_timeout = TICKS_2_USEC(TP_KEEPINIT(tp)); } rack->r_ctl.rc_hpts_flags |= PACE_TMR_KEEP; if (rack->in_probe_rtt) { /* * We want to instead not wake up a long time from * now but to wake up about the time we would * exit probe-rtt and initiate a keep-alive ack. * This will get us out of probe-rtt and update * our min-rtt. */ hpts_timeout = rack_min_probertt_hold; } } } if (left && (stopped & (PACE_TMR_KEEP | PACE_TMR_DELACK)) == (rack->r_ctl.rc_hpts_flags & PACE_TMR_MASK)) { /* * RACK, TLP, persists and RXT timers all are restartable * based on actions input .. i.e we received a packet (ack * or sack) and that changes things (rw, or snd_una etc). * Thus we can restart them with a new value. For * keep-alive, delayed_ack we keep track of what was left * and restart the timer with a smaller value. */ if (left < hpts_timeout) hpts_timeout = left; } if (hpts_timeout) { /* * Hack alert for now we can't time-out over 2,147,483 * seconds (a bit more than 596 hours), which is probably ok * :). */ if (hpts_timeout > 0x7ffffffe) hpts_timeout = 0x7ffffffe; rack->r_ctl.rc_timer_exp = cts + hpts_timeout; } rack_log_pacing_delay_calc(rack, entry_slot, slot, hpts_timeout, 0, 0, 27, __LINE__, NULL, 0); if ((rack->gp_ready == 0) && (rack->use_fixed_rate == 0) && (hpts_timeout < slot) && (rack->r_ctl.rc_hpts_flags & (PACE_TMR_TLP|PACE_TMR_RXT))) { /* * We have no good estimate yet for the * old clunky burst mitigation or the * real pacing. And the tlp or rxt is smaller * than the pacing calculation. Lets not * pace that long since we know the calculation * so far is not accurate. */ slot = hpts_timeout; } /** * Turn off all the flags for queuing by default. The * flags have important meanings to what happens when * LRO interacts with the transport. Most likely (by default now) * mbuf_queueing and ack compression are on. So the transport * has a couple of flags that control what happens (if those * are not on then these flags won't have any effect since it * won't go through the queuing LRO path). * * TF2_MBUF_QUEUE_READY - This flags says that I am busy * pacing output, so don't disturb. But * it also means LRO can wake me if there * is a SACK arrival. * * TF2_DONT_SACK_QUEUE - This flag is used in conjunction * with the above flag (QUEUE_READY) and * when present it says don't even wake me * if a SACK arrives. * * The idea behind these flags is that if we are pacing we * set the MBUF_QUEUE_READY and only get woken up if * a SACK arrives (which could change things) or if * our pacing timer expires. If, however, we have a rack * timer running, then we don't even want a sack to wake * us since the rack timer has to expire before we can send. * * Other cases should usually have none of the flags set * so LRO can call into us. */ tp->t_flags2 &= ~(TF2_DONT_SACK_QUEUE|TF2_MBUF_QUEUE_READY); if (slot) { rack->r_ctl.rc_hpts_flags |= PACE_PKT_OUTPUT; rack->r_ctl.rc_last_output_to = us_cts + slot; /* * A pacing timer (slot) is being set, in * such a case we cannot send (we are blocked by * the timer). So lets tell LRO that it should not * wake us unless there is a SACK. Note this only * will be effective if mbuf queueing is on or * compressed acks are being processed. */ tp->t_flags2 |= TF2_MBUF_QUEUE_READY; /* * But wait if we have a Rack timer running * even a SACK should not disturb us (with * the exception of r_rr_config 3). */ if ((rack->r_ctl.rc_hpts_flags & PACE_TMR_RACK) || (IN_RECOVERY(tp->t_flags))) { if (rack->r_rr_config != 3) tp->t_flags2 |= TF2_DONT_SACK_QUEUE; else if (rack->rc_pace_dnd) { /* * When DND is on, we only let a sack * interrupt us if we are not in recovery. * * If DND is off, then we never hit here * and let all sacks wake us up. * */ tp->t_flags2 |= TF2_DONT_SACK_QUEUE; } } /* For sack attackers we want to ignore sack */ if (rack->sack_attack_disable == 1) { tp->t_flags2 |= (TF2_DONT_SACK_QUEUE | TF2_MBUF_QUEUE_READY); } else if (rack->rc_ack_can_sendout_data) { /* * Ahh but wait, this is that special case * where the pacing timer can be disturbed * backout the changes (used for non-paced * burst limiting). */ tp->t_flags2 &= ~(TF2_DONT_SACK_QUEUE | TF2_MBUF_QUEUE_READY); } if ((rack->use_rack_rr) && (rack->r_rr_config < 2) && ((hpts_timeout) && (hpts_timeout < slot))) { /* * Arrange for the hpts to kick back in after the * t-o if the t-o does not cause a send. */ (void)tcp_hpts_insert_diag(tp, HPTS_USEC_TO_SLOTS(hpts_timeout), __LINE__, &diag); rack_log_hpts_diag(rack, us_cts, &diag, &tv); rack_log_to_start(rack, cts, hpts_timeout, slot, 0); } else { (void)tcp_hpts_insert_diag(tp, HPTS_USEC_TO_SLOTS(slot), __LINE__, &diag); rack_log_hpts_diag(rack, us_cts, &diag, &tv); rack_log_to_start(rack, cts, hpts_timeout, slot, 1); } } else if (hpts_timeout) { /* * With respect to t_flags2(?) here, lets let any new acks wake * us up here. Since we are not pacing (no pacing timer), output * can happen so we should let it. If its a Rack timer, then any inbound * packet probably won't change the sending (we will be blocked) * but it may change the prr stats so letting it in (the set defaults * at the start of this block) are good enough. */ rack->r_ctl.rc_hpts_flags &= ~PACE_PKT_OUTPUT; (void)tcp_hpts_insert_diag(tp, HPTS_USEC_TO_SLOTS(hpts_timeout), __LINE__, &diag); rack_log_hpts_diag(rack, us_cts, &diag, &tv); rack_log_to_start(rack, cts, hpts_timeout, slot, 0); } else { /* No timer starting */ #ifdef INVARIANTS if (SEQ_GT(tp->snd_max, tp->snd_una)) { panic("tp:%p rack:%p tlts:%d cts:%u slot:%u pto:%u -- no timer started?", tp, rack, tot_len_this_send, cts, slot, hpts_timeout); } #endif } rack->rc_tmr_stopped = 0; if (slot) rack_log_type_bbrsnd(rack, tot_len_this_send, slot, us_cts, &tv, __LINE__); } /* * RACK Timer, here we simply do logging and house keeping. * the normal rack_output() function will call the * appropriate thing to check if we need to do a RACK retransmit. * We return 1, saying don't proceed with rack_output only * when all timers have been stopped (destroyed PCB?). */ static int rack_timeout_rack(struct tcpcb *tp, struct tcp_rack *rack, uint32_t cts) { /* * This timer simply provides an internal trigger to send out data. * The check_recovery_mode call will see if there are needed * retransmissions, if so we will enter fast-recovery. The output * call may or may not do the same thing depending on sysctl * settings. */ struct rack_sendmap *rsm; counter_u64_add(rack_to_tot, 1); if (rack->r_state && (rack->r_state != tp->t_state)) rack_set_state(tp, rack); rack->rc_on_min_to = 0; rsm = rack_check_recovery_mode(tp, cts); rack_log_to_event(rack, RACK_TO_FRM_RACK, rsm); if (rsm) { rack->r_ctl.rc_resend = rsm; rack->r_timer_override = 1; if (rack->use_rack_rr) { /* * Don't accumulate extra pacing delay * we are allowing the rack timer to * over-ride pacing i.e. rrr takes precedence * if the pacing interval is longer than the rrr * time (in other words we get the min pacing * time versus rrr pacing time). */ rack->r_ctl.rc_hpts_flags &= ~PACE_PKT_OUTPUT; } } rack->r_ctl.rc_hpts_flags &= ~PACE_TMR_RACK; if (rsm == NULL) { /* restart a timer and return 1 */ rack_start_hpts_timer(rack, tp, cts, 0, 0, 0); return (1); } return (0); } static void rack_adjust_orig_mlen(struct rack_sendmap *rsm) { if ((M_TRAILINGROOM(rsm->m) != rsm->orig_t_space)) { /* * The trailing space changed, mbufs can grow * at the tail but they can't shrink from * it, KASSERT that. Adjust the orig_m_len to * compensate for this change. */ KASSERT((rsm->orig_t_space > M_TRAILINGROOM(rsm->m)), ("mbuf:%p rsm:%p trailing_space:%jd ots:%u oml:%u mlen:%u\n", rsm->m, rsm, (intmax_t)M_TRAILINGROOM(rsm->m), rsm->orig_t_space, rsm->orig_m_len, rsm->m->m_len)); rsm->orig_m_len += (rsm->orig_t_space - M_TRAILINGROOM(rsm->m)); rsm->orig_t_space = M_TRAILINGROOM(rsm->m); } if (rsm->m->m_len < rsm->orig_m_len) { /* * Mbuf shrank, trimmed off the top by an ack, our * offset changes. */ KASSERT((rsm->soff >= (rsm->orig_m_len - rsm->m->m_len)), ("mbuf:%p len:%u rsm:%p oml:%u soff:%u\n", rsm->m, rsm->m->m_len, rsm, rsm->orig_m_len, rsm->soff)); if (rsm->soff >= (rsm->orig_m_len - rsm->m->m_len)) rsm->soff -= (rsm->orig_m_len - rsm->m->m_len); else rsm->soff = 0; rsm->orig_m_len = rsm->m->m_len; #ifdef INVARIANTS } else if (rsm->m->m_len > rsm->orig_m_len) { panic("rsm:%p m:%p m_len grew outside of t_space compensation", rsm, rsm->m); #endif } } static void rack_setup_offset_for_rsm(struct tcp_rack *rack, struct rack_sendmap *src_rsm, struct rack_sendmap *rsm) { struct mbuf *m; uint32_t soff; if (src_rsm->m && ((src_rsm->orig_m_len != src_rsm->m->m_len) || (M_TRAILINGROOM(src_rsm->m) != src_rsm->orig_t_space))) { /* Fix up the orig_m_len and possibly the mbuf offset */ rack_adjust_orig_mlen(src_rsm); } m = src_rsm->m; soff = src_rsm->soff + (src_rsm->r_end - src_rsm->r_start); while (soff >= m->m_len) { /* Move out past this mbuf */ soff -= m->m_len; m = m->m_next; KASSERT((m != NULL), ("rsm:%p nrsm:%p hit at soff:%u null m", src_rsm, rsm, soff)); if (m == NULL) { /* This should *not* happen which is why there is a kassert */ src_rsm->m = sbsndmbuf(&rack->rc_inp->inp_socket->so_snd, (src_rsm->r_start - rack->rc_tp->snd_una), &src_rsm->soff); src_rsm->orig_m_len = src_rsm->m->m_len; src_rsm->orig_t_space = M_TRAILINGROOM(src_rsm->m); rsm->m = sbsndmbuf(&rack->rc_inp->inp_socket->so_snd, (rsm->r_start - rack->rc_tp->snd_una), &rsm->soff); rsm->orig_m_len = rsm->m->m_len; rsm->orig_t_space = M_TRAILINGROOM(rsm->m); return; } } rsm->m = m; rsm->soff = soff; rsm->orig_m_len = m->m_len; rsm->orig_t_space = M_TRAILINGROOM(rsm->m); } static __inline void rack_clone_rsm(struct tcp_rack *rack, struct rack_sendmap *nrsm, struct rack_sendmap *rsm, uint32_t start) { int idx; nrsm->r_start = start; nrsm->r_end = rsm->r_end; nrsm->r_rtr_cnt = rsm->r_rtr_cnt; nrsm->r_flags = rsm->r_flags; nrsm->r_dupack = rsm->r_dupack; nrsm->r_no_rtt_allowed = rsm->r_no_rtt_allowed; nrsm->r_rtr_bytes = 0; nrsm->r_fas = rsm->r_fas; nrsm->r_bas = rsm->r_bas; rsm->r_end = nrsm->r_start; nrsm->r_just_ret = rsm->r_just_ret; for (idx = 0; idx < nrsm->r_rtr_cnt; idx++) { nrsm->r_tim_lastsent[idx] = rsm->r_tim_lastsent[idx]; } /* Now if we have SYN flag we keep it on the left edge */ if (nrsm->r_flags & RACK_HAS_SYN) nrsm->r_flags &= ~RACK_HAS_SYN; /* Now if we have a FIN flag we keep it on the right edge */ if (rsm->r_flags & RACK_HAS_FIN) rsm->r_flags &= ~RACK_HAS_FIN; /* Push bit must go to the right edge as well */ if (rsm->r_flags & RACK_HAD_PUSH) rsm->r_flags &= ~RACK_HAD_PUSH; /* Clone over the state of the hw_tls flag */ nrsm->r_hw_tls = rsm->r_hw_tls; /* * Now we need to find nrsm's new location in the mbuf chain * we basically calculate a new offset, which is soff + * how much is left in original rsm. Then we walk out the mbuf * chain to find the righ position, it may be the same mbuf * or maybe not. */ KASSERT(((rsm->m != NULL) || (rsm->r_flags & (RACK_HAS_SYN|RACK_HAS_FIN))), ("rsm:%p nrsm:%p rack:%p -- rsm->m is NULL?", rsm, nrsm, rack)); if (rsm->m) rack_setup_offset_for_rsm(rack, rsm, nrsm); } static struct rack_sendmap * rack_merge_rsm(struct tcp_rack *rack, struct rack_sendmap *l_rsm, struct rack_sendmap *r_rsm) { /* * We are merging two ack'd RSM's, * the l_rsm is on the left (lower seq * values) and the r_rsm is on the right * (higher seq value). The simplest way * to merge these is to move the right * one into the left. I don't think there * is any reason we need to try to find * the oldest (or last oldest retransmitted). */ rack_log_map_chg(rack->rc_tp, rack, NULL, l_rsm, r_rsm, MAP_MERGE, r_rsm->r_end, __LINE__); l_rsm->r_end = r_rsm->r_end; if (l_rsm->r_dupack < r_rsm->r_dupack) l_rsm->r_dupack = r_rsm->r_dupack; if (r_rsm->r_rtr_bytes) l_rsm->r_rtr_bytes += r_rsm->r_rtr_bytes; if (r_rsm->r_in_tmap) { /* This really should not happen */ TAILQ_REMOVE(&rack->r_ctl.rc_tmap, r_rsm, r_tnext); r_rsm->r_in_tmap = 0; } /* Now the flags */ if (r_rsm->r_flags & RACK_HAS_FIN) l_rsm->r_flags |= RACK_HAS_FIN; if (r_rsm->r_flags & RACK_TLP) l_rsm->r_flags |= RACK_TLP; if (r_rsm->r_flags & RACK_RWND_COLLAPSED) l_rsm->r_flags |= RACK_RWND_COLLAPSED; if ((r_rsm->r_flags & RACK_APP_LIMITED) && ((l_rsm->r_flags & RACK_APP_LIMITED) == 0)) { /* * If both are app-limited then let the * free lower the count. If right is app * limited and left is not, transfer. */ l_rsm->r_flags |= RACK_APP_LIMITED; r_rsm->r_flags &= ~RACK_APP_LIMITED; if (r_rsm == rack->r_ctl.rc_first_appl) rack->r_ctl.rc_first_appl = l_rsm; } tqhash_remove(rack->r_ctl.tqh, r_rsm, REMOVE_TYPE_MERGE); /* * We keep the largest value, which is the newest * send. We do this in case a segment that is * joined together and not part of a GP estimate * later gets expanded into the GP estimate. * * We prohibit the merging of unlike kinds i.e. * all pieces that are in the GP estimate can be * merged and all pieces that are not in a GP estimate * can be merged, but not disimilar pieces. Combine * this with taking the highest here and we should * be ok unless of course the client reneges. Then * all bets are off. */ if(l_rsm->r_tim_lastsent[(l_rsm->r_rtr_cnt-1)] < r_rsm->r_tim_lastsent[(r_rsm->r_rtr_cnt-1)]) { l_rsm->r_tim_lastsent[(l_rsm->r_rtr_cnt-1)] = r_rsm->r_tim_lastsent[(r_rsm->r_rtr_cnt-1)]; } /* * When merging two RSM's we also need to consider the ack time and keep * newest. If the ack gets merged into a measurement then that is the * one we will want to be using. */ if(l_rsm->r_ack_arrival < r_rsm->r_ack_arrival) l_rsm->r_ack_arrival = r_rsm->r_ack_arrival; if ((r_rsm->r_limit_type == 0) && (l_rsm->r_limit_type != 0)) { /* Transfer the split limit to the map we free */ r_rsm->r_limit_type = l_rsm->r_limit_type; l_rsm->r_limit_type = 0; } rack_free(rack, r_rsm); l_rsm->r_flags |= RACK_MERGED; return (l_rsm); } /* * TLP Timer, here we simply setup what segment we want to * have the TLP expire on, the normal rack_output() will then * send it out. * * We return 1, saying don't proceed with rack_output only * when all timers have been stopped (destroyed PCB?). */ static int rack_timeout_tlp(struct tcpcb *tp, struct tcp_rack *rack, uint32_t cts, uint8_t *doing_tlp) { /* * Tail Loss Probe. */ struct rack_sendmap *rsm = NULL; int insret __diagused; struct socket *so = tptosocket(tp); uint32_t amm; uint32_t out, avail; int collapsed_win = 0; if (TSTMP_LT(cts, rack->r_ctl.rc_timer_exp)) { /* Its not time yet */ return (0); } if (ctf_progress_timeout_check(tp, true)) { rack_log_progress_event(rack, tp, tick, PROGRESS_DROP, __LINE__); return (-ETIMEDOUT); /* tcp_drop() */ } /* * A TLP timer has expired. We have been idle for 2 rtts. So we now * need to figure out how to force a full MSS segment out. */ rack_log_to_event(rack, RACK_TO_FRM_TLP, NULL); rack->r_ctl.retran_during_recovery = 0; rack->r_ctl.dsack_byte_cnt = 0; counter_u64_add(rack_tlp_tot, 1); if (rack->r_state && (rack->r_state != tp->t_state)) rack_set_state(tp, rack); avail = sbavail(&so->so_snd); out = tp->snd_max - tp->snd_una; if ((out > tp->snd_wnd) || rack->rc_has_collapsed) { /* special case, we need a retransmission */ collapsed_win = 1; goto need_retran; } if (rack->r_ctl.dsack_persist && (rack->r_ctl.rc_tlp_cnt_out >= 1)) { rack->r_ctl.dsack_persist--; if (rack->r_ctl.num_dsack && (rack->r_ctl.dsack_persist == 0)) { rack->r_ctl.num_dsack = 0; } rack_log_dsack_event(rack, 1, __LINE__, 0, 0); } if ((tp->t_flags & TF_GPUTINPROG) && (rack->r_ctl.rc_tlp_cnt_out == 1)) { /* * If this is the second in a row * TLP and we are doing a measurement * its time to abandon the measurement. * Something is likely broken on * the clients network and measuring a * broken network does us no good. */ tp->t_flags &= ~TF_GPUTINPROG; rack_log_pacing_delay_calc(rack, (tp->gput_ack - tp->gput_seq) /*flex2*/, rack->r_ctl.rc_gp_srtt /*flex1*/, tp->gput_seq, 0, 0, 18, __LINE__, NULL, 0); } /* * Check our send oldest always settings, and if * there is an oldest to send jump to the need_retran. */ if (rack_always_send_oldest && (TAILQ_EMPTY(&rack->r_ctl.rc_tmap) == 0)) goto need_retran; if (avail > out) { /* New data is available */ amm = avail - out; if (amm > ctf_fixed_maxseg(tp)) { amm = ctf_fixed_maxseg(tp); if ((amm + out) > tp->snd_wnd) { /* We are rwnd limited */ goto need_retran; } } else if (amm < ctf_fixed_maxseg(tp)) { /* not enough to fill a MTU */ goto need_retran; } if (IN_FASTRECOVERY(tp->t_flags)) { /* Unlikely */ if (rack->rack_no_prr == 0) { if (out + amm <= tp->snd_wnd) { rack->r_ctl.rc_prr_sndcnt = amm; rack->r_ctl.rc_tlp_new_data = amm; rack_log_to_prr(rack, 4, 0, __LINE__); } } else goto need_retran; } else { /* Set the send-new override */ if (out + amm <= tp->snd_wnd) rack->r_ctl.rc_tlp_new_data = amm; else goto need_retran; } rack->r_ctl.rc_tlpsend = NULL; counter_u64_add(rack_tlp_newdata, 1); goto send; } need_retran: /* * Ok we need to arrange the last un-acked segment to be re-sent, or * optionally the first un-acked segment. */ if (collapsed_win == 0) { if (rack_always_send_oldest) rsm = TAILQ_FIRST(&rack->r_ctl.rc_tmap); else { rsm = tqhash_max(rack->r_ctl.tqh); if (rsm && (rsm->r_flags & (RACK_ACKED | RACK_HAS_FIN))) { rsm = rack_find_high_nonack(rack, rsm); } } if (rsm == NULL) { #ifdef TCP_BLACKBOX tcp_log_dump_tp_logbuf(tp, "nada counter trips", M_NOWAIT, true); #endif goto out; } } else { /* * We had a collapsed window, lets find * the point before the collapse. */ if (SEQ_GT((rack->r_ctl.last_collapse_point - 1), rack->rc_tp->snd_una)) rsm = tqhash_find(rack->r_ctl.tqh, (rack->r_ctl.last_collapse_point - 1)); else { rsm = tqhash_min(rack->r_ctl.tqh); } if (rsm == NULL) { /* Huh */ goto out; } } if ((rsm->r_end - rsm->r_start) > ctf_fixed_maxseg(tp)) { /* * We need to split this the last segment in two. */ struct rack_sendmap *nrsm; nrsm = rack_alloc_full_limit(rack); if (nrsm == NULL) { /* * No memory to split, we will just exit and punt * off to the RXT timer. */ goto out; } rack_clone_rsm(rack, nrsm, rsm, (rsm->r_end - ctf_fixed_maxseg(tp))); rack_log_map_chg(tp, rack, NULL, rsm, nrsm, MAP_SPLIT, 0, __LINE__); #ifndef INVARIANTS (void)tqhash_insert(rack->r_ctl.tqh, nrsm); #else if ((insret = tqhash_insert(rack->r_ctl.tqh, nrsm)) != 0) { panic("Insert in rb tree of %p fails ret:%d rack:%p rsm:%p", nrsm, insret, rack, rsm); } #endif if (rsm->r_in_tmap) { TAILQ_INSERT_AFTER(&rack->r_ctl.rc_tmap, rsm, nrsm, r_tnext); nrsm->r_in_tmap = 1; } rsm = nrsm; } rack->r_ctl.rc_tlpsend = rsm; send: /* Make sure output path knows we are doing a TLP */ *doing_tlp = 1; rack->r_timer_override = 1; rack->r_ctl.rc_hpts_flags &= ~PACE_TMR_TLP; return (0); out: rack->r_ctl.rc_hpts_flags &= ~PACE_TMR_TLP; return (0); } /* * Delayed ack Timer, here we simply need to setup the * ACK_NOW flag and remove the DELACK flag. From there * the output routine will send the ack out. * * We only return 1, saying don't proceed, if all timers * are stopped (destroyed PCB?). */ static int rack_timeout_delack(struct tcpcb *tp, struct tcp_rack *rack, uint32_t cts) { rack_log_to_event(rack, RACK_TO_FRM_DELACK, NULL); tp->t_flags &= ~TF_DELACK; tp->t_flags |= TF_ACKNOW; KMOD_TCPSTAT_INC(tcps_delack); rack->r_ctl.rc_hpts_flags &= ~PACE_TMR_DELACK; return (0); } /* * Persists timer, here we simply send the * same thing as a keepalive will. * the one byte send. * * We only return 1, saying don't proceed, if all timers * are stopped (destroyed PCB?). */ static int rack_timeout_persist(struct tcpcb *tp, struct tcp_rack *rack, uint32_t cts) { struct tcptemp *t_template; int32_t retval = 1; if (rack->rc_in_persist == 0) return (0); if (ctf_progress_timeout_check(tp, false)) { tcp_log_end_status(tp, TCP_EI_STATUS_PERSIST_MAX); rack_log_progress_event(rack, tp, tick, PROGRESS_DROP, __LINE__); counter_u64_add(rack_persists_lost_ends, rack->r_ctl.persist_lost_ends); return (-ETIMEDOUT); /* tcp_drop() */ } /* * Persistence timer into zero window. Force a byte to be output, if * possible. */ KMOD_TCPSTAT_INC(tcps_persisttimeo); /* * Hack: if the peer is dead/unreachable, we do not time out if the * window is closed. After a full backoff, drop the connection if * the idle time (no responses to probes) reaches the maximum * backoff that we would use if retransmitting. */ if (tp->t_rxtshift >= V_tcp_retries && (ticks - tp->t_rcvtime >= tcp_maxpersistidle || TICKS_2_USEC(ticks - tp->t_rcvtime) >= RACK_REXMTVAL(tp) * tcp_totbackoff)) { KMOD_TCPSTAT_INC(tcps_persistdrop); tcp_log_end_status(tp, TCP_EI_STATUS_PERSIST_MAX); counter_u64_add(rack_persists_lost_ends, rack->r_ctl.persist_lost_ends); retval = -ETIMEDOUT; /* tcp_drop() */ goto out; } if ((sbavail(&rack->rc_inp->inp_socket->so_snd) == 0) && tp->snd_una == tp->snd_max) rack_exit_persist(tp, rack, cts); rack->r_ctl.rc_hpts_flags &= ~PACE_TMR_PERSIT; /* * If the user has closed the socket then drop a persisting * connection after a much reduced timeout. */ if (tp->t_state > TCPS_CLOSE_WAIT && (ticks - tp->t_rcvtime) >= TCPTV_PERSMAX) { KMOD_TCPSTAT_INC(tcps_persistdrop); tcp_log_end_status(tp, TCP_EI_STATUS_PERSIST_MAX); counter_u64_add(rack_persists_lost_ends, rack->r_ctl.persist_lost_ends); retval = -ETIMEDOUT; /* tcp_drop() */ goto out; } t_template = tcpip_maketemplate(rack->rc_inp); if (t_template) { /* only set it if we were answered */ if (rack->forced_ack == 0) { rack->forced_ack = 1; rack->r_ctl.forced_ack_ts = tcp_get_usecs(NULL); } else { rack->probe_not_answered = 1; counter_u64_add(rack_persists_loss, 1); rack->r_ctl.persist_lost_ends++; } counter_u64_add(rack_persists_sends, 1); counter_u64_add(rack_out_size[TCP_MSS_ACCT_PERSIST], 1); tcp_respond(tp, t_template->tt_ipgen, &t_template->tt_t, (struct mbuf *)NULL, tp->rcv_nxt, tp->snd_una - 1, 0); /* This sends an ack */ if (tp->t_flags & TF_DELACK) tp->t_flags &= ~TF_DELACK; free(t_template, M_TEMP); } if (tp->t_rxtshift < V_tcp_retries) tp->t_rxtshift++; out: rack_log_to_event(rack, RACK_TO_FRM_PERSIST, NULL); rack_start_hpts_timer(rack, tp, cts, 0, 0, 0); return (retval); } /* * If a keepalive goes off, we had no other timers * happening. We always return 1 here since this * routine either drops the connection or sends * out a segment with respond. */ static int rack_timeout_keepalive(struct tcpcb *tp, struct tcp_rack *rack, uint32_t cts) { struct tcptemp *t_template; struct inpcb *inp = tptoinpcb(tp); rack->r_ctl.rc_hpts_flags &= ~PACE_TMR_KEEP; rack_log_to_event(rack, RACK_TO_FRM_KEEP, NULL); /* * Keep-alive timer went off; send something or drop connection if * idle for too long. */ KMOD_TCPSTAT_INC(tcps_keeptimeo); if (tp->t_state < TCPS_ESTABLISHED) goto dropit; if ((V_tcp_always_keepalive || inp->inp_socket->so_options & SO_KEEPALIVE) && tp->t_state <= TCPS_CLOSING) { if (ticks - tp->t_rcvtime >= TP_KEEPIDLE(tp) + TP_MAXIDLE(tp)) goto dropit; /* * Send a packet designed to force a response if the peer is * up and reachable: either an ACK if the connection is * still alive, or an RST if the peer has closed the * connection due to timeout or reboot. Using sequence * number tp->snd_una-1 causes the transmitted zero-length * segment to lie outside the receive window; by the * protocol spec, this requires the correspondent TCP to * respond. */ KMOD_TCPSTAT_INC(tcps_keepprobe); t_template = tcpip_maketemplate(inp); if (t_template) { if (rack->forced_ack == 0) { rack->forced_ack = 1; rack->r_ctl.forced_ack_ts = tcp_get_usecs(NULL); } else { rack->probe_not_answered = 1; } tcp_respond(tp, t_template->tt_ipgen, &t_template->tt_t, (struct mbuf *)NULL, tp->rcv_nxt, tp->snd_una - 1, 0); free(t_template, M_TEMP); } } rack_start_hpts_timer(rack, tp, cts, 0, 0, 0); return (1); dropit: KMOD_TCPSTAT_INC(tcps_keepdrops); tcp_log_end_status(tp, TCP_EI_STATUS_KEEP_MAX); return (-ETIMEDOUT); /* tcp_drop() */ } /* * Retransmit helper function, clear up all the ack * flags and take care of important book keeping. */ static void rack_remxt_tmr(struct tcpcb *tp) { /* * The retransmit timer went off, all sack'd blocks must be * un-acked. */ struct rack_sendmap *rsm, *trsm = NULL; struct tcp_rack *rack; rack = (struct tcp_rack *)tp->t_fb_ptr; rack_timer_cancel(tp, rack, tcp_get_usecs(NULL), __LINE__); rack_log_to_event(rack, RACK_TO_FRM_TMR, NULL); if (rack->r_state && (rack->r_state != tp->t_state)) rack_set_state(tp, rack); /* * Ideally we would like to be able to * mark SACK-PASS on anything not acked here. * * However, if we do that we would burst out * all that data 1ms apart. This would be unwise, * so for now we will just let the normal rxt timer * and tlp timer take care of it. * * Also we really need to stick them back in sequence * order. This way we send in the proper order and any * sacks that come floating in will "re-ack" the data. * To do this we zap the tmap with an INIT and then * walk through and place every rsm in the RB tree * back in its seq ordered place. */ TAILQ_INIT(&rack->r_ctl.rc_tmap); TQHASH_FOREACH(rsm, rack->r_ctl.tqh) { rsm->r_dupack = 0; if (rack_verbose_logging) rack_log_retran_reason(rack, rsm, __LINE__, 0, 2); /* We must re-add it back to the tlist */ if (trsm == NULL) { TAILQ_INSERT_HEAD(&rack->r_ctl.rc_tmap, rsm, r_tnext); } else { TAILQ_INSERT_AFTER(&rack->r_ctl.rc_tmap, trsm, rsm, r_tnext); } rsm->r_in_tmap = 1; trsm = rsm; if (rsm->r_flags & RACK_ACKED) rsm->r_flags |= RACK_WAS_ACKED; rsm->r_flags &= ~(RACK_ACKED | RACK_SACK_PASSED | RACK_WAS_SACKPASS | RACK_RWND_COLLAPSED); rsm->r_flags |= RACK_MUST_RXT; } /* Clear the count (we just un-acked them) */ rack->r_ctl.rc_last_timeout_snduna = tp->snd_una; rack->r_ctl.rc_sacked = 0; rack->r_ctl.rc_sacklast = NULL; rack->r_ctl.rc_agg_delayed = 0; rack->r_early = 0; rack->r_ctl.rc_agg_early = 0; rack->r_late = 0; /* Clear the tlp rtx mark */ rack->r_ctl.rc_resend = tqhash_min(rack->r_ctl.tqh); if (rack->r_ctl.rc_resend != NULL) rack->r_ctl.rc_resend->r_flags |= RACK_TO_REXT; rack->r_ctl.rc_prr_sndcnt = 0; rack_log_to_prr(rack, 6, 0, __LINE__); rack->r_timer_override = 1; if ((((tp->t_flags & TF_SACK_PERMIT) == 0) #ifdef TCP_SAD_DETECTION || (rack->sack_attack_disable != 0) #endif ) && ((tp->t_flags & TF_SENTFIN) == 0)) { /* * For non-sack customers new data * needs to go out as retransmits until * we retransmit up to snd_max. */ rack->r_must_retran = 1; rack->r_ctl.rc_out_at_rto = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); } rack->r_ctl.rc_snd_max_at_rto = tp->snd_max; } static void rack_convert_rtts(struct tcpcb *tp) { tcp_change_time_units(tp, TCP_TMR_GRANULARITY_USEC); tp->t_rxtcur = RACK_REXMTVAL(tp); if (TCPS_HAVEESTABLISHED(tp->t_state)) { tp->t_rxtcur += TICKS_2_USEC(tcp_rexmit_slop); } if (tp->t_rxtcur > rack_rto_max) { tp->t_rxtcur = rack_rto_max; } } static void rack_cc_conn_init(struct tcpcb *tp) { struct tcp_rack *rack; uint32_t srtt; rack = (struct tcp_rack *)tp->t_fb_ptr; srtt = tp->t_srtt; cc_conn_init(tp); /* * Now convert to rack's internal format, * if required. */ if ((srtt == 0) && (tp->t_srtt != 0)) rack_convert_rtts(tp); /* * We want a chance to stay in slowstart as * we create a connection. TCP spec says that * initially ssthresh is infinite. For our * purposes that is the snd_wnd. */ if (tp->snd_ssthresh < tp->snd_wnd) { tp->snd_ssthresh = tp->snd_wnd; } /* * We also want to assure a IW worth of * data can get inflight. */ if (rc_init_window(rack) < tp->snd_cwnd) tp->snd_cwnd = rc_init_window(rack); } /* * Re-transmit timeout! If we drop the PCB we will return 1, otherwise * we will setup to retransmit the lowest seq number outstanding. */ static int rack_timeout_rxt(struct tcpcb *tp, struct tcp_rack *rack, uint32_t cts) { struct inpcb *inp = tptoinpcb(tp); int32_t rexmt; int32_t retval = 0; bool isipv6; if ((tp->t_flags & TF_GPUTINPROG) && (tp->t_rxtshift)) { /* * We have had a second timeout * measurements on successive rxt's are not profitable. * It is unlikely to be of any use (the network is * broken or the client went away). */ tp->t_flags &= ~TF_GPUTINPROG; rack_log_pacing_delay_calc(rack, (tp->gput_ack - tp->gput_seq) /*flex2*/, rack->r_ctl.rc_gp_srtt /*flex1*/, tp->gput_seq, 0, 0, 18, __LINE__, NULL, 0); } if (ctf_progress_timeout_check(tp, false)) { tcp_log_end_status(tp, TCP_EI_STATUS_RETRAN); rack_log_progress_event(rack, tp, tick, PROGRESS_DROP, __LINE__); return (-ETIMEDOUT); /* tcp_drop() */ } rack->r_ctl.rc_hpts_flags &= ~PACE_TMR_RXT; rack->r_ctl.retran_during_recovery = 0; rack->rc_ack_required = 1; rack->r_ctl.dsack_byte_cnt = 0; if (IN_FASTRECOVERY(tp->t_flags)) tp->t_flags |= TF_WASFRECOVERY; else tp->t_flags &= ~TF_WASFRECOVERY; if (IN_CONGRECOVERY(tp->t_flags)) tp->t_flags |= TF_WASCRECOVERY; else tp->t_flags &= ~TF_WASCRECOVERY; if (TCPS_HAVEESTABLISHED(tp->t_state) && (tp->snd_una == tp->snd_max)) { /* Nothing outstanding .. nothing to do */ return (0); } if (rack->r_ctl.dsack_persist) { rack->r_ctl.dsack_persist--; if (rack->r_ctl.num_dsack && (rack->r_ctl.dsack_persist == 0)) { rack->r_ctl.num_dsack = 0; } rack_log_dsack_event(rack, 1, __LINE__, 0, 0); } /* * Rack can only run one timer at a time, so we cannot * run a KEEPINIT (gating SYN sending) and a retransmit * timer for the SYN. So if we are in a front state and * have a KEEPINIT timer we need to check the first transmit * against now to see if we have exceeded the KEEPINIT time * (if one is set). */ if ((TCPS_HAVEESTABLISHED(tp->t_state) == 0) && (TP_KEEPINIT(tp) != 0)) { struct rack_sendmap *rsm; rsm = tqhash_min(rack->r_ctl.tqh); if (rsm) { /* Ok we have something outstanding to test keepinit with */ if ((TSTMP_GT(cts, (uint32_t)rsm->r_tim_lastsent[0])) && ((cts - (uint32_t)rsm->r_tim_lastsent[0]) >= TICKS_2_USEC(TP_KEEPINIT(tp)))) { /* We have exceeded the KEEPINIT time */ tcp_log_end_status(tp, TCP_EI_STATUS_KEEP_MAX); goto drop_it; } } } /* * Retransmission timer went off. Message has not been acked within * retransmit interval. Back off to a longer retransmit interval * and retransmit one segment. */ rack_remxt_tmr(tp); if ((rack->r_ctl.rc_resend == NULL) || ((rack->r_ctl.rc_resend->r_flags & RACK_RWND_COLLAPSED) == 0)) { /* * If the rwnd collapsed on * the one we are retransmitting * it does not count against the * rxt count. */ tp->t_rxtshift++; } if (tp->t_rxtshift > V_tcp_retries) { tcp_log_end_status(tp, TCP_EI_STATUS_RETRAN); drop_it: tp->t_rxtshift = V_tcp_retries; KMOD_TCPSTAT_INC(tcps_timeoutdrop); /* XXXGL: previously t_softerror was casted to uint16_t */ MPASS(tp->t_softerror >= 0); retval = tp->t_softerror ? -tp->t_softerror : -ETIMEDOUT; goto out; /* tcp_drop() */ } if (tp->t_state == TCPS_SYN_SENT) { /* * If the SYN was retransmitted, indicate CWND to be limited * to 1 segment in cc_conn_init(). */ tp->snd_cwnd = 1; } else if (tp->t_rxtshift == 1) { /* * first retransmit; record ssthresh and cwnd so they can be * recovered if this turns out to be a "bad" retransmit. A * retransmit is considered "bad" if an ACK for this segment * is received within RTT/2 interval; the assumption here is * that the ACK was already in flight. See "On Estimating * End-to-End Network Path Properties" by Allman and Paxson * for more details. */ tp->snd_cwnd_prev = tp->snd_cwnd; tp->snd_ssthresh_prev = tp->snd_ssthresh; tp->snd_recover_prev = tp->snd_recover; tp->t_badrxtwin = ticks + (USEC_2_TICKS(tp->t_srtt)/2); tp->t_flags |= TF_PREVVALID; } else if ((tp->t_flags & TF_RCVD_TSTMP) == 0) tp->t_flags &= ~TF_PREVVALID; KMOD_TCPSTAT_INC(tcps_rexmttimeo); if ((tp->t_state == TCPS_SYN_SENT) || (tp->t_state == TCPS_SYN_RECEIVED)) rexmt = RACK_INITIAL_RTO * tcp_backoff[tp->t_rxtshift]; else rexmt = max(rack_rto_min, (tp->t_srtt + (tp->t_rttvar << 2))) * tcp_backoff[tp->t_rxtshift]; RACK_TCPT_RANGESET(tp->t_rxtcur, rexmt, max(rack_rto_min, rexmt), rack_rto_max, rack->r_ctl.timer_slop); /* * We enter the path for PLMTUD if connection is established or, if * connection is FIN_WAIT_1 status, reason for the last is that if * amount of data we send is very small, we could send it in couple * of packets and process straight to FIN. In that case we won't * catch ESTABLISHED state. */ #ifdef INET6 isipv6 = (inp->inp_vflag & INP_IPV6) ? true : false; #else isipv6 = false; #endif if (((V_tcp_pmtud_blackhole_detect == 1) || (V_tcp_pmtud_blackhole_detect == 2 && !isipv6) || (V_tcp_pmtud_blackhole_detect == 3 && isipv6)) && ((tp->t_state == TCPS_ESTABLISHED) || (tp->t_state == TCPS_FIN_WAIT_1))) { /* * Idea here is that at each stage of mtu probe (usually, * 1448 -> 1188 -> 524) should be given 2 chances to recover * before further clamping down. 'tp->t_rxtshift % 2 == 0' * should take care of that. */ if (((tp->t_flags2 & (TF2_PLPMTU_PMTUD | TF2_PLPMTU_MAXSEGSNT)) == (TF2_PLPMTU_PMTUD | TF2_PLPMTU_MAXSEGSNT)) && (tp->t_rxtshift >= 2 && tp->t_rxtshift < 6 && tp->t_rxtshift % 2 == 0)) { /* * Enter Path MTU Black-hole Detection mechanism: - * Disable Path MTU Discovery (IP "DF" bit). - * Reduce MTU to lower value than what we negotiated * with peer. */ if ((tp->t_flags2 & TF2_PLPMTU_BLACKHOLE) == 0) { /* Record that we may have found a black hole. */ tp->t_flags2 |= TF2_PLPMTU_BLACKHOLE; /* Keep track of previous MSS. */ tp->t_pmtud_saved_maxseg = tp->t_maxseg; } /* * Reduce the MSS to blackhole value or to the * default in an attempt to retransmit. */ #ifdef INET6 if (isipv6 && tp->t_maxseg > V_tcp_v6pmtud_blackhole_mss) { /* Use the sysctl tuneable blackhole MSS. */ tp->t_maxseg = V_tcp_v6pmtud_blackhole_mss; KMOD_TCPSTAT_INC(tcps_pmtud_blackhole_activated); } else if (isipv6) { /* Use the default MSS. */ tp->t_maxseg = V_tcp_v6mssdflt; /* * Disable Path MTU Discovery when we switch * to minmss. */ tp->t_flags2 &= ~TF2_PLPMTU_PMTUD; KMOD_TCPSTAT_INC(tcps_pmtud_blackhole_activated_min_mss); } #endif #if defined(INET6) && defined(INET) else #endif #ifdef INET if (tp->t_maxseg > V_tcp_pmtud_blackhole_mss) { /* Use the sysctl tuneable blackhole MSS. */ tp->t_maxseg = V_tcp_pmtud_blackhole_mss; KMOD_TCPSTAT_INC(tcps_pmtud_blackhole_activated); } else { /* Use the default MSS. */ tp->t_maxseg = V_tcp_mssdflt; /* * Disable Path MTU Discovery when we switch * to minmss. */ tp->t_flags2 &= ~TF2_PLPMTU_PMTUD; KMOD_TCPSTAT_INC(tcps_pmtud_blackhole_activated_min_mss); } #endif } else { /* * If further retransmissions are still unsuccessful * with a lowered MTU, maybe this isn't a blackhole * and we restore the previous MSS and blackhole * detection flags. The limit '6' is determined by * giving each probe stage (1448, 1188, 524) 2 * chances to recover. */ if ((tp->t_flags2 & TF2_PLPMTU_BLACKHOLE) && (tp->t_rxtshift >= 6)) { tp->t_flags2 |= TF2_PLPMTU_PMTUD; tp->t_flags2 &= ~TF2_PLPMTU_BLACKHOLE; tp->t_maxseg = tp->t_pmtud_saved_maxseg; KMOD_TCPSTAT_INC(tcps_pmtud_blackhole_failed); } } } /* * Disable RFC1323 and SACK if we haven't got any response to * our third SYN to work-around some broken terminal servers * (most of which have hopefully been retired) that have bad VJ * header compression code which trashes TCP segments containing * unknown-to-them TCP options. */ if (tcp_rexmit_drop_options && (tp->t_state == TCPS_SYN_SENT) && (tp->t_rxtshift == 3)) tp->t_flags &= ~(TF_REQ_SCALE|TF_REQ_TSTMP|TF_SACK_PERMIT); /* * If we backed off this far, our srtt estimate is probably bogus. * Clobber it so we'll take the next rtt measurement as our srtt; * move the current srtt into rttvar to keep the current retransmit * times until then. */ if (tp->t_rxtshift > TCP_MAXRXTSHIFT / 4) { #ifdef INET6 if ((inp->inp_vflag & INP_IPV6) != 0) in6_losing(inp); else #endif in_losing(inp); tp->t_rttvar += tp->t_srtt; tp->t_srtt = 0; } sack_filter_clear(&rack->r_ctl.rack_sf, tp->snd_una); tp->snd_recover = tp->snd_max; tp->t_flags |= TF_ACKNOW; tp->t_rtttime = 0; rack_cong_signal(tp, CC_RTO, tp->snd_una, __LINE__); out: return (retval); } static int rack_process_timers(struct tcpcb *tp, struct tcp_rack *rack, uint32_t cts, uint8_t hpts_calling, uint8_t *doing_tlp) { int32_t ret = 0; int32_t timers = (rack->r_ctl.rc_hpts_flags & PACE_TMR_MASK); if ((tp->t_state >= TCPS_FIN_WAIT_1) && (tp->t_flags & TF_GPUTINPROG)) { /* * We have a goodput in progress * and we have entered a late state. * Do we have enough data in the sb * to handle the GPUT request? */ uint32_t bytes; bytes = tp->gput_ack - tp->gput_seq; if (SEQ_GT(tp->gput_seq, tp->snd_una)) bytes += tp->gput_seq - tp->snd_una; if (bytes > sbavail(&tptosocket(tp)->so_snd)) { /* * There are not enough bytes in the socket * buffer that have been sent to cover this * measurement. Cancel it. */ rack_log_pacing_delay_calc(rack, (tp->gput_ack - tp->gput_seq) /*flex2*/, rack->r_ctl.rc_gp_srtt /*flex1*/, tp->gput_seq, 0, 0, 18, __LINE__, NULL, 0); tp->t_flags &= ~TF_GPUTINPROG; } } if (timers == 0) { return (0); } if (tp->t_state == TCPS_LISTEN) { /* no timers on listen sockets */ if (rack->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) return (0); return (1); } if ((timers & PACE_TMR_RACK) && rack->rc_on_min_to) { /* * For the rack timer when we * are on a min-timeout (which means rrr_conf = 3) * we don't want to check the timer. It may * be going off for a pace and thats ok we * want to send the retransmit (if its ready). * * If its on a normal rack timer (non-min) then * we will check if its expired. */ goto skip_time_check; } if (TSTMP_LT(cts, rack->r_ctl.rc_timer_exp)) { uint32_t left; if (rack->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) { ret = -1; rack_log_to_processing(rack, cts, ret, 0); return (0); } if (hpts_calling == 0) { /* * A user send or queued mbuf (sack) has called us? We * return 0 and let the pacing guards * deal with it if they should or * should not cause a send. */ ret = -2; rack_log_to_processing(rack, cts, ret, 0); return (0); } /* * Ok our timer went off early and we are not paced false * alarm, go back to sleep. We make sure we don't have * no-sack wakeup on since we no longer have a PKT_OUTPUT * flag in place. */ rack->rc_tp->t_flags2 &= ~TF2_DONT_SACK_QUEUE; ret = -3; left = rack->r_ctl.rc_timer_exp - cts; tcp_hpts_insert(tp, HPTS_MS_TO_SLOTS(left)); rack_log_to_processing(rack, cts, ret, left); return (1); } skip_time_check: rack->rc_tmr_stopped = 0; rack->r_ctl.rc_hpts_flags &= ~PACE_TMR_MASK; if (timers & PACE_TMR_DELACK) { ret = rack_timeout_delack(tp, rack, cts); } else if (timers & PACE_TMR_RACK) { rack->r_ctl.rc_tlp_rxt_last_time = cts; rack->r_fast_output = 0; ret = rack_timeout_rack(tp, rack, cts); } else if (timers & PACE_TMR_TLP) { rack->r_ctl.rc_tlp_rxt_last_time = cts; ret = rack_timeout_tlp(tp, rack, cts, doing_tlp); } else if (timers & PACE_TMR_RXT) { rack->r_ctl.rc_tlp_rxt_last_time = cts; rack->r_fast_output = 0; ret = rack_timeout_rxt(tp, rack, cts); } else if (timers & PACE_TMR_PERSIT) { ret = rack_timeout_persist(tp, rack, cts); } else if (timers & PACE_TMR_KEEP) { ret = rack_timeout_keepalive(tp, rack, cts); } rack_log_to_processing(rack, cts, ret, timers); return (ret); } static void rack_timer_cancel(struct tcpcb *tp, struct tcp_rack *rack, uint32_t cts, int line) { struct timeval tv; uint32_t us_cts, flags_on_entry; uint8_t hpts_removed = 0; flags_on_entry = rack->r_ctl.rc_hpts_flags; us_cts = tcp_get_usecs(&tv); if ((rack->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) && ((TSTMP_GEQ(us_cts, rack->r_ctl.rc_last_output_to)) || ((tp->snd_max - tp->snd_una) == 0))) { tcp_hpts_remove(rack->rc_tp); hpts_removed = 1; /* If we were not delayed cancel out the flag. */ if ((tp->snd_max - tp->snd_una) == 0) rack->r_ctl.rc_hpts_flags &= ~PACE_PKT_OUTPUT; rack_log_to_cancel(rack, hpts_removed, line, us_cts, &tv, flags_on_entry); } if (rack->r_ctl.rc_hpts_flags & PACE_TMR_MASK) { rack->rc_tmr_stopped = rack->r_ctl.rc_hpts_flags & PACE_TMR_MASK; if (tcp_in_hpts(rack->rc_tp) && ((rack->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) == 0)) { /* * Canceling timer's when we have no output being * paced. We also must remove ourselves from the * hpts. */ tcp_hpts_remove(rack->rc_tp); hpts_removed = 1; } rack->r_ctl.rc_hpts_flags &= ~(PACE_TMR_MASK); } if (hpts_removed == 0) rack_log_to_cancel(rack, hpts_removed, line, us_cts, &tv, flags_on_entry); } static int rack_stopall(struct tcpcb *tp) { struct tcp_rack *rack; rack = (struct tcp_rack *)tp->t_fb_ptr; rack->t_timers_stopped = 1; return (0); } static void rack_stop_all_timers(struct tcpcb *tp, struct tcp_rack *rack) { /* * Assure no timers are running. */ if (tcp_timer_active(tp, TT_PERSIST)) { /* We enter in persists, set the flag appropriately */ rack->rc_in_persist = 1; } if (tcp_in_hpts(rack->rc_tp)) { tcp_hpts_remove(rack->rc_tp); } } static void rack_update_rsm(struct tcpcb *tp, struct tcp_rack *rack, struct rack_sendmap *rsm, uint64_t ts, uint16_t add_flag, int segsiz) { int32_t idx; rsm->r_rtr_cnt++; rack_log_retran_reason(rack, rsm, __LINE__, 0, 2); rsm->r_dupack = 0; if (rsm->r_rtr_cnt > RACK_NUM_OF_RETRANS) { rsm->r_rtr_cnt = RACK_NUM_OF_RETRANS; rsm->r_flags |= RACK_OVERMAX; } if ((rsm->r_rtr_cnt > 1) && ((rsm->r_flags & RACK_TLP) == 0)) { rack->r_ctl.rc_holes_rxt += (rsm->r_end - rsm->r_start); rsm->r_rtr_bytes += (rsm->r_end - rsm->r_start); } idx = rsm->r_rtr_cnt - 1; rsm->r_tim_lastsent[idx] = ts; /* * Here we don't add in the len of send, since its already * in snduna <->snd_max. */ rsm->r_fas = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); if (rsm->r_flags & RACK_ACKED) { /* Problably MTU discovery messing with us */ rsm->r_flags &= ~RACK_ACKED; rack->r_ctl.rc_sacked -= (rsm->r_end - rsm->r_start); } if (rsm->r_in_tmap) { TAILQ_REMOVE(&rack->r_ctl.rc_tmap, rsm, r_tnext); rsm->r_in_tmap = 0; } /* Lets make sure it really is in or not the GP window */ rack_mark_in_gp_win(tp, rsm); TAILQ_INSERT_TAIL(&rack->r_ctl.rc_tmap, rsm, r_tnext); rsm->r_in_tmap = 1; rsm->r_bas = (uint8_t)(((rsm->r_end - rsm->r_start) + segsiz - 1) / segsiz); /* Take off the must retransmit flag, if its on */ if (rsm->r_flags & RACK_MUST_RXT) { if (rack->r_must_retran) rack->r_ctl.rc_out_at_rto -= (rsm->r_end - rsm->r_start); if (SEQ_GEQ(rsm->r_end, rack->r_ctl.rc_snd_max_at_rto)) { /* * We have retransmitted all we need. Clear * any must retransmit flags. */ rack->r_must_retran = 0; rack->r_ctl.rc_out_at_rto = 0; } rsm->r_flags &= ~RACK_MUST_RXT; } /* Remove any collapsed flag */ rsm->r_flags &= ~RACK_RWND_COLLAPSED; if (rsm->r_flags & RACK_SACK_PASSED) { /* We have retransmitted due to the SACK pass */ rsm->r_flags &= ~RACK_SACK_PASSED; rsm->r_flags |= RACK_WAS_SACKPASS; } } static uint32_t rack_update_entry(struct tcpcb *tp, struct tcp_rack *rack, struct rack_sendmap *rsm, uint64_t ts, int32_t *lenp, uint16_t add_flag, int segsiz) { /* * We (re-)transmitted starting at rsm->r_start for some length * (possibly less than r_end. */ struct rack_sendmap *nrsm; int insret __diagused; uint32_t c_end; int32_t len; len = *lenp; c_end = rsm->r_start + len; if (SEQ_GEQ(c_end, rsm->r_end)) { /* * We retransmitted the whole piece or more than the whole * slopping into the next rsm. */ rack_update_rsm(tp, rack, rsm, ts, add_flag, segsiz); if (c_end == rsm->r_end) { *lenp = 0; return (0); } else { int32_t act_len; /* Hangs over the end return whats left */ act_len = rsm->r_end - rsm->r_start; *lenp = (len - act_len); return (rsm->r_end); } /* We don't get out of this block. */ } /* * Here we retransmitted less than the whole thing which means we * have to split this into what was transmitted and what was not. */ nrsm = rack_alloc_full_limit(rack); if (nrsm == NULL) { /* * We can't get memory, so lets not proceed. */ *lenp = 0; return (0); } /* * So here we are going to take the original rsm and make it what we * retransmitted. nrsm will be the tail portion we did not * retransmit. For example say the chunk was 1, 11 (10 bytes). And * we retransmitted 5 bytes i.e. 1, 5. The original piece shrinks to * 1, 6 and the new piece will be 6, 11. */ rack_clone_rsm(rack, nrsm, rsm, c_end); nrsm->r_dupack = 0; rack_log_retran_reason(rack, nrsm, __LINE__, 0, 2); #ifndef INVARIANTS (void)tqhash_insert(rack->r_ctl.tqh, nrsm); #else if ((insret = tqhash_insert(rack->r_ctl.tqh, nrsm)) != 0) { panic("Insert in rb tree of %p fails ret:%d rack:%p rsm:%p", nrsm, insret, rack, rsm); } #endif if (rsm->r_in_tmap) { TAILQ_INSERT_AFTER(&rack->r_ctl.rc_tmap, rsm, nrsm, r_tnext); nrsm->r_in_tmap = 1; } rsm->r_flags &= (~RACK_HAS_FIN); rack_update_rsm(tp, rack, rsm, ts, add_flag, segsiz); /* Log a split of rsm into rsm and nrsm */ rack_log_map_chg(tp, rack, NULL, rsm, nrsm, MAP_SPLIT, 0, __LINE__); *lenp = 0; return (0); } static void rack_log_output(struct tcpcb *tp, struct tcpopt *to, int32_t len, uint32_t seq_out, uint16_t th_flags, int32_t err, uint64_t cts, struct rack_sendmap *hintrsm, uint16_t add_flag, struct mbuf *s_mb, uint32_t s_moff, int hw_tls, int segsiz) { struct tcp_rack *rack; struct rack_sendmap *rsm, *nrsm; int insret __diagused; register uint32_t snd_max, snd_una; /* * Add to the RACK log of packets in flight or retransmitted. If * there is a TS option we will use the TS echoed, if not we will * grab a TS. * * Retransmissions will increment the count and move the ts to its * proper place. Note that if options do not include TS's then we * won't be able to effectively use the ACK for an RTT on a retran. * * Notes about r_start and r_end. Lets consider a send starting at * sequence 1 for 10 bytes. In such an example the r_start would be * 1 (starting sequence) but the r_end would be r_start+len i.e. 11. * This means that r_end is actually the first sequence for the next * slot (11). * */ /* * If err is set what do we do XXXrrs? should we not add the thing? * -- i.e. return if err != 0 or should we pretend we sent it? -- * i.e. proceed with add ** do this for now. */ INP_WLOCK_ASSERT(tptoinpcb(tp)); if (err) /* * We don't log errors -- we could but snd_max does not * advance in this case either. */ return; if (th_flags & TH_RST) { /* * We don't log resets and we return immediately from * sending */ return; } rack = (struct tcp_rack *)tp->t_fb_ptr; snd_una = tp->snd_una; snd_max = tp->snd_max; if (th_flags & (TH_SYN | TH_FIN)) { /* * The call to rack_log_output is made before bumping * snd_max. This means we can record one extra byte on a SYN * or FIN if seq_out is adding more on and a FIN is present * (and we are not resending). */ if ((th_flags & TH_SYN) && (seq_out == tp->iss)) len++; if (th_flags & TH_FIN) len++; if (SEQ_LT(snd_max, tp->snd_nxt)) { /* * The add/update as not been done for the FIN/SYN * yet. */ snd_max = tp->snd_nxt; } } if (SEQ_LEQ((seq_out + len), snd_una)) { /* Are sending an old segment to induce an ack (keep-alive)? */ return; } if (SEQ_LT(seq_out, snd_una)) { /* huh? should we panic? */ uint32_t end; end = seq_out + len; seq_out = snd_una; if (SEQ_GEQ(end, seq_out)) len = end - seq_out; else len = 0; } if (len == 0) { /* We don't log zero window probes */ return; } if (IN_FASTRECOVERY(tp->t_flags)) { rack->r_ctl.rc_prr_out += len; } /* First question is it a retransmission or new? */ if (seq_out == snd_max) { /* Its new */ rack_chk_req_and_hybrid_on_out(rack, seq_out, len, cts); again: rsm = rack_alloc(rack); if (rsm == NULL) { /* * Hmm out of memory and the tcb got destroyed while * we tried to wait. */ return; } if (th_flags & TH_FIN) { rsm->r_flags = RACK_HAS_FIN|add_flag; } else { rsm->r_flags = add_flag; } if (hw_tls) rsm->r_hw_tls = 1; rsm->r_tim_lastsent[0] = cts; rsm->r_rtr_cnt = 1; rsm->r_rtr_bytes = 0; if (th_flags & TH_SYN) { /* The data space is one beyond snd_una */ rsm->r_flags |= RACK_HAS_SYN; } rsm->r_start = seq_out; rsm->r_end = rsm->r_start + len; rack_mark_in_gp_win(tp, rsm); rsm->r_dupack = 0; /* * save off the mbuf location that * sndmbuf_noadv returned (which is * where we started copying from).. */ rsm->m = s_mb; rsm->soff = s_moff; /* * Here we do add in the len of send, since its not yet * reflected in in snduna <->snd_max */ rsm->r_fas = (ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked) + (rsm->r_end - rsm->r_start)); /* rsm->m will be NULL if RACK_HAS_SYN or RACK_HAS_FIN is set */ if (rsm->m) { if (rsm->m->m_len <= rsm->soff) { /* * XXXrrs Question, will this happen? * * If sbsndptr is set at the correct place * then s_moff should always be somewhere * within rsm->m. But if the sbsndptr was * off then that won't be true. If it occurs * we need to walkout to the correct location. */ struct mbuf *lm; lm = rsm->m; while (lm->m_len <= rsm->soff) { rsm->soff -= lm->m_len; lm = lm->m_next; KASSERT(lm != NULL, ("%s rack:%p lm goes null orig_off:%u origmb:%p rsm->soff:%u", __func__, rack, s_moff, s_mb, rsm->soff)); } rsm->m = lm; } rsm->orig_m_len = rsm->m->m_len; rsm->orig_t_space = M_TRAILINGROOM(rsm->m); } else { rsm->orig_m_len = 0; rsm->orig_t_space = 0; } rsm->r_bas = (uint8_t)((len + segsiz - 1) / segsiz); rack_log_retran_reason(rack, rsm, __LINE__, 0, 2); /* Log a new rsm */ rack_log_map_chg(tp, rack, NULL, rsm, NULL, MAP_NEW, 0, __LINE__); #ifndef INVARIANTS (void)tqhash_insert(rack->r_ctl.tqh, rsm); #else if ((insret = tqhash_insert(rack->r_ctl.tqh, rsm)) != 0) { panic("Insert in rb tree of %p fails ret:%d rack:%p rsm:%p", nrsm, insret, rack, rsm); } #endif TAILQ_INSERT_TAIL(&rack->r_ctl.rc_tmap, rsm, r_tnext); rsm->r_in_tmap = 1; /* * Special case detection, is there just a single * packet outstanding when we are not in recovery? * * If this is true mark it so. */ if ((IN_FASTRECOVERY(tp->t_flags) == 0) && (ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked) == ctf_fixed_maxseg(tp))) { struct rack_sendmap *prsm; prsm = tqhash_prev(rack->r_ctl.tqh, rsm); if (prsm) prsm->r_one_out_nr = 1; } return; } /* * If we reach here its a retransmission and we need to find it. */ more: if (hintrsm && (hintrsm->r_start == seq_out)) { rsm = hintrsm; hintrsm = NULL; } else { /* No hints sorry */ rsm = NULL; } if ((rsm) && (rsm->r_start == seq_out)) { seq_out = rack_update_entry(tp, rack, rsm, cts, &len, add_flag, segsiz); if (len == 0) { return; } else { goto more; } } /* Ok it was not the last pointer go through it the hard way. */ refind: rsm = tqhash_find(rack->r_ctl.tqh, seq_out); if (rsm) { if (rsm->r_start == seq_out) { seq_out = rack_update_entry(tp, rack, rsm, cts, &len, add_flag, segsiz); if (len == 0) { return; } else { goto refind; } } if (SEQ_GEQ(seq_out, rsm->r_start) && SEQ_LT(seq_out, rsm->r_end)) { /* Transmitted within this piece */ /* * Ok we must split off the front and then let the * update do the rest */ nrsm = rack_alloc_full_limit(rack); if (nrsm == NULL) { rack_update_rsm(tp, rack, rsm, cts, add_flag, segsiz); return; } /* * copy rsm to nrsm and then trim the front of rsm * to not include this part. */ rack_clone_rsm(rack, nrsm, rsm, seq_out); rack_log_map_chg(tp, rack, NULL, rsm, nrsm, MAP_SPLIT, 0, __LINE__); #ifndef INVARIANTS (void)tqhash_insert(rack->r_ctl.tqh, nrsm); #else if ((insret = tqhash_insert(rack->r_ctl.tqh, nrsm)) != 0) { panic("Insert in rb tree of %p fails ret:%d rack:%p rsm:%p", nrsm, insret, rack, rsm); } #endif if (rsm->r_in_tmap) { TAILQ_INSERT_AFTER(&rack->r_ctl.rc_tmap, rsm, nrsm, r_tnext); nrsm->r_in_tmap = 1; } rsm->r_flags &= (~RACK_HAS_FIN); seq_out = rack_update_entry(tp, rack, nrsm, cts, &len, add_flag, segsiz); if (len == 0) { return; } else if (len > 0) goto refind; } } /* * Hmm not found in map did they retransmit both old and on into the * new? */ if (seq_out == tp->snd_max) { goto again; } else if (SEQ_LT(seq_out, tp->snd_max)) { #ifdef INVARIANTS printf("seq_out:%u len:%d snd_una:%u snd_max:%u -- but rsm not found?\n", seq_out, len, tp->snd_una, tp->snd_max); printf("Starting Dump of all rack entries\n"); TQHASH_FOREACH(rsm, rack->r_ctl.tqh) { printf("rsm:%p start:%u end:%u\n", rsm, rsm->r_start, rsm->r_end); } printf("Dump complete\n"); panic("seq_out not found rack:%p tp:%p", rack, tp); #endif } else { #ifdef INVARIANTS /* * Hmm beyond sndmax? (only if we are using the new rtt-pack * flag) */ panic("seq_out:%u(%d) is beyond snd_max:%u tp:%p", seq_out, len, tp->snd_max, tp); #endif } } /* * Record one of the RTT updates from an ack into * our sample structure. */ static void tcp_rack_xmit_timer(struct tcp_rack *rack, int32_t rtt, uint32_t len, uint32_t us_rtt, int confidence, struct rack_sendmap *rsm, uint16_t rtrcnt) { if ((rack->r_ctl.rack_rs.rs_flags & RACK_RTT_EMPTY) || (rack->r_ctl.rack_rs.rs_rtt_lowest > rtt)) { rack->r_ctl.rack_rs.rs_rtt_lowest = rtt; } if ((rack->r_ctl.rack_rs.rs_flags & RACK_RTT_EMPTY) || (rack->r_ctl.rack_rs.rs_rtt_highest < rtt)) { rack->r_ctl.rack_rs.rs_rtt_highest = rtt; } if (rack->rc_tp->t_flags & TF_GPUTINPROG) { if (us_rtt < rack->r_ctl.rc_gp_lowrtt) rack->r_ctl.rc_gp_lowrtt = us_rtt; if (rack->rc_tp->snd_wnd > rack->r_ctl.rc_gp_high_rwnd) rack->r_ctl.rc_gp_high_rwnd = rack->rc_tp->snd_wnd; } if ((confidence == 1) && ((rsm == NULL) || (rsm->r_just_ret) || (rsm->r_one_out_nr && len < (ctf_fixed_maxseg(rack->rc_tp) * 2)))) { /* * If the rsm had a just return * hit it then we can't trust the * rtt measurement for buffer deterimination * Note that a confidence of 2, indicates * SACK'd which overrides the r_just_ret or * the r_one_out_nr. If it was a CUM-ACK and * we had only two outstanding, but get an * ack for only 1. Then that also lowers our * confidence. */ confidence = 0; } if ((rack->r_ctl.rack_rs.rs_flags & RACK_RTT_EMPTY) || (rack->r_ctl.rack_rs.rs_us_rtt > us_rtt)) { if (rack->r_ctl.rack_rs.confidence == 0) { /* * We take anything with no current confidence * saved. */ rack->r_ctl.rack_rs.rs_us_rtt = us_rtt; rack->r_ctl.rack_rs.confidence = confidence; rack->r_ctl.rack_rs.rs_us_rtrcnt = rtrcnt; } else if (confidence != 0) { /* * Once we have a confident number, * we can update it with a smaller * value since this confident number * may include the DSACK time until * the next segment (the second one) arrived. */ rack->r_ctl.rack_rs.rs_us_rtt = us_rtt; rack->r_ctl.rack_rs.confidence = confidence; rack->r_ctl.rack_rs.rs_us_rtrcnt = rtrcnt; } } rack_log_rtt_upd(rack->rc_tp, rack, us_rtt, len, rsm, confidence); rack->r_ctl.rack_rs.rs_flags = RACK_RTT_VALID; rack->r_ctl.rack_rs.rs_rtt_tot += rtt; rack->r_ctl.rack_rs.rs_rtt_cnt++; } /* * Collect new round-trip time estimate * and update averages and current timeout. */ static void tcp_rack_xmit_timer_commit(struct tcp_rack *rack, struct tcpcb *tp) { int32_t delta; int32_t rtt; if (rack->r_ctl.rack_rs.rs_flags & RACK_RTT_EMPTY) /* No valid sample */ return; if (rack->r_ctl.rc_rate_sample_method == USE_RTT_LOW) { /* We are to use the lowest RTT seen in a single ack */ rtt = rack->r_ctl.rack_rs.rs_rtt_lowest; } else if (rack->r_ctl.rc_rate_sample_method == USE_RTT_HIGH) { /* We are to use the highest RTT seen in a single ack */ rtt = rack->r_ctl.rack_rs.rs_rtt_highest; } else if (rack->r_ctl.rc_rate_sample_method == USE_RTT_AVG) { /* We are to use the average RTT seen in a single ack */ rtt = (int32_t)(rack->r_ctl.rack_rs.rs_rtt_tot / (uint64_t)rack->r_ctl.rack_rs.rs_rtt_cnt); } else { #ifdef INVARIANTS panic("Unknown rtt variant %d", rack->r_ctl.rc_rate_sample_method); #endif return; } if (rtt == 0) rtt = 1; if (rack->rc_gp_rtt_set == 0) { /* * With no RTT we have to accept * even one we are not confident of. */ rack->r_ctl.rc_gp_srtt = rack->r_ctl.rack_rs.rs_us_rtt; rack->rc_gp_rtt_set = 1; } else if (rack->r_ctl.rack_rs.confidence) { /* update the running gp srtt */ rack->r_ctl.rc_gp_srtt -= (rack->r_ctl.rc_gp_srtt/8); rack->r_ctl.rc_gp_srtt += rack->r_ctl.rack_rs.rs_us_rtt / 8; } if (rack->r_ctl.rack_rs.confidence) { /* * record the low and high for highly buffered path computation, * we only do this if we are confident (not a retransmission). */ if (rack->r_ctl.rc_highest_us_rtt < rack->r_ctl.rack_rs.rs_us_rtt) { rack->r_ctl.rc_highest_us_rtt = rack->r_ctl.rack_rs.rs_us_rtt; } if (rack->rc_highly_buffered == 0) { /* * Currently once we declare a path has * highly buffered there is no going * back, which may be a problem... */ if ((rack->r_ctl.rc_highest_us_rtt / rack->r_ctl.rc_lowest_us_rtt) > rack_hbp_thresh) { rack_log_rtt_shrinks(rack, rack->r_ctl.rack_rs.rs_us_rtt, rack->r_ctl.rc_highest_us_rtt, rack->r_ctl.rc_lowest_us_rtt, RACK_RTTS_SEEHBP); rack->rc_highly_buffered = 1; } } } if ((rack->r_ctl.rack_rs.confidence) || (rack->r_ctl.rack_rs.rs_us_rtrcnt == 1)) { /* * If we are highly confident of it it was * never retransmitted we accept it as the last us_rtt. */ rack->r_ctl.rc_last_us_rtt = rack->r_ctl.rack_rs.rs_us_rtt; /* The lowest rtt can be set if its was not retransmited */ if (rack->r_ctl.rc_lowest_us_rtt > rack->r_ctl.rack_rs.rs_us_rtt) { rack->r_ctl.rc_lowest_us_rtt = rack->r_ctl.rack_rs.rs_us_rtt; if (rack->r_ctl.rc_lowest_us_rtt == 0) rack->r_ctl.rc_lowest_us_rtt = 1; } } rack = (struct tcp_rack *)tp->t_fb_ptr; if (tp->t_srtt != 0) { /* * We keep a simple srtt in microseconds, like our rtt * measurement. We don't need to do any tricks with shifting * etc. Instead we just add in 1/8th of the new measurement * and subtract out 1/8 of the old srtt. We do the same with * the variance after finding the absolute value of the * difference between this sample and the current srtt. */ delta = tp->t_srtt - rtt; /* Take off 1/8th of the current sRTT */ tp->t_srtt -= (tp->t_srtt >> 3); /* Add in 1/8th of the new RTT just measured */ tp->t_srtt += (rtt >> 3); if (tp->t_srtt <= 0) tp->t_srtt = 1; /* Now lets make the absolute value of the variance */ if (delta < 0) delta = -delta; /* Subtract out 1/8th */ tp->t_rttvar -= (tp->t_rttvar >> 3); /* Add in 1/8th of the new variance we just saw */ tp->t_rttvar += (delta >> 3); if (tp->t_rttvar <= 0) tp->t_rttvar = 1; } else { /* * No rtt measurement yet - use the unsmoothed rtt. Set the * variance to half the rtt (so our first retransmit happens * at 3*rtt). */ tp->t_srtt = rtt; tp->t_rttvar = rtt >> 1; } rack->rc_srtt_measure_made = 1; KMOD_TCPSTAT_INC(tcps_rttupdated); if (tp->t_rttupdated < UCHAR_MAX) tp->t_rttupdated++; #ifdef STATS if (rack_stats_gets_ms_rtt == 0) { /* Send in the microsecond rtt used for rxt timeout purposes */ stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_RTT, imax(0, rtt)); } else if (rack_stats_gets_ms_rtt == 1) { /* Send in the millisecond rtt used for rxt timeout purposes */ int32_t ms_rtt; /* Round up */ ms_rtt = (rtt + HPTS_USEC_IN_MSEC - 1) / HPTS_USEC_IN_MSEC; stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_RTT, imax(0, ms_rtt)); } else if (rack_stats_gets_ms_rtt == 2) { /* Send in the millisecond rtt has close to the path RTT as we can get */ int32_t ms_rtt; /* Round up */ ms_rtt = (rack->r_ctl.rack_rs.rs_us_rtt + HPTS_USEC_IN_MSEC - 1) / HPTS_USEC_IN_MSEC; stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_RTT, imax(0, ms_rtt)); } else { /* Send in the microsecond rtt has close to the path RTT as we can get */ stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_RTT, imax(0, rack->r_ctl.rack_rs.rs_us_rtt)); } stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_PATHRTT, imax(0, rack->r_ctl.rack_rs.rs_us_rtt)); #endif /* * the retransmit should happen at rtt + 4 * rttvar. Because of the * way we do the smoothing, srtt and rttvar will each average +1/2 * tick of bias. When we compute the retransmit timer, we want 1/2 * tick of rounding and 1 extra tick because of +-1/2 tick * uncertainty in the firing of the timer. The bias will give us * exactly the 1.5 tick we need. But, because the bias is * statistical, we have to test that we don't drop below the minimum * feasible timer (which is 2 ticks). */ tp->t_rxtshift = 0; RACK_TCPT_RANGESET(tp->t_rxtcur, RACK_REXMTVAL(tp), max(rack_rto_min, rtt + 2), rack_rto_max, rack->r_ctl.timer_slop); rack_log_rtt_sample(rack, rtt); tp->t_softerror = 0; } static void rack_apply_updated_usrtt(struct tcp_rack *rack, uint32_t us_rtt, uint32_t us_cts) { /* * Apply to filter the inbound us-rtt at us_cts. */ uint32_t old_rtt; old_rtt = get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt); apply_filter_min_small(&rack->r_ctl.rc_gp_min_rtt, us_rtt, us_cts); if (old_rtt > us_rtt) { /* We just hit a new lower rtt time */ rack_log_rtt_shrinks(rack, us_cts, old_rtt, __LINE__, RACK_RTTS_NEWRTT); /* * Only count it if its lower than what we saw within our * calculated range. */ if ((old_rtt - us_rtt) > rack_min_rtt_movement) { if (rack_probertt_lower_within && rack->rc_gp_dyn_mul && (rack->use_fixed_rate == 0) && (rack->rc_always_pace)) { /* * We are seeing a new lower rtt very close * to the time that we would have entered probe-rtt. * This is probably due to the fact that a peer flow * has entered probe-rtt. Lets go in now too. */ uint32_t val; val = rack_probertt_lower_within * rack_time_between_probertt; val /= 100; if ((rack->in_probe_rtt == 0) && ((us_cts - rack->r_ctl.rc_lower_rtt_us_cts) >= (rack_time_between_probertt - val))) { rack_enter_probertt(rack, us_cts); } } rack->r_ctl.rc_lower_rtt_us_cts = us_cts; } } } static int rack_update_rtt(struct tcpcb *tp, struct tcp_rack *rack, struct rack_sendmap *rsm, struct tcpopt *to, uint32_t cts, int32_t ack_type, tcp_seq th_ack) { uint32_t us_rtt; int32_t i, all; uint32_t t, len_acked; if ((rsm->r_flags & RACK_ACKED) || (rsm->r_flags & RACK_WAS_ACKED)) /* Already done */ return (0); if (rsm->r_no_rtt_allowed) { /* Not allowed */ return (0); } if (ack_type == CUM_ACKED) { if (SEQ_GT(th_ack, rsm->r_end)) { len_acked = rsm->r_end - rsm->r_start; all = 1; } else { len_acked = th_ack - rsm->r_start; all = 0; } } else { len_acked = rsm->r_end - rsm->r_start; all = 0; } if (rsm->r_rtr_cnt == 1) { t = cts - (uint32_t)rsm->r_tim_lastsent[(rsm->r_rtr_cnt - 1)]; if ((int)t <= 0) t = 1; if (!tp->t_rttlow || tp->t_rttlow > t) tp->t_rttlow = t; if (!rack->r_ctl.rc_rack_min_rtt || SEQ_LT(t, rack->r_ctl.rc_rack_min_rtt)) { rack->r_ctl.rc_rack_min_rtt = t; if (rack->r_ctl.rc_rack_min_rtt == 0) { rack->r_ctl.rc_rack_min_rtt = 1; } } if (TSTMP_GT(tcp_tv_to_usectick(&rack->r_ctl.act_rcv_time), rsm->r_tim_lastsent[(rsm->r_rtr_cnt-1)])) us_rtt = tcp_tv_to_usectick(&rack->r_ctl.act_rcv_time) - (uint32_t)rsm->r_tim_lastsent[(rsm->r_rtr_cnt-1)]; else us_rtt = tcp_get_usecs(NULL) - (uint32_t)rsm->r_tim_lastsent[(rsm->r_rtr_cnt-1)]; if (us_rtt == 0) us_rtt = 1; if (CC_ALGO(tp)->rttsample != NULL) { /* Kick the RTT to the CC */ CC_ALGO(tp)->rttsample(&tp->t_ccv, us_rtt, 1, rsm->r_fas); } rack_apply_updated_usrtt(rack, us_rtt, tcp_tv_to_usectick(&rack->r_ctl.act_rcv_time)); if (ack_type == SACKED) { rack_log_rtt_sample_calc(rack, t, (uint32_t)rsm->r_tim_lastsent[(rsm->r_rtr_cnt - 1)], cts, 1); tcp_rack_xmit_timer(rack, t + 1, len_acked, us_rtt, 2 , rsm, rsm->r_rtr_cnt); } else { /* * We need to setup what our confidence * is in this ack. * * If the rsm was app limited and it is * less than a mss in length (the end * of the send) then we have a gap. If we * were app limited but say we were sending * multiple MSS's then we are more confident * int it. * * When we are not app-limited then we see if * the rsm is being included in the current * measurement, we tell this by the app_limited_needs_set * flag. * * Note that being cwnd blocked is not applimited * as well as the pacing delay between packets which * are sending only 1 or 2 MSS's also will show up * in the RTT. We probably need to examine this algorithm * a bit more and enhance it to account for the delay * between rsm's. We could do that by saving off the * pacing delay of each rsm (in an rsm) and then * factoring that in somehow though for now I am * not sure how :) */ int calc_conf = 0; if (rsm->r_flags & RACK_APP_LIMITED) { if (all && (len_acked <= ctf_fixed_maxseg(tp))) calc_conf = 0; else calc_conf = 1; } else if (rack->app_limited_needs_set == 0) { calc_conf = 1; } else { calc_conf = 0; } rack_log_rtt_sample_calc(rack, t, (uint32_t)rsm->r_tim_lastsent[(rsm->r_rtr_cnt - 1)], cts, 2); tcp_rack_xmit_timer(rack, t + 1, len_acked, us_rtt, calc_conf, rsm, rsm->r_rtr_cnt); } if ((rsm->r_flags & RACK_TLP) && (!IN_FASTRECOVERY(tp->t_flags))) { /* Segment was a TLP and our retrans matched */ if (rack->r_ctl.rc_tlp_cwnd_reduce) { rack_cong_signal(tp, CC_NDUPACK, tp->snd_una, __LINE__); } } if ((rack->r_ctl.rc_rack_tmit_time == 0) || (SEQ_LT(rack->r_ctl.rc_rack_tmit_time, (uint32_t)rsm->r_tim_lastsent[(rsm->r_rtr_cnt - 1)]))) { /* New more recent rack_tmit_time */ rack->r_ctl.rc_rack_tmit_time = (uint32_t)rsm->r_tim_lastsent[(rsm->r_rtr_cnt - 1)]; if (rack->r_ctl.rc_rack_tmit_time == 0) rack->r_ctl.rc_rack_tmit_time = 1; rack->rc_rack_rtt = t; } return (1); } /* * We clear the soft/rxtshift since we got an ack. * There is no assurance we will call the commit() function * so we need to clear these to avoid incorrect handling. */ tp->t_rxtshift = 0; RACK_TCPT_RANGESET(tp->t_rxtcur, RACK_REXMTVAL(tp), rack_rto_min, rack_rto_max, rack->r_ctl.timer_slop); tp->t_softerror = 0; if (to && (to->to_flags & TOF_TS) && (ack_type == CUM_ACKED) && (to->to_tsecr) && ((rsm->r_flags & RACK_OVERMAX) == 0)) { /* * Now which timestamp does it match? In this block the ACK * must be coming from a previous transmission. */ for (i = 0; i < rsm->r_rtr_cnt; i++) { if (rack_ts_to_msec(rsm->r_tim_lastsent[i]) == to->to_tsecr) { t = cts - (uint32_t)rsm->r_tim_lastsent[i]; if ((int)t <= 0) t = 1; if (CC_ALGO(tp)->rttsample != NULL) { /* * Kick the RTT to the CC, here * we lie a bit in that we know the * retransmission is correct even though * we retransmitted. This is because * we match the timestamps. */ if (TSTMP_GT(tcp_tv_to_usectick(&rack->r_ctl.act_rcv_time), rsm->r_tim_lastsent[i])) us_rtt = tcp_tv_to_usectick(&rack->r_ctl.act_rcv_time) - (uint32_t)rsm->r_tim_lastsent[i]; else us_rtt = tcp_get_usecs(NULL) - (uint32_t)rsm->r_tim_lastsent[i]; CC_ALGO(tp)->rttsample(&tp->t_ccv, us_rtt, 1, rsm->r_fas); } if ((i + 1) < rsm->r_rtr_cnt) { /* * The peer ack'd from our previous * transmission. We have a spurious * retransmission and thus we dont * want to update our rack_rtt. * * Hmm should there be a CC revert here? * */ return (0); } if (!tp->t_rttlow || tp->t_rttlow > t) tp->t_rttlow = t; if (!rack->r_ctl.rc_rack_min_rtt || SEQ_LT(t, rack->r_ctl.rc_rack_min_rtt)) { rack->r_ctl.rc_rack_min_rtt = t; if (rack->r_ctl.rc_rack_min_rtt == 0) { rack->r_ctl.rc_rack_min_rtt = 1; } } if ((rack->r_ctl.rc_rack_tmit_time == 0) || (SEQ_LT(rack->r_ctl.rc_rack_tmit_time, (uint32_t)rsm->r_tim_lastsent[(rsm->r_rtr_cnt - 1)]))) { /* New more recent rack_tmit_time */ rack->r_ctl.rc_rack_tmit_time = (uint32_t)rsm->r_tim_lastsent[(rsm->r_rtr_cnt - 1)]; if (rack->r_ctl.rc_rack_tmit_time == 0) rack->r_ctl.rc_rack_tmit_time = 1; rack->rc_rack_rtt = t; } rack_log_rtt_sample_calc(rack, t, (uint32_t)rsm->r_tim_lastsent[i], cts, 3); tcp_rack_xmit_timer(rack, t + 1, len_acked, t, 0, rsm, rsm->r_rtr_cnt); return (1); } } /* If we are logging log out the sendmap */ if (tcp_bblogging_on(rack->rc_tp)) { for (i = 0; i < rsm->r_rtr_cnt; i++) { rack_log_rtt_sendmap(rack, i, rsm->r_tim_lastsent[i], to->to_tsecr); } } goto ts_not_found; } else { /* * Ok its a SACK block that we retransmitted. or a windows * machine without timestamps. We can tell nothing from the * time-stamp since its not there or the time the peer last * recieved a segment that moved forward its cum-ack point. */ ts_not_found: i = rsm->r_rtr_cnt - 1; t = cts - (uint32_t)rsm->r_tim_lastsent[i]; if ((int)t <= 0) t = 1; if (rack->r_ctl.rc_rack_min_rtt && SEQ_LT(t, rack->r_ctl.rc_rack_min_rtt)) { /* * We retransmitted and the ack came back in less * than the smallest rtt we have observed. We most * likely did an improper retransmit as outlined in * 6.2 Step 2 point 2 in the rack-draft so we * don't want to update our rack_rtt. We in * theory (in future) might want to think about reverting our * cwnd state but we won't for now. */ return (0); } else if (rack->r_ctl.rc_rack_min_rtt) { /* * We retransmitted it and the retransmit did the * job. */ if (!rack->r_ctl.rc_rack_min_rtt || SEQ_LT(t, rack->r_ctl.rc_rack_min_rtt)) { rack->r_ctl.rc_rack_min_rtt = t; if (rack->r_ctl.rc_rack_min_rtt == 0) { rack->r_ctl.rc_rack_min_rtt = 1; } } if ((rack->r_ctl.rc_rack_tmit_time == 0) || (SEQ_LT(rack->r_ctl.rc_rack_tmit_time, (uint32_t)rsm->r_tim_lastsent[i]))) { /* New more recent rack_tmit_time */ rack->r_ctl.rc_rack_tmit_time = (uint32_t)rsm->r_tim_lastsent[i]; if (rack->r_ctl.rc_rack_tmit_time == 0) rack->r_ctl.rc_rack_tmit_time = 1; rack->rc_rack_rtt = t; } return (1); } } return (0); } /* * Mark the SACK_PASSED flag on all entries prior to rsm send wise. */ static void rack_log_sack_passed(struct tcpcb *tp, struct tcp_rack *rack, struct rack_sendmap *rsm) { struct rack_sendmap *nrsm; nrsm = rsm; TAILQ_FOREACH_REVERSE_FROM(nrsm, &rack->r_ctl.rc_tmap, rack_head, r_tnext) { if (nrsm == rsm) { /* Skip original segment he is acked */ continue; } if (nrsm->r_flags & RACK_ACKED) { /* * Skip ack'd segments, though we * should not see these, since tmap * should not have ack'd segments. */ continue; } if (nrsm->r_flags & RACK_RWND_COLLAPSED) { /* * If the peer dropped the rwnd on * these then we don't worry about them. */ continue; } if (nrsm->r_flags & RACK_SACK_PASSED) { /* * We found one that is already marked * passed, we have been here before and * so all others below this are marked. */ break; } nrsm->r_flags |= RACK_SACK_PASSED; nrsm->r_flags &= ~RACK_WAS_SACKPASS; } } static void rack_need_set_test(struct tcpcb *tp, struct tcp_rack *rack, struct rack_sendmap *rsm, tcp_seq th_ack, int line, int use_which) { struct rack_sendmap *s_rsm; if ((tp->t_flags & TF_GPUTINPROG) && SEQ_GEQ(rsm->r_end, tp->gput_seq)) { /* * We were app limited, and this ack * butts up or goes beyond the point where we want * to start our next measurement. We need * to record the new gput_ts as here and * possibly update the start sequence. */ uint32_t seq, ts; if (rsm->r_rtr_cnt > 1) { /* * This is a retransmit, can we * really make any assessment at this * point? We are not really sure of * the timestamp, is it this or the * previous transmission? * * Lets wait for something better that * is not retransmitted. */ return; } seq = tp->gput_seq; ts = tp->gput_ts; rack->app_limited_needs_set = 0; tp->gput_ts = tcp_tv_to_usectick(&rack->r_ctl.act_rcv_time); /* Do we start at a new end? */ if ((use_which == RACK_USE_BEG) && SEQ_GEQ(rsm->r_start, tp->gput_seq)) { /* * When we get an ACK that just eats * up some of the rsm, we set RACK_USE_BEG * since whats at r_start (i.e. th_ack) * is left unacked and thats where the * measurement now starts. */ tp->gput_seq = rsm->r_start; } if ((use_which == RACK_USE_END) && SEQ_GEQ(rsm->r_end, tp->gput_seq)) { /* * We use the end when the cumack * is moving forward and completely * deleting the rsm passed so basically * r_end holds th_ack. * * For SACK's we also want to use the end * since this piece just got sacked and * we want to target anything after that * in our measurement. */ tp->gput_seq = rsm->r_end; } if (use_which == RACK_USE_END_OR_THACK) { /* * special case for ack moving forward, * not a sack, we need to move all the * way up to where this ack cum-ack moves * to. */ if (SEQ_GT(th_ack, rsm->r_end)) tp->gput_seq = th_ack; else tp->gput_seq = rsm->r_end; } if (SEQ_LT(tp->gput_seq, tp->snd_max)) s_rsm = tqhash_find(rack->r_ctl.tqh, tp->gput_seq); else s_rsm = NULL; /* * Pick up the correct send time if we can the rsm passed in * may be equal to s_rsm if the RACK_USE_BEG was set. For the other * two cases (RACK_USE_THACK or RACK_USE_END) most likely we will * find a different seq i.e. the next send up. * * If that has not been sent, s_rsm will be NULL and we must * arrange it so this function will get called again by setting * app_limited_needs_set. */ if (s_rsm) rack->r_ctl.rc_gp_output_ts = s_rsm->r_tim_lastsent[0]; else { /* If we hit here we have to have *not* sent tp->gput_seq */ rack->r_ctl.rc_gp_output_ts = rsm->r_tim_lastsent[0]; /* Set it up so we will go through here again */ rack->app_limited_needs_set = 1; } if (SEQ_GT(tp->gput_seq, tp->gput_ack)) { /* * We moved beyond this guy's range, re-calculate * the new end point. */ if (rack->rc_gp_filled == 0) { tp->gput_ack = tp->gput_seq + max(rc_init_window(rack), (MIN_GP_WIN * ctf_fixed_maxseg(tp))); } else { tp->gput_ack = tp->gput_seq + rack_get_measure_window(tp, rack); } } /* * We are moving the goal post, we may be able to clear the * measure_saw_probe_rtt flag. */ if ((rack->in_probe_rtt == 0) && (rack->measure_saw_probe_rtt) && (SEQ_GEQ(tp->gput_seq, rack->r_ctl.rc_probertt_sndmax_atexit))) rack->measure_saw_probe_rtt = 0; rack_log_pacing_delay_calc(rack, ts, tp->gput_ts, seq, tp->gput_seq, (((uint64_t)rack->r_ctl.rc_app_limited_cnt << 32) | (uint64_t)rack->r_ctl.rc_gp_output_ts), 5, line, NULL, 0); if (rack->rc_gp_filled && ((tp->gput_ack - tp->gput_seq) < max(rc_init_window(rack), (MIN_GP_WIN * ctf_fixed_maxseg(tp))))) { uint32_t ideal_amount; ideal_amount = rack_get_measure_window(tp, rack); if (ideal_amount > sbavail(&tptosocket(tp)->so_snd)) { /* * There is no sense of continuing this measurement * because its too small to gain us anything we * trust. Skip it and that way we can start a new * measurement quicker. */ tp->t_flags &= ~TF_GPUTINPROG; rack_log_pacing_delay_calc(rack, tp->gput_ack, tp->gput_seq, 0, 0, (((uint64_t)rack->r_ctl.rc_app_limited_cnt << 32) | (uint64_t)rack->r_ctl.rc_gp_output_ts), 6, __LINE__, NULL, 0); } else { /* * Reset the window further out. */ tp->gput_ack = tp->gput_seq + ideal_amount; } } rack_tend_gp_marks(tp, rack); rack_log_gpset(rack, tp->gput_ack, 0, 0, line, 2, rsm); } } static inline int is_rsm_inside_declared_tlp_block(struct tcp_rack *rack, struct rack_sendmap *rsm) { if (SEQ_LT(rsm->r_end, rack->r_ctl.last_tlp_acked_start)) { /* Behind our TLP definition or right at */ return (0); } if (SEQ_GT(rsm->r_start, rack->r_ctl.last_tlp_acked_end)) { /* The start is beyond or right at our end of TLP definition */ return (0); } /* It has to be a sub-part of the original TLP recorded */ return (1); } static uint32_t rack_proc_sack_blk(struct tcpcb *tp, struct tcp_rack *rack, struct sackblk *sack, struct tcpopt *to, struct rack_sendmap **prsm, uint32_t cts, int *no_extra, int *moved_two, uint32_t segsiz) { uint32_t start, end, changed = 0; struct rack_sendmap stack_map; struct rack_sendmap *rsm, *nrsm, *prev, *next; int insret __diagused; int32_t used_ref = 1; int moved = 0; #ifdef TCP_SAD_DETECTION int allow_segsiz; int first_time_through = 1; #endif int noextra = 0; int can_use_hookery = 0; start = sack->start; end = sack->end; rsm = *prsm; #ifdef TCP_SAD_DETECTION /* * There are a strange number of proxys and meddle boxes in the world * that seem to cut up segments on different boundaries. This gets us * smaller sacks that are still ok in terms of it being an attacker. * We use the base segsiz to calculate an allowable smallness but * also enforce a min on the segsiz in case it is an attacker playing * games with MSS. So basically if the sack arrives and it is * larger than a worse case 960 bytes, we don't classify the guy * as supicious. */ allow_segsiz = max(segsiz, 1200) * sad_seg_size_per; allow_segsiz /= 1000; #endif do_rest_ofb: if ((rsm == NULL) || (SEQ_LT(end, rsm->r_start)) || (SEQ_GEQ(start, rsm->r_end)) || (SEQ_LT(start, rsm->r_start))) { /* * We are not in the right spot, * find the correct spot in the tree. */ used_ref = 0; rsm = tqhash_find(rack->r_ctl.tqh, start); moved++; } if (rsm == NULL) { /* TSNH */ goto out; } #ifdef TCP_SAD_DETECTION /* Now we must check for suspicous activity */ if ((first_time_through == 1) && ((end - start) < min((rsm->r_end - rsm->r_start), allow_segsiz)) && ((rsm->r_flags & RACK_PMTU_CHG) == 0) && ((rsm->r_flags & RACK_TLP) == 0)) { /* * Its less than a full MSS or the segment being acked * this should only happen if the rsm in question had the * r_just_ret flag set the end matches the end of * the rsm block. * * Note we do not look at segments that have had TLP's on * them since we can get un-reported rwnd collapses that * basically we TLP on and then we get back a sack block * that goes from the start to only a small way. * */ int loss, ok; ok = 0; if (SEQ_GEQ(end, rsm->r_end)) { if (rsm->r_just_ret == 1) { /* This was at the end of a send which is ok */ ok = 1; } else { /* A bit harder was it the end of our segment */ int segs, len; len = (rsm->r_end - rsm->r_start); segs = len / segsiz; segs *= segsiz; if ((segs + (rsm->r_end - start)) == len) { /* * So this last bit was the * end of our send if we cut it * up into segsiz pieces so its ok. */ ok = 1; } } } if (ok == 0) { /* * This guy is doing something suspicious * lets start detection. */ if (rack->rc_suspicious == 0) { tcp_trace_point(rack->rc_tp, TCP_TP_SAD_SUSPECT); counter_u64_add(rack_sack_attacks_suspect, 1); rack->rc_suspicious = 1; rack_log_sad(rack, 4); if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.flex1 = end; log.u_bbr.flex2 = start; log.u_bbr.flex3 = rsm->r_end; log.u_bbr.flex4 = rsm->r_start; log.u_bbr.flex5 = segsiz; log.u_bbr.flex6 = rsm->r_fas; log.u_bbr.flex7 = rsm->r_bas; log.u_bbr.flex8 = 5; log.u_bbr.pkts_out = rsm->r_flags; log.u_bbr.bbr_state = rack->rc_suspicious; log.u_bbr.bbr_substate = rsm->r_just_ret; log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, TCP_SAD_DETECTION, 0, 0, &log, false, &tv); } } /* You loose some ack count every time you sack * a small bit that is not butting to the end of * what we have sent. This is because we never * send small bits unless its the end of the sb. * Anyone sending a sack that is not at the end * is thus very very suspicious. */ loss = (segsiz/2) / (end - start); if (loss < rack->r_ctl.ack_count) rack->r_ctl.ack_count -= loss; else rack->r_ctl.ack_count = 0; } } first_time_through = 0; #endif /* Ok we have an ACK for some piece of this rsm */ if (rsm->r_start != start) { if ((rsm->r_flags & RACK_ACKED) == 0) { /* * Before any splitting or hookery is * done is it a TLP of interest i.e. rxt? */ if ((rsm->r_flags & RACK_TLP) && (rsm->r_rtr_cnt > 1)) { /* * We are splitting a rxt TLP, check * if we need to save off the start/end */ if (rack->rc_last_tlp_acked_set && (is_rsm_inside_declared_tlp_block(rack, rsm))) { /* * We already turned this on since we are inside * the previous one was a partially sack now we * are getting another one (maybe all of it). * */ rack_log_dsack_event(rack, 10, __LINE__, rsm->r_start, rsm->r_end); /* * Lets make sure we have all of it though. */ if (SEQ_LT(rsm->r_start, rack->r_ctl.last_tlp_acked_start)) { rack->r_ctl.last_tlp_acked_start = rsm->r_start; rack_log_dsack_event(rack, 11, __LINE__, rack->r_ctl.last_tlp_acked_start, rack->r_ctl.last_tlp_acked_end); } if (SEQ_GT(rsm->r_end, rack->r_ctl.last_tlp_acked_end)) { rack->r_ctl.last_tlp_acked_end = rsm->r_end; rack_log_dsack_event(rack, 11, __LINE__, rack->r_ctl.last_tlp_acked_start, rack->r_ctl.last_tlp_acked_end); } } else { rack->r_ctl.last_tlp_acked_start = rsm->r_start; rack->r_ctl.last_tlp_acked_end = rsm->r_end; rack->rc_last_tlp_past_cumack = 0; rack->rc_last_tlp_acked_set = 1; rack_log_dsack_event(rack, 8, __LINE__, rsm->r_start, rsm->r_end); } } /** * Need to split this in two pieces the before and after, * the before remains in the map, the after must be * added. In other words we have: * rsm |--------------| * sackblk |-------> * rsm will become * rsm |---| * and nrsm will be the sacked piece * nrsm |----------| * * But before we start down that path lets * see if the sack spans over on top of * the next guy and it is already sacked. * */ /* * Hookery can only be used if the two entries * are in the same bucket and neither one of * them staddle the bucket line. */ next = tqhash_next(rack->r_ctl.tqh, rsm); if (next && (rsm->bindex == next->bindex) && ((rsm->r_flags & RACK_STRADDLE) == 0) && ((next->r_flags & RACK_STRADDLE) == 0) && (rsm->r_flags & RACK_IN_GP_WIN) && (next->r_flags & RACK_IN_GP_WIN)) can_use_hookery = 1; else if (next && (rsm->bindex == next->bindex) && ((rsm->r_flags & RACK_STRADDLE) == 0) && ((next->r_flags & RACK_STRADDLE) == 0) && ((rsm->r_flags & RACK_IN_GP_WIN) == 0) && ((next->r_flags & RACK_IN_GP_WIN) == 0)) can_use_hookery = 1; else can_use_hookery = 0; if (next && can_use_hookery && (next->r_flags & RACK_ACKED) && SEQ_GEQ(end, next->r_start)) { /** * So the next one is already acked, and * we can thus by hookery use our stack_map * to reflect the piece being sacked and * then adjust the two tree entries moving * the start and ends around. So we start like: * rsm |------------| (not-acked) * next |-----------| (acked) * sackblk |--------> * We want to end like so: * rsm |------| (not-acked) * next |-----------------| (acked) * nrsm |-----| * Where nrsm is a temporary stack piece we * use to update all the gizmos. */ /* Copy up our fudge block */ noextra++; nrsm = &stack_map; memcpy(nrsm, rsm, sizeof(struct rack_sendmap)); /* Now adjust our tree blocks */ rsm->r_end = start; next->r_start = start; rsm->r_flags |= RACK_SHUFFLED; next->r_flags |= RACK_SHUFFLED; /* Now we must adjust back where next->m is */ rack_setup_offset_for_rsm(rack, rsm, next); /* * Which timestamp do we keep? It is rather * important in GP measurements to have the * accurate end of the send window. * * We keep the largest value, which is the newest * send. We do this in case a segment that is * joined together and not part of a GP estimate * later gets expanded into the GP estimate. * * We prohibit the merging of unlike kinds i.e. * all pieces that are in the GP estimate can be * merged and all pieces that are not in a GP estimate * can be merged, but not disimilar pieces. Combine * this with taking the highest here and we should * be ok unless of course the client reneges. Then * all bets are off. */ if (next->r_tim_lastsent[(next->r_rtr_cnt-1)] < nrsm->r_tim_lastsent[(nrsm->r_rtr_cnt-1)]) next->r_tim_lastsent[(next->r_rtr_cnt-1)] = nrsm->r_tim_lastsent[(nrsm->r_rtr_cnt-1)]; /* * And we must keep the newest ack arrival time. */ if (next->r_ack_arrival < rack_to_usec_ts(&rack->r_ctl.act_rcv_time)) next->r_ack_arrival = rack_to_usec_ts(&rack->r_ctl.act_rcv_time); /* We don't need to adjust rsm, it did not change */ /* Clear out the dup ack count of the remainder */ rsm->r_dupack = 0; rsm->r_just_ret = 0; rack_log_retran_reason(rack, rsm, __LINE__, 0, 2); /* Now lets make sure our fudge block is right */ nrsm->r_start = start; /* Now lets update all the stats and such */ rack_update_rtt(tp, rack, nrsm, to, cts, SACKED, 0); if (rack->app_limited_needs_set) rack_need_set_test(tp, rack, nrsm, tp->snd_una, __LINE__, RACK_USE_END); changed += (nrsm->r_end - nrsm->r_start); /* You get a count for acking a whole segment or more */ if ((nrsm->r_end - nrsm->r_start) >= segsiz) rack->r_ctl.ack_count += ((nrsm->r_end - nrsm->r_start) / segsiz); rack->r_ctl.rc_sacked += (nrsm->r_end - nrsm->r_start); if (nrsm->r_flags & RACK_SACK_PASSED) { rack->r_ctl.rc_reorder_ts = cts; if (rack->r_ctl.rc_reorder_ts == 0) rack->r_ctl.rc_reorder_ts = 1; } /* * Now we want to go up from rsm (the * one left un-acked) to the next one * in the tmap. We do this so when * we walk backwards we include marking * sack-passed on rsm (The one passed in * is skipped since it is generally called * on something sacked before removing it * from the tmap). */ if (rsm->r_in_tmap) { nrsm = TAILQ_NEXT(rsm, r_tnext); /* * Now that we have the next * one walk backwards from there. */ if (nrsm && nrsm->r_in_tmap) rack_log_sack_passed(tp, rack, nrsm); } /* Now are we done? */ if (SEQ_LT(end, next->r_end) || (end == next->r_end)) { /* Done with block */ goto out; } rack_log_map_chg(tp, rack, &stack_map, rsm, next, MAP_SACK_M1, end, __LINE__); counter_u64_add(rack_sack_used_next_merge, 1); /* Postion for the next block */ start = next->r_end; rsm = tqhash_next(rack->r_ctl.tqh, next); if (rsm == NULL) goto out; } else { /** * We can't use any hookery here, so we * need to split the map. We enter like * so: * rsm |--------| * sackblk |-----> * We will add the new block nrsm and * that will be the new portion, and then * fall through after reseting rsm. So we * split and look like this: * rsm |----| * sackblk |-----> * nrsm |---| * We then fall through reseting * rsm to nrsm, so the next block * picks it up. */ nrsm = rack_alloc_limit(rack, RACK_LIMIT_TYPE_SPLIT); if (nrsm == NULL) { /* * failed XXXrrs what can we do but loose the sack * info? */ goto out; } counter_u64_add(rack_sack_splits, 1); rack_clone_rsm(rack, nrsm, rsm, start); moved++; rsm->r_just_ret = 0; #ifndef INVARIANTS (void)tqhash_insert(rack->r_ctl.tqh, nrsm); #else if ((insret = tqhash_insert(rack->r_ctl.tqh, nrsm)) != 0) { panic("Insert in rb tree of %p fails ret:%d rack:%p rsm:%p", nrsm, insret, rack, rsm); } #endif if (rsm->r_in_tmap) { TAILQ_INSERT_AFTER(&rack->r_ctl.rc_tmap, rsm, nrsm, r_tnext); nrsm->r_in_tmap = 1; } rack_log_map_chg(tp, rack, NULL, rsm, nrsm, MAP_SACK_M2, end, __LINE__); rsm->r_flags &= (~RACK_HAS_FIN); /* Position us to point to the new nrsm that starts the sack blk */ rsm = nrsm; } } else { /* Already sacked this piece */ counter_u64_add(rack_sack_skipped_acked, 1); moved++; if (end == rsm->r_end) { /* Done with block */ rsm = tqhash_next(rack->r_ctl.tqh, rsm); goto out; } else if (SEQ_LT(end, rsm->r_end)) { /* A partial sack to a already sacked block */ moved++; rsm = tqhash_next(rack->r_ctl.tqh, rsm); goto out; } else { /* * The end goes beyond this guy * reposition the start to the * next block. */ start = rsm->r_end; rsm = tqhash_next(rack->r_ctl.tqh, rsm); if (rsm == NULL) goto out; } } } if (SEQ_GEQ(end, rsm->r_end)) { /** * The end of this block is either beyond this guy or right * at this guy. I.e.: * rsm --- |-----| * end |-----| * * end |---------| */ if ((rsm->r_flags & RACK_ACKED) == 0) { /* * Is it a TLP of interest? */ if ((rsm->r_flags & RACK_TLP) && (rsm->r_rtr_cnt > 1)) { /* * We are splitting a rxt TLP, check * if we need to save off the start/end */ if (rack->rc_last_tlp_acked_set && (is_rsm_inside_declared_tlp_block(rack, rsm))) { /* * We already turned this on since we are inside * the previous one was a partially sack now we * are getting another one (maybe all of it). */ rack_log_dsack_event(rack, 10, __LINE__, rsm->r_start, rsm->r_end); /* * Lets make sure we have all of it though. */ if (SEQ_LT(rsm->r_start, rack->r_ctl.last_tlp_acked_start)) { rack->r_ctl.last_tlp_acked_start = rsm->r_start; rack_log_dsack_event(rack, 11, __LINE__, rack->r_ctl.last_tlp_acked_start, rack->r_ctl.last_tlp_acked_end); } if (SEQ_GT(rsm->r_end, rack->r_ctl.last_tlp_acked_end)) { rack->r_ctl.last_tlp_acked_end = rsm->r_end; rack_log_dsack_event(rack, 11, __LINE__, rack->r_ctl.last_tlp_acked_start, rack->r_ctl.last_tlp_acked_end); } } else { rack->r_ctl.last_tlp_acked_start = rsm->r_start; rack->r_ctl.last_tlp_acked_end = rsm->r_end; rack->rc_last_tlp_past_cumack = 0; rack->rc_last_tlp_acked_set = 1; rack_log_dsack_event(rack, 8, __LINE__, rsm->r_start, rsm->r_end); } } rack_update_rtt(tp, rack, rsm, to, cts, SACKED, 0); changed += (rsm->r_end - rsm->r_start); /* You get a count for acking a whole segment or more */ if ((rsm->r_end - rsm->r_start) >= segsiz) rack->r_ctl.ack_count += ((rsm->r_end - rsm->r_start) / segsiz); rack->r_ctl.rc_sacked += (rsm->r_end - rsm->r_start); if (rsm->r_in_tmap) /* should be true */ rack_log_sack_passed(tp, rack, rsm); /* Is Reordering occuring? */ if (rsm->r_flags & RACK_SACK_PASSED) { rsm->r_flags &= ~RACK_SACK_PASSED; rack->r_ctl.rc_reorder_ts = cts; if (rack->r_ctl.rc_reorder_ts == 0) rack->r_ctl.rc_reorder_ts = 1; } if (rack->app_limited_needs_set) rack_need_set_test(tp, rack, rsm, tp->snd_una, __LINE__, RACK_USE_END); rsm->r_ack_arrival = rack_to_usec_ts(&rack->r_ctl.act_rcv_time); rsm->r_flags |= RACK_ACKED; if (rsm->r_in_tmap) { TAILQ_REMOVE(&rack->r_ctl.rc_tmap, rsm, r_tnext); rsm->r_in_tmap = 0; } rack_log_map_chg(tp, rack, NULL, rsm, NULL, MAP_SACK_M3, end, __LINE__); } else { counter_u64_add(rack_sack_skipped_acked, 1); moved++; } if (end == rsm->r_end) { /* This block only - done, setup for next */ goto out; } /* * There is more not coverend by this rsm move on * to the next block in the RB tree. */ nrsm = tqhash_next(rack->r_ctl.tqh, rsm); start = rsm->r_end; rsm = nrsm; if (rsm == NULL) goto out; goto do_rest_ofb; } /** * The end of this sack block is smaller than * our rsm i.e.: * rsm --- |-----| * end |--| */ if ((rsm->r_flags & RACK_ACKED) == 0) { /* * Is it a TLP of interest? */ if ((rsm->r_flags & RACK_TLP) && (rsm->r_rtr_cnt > 1)) { /* * We are splitting a rxt TLP, check * if we need to save off the start/end */ if (rack->rc_last_tlp_acked_set && (is_rsm_inside_declared_tlp_block(rack, rsm))) { /* * We already turned this on since we are inside * the previous one was a partially sack now we * are getting another one (maybe all of it). */ rack_log_dsack_event(rack, 10, __LINE__, rsm->r_start, rsm->r_end); /* * Lets make sure we have all of it though. */ if (SEQ_LT(rsm->r_start, rack->r_ctl.last_tlp_acked_start)) { rack->r_ctl.last_tlp_acked_start = rsm->r_start; rack_log_dsack_event(rack, 11, __LINE__, rack->r_ctl.last_tlp_acked_start, rack->r_ctl.last_tlp_acked_end); } if (SEQ_GT(rsm->r_end, rack->r_ctl.last_tlp_acked_end)) { rack->r_ctl.last_tlp_acked_end = rsm->r_end; rack_log_dsack_event(rack, 11, __LINE__, rack->r_ctl.last_tlp_acked_start, rack->r_ctl.last_tlp_acked_end); } } else { rack->r_ctl.last_tlp_acked_start = rsm->r_start; rack->r_ctl.last_tlp_acked_end = rsm->r_end; rack->rc_last_tlp_past_cumack = 0; rack->rc_last_tlp_acked_set = 1; rack_log_dsack_event(rack, 8, __LINE__, rsm->r_start, rsm->r_end); } } /* * Hookery can only be used if the two entries * are in the same bucket and neither one of * them staddle the bucket line. */ prev = tqhash_prev(rack->r_ctl.tqh, rsm); if (prev && (rsm->bindex == prev->bindex) && ((rsm->r_flags & RACK_STRADDLE) == 0) && ((prev->r_flags & RACK_STRADDLE) == 0) && (rsm->r_flags & RACK_IN_GP_WIN) && (prev->r_flags & RACK_IN_GP_WIN)) can_use_hookery = 1; else if (prev && (rsm->bindex == prev->bindex) && ((rsm->r_flags & RACK_STRADDLE) == 0) && ((prev->r_flags & RACK_STRADDLE) == 0) && ((rsm->r_flags & RACK_IN_GP_WIN) == 0) && ((prev->r_flags & RACK_IN_GP_WIN) == 0)) can_use_hookery = 1; else can_use_hookery = 0; if (prev && can_use_hookery && (prev->r_flags & RACK_ACKED)) { /** * Goal, we want the right remainder of rsm to shrink * in place and span from (rsm->r_start = end) to rsm->r_end. * We want to expand prev to go all the way * to prev->r_end <- end. * so in the tree we have before: * prev |--------| (acked) * rsm |-------| (non-acked) * sackblk |-| * We churn it so we end up with * prev |----------| (acked) * rsm |-----| (non-acked) * nrsm |-| (temporary) * * Note if either prev/rsm is a TLP we don't * do this. */ noextra++; nrsm = &stack_map; memcpy(nrsm, rsm, sizeof(struct rack_sendmap)); prev->r_end = end; rsm->r_start = end; rsm->r_flags |= RACK_SHUFFLED; prev->r_flags |= RACK_SHUFFLED; /* Now adjust nrsm (stack copy) to be * the one that is the small * piece that was "sacked". */ nrsm->r_end = end; rsm->r_dupack = 0; /* * Which timestamp do we keep? It is rather * important in GP measurements to have the * accurate end of the send window. * * We keep the largest value, which is the newest * send. We do this in case a segment that is * joined together and not part of a GP estimate * later gets expanded into the GP estimate. * * We prohibit the merging of unlike kinds i.e. * all pieces that are in the GP estimate can be * merged and all pieces that are not in a GP estimate * can be merged, but not disimilar pieces. Combine * this with taking the highest here and we should * be ok unless of course the client reneges. Then * all bets are off. */ if(prev->r_tim_lastsent[(prev->r_rtr_cnt-1)] < nrsm->r_tim_lastsent[(nrsm->r_rtr_cnt-1)]) { prev->r_tim_lastsent[(prev->r_rtr_cnt-1)] = nrsm->r_tim_lastsent[(rsm->r_rtr_cnt-1)]; } /* * And we must keep the newest ack arrival time. */ if(prev->r_ack_arrival < rack_to_usec_ts(&rack->r_ctl.act_rcv_time)) prev->r_ack_arrival = rack_to_usec_ts(&rack->r_ctl.act_rcv_time); rack_log_retran_reason(rack, rsm, __LINE__, 0, 2); /* * Now that the rsm has had its start moved forward * lets go ahead and get its new place in the world. */ rack_setup_offset_for_rsm(rack, prev, rsm); /* * Now nrsm is our new little piece * that is acked (which was merged * to prev). Update the rtt and changed * based on that. Also check for reordering. */ rack_update_rtt(tp, rack, nrsm, to, cts, SACKED, 0); if (rack->app_limited_needs_set) rack_need_set_test(tp, rack, nrsm, tp->snd_una, __LINE__, RACK_USE_END); changed += (nrsm->r_end - nrsm->r_start); /* You get a count for acking a whole segment or more */ if ((nrsm->r_end - nrsm->r_start) >= segsiz) rack->r_ctl.ack_count += ((nrsm->r_end - nrsm->r_start) / segsiz); rack->r_ctl.rc_sacked += (nrsm->r_end - nrsm->r_start); if (nrsm->r_flags & RACK_SACK_PASSED) { rack->r_ctl.rc_reorder_ts = cts; if (rack->r_ctl.rc_reorder_ts == 0) rack->r_ctl.rc_reorder_ts = 1; } rack_log_map_chg(tp, rack, prev, &stack_map, rsm, MAP_SACK_M4, end, __LINE__); rsm = prev; counter_u64_add(rack_sack_used_prev_merge, 1); } else { /** * This is the case where our previous * block is not acked either, so we must * split the block in two. */ nrsm = rack_alloc_limit(rack, RACK_LIMIT_TYPE_SPLIT); if (nrsm == NULL) { /* failed rrs what can we do but loose the sack info? */ goto out; } if ((rsm->r_flags & RACK_TLP) && (rsm->r_rtr_cnt > 1)) { /* * We are splitting a rxt TLP, check * if we need to save off the start/end */ if (rack->rc_last_tlp_acked_set && (is_rsm_inside_declared_tlp_block(rack, rsm))) { /* * We already turned this on since this block is inside * the previous one was a partially sack now we * are getting another one (maybe all of it). */ rack_log_dsack_event(rack, 10, __LINE__, rsm->r_start, rsm->r_end); /* * Lets make sure we have all of it though. */ if (SEQ_LT(rsm->r_start, rack->r_ctl.last_tlp_acked_start)) { rack->r_ctl.last_tlp_acked_start = rsm->r_start; rack_log_dsack_event(rack, 11, __LINE__, rack->r_ctl.last_tlp_acked_start, rack->r_ctl.last_tlp_acked_end); } if (SEQ_GT(rsm->r_end, rack->r_ctl.last_tlp_acked_end)) { rack->r_ctl.last_tlp_acked_end = rsm->r_end; rack_log_dsack_event(rack, 11, __LINE__, rack->r_ctl.last_tlp_acked_start, rack->r_ctl.last_tlp_acked_end); } } else { rack->r_ctl.last_tlp_acked_start = rsm->r_start; rack->r_ctl.last_tlp_acked_end = rsm->r_end; rack->rc_last_tlp_acked_set = 1; rack->rc_last_tlp_past_cumack = 0; rack_log_dsack_event(rack, 8, __LINE__, rsm->r_start, rsm->r_end); } } /** * In this case nrsm becomes * nrsm->r_start = end; * nrsm->r_end = rsm->r_end; * which is un-acked. * * rsm->r_end = nrsm->r_start; * i.e. the remaining un-acked * piece is left on the left * hand side. * * So we start like this * rsm |----------| (not acked) * sackblk |---| * build it so we have * rsm |---| (acked) * nrsm |------| (not acked) */ counter_u64_add(rack_sack_splits, 1); rack_clone_rsm(rack, nrsm, rsm, end); moved++; rsm->r_flags &= (~RACK_HAS_FIN); rsm->r_just_ret = 0; #ifndef INVARIANTS (void)tqhash_insert(rack->r_ctl.tqh, nrsm); #else if ((insret = tqhash_insert(rack->r_ctl.tqh, nrsm)) != 0) { panic("Insert in rb tree of %p fails ret:% rack:%p rsm:%p", nrsm, insret, rack, rsm); } #endif if (rsm->r_in_tmap) { TAILQ_INSERT_AFTER(&rack->r_ctl.rc_tmap, rsm, nrsm, r_tnext); nrsm->r_in_tmap = 1; } nrsm->r_dupack = 0; rack_log_retran_reason(rack, nrsm, __LINE__, 0, 2); rack_update_rtt(tp, rack, rsm, to, cts, SACKED, 0); changed += (rsm->r_end - rsm->r_start); /* You get a count for acking a whole segment or more */ if ((rsm->r_end - rsm->r_start) >= segsiz) rack->r_ctl.ack_count += ((rsm->r_end - rsm->r_start) / segsiz); rack->r_ctl.rc_sacked += (rsm->r_end - rsm->r_start); if (rsm->r_in_tmap) /* should be true */ rack_log_sack_passed(tp, rack, rsm); /* Is Reordering occuring? */ if (rsm->r_flags & RACK_SACK_PASSED) { rsm->r_flags &= ~RACK_SACK_PASSED; rack->r_ctl.rc_reorder_ts = cts; if (rack->r_ctl.rc_reorder_ts == 0) rack->r_ctl.rc_reorder_ts = 1; } if (rack->app_limited_needs_set) rack_need_set_test(tp, rack, rsm, tp->snd_una, __LINE__, RACK_USE_END); rsm->r_ack_arrival = rack_to_usec_ts(&rack->r_ctl.act_rcv_time); rsm->r_flags |= RACK_ACKED; rack_log_map_chg(tp, rack, NULL, rsm, nrsm, MAP_SACK_M5, end, __LINE__); if (rsm->r_in_tmap) { TAILQ_REMOVE(&rack->r_ctl.rc_tmap, rsm, r_tnext); rsm->r_in_tmap = 0; } } } else if (start != end){ /* * The block was already acked. */ counter_u64_add(rack_sack_skipped_acked, 1); moved++; } out: if (rsm && ((rsm->r_flags & RACK_TLP) == 0) && (rsm->r_flags & RACK_ACKED)) { /* * Now can we merge where we worked * with either the previous or * next block? */ next = tqhash_next(rack->r_ctl.tqh, rsm); while (next) { if (next->r_flags & RACK_TLP) break; /* Only allow merges between ones in or out of GP window */ if ((next->r_flags & RACK_IN_GP_WIN) && ((rsm->r_flags & RACK_IN_GP_WIN) == 0)) { break; } if ((rsm->r_flags & RACK_IN_GP_WIN) && ((next->r_flags & RACK_IN_GP_WIN) == 0)) { break; } if (rsm->bindex != next->bindex) break; if (rsm->r_flags & RACK_STRADDLE) break; if (next->r_flags & RACK_STRADDLE) break; if (next->r_flags & RACK_ACKED) { /* yep this and next can be merged */ rsm = rack_merge_rsm(rack, rsm, next); noextra++; next = tqhash_next(rack->r_ctl.tqh, rsm); } else break; } /* Now what about the previous? */ prev = tqhash_prev(rack->r_ctl.tqh, rsm); while (prev) { if (prev->r_flags & RACK_TLP) break; /* Only allow merges between ones in or out of GP window */ if ((prev->r_flags & RACK_IN_GP_WIN) && ((rsm->r_flags & RACK_IN_GP_WIN) == 0)) { break; } if ((rsm->r_flags & RACK_IN_GP_WIN) && ((prev->r_flags & RACK_IN_GP_WIN) == 0)) { break; } if (rsm->bindex != prev->bindex) break; if (rsm->r_flags & RACK_STRADDLE) break; if (prev->r_flags & RACK_STRADDLE) break; if (prev->r_flags & RACK_ACKED) { /* yep the previous and this can be merged */ rsm = rack_merge_rsm(rack, prev, rsm); noextra++; prev = tqhash_prev(rack->r_ctl.tqh, rsm); } else break; } } if (used_ref == 0) { counter_u64_add(rack_sack_proc_all, 1); } else { counter_u64_add(rack_sack_proc_short, 1); } /* Save off the next one for quick reference. */ nrsm = tqhash_find(rack->r_ctl.tqh, end); *prsm = rack->r_ctl.rc_sacklast = nrsm; /* Pass back the moved. */ *moved_two = moved; *no_extra = noextra; return (changed); } static void inline rack_peer_reneges(struct tcp_rack *rack, struct rack_sendmap *rsm, tcp_seq th_ack) { struct rack_sendmap *tmap; tmap = NULL; while (rsm && (rsm->r_flags & RACK_ACKED)) { /* Its no longer sacked, mark it so */ rack->r_ctl.rc_sacked -= (rsm->r_end - rsm->r_start); #ifdef INVARIANTS if (rsm->r_in_tmap) { panic("rack:%p rsm:%p flags:0x%x in tmap?", rack, rsm, rsm->r_flags); } #endif rsm->r_flags &= ~(RACK_ACKED|RACK_SACK_PASSED|RACK_WAS_SACKPASS); /* Rebuild it into our tmap */ if (tmap == NULL) { TAILQ_INSERT_HEAD(&rack->r_ctl.rc_tmap, rsm, r_tnext); tmap = rsm; } else { TAILQ_INSERT_AFTER(&rack->r_ctl.rc_tmap, tmap, rsm, r_tnext); tmap = rsm; } tmap->r_in_tmap = 1; rsm = tqhash_next(rack->r_ctl.tqh, rsm); } /* * Now lets possibly clear the sack filter so we start * recognizing sacks that cover this area. */ sack_filter_clear(&rack->r_ctl.rack_sf, th_ack); } static void rack_do_decay(struct tcp_rack *rack) { struct timeval res; #define timersub(tvp, uvp, vvp) \ do { \ (vvp)->tv_sec = (tvp)->tv_sec - (uvp)->tv_sec; \ (vvp)->tv_usec = (tvp)->tv_usec - (uvp)->tv_usec; \ if ((vvp)->tv_usec < 0) { \ (vvp)->tv_sec--; \ (vvp)->tv_usec += 1000000; \ } \ } while (0) timersub(&rack->r_ctl.act_rcv_time, &rack->r_ctl.rc_last_time_decay, &res); #undef timersub rack->r_ctl.input_pkt++; if ((rack->rc_in_persist) || (res.tv_sec >= 1) || (rack->rc_tp->snd_max == rack->rc_tp->snd_una)) { /* * Check for decay of non-SAD, * we want all SAD detection metrics to * decay 1/4 per second (or more) passed. * Current default is 800 so it decays * 80% every second. */ #ifdef TCP_SAD_DETECTION uint32_t pkt_delta; pkt_delta = rack->r_ctl.input_pkt - rack->r_ctl.saved_input_pkt; #endif /* Update our saved tracking values */ rack->r_ctl.saved_input_pkt = rack->r_ctl.input_pkt; rack->r_ctl.rc_last_time_decay = rack->r_ctl.act_rcv_time; /* Now do we escape without decay? */ #ifdef TCP_SAD_DETECTION if (rack->rc_in_persist || (rack->rc_tp->snd_max == rack->rc_tp->snd_una) || (pkt_delta < tcp_sad_low_pps)){ /* * We don't decay idle connections * or ones that have a low input pps. */ return; } /* Decay the counters */ rack->r_ctl.ack_count = ctf_decay_count(rack->r_ctl.ack_count, tcp_sad_decay_val); rack->r_ctl.sack_count = ctf_decay_count(rack->r_ctl.sack_count, tcp_sad_decay_val); rack->r_ctl.sack_moved_extra = ctf_decay_count(rack->r_ctl.sack_moved_extra, tcp_sad_decay_val); rack->r_ctl.sack_noextra_move = ctf_decay_count(rack->r_ctl.sack_noextra_move, tcp_sad_decay_val); #endif } } static void inline rack_rsm_sender_update(struct tcp_rack *rack, struct tcpcb *tp, struct rack_sendmap *rsm, uint8_t from) { /* * We look at advancing the end send time for our GP * measurement tracking only as the cumulative acknowledgment * moves forward. You might wonder about this, why not * at every transmission or retransmission within the * GP window update the rc_gp_cumack_ts? Well its rather * nuanced but basically the GP window *may* expand (as * it does below) or worse and harder to track it may shrink. * * This last makes it impossible to track at the time of * the send, since you may set forward your rc_gp_cumack_ts * when you send, because that send *is* in your currently * "guessed" window, but then it shrinks. Now which was * the send time of the last bytes in the window, by the * time you ask that question that part of the sendmap * is freed. So you don't know and you will have too * long of send window. Instead by updating the time * marker only when the cumack advances this assures us * that we will have only the sends in the window of our * GP measurement. * * Another complication from this is the * merging of sendmap entries. During SACK processing this * can happen to conserve the sendmap size. That breaks * everything down in tracking the send window of the GP * estimate. So to prevent that and keep it working with * a tiny bit more limited merging, we only allow like * types to be merged. I.e. if two sends are in the GP window * then its ok to merge them together. If two sends are not * in the GP window its ok to merge them together too. Though * one send in and one send out cannot be merged. We combine * this with never allowing the shrinking of the GP window when * we are in recovery so that we can properly calculate the * sending times. * * This all of course seems complicated, because it is.. :) * * The cum-ack is being advanced upon the sendmap. * If we are not doing a GP estimate don't * proceed. */ uint64_t ts; if ((tp->t_flags & TF_GPUTINPROG) == 0) return; /* * If this sendmap entry is going * beyond the measurement window we had picked, * expand the measurement window by that much. */ if (SEQ_GT(rsm->r_end, tp->gput_ack)) { tp->gput_ack = rsm->r_end; } /* * If we have not setup a ack, then we * have no idea if the newly acked pieces * will be "in our seq measurement range". If * it is when we clear the app_limited_needs_set * flag the timestamp will be updated. */ if (rack->app_limited_needs_set) return; /* * Finally, we grab out the latest timestamp * that this packet was sent and then see * if: * a) The packet touches are newly defined GP range. * b) The time is greater than (newer) than the * one we currently have. If so we update * our sending end time window. * * Note we *do not* do this at send time. The reason * is that if you do you *may* pick up a newer timestamp * for a range you are not going to measure. We project * out how far and then sometimes modify that to be * smaller. If that occurs then you will have a send * that does not belong to the range included. */ if ((ts = rsm->r_tim_lastsent[(rsm->r_rtr_cnt-1)]) <= rack->r_ctl.rc_gp_cumack_ts) return; if (rack_in_gp_window(tp, rsm)) { rack->r_ctl.rc_gp_cumack_ts = ts; rack_log_gpset(rack, tp->gput_ack, (uint32_t)ts, rsm->r_end, __LINE__, from, rsm); } } static void rack_process_to_cumack(struct tcpcb *tp, struct tcp_rack *rack, register uint32_t th_ack, uint32_t cts, struct tcpopt *to, uint64_t acktime) { struct rack_sendmap *rsm; /* * The ACK point is advancing to th_ack, we must drop off * the packets in the rack log and calculate any eligble * RTT's. */ rack->r_wanted_output = 1; if (SEQ_GT(th_ack, tp->snd_una)) rack->r_ctl.last_cumack_advance = acktime; /* Tend any TLP that has been marked for 1/2 the seq space (its old) */ if ((rack->rc_last_tlp_acked_set == 1)&& (rack->rc_last_tlp_past_cumack == 1) && (SEQ_GT(rack->r_ctl.last_tlp_acked_start, th_ack))) { /* * We have reached the point where our last rack * tlp retransmit sequence is ahead of the cum-ack. * This can only happen when the cum-ack moves all * the way around (its been a full 2^^31+1 bytes * or more since we sent a retransmitted TLP). Lets * turn off the valid flag since its not really valid. * * Note since sack's also turn on this event we have * a complication, we have to wait to age it out until * the cum-ack is by the TLP before checking which is * what the next else clause does. */ rack_log_dsack_event(rack, 9, __LINE__, rack->r_ctl.last_tlp_acked_start, rack->r_ctl.last_tlp_acked_end); rack->rc_last_tlp_acked_set = 0; rack->rc_last_tlp_past_cumack = 0; } else if ((rack->rc_last_tlp_acked_set == 1) && (rack->rc_last_tlp_past_cumack == 0) && (SEQ_GEQ(th_ack, rack->r_ctl.last_tlp_acked_end))) { /* * It is safe to start aging TLP's out. */ rack->rc_last_tlp_past_cumack = 1; } /* We do the same for the tlp send seq as well */ if ((rack->rc_last_sent_tlp_seq_valid == 1) && (rack->rc_last_sent_tlp_past_cumack == 1) && (SEQ_GT(rack->r_ctl.last_sent_tlp_seq, th_ack))) { rack_log_dsack_event(rack, 9, __LINE__, rack->r_ctl.last_sent_tlp_seq, (rack->r_ctl.last_sent_tlp_seq + rack->r_ctl.last_sent_tlp_len)); rack->rc_last_sent_tlp_seq_valid = 0; rack->rc_last_sent_tlp_past_cumack = 0; } else if ((rack->rc_last_sent_tlp_seq_valid == 1) && (rack->rc_last_sent_tlp_past_cumack == 0) && (SEQ_GEQ(th_ack, rack->r_ctl.last_sent_tlp_seq))) { /* * It is safe to start aging TLP's send. */ rack->rc_last_sent_tlp_past_cumack = 1; } more: rsm = tqhash_min(rack->r_ctl.tqh); if (rsm == NULL) { if ((th_ack - 1) == tp->iss) { /* * For the SYN incoming case we will not * have called tcp_output for the sending of * the SYN, so there will be no map. All * other cases should probably be a panic. */ return; } if (tp->t_flags & TF_SENTFIN) { /* if we sent a FIN we often will not have map */ return; } #ifdef INVARIANTS panic("No rack map tp:%p for state:%d ack:%u rack:%p snd_una:%u snd_max:%u snd_nxt:%u\n", tp, tp->t_state, th_ack, rack, tp->snd_una, tp->snd_max, tp->snd_nxt); #endif return; } if (SEQ_LT(th_ack, rsm->r_start)) { /* Huh map is missing this */ #ifdef INVARIANTS printf("Rack map starts at r_start:%u for th_ack:%u huh? ts:%d rs:%d\n", rsm->r_start, th_ack, tp->t_state, rack->r_state); #endif return; } rack_update_rtt(tp, rack, rsm, to, cts, CUM_ACKED, th_ack); /* Now was it a retransmitted TLP? */ if ((rsm->r_flags & RACK_TLP) && (rsm->r_rtr_cnt > 1)) { /* * Yes, this rsm was a TLP and retransmitted, remember that * since if a DSACK comes back on this we don't want * to think of it as a reordered segment. This may * get updated again with possibly even other TLPs * in flight, but thats ok. Only when we don't send * a retransmitted TLP for 1/2 the sequences space * will it get turned off (above). */ if (rack->rc_last_tlp_acked_set && (is_rsm_inside_declared_tlp_block(rack, rsm))) { /* * We already turned this on since the end matches, * the previous one was a partially ack now we * are getting another one (maybe all of it). */ rack_log_dsack_event(rack, 10, __LINE__, rsm->r_start, rsm->r_end); /* * Lets make sure we have all of it though. */ if (SEQ_LT(rsm->r_start, rack->r_ctl.last_tlp_acked_start)) { rack->r_ctl.last_tlp_acked_start = rsm->r_start; rack_log_dsack_event(rack, 11, __LINE__, rack->r_ctl.last_tlp_acked_start, rack->r_ctl.last_tlp_acked_end); } if (SEQ_GT(rsm->r_end, rack->r_ctl.last_tlp_acked_end)) { rack->r_ctl.last_tlp_acked_end = rsm->r_end; rack_log_dsack_event(rack, 11, __LINE__, rack->r_ctl.last_tlp_acked_start, rack->r_ctl.last_tlp_acked_end); } } else { rack->rc_last_tlp_past_cumack = 1; rack->r_ctl.last_tlp_acked_start = rsm->r_start; rack->r_ctl.last_tlp_acked_end = rsm->r_end; rack->rc_last_tlp_acked_set = 1; rack_log_dsack_event(rack, 8, __LINE__, rsm->r_start, rsm->r_end); } } /* Now do we consume the whole thing? */ rack->r_ctl.last_tmit_time_acked = rsm->r_tim_lastsent[(rsm->r_rtr_cnt - 1)]; if (SEQ_GEQ(th_ack, rsm->r_end)) { /* Its all consumed. */ uint32_t left; uint8_t newly_acked; rack_log_map_chg(tp, rack, NULL, rsm, NULL, MAP_FREE, rsm->r_end, __LINE__); rack->r_ctl.rc_holes_rxt -= rsm->r_rtr_bytes; rsm->r_rtr_bytes = 0; /* * Record the time of highest cumack sent if its in our measurement * window and possibly bump out the end. */ rack_rsm_sender_update(rack, tp, rsm, 4); tqhash_remove(rack->r_ctl.tqh, rsm, REMOVE_TYPE_CUMACK); if (rsm->r_in_tmap) { TAILQ_REMOVE(&rack->r_ctl.rc_tmap, rsm, r_tnext); rsm->r_in_tmap = 0; } newly_acked = 1; if (rsm->r_flags & RACK_ACKED) { /* * It was acked on the scoreboard -- remove * it from total */ rack->r_ctl.rc_sacked -= (rsm->r_end - rsm->r_start); newly_acked = 0; } else if (rsm->r_flags & RACK_SACK_PASSED) { /* * There are segments ACKED on the * scoreboard further up. We are seeing * reordering. */ rsm->r_flags &= ~RACK_SACK_PASSED; rsm->r_ack_arrival = rack_to_usec_ts(&rack->r_ctl.act_rcv_time); rsm->r_flags |= RACK_ACKED; rack->r_ctl.rc_reorder_ts = cts; if (rack->r_ctl.rc_reorder_ts == 0) rack->r_ctl.rc_reorder_ts = 1; if (rack->r_ent_rec_ns) { /* * We have sent no more, and we saw an sack * then ack arrive. */ rack->r_might_revert = 1; } } if ((rsm->r_flags & RACK_TO_REXT) && (tp->t_flags & TF_RCVD_TSTMP) && (to->to_flags & TOF_TS) && (to->to_tsecr != 0) && (tp->t_flags & TF_PREVVALID)) { /* * We can use the timestamp to see * if this retransmission was from the * first transmit. If so we made a mistake. */ tp->t_flags &= ~TF_PREVVALID; if (to->to_tsecr == rack_ts_to_msec(rsm->r_tim_lastsent[0])) { /* The first transmit is what this ack is for */ rack_cong_signal(tp, CC_RTO_ERR, th_ack, __LINE__); } } left = th_ack - rsm->r_end; if (rack->app_limited_needs_set && newly_acked) rack_need_set_test(tp, rack, rsm, th_ack, __LINE__, RACK_USE_END_OR_THACK); /* Free back to zone */ rack_free(rack, rsm); if (left) { goto more; } /* Check for reneging */ rsm = tqhash_min(rack->r_ctl.tqh); if (rsm && (rsm->r_flags & RACK_ACKED) && (th_ack == rsm->r_start)) { /* * The peer has moved snd_una up to * the edge of this send, i.e. one * that it had previously acked. The only * way that can be true if the peer threw * away data (space issues) that it had * previously sacked (else it would have * given us snd_una up to (rsm->r_end). * We need to undo the acked markings here. * * Note we have to look to make sure th_ack is * our rsm->r_start in case we get an old ack * where th_ack is behind snd_una. */ rack_peer_reneges(rack, rsm, th_ack); } return; } if (rsm->r_flags & RACK_ACKED) { /* * It was acked on the scoreboard -- remove it from * total for the part being cum-acked. */ rack->r_ctl.rc_sacked -= (th_ack - rsm->r_start); } /* * Clear the dup ack count for * the piece that remains. */ rsm->r_dupack = 0; rack_log_retran_reason(rack, rsm, __LINE__, 0, 2); if (rsm->r_rtr_bytes) { /* * It was retransmitted adjust the * sack holes for what was acked. */ int ack_am; ack_am = (th_ack - rsm->r_start); if (ack_am >= rsm->r_rtr_bytes) { rack->r_ctl.rc_holes_rxt -= ack_am; rsm->r_rtr_bytes -= ack_am; } } /* * Update where the piece starts and record * the time of send of highest cumack sent if * its in our GP range. */ rack_log_map_chg(tp, rack, NULL, rsm, NULL, MAP_TRIM_HEAD, th_ack, __LINE__); /* Now we need to move our offset forward too */ if (rsm->m && ((rsm->orig_m_len != rsm->m->m_len) || (M_TRAILINGROOM(rsm->m) != rsm->orig_t_space))) { /* Fix up the orig_m_len and possibly the mbuf offset */ rack_adjust_orig_mlen(rsm); } rsm->soff += (th_ack - rsm->r_start); rack_rsm_sender_update(rack, tp, rsm, 5); /* The trim will move th_ack into r_start for us */ tqhash_trim(rack->r_ctl.tqh, th_ack); /* Now do we need to move the mbuf fwd too? */ { struct mbuf *m; uint32_t soff; m = rsm->m; soff = rsm->soff; if (m) { while (soff >= m->m_len) { soff -= m->m_len; KASSERT((m->m_next != NULL), (" rsm:%p off:%u soff:%u m:%p", rsm, rsm->soff, soff, m)); m = m->m_next; if (m == NULL) { /* * This is a fall-back that prevents a panic. In reality * we should be able to walk the mbuf's and find our place. * At this point snd_una has not been updated with the sbcut() yet * but tqhash_trim did update rsm->r_start so the offset calcuation * should work fine. This is undesirable since we will take cache * hits to access the socket buffer. And even more puzzling is that * it happens occasionally. It should not :( */ m = sbsndmbuf(&rack->rc_inp->inp_socket->so_snd, (rsm->r_start - tp->snd_una), &soff); break; } } /* * Now save in our updated values. */ rsm->m = m; rsm->soff = soff; rsm->orig_m_len = rsm->m->m_len; rsm->orig_t_space = M_TRAILINGROOM(rsm->m); } } if (rack->app_limited_needs_set && SEQ_GEQ(th_ack, tp->gput_seq)) rack_need_set_test(tp, rack, rsm, tp->snd_una, __LINE__, RACK_USE_BEG); } static void rack_handle_might_revert(struct tcpcb *tp, struct tcp_rack *rack) { struct rack_sendmap *rsm; int sack_pass_fnd = 0; if (rack->r_might_revert) { /* * Ok we have reordering, have not sent anything, we * might want to revert the congestion state if nothing * further has SACK_PASSED on it. Lets check. * * We also get here when we have DSACKs come in for * all the data that we FR'd. Note that a rxt or tlp * timer clears this from happening. */ TAILQ_FOREACH(rsm, &rack->r_ctl.rc_tmap, r_tnext) { if (rsm->r_flags & RACK_SACK_PASSED) { sack_pass_fnd = 1; break; } } if (sack_pass_fnd == 0) { /* * We went into recovery * incorrectly due to reordering! */ int orig_cwnd; rack->r_ent_rec_ns = 0; orig_cwnd = tp->snd_cwnd; tp->snd_ssthresh = rack->r_ctl.rc_ssthresh_at_erec; tp->snd_recover = tp->snd_una; rack_log_to_prr(rack, 14, orig_cwnd, __LINE__); EXIT_RECOVERY(tp->t_flags); } rack->r_might_revert = 0; } } #ifdef TCP_SAD_DETECTION static void rack_merge_out_sacks(struct tcp_rack *rack) { struct rack_sendmap *cur, *next, *rsm, *trsm = NULL; cur = tqhash_min(rack->r_ctl.tqh); while(cur) { next = tqhash_next(rack->r_ctl.tqh, cur); /* * The idea is to go through all and merge back * together the pieces sent together, */ if ((next != NULL) && (cur->r_tim_lastsent[0] == next->r_tim_lastsent[0])) { rack_merge_rsm(rack, cur, next); } else { cur = next; } } /* * now treat it like a rxt event, everything is outstanding * and sent nothing acvked and dupacks are all zero. If this * is not an attacker it will have to dupack its way through * it all. */ TAILQ_INIT(&rack->r_ctl.rc_tmap); TQHASH_FOREACH(rsm, rack->r_ctl.tqh) { rsm->r_dupack = 0; /* We must re-add it back to the tlist */ if (trsm == NULL) { TAILQ_INSERT_HEAD(&rack->r_ctl.rc_tmap, rsm, r_tnext); } else { TAILQ_INSERT_AFTER(&rack->r_ctl.rc_tmap, trsm, rsm, r_tnext); } rsm->r_in_tmap = 1; trsm = rsm; rsm->r_flags &= ~(RACK_ACKED | RACK_SACK_PASSED | RACK_WAS_SACKPASS | RACK_RWND_COLLAPSED); } sack_filter_clear(&rack->r_ctl.rack_sf, rack->rc_tp->snd_una); } static void rack_do_detection(struct tcpcb *tp, struct tcp_rack *rack, uint32_t bytes_this_ack, uint32_t segsiz) { int do_detection = 0; if (rack->sack_attack_disable || rack->rc_suspicious) { /* * If we have been disabled we must detect * to possibly reverse it. Or if the guy has * sent in suspicious sacks we want to do detection too. */ do_detection = 1; } else if ((rack->do_detection || tcp_force_detection) && (tcp_sack_to_ack_thresh > 0) && (tcp_sack_to_move_thresh > 0) && (rack->r_ctl.rc_num_maps_alloced > tcp_map_minimum)) { /* * We only detect here if: * 1) System wide forcing is on do_detection is on * * 2) We have thresholds for move and ack (set one to 0 and we are off) * * 3) We have maps allocated larger than our min (500). */ do_detection = 1; } if (do_detection > 0) { /* * We have thresholds set to find * possible attackers and disable sack. * Check them. */ uint64_t ackratio, moveratio, movetotal; /* Log detecting */ rack_log_sad(rack, 1); /* Do we establish a ack ratio */ if ((rack->r_ctl.sack_count > tcp_map_minimum) || (rack->rc_suspicious == 1) || (rack->sack_attack_disable > 0)) { ackratio = (uint64_t)(rack->r_ctl.sack_count); ackratio *= (uint64_t)(1000); if (rack->r_ctl.ack_count) ackratio /= (uint64_t)(rack->r_ctl.ack_count); else { /* We can hit this due to ack totals degregation (via small sacks) */ ackratio = 1000; } } else { /* * No ack ratio needed if we have not * seen more sacks then the number of map entries. * The exception to that is if we have disabled sack then * we need to find a ratio. */ ackratio = 0; } if ((rack->sack_attack_disable == 0) && (ackratio > rack_highest_sack_thresh_seen)) rack_highest_sack_thresh_seen = (uint32_t)ackratio; /* Do we establish a move ratio? */ if ((rack->r_ctl.sack_moved_extra > tcp_map_minimum) || (rack->rc_suspicious == 1) || (rack->sack_attack_disable > 0)) { /* * We need to have more sack moves than maps * allocated to have a move ratio considered. */ movetotal = rack->r_ctl.sack_moved_extra; movetotal += rack->r_ctl.sack_noextra_move; moveratio = rack->r_ctl.sack_moved_extra; moveratio *= (uint64_t)1000; if (movetotal) moveratio /= movetotal; else { /* No moves, thats pretty good */ moveratio = 0; } } else { /* * Not enough moves have occured to consider * if we are out of whack in that ratio. * The exception to that is if we have disabled sack then * we need to find a ratio. */ moveratio = 0; } if ((rack->sack_attack_disable == 0) && (moveratio > rack_highest_move_thresh_seen)) rack_highest_move_thresh_seen = (uint32_t)moveratio; /* Now the tests */ if (rack->sack_attack_disable == 0) { /* Not disabled, do we need to disable? */ if ((ackratio > tcp_sack_to_ack_thresh) && (moveratio > tcp_sack_to_move_thresh)) { /* Disable sack processing */ tcp_trace_point(rack->rc_tp, TCP_TP_SAD_TRIGGERED); rack->sack_attack_disable = 1; /* set it so we have the built in delay */ rack->r_ctl.ack_during_sd = 1; if (rack_merge_out_sacks_on_attack) rack_merge_out_sacks(rack); counter_u64_add(rack_sack_attacks_detected, 1); tcp_trace_point(rack->rc_tp, TCP_TP_SAD_TRIGGERED); /* Clamp the cwnd at flight size */ rack->r_ctl.rc_saved_cwnd = rack->rc_tp->snd_cwnd; rack->rc_tp->snd_cwnd = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); rack_log_sad(rack, 2); } } else { /* We are sack-disabled check for false positives */ if ((ackratio <= tcp_restoral_thresh) || ((rack_merge_out_sacks_on_attack == 0) && (rack->rc_suspicious == 0) && (rack->r_ctl.rc_num_maps_alloced <= (tcp_map_minimum/2)))) { rack->sack_attack_disable = 0; rack_log_sad(rack, 3); /* Restart counting */ rack->r_ctl.sack_count = 0; rack->r_ctl.sack_moved_extra = 0; rack->r_ctl.sack_noextra_move = 1; rack->rc_suspicious = 0; rack->r_ctl.ack_count = max(1, (bytes_this_ack / segsiz)); counter_u64_add(rack_sack_attacks_reversed, 1); /* Restore the cwnd */ if (rack->r_ctl.rc_saved_cwnd > rack->rc_tp->snd_cwnd) rack->rc_tp->snd_cwnd = rack->r_ctl.rc_saved_cwnd; } } } } #endif static int rack_note_dsack(struct tcp_rack *rack, tcp_seq start, tcp_seq end) { uint32_t am, l_end; int was_tlp = 0; if (SEQ_GT(end, start)) am = end - start; else am = 0; if ((rack->rc_last_tlp_acked_set ) && (SEQ_GEQ(start, rack->r_ctl.last_tlp_acked_start)) && (SEQ_LEQ(end, rack->r_ctl.last_tlp_acked_end))) { /* * The DSACK is because of a TLP which we don't * do anything with the reordering window over since * it was not reordering that caused the DSACK but * our previous retransmit TLP. */ rack_log_dsack_event(rack, 7, __LINE__, start, end); was_tlp = 1; goto skip_dsack_round; } if (rack->rc_last_sent_tlp_seq_valid) { l_end = rack->r_ctl.last_sent_tlp_seq + rack->r_ctl.last_sent_tlp_len; if (SEQ_GEQ(start, rack->r_ctl.last_sent_tlp_seq) && (SEQ_LEQ(end, l_end))) { /* * This dsack is from the last sent TLP, ignore it * for reordering purposes. */ rack_log_dsack_event(rack, 7, __LINE__, start, end); was_tlp = 1; goto skip_dsack_round; } } if (rack->rc_dsack_round_seen == 0) { rack->rc_dsack_round_seen = 1; rack->r_ctl.dsack_round_end = rack->rc_tp->snd_max; rack->r_ctl.num_dsack++; rack->r_ctl.dsack_persist = 16; /* 16 is from the standard */ rack_log_dsack_event(rack, 2, __LINE__, 0, 0); } skip_dsack_round: /* * We keep track of how many DSACK blocks we get * after a recovery incident. */ rack->r_ctl.dsack_byte_cnt += am; if (!IN_FASTRECOVERY(rack->rc_tp->t_flags) && rack->r_ctl.retran_during_recovery && (rack->r_ctl.dsack_byte_cnt >= rack->r_ctl.retran_during_recovery)) { /* * False recovery most likely culprit is reordering. If * nothing else is missing we need to revert. */ rack->r_might_revert = 1; rack_handle_might_revert(rack->rc_tp, rack); rack->r_might_revert = 0; rack->r_ctl.retran_during_recovery = 0; rack->r_ctl.dsack_byte_cnt = 0; } return (was_tlp); } static uint32_t do_rack_compute_pipe(struct tcpcb *tp, struct tcp_rack *rack, uint32_t snd_una) { return (((tp->snd_max - snd_una) - rack->r_ctl.rc_sacked) + rack->r_ctl.rc_holes_rxt); } static int32_t rack_compute_pipe(struct tcpcb *tp) { return ((int32_t)do_rack_compute_pipe(tp, (struct tcp_rack *)tp->t_fb_ptr, tp->snd_una)); } static void rack_update_prr(struct tcpcb *tp, struct tcp_rack *rack, uint32_t changed, tcp_seq th_ack) { /* Deal with changed and PRR here (in recovery only) */ uint32_t pipe, snd_una; rack->r_ctl.rc_prr_delivered += changed; if (sbavail(&rack->rc_inp->inp_socket->so_snd) <= (tp->snd_max - tp->snd_una)) { /* * It is all outstanding, we are application limited * and thus we don't need more room to send anything. * Note we use tp->snd_una here and not th_ack because * the data as yet not been cut from the sb. */ rack->r_ctl.rc_prr_sndcnt = 0; return; } /* Compute prr_sndcnt */ if (SEQ_GT(tp->snd_una, th_ack)) { snd_una = tp->snd_una; } else { snd_una = th_ack; } pipe = do_rack_compute_pipe(tp, rack, snd_una); if (pipe > tp->snd_ssthresh) { long sndcnt; sndcnt = rack->r_ctl.rc_prr_delivered * tp->snd_ssthresh; if (rack->r_ctl.rc_prr_recovery_fs > 0) sndcnt /= (long)rack->r_ctl.rc_prr_recovery_fs; else { rack->r_ctl.rc_prr_sndcnt = 0; rack_log_to_prr(rack, 9, 0, __LINE__); sndcnt = 0; } sndcnt++; if (sndcnt > (long)rack->r_ctl.rc_prr_out) sndcnt -= rack->r_ctl.rc_prr_out; else sndcnt = 0; rack->r_ctl.rc_prr_sndcnt = sndcnt; rack_log_to_prr(rack, 10, 0, __LINE__); } else { uint32_t limit; if (rack->r_ctl.rc_prr_delivered > rack->r_ctl.rc_prr_out) limit = (rack->r_ctl.rc_prr_delivered - rack->r_ctl.rc_prr_out); else limit = 0; if (changed > limit) limit = changed; limit += ctf_fixed_maxseg(tp); if (tp->snd_ssthresh > pipe) { rack->r_ctl.rc_prr_sndcnt = min((tp->snd_ssthresh - pipe), limit); rack_log_to_prr(rack, 11, 0, __LINE__); } else { rack->r_ctl.rc_prr_sndcnt = min(0, limit); rack_log_to_prr(rack, 12, 0, __LINE__); } } } static void rack_log_ack(struct tcpcb *tp, struct tcpopt *to, struct tcphdr *th, int entered_recovery, int dup_ack_struck, int *dsack_seen, int *sacks_seen) { uint32_t changed; struct tcp_rack *rack; struct rack_sendmap *rsm; struct sackblk sack, sack_blocks[TCP_MAX_SACK + 1]; register uint32_t th_ack; int32_t i, j, k, num_sack_blks = 0; uint32_t cts, acked, ack_point; int loop_start = 0, moved_two = 0, no_extra = 0; uint32_t tsused; uint32_t segsiz, o_cnt; INP_WLOCK_ASSERT(tptoinpcb(tp)); if (tcp_get_flags(th) & TH_RST) { /* We don't log resets */ return; } rack = (struct tcp_rack *)tp->t_fb_ptr; cts = tcp_get_usecs(NULL); rsm = tqhash_min(rack->r_ctl.tqh); changed = 0; th_ack = th->th_ack; if (rack->sack_attack_disable == 0) rack_do_decay(rack); segsiz = ctf_fixed_maxseg(rack->rc_tp); if (BYTES_THIS_ACK(tp, th) >= segsiz) { /* * You only get credit for * MSS and greater (and you get extra * credit for larger cum-ack moves). */ int ac; ac = BYTES_THIS_ACK(tp, th) / ctf_fixed_maxseg(rack->rc_tp); rack->r_ctl.ack_count += ac; counter_u64_add(rack_ack_total, ac); } if (rack->r_ctl.ack_count > 0xfff00000) { /* * reduce the number to keep us under * a uint32_t. */ rack->r_ctl.ack_count /= 2; rack->r_ctl.sack_count /= 2; } if (SEQ_GT(th_ack, tp->snd_una)) { rack_log_progress_event(rack, tp, ticks, PROGRESS_UPDATE, __LINE__); tp->t_acktime = ticks; } if (rsm && SEQ_GT(th_ack, rsm->r_start)) changed = th_ack - rsm->r_start; if (changed) { rack_process_to_cumack(tp, rack, th_ack, cts, to, tcp_tv_to_lusectick(&rack->r_ctl.act_rcv_time)); } if ((to->to_flags & TOF_SACK) == 0) { /* We are done nothing left and no sack. */ rack_handle_might_revert(tp, rack); /* * For cases where we struck a dup-ack * with no SACK, add to the changes so * PRR will work right. */ if (dup_ack_struck && (changed == 0)) { changed += ctf_fixed_maxseg(rack->rc_tp); } goto out; } /* Sack block processing */ if (SEQ_GT(th_ack, tp->snd_una)) ack_point = th_ack; else ack_point = tp->snd_una; for (i = 0; i < to->to_nsacks; i++) { bcopy((to->to_sacks + i * TCPOLEN_SACK), &sack, sizeof(sack)); sack.start = ntohl(sack.start); sack.end = ntohl(sack.end); if (SEQ_GT(sack.end, sack.start) && SEQ_GT(sack.start, ack_point) && SEQ_LT(sack.start, tp->snd_max) && SEQ_GT(sack.end, ack_point) && SEQ_LEQ(sack.end, tp->snd_max)) { sack_blocks[num_sack_blks] = sack; num_sack_blks++; } else if (SEQ_LEQ(sack.start, th_ack) && SEQ_LEQ(sack.end, th_ack)) { int was_tlp; if (dsack_seen != NULL) *dsack_seen = 1; was_tlp = rack_note_dsack(rack, sack.start, sack.end); /* * Its a D-SACK block. */ tcp_record_dsack(tp, sack.start, sack.end, was_tlp); } } if (rack->rc_dsack_round_seen) { /* Is the dsack roound over? */ if (SEQ_GEQ(th_ack, rack->r_ctl.dsack_round_end)) { /* Yes it is */ rack->rc_dsack_round_seen = 0; rack_log_dsack_event(rack, 3, __LINE__, 0, 0); } } /* * Sort the SACK blocks so we can update the rack scoreboard with * just one pass. */ o_cnt = num_sack_blks; num_sack_blks = sack_filter_blks(&rack->r_ctl.rack_sf, sack_blocks, num_sack_blks, th->th_ack); ctf_log_sack_filter(rack->rc_tp, num_sack_blks, sack_blocks); if (sacks_seen != NULL) *sacks_seen = num_sack_blks; if (num_sack_blks == 0) { /* Nothing to sack, but we need to update counts */ if ((o_cnt == 1) && (*dsack_seen != 1)) rack->r_ctl.sack_count++; else if (o_cnt > 1) rack->r_ctl.sack_count++; goto out_with_totals; } if (rack->sack_attack_disable) { /* * An attacker disablement is in place, for * every sack block that is not at least a full MSS * count up sack_count. */ for (i = 0; i < num_sack_blks; i++) { if ((sack_blocks[i].end - sack_blocks[i].start) < segsiz) { rack->r_ctl.sack_count++; } if (rack->r_ctl.sack_count > 0xfff00000) { /* * reduce the number to keep us under * a uint32_t. */ rack->r_ctl.ack_count /= 2; rack->r_ctl.sack_count /= 2; } } goto out; } /* Its a sack of some sort */ rack->r_ctl.sack_count += num_sack_blks; if (rack->r_ctl.sack_count > 0xfff00000) { /* * reduce the number to keep us under * a uint32_t. */ rack->r_ctl.ack_count /= 2; rack->r_ctl.sack_count /= 2; } if (num_sack_blks < 2) { /* Only one, we don't need to sort */ goto do_sack_work; } /* Sort the sacks */ for (i = 0; i < num_sack_blks; i++) { for (j = i + 1; j < num_sack_blks; j++) { if (SEQ_GT(sack_blocks[i].end, sack_blocks[j].end)) { sack = sack_blocks[i]; sack_blocks[i] = sack_blocks[j]; sack_blocks[j] = sack; } } } /* * Now are any of the sack block ends the same (yes some * implementations send these)? */ again: if (num_sack_blks == 0) goto out_with_totals; if (num_sack_blks > 1) { for (i = 0; i < num_sack_blks; i++) { for (j = i + 1; j < num_sack_blks; j++) { if (sack_blocks[i].end == sack_blocks[j].end) { /* * Ok these two have the same end we * want the smallest end and then * throw away the larger and start * again. */ if (SEQ_LT(sack_blocks[j].start, sack_blocks[i].start)) { /* * The second block covers * more area use that */ sack_blocks[i].start = sack_blocks[j].start; } /* * Now collapse out the dup-sack and * lower the count */ for (k = (j + 1); k < num_sack_blks; k++) { sack_blocks[j].start = sack_blocks[k].start; sack_blocks[j].end = sack_blocks[k].end; j++; } num_sack_blks--; goto again; } } } } do_sack_work: /* * First lets look to see if * we have retransmitted and * can use the transmit next? */ rsm = TAILQ_FIRST(&rack->r_ctl.rc_tmap); if (rsm && SEQ_GT(sack_blocks[0].end, rsm->r_start) && SEQ_LT(sack_blocks[0].start, rsm->r_end)) { /* * We probably did the FR and the next * SACK in continues as we would expect. */ acked = rack_proc_sack_blk(tp, rack, &sack_blocks[0], to, &rsm, cts, &no_extra, &moved_two, segsiz); if (acked) { rack->r_wanted_output = 1; changed += acked; } if (num_sack_blks == 1) { /* * This is what we would expect from * a normal implementation to happen * after we have retransmitted the FR, * i.e the sack-filter pushes down * to 1 block and the next to be retransmitted * is the sequence in the sack block (has more * are acked). Count this as ACK'd data to boost * up the chances of recovering any false positives. */ rack->r_ctl.ack_count += (acked / ctf_fixed_maxseg(rack->rc_tp)); counter_u64_add(rack_ack_total, (acked / ctf_fixed_maxseg(rack->rc_tp))); counter_u64_add(rack_express_sack, 1); if (rack->r_ctl.ack_count > 0xfff00000) { /* * reduce the number to keep us under * a uint32_t. */ rack->r_ctl.ack_count /= 2; rack->r_ctl.sack_count /= 2; } if (moved_two) { /* * If we did not get a SACK for at least a MSS and * had to move at all, or if we moved more than our * threshold, it counts against the "extra" move. */ rack->r_ctl.sack_moved_extra += moved_two; rack->r_ctl.sack_noextra_move += no_extra; counter_u64_add(rack_move_some, 1); } else { /* * else we did not have to move * any more than we would expect. */ rack->r_ctl.sack_noextra_move += no_extra; rack->r_ctl.sack_noextra_move++; counter_u64_add(rack_move_none, 1); } if ((rack->r_ctl.sack_moved_extra > 0xfff00000) || (rack->r_ctl.sack_noextra_move > 0xfff00000)) { rack->r_ctl.sack_moved_extra /= 2; rack->r_ctl.sack_noextra_move /= 2; } goto out_with_totals; } else { /* * Start the loop through the * rest of blocks, past the first block. */ loop_start = 1; } } counter_u64_add(rack_sack_total, 1); rsm = rack->r_ctl.rc_sacklast; for (i = loop_start; i < num_sack_blks; i++) { acked = rack_proc_sack_blk(tp, rack, &sack_blocks[i], to, &rsm, cts, &no_extra, &moved_two, segsiz); if (acked) { rack->r_wanted_output = 1; changed += acked; } if (moved_two) { /* * If we did not get a SACK for at least a MSS and * had to move at all, or if we moved more than our * threshold, it counts against the "extra" move. */ rack->r_ctl.sack_moved_extra += moved_two; rack->r_ctl.sack_noextra_move += no_extra; counter_u64_add(rack_move_some, 1); } else { /* * else we did not have to move * any more than we would expect. */ rack->r_ctl.sack_noextra_move += no_extra; rack->r_ctl.sack_noextra_move++; counter_u64_add(rack_move_none, 1); } if ((rack->r_ctl.sack_moved_extra > 0xfff00000) || (rack->r_ctl.sack_noextra_move > 0xfff00000)) { rack->r_ctl.sack_moved_extra /= 2; rack->r_ctl.sack_noextra_move /= 2; } if (moved_two && (acked < ctf_fixed_maxseg(rack->rc_tp))) { /* * If the SACK was not a full MSS then * we add to sack_count the number of * MSS's (or possibly more than * a MSS if its a TSO send) we had to skip by. */ rack->r_ctl.sack_count += moved_two; if (rack->r_ctl.sack_count > 0xfff00000) { rack->r_ctl.ack_count /= 2; rack->r_ctl.sack_count /= 2; } counter_u64_add(rack_sack_total, moved_two); } /* * Now we need to setup for the next * round. First we make sure we won't * exceed the size of our uint32_t on * the various counts, and then clear out * moved_two. */ moved_two = 0; no_extra = 0; } out_with_totals: if (num_sack_blks > 1) { /* * You get an extra stroke if * you have more than one sack-blk, this * could be where we are skipping forward * and the sack-filter is still working, or * it could be an attacker constantly * moving us. */ rack->r_ctl.sack_moved_extra++; counter_u64_add(rack_move_some, 1); } out: #ifdef TCP_SAD_DETECTION rack_do_detection(tp, rack, BYTES_THIS_ACK(tp, th), ctf_fixed_maxseg(rack->rc_tp)); #endif if (changed) { /* Something changed cancel the rack timer */ rack_timer_cancel(tp, rack, rack->r_ctl.rc_rcvtime, __LINE__); } tsused = tcp_get_usecs(NULL); rsm = tcp_rack_output(tp, rack, tsused); if ((!IN_FASTRECOVERY(tp->t_flags)) && rsm && ((rsm->r_flags & RACK_MUST_RXT) == 0)) { /* Enter recovery */ entered_recovery = 1; rack_cong_signal(tp, CC_NDUPACK, tp->snd_una, __LINE__); /* * When we enter recovery we need to assure we send * one packet. */ if (rack->rack_no_prr == 0) { rack->r_ctl.rc_prr_sndcnt = ctf_fixed_maxseg(tp); rack_log_to_prr(rack, 8, 0, __LINE__); } rack->r_timer_override = 1; rack->r_early = 0; rack->r_ctl.rc_agg_early = 0; } else if (IN_FASTRECOVERY(tp->t_flags) && rsm && (rack->r_rr_config == 3)) { /* * Assure we can output and we get no * remembered pace time except the retransmit. */ rack->r_timer_override = 1; rack->r_ctl.rc_hpts_flags &= ~PACE_PKT_OUTPUT; rack->r_ctl.rc_resend = rsm; } if (IN_FASTRECOVERY(tp->t_flags) && (rack->rack_no_prr == 0) && (entered_recovery == 0)) { rack_update_prr(tp, rack, changed, th_ack); if ((rsm && (rack->r_ctl.rc_prr_sndcnt >= ctf_fixed_maxseg(tp)) && ((tcp_in_hpts(rack->rc_tp) == 0) && ((rack->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) == 0)))) { /* * If you are pacing output you don't want * to override. */ rack->r_early = 0; rack->r_ctl.rc_agg_early = 0; rack->r_timer_override = 1; } } } static void rack_strike_dupack(struct tcp_rack *rack) { struct rack_sendmap *rsm; rsm = TAILQ_FIRST(&rack->r_ctl.rc_tmap); while (rsm) { /* * We need to skip anything already set * to be retransmitted. */ if ((rsm->r_dupack >= DUP_ACK_THRESHOLD) || (rsm->r_flags & RACK_MUST_RXT)) { rsm = TAILQ_NEXT(rsm, r_tnext); continue; } break; } if (rsm && (rsm->r_dupack < 0xff)) { rsm->r_dupack++; if (rsm->r_dupack >= DUP_ACK_THRESHOLD) { struct timeval tv; uint32_t cts; /* * Here we see if we need to retransmit. For * a SACK type connection if enough time has passed * we will get a return of the rsm. For a non-sack * connection we will get the rsm returned if the * dupack value is 3 or more. */ cts = tcp_get_usecs(&tv); rack->r_ctl.rc_resend = tcp_rack_output(rack->rc_tp, rack, cts); if (rack->r_ctl.rc_resend != NULL) { if (!IN_FASTRECOVERY(rack->rc_tp->t_flags)) { rack_cong_signal(rack->rc_tp, CC_NDUPACK, rack->rc_tp->snd_una, __LINE__); } rack->r_wanted_output = 1; rack->r_timer_override = 1; rack_log_retran_reason(rack, rsm, __LINE__, 1, 3); } } else { rack_log_retran_reason(rack, rsm, __LINE__, 0, 3); } } } static void rack_check_bottom_drag(struct tcpcb *tp, struct tcp_rack *rack, struct socket *so) { uint32_t segsiz, minseg; segsiz = ctf_fixed_maxseg(tp); minseg = segsiz; if (tp->snd_max == tp->snd_una) { /* * We are doing dynamic pacing and we are way * under. Basically everything got acked while * we were still waiting on the pacer to expire. * * This means we need to boost the b/w in * addition to any earlier boosting of * the multiplier. */ uint64_t lt_bw; lt_bw = rack_get_lt_bw(rack); rack->rc_dragged_bottom = 1; rack_validate_multipliers_at_or_above100(rack); if ((rack->r_ctl.rack_rs.rs_flags & RACK_RTT_VALID) && (lt_bw > 0)) { /* * Lets use the long-term b/w we have * been getting as a base. */ if (rack->rc_gp_filled == 0) { if (lt_bw > ONE_POINT_TWO_MEG) { /* * If we have no measurement * don't let us set in more than * 1.2Mbps. If we are still too * low after pacing with this we * will hopefully have a max b/w * available to sanity check things. */ lt_bw = ONE_POINT_TWO_MEG; } rack->r_ctl.rc_rtt_diff = 0; rack->r_ctl.gp_bw = lt_bw; rack->rc_gp_filled = 1; if (rack->r_ctl.num_measurements < RACK_REQ_AVG) rack->r_ctl.num_measurements = RACK_REQ_AVG; rack_set_pace_segments(rack->rc_tp, rack, __LINE__, NULL); } else if (lt_bw > rack->r_ctl.gp_bw) { rack->r_ctl.rc_rtt_diff = 0; if (rack->r_ctl.num_measurements < RACK_REQ_AVG) rack->r_ctl.num_measurements = RACK_REQ_AVG; rack->r_ctl.gp_bw = lt_bw; rack_set_pace_segments(rack->rc_tp, rack, __LINE__, NULL); } else rack_increase_bw_mul(rack, -1, 0, 0, 1); if ((rack->gp_ready == 0) && (rack->r_ctl.num_measurements >= rack->r_ctl.req_measurements)) { /* We have enough measurements now */ rack->gp_ready = 1; if (rack->dgp_on || rack->rack_hibeta) rack_set_cc_pacing(rack); if (rack->defer_options) rack_apply_deferred_options(rack); } } else { /* * zero rtt possibly?, settle for just an old increase. */ rack_increase_bw_mul(rack, -1, 0, 0, 1); } } else if ((IN_FASTRECOVERY(tp->t_flags) == 0) && (sbavail(&so->so_snd) > max((segsiz * (4 + rack_req_segs)), minseg)) && (rack->r_ctl.cwnd_to_use > max((segsiz * (rack_req_segs + 2)), minseg)) && (tp->snd_wnd > max((segsiz * (rack_req_segs + 2)), minseg)) && (ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked) <= (segsiz * rack_req_segs))) { /* * We are doing dynamic GP pacing and * we have everything except 1MSS or less * bytes left out. We are still pacing away. * And there is data that could be sent, This * means we are inserting delayed ack time in * our measurements because we are pacing too slow. */ rack_validate_multipliers_at_or_above100(rack); rack->rc_dragged_bottom = 1; rack_increase_bw_mul(rack, -1, 0, 0, 1); } } #ifdef TCP_REQUEST_TRK static void rack_log_hybrid(struct tcp_rack *rack, uint32_t seq, struct tcp_sendfile_track *cur, uint8_t mod, int line, int err) { int do_log; do_log = tcp_bblogging_on(rack->rc_tp); if (do_log == 0) { if ((do_log = tcp_bblogging_point_on(rack->rc_tp, TCP_BBPOINT_REQ_LEVEL_LOGGING) )== 0) return; /* We only allow the three below with point logging on */ if ((mod != HYBRID_LOG_RULES_APP) && (mod != HYBRID_LOG_RULES_SET) && (mod != HYBRID_LOG_REQ_COMP)) return; } if (do_log) { union tcp_log_stackspecific log; struct timeval tv; /* Convert our ms to a microsecond */ memset(&log, 0, sizeof(log)); log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.flex1 = seq; log.u_bbr.cwnd_gain = line; if (cur != NULL) { uint64_t off; log.u_bbr.flex2 = cur->start_seq; log.u_bbr.flex3 = cur->end_seq; log.u_bbr.flex4 = (uint32_t)((cur->localtime >> 32) & 0x00000000ffffffff); log.u_bbr.flex5 = (uint32_t)(cur->localtime & 0x00000000ffffffff); log.u_bbr.flex6 = cur->flags; log.u_bbr.pkts_out = cur->hybrid_flags; log.u_bbr.rttProp = cur->timestamp; log.u_bbr.cur_del_rate = cur->cspr; log.u_bbr.bw_inuse = cur->start; log.u_bbr.applimited = (uint32_t)(cur->end & 0x00000000ffffffff); log.u_bbr.delivered = (uint32_t)((cur->end >> 32) & 0x00000000ffffffff) ; log.u_bbr.epoch = (uint32_t)(cur->deadline & 0x00000000ffffffff); log.u_bbr.lt_epoch = (uint32_t)((cur->deadline >> 32) & 0x00000000ffffffff) ; log.u_bbr.bbr_state = 1; #ifdef TCP_REQUEST_TRK off = (uint64_t)(cur) - (uint64_t)(&rack->rc_tp->t_tcpreq_info[0]); log.u_bbr.use_lt_bw = (uint8_t)(off / sizeof(struct tcp_sendfile_track)); #endif } else { log.u_bbr.flex2 = err; } /* * Fill in flex7 to be CHD (catchup|hybrid|DGP) */ log.u_bbr.flex7 = rack->rc_catch_up; log.u_bbr.flex7 <<= 1; log.u_bbr.flex7 |= rack->rc_hybrid_mode; log.u_bbr.flex7 <<= 1; log.u_bbr.flex7 |= rack->dgp_on; log.u_bbr.flex8 = mod; log.u_bbr.delRate = rack->r_ctl.bw_rate_cap; log.u_bbr.bbr_substate = rack->r_ctl.client_suggested_maxseg; log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); log.u_bbr.pkt_epoch = rack->rc_tp->tcp_hybrid_start; log.u_bbr.lost = rack->rc_tp->tcp_hybrid_error; log.u_bbr.pacing_gain = (uint16_t)rack->rc_tp->tcp_hybrid_stop; tcp_log_event(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, TCP_HYBRID_PACING_LOG, 0, 0, &log, false, NULL, __func__, __LINE__, &tv); } } #endif #ifdef TCP_REQUEST_TRK static void rack_set_dgp_hybrid_mode(struct tcp_rack *rack, tcp_seq seq, uint32_t len) { struct tcp_sendfile_track *rc_cur; struct tcpcb *tp; int err = 0; rc_cur = tcp_req_find_req_for_seq(rack->rc_tp, seq); if (rc_cur == NULL) { /* If not in the beginning what about the end piece */ if (rack->rc_hybrid_mode) rack_log_hybrid(rack, seq, NULL, HYBRID_LOG_NO_RANGE, __LINE__, err); rc_cur = tcp_req_find_req_for_seq(rack->rc_tp, (seq + len - 1)); } else { err = 12345; } /* If we find no parameters we are in straight DGP mode */ if(rc_cur == NULL) { /* None found for this seq, just DGP for now */ rack->r_ctl.client_suggested_maxseg = 0; rack->rc_catch_up = 0; rack->r_ctl.bw_rate_cap = 0; if (rack->rc_hybrid_mode) rack_log_hybrid(rack, (seq + len - 1), NULL, HYBRID_LOG_NO_RANGE, __LINE__, err); if (rack->r_ctl.rc_last_sft) { rack->r_ctl.rc_last_sft = NULL; } return; } if ((rc_cur->hybrid_flags & TCP_HYBRID_PACING_WASSET) == 0) { /* This entry was never setup for hybrid pacing on/off etc */ return; } /* * Ok if we have a new entry *or* have never * set up an entry we need to proceed. If * we have already set it up this entry we * just continue along with what we already * setup. */ tp = rack->rc_tp; if ((rack->r_ctl.rc_last_sft != NULL) && (rack->r_ctl.rc_last_sft == rc_cur)) { /* Its already in place */ if (rack->rc_hybrid_mode) rack_log_hybrid(rack, seq, rc_cur, HYBRID_LOG_ISSAME, __LINE__, 0); return; } if (rack->rc_hybrid_mode == 0) { rack->r_ctl.rc_last_sft = rc_cur; rack_log_hybrid(rack, seq, rc_cur, HYBRID_LOG_RULES_APP, __LINE__, 0); return; } if ((rc_cur->hybrid_flags & TCP_HYBRID_PACING_CSPR) && rc_cur->cspr){ /* Compensate for all the header overhead's */ rack->r_ctl.bw_rate_cap = rack_compensate_for_linerate(rack, rc_cur->cspr); } else rack->r_ctl.bw_rate_cap = 0; if (rc_cur->hybrid_flags & TCP_HYBRID_PACING_H_MS) rack->r_ctl.client_suggested_maxseg = rc_cur->hint_maxseg; else rack->r_ctl.client_suggested_maxseg = 0; if ((rc_cur->hybrid_flags & TCP_HYBRID_PACING_CU) && (rc_cur->cspr > 0)) { uint64_t len; rack->rc_catch_up = 1; /* * Calculate the deadline time, first set the * time to when the request arrived. */ rc_cur->deadline = rc_cur->localtime; /* * Next calculate the length and compensate for * TLS if need be. */ len = rc_cur->end - rc_cur->start; if (tp->t_inpcb.inp_socket->so_snd.sb_tls_info) { /* * This session is doing TLS. Take a swag guess * at the overhead. */ len += tcp_estimate_tls_overhead(tp->t_inpcb.inp_socket, len); } /* * Now considering the size, and the cspr, what is the time that * would be required at the cspr rate. Here we use the raw * cspr value since the client only looks at the raw data. We * do use len which includes TLS overhead, but not the TCP/IP etc. * That will get made up for in the CU pacing rate set. */ len *= HPTS_USEC_IN_SEC; len /= rc_cur->cspr; rc_cur->deadline += len; } else { rack->rc_catch_up = 0; rc_cur->deadline = 0; } if (rack->r_ctl.client_suggested_maxseg != 0) { /* * We need to reset the max pace segs if we have a * client_suggested_maxseg. */ rack_set_pace_segments(tp, rack, __LINE__, NULL); } rack_log_hybrid(rack, seq, rc_cur, HYBRID_LOG_RULES_APP, __LINE__, 0); /* Remember it for next time and for CU mode */ rack->r_ctl.rc_last_sft = rc_cur; } #endif static void rack_chk_req_and_hybrid_on_out(struct tcp_rack *rack, tcp_seq seq, uint32_t len, uint64_t cts) { #ifdef TCP_REQUEST_TRK struct tcp_sendfile_track *ent; ent = rack->r_ctl.rc_last_sft; if ((ent == NULL) || (ent->flags == TCP_TRK_TRACK_FLG_EMPTY) || (SEQ_GEQ(seq, ent->end_seq))) { /* Time to update the track. */ rack_set_dgp_hybrid_mode(rack, seq, len); ent = rack->r_ctl.rc_last_sft; } /* Out of all */ if (ent == NULL) { return; } if (SEQ_LT(ent->end_seq, (seq + len))) { /* * This is the case where our end_seq guess * was wrong. This is usually due to TLS having * more bytes then our guess. It could also be the * case that the client sent in two requests closely * and the SB is full of both so we are sending part * of each (end|beg). In such a case lets move this * guys end to match the end of this send. That * way it will complete when all of it is acked. */ ent->end_seq = (seq + len); if (rack->rc_hybrid_mode) rack_log_hybrid_bw(rack, seq, len, 0, 0, HYBRID_LOG_EXTEND, 0, ent, __LINE__); } /* Now validate we have set the send time of this one */ if ((ent->flags & TCP_TRK_TRACK_FLG_FSND) == 0) { ent->flags |= TCP_TRK_TRACK_FLG_FSND; ent->first_send = cts; ent->sent_at_fs = rack->rc_tp->t_sndbytes; ent->rxt_at_fs = rack->rc_tp->t_snd_rxt_bytes; } #endif } static void rack_gain_for_fastoutput(struct tcp_rack *rack, struct tcpcb *tp, struct socket *so, uint32_t acked_amount) { /* * The fast output path is enabled and we * have moved the cumack forward. Lets see if * we can expand forward the fast path length by * that amount. What we would ideally like to * do is increase the number of bytes in the * fast path block (left_to_send) by the * acked amount. However we have to gate that * by two factors: * 1) The amount outstanding and the rwnd of the peer * (i.e. we don't want to exceed the rwnd of the peer). * * 2) The amount of data left in the socket buffer (i.e. * we can't send beyond what is in the buffer). * * Note that this does not take into account any increase * in the cwnd. We will only extend the fast path by * what was acked. */ uint32_t new_total, gating_val; new_total = acked_amount + rack->r_ctl.fsb.left_to_send; gating_val = min((sbavail(&so->so_snd) - (tp->snd_max - tp->snd_una)), (tp->snd_wnd - (tp->snd_max - tp->snd_una))); if (new_total <= gating_val) { /* We can increase left_to_send by the acked amount */ counter_u64_add(rack_extended_rfo, 1); rack->r_ctl.fsb.left_to_send = new_total; KASSERT((rack->r_ctl.fsb.left_to_send <= (sbavail(&rack->rc_inp->inp_socket->so_snd) - (tp->snd_max - tp->snd_una))), ("rack:%p left_to_send:%u sbavail:%u out:%u", rack, rack->r_ctl.fsb.left_to_send, sbavail(&rack->rc_inp->inp_socket->so_snd), (tp->snd_max - tp->snd_una))); } } static void rack_adjust_sendmap_head(struct tcp_rack *rack, struct sockbuf *sb) { /* * Here any sendmap entry that points to the * beginning mbuf must be adjusted to the correct * offset. This must be called with: * 1) The socket buffer locked * 2) snd_una adjusted to its new position. * * Note that (2) implies rack_ack_received has also * been called and all the sbcut's have been done. * * We grab the first mbuf in the socket buffer and * then go through the front of the sendmap, recalculating * the stored offset for any sendmap entry that has * that mbuf. We must use the sb functions to do this * since its possible an add was done has well as * the subtraction we may have just completed. This should * not be a penalty though, since we just referenced the sb * to go in and trim off the mbufs that we freed (of course * there will be a penalty for the sendmap references though). * * Note also with INVARIANT on, we validate with a KASSERT * that the first sendmap entry has a soff of 0. * */ struct mbuf *m; struct rack_sendmap *rsm; tcp_seq snd_una; #ifdef INVARIANTS int first_processed = 0; #endif snd_una = rack->rc_tp->snd_una; SOCKBUF_LOCK_ASSERT(sb); m = sb->sb_mb; rsm = tqhash_min(rack->r_ctl.tqh); if ((rsm == NULL) || (m == NULL)) { /* Nothing outstanding */ return; } /* The very first RSM's mbuf must point to the head mbuf in the sb */ KASSERT((rsm->m == m), ("Rack:%p sb:%p rsm:%p -- first rsm mbuf not aligned to sb", rack, sb, rsm)); while (rsm->m && (rsm->m == m)) { /* one to adjust */ #ifdef INVARIANTS struct mbuf *tm; uint32_t soff; tm = sbsndmbuf(sb, (rsm->r_start - snd_una), &soff); if ((rsm->orig_m_len != m->m_len) || (rsm->orig_t_space != M_TRAILINGROOM(m))){ rack_adjust_orig_mlen(rsm); } if (first_processed == 0) { KASSERT((rsm->soff == 0), ("Rack:%p rsm:%p -- rsm at head but soff not zero", rack, rsm)); first_processed = 1; } if ((rsm->soff != soff) || (rsm->m != tm)) { /* * This is not a fatal error, we anticipate it * might happen (the else code), so we count it here * so that under invariant we can see that it really * does happen. */ counter_u64_add(rack_adjust_map_bw, 1); } rsm->m = tm; rsm->soff = soff; if (tm) { rsm->orig_m_len = rsm->m->m_len; rsm->orig_t_space = M_TRAILINGROOM(rsm->m); } else { rsm->orig_m_len = 0; rsm->orig_t_space = 0; } #else rsm->m = sbsndmbuf(sb, (rsm->r_start - snd_una), &rsm->soff); if (rsm->m) { rsm->orig_m_len = rsm->m->m_len; rsm->orig_t_space = M_TRAILINGROOM(rsm->m); } else { rsm->orig_m_len = 0; rsm->orig_t_space = 0; } #endif rsm = tqhash_next(rack->r_ctl.tqh, rsm); if (rsm == NULL) break; } } #ifdef TCP_REQUEST_TRK static inline void rack_req_check_for_comp(struct tcp_rack *rack, tcp_seq th_ack) { struct tcp_sendfile_track *ent; int i; if ((rack->rc_hybrid_mode == 0) && (tcp_bblogging_point_on(rack->rc_tp, TCP_BBPOINT_REQ_LEVEL_LOGGING) == 0)) { /* * Just do normal completions hybrid pacing is not on * and CLDL is off as well. */ tcp_req_check_for_comp(rack->rc_tp, th_ack); return; } /* * Originally I was just going to find the th_ack associated * with an entry. But then I realized a large strech ack could * in theory ack two or more requests at once. So instead we * need to find all entries that are completed by th_ack not * just a single entry and do our logging. */ ent = tcp_req_find_a_req_that_is_completed_by(rack->rc_tp, th_ack, &i); while (ent != NULL) { /* * We may be doing hybrid pacing or CLDL and need more details possibly * so we do it manually instead of calling * tcp_req_check_for_comp() */ uint64_t laa, tim, data, cbw, ftim; /* Ok this ack frees it */ rack_log_hybrid(rack, th_ack, ent, HYBRID_LOG_REQ_COMP, __LINE__, 0); rack_log_hybrid_sends(rack, ent, __LINE__); /* calculate the time based on the ack arrival */ data = ent->end - ent->start; laa = tcp_tv_to_lusectick(&rack->r_ctl.act_rcv_time); if (ent->flags & TCP_TRK_TRACK_FLG_FSND) { if (ent->first_send > ent->localtime) ftim = ent->first_send; else ftim = ent->localtime; } else { /* TSNH */ ftim = ent->localtime; } if (laa > ent->localtime) tim = laa - ftim; else tim = 0; cbw = data * HPTS_USEC_IN_SEC; if (tim > 0) cbw /= tim; else cbw = 0; rack_log_hybrid_bw(rack, th_ack, cbw, tim, data, HYBRID_LOG_BW_MEASURE, 0, ent, __LINE__); /* * Check to see if we are freeing what we are pointing to send wise * if so be sure to NULL the pointer so we know we are no longer * set to anything. */ if (ent == rack->r_ctl.rc_last_sft) rack->r_ctl.rc_last_sft = NULL; /* Generate the log that the tcp_netflix call would have */ tcp_req_log_req_info(rack->rc_tp, ent, i, TCP_TRK_REQ_LOG_FREED, 0, 0); /* Free it and see if there is another one */ tcp_req_free_a_slot(rack->rc_tp, ent); ent = tcp_req_find_a_req_that_is_completed_by(rack->rc_tp, th_ack, &i); } } #endif /* * Return value of 1, we do not need to call rack_process_data(). * return value of 0, rack_process_data can be called. * For ret_val if its 0 the TCP is locked, if its non-zero * its unlocked and probably unsafe to touch the TCB. */ static int rack_process_ack(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, struct tcpopt *to, uint32_t tiwin, int32_t tlen, int32_t * ofia, int32_t thflags, int32_t *ret_val) { int32_t ourfinisacked = 0; int32_t nsegs, acked_amount; int32_t acked; struct mbuf *mfree; struct tcp_rack *rack; int32_t under_pacing = 0; int32_t recovery = 0; INP_WLOCK_ASSERT(tptoinpcb(tp)); rack = (struct tcp_rack *)tp->t_fb_ptr; if (SEQ_GT(th->th_ack, tp->snd_max)) { __ctf_do_dropafterack(m, tp, th, thflags, tlen, ret_val, &rack->r_ctl.challenge_ack_ts, &rack->r_ctl.challenge_ack_cnt); rack->r_wanted_output = 1; return (1); } if (rack->gp_ready && (rack->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT)) { under_pacing = 1; } if (SEQ_GEQ(th->th_ack, tp->snd_una) || to->to_nsacks) { int in_rec, dup_ack_struck = 0; int dsack_seen = 0, sacks_seen = 0; in_rec = IN_FASTRECOVERY(tp->t_flags); if (rack->rc_in_persist) { tp->t_rxtshift = 0; RACK_TCPT_RANGESET(tp->t_rxtcur, RACK_REXMTVAL(tp), rack_rto_min, rack_rto_max, rack->r_ctl.timer_slop); } if ((th->th_ack == tp->snd_una) && (tiwin == tp->snd_wnd) && ((to->to_flags & TOF_SACK) == 0)) { rack_strike_dupack(rack); dup_ack_struck = 1; } rack_log_ack(tp, to, th, ((in_rec == 0) && IN_FASTRECOVERY(tp->t_flags)), dup_ack_struck, &dsack_seen, &sacks_seen); if ((rack->sack_attack_disable > 0) && (th->th_ack == tp->snd_una) && (tiwin == tp->snd_wnd) && (dsack_seen == 0) && (sacks_seen > 0)) { /* * If sacks have been disabled we may * want to strike a dup-ack "ignoring" the * sack as long as the sack was not a "dsack". Note * that if no sack is sent (TOF_SACK is off) then the * normal dsack code above rack_log_ack() would have * already struck. So this is just to catch the case * were we are ignoring sacks from this guy due to * it being a suspected attacker. */ rack_strike_dupack(rack); } } if (__predict_false(SEQ_LEQ(th->th_ack, tp->snd_una))) { /* * Old ack, behind (or duplicate to) the last one rcv'd * Note: We mark reordering is occuring if its * less than and we have not closed our window. */ if (SEQ_LT(th->th_ack, tp->snd_una) && (sbspace(&so->so_rcv) > ctf_fixed_maxseg(tp))) { rack->r_ctl.rc_reorder_ts = tcp_tv_to_usectick(&rack->r_ctl.act_rcv_time); if (rack->r_ctl.rc_reorder_ts == 0) rack->r_ctl.rc_reorder_ts = 1; } return (0); } /* * If we reach this point, ACK is not a duplicate, i.e., it ACKs * something we sent. */ if (tp->t_flags & TF_NEEDSYN) { /* * T/TCP: Connection was half-synchronized, and our SYN has * been ACK'd (so connection is now fully synchronized). Go * to non-starred state, increment snd_una for ACK of SYN, * and check if we can do window scaling. */ tp->t_flags &= ~TF_NEEDSYN; tp->snd_una++; /* Do window scaling? */ if ((tp->t_flags & (TF_RCVD_SCALE | TF_REQ_SCALE)) == (TF_RCVD_SCALE | TF_REQ_SCALE)) { tp->rcv_scale = tp->request_r_scale; /* Send window already scaled. */ } } nsegs = max(1, m->m_pkthdr.lro_nsegs); acked = BYTES_THIS_ACK(tp, th); if (acked) { /* * Any time we move the cum-ack forward clear * keep-alive tied probe-not-answered. The * persists clears its own on entry. */ rack->probe_not_answered = 0; } KMOD_TCPSTAT_ADD(tcps_rcvackpack, nsegs); KMOD_TCPSTAT_ADD(tcps_rcvackbyte, acked); /* * If we just performed our first retransmit, and the ACK arrives * within our recovery window, then it was a mistake to do the * retransmit in the first place. Recover our original cwnd and * ssthresh, and proceed to transmit where we left off. */ if ((tp->t_flags & TF_PREVVALID) && ((tp->t_flags & TF_RCVD_TSTMP) == 0)) { tp->t_flags &= ~TF_PREVVALID; if (tp->t_rxtshift == 1 && (int)(ticks - tp->t_badrxtwin) < 0) rack_cong_signal(tp, CC_RTO_ERR, th->th_ack, __LINE__); } if (acked) { /* assure we are not backed off */ tp->t_rxtshift = 0; RACK_TCPT_RANGESET(tp->t_rxtcur, RACK_REXMTVAL(tp), rack_rto_min, rack_rto_max, rack->r_ctl.timer_slop); rack->rc_tlp_in_progress = 0; rack->r_ctl.rc_tlp_cnt_out = 0; /* * If it is the RXT timer we want to * stop it, so we can restart a TLP. */ if (rack->r_ctl.rc_hpts_flags & PACE_TMR_RXT) rack_timer_cancel(tp, rack, rack->r_ctl.rc_rcvtime, __LINE__); #ifdef TCP_REQUEST_TRK rack_req_check_for_comp(rack, th->th_ack); #endif } /* * If we have a timestamp reply, update smoothed round trip time. If * no timestamp is present but transmit timer is running and timed * sequence number was acked, update smoothed round trip time. Since * we now have an rtt measurement, cancel the timer backoff (cf., * Phil Karn's retransmit alg.). Recompute the initial retransmit * timer. * * Some boxes send broken timestamp replies during the SYN+ACK * phase, ignore timestamps of 0 or we could calculate a huge RTT * and blow up the retransmit timer. */ /* * If all outstanding data is acked, stop retransmit timer and * remember to restart (more output or persist). If there is more * data to be acked, restart retransmit timer, using current * (possibly backed-off) value. */ if (acked == 0) { if (ofia) *ofia = ourfinisacked; return (0); } if (IN_RECOVERY(tp->t_flags)) { if (SEQ_LT(th->th_ack, tp->snd_recover) && (SEQ_LT(th->th_ack, tp->snd_max))) { tcp_rack_partialack(tp); } else { rack_post_recovery(tp, th->th_ack); recovery = 1; } } /* * Let the congestion control algorithm update congestion control * related information. This typically means increasing the * congestion window. */ rack_ack_received(tp, rack, th->th_ack, nsegs, CC_ACK, recovery); SOCKBUF_LOCK(&so->so_snd); acked_amount = min(acked, (int)sbavail(&so->so_snd)); tp->snd_wnd -= acked_amount; mfree = sbcut_locked(&so->so_snd, acked_amount); if ((sbused(&so->so_snd) == 0) && (acked > acked_amount) && (tp->t_state >= TCPS_FIN_WAIT_1) && (tp->t_flags & TF_SENTFIN)) { /* * We must be sure our fin * was sent and acked (we can be * in FIN_WAIT_1 without having * sent the fin). */ ourfinisacked = 1; } tp->snd_una = th->th_ack; /* wakeups? */ if (acked_amount && sbavail(&so->so_snd)) rack_adjust_sendmap_head(rack, &so->so_snd); rack_log_wakeup(tp,rack, &so->so_snd, acked, 2); /* NB: sowwakeup_locked() does an implicit unlock. */ sowwakeup_locked(so); /* now check the rxt clamps */ if ((recovery == 1) && (rack->excess_rxt_on) && (rack->r_cwnd_was_clamped == 0)) { do_rack_excess_rxt(tp, rack); } else if (rack->r_cwnd_was_clamped) do_rack_check_for_unclamp(tp, rack); m_freem(mfree); if (SEQ_GT(tp->snd_una, tp->snd_recover)) tp->snd_recover = tp->snd_una; if (SEQ_LT(tp->snd_nxt, tp->snd_una)) { tp->snd_nxt = tp->snd_una; } if (under_pacing && (rack->use_fixed_rate == 0) && (rack->in_probe_rtt == 0) && rack->rc_gp_dyn_mul && rack->rc_always_pace) { /* Check if we are dragging bottom */ rack_check_bottom_drag(tp, rack, so); } if (tp->snd_una == tp->snd_max) { /* Nothing left outstanding */ tp->t_flags &= ~TF_PREVVALID; rack->r_ctl.rc_went_idle_time = tcp_get_usecs(NULL); rack->r_ctl.retran_during_recovery = 0; rack->r_ctl.dsack_byte_cnt = 0; if (rack->r_ctl.rc_went_idle_time == 0) rack->r_ctl.rc_went_idle_time = 1; rack_log_progress_event(rack, tp, 0, PROGRESS_CLEAR, __LINE__); if (sbavail(&tptosocket(tp)->so_snd) == 0) tp->t_acktime = 0; rack_timer_cancel(tp, rack, rack->r_ctl.rc_rcvtime, __LINE__); rack->rc_suspicious = 0; /* Set need output so persist might get set */ rack->r_wanted_output = 1; sack_filter_clear(&rack->r_ctl.rack_sf, tp->snd_una); if ((tp->t_state >= TCPS_FIN_WAIT_1) && (sbavail(&so->so_snd) == 0) && (tp->t_flags2 & TF2_DROP_AF_DATA)) { /* * The socket was gone and the * peer sent data (now or in the past), time to * reset him. */ *ret_val = 1; /* tcp_close will kill the inp pre-log the Reset */ tcp_log_end_status(tp, TCP_EI_STATUS_SERVER_RST); tp = tcp_close(tp); ctf_do_dropwithreset(m, tp, th, BANDLIM_UNLIMITED, tlen); return (1); } } if (ofia) *ofia = ourfinisacked; return (0); } static void rack_log_collapse(struct tcp_rack *rack, uint32_t cnt, uint32_t split, uint32_t out, int line, int dir, uint32_t flags, struct rack_sendmap *rsm) { if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log, 0, sizeof(log)); log.u_bbr.flex1 = cnt; log.u_bbr.flex2 = split; log.u_bbr.flex3 = out; log.u_bbr.flex4 = line; log.u_bbr.flex5 = rack->r_must_retran; log.u_bbr.flex6 = flags; log.u_bbr.flex7 = rack->rc_has_collapsed; log.u_bbr.flex8 = dir; /* * 1 is collapsed, 0 is uncollapsed, * 2 is log of a rsm being marked, 3 is a split. */ if (rsm == NULL) log.u_bbr.rttProp = 0; else log.u_bbr.rttProp = (uint64_t)rsm; log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, TCP_RACK_LOG_COLLAPSE, 0, 0, &log, false, &tv); } } static void rack_collapsed_window(struct tcp_rack *rack, uint32_t out, tcp_seq th_ack, int line) { /* * Here all we do is mark the collapsed point and set the flag. * This may happen again and again, but there is no * sense splitting our map until we know where the * peer finally lands in the collapse. */ tcp_trace_point(rack->rc_tp, TCP_TP_COLLAPSED_WND); if ((rack->rc_has_collapsed == 0) || (rack->r_ctl.last_collapse_point != (th_ack + rack->rc_tp->snd_wnd))) counter_u64_add(rack_collapsed_win_seen, 1); rack->r_ctl.last_collapse_point = th_ack + rack->rc_tp->snd_wnd; rack->r_ctl.high_collapse_point = rack->rc_tp->snd_max; rack->rc_has_collapsed = 1; rack->r_collapse_point_valid = 1; rack_log_collapse(rack, 0, th_ack, rack->r_ctl.last_collapse_point, line, 1, 0, NULL); } static void rack_un_collapse_window(struct tcp_rack *rack, int line) { struct rack_sendmap *nrsm, *rsm; int cnt = 0, split = 0; int insret __diagused; tcp_trace_point(rack->rc_tp, TCP_TP_COLLAPSED_WND); rack->rc_has_collapsed = 0; rsm = tqhash_find(rack->r_ctl.tqh, rack->r_ctl.last_collapse_point); if (rsm == NULL) { /* Nothing to do maybe the peer ack'ed it all */ rack_log_collapse(rack, 0, 0, ctf_outstanding(rack->rc_tp), line, 0, 0, NULL); return; } /* Now do we need to split this one? */ if (SEQ_GT(rack->r_ctl.last_collapse_point, rsm->r_start)) { rack_log_collapse(rack, rsm->r_start, rsm->r_end, rack->r_ctl.last_collapse_point, line, 3, rsm->r_flags, rsm); nrsm = rack_alloc_limit(rack, RACK_LIMIT_TYPE_SPLIT); if (nrsm == NULL) { /* We can't get a rsm, mark all? */ nrsm = rsm; goto no_split; } /* Clone it */ split = 1; rack_clone_rsm(rack, nrsm, rsm, rack->r_ctl.last_collapse_point); #ifndef INVARIANTS (void)tqhash_insert(rack->r_ctl.tqh, nrsm); #else if ((insret = tqhash_insert(rack->r_ctl.tqh, nrsm)) != 0) { panic("Insert in rb tree of %p fails ret:%d rack:%p rsm:%p", nrsm, insret, rack, rsm); } #endif rack_log_map_chg(rack->rc_tp, rack, NULL, rsm, nrsm, MAP_SPLIT, rack->r_ctl.last_collapse_point, __LINE__); if (rsm->r_in_tmap) { TAILQ_INSERT_AFTER(&rack->r_ctl.rc_tmap, rsm, nrsm, r_tnext); nrsm->r_in_tmap = 1; } /* * Set in the new RSM as the * collapsed starting point */ rsm = nrsm; } no_split: TQHASH_FOREACH_FROM(nrsm, rack->r_ctl.tqh, rsm) { cnt++; nrsm->r_flags |= RACK_RWND_COLLAPSED; rack_log_collapse(rack, nrsm->r_start, nrsm->r_end, 0, line, 4, nrsm->r_flags, nrsm); cnt++; } if (cnt) { counter_u64_add(rack_collapsed_win, 1); } rack_log_collapse(rack, cnt, split, ctf_outstanding(rack->rc_tp), line, 0, 0, NULL); } static void rack_handle_delayed_ack(struct tcpcb *tp, struct tcp_rack *rack, int32_t tlen, int32_t tfo_syn) { if (DELAY_ACK(tp, tlen) || tfo_syn) { rack_timer_cancel(tp, rack, rack->r_ctl.rc_rcvtime, __LINE__); tp->t_flags |= TF_DELACK; } else { rack->r_wanted_output = 1; tp->t_flags |= TF_ACKNOW; } } static void rack_validate_fo_sendwin_up(struct tcpcb *tp, struct tcp_rack *rack) { /* * If fast output is in progress, lets validate that * the new window did not shrink on us and make it * so fast output should end. */ if (rack->r_fast_output) { uint32_t out; /* * Calculate what we will send if left as is * and compare that to our send window. */ out = ctf_outstanding(tp); if ((out + rack->r_ctl.fsb.left_to_send) > tp->snd_wnd) { /* ok we have an issue */ if (out >= tp->snd_wnd) { /* Turn off fast output the window is met or collapsed */ rack->r_fast_output = 0; } else { /* we have some room left */ rack->r_ctl.fsb.left_to_send = tp->snd_wnd - out; if (rack->r_ctl.fsb.left_to_send < ctf_fixed_maxseg(tp)) { /* If not at least 1 full segment never mind */ rack->r_fast_output = 0; } } } } } /* * Return value of 1, the TCB is unlocked and most * likely gone, return value of 0, the TCP is still * locked. */ static int rack_process_data(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, int32_t drop_hdrlen, int32_t tlen, uint32_t tiwin, int32_t thflags, int32_t nxt_pkt) { /* * Update window information. Don't look at window if no ACK: TAC's * send garbage on first SYN. */ int32_t nsegs; int32_t tfo_syn; struct tcp_rack *rack; INP_WLOCK_ASSERT(tptoinpcb(tp)); rack = (struct tcp_rack *)tp->t_fb_ptr; nsegs = max(1, m->m_pkthdr.lro_nsegs); if ((thflags & TH_ACK) && (SEQ_LT(tp->snd_wl1, th->th_seq) || (tp->snd_wl1 == th->th_seq && (SEQ_LT(tp->snd_wl2, th->th_ack) || (tp->snd_wl2 == th->th_ack && tiwin > tp->snd_wnd))))) { /* keep track of pure window updates */ if (tlen == 0 && tp->snd_wl2 == th->th_ack && tiwin > tp->snd_wnd) KMOD_TCPSTAT_INC(tcps_rcvwinupd); tp->snd_wnd = tiwin; rack_validate_fo_sendwin_up(tp, rack); tp->snd_wl1 = th->th_seq; tp->snd_wl2 = th->th_ack; if (tp->snd_wnd > tp->max_sndwnd) tp->max_sndwnd = tp->snd_wnd; rack->r_wanted_output = 1; } else if (thflags & TH_ACK) { if ((tp->snd_wl2 == th->th_ack) && (tiwin < tp->snd_wnd)) { tp->snd_wnd = tiwin; rack_validate_fo_sendwin_up(tp, rack); tp->snd_wl1 = th->th_seq; tp->snd_wl2 = th->th_ack; } } if (tp->snd_wnd < ctf_outstanding(tp)) /* The peer collapsed the window */ rack_collapsed_window(rack, ctf_outstanding(tp), th->th_ack, __LINE__); else if (rack->rc_has_collapsed) rack_un_collapse_window(rack, __LINE__); if ((rack->r_collapse_point_valid) && (SEQ_GT(th->th_ack, rack->r_ctl.high_collapse_point))) rack->r_collapse_point_valid = 0; /* Was persist timer active and now we have window space? */ if ((rack->rc_in_persist != 0) && (tp->snd_wnd >= min((rack->r_ctl.rc_high_rwnd/2), rack->r_ctl.rc_pace_min_segs))) { rack_exit_persist(tp, rack, rack->r_ctl.rc_rcvtime); tp->snd_nxt = tp->snd_max; /* Make sure we output to start the timer */ rack->r_wanted_output = 1; } /* Do we enter persists? */ if ((rack->rc_in_persist == 0) && (tp->snd_wnd < min((rack->r_ctl.rc_high_rwnd/2), rack->r_ctl.rc_pace_min_segs)) && TCPS_HAVEESTABLISHED(tp->t_state) && ((tp->snd_max == tp->snd_una) || rack->rc_has_collapsed) && sbavail(&tptosocket(tp)->so_snd) && (sbavail(&tptosocket(tp)->so_snd) > tp->snd_wnd)) { /* * Here the rwnd is less than * the pacing size, we are established, * nothing is outstanding, and there is * data to send. Enter persists. */ rack_enter_persist(tp, rack, rack->r_ctl.rc_rcvtime, tp->snd_una); } if (tp->t_flags2 & TF2_DROP_AF_DATA) { m_freem(m); return (0); } /* * don't process the URG bit, ignore them drag * along the up. */ tp->rcv_up = tp->rcv_nxt; /* * Process the segment text, merging it into the TCP sequencing * queue, and arranging for acknowledgment of receipt if necessary. * This process logically involves adjusting tp->rcv_wnd as data is * presented to the user (this happens in tcp_usrreq.c, case * PRU_RCVD). If a FIN has already been received on this connection * then we just ignore the text. */ tfo_syn = ((tp->t_state == TCPS_SYN_RECEIVED) && IS_FASTOPEN(tp->t_flags)); if ((tlen || (thflags & TH_FIN) || (tfo_syn && tlen > 0)) && TCPS_HAVERCVDFIN(tp->t_state) == 0) { tcp_seq save_start = th->th_seq; tcp_seq save_rnxt = tp->rcv_nxt; int save_tlen = tlen; m_adj(m, drop_hdrlen); /* delayed header drop */ /* * Insert segment which includes th into TCP reassembly * queue with control block tp. Set thflags to whether * reassembly now includes a segment with FIN. This handles * the common case inline (segment is the next to be * received on an established connection, and the queue is * empty), avoiding linkage into and removal from the queue * and repetition of various conversions. Set DELACK for * segments received in order, but ack immediately when * segments are out of order (so fast retransmit can work). */ if (th->th_seq == tp->rcv_nxt && SEGQ_EMPTY(tp) && (TCPS_HAVEESTABLISHED(tp->t_state) || tfo_syn)) { #ifdef NETFLIX_SB_LIMITS u_int mcnt, appended; if (so->so_rcv.sb_shlim) { mcnt = m_memcnt(m); appended = 0; if (counter_fo_get(so->so_rcv.sb_shlim, mcnt, CFO_NOSLEEP, NULL) == false) { counter_u64_add(tcp_sb_shlim_fails, 1); m_freem(m); return (0); } } #endif rack_handle_delayed_ack(tp, rack, tlen, tfo_syn); tp->rcv_nxt += tlen; if (tlen && ((tp->t_flags2 & TF2_FBYTES_COMPLETE) == 0) && (tp->t_fbyte_in == 0)) { tp->t_fbyte_in = ticks; if (tp->t_fbyte_in == 0) tp->t_fbyte_in = 1; if (tp->t_fbyte_out && tp->t_fbyte_in) tp->t_flags2 |= TF2_FBYTES_COMPLETE; } thflags = tcp_get_flags(th) & TH_FIN; KMOD_TCPSTAT_ADD(tcps_rcvpack, nsegs); KMOD_TCPSTAT_ADD(tcps_rcvbyte, tlen); SOCKBUF_LOCK(&so->so_rcv); if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { m_freem(m); } else #ifdef NETFLIX_SB_LIMITS appended = #endif sbappendstream_locked(&so->so_rcv, m, 0); rack_log_wakeup(tp,rack, &so->so_rcv, tlen, 1); /* NB: sorwakeup_locked() does an implicit unlock. */ sorwakeup_locked(so); #ifdef NETFLIX_SB_LIMITS if (so->so_rcv.sb_shlim && appended != mcnt) counter_fo_release(so->so_rcv.sb_shlim, mcnt - appended); #endif } else { /* * XXX: Due to the header drop above "th" is * theoretically invalid by now. Fortunately * m_adj() doesn't actually frees any mbufs when * trimming from the head. */ tcp_seq temp = save_start; thflags = tcp_reass(tp, th, &temp, &tlen, m); tp->t_flags |= TF_ACKNOW; if (tp->t_flags & TF_WAKESOR) { tp->t_flags &= ~TF_WAKESOR; /* NB: sorwakeup_locked() does an implicit unlock. */ sorwakeup_locked(so); } } if ((tp->t_flags & TF_SACK_PERMIT) && (save_tlen > 0) && TCPS_HAVEESTABLISHED(tp->t_state)) { if ((tlen == 0) && (SEQ_LT(save_start, save_rnxt))) { /* * DSACK actually handled in the fastpath * above. */ tcp_update_sack_list(tp, save_start, save_start + save_tlen); } else if ((tlen > 0) && SEQ_GT(tp->rcv_nxt, save_rnxt)) { if ((tp->rcv_numsacks >= 1) && (tp->sackblks[0].end == save_start)) { /* * Partial overlap, recorded at todrop * above. */ tcp_update_sack_list(tp, tp->sackblks[0].start, tp->sackblks[0].end); } else { tcp_update_dsack_list(tp, save_start, save_start + save_tlen); } } else if (tlen >= save_tlen) { /* Update of sackblks. */ tcp_update_dsack_list(tp, save_start, save_start + save_tlen); } else if (tlen > 0) { tcp_update_dsack_list(tp, save_start, save_start + tlen); } } } else { m_freem(m); thflags &= ~TH_FIN; } /* * If FIN is received ACK the FIN and let the user know that the * connection is closing. */ if (thflags & TH_FIN) { if (TCPS_HAVERCVDFIN(tp->t_state) == 0) { /* The socket upcall is handled by socantrcvmore. */ socantrcvmore(so); /* * If connection is half-synchronized (ie NEEDSYN * flag on) then delay ACK, so it may be piggybacked * when SYN is sent. Otherwise, since we received a * FIN then no more input can be expected, send ACK * now. */ if (tp->t_flags & TF_NEEDSYN) { rack_timer_cancel(tp, rack, rack->r_ctl.rc_rcvtime, __LINE__); tp->t_flags |= TF_DELACK; } else { tp->t_flags |= TF_ACKNOW; } tp->rcv_nxt++; } switch (tp->t_state) { /* * In SYN_RECEIVED and ESTABLISHED STATES enter the * CLOSE_WAIT state. */ case TCPS_SYN_RECEIVED: tp->t_starttime = ticks; /* FALLTHROUGH */ case TCPS_ESTABLISHED: rack_timer_cancel(tp, rack, rack->r_ctl.rc_rcvtime, __LINE__); tcp_state_change(tp, TCPS_CLOSE_WAIT); break; /* * If still in FIN_WAIT_1 STATE FIN has not been * acked so enter the CLOSING state. */ case TCPS_FIN_WAIT_1: rack_timer_cancel(tp, rack, rack->r_ctl.rc_rcvtime, __LINE__); tcp_state_change(tp, TCPS_CLOSING); break; /* * In FIN_WAIT_2 state enter the TIME_WAIT state, * starting the time-wait timer, turning off the * other standard timers. */ case TCPS_FIN_WAIT_2: rack_timer_cancel(tp, rack, rack->r_ctl.rc_rcvtime, __LINE__); tcp_twstart(tp); return (1); } } /* * Return any desired output. */ if ((tp->t_flags & TF_ACKNOW) || (sbavail(&so->so_snd) > (tp->snd_max - tp->snd_una))) { rack->r_wanted_output = 1; } return (0); } /* * Here nothing is really faster, its just that we * have broken out the fast-data path also just like * the fast-ack. */ static int rack_do_fastnewdata(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, uint32_t tiwin, int32_t nxt_pkt, uint8_t iptos) { int32_t nsegs; int32_t newsize = 0; /* automatic sockbuf scaling */ struct tcp_rack *rack; #ifdef NETFLIX_SB_LIMITS u_int mcnt, appended; #endif /* * If last ACK falls within this segment's sequence numbers, record * the timestamp. NOTE that the test is modified according to the * latest proposal of the tcplw@cray.com list (Braden 1993/04/26). */ if (__predict_false(th->th_seq != tp->rcv_nxt)) { return (0); } if (__predict_false(tp->snd_nxt != tp->snd_max)) { return (0); } if (tiwin && tiwin != tp->snd_wnd) { return (0); } if (__predict_false((tp->t_flags & (TF_NEEDSYN | TF_NEEDFIN)))) { return (0); } if (__predict_false((to->to_flags & TOF_TS) && (TSTMP_LT(to->to_tsval, tp->ts_recent)))) { return (0); } if (__predict_false((th->th_ack != tp->snd_una))) { return (0); } if (__predict_false(tlen > sbspace(&so->so_rcv))) { return (0); } if ((to->to_flags & TOF_TS) != 0 && SEQ_LEQ(th->th_seq, tp->last_ack_sent)) { tp->ts_recent_age = tcp_ts_getticks(); tp->ts_recent = to->to_tsval; } rack = (struct tcp_rack *)tp->t_fb_ptr; /* * This is a pure, in-sequence data packet with nothing on the * reassembly queue and we have enough buffer space to take it. */ nsegs = max(1, m->m_pkthdr.lro_nsegs); #ifdef NETFLIX_SB_LIMITS if (so->so_rcv.sb_shlim) { mcnt = m_memcnt(m); appended = 0; if (counter_fo_get(so->so_rcv.sb_shlim, mcnt, CFO_NOSLEEP, NULL) == false) { counter_u64_add(tcp_sb_shlim_fails, 1); m_freem(m); return (1); } } #endif /* Clean receiver SACK report if present */ if (tp->rcv_numsacks) tcp_clean_sackreport(tp); KMOD_TCPSTAT_INC(tcps_preddat); tp->rcv_nxt += tlen; if (tlen && ((tp->t_flags2 & TF2_FBYTES_COMPLETE) == 0) && (tp->t_fbyte_in == 0)) { tp->t_fbyte_in = ticks; if (tp->t_fbyte_in == 0) tp->t_fbyte_in = 1; if (tp->t_fbyte_out && tp->t_fbyte_in) tp->t_flags2 |= TF2_FBYTES_COMPLETE; } /* * Pull snd_wl1 up to prevent seq wrap relative to th_seq. */ tp->snd_wl1 = th->th_seq; /* * Pull rcv_up up to prevent seq wrap relative to rcv_nxt. */ tp->rcv_up = tp->rcv_nxt; KMOD_TCPSTAT_ADD(tcps_rcvpack, nsegs); KMOD_TCPSTAT_ADD(tcps_rcvbyte, tlen); newsize = tcp_autorcvbuf(m, th, so, tp, tlen); /* Add data to socket buffer. */ SOCKBUF_LOCK(&so->so_rcv); if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { m_freem(m); } else { /* * Set new socket buffer size. Give up when limit is * reached. */ if (newsize) if (!sbreserve_locked(so, SO_RCV, newsize, NULL)) so->so_rcv.sb_flags &= ~SB_AUTOSIZE; m_adj(m, drop_hdrlen); /* delayed header drop */ #ifdef NETFLIX_SB_LIMITS appended = #endif sbappendstream_locked(&so->so_rcv, m, 0); ctf_calc_rwin(so, tp); } rack_log_wakeup(tp,rack, &so->so_rcv, tlen, 1); /* NB: sorwakeup_locked() does an implicit unlock. */ sorwakeup_locked(so); #ifdef NETFLIX_SB_LIMITS if (so->so_rcv.sb_shlim && mcnt != appended) counter_fo_release(so->so_rcv.sb_shlim, mcnt - appended); #endif rack_handle_delayed_ack(tp, rack, tlen, 0); if (tp->snd_una == tp->snd_max) sack_filter_clear(&rack->r_ctl.rack_sf, tp->snd_una); return (1); } /* * This subfunction is used to try to highly optimize the * fast path. We again allow window updates that are * in sequence to remain in the fast-path. We also add * in the __predict's to attempt to help the compiler. * Note that if we return a 0, then we can *not* process * it and the caller should push the packet into the * slow-path. */ static int rack_fastack(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, uint32_t tiwin, int32_t nxt_pkt, uint32_t cts) { int32_t acked; int32_t nsegs; int32_t under_pacing = 0; struct tcp_rack *rack; if (__predict_false(SEQ_LEQ(th->th_ack, tp->snd_una))) { /* Old ack, behind (or duplicate to) the last one rcv'd */ return (0); } if (__predict_false(SEQ_GT(th->th_ack, tp->snd_max))) { /* Above what we have sent? */ return (0); } if (__predict_false(tp->snd_nxt != tp->snd_max)) { /* We are retransmitting */ return (0); } if (__predict_false(tiwin == 0)) { /* zero window */ return (0); } if (__predict_false(tp->t_flags & (TF_NEEDSYN | TF_NEEDFIN))) { /* We need a SYN or a FIN, unlikely.. */ return (0); } if ((to->to_flags & TOF_TS) && __predict_false(TSTMP_LT(to->to_tsval, tp->ts_recent))) { /* Timestamp is behind .. old ack with seq wrap? */ return (0); } if (__predict_false(IN_RECOVERY(tp->t_flags))) { /* Still recovering */ return (0); } rack = (struct tcp_rack *)tp->t_fb_ptr; if (rack->r_ctl.rc_sacked) { /* We have sack holes on our scoreboard */ return (0); } /* Ok if we reach here, we can process a fast-ack */ if (rack->gp_ready && (rack->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT)) { under_pacing = 1; } nsegs = max(1, m->m_pkthdr.lro_nsegs); rack_log_ack(tp, to, th, 0, 0, NULL, NULL); /* Did the window get updated? */ if (tiwin != tp->snd_wnd) { tp->snd_wnd = tiwin; rack_validate_fo_sendwin_up(tp, rack); tp->snd_wl1 = th->th_seq; if (tp->snd_wnd > tp->max_sndwnd) tp->max_sndwnd = tp->snd_wnd; } /* Do we exit persists? */ if ((rack->rc_in_persist != 0) && (tp->snd_wnd >= min((rack->r_ctl.rc_high_rwnd/2), rack->r_ctl.rc_pace_min_segs))) { rack_exit_persist(tp, rack, cts); } /* Do we enter persists? */ if ((rack->rc_in_persist == 0) && (tp->snd_wnd < min((rack->r_ctl.rc_high_rwnd/2), rack->r_ctl.rc_pace_min_segs)) && TCPS_HAVEESTABLISHED(tp->t_state) && ((tp->snd_max == tp->snd_una) || rack->rc_has_collapsed) && sbavail(&tptosocket(tp)->so_snd) && (sbavail(&tptosocket(tp)->so_snd) > tp->snd_wnd)) { /* * Here the rwnd is less than * the pacing size, we are established, * nothing is outstanding, and there is * data to send. Enter persists. */ rack_enter_persist(tp, rack, rack->r_ctl.rc_rcvtime, th->th_ack); } /* * If last ACK falls within this segment's sequence numbers, record * the timestamp. NOTE that the test is modified according to the * latest proposal of the tcplw@cray.com list (Braden 1993/04/26). */ if ((to->to_flags & TOF_TS) != 0 && SEQ_LEQ(th->th_seq, tp->last_ack_sent)) { tp->ts_recent_age = tcp_ts_getticks(); tp->ts_recent = to->to_tsval; } /* * This is a pure ack for outstanding data. */ KMOD_TCPSTAT_INC(tcps_predack); /* * "bad retransmit" recovery. */ if ((tp->t_flags & TF_PREVVALID) && ((tp->t_flags & TF_RCVD_TSTMP) == 0)) { tp->t_flags &= ~TF_PREVVALID; if (tp->t_rxtshift == 1 && (int)(ticks - tp->t_badrxtwin) < 0) rack_cong_signal(tp, CC_RTO_ERR, th->th_ack, __LINE__); } /* * Recalculate the transmit timer / rtt. * * Some boxes send broken timestamp replies during the SYN+ACK * phase, ignore timestamps of 0 or we could calculate a huge RTT * and blow up the retransmit timer. */ acked = BYTES_THIS_ACK(tp, th); #ifdef TCP_HHOOK /* Run HHOOK_TCP_ESTABLISHED_IN helper hooks. */ hhook_run_tcp_est_in(tp, th, to); #endif KMOD_TCPSTAT_ADD(tcps_rcvackpack, nsegs); KMOD_TCPSTAT_ADD(tcps_rcvackbyte, acked); if (acked) { struct mbuf *mfree; rack_ack_received(tp, rack, th->th_ack, nsegs, CC_ACK, 0); SOCKBUF_LOCK(&so->so_snd); mfree = sbcut_locked(&so->so_snd, acked); tp->snd_una = th->th_ack; /* Note we want to hold the sb lock through the sendmap adjust */ rack_adjust_sendmap_head(rack, &so->so_snd); /* Wake up the socket if we have room to write more */ rack_log_wakeup(tp,rack, &so->so_snd, acked, 2); sowwakeup_locked(so); m_freem(mfree); tp->t_rxtshift = 0; RACK_TCPT_RANGESET(tp->t_rxtcur, RACK_REXMTVAL(tp), rack_rto_min, rack_rto_max, rack->r_ctl.timer_slop); rack->rc_tlp_in_progress = 0; rack->r_ctl.rc_tlp_cnt_out = 0; /* * If it is the RXT timer we want to * stop it, so we can restart a TLP. */ if (rack->r_ctl.rc_hpts_flags & PACE_TMR_RXT) rack_timer_cancel(tp, rack, rack->r_ctl.rc_rcvtime, __LINE__); #ifdef TCP_REQUEST_TRK rack_req_check_for_comp(rack, th->th_ack); #endif } /* * Let the congestion control algorithm update congestion control * related information. This typically means increasing the * congestion window. */ if (tp->snd_wnd < ctf_outstanding(tp)) { /* The peer collapsed the window */ rack_collapsed_window(rack, ctf_outstanding(tp), th->th_ack, __LINE__); } else if (rack->rc_has_collapsed) rack_un_collapse_window(rack, __LINE__); if ((rack->r_collapse_point_valid) && (SEQ_GT(tp->snd_una, rack->r_ctl.high_collapse_point))) rack->r_collapse_point_valid = 0; /* * Pull snd_wl2 up to prevent seq wrap relative to th_ack. */ tp->snd_wl2 = th->th_ack; tp->t_dupacks = 0; m_freem(m); /* ND6_HINT(tp); *//* Some progress has been made. */ /* * If all outstanding data are acked, stop retransmit timer, * otherwise restart timer using current (possibly backed-off) * value. If process is waiting for space, wakeup/selwakeup/signal. * If data are ready to send, let tcp_output decide between more * output or persist. */ if (under_pacing && (rack->use_fixed_rate == 0) && (rack->in_probe_rtt == 0) && rack->rc_gp_dyn_mul && rack->rc_always_pace) { /* Check if we are dragging bottom */ rack_check_bottom_drag(tp, rack, so); } if (tp->snd_una == tp->snd_max) { tp->t_flags &= ~TF_PREVVALID; rack->r_ctl.retran_during_recovery = 0; rack->rc_suspicious = 0; rack->r_ctl.dsack_byte_cnt = 0; rack->r_ctl.rc_went_idle_time = tcp_get_usecs(NULL); if (rack->r_ctl.rc_went_idle_time == 0) rack->r_ctl.rc_went_idle_time = 1; rack_log_progress_event(rack, tp, 0, PROGRESS_CLEAR, __LINE__); if (sbavail(&tptosocket(tp)->so_snd) == 0) tp->t_acktime = 0; rack_timer_cancel(tp, rack, rack->r_ctl.rc_rcvtime, __LINE__); } if (acked && rack->r_fast_output) rack_gain_for_fastoutput(rack, tp, so, (uint32_t)acked); if (sbavail(&so->so_snd)) { rack->r_wanted_output = 1; } return (1); } /* * Return value of 1, the TCB is unlocked and most * likely gone, return value of 0, the TCP is still * locked. */ static int rack_do_syn_sent(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos) { int32_t ret_val = 0; int32_t todrop; int32_t ourfinisacked = 0; struct tcp_rack *rack; INP_WLOCK_ASSERT(tptoinpcb(tp)); ctf_calc_rwin(so, tp); /* * If the state is SYN_SENT: if seg contains an ACK, but not for our * SYN, drop the input. if seg contains a RST, then drop the * connection. if seg does not contain SYN, then drop it. Otherwise * this is an acceptable SYN segment initialize tp->rcv_nxt and * tp->irs if seg contains ack then advance tp->snd_una if seg * contains an ECE and ECN support is enabled, the stream is ECN * capable. if SYN has been acked change to ESTABLISHED else * SYN_RCVD state arrange for segment to be acked (eventually) * continue processing rest of data/controls. */ if ((thflags & TH_ACK) && (SEQ_LEQ(th->th_ack, tp->iss) || SEQ_GT(th->th_ack, tp->snd_max))) { tcp_log_end_status(tp, TCP_EI_STATUS_RST_IN_FRONT); ctf_do_dropwithreset(m, tp, th, BANDLIM_RST_OPENPORT, tlen); return (1); } if ((thflags & (TH_ACK | TH_RST)) == (TH_ACK | TH_RST)) { TCP_PROBE5(connect__refused, NULL, tp, mtod(m, const char *), tp, th); tp = tcp_drop(tp, ECONNREFUSED); ctf_do_drop(m, tp); return (1); } if (thflags & TH_RST) { ctf_do_drop(m, tp); return (1); } if (!(thflags & TH_SYN)) { ctf_do_drop(m, tp); return (1); } tp->irs = th->th_seq; tcp_rcvseqinit(tp); rack = (struct tcp_rack *)tp->t_fb_ptr; if (thflags & TH_ACK) { int tfo_partial = 0; KMOD_TCPSTAT_INC(tcps_connects); soisconnected(so); #ifdef MAC mac_socketpeer_set_from_mbuf(m, so); #endif /* Do window scaling on this connection? */ if ((tp->t_flags & (TF_RCVD_SCALE | TF_REQ_SCALE)) == (TF_RCVD_SCALE | TF_REQ_SCALE)) { tp->rcv_scale = tp->request_r_scale; } tp->rcv_adv += min(tp->rcv_wnd, TCP_MAXWIN << tp->rcv_scale); /* * If not all the data that was sent in the TFO SYN * has been acked, resend the remainder right away. */ if (IS_FASTOPEN(tp->t_flags) && (tp->snd_una != tp->snd_max)) { tp->snd_nxt = th->th_ack; tfo_partial = 1; } /* * If there's data, delay ACK; if there's also a FIN ACKNOW * will be turned on later. */ if (DELAY_ACK(tp, tlen) && tlen != 0 && !tfo_partial) { rack_timer_cancel(tp, rack, rack->r_ctl.rc_rcvtime, __LINE__); tp->t_flags |= TF_DELACK; } else { rack->r_wanted_output = 1; tp->t_flags |= TF_ACKNOW; } tcp_ecn_input_syn_sent(tp, thflags, iptos); if (SEQ_GT(th->th_ack, tp->snd_una)) { /* * We advance snd_una for the * fast open case. If th_ack is * acknowledging data beyond * snd_una we can't just call * ack-processing since the * data stream in our send-map * will start at snd_una + 1 (one * beyond the SYN). If its just * equal we don't need to do that * and there is no send_map. */ tp->snd_una++; } /* * Received in SYN_SENT[*] state. Transitions: * SYN_SENT --> ESTABLISHED SYN_SENT* --> FIN_WAIT_1 */ tp->t_starttime = ticks; if (tp->t_flags & TF_NEEDFIN) { tcp_state_change(tp, TCPS_FIN_WAIT_1); tp->t_flags &= ~TF_NEEDFIN; thflags &= ~TH_SYN; } else { tcp_state_change(tp, TCPS_ESTABLISHED); TCP_PROBE5(connect__established, NULL, tp, mtod(m, const char *), tp, th); rack_cc_conn_init(tp); } } else { /* * Received initial SYN in SYN-SENT[*] state => simultaneous * open. If segment contains CC option and there is a * cached CC, apply TAO test. If it succeeds, connection is * * half-synchronized. Otherwise, do 3-way handshake: * SYN-SENT -> SYN-RECEIVED SYN-SENT* -> SYN-RECEIVED* If * there was no CC option, clear cached CC value. */ tp->t_flags |= (TF_ACKNOW | TF_NEEDSYN | TF_SONOTCONN); tcp_state_change(tp, TCPS_SYN_RECEIVED); } /* * Advance th->th_seq to correspond to first data byte. If data, * trim to stay within window, dropping FIN if necessary. */ th->th_seq++; if (tlen > tp->rcv_wnd) { todrop = tlen - tp->rcv_wnd; m_adj(m, -todrop); tlen = tp->rcv_wnd; thflags &= ~TH_FIN; KMOD_TCPSTAT_INC(tcps_rcvpackafterwin); KMOD_TCPSTAT_ADD(tcps_rcvbyteafterwin, todrop); } tp->snd_wl1 = th->th_seq - 1; tp->rcv_up = th->th_seq; /* * Client side of transaction: already sent SYN and data. If the * remote host used T/TCP to validate the SYN, our data will be * ACK'd; if so, enter normal data segment processing in the middle * of step 5, ack processing. Otherwise, goto step 6. */ if (thflags & TH_ACK) { /* For syn-sent we need to possibly update the rtt */ if ((to->to_flags & TOF_TS) != 0 && to->to_tsecr) { uint32_t t, mcts; mcts = tcp_ts_getticks(); t = (mcts - to->to_tsecr) * HPTS_USEC_IN_MSEC; if (!tp->t_rttlow || tp->t_rttlow > t) tp->t_rttlow = t; rack_log_rtt_sample_calc(rack, t, (to->to_tsecr * 1000), (mcts * 1000), 4); tcp_rack_xmit_timer(rack, t + 1, 1, t, 0, NULL, 2); tcp_rack_xmit_timer_commit(rack, tp); } if (rack_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val)) return (ret_val); /* We may have changed to FIN_WAIT_1 above */ if (tp->t_state == TCPS_FIN_WAIT_1) { /* * In FIN_WAIT_1 STATE in addition to the processing * for the ESTABLISHED state if our FIN is now * acknowledged then enter FIN_WAIT_2. */ if (ourfinisacked) { /* * If we can't receive any more data, then * closing user can proceed. Starting the * timer is contrary to the specification, * but if we don't get a FIN we'll hang * forever. * * XXXjl: we should release the tp also, and * use a compressed state. */ if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { soisdisconnected(so); tcp_timer_activate(tp, TT_2MSL, (tcp_fast_finwait2_recycle ? tcp_finwait2_timeout : TP_MAXIDLE(tp))); } tcp_state_change(tp, TCPS_FIN_WAIT_2); } } } return (rack_process_data(m, th, so, tp, drop_hdrlen, tlen, tiwin, thflags, nxt_pkt)); } /* * Return value of 1, the TCB is unlocked and most * likely gone, return value of 0, the TCP is still * locked. */ static int rack_do_syn_recv(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos) { struct tcp_rack *rack; int32_t ret_val = 0; int32_t ourfinisacked = 0; rack = (struct tcp_rack *)tp->t_fb_ptr; ctf_calc_rwin(so, tp); if ((thflags & TH_RST) || (tp->t_fin_is_rst && (thflags & TH_FIN))) return (__ctf_process_rst(m, th, so, tp, &rack->r_ctl.challenge_ack_ts, &rack->r_ctl.challenge_ack_cnt)); if ((thflags & TH_ACK) && (SEQ_LEQ(th->th_ack, tp->snd_una) || SEQ_GT(th->th_ack, tp->snd_max))) { tcp_log_end_status(tp, TCP_EI_STATUS_RST_IN_FRONT); ctf_do_dropwithreset(m, tp, th, BANDLIM_RST_OPENPORT, tlen); return (1); } if (IS_FASTOPEN(tp->t_flags)) { /* * When a TFO connection is in SYN_RECEIVED, the * only valid packets are the initial SYN, a * retransmit/copy of the initial SYN (possibly with * a subset of the original data), a valid ACK, a * FIN, or a RST. */ if ((thflags & (TH_SYN | TH_ACK)) == (TH_SYN | TH_ACK)) { tcp_log_end_status(tp, TCP_EI_STATUS_RST_IN_FRONT); ctf_do_dropwithreset(m, tp, th, BANDLIM_RST_OPENPORT, tlen); return (1); } else if (thflags & TH_SYN) { /* non-initial SYN is ignored */ if ((rack->r_ctl.rc_hpts_flags & PACE_TMR_RXT) || (rack->r_ctl.rc_hpts_flags & PACE_TMR_TLP) || (rack->r_ctl.rc_hpts_flags & PACE_TMR_RACK)) { ctf_do_drop(m, NULL); return (0); } } else if (!(thflags & (TH_ACK | TH_FIN | TH_RST))) { ctf_do_drop(m, NULL); return (0); } } /* * RFC 1323 PAWS: If we have a timestamp reply on this segment and * it's less than ts_recent, drop it. */ if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent && TSTMP_LT(to->to_tsval, tp->ts_recent)) { if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val)) return (ret_val); } /* * In the SYN-RECEIVED state, validate that the packet belongs to * this connection before trimming the data to fit the receive * window. Check the sequence number versus IRS since we know the * sequence numbers haven't wrapped. This is a partial fix for the * "LAND" DoS attack. */ if (SEQ_LT(th->th_seq, tp->irs)) { tcp_log_end_status(tp, TCP_EI_STATUS_RST_IN_FRONT); ctf_do_dropwithreset(m, tp, th, BANDLIM_RST_OPENPORT, tlen); return (1); } if (_ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val, &rack->r_ctl.challenge_ack_ts, &rack->r_ctl.challenge_ack_cnt)) { return (ret_val); } /* * If last ACK falls within this segment's sequence numbers, record * its timestamp. NOTE: 1) That the test incorporates suggestions * from the latest proposal of the tcplw@cray.com list (Braden * 1993/04/26). 2) That updating only on newer timestamps interferes * with our earlier PAWS tests, so this check should be solely * predicated on the sequence space of this segment. 3) That we * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ + * SEG.Len, This modified check allows us to overcome RFC1323's * limitations as described in Stevens TCP/IP Illustrated Vol. 2 * p.869. In such cases, we can still calculate the RTT correctly * when RCV.NXT == Last.ACK.Sent. */ if ((to->to_flags & TOF_TS) != 0 && SEQ_LEQ(th->th_seq, tp->last_ack_sent) && SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen + ((thflags & (TH_SYN | TH_FIN)) != 0))) { tp->ts_recent_age = tcp_ts_getticks(); tp->ts_recent = to->to_tsval; } tp->snd_wnd = tiwin; rack_validate_fo_sendwin_up(tp, rack); /* * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag * is on (half-synchronized state), then queue data for later * processing; else drop segment and return. */ if ((thflags & TH_ACK) == 0) { if (IS_FASTOPEN(tp->t_flags)) { rack_cc_conn_init(tp); } return (rack_process_data(m, th, so, tp, drop_hdrlen, tlen, tiwin, thflags, nxt_pkt)); } KMOD_TCPSTAT_INC(tcps_connects); if (tp->t_flags & TF_SONOTCONN) { tp->t_flags &= ~TF_SONOTCONN; soisconnected(so); } /* Do window scaling? */ if ((tp->t_flags & (TF_RCVD_SCALE | TF_REQ_SCALE)) == (TF_RCVD_SCALE | TF_REQ_SCALE)) { tp->rcv_scale = tp->request_r_scale; } /* * Make transitions: SYN-RECEIVED -> ESTABLISHED SYN-RECEIVED* -> * FIN-WAIT-1 */ tp->t_starttime = ticks; if (IS_FASTOPEN(tp->t_flags) && tp->t_tfo_pending) { tcp_fastopen_decrement_counter(tp->t_tfo_pending); tp->t_tfo_pending = NULL; } if (tp->t_flags & TF_NEEDFIN) { tcp_state_change(tp, TCPS_FIN_WAIT_1); tp->t_flags &= ~TF_NEEDFIN; } else { tcp_state_change(tp, TCPS_ESTABLISHED); TCP_PROBE5(accept__established, NULL, tp, mtod(m, const char *), tp, th); /* * TFO connections call cc_conn_init() during SYN * processing. Calling it again here for such connections * is not harmless as it would undo the snd_cwnd reduction * that occurs when a TFO SYN|ACK is retransmitted. */ if (!IS_FASTOPEN(tp->t_flags)) rack_cc_conn_init(tp); } /* * Account for the ACK of our SYN prior to * regular ACK processing below, except for * simultaneous SYN, which is handled later. */ if (SEQ_GT(th->th_ack, tp->snd_una) && !(tp->t_flags & TF_NEEDSYN)) tp->snd_una++; /* * If segment contains data or ACK, will call tcp_reass() later; if * not, do so now to pass queued data to user. */ if (tlen == 0 && (thflags & TH_FIN) == 0) { (void) tcp_reass(tp, (struct tcphdr *)0, NULL, 0, (struct mbuf *)0); if (tp->t_flags & TF_WAKESOR) { tp->t_flags &= ~TF_WAKESOR; /* NB: sorwakeup_locked() does an implicit unlock. */ sorwakeup_locked(so); } } tp->snd_wl1 = th->th_seq - 1; /* For syn-recv we need to possibly update the rtt */ if ((to->to_flags & TOF_TS) != 0 && to->to_tsecr) { uint32_t t, mcts; mcts = tcp_ts_getticks(); t = (mcts - to->to_tsecr) * HPTS_USEC_IN_MSEC; if (!tp->t_rttlow || tp->t_rttlow > t) tp->t_rttlow = t; rack_log_rtt_sample_calc(rack, t, (to->to_tsecr * 1000), (mcts * 1000), 5); tcp_rack_xmit_timer(rack, t + 1, 1, t, 0, NULL, 2); tcp_rack_xmit_timer_commit(rack, tp); } if (rack_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val)) { return (ret_val); } if (tp->t_state == TCPS_FIN_WAIT_1) { /* We could have went to FIN_WAIT_1 (or EST) above */ /* * In FIN_WAIT_1 STATE in addition to the processing for the * ESTABLISHED state if our FIN is now acknowledged then * enter FIN_WAIT_2. */ if (ourfinisacked) { /* * If we can't receive any more data, then closing * user can proceed. Starting the timer is contrary * to the specification, but if we don't get a FIN * we'll hang forever. * * XXXjl: we should release the tp also, and use a * compressed state. */ if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { soisdisconnected(so); tcp_timer_activate(tp, TT_2MSL, (tcp_fast_finwait2_recycle ? tcp_finwait2_timeout : TP_MAXIDLE(tp))); } tcp_state_change(tp, TCPS_FIN_WAIT_2); } } return (rack_process_data(m, th, so, tp, drop_hdrlen, tlen, tiwin, thflags, nxt_pkt)); } /* * Return value of 1, the TCB is unlocked and most * likely gone, return value of 0, the TCP is still * locked. */ static int rack_do_established(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos) { int32_t ret_val = 0; struct tcp_rack *rack; /* * Header prediction: check for the two common cases of a * uni-directional data xfer. If the packet has no control flags, * is in-sequence, the window didn't change and we're not * retransmitting, it's a candidate. If the length is zero and the * ack moved forward, we're the sender side of the xfer. Just free * the data acked & wake any higher level process that was blocked * waiting for space. If the length is non-zero and the ack didn't * move, we're the receiver side. If we're getting packets in-order * (the reassembly queue is empty), add the data toc The socket * buffer and note that we need a delayed ack. Make sure that the * hidden state-flags are also off. Since we check for * TCPS_ESTABLISHED first, it can only be TH_NEEDSYN. */ rack = (struct tcp_rack *)tp->t_fb_ptr; if (__predict_true(((to->to_flags & TOF_SACK) == 0)) && __predict_true((thflags & (TH_SYN | TH_FIN | TH_RST | TH_ACK)) == TH_ACK) && __predict_true(SEGQ_EMPTY(tp)) && __predict_true(th->th_seq == tp->rcv_nxt)) { if (tlen == 0) { if (rack_fastack(m, th, so, tp, to, drop_hdrlen, tlen, tiwin, nxt_pkt, rack->r_ctl.rc_rcvtime)) { return (0); } } else { if (rack_do_fastnewdata(m, th, so, tp, to, drop_hdrlen, tlen, tiwin, nxt_pkt, iptos)) { return (0); } } } ctf_calc_rwin(so, tp); if ((thflags & TH_RST) || (tp->t_fin_is_rst && (thflags & TH_FIN))) return (__ctf_process_rst(m, th, so, tp, &rack->r_ctl.challenge_ack_ts, &rack->r_ctl.challenge_ack_cnt)); /* * RFC5961 Section 4.2 Send challenge ACK for any SYN in * synchronized state. */ if (thflags & TH_SYN) { ctf_challenge_ack(m, th, tp, iptos, &ret_val); return (ret_val); } /* * RFC 1323 PAWS: If we have a timestamp reply on this segment and * it's less than ts_recent, drop it. */ if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent && TSTMP_LT(to->to_tsval, tp->ts_recent)) { if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val)) return (ret_val); } if (_ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val, &rack->r_ctl.challenge_ack_ts, &rack->r_ctl.challenge_ack_cnt)) { return (ret_val); } /* * If last ACK falls within this segment's sequence numbers, record * its timestamp. NOTE: 1) That the test incorporates suggestions * from the latest proposal of the tcplw@cray.com list (Braden * 1993/04/26). 2) That updating only on newer timestamps interferes * with our earlier PAWS tests, so this check should be solely * predicated on the sequence space of this segment. 3) That we * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ + * SEG.Len, This modified check allows us to overcome RFC1323's * limitations as described in Stevens TCP/IP Illustrated Vol. 2 * p.869. In such cases, we can still calculate the RTT correctly * when RCV.NXT == Last.ACK.Sent. */ if ((to->to_flags & TOF_TS) != 0 && SEQ_LEQ(th->th_seq, tp->last_ack_sent) && SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen + ((thflags & (TH_SYN | TH_FIN)) != 0))) { tp->ts_recent_age = tcp_ts_getticks(); tp->ts_recent = to->to_tsval; } /* * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag * is on (half-synchronized state), then queue data for later * processing; else drop segment and return. */ if ((thflags & TH_ACK) == 0) { if (tp->t_flags & TF_NEEDSYN) { return (rack_process_data(m, th, so, tp, drop_hdrlen, tlen, tiwin, thflags, nxt_pkt)); } else if (tp->t_flags & TF_ACKNOW) { ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val); ((struct tcp_rack *)tp->t_fb_ptr)->r_wanted_output = 1; return (ret_val); } else { ctf_do_drop(m, NULL); return (0); } } /* * Ack processing. */ if (rack_process_ack(m, th, so, tp, to, tiwin, tlen, NULL, thflags, &ret_val)) { return (ret_val); } if (sbavail(&so->so_snd)) { if (ctf_progress_timeout_check(tp, true)) { rack_log_progress_event(rack, tp, tick, PROGRESS_DROP, __LINE__); ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen); return (1); } } /* State changes only happen in rack_process_data() */ return (rack_process_data(m, th, so, tp, drop_hdrlen, tlen, tiwin, thflags, nxt_pkt)); } /* * Return value of 1, the TCB is unlocked and most * likely gone, return value of 0, the TCP is still * locked. */ static int rack_do_close_wait(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos) { int32_t ret_val = 0; struct tcp_rack *rack; rack = (struct tcp_rack *)tp->t_fb_ptr; ctf_calc_rwin(so, tp); if ((thflags & TH_RST) || (tp->t_fin_is_rst && (thflags & TH_FIN))) return (__ctf_process_rst(m, th, so, tp, &rack->r_ctl.challenge_ack_ts, &rack->r_ctl.challenge_ack_cnt)); /* * RFC5961 Section 4.2 Send challenge ACK for any SYN in * synchronized state. */ if (thflags & TH_SYN) { ctf_challenge_ack(m, th, tp, iptos, &ret_val); return (ret_val); } /* * RFC 1323 PAWS: If we have a timestamp reply on this segment and * it's less than ts_recent, drop it. */ if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent && TSTMP_LT(to->to_tsval, tp->ts_recent)) { if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val)) return (ret_val); } if (_ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val, &rack->r_ctl.challenge_ack_ts, &rack->r_ctl.challenge_ack_cnt)) { return (ret_val); } /* * If last ACK falls within this segment's sequence numbers, record * its timestamp. NOTE: 1) That the test incorporates suggestions * from the latest proposal of the tcplw@cray.com list (Braden * 1993/04/26). 2) That updating only on newer timestamps interferes * with our earlier PAWS tests, so this check should be solely * predicated on the sequence space of this segment. 3) That we * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ + * SEG.Len, This modified check allows us to overcome RFC1323's * limitations as described in Stevens TCP/IP Illustrated Vol. 2 * p.869. In such cases, we can still calculate the RTT correctly * when RCV.NXT == Last.ACK.Sent. */ if ((to->to_flags & TOF_TS) != 0 && SEQ_LEQ(th->th_seq, tp->last_ack_sent) && SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen + ((thflags & (TH_SYN | TH_FIN)) != 0))) { tp->ts_recent_age = tcp_ts_getticks(); tp->ts_recent = to->to_tsval; } /* * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag * is on (half-synchronized state), then queue data for later * processing; else drop segment and return. */ if ((thflags & TH_ACK) == 0) { if (tp->t_flags & TF_NEEDSYN) { return (rack_process_data(m, th, so, tp, drop_hdrlen, tlen, tiwin, thflags, nxt_pkt)); } else if (tp->t_flags & TF_ACKNOW) { ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val); ((struct tcp_rack *)tp->t_fb_ptr)->r_wanted_output = 1; return (ret_val); } else { ctf_do_drop(m, NULL); return (0); } } /* * Ack processing. */ if (rack_process_ack(m, th, so, tp, to, tiwin, tlen, NULL, thflags, &ret_val)) { return (ret_val); } if (sbavail(&so->so_snd)) { if (ctf_progress_timeout_check(tp, true)) { rack_log_progress_event((struct tcp_rack *)tp->t_fb_ptr, tp, tick, PROGRESS_DROP, __LINE__); ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen); return (1); } } return (rack_process_data(m, th, so, tp, drop_hdrlen, tlen, tiwin, thflags, nxt_pkt)); } static int rack_check_data_after_close(struct mbuf *m, struct tcpcb *tp, int32_t *tlen, struct tcphdr *th, struct socket *so) { struct tcp_rack *rack; rack = (struct tcp_rack *)tp->t_fb_ptr; if (rack->rc_allow_data_af_clo == 0) { close_now: tcp_log_end_status(tp, TCP_EI_STATUS_DATA_A_CLOSE); /* tcp_close will kill the inp pre-log the Reset */ tcp_log_end_status(tp, TCP_EI_STATUS_SERVER_RST); tp = tcp_close(tp); KMOD_TCPSTAT_INC(tcps_rcvafterclose); ctf_do_dropwithreset(m, tp, th, BANDLIM_UNLIMITED, (*tlen)); return (1); } if (sbavail(&so->so_snd) == 0) goto close_now; /* Ok we allow data that is ignored and a followup reset */ tcp_log_end_status(tp, TCP_EI_STATUS_DATA_A_CLOSE); tp->rcv_nxt = th->th_seq + *tlen; tp->t_flags2 |= TF2_DROP_AF_DATA; rack->r_wanted_output = 1; *tlen = 0; return (0); } /* * Return value of 1, the TCB is unlocked and most * likely gone, return value of 0, the TCP is still * locked. */ static int rack_do_fin_wait_1(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos) { int32_t ret_val = 0; int32_t ourfinisacked = 0; struct tcp_rack *rack; rack = (struct tcp_rack *)tp->t_fb_ptr; ctf_calc_rwin(so, tp); if ((thflags & TH_RST) || (tp->t_fin_is_rst && (thflags & TH_FIN))) return (__ctf_process_rst(m, th, so, tp, &rack->r_ctl.challenge_ack_ts, &rack->r_ctl.challenge_ack_cnt)); /* * RFC5961 Section 4.2 Send challenge ACK for any SYN in * synchronized state. */ if (thflags & TH_SYN) { ctf_challenge_ack(m, th, tp, iptos, &ret_val); return (ret_val); } /* * RFC 1323 PAWS: If we have a timestamp reply on this segment and * it's less than ts_recent, drop it. */ if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent && TSTMP_LT(to->to_tsval, tp->ts_recent)) { if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val)) return (ret_val); } if (_ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val, &rack->r_ctl.challenge_ack_ts, &rack->r_ctl.challenge_ack_cnt)) { return (ret_val); } /* * If new data are received on a connection after the user processes * are gone, then RST the other end. */ if ((tp->t_flags & TF_CLOSED) && tlen && rack_check_data_after_close(m, tp, &tlen, th, so)) return (1); /* * If last ACK falls within this segment's sequence numbers, record * its timestamp. NOTE: 1) That the test incorporates suggestions * from the latest proposal of the tcplw@cray.com list (Braden * 1993/04/26). 2) That updating only on newer timestamps interferes * with our earlier PAWS tests, so this check should be solely * predicated on the sequence space of this segment. 3) That we * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ + * SEG.Len, This modified check allows us to overcome RFC1323's * limitations as described in Stevens TCP/IP Illustrated Vol. 2 * p.869. In such cases, we can still calculate the RTT correctly * when RCV.NXT == Last.ACK.Sent. */ if ((to->to_flags & TOF_TS) != 0 && SEQ_LEQ(th->th_seq, tp->last_ack_sent) && SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen + ((thflags & (TH_SYN | TH_FIN)) != 0))) { tp->ts_recent_age = tcp_ts_getticks(); tp->ts_recent = to->to_tsval; } /* * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag * is on (half-synchronized state), then queue data for later * processing; else drop segment and return. */ if ((thflags & TH_ACK) == 0) { if (tp->t_flags & TF_NEEDSYN) { return (rack_process_data(m, th, so, tp, drop_hdrlen, tlen, tiwin, thflags, nxt_pkt)); } else if (tp->t_flags & TF_ACKNOW) { ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val); ((struct tcp_rack *)tp->t_fb_ptr)->r_wanted_output = 1; return (ret_val); } else { ctf_do_drop(m, NULL); return (0); } } /* * Ack processing. */ if (rack_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val)) { return (ret_val); } if (ourfinisacked) { /* * If we can't receive any more data, then closing user can * proceed. Starting the timer is contrary to the * specification, but if we don't get a FIN we'll hang * forever. * * XXXjl: we should release the tp also, and use a * compressed state. */ if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { soisdisconnected(so); tcp_timer_activate(tp, TT_2MSL, (tcp_fast_finwait2_recycle ? tcp_finwait2_timeout : TP_MAXIDLE(tp))); } tcp_state_change(tp, TCPS_FIN_WAIT_2); } if (sbavail(&so->so_snd)) { if (ctf_progress_timeout_check(tp, true)) { rack_log_progress_event((struct tcp_rack *)tp->t_fb_ptr, tp, tick, PROGRESS_DROP, __LINE__); ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen); return (1); } } return (rack_process_data(m, th, so, tp, drop_hdrlen, tlen, tiwin, thflags, nxt_pkt)); } /* * Return value of 1, the TCB is unlocked and most * likely gone, return value of 0, the TCP is still * locked. */ static int rack_do_closing(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos) { int32_t ret_val = 0; int32_t ourfinisacked = 0; struct tcp_rack *rack; rack = (struct tcp_rack *)tp->t_fb_ptr; ctf_calc_rwin(so, tp); if ((thflags & TH_RST) || (tp->t_fin_is_rst && (thflags & TH_FIN))) return (__ctf_process_rst(m, th, so, tp, &rack->r_ctl.challenge_ack_ts, &rack->r_ctl.challenge_ack_cnt)); /* * RFC5961 Section 4.2 Send challenge ACK for any SYN in * synchronized state. */ if (thflags & TH_SYN) { ctf_challenge_ack(m, th, tp, iptos, &ret_val); return (ret_val); } /* * RFC 1323 PAWS: If we have a timestamp reply on this segment and * it's less than ts_recent, drop it. */ if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent && TSTMP_LT(to->to_tsval, tp->ts_recent)) { if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val)) return (ret_val); } if (_ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val, &rack->r_ctl.challenge_ack_ts, &rack->r_ctl.challenge_ack_cnt)) { return (ret_val); } /* * If new data are received on a connection after the user processes * are gone, then RST the other end. */ if ((tp->t_flags & TF_CLOSED) && tlen && rack_check_data_after_close(m, tp, &tlen, th, so)) return (1); /* * If last ACK falls within this segment's sequence numbers, record * its timestamp. NOTE: 1) That the test incorporates suggestions * from the latest proposal of the tcplw@cray.com list (Braden * 1993/04/26). 2) That updating only on newer timestamps interferes * with our earlier PAWS tests, so this check should be solely * predicated on the sequence space of this segment. 3) That we * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ + * SEG.Len, This modified check allows us to overcome RFC1323's * limitations as described in Stevens TCP/IP Illustrated Vol. 2 * p.869. In such cases, we can still calculate the RTT correctly * when RCV.NXT == Last.ACK.Sent. */ if ((to->to_flags & TOF_TS) != 0 && SEQ_LEQ(th->th_seq, tp->last_ack_sent) && SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen + ((thflags & (TH_SYN | TH_FIN)) != 0))) { tp->ts_recent_age = tcp_ts_getticks(); tp->ts_recent = to->to_tsval; } /* * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag * is on (half-synchronized state), then queue data for later * processing; else drop segment and return. */ if ((thflags & TH_ACK) == 0) { if (tp->t_flags & TF_NEEDSYN) { return (rack_process_data(m, th, so, tp, drop_hdrlen, tlen, tiwin, thflags, nxt_pkt)); } else if (tp->t_flags & TF_ACKNOW) { ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val); ((struct tcp_rack *)tp->t_fb_ptr)->r_wanted_output = 1; return (ret_val); } else { ctf_do_drop(m, NULL); return (0); } } /* * Ack processing. */ if (rack_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val)) { return (ret_val); } if (ourfinisacked) { tcp_twstart(tp); m_freem(m); return (1); } if (sbavail(&so->so_snd)) { if (ctf_progress_timeout_check(tp, true)) { rack_log_progress_event((struct tcp_rack *)tp->t_fb_ptr, tp, tick, PROGRESS_DROP, __LINE__); ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen); return (1); } } return (rack_process_data(m, th, so, tp, drop_hdrlen, tlen, tiwin, thflags, nxt_pkt)); } /* * Return value of 1, the TCB is unlocked and most * likely gone, return value of 0, the TCP is still * locked. */ static int rack_do_lastack(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos) { int32_t ret_val = 0; int32_t ourfinisacked = 0; struct tcp_rack *rack; rack = (struct tcp_rack *)tp->t_fb_ptr; ctf_calc_rwin(so, tp); if ((thflags & TH_RST) || (tp->t_fin_is_rst && (thflags & TH_FIN))) return (__ctf_process_rst(m, th, so, tp, &rack->r_ctl.challenge_ack_ts, &rack->r_ctl.challenge_ack_cnt)); /* * RFC5961 Section 4.2 Send challenge ACK for any SYN in * synchronized state. */ if (thflags & TH_SYN) { ctf_challenge_ack(m, th, tp, iptos, &ret_val); return (ret_val); } /* * RFC 1323 PAWS: If we have a timestamp reply on this segment and * it's less than ts_recent, drop it. */ if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent && TSTMP_LT(to->to_tsval, tp->ts_recent)) { if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val)) return (ret_val); } if (_ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val, &rack->r_ctl.challenge_ack_ts, &rack->r_ctl.challenge_ack_cnt)) { return (ret_val); } /* * If new data are received on a connection after the user processes * are gone, then RST the other end. */ if ((tp->t_flags & TF_CLOSED) && tlen && rack_check_data_after_close(m, tp, &tlen, th, so)) return (1); /* * If last ACK falls within this segment's sequence numbers, record * its timestamp. NOTE: 1) That the test incorporates suggestions * from the latest proposal of the tcplw@cray.com list (Braden * 1993/04/26). 2) That updating only on newer timestamps interferes * with our earlier PAWS tests, so this check should be solely * predicated on the sequence space of this segment. 3) That we * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ + * SEG.Len, This modified check allows us to overcome RFC1323's * limitations as described in Stevens TCP/IP Illustrated Vol. 2 * p.869. In such cases, we can still calculate the RTT correctly * when RCV.NXT == Last.ACK.Sent. */ if ((to->to_flags & TOF_TS) != 0 && SEQ_LEQ(th->th_seq, tp->last_ack_sent) && SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen + ((thflags & (TH_SYN | TH_FIN)) != 0))) { tp->ts_recent_age = tcp_ts_getticks(); tp->ts_recent = to->to_tsval; } /* * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag * is on (half-synchronized state), then queue data for later * processing; else drop segment and return. */ if ((thflags & TH_ACK) == 0) { if (tp->t_flags & TF_NEEDSYN) { return (rack_process_data(m, th, so, tp, drop_hdrlen, tlen, tiwin, thflags, nxt_pkt)); } else if (tp->t_flags & TF_ACKNOW) { ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val); ((struct tcp_rack *)tp->t_fb_ptr)->r_wanted_output = 1; return (ret_val); } else { ctf_do_drop(m, NULL); return (0); } } /* * case TCPS_LAST_ACK: Ack processing. */ if (rack_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val)) { return (ret_val); } if (ourfinisacked) { tp = tcp_close(tp); ctf_do_drop(m, tp); return (1); } if (sbavail(&so->so_snd)) { if (ctf_progress_timeout_check(tp, true)) { rack_log_progress_event((struct tcp_rack *)tp->t_fb_ptr, tp, tick, PROGRESS_DROP, __LINE__); ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen); return (1); } } return (rack_process_data(m, th, so, tp, drop_hdrlen, tlen, tiwin, thflags, nxt_pkt)); } /* * Return value of 1, the TCB is unlocked and most * likely gone, return value of 0, the TCP is still * locked. */ static int rack_do_fin_wait_2(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos) { int32_t ret_val = 0; int32_t ourfinisacked = 0; struct tcp_rack *rack; rack = (struct tcp_rack *)tp->t_fb_ptr; ctf_calc_rwin(so, tp); /* Reset receive buffer auto scaling when not in bulk receive mode. */ if ((thflags & TH_RST) || (tp->t_fin_is_rst && (thflags & TH_FIN))) return (__ctf_process_rst(m, th, so, tp, &rack->r_ctl.challenge_ack_ts, &rack->r_ctl.challenge_ack_cnt)); /* * RFC5961 Section 4.2 Send challenge ACK for any SYN in * synchronized state. */ if (thflags & TH_SYN) { ctf_challenge_ack(m, th, tp, iptos, &ret_val); return (ret_val); } /* * RFC 1323 PAWS: If we have a timestamp reply on this segment and * it's less than ts_recent, drop it. */ if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent && TSTMP_LT(to->to_tsval, tp->ts_recent)) { if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val)) return (ret_val); } if (_ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val, &rack->r_ctl.challenge_ack_ts, &rack->r_ctl.challenge_ack_cnt)) { return (ret_val); } /* * If new data are received on a connection after the user processes * are gone, then RST the other end. */ if ((tp->t_flags & TF_CLOSED) && tlen && rack_check_data_after_close(m, tp, &tlen, th, so)) return (1); /* * If last ACK falls within this segment's sequence numbers, record * its timestamp. NOTE: 1) That the test incorporates suggestions * from the latest proposal of the tcplw@cray.com list (Braden * 1993/04/26). 2) That updating only on newer timestamps interferes * with our earlier PAWS tests, so this check should be solely * predicated on the sequence space of this segment. 3) That we * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ + * SEG.Len, This modified check allows us to overcome RFC1323's * limitations as described in Stevens TCP/IP Illustrated Vol. 2 * p.869. In such cases, we can still calculate the RTT correctly * when RCV.NXT == Last.ACK.Sent. */ if ((to->to_flags & TOF_TS) != 0 && SEQ_LEQ(th->th_seq, tp->last_ack_sent) && SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen + ((thflags & (TH_SYN | TH_FIN)) != 0))) { tp->ts_recent_age = tcp_ts_getticks(); tp->ts_recent = to->to_tsval; } /* * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag * is on (half-synchronized state), then queue data for later * processing; else drop segment and return. */ if ((thflags & TH_ACK) == 0) { if (tp->t_flags & TF_NEEDSYN) { return (rack_process_data(m, th, so, tp, drop_hdrlen, tlen, tiwin, thflags, nxt_pkt)); } else if (tp->t_flags & TF_ACKNOW) { ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val); ((struct tcp_rack *)tp->t_fb_ptr)->r_wanted_output = 1; return (ret_val); } else { ctf_do_drop(m, NULL); return (0); } } /* * Ack processing. */ if (rack_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val)) { return (ret_val); } if (sbavail(&so->so_snd)) { if (ctf_progress_timeout_check(tp, true)) { rack_log_progress_event((struct tcp_rack *)tp->t_fb_ptr, tp, tick, PROGRESS_DROP, __LINE__); ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen); return (1); } } return (rack_process_data(m, th, so, tp, drop_hdrlen, tlen, tiwin, thflags, nxt_pkt)); } static void inline rack_clear_rate_sample(struct tcp_rack *rack) { rack->r_ctl.rack_rs.rs_flags = RACK_RTT_EMPTY; rack->r_ctl.rack_rs.rs_rtt_cnt = 0; rack->r_ctl.rack_rs.rs_rtt_tot = 0; } static void rack_set_pace_segments(struct tcpcb *tp, struct tcp_rack *rack, uint32_t line, uint64_t *fill_override) { uint64_t bw_est, rate_wanted; int chged = 0; uint32_t user_max, orig_min, orig_max; #ifdef TCP_REQUEST_TRK if (rack->rc_hybrid_mode && (rack->r_ctl.rc_pace_max_segs != 0) && (rack_hybrid_allow_set_maxseg == 1) && (rack->r_ctl.rc_last_sft != NULL)) { rack->r_ctl.rc_last_sft->hybrid_flags &= ~TCP_HYBRID_PACING_SETMSS; return; } #endif orig_min = rack->r_ctl.rc_pace_min_segs; orig_max = rack->r_ctl.rc_pace_max_segs; user_max = ctf_fixed_maxseg(tp) * rack->rc_user_set_max_segs; if (ctf_fixed_maxseg(tp) != rack->r_ctl.rc_pace_min_segs) chged = 1; rack->r_ctl.rc_pace_min_segs = ctf_fixed_maxseg(tp); if (rack->use_fixed_rate || rack->rc_force_max_seg) { if (user_max != rack->r_ctl.rc_pace_max_segs) chged = 1; } if (rack->rc_force_max_seg) { rack->r_ctl.rc_pace_max_segs = user_max; } else if (rack->use_fixed_rate) { bw_est = rack_get_bw(rack); if ((rack->r_ctl.crte == NULL) || (bw_est != rack->r_ctl.crte->rate)) { rack->r_ctl.rc_pace_max_segs = user_max; } else { /* We are pacing right at the hardware rate */ uint32_t segsiz, pace_one; if (rack_pace_one_seg || (rack->r_ctl.rc_user_set_min_segs == 1)) pace_one = 1; else pace_one = 0; segsiz = min(ctf_fixed_maxseg(tp), rack->r_ctl.rc_pace_min_segs); rack->r_ctl.rc_pace_max_segs = tcp_get_pacing_burst_size_w_divisor( tp, bw_est, segsiz, pace_one, rack->r_ctl.crte, NULL, rack->r_ctl.pace_len_divisor); } } else if (rack->rc_always_pace) { if (rack->r_ctl.gp_bw || rack->r_ctl.init_rate) { /* We have a rate of some sort set */ uint32_t orig; bw_est = rack_get_bw(rack); orig = rack->r_ctl.rc_pace_max_segs; if (fill_override) rate_wanted = *fill_override; else rate_wanted = rack_get_gp_est(rack); if (rate_wanted) { /* We have something */ rack->r_ctl.rc_pace_max_segs = rack_get_pacing_len(rack, rate_wanted, ctf_fixed_maxseg(rack->rc_tp)); } else rack->r_ctl.rc_pace_max_segs = rack->r_ctl.rc_pace_min_segs; if (orig != rack->r_ctl.rc_pace_max_segs) chged = 1; } else if ((rack->r_ctl.gp_bw == 0) && (rack->r_ctl.rc_pace_max_segs == 0)) { /* * If we have nothing limit us to bursting * out IW sized pieces. */ chged = 1; rack->r_ctl.rc_pace_max_segs = rc_init_window(rack); } } if (rack->r_ctl.rc_pace_max_segs > PACE_MAX_IP_BYTES) { chged = 1; rack->r_ctl.rc_pace_max_segs = PACE_MAX_IP_BYTES; } if (chged) rack_log_type_pacing_sizes(tp, rack, orig_min, orig_max, line, 2); } static void rack_init_fsb_block(struct tcpcb *tp, struct tcp_rack *rack, int32_t flags) { #ifdef INET6 struct ip6_hdr *ip6 = NULL; #endif #ifdef INET struct ip *ip = NULL; #endif struct udphdr *udp = NULL; /* Ok lets fill in the fast block, it can only be used with no IP options! */ #ifdef INET6 if (rack->r_is_v6) { rack->r_ctl.fsb.tcp_ip_hdr_len = sizeof(struct ip6_hdr) + sizeof(struct tcphdr); ip6 = (struct ip6_hdr *)rack->r_ctl.fsb.tcp_ip_hdr; if (tp->t_port) { rack->r_ctl.fsb.tcp_ip_hdr_len += sizeof(struct udphdr); udp = (struct udphdr *)((caddr_t)ip6 + sizeof(struct ip6_hdr)); udp->uh_sport = htons(V_tcp_udp_tunneling_port); udp->uh_dport = tp->t_port; rack->r_ctl.fsb.udp = udp; rack->r_ctl.fsb.th = (struct tcphdr *)(udp + 1); } else { rack->r_ctl.fsb.th = (struct tcphdr *)(ip6 + 1); rack->r_ctl.fsb.udp = NULL; } tcpip_fillheaders(rack->rc_inp, tp->t_port, ip6, rack->r_ctl.fsb.th); rack->r_ctl.fsb.hoplimit = in6_selecthlim(rack->rc_inp, NULL); } else #endif /* INET6 */ #ifdef INET { rack->r_ctl.fsb.tcp_ip_hdr_len = sizeof(struct tcpiphdr); ip = (struct ip *)rack->r_ctl.fsb.tcp_ip_hdr; if (tp->t_port) { rack->r_ctl.fsb.tcp_ip_hdr_len += sizeof(struct udphdr); udp = (struct udphdr *)((caddr_t)ip + sizeof(struct ip)); udp->uh_sport = htons(V_tcp_udp_tunneling_port); udp->uh_dport = tp->t_port; rack->r_ctl.fsb.udp = udp; rack->r_ctl.fsb.th = (struct tcphdr *)(udp + 1); } else { rack->r_ctl.fsb.udp = NULL; rack->r_ctl.fsb.th = (struct tcphdr *)(ip + 1); } tcpip_fillheaders(rack->rc_inp, tp->t_port, ip, rack->r_ctl.fsb.th); rack->r_ctl.fsb.hoplimit = tptoinpcb(tp)->inp_ip_ttl; } #endif rack->r_ctl.fsb.recwin = lmin(lmax(sbspace(&tptosocket(tp)->so_rcv), 0), (long)TCP_MAXWIN << tp->rcv_scale); rack->r_fsb_inited = 1; } static int rack_init_fsb(struct tcpcb *tp, struct tcp_rack *rack) { /* * Allocate the larger of spaces V6 if available else just * V4 and include udphdr (overbook) */ #ifdef INET6 rack->r_ctl.fsb.tcp_ip_hdr_len = sizeof(struct ip6_hdr) + sizeof(struct tcphdr) + sizeof(struct udphdr); #else rack->r_ctl.fsb.tcp_ip_hdr_len = sizeof(struct tcpiphdr) + sizeof(struct udphdr); #endif rack->r_ctl.fsb.tcp_ip_hdr = malloc(rack->r_ctl.fsb.tcp_ip_hdr_len, M_TCPFSB, M_NOWAIT|M_ZERO); if (rack->r_ctl.fsb.tcp_ip_hdr == NULL) { return (ENOMEM); } rack->r_fsb_inited = 0; return (0); } static void rack_log_hystart_event(struct tcp_rack *rack, uint32_t high_seq, uint8_t mod) { /* * Types of logs (mod value) * 20 - Initial round setup * 21 - Rack declares a new round. */ struct tcpcb *tp; tp = rack->rc_tp; if (tcp_bblogging_on(tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log, 0, sizeof(log)); log.u_bbr.flex1 = rack->r_ctl.current_round; log.u_bbr.flex2 = rack->r_ctl.roundends; log.u_bbr.flex3 = high_seq; log.u_bbr.flex4 = tp->snd_max; log.u_bbr.flex8 = mod; log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.cur_del_rate = rack->rc_tp->t_sndbytes; log.u_bbr.delRate = rack->rc_tp->t_snd_rxt_bytes; TCP_LOG_EVENTP(tp, NULL, &tptosocket(tp)->so_rcv, &tptosocket(tp)->so_snd, TCP_HYSTART, 0, 0, &log, false, &tv); } } static void rack_deferred_init(struct tcpcb *tp, struct tcp_rack *rack) { rack->rack_deferred_inited = 1; rack->r_ctl.roundends = tp->snd_max; rack->r_ctl.rc_high_rwnd = tp->snd_wnd; rack->r_ctl.cwnd_to_use = tp->snd_cwnd; } static void rack_init_retransmit_value(struct tcp_rack *rack, int ctl) { /* Retransmit bit controls. * * The setting of these values control one of * three settings you can have and dictate * how rack does retransmissions. Note this * is in *any* mode i.e. pacing on or off DGP * fixed rate pacing, or just bursting rack. * * 1 - Use full sized retransmits i.e. limit * the size to whatever the pace_max_segments * size is. * * 2 - Use pacer min granularity as a guide to * the size combined with the current calculated * goodput b/w measurement. So for example if * the goodput is measured at 20Mbps we would * calculate 8125 (pacer minimum 250usec in * that b/w) and then round it up to the next * MSS i.e. for 1448 mss 6 MSS or 8688 bytes. * * 0 - The rack default 1 MSS (anything not 0/1/2 * fall here too if we are setting via rack_init()). * */ if (ctl == 1) { rack->full_size_rxt = 1; rack->shape_rxt_to_pacing_min = 0; } else if (ctl == 2) { rack->full_size_rxt = 0; rack->shape_rxt_to_pacing_min = 1; } else { rack->full_size_rxt = 0; rack->shape_rxt_to_pacing_min = 0; } } static void rack_log_chg_info(struct tcpcb *tp, struct tcp_rack *rack, uint8_t mod, uint32_t flex1, uint32_t flex2, uint32_t flex3) { if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.flex8 = mod; log.u_bbr.flex1 = flex1; log.u_bbr.flex2 = flex2; log.u_bbr.flex3 = flex3; tcp_log_event(tp, NULL, NULL, NULL, TCP_CHG_QUERY, 0, 0, &log, false, NULL, __func__, __LINE__, &tv); } } static int rack_chg_query(struct tcpcb *tp, struct tcp_query_resp *reqr) { struct tcp_rack *rack; struct rack_sendmap *rsm; int i; rack = (struct tcp_rack *)tp->t_fb_ptr; switch (reqr->req) { case TCP_QUERY_SENDMAP: if ((reqr->req_param == tp->snd_max) || (tp->snd_max == tp->snd_una)){ /* Unlikely */ return (0); } rsm = tqhash_find(rack->r_ctl.tqh, reqr->req_param); if (rsm == NULL) { /* Can't find that seq -- unlikely */ return (0); } reqr->sendmap_start = rsm->r_start; reqr->sendmap_end = rsm->r_end; reqr->sendmap_send_cnt = rsm->r_rtr_cnt; reqr->sendmap_fas = rsm->r_fas; if (reqr->sendmap_send_cnt > SNDMAP_NRTX) reqr->sendmap_send_cnt = SNDMAP_NRTX; for(i=0; isendmap_send_cnt; i++) reqr->sendmap_time[i] = rsm->r_tim_lastsent[i]; reqr->sendmap_ack_arrival = rsm->r_ack_arrival; reqr->sendmap_flags = rsm->r_flags & SNDMAP_MASK; reqr->sendmap_r_rtr_bytes = rsm->r_rtr_bytes; reqr->sendmap_dupacks = rsm->r_dupack; rack_log_chg_info(tp, rack, 1, rsm->r_start, rsm->r_end, rsm->r_flags); return(1); break; case TCP_QUERY_TIMERS_UP: if (rack->r_ctl.rc_hpts_flags == 0) { /* no timers up */ return (0); } reqr->timer_hpts_flags = rack->r_ctl.rc_hpts_flags; if (rack->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) { reqr->timer_pacing_to = rack->r_ctl.rc_last_output_to; } if (rack->r_ctl.rc_hpts_flags & PACE_TMR_MASK) { reqr->timer_timer_exp = rack->r_ctl.rc_timer_exp; } rack_log_chg_info(tp, rack, 2, rack->r_ctl.rc_hpts_flags, rack->r_ctl.rc_last_output_to, rack->r_ctl.rc_timer_exp); return (1); break; case TCP_QUERY_RACK_TIMES: /* Reordering items */ reqr->rack_num_dsacks = rack->r_ctl.num_dsack; reqr->rack_reorder_ts = rack->r_ctl.rc_reorder_ts; /* Timerstamps and timers */ reqr->rack_rxt_last_time = rack->r_ctl.rc_tlp_rxt_last_time; reqr->rack_min_rtt = rack->r_ctl.rc_rack_min_rtt; reqr->rack_rtt = rack->rc_rack_rtt; reqr->rack_tmit_time = rack->r_ctl.rc_rack_tmit_time; reqr->rack_srtt_measured = rack->rc_srtt_measure_made; /* PRR data */ reqr->rack_sacked = rack->r_ctl.rc_sacked; reqr->rack_holes_rxt = rack->r_ctl.rc_holes_rxt; reqr->rack_prr_delivered = rack->r_ctl.rc_prr_delivered; reqr->rack_prr_recovery_fs = rack->r_ctl.rc_prr_recovery_fs; reqr->rack_prr_sndcnt = rack->r_ctl.rc_prr_sndcnt; reqr->rack_prr_out = rack->r_ctl.rc_prr_out; /* TLP and persists info */ reqr->rack_tlp_out = rack->rc_tlp_in_progress; reqr->rack_tlp_cnt_out = rack->r_ctl.rc_tlp_cnt_out; if (rack->rc_in_persist) { reqr->rack_time_went_idle = rack->r_ctl.rc_went_idle_time; reqr->rack_in_persist = 1; } else { reqr->rack_time_went_idle = 0; reqr->rack_in_persist = 0; } if (rack->r_wanted_output) reqr->rack_wanted_output = 1; else reqr->rack_wanted_output = 0; return (1); break; default: return (-EINVAL); } } static void rack_switch_failed(struct tcpcb *tp) { /* * This method gets called if a stack switch was * attempted and it failed. We are left * but our hpts timers were stopped and we * need to validate time units and t_flags2. */ struct tcp_rack *rack; struct timeval tv; uint32_t cts; uint32_t toval; struct hpts_diag diag; rack = (struct tcp_rack *)tp->t_fb_ptr; tcp_change_time_units(tp, TCP_TMR_GRANULARITY_USEC); if (rack->r_mbuf_queue || rack->rc_always_pace || rack->r_use_cmp_ack) tp->t_flags2 |= TF2_SUPPORTS_MBUFQ; else tp->t_flags2 &= ~TF2_SUPPORTS_MBUFQ; if (rack->r_use_cmp_ack && TCPS_HAVEESTABLISHED(tp->t_state)) tp->t_flags2 |= TF2_MBUF_ACKCMP; if (tp->t_in_hpts > IHPTS_NONE) { /* Strange */ return; } cts = tcp_get_usecs(&tv); if (rack->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) { if (TSTMP_GT(rack->r_ctl.rc_last_output_to, cts)) { toval = rack->r_ctl.rc_last_output_to - cts; } else { /* one slot please */ toval = HPTS_TICKS_PER_SLOT; } } else if (rack->r_ctl.rc_hpts_flags & PACE_TMR_MASK) { if (TSTMP_GT(rack->r_ctl.rc_timer_exp, cts)) { toval = rack->r_ctl.rc_timer_exp - cts; } else { /* one slot please */ toval = HPTS_TICKS_PER_SLOT; } } else toval = HPTS_TICKS_PER_SLOT; (void)tcp_hpts_insert_diag(tp, HPTS_USEC_TO_SLOTS(toval), __LINE__, &diag); rack_log_hpts_diag(rack, cts, &diag, &tv); } static int rack_init_outstanding(struct tcpcb *tp, struct tcp_rack *rack, uint32_t us_cts, void *ptr) { struct rack_sendmap *rsm, *ersm; int insret __diagused; /* * When initing outstanding, we must be quite careful * to not refer to tp->t_fb_ptr. This has the old rack * pointer in it, not the "new" one (when we are doing * a stack switch). */ if (tp->t_fb->tfb_chg_query == NULL) { /* Create a send map for the current outstanding data */ rsm = rack_alloc(rack); if (rsm == NULL) { uma_zfree(rack_pcb_zone, ptr); return (ENOMEM); } rsm->r_no_rtt_allowed = 1; rsm->r_tim_lastsent[0] = rack_to_usec_ts(&rack->r_ctl.act_rcv_time); rsm->r_rtr_cnt = 1; rsm->r_rtr_bytes = 0; if (tp->t_flags & TF_SENTFIN) rsm->r_flags |= RACK_HAS_FIN; rsm->r_end = tp->snd_max; if (tp->snd_una == tp->iss) { /* The data space is one beyond snd_una */ rsm->r_flags |= RACK_HAS_SYN; rsm->r_start = tp->iss; rsm->r_end = rsm->r_start + (tp->snd_max - tp->snd_una); } else rsm->r_start = tp->snd_una; rsm->r_dupack = 0; if (rack->rc_inp->inp_socket->so_snd.sb_mb != NULL) { rsm->m = sbsndmbuf(&rack->rc_inp->inp_socket->so_snd, 0, &rsm->soff); if (rsm->m) { rsm->orig_m_len = rsm->m->m_len; rsm->orig_t_space = M_TRAILINGROOM(rsm->m); } else { rsm->orig_m_len = 0; rsm->orig_t_space = 0; } } else { /* * This can happen if we have a stand-alone FIN or * SYN. */ rsm->m = NULL; rsm->orig_m_len = 0; rsm->orig_t_space = 0; rsm->soff = 0; } #ifdef INVARIANTS if ((insret = tqhash_insert(rack->r_ctl.tqh, rsm)) != 0) { panic("Insert in rb tree fails ret:%d rack:%p rsm:%p", insret, rack, rsm); } #else (void)tqhash_insert(rack->r_ctl.tqh, rsm); #endif TAILQ_INSERT_TAIL(&rack->r_ctl.rc_tmap, rsm, r_tnext); rsm->r_in_tmap = 1; } else { /* We have a query mechanism, lets use it */ struct tcp_query_resp qr; int i; tcp_seq at; at = tp->snd_una; while (at != tp->snd_max) { memset(&qr, 0, sizeof(qr)); qr.req = TCP_QUERY_SENDMAP; qr.req_param = at; if ((*tp->t_fb->tfb_chg_query)(tp, &qr) == 0) break; /* Move forward */ at = qr.sendmap_end; /* Now lets build the entry for this one */ rsm = rack_alloc(rack); if (rsm == NULL) { uma_zfree(rack_pcb_zone, ptr); return (ENOMEM); } memset(rsm, 0, sizeof(struct rack_sendmap)); /* Now configure the rsm and insert it */ rsm->r_dupack = qr.sendmap_dupacks; rsm->r_start = qr.sendmap_start; rsm->r_end = qr.sendmap_end; if (qr.sendmap_fas) rsm->r_fas = qr.sendmap_end; else rsm->r_fas = rsm->r_start - tp->snd_una; /* * We have carefully aligned the bits * so that all we have to do is copy over * the bits with the mask. */ rsm->r_flags = qr.sendmap_flags & SNDMAP_MASK; rsm->r_rtr_bytes = qr.sendmap_r_rtr_bytes; rsm->r_rtr_cnt = qr.sendmap_send_cnt; rsm->r_ack_arrival = qr.sendmap_ack_arrival; for (i=0 ; ir_rtr_cnt; i++) rsm->r_tim_lastsent[i] = qr.sendmap_time[i]; rsm->m = sbsndmbuf(&rack->rc_inp->inp_socket->so_snd, (rsm->r_start - tp->snd_una), &rsm->soff); if (rsm->m) { rsm->orig_m_len = rsm->m->m_len; rsm->orig_t_space = M_TRAILINGROOM(rsm->m); } else { rsm->orig_m_len = 0; rsm->orig_t_space = 0; } #ifdef INVARIANTS if ((insret = tqhash_insert(rack->r_ctl.tqh, rsm)) != 0) { panic("Insert in rb tree fails ret:%d rack:%p rsm:%p", insret, rack, rsm); } #else (void)tqhash_insert(rack->r_ctl.tqh, rsm); #endif if ((rsm->r_flags & RACK_ACKED) == 0) { TAILQ_FOREACH(ersm, &rack->r_ctl.rc_tmap, r_tnext) { if (ersm->r_tim_lastsent[(ersm->r_rtr_cnt-1)] > rsm->r_tim_lastsent[(rsm->r_rtr_cnt-1)]) { /* * If the existing ersm was sent at * a later time than the new one, then * the new one should appear ahead of this * ersm. */ rsm->r_in_tmap = 1; TAILQ_INSERT_BEFORE(ersm, rsm, r_tnext); break; } } if (rsm->r_in_tmap == 0) { /* * Not found so shove it on the tail. */ TAILQ_INSERT_TAIL(&rack->r_ctl.rc_tmap, rsm, r_tnext); rsm->r_in_tmap = 1; } } else { if ((rack->r_ctl.rc_sacklast == NULL) || (SEQ_GT(rsm->r_end, rack->r_ctl.rc_sacklast->r_end))) { rack->r_ctl.rc_sacklast = rsm; } } rack_log_chg_info(tp, rack, 3, rsm->r_start, rsm->r_end, rsm->r_flags); } } return (0); } static void rack_translate_clamp_value(struct tcp_rack *rack, uint32_t optval) { /* * P = percent bits * F = fill cw bit -- Toggle fillcw if this bit is set. * S = Segment bits * M = set max segment bit * U = Unclamined * C = If set to non-zero override the max number of clamps. * L = Bit to indicate if clamped gets lower. * * CCCC CCCCC UUUU UULF PPPP PPPP PPPP PPPP * * The lowest 3 nibbles is the perentage .1 - 6553.5% * where 10.1 = 101, max 6553.5 * The upper 16 bits holds some options. * The F bit will turn on fill-cw on if you are * not pacing, it will turn it off if dgp is on. * The L bit will change it so when clamped we get * the min(gp, lt-bw) for dgp. */ uint16_t per; rack->r_ctl.saved_rxt_clamp_val = optval; per = optval & 0x0000ffff; rack->r_ctl.rxt_threshold = (uint64_t)(per & 0xffff); if (optval > 0) { uint16_t clamp_opt; rack->excess_rxt_on = 1; clamp_opt = ((optval & 0xffff0000) >> 16); rack->r_ctl.clamp_options = clamp_opt & 0x00ff; if (clamp_opt & 0xff00) { /* A max clamps is also present */ rack->r_ctl.max_clamps = (clamp_opt >> 8); } else { /* No specified clamps means no limit */ rack->r_ctl.max_clamps = 0; } if (rack->r_ctl.clamp_options & 0x0002) { rack->r_clamped_gets_lower = 1; } else { rack->r_clamped_gets_lower = 0; } } else { /* Turn it off back to default */ rack->excess_rxt_on = 0; rack->r_clamped_gets_lower = 0; } } static int32_t rack_init(struct tcpcb *tp, void **ptr) { struct inpcb *inp = tptoinpcb(tp); struct tcp_rack *rack = NULL; uint32_t iwin, snt, us_cts; int err, no_query; /* * First are we the initial or are we a switched stack? * If we are initing via tcp_newtcppcb the ptr passed * will be tp->t_fb_ptr. If its a stack switch that * has a previous stack we can query it will be a local * var that will in the end be set into t_fb_ptr. */ if (ptr == &tp->t_fb_ptr) no_query = 1; else no_query = 0; *ptr = uma_zalloc(rack_pcb_zone, M_NOWAIT); if (*ptr == NULL) { /* * We need to allocate memory but cant. The INP and INP_INFO * locks and they are recursive (happens during setup. So a * scheme to drop the locks fails :( * */ return(ENOMEM); } memset(*ptr, 0, sizeof(struct tcp_rack)); rack = (struct tcp_rack *)*ptr; rack->r_ctl.tqh = malloc(sizeof(struct tailq_hash), M_TCPFSB, M_NOWAIT); if (rack->r_ctl.tqh == NULL) { uma_zfree(rack_pcb_zone, rack); return(ENOMEM); } tqhash_init(rack->r_ctl.tqh); TAILQ_INIT(&rack->r_ctl.rc_free); TAILQ_INIT(&rack->r_ctl.rc_tmap); rack->rc_tp = tp; rack->rc_inp = inp; /* Set the flag */ rack->r_is_v6 = (inp->inp_vflag & INP_IPV6) != 0; /* Probably not needed but lets be sure */ rack_clear_rate_sample(rack); /* * Save off the default values, socket options will poke * at these if pacing is not on or we have not yet * reached where pacing is on (gp_ready/fixed enabled). * When they get set into the CC module (when gp_ready * is enabled or we enable fixed) then we will set these * values into the CC and place in here the old values * so we have a restoral. Then we will set the flag * rc_pacing_cc_set. That way whenever we turn off pacing * or switch off this stack, we will know to go restore * the saved values. * * We specifically put into the beta the ecn value for pacing. */ rack->rc_new_rnd_needed = 1; rack->r_ctl.rc_split_limit = V_tcp_map_split_limit; /* We want abe like behavior as well */ rack->r_ctl.rc_saved_beta.newreno_flags |= CC_NEWRENO_BETA_ECN_ENABLED; rack->r_ctl.rc_reorder_fade = rack_reorder_fade; rack->rc_allow_data_af_clo = rack_ignore_data_after_close; rack->r_ctl.rc_tlp_threshold = rack_tlp_thresh; if (rack_rxt_clamp_thresh) { rack_translate_clamp_value(rack, rack_rxt_clamp_thresh); rack->excess_rxt_on = 1; } if (rack_uses_full_dgp_in_rec) rack->r_ctl.full_dgp_in_rec = 1; if (rack_fill_cw_state) rack->rc_pace_to_cwnd = 1; if (rack_pacing_min_seg) rack->r_ctl.rc_user_set_min_segs = rack_pacing_min_seg; if (use_rack_rr) rack->use_rack_rr = 1; if (rack_dnd_default) { rack->rc_pace_dnd = 1; } if (V_tcp_delack_enabled) tp->t_delayed_ack = 1; else tp->t_delayed_ack = 0; #ifdef TCP_ACCOUNTING if (rack_tcp_accounting) { tp->t_flags2 |= TF2_TCP_ACCOUNTING; } #endif rack->r_ctl.rack_per_upper_bound_ss = (uint8_t)rack_per_upper_bound_ss; rack->r_ctl.rack_per_upper_bound_ca = (uint8_t)rack_per_upper_bound_ca; if (rack_enable_shared_cwnd) rack->rack_enable_scwnd = 1; rack->r_ctl.pace_len_divisor = rack_default_pacing_divisor; rack->rc_user_set_max_segs = rack_hptsi_segments; rack->rc_force_max_seg = 0; TAILQ_INIT(&rack->r_ctl.opt_list); rack->r_ctl.rc_saved_beta.beta = V_newreno_beta_ecn; rack->r_ctl.rc_saved_beta.beta_ecn = V_newreno_beta_ecn; if (rack_hibeta_setting) { rack->rack_hibeta = 1; if ((rack_hibeta_setting >= 50) && (rack_hibeta_setting <= 100)) { rack->r_ctl.rc_saved_beta.beta = rack_hibeta_setting; rack->r_ctl.saved_hibeta = rack_hibeta_setting; } } else { rack->r_ctl.saved_hibeta = 50; } rack->r_ctl.rc_reorder_shift = rack_reorder_thresh; rack->r_ctl.rc_pkt_delay = rack_pkt_delay; rack->r_ctl.rc_tlp_cwnd_reduce = rack_lower_cwnd_at_tlp; rack->r_ctl.rc_lowest_us_rtt = 0xffffffff; rack->r_ctl.rc_highest_us_rtt = 0; rack->r_ctl.bw_rate_cap = rack_bw_rate_cap; rack->r_ctl.timer_slop = TICKS_2_USEC(tcp_rexmit_slop); if (rack_use_cmp_acks) rack->r_use_cmp_ack = 1; if (rack_disable_prr) rack->rack_no_prr = 1; if (rack_gp_no_rec_chg) rack->rc_gp_no_rec_chg = 1; if (rack_pace_every_seg && tcp_can_enable_pacing()) { rack->rc_always_pace = 1; if (rack->rack_hibeta) rack_set_cc_pacing(rack); } else rack->rc_always_pace = 0; if (rack_enable_mqueue_for_nonpaced || rack->r_use_cmp_ack) rack->r_mbuf_queue = 1; else rack->r_mbuf_queue = 0; rack_set_pace_segments(tp, rack, __LINE__, NULL); if (rack_limits_scwnd) rack->r_limit_scw = 1; else rack->r_limit_scw = 0; rack_init_retransmit_value(rack, rack_rxt_controls); rack->rc_labc = V_tcp_abc_l_var; rack->r_ctl.rc_rate_sample_method = rack_rate_sample_method; rack->rack_tlp_threshold_use = rack_tlp_threshold_use; rack->r_ctl.rc_prr_sendalot = rack_send_a_lot_in_prr; rack->r_ctl.rc_min_to = rack_min_to; microuptime(&rack->r_ctl.act_rcv_time); rack->r_ctl.rc_last_time_decay = rack->r_ctl.act_rcv_time; rack->rc_init_win = rack_default_init_window; rack->r_ctl.rack_per_of_gp_ss = rack_per_of_gp_ss; if (rack_hw_up_only) rack->r_up_only = 1; if (rack_do_dyn_mul) { /* When dynamic adjustment is on CA needs to start at 100% */ rack->rc_gp_dyn_mul = 1; if (rack_do_dyn_mul >= 100) rack->r_ctl.rack_per_of_gp_ca = rack_do_dyn_mul; } else rack->r_ctl.rack_per_of_gp_ca = rack_per_of_gp_ca; rack->r_ctl.rack_per_of_gp_rec = rack_per_of_gp_rec; rack->r_ctl.rack_per_of_gp_probertt = rack_per_of_gp_probertt; rack->r_ctl.rc_tlp_rxt_last_time = tcp_tv_to_mssectick(&rack->r_ctl.act_rcv_time); setup_time_filter_small(&rack->r_ctl.rc_gp_min_rtt, FILTER_TYPE_MIN, rack_probertt_filter_life); us_cts = tcp_tv_to_usectick(&rack->r_ctl.act_rcv_time); rack->r_ctl.rc_lower_rtt_us_cts = us_cts; rack->r_ctl.rc_time_of_last_probertt = us_cts; rack->r_ctl.challenge_ack_ts = tcp_ts_getticks(); rack->r_ctl.rc_time_probertt_starts = 0; if (rack_dsack_std_based & 0x1) { /* Basically this means all rack timers are at least (srtt + 1/4 srtt) */ rack->rc_rack_tmr_std_based = 1; } if (rack_dsack_std_based & 0x2) { /* Basically this means rack timers are extended based on dsack by up to (2 * srtt) */ rack->rc_rack_use_dsack = 1; } /* We require at least one measurement, even if the sysctl is 0 */ if (rack_req_measurements) rack->r_ctl.req_measurements = rack_req_measurements; else rack->r_ctl.req_measurements = 1; if (rack_enable_hw_pacing) rack->rack_hdw_pace_ena = 1; if (rack_hw_rate_caps) rack->r_rack_hw_rate_caps = 1; #ifdef TCP_SAD_DETECTION rack->do_detection = 1; #else rack->do_detection = 0; #endif if (rack_non_rxt_use_cr) rack->rack_rec_nonrxt_use_cr = 1; /* Lets setup the fsb block */ err = rack_init_fsb(tp, rack); if (err) { uma_zfree(rack_pcb_zone, *ptr); *ptr = NULL; return (err); } if (rack_do_hystart) { tp->t_ccv.flags |= CCF_HYSTART_ALLOWED; if (rack_do_hystart > 1) tp->t_ccv.flags |= CCF_HYSTART_CAN_SH_CWND; if (rack_do_hystart > 2) tp->t_ccv.flags |= CCF_HYSTART_CONS_SSTH; } /* Log what we will do with queries */ rack_log_chg_info(tp, rack, 7, no_query, 0, 0); if (rack_def_profile) rack_set_profile(rack, rack_def_profile); /* Cancel the GP measurement in progress */ tp->t_flags &= ~TF_GPUTINPROG; if ((tp->t_state != TCPS_CLOSED) && (tp->t_state != TCPS_TIME_WAIT)) { /* * We are already open, we may * need to adjust a few things. */ if (SEQ_GT(tp->snd_max, tp->iss)) snt = tp->snd_max - tp->iss; else snt = 0; iwin = rc_init_window(rack); if ((snt < iwin) && (no_query == 1)) { /* We are not past the initial window * on the first init (i.e. a stack switch * has not yet occured) so we need to make * sure cwnd and ssthresh is correct. */ if (tp->snd_cwnd < iwin) tp->snd_cwnd = iwin; /* * If we are within the initial window * we want ssthresh to be unlimited. Setting * it to the rwnd (which the default stack does * and older racks) is not really a good idea * since we want to be in SS and grow both the * cwnd and the rwnd (via dynamic rwnd growth). If * we set it to the rwnd then as the peer grows its * rwnd we will be stuck in CA and never hit SS. * * Its far better to raise it up high (this takes the * risk that there as been a loss already, probably * we should have an indicator in all stacks of loss * but we don't), but considering the normal use this * is a risk worth taking. The consequences of not * hitting SS are far worse than going one more time * into it early on (before we have sent even a IW). * It is highly unlikely that we will have had a loss * before getting the IW out. */ tp->snd_ssthresh = 0xffffffff; } /* * Any init based on sequence numbers * should be done in the deferred init path * since we can be CLOSED and not have them * inited when rack_init() is called. We * are not closed so lets call it. */ rack_deferred_init(tp, rack); } if ((tp->t_state != TCPS_CLOSED) && (tp->t_state != TCPS_TIME_WAIT) && (no_query == 0) && (tp->snd_una != tp->snd_max)) { err = rack_init_outstanding(tp, rack, us_cts, *ptr); if (err) { *ptr = NULL; return(err); } } rack_stop_all_timers(tp, rack); /* Setup all the t_flags2 */ if (rack->r_mbuf_queue || rack->rc_always_pace || rack->r_use_cmp_ack) tp->t_flags2 |= TF2_SUPPORTS_MBUFQ; else tp->t_flags2 &= ~TF2_SUPPORTS_MBUFQ; if (rack->r_use_cmp_ack && TCPS_HAVEESTABLISHED(tp->t_state)) tp->t_flags2 |= TF2_MBUF_ACKCMP; /* * Timers in Rack are kept in microseconds so lets * convert any initial incoming variables * from ticks into usecs. Note that we * also change the values of t_srtt and t_rttvar, if * they are non-zero. They are kept with a 5 * bit decimal so we have to carefully convert * these to get the full precision. */ rack_convert_rtts(tp); rack_log_hystart_event(rack, rack->r_ctl.roundends, 20); if ((tptoinpcb(tp)->inp_flags & INP_DROPPED) == 0) { /* We do not start any timers on DROPPED connections */ if (tp->t_fb->tfb_chg_query == NULL) { rack_start_hpts_timer(rack, tp, tcp_get_usecs(NULL), 0, 0, 0); } else { struct tcp_query_resp qr; int ret; memset(&qr, 0, sizeof(qr)); /* Get the misc time stamps and such for rack */ qr.req = TCP_QUERY_RACK_TIMES; ret = (*tp->t_fb->tfb_chg_query)(tp, &qr); if (ret == 1) { rack->r_ctl.rc_reorder_ts = qr.rack_reorder_ts; rack->r_ctl.num_dsack = qr.rack_num_dsacks; rack->r_ctl.rc_tlp_rxt_last_time = qr.rack_rxt_last_time; rack->r_ctl.rc_rack_min_rtt = qr.rack_min_rtt; rack->rc_rack_rtt = qr.rack_rtt; rack->r_ctl.rc_rack_tmit_time = qr.rack_tmit_time; rack->r_ctl.rc_sacked = qr.rack_sacked; rack->r_ctl.rc_holes_rxt = qr.rack_holes_rxt; rack->r_ctl.rc_prr_delivered = qr.rack_prr_delivered; rack->r_ctl.rc_prr_recovery_fs = qr.rack_prr_recovery_fs; rack->r_ctl.rc_prr_sndcnt = qr.rack_prr_sndcnt; rack->r_ctl.rc_prr_out = qr.rack_prr_out; if (qr.rack_tlp_out) { rack->rc_tlp_in_progress = 1; rack->r_ctl.rc_tlp_cnt_out = qr.rack_tlp_cnt_out; } else { rack->rc_tlp_in_progress = 0; rack->r_ctl.rc_tlp_cnt_out = 0; } if (qr.rack_srtt_measured) rack->rc_srtt_measure_made = 1; if (qr.rack_in_persist == 1) { rack->r_ctl.rc_went_idle_time = qr.rack_time_went_idle; #ifdef NETFLIX_SHARED_CWND if (rack->r_ctl.rc_scw) { tcp_shared_cwnd_idle(rack->r_ctl.rc_scw, rack->r_ctl.rc_scw_index); rack->rack_scwnd_is_idle = 1; } #endif rack->r_ctl.persist_lost_ends = 0; rack->probe_not_answered = 0; rack->forced_ack = 0; tp->t_rxtshift = 0; rack->rc_in_persist = 1; RACK_TCPT_RANGESET(tp->t_rxtcur, RACK_REXMTVAL(tp), rack_rto_min, rack_rto_max, rack->r_ctl.timer_slop); } if (qr.rack_wanted_output) rack->r_wanted_output = 1; rack_log_chg_info(tp, rack, 6, qr.rack_min_rtt, qr.rack_rtt, qr.rack_reorder_ts); } /* Get the old stack timers */ qr.req_param = 0; qr.req = TCP_QUERY_TIMERS_UP; ret = (*tp->t_fb->tfb_chg_query)(tp, &qr); if (ret) { /* * non-zero return means we have a timer('s) * to start. Zero means no timer (no keepalive * I suppose). */ uint32_t tov = 0; rack->r_ctl.rc_hpts_flags = qr.timer_hpts_flags; if (qr.timer_hpts_flags & PACE_PKT_OUTPUT) { rack->r_ctl.rc_last_output_to = qr.timer_pacing_to; if (TSTMP_GT(qr.timer_pacing_to, us_cts)) tov = qr.timer_pacing_to - us_cts; else tov = HPTS_TICKS_PER_SLOT; } if (qr.timer_hpts_flags & PACE_TMR_MASK) { rack->r_ctl.rc_timer_exp = qr.timer_timer_exp; if (tov == 0) { if (TSTMP_GT(qr.timer_timer_exp, us_cts)) tov = qr.timer_timer_exp - us_cts; else tov = HPTS_TICKS_PER_SLOT; } } rack_log_chg_info(tp, rack, 4, rack->r_ctl.rc_hpts_flags, rack->r_ctl.rc_last_output_to, rack->r_ctl.rc_timer_exp); if (tov) { struct hpts_diag diag; (void)tcp_hpts_insert_diag(tp, HPTS_USEC_TO_SLOTS(tov), __LINE__, &diag); rack_log_hpts_diag(rack, us_cts, &diag, &rack->r_ctl.act_rcv_time); } } } rack_log_rtt_shrinks(rack, us_cts, tp->t_rxtcur, __LINE__, RACK_RTTS_INIT); } return (0); } static int rack_handoff_ok(struct tcpcb *tp) { if ((tp->t_state == TCPS_CLOSED) || (tp->t_state == TCPS_LISTEN)) { /* Sure no problem though it may not stick */ return (0); } if ((tp->t_state == TCPS_SYN_SENT) || (tp->t_state == TCPS_SYN_RECEIVED)) { /* * We really don't know if you support sack, * you have to get to ESTAB or beyond to tell. */ return (EAGAIN); } if ((tp->t_flags & TF_SENTFIN) && ((tp->snd_max - tp->snd_una) > 1)) { /* * Rack will only send a FIN after all data is acknowledged. * So in this case we have more data outstanding. We can't * switch stacks until either all data and only the FIN * is left (in which case rack_init() now knows how * to deal with that) all is acknowledged and we * are only left with incoming data, though why you * would want to switch to rack after all data is acknowledged * I have no idea (rrs)! */ return (EAGAIN); } if ((tp->t_flags & TF_SACK_PERMIT) || rack_sack_not_required){ return (0); } /* * If we reach here we don't do SACK on this connection so we can * never do rack. */ return (EINVAL); } static void rack_fini(struct tcpcb *tp, int32_t tcb_is_purged) { if (tp->t_fb_ptr) { uint32_t cnt_free = 0; struct tcp_rack *rack; struct rack_sendmap *rsm; tcp_handle_orphaned_packets(tp); tp->t_flags &= ~TF_FORCEDATA; rack = (struct tcp_rack *)tp->t_fb_ptr; rack_log_pacing_delay_calc(rack, 0, 0, 0, rack_get_gp_est(rack), /* delRate */ rack_get_lt_bw(rack), /* rttProp */ 20, __LINE__, NULL, 0); #ifdef NETFLIX_SHARED_CWND if (rack->r_ctl.rc_scw) { uint32_t limit; if (rack->r_limit_scw) limit = max(1, rack->r_ctl.rc_lowest_us_rtt); else limit = 0; tcp_shared_cwnd_free_full(tp, rack->r_ctl.rc_scw, rack->r_ctl.rc_scw_index, limit); rack->r_ctl.rc_scw = NULL; } #endif if (rack->r_ctl.fsb.tcp_ip_hdr) { free(rack->r_ctl.fsb.tcp_ip_hdr, M_TCPFSB); rack->r_ctl.fsb.tcp_ip_hdr = NULL; rack->r_ctl.fsb.th = NULL; } if (rack->rc_always_pace) { tcp_decrement_paced_conn(); rack_undo_cc_pacing(rack); rack->rc_always_pace = 0; } /* Clean up any options if they were not applied */ while (!TAILQ_EMPTY(&rack->r_ctl.opt_list)) { struct deferred_opt_list *dol; dol = TAILQ_FIRST(&rack->r_ctl.opt_list); TAILQ_REMOVE(&rack->r_ctl.opt_list, dol, next); free(dol, M_TCPDO); } /* rack does not use force data but other stacks may clear it */ if (rack->r_ctl.crte != NULL) { tcp_rel_pacing_rate(rack->r_ctl.crte, tp); rack->rack_hdrw_pacing = 0; rack->r_ctl.crte = NULL; } #ifdef TCP_BLACKBOX tcp_log_flowend(tp); #endif /* * Lets take a different approach to purging just * get each one and free it like a cum-ack would and * not use a foreach loop. */ rsm = tqhash_min(rack->r_ctl.tqh); while (rsm) { tqhash_remove(rack->r_ctl.tqh, rsm, REMOVE_TYPE_CUMACK); rack->r_ctl.rc_num_maps_alloced--; uma_zfree(rack_zone, rsm); rsm = tqhash_min(rack->r_ctl.tqh); } rsm = TAILQ_FIRST(&rack->r_ctl.rc_free); while (rsm) { TAILQ_REMOVE(&rack->r_ctl.rc_free, rsm, r_tnext); rack->r_ctl.rc_num_maps_alloced--; rack->rc_free_cnt--; cnt_free++; uma_zfree(rack_zone, rsm); rsm = TAILQ_FIRST(&rack->r_ctl.rc_free); } if ((rack->r_ctl.rc_num_maps_alloced > 0) && (tcp_bblogging_on(tp))) { union tcp_log_stackspecific log; struct timeval tv; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.flex8 = 10; log.u_bbr.flex1 = rack->r_ctl.rc_num_maps_alloced; log.u_bbr.flex2 = rack->rc_free_cnt; log.u_bbr.flex3 = cnt_free; log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); rsm = tqhash_min(rack->r_ctl.tqh); log.u_bbr.delRate = (uint64_t)rsm; rsm = TAILQ_FIRST(&rack->r_ctl.rc_free); log.u_bbr.cur_del_rate = (uint64_t)rsm; log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.pkt_epoch = __LINE__; (void)tcp_log_event(tp, NULL, NULL, NULL, TCP_LOG_OUT, ERRNO_UNK, 0, &log, false, NULL, NULL, 0, &tv); } KASSERT((rack->r_ctl.rc_num_maps_alloced == 0), ("rack:%p num_aloc:%u after freeing all?", rack, rack->r_ctl.rc_num_maps_alloced)); rack->rc_free_cnt = 0; free(rack->r_ctl.tqh, M_TCPFSB); rack->r_ctl.tqh = NULL; uma_zfree(rack_pcb_zone, tp->t_fb_ptr); tp->t_fb_ptr = NULL; } /* Make sure snd_nxt is correctly set */ tp->snd_nxt = tp->snd_max; } static void rack_set_state(struct tcpcb *tp, struct tcp_rack *rack) { if ((rack->r_state == TCPS_CLOSED) && (tp->t_state != TCPS_CLOSED)) { rack->r_is_v6 = (tptoinpcb(tp)->inp_vflag & INP_IPV6) != 0; } switch (tp->t_state) { case TCPS_SYN_SENT: rack->r_state = TCPS_SYN_SENT; rack->r_substate = rack_do_syn_sent; break; case TCPS_SYN_RECEIVED: rack->r_state = TCPS_SYN_RECEIVED; rack->r_substate = rack_do_syn_recv; break; case TCPS_ESTABLISHED: rack_set_pace_segments(tp, rack, __LINE__, NULL); rack->r_state = TCPS_ESTABLISHED; rack->r_substate = rack_do_established; break; case TCPS_CLOSE_WAIT: rack->r_state = TCPS_CLOSE_WAIT; rack->r_substate = rack_do_close_wait; break; case TCPS_FIN_WAIT_1: rack_set_pace_segments(tp, rack, __LINE__, NULL); rack->r_state = TCPS_FIN_WAIT_1; rack->r_substate = rack_do_fin_wait_1; break; case TCPS_CLOSING: rack_set_pace_segments(tp, rack, __LINE__, NULL); rack->r_state = TCPS_CLOSING; rack->r_substate = rack_do_closing; break; case TCPS_LAST_ACK: rack_set_pace_segments(tp, rack, __LINE__, NULL); rack->r_state = TCPS_LAST_ACK; rack->r_substate = rack_do_lastack; break; case TCPS_FIN_WAIT_2: rack->r_state = TCPS_FIN_WAIT_2; rack->r_substate = rack_do_fin_wait_2; break; case TCPS_LISTEN: case TCPS_CLOSED: case TCPS_TIME_WAIT: default: break; }; if (rack->r_use_cmp_ack && TCPS_HAVEESTABLISHED(tp->t_state)) rack->rc_tp->t_flags2 |= TF2_MBUF_ACKCMP; } static void rack_timer_audit(struct tcpcb *tp, struct tcp_rack *rack, struct sockbuf *sb) { /* * We received an ack, and then did not * call send or were bounced out due to the * hpts was running. Now a timer is up as well, is * it the right timer? */ struct rack_sendmap *rsm; int tmr_up; tmr_up = rack->r_ctl.rc_hpts_flags & PACE_TMR_MASK; if (rack->rc_in_persist && (tmr_up == PACE_TMR_PERSIT)) return; rsm = TAILQ_FIRST(&rack->r_ctl.rc_tmap); if (((rsm == NULL) || (tp->t_state < TCPS_ESTABLISHED)) && (tmr_up == PACE_TMR_RXT)) { /* Should be an RXT */ return; } if (rsm == NULL) { /* Nothing outstanding? */ if (tp->t_flags & TF_DELACK) { if (tmr_up == PACE_TMR_DELACK) /* We are supposed to have delayed ack up and we do */ return; } else if (sbavail(&tptosocket(tp)->so_snd) && (tmr_up == PACE_TMR_RXT)) { /* * if we hit enobufs then we would expect the possibility * of nothing outstanding and the RXT up (and the hptsi timer). */ return; } else if (((V_tcp_always_keepalive || rack->rc_inp->inp_socket->so_options & SO_KEEPALIVE) && (tp->t_state <= TCPS_CLOSING)) && (tmr_up == PACE_TMR_KEEP) && (tp->snd_max == tp->snd_una)) { /* We should have keep alive up and we do */ return; } } if (SEQ_GT(tp->snd_max, tp->snd_una) && ((tmr_up == PACE_TMR_TLP) || (tmr_up == PACE_TMR_RACK) || (tmr_up == PACE_TMR_RXT))) { /* * Either a Rack, TLP or RXT is fine if we * have outstanding data. */ return; } else if (tmr_up == PACE_TMR_DELACK) { /* * If the delayed ack was going to go off * before the rtx/tlp/rack timer were going to * expire, then that would be the timer in control. * Note we don't check the time here trusting the * code is correct. */ return; } /* * Ok the timer originally started is not what we want now. * We will force the hpts to be stopped if any, and restart * with the slot set to what was in the saved slot. */ if (tcp_in_hpts(rack->rc_tp)) { if (rack->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) { uint32_t us_cts; us_cts = tcp_get_usecs(NULL); if (TSTMP_GT(rack->r_ctl.rc_last_output_to, us_cts)) { rack->r_early = 1; rack->r_ctl.rc_agg_early += (rack->r_ctl.rc_last_output_to - us_cts); } rack->r_ctl.rc_hpts_flags &= ~PACE_PKT_OUTPUT; } tcp_hpts_remove(rack->rc_tp); } rack_timer_cancel(tp, rack, rack->r_ctl.rc_rcvtime, __LINE__); rack_start_hpts_timer(rack, tp, tcp_get_usecs(NULL), 0, 0, 0); } static void rack_do_win_updates(struct tcpcb *tp, struct tcp_rack *rack, uint32_t tiwin, uint32_t seq, uint32_t ack, uint32_t cts) { if ((SEQ_LT(tp->snd_wl1, seq) || (tp->snd_wl1 == seq && (SEQ_LT(tp->snd_wl2, ack) || (tp->snd_wl2 == ack && tiwin > tp->snd_wnd))))) { /* keep track of pure window updates */ if ((tp->snd_wl2 == ack) && (tiwin > tp->snd_wnd)) KMOD_TCPSTAT_INC(tcps_rcvwinupd); tp->snd_wnd = tiwin; rack_validate_fo_sendwin_up(tp, rack); tp->snd_wl1 = seq; tp->snd_wl2 = ack; if (tp->snd_wnd > tp->max_sndwnd) tp->max_sndwnd = tp->snd_wnd; rack->r_wanted_output = 1; } else if ((tp->snd_wl2 == ack) && (tiwin < tp->snd_wnd)) { tp->snd_wnd = tiwin; rack_validate_fo_sendwin_up(tp, rack); tp->snd_wl1 = seq; tp->snd_wl2 = ack; } else { /* Not a valid win update */ return; } if (tp->snd_wnd > tp->max_sndwnd) tp->max_sndwnd = tp->snd_wnd; /* Do we exit persists? */ if ((rack->rc_in_persist != 0) && (tp->snd_wnd >= min((rack->r_ctl.rc_high_rwnd/2), rack->r_ctl.rc_pace_min_segs))) { rack_exit_persist(tp, rack, cts); } /* Do we enter persists? */ if ((rack->rc_in_persist == 0) && (tp->snd_wnd < min((rack->r_ctl.rc_high_rwnd/2), rack->r_ctl.rc_pace_min_segs)) && TCPS_HAVEESTABLISHED(tp->t_state) && ((tp->snd_max == tp->snd_una) || rack->rc_has_collapsed) && sbavail(&tptosocket(tp)->so_snd) && (sbavail(&tptosocket(tp)->so_snd) > tp->snd_wnd)) { /* * Here the rwnd is less than * the pacing size, we are established, * nothing is outstanding, and there is * data to send. Enter persists. */ rack_enter_persist(tp, rack, rack->r_ctl.rc_rcvtime, ack); } } static void rack_log_input_packet(struct tcpcb *tp, struct tcp_rack *rack, struct tcp_ackent *ae, int ackval, uint32_t high_seq) { if (tcp_bblogging_on(rack->rc_tp)) { struct inpcb *inp = tptoinpcb(tp); union tcp_log_stackspecific log; struct timeval ltv; char tcp_hdr_buf[60]; struct tcphdr *th; struct timespec ts; uint32_t orig_snd_una; uint8_t xx = 0; #ifdef TCP_REQUEST_TRK struct tcp_sendfile_track *tcp_req; if (SEQ_GT(ae->ack, tp->snd_una)) { tcp_req = tcp_req_find_req_for_seq(tp, (ae->ack-1)); } else { tcp_req = tcp_req_find_req_for_seq(tp, ae->ack); } #endif memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.inhpts = tcp_in_hpts(rack->rc_tp); if (rack->rack_no_prr == 0) log.u_bbr.flex1 = rack->r_ctl.rc_prr_sndcnt; else log.u_bbr.flex1 = 0; log.u_bbr.use_lt_bw = rack->r_ent_rec_ns; log.u_bbr.use_lt_bw <<= 1; log.u_bbr.use_lt_bw |= rack->r_might_revert; log.u_bbr.flex2 = rack->r_ctl.rc_num_maps_alloced; log.u_bbr.bbr_state = rack->rc_free_cnt; log.u_bbr.inflight = ctf_flight_size(tp, rack->r_ctl.rc_sacked); log.u_bbr.pkts_out = tp->t_maxseg; log.u_bbr.flex4 = rack->r_ctl.rc_hpts_flags; log.u_bbr.flex7 = 1; log.u_bbr.lost = ae->flags; log.u_bbr.cwnd_gain = ackval; log.u_bbr.pacing_gain = 0x2; if (ae->flags & TSTMP_HDWR) { /* Record the hardware timestamp if present */ log.u_bbr.flex3 = M_TSTMP; ts.tv_sec = ae->timestamp / 1000000000; ts.tv_nsec = ae->timestamp % 1000000000; ltv.tv_sec = ts.tv_sec; ltv.tv_usec = ts.tv_nsec / 1000; log.u_bbr.lt_epoch = tcp_tv_to_usectick(<v); } else if (ae->flags & TSTMP_LRO) { /* Record the LRO the arrival timestamp */ log.u_bbr.flex3 = M_TSTMP_LRO; ts.tv_sec = ae->timestamp / 1000000000; ts.tv_nsec = ae->timestamp % 1000000000; ltv.tv_sec = ts.tv_sec; ltv.tv_usec = ts.tv_nsec / 1000; log.u_bbr.flex5 = tcp_tv_to_usectick(<v); } log.u_bbr.timeStamp = tcp_get_usecs(<v); /* Log the rcv time */ log.u_bbr.delRate = ae->timestamp; #ifdef TCP_REQUEST_TRK log.u_bbr.applimited = tp->t_tcpreq_closed; log.u_bbr.applimited <<= 8; log.u_bbr.applimited |= tp->t_tcpreq_open; log.u_bbr.applimited <<= 8; log.u_bbr.applimited |= tp->t_tcpreq_req; if (tcp_req) { /* Copy out any client req info */ /* seconds */ log.u_bbr.pkt_epoch = (tcp_req->localtime / HPTS_USEC_IN_SEC); /* useconds */ log.u_bbr.delivered = (tcp_req->localtime % HPTS_USEC_IN_SEC); log.u_bbr.rttProp = tcp_req->timestamp; log.u_bbr.cur_del_rate = tcp_req->start; if (tcp_req->flags & TCP_TRK_TRACK_FLG_OPEN) { log.u_bbr.flex8 |= 1; } else { log.u_bbr.flex8 |= 2; log.u_bbr.bw_inuse = tcp_req->end; } log.u_bbr.flex6 = tcp_req->start_seq; if (tcp_req->flags & TCP_TRK_TRACK_FLG_COMP) { log.u_bbr.flex8 |= 4; log.u_bbr.epoch = tcp_req->end_seq; } } #endif memset(tcp_hdr_buf, 0, sizeof(tcp_hdr_buf)); th = (struct tcphdr *)tcp_hdr_buf; th->th_seq = ae->seq; th->th_ack = ae->ack; th->th_win = ae->win; /* Now fill in the ports */ th->th_sport = inp->inp_fport; th->th_dport = inp->inp_lport; tcp_set_flags(th, ae->flags); /* Now do we have a timestamp option? */ if (ae->flags & HAS_TSTMP) { u_char *cp; uint32_t val; th->th_off = ((sizeof(struct tcphdr) + TCPOLEN_TSTAMP_APPA) >> 2); cp = (u_char *)(th + 1); *cp = TCPOPT_NOP; cp++; *cp = TCPOPT_NOP; cp++; *cp = TCPOPT_TIMESTAMP; cp++; *cp = TCPOLEN_TIMESTAMP; cp++; val = htonl(ae->ts_value); bcopy((char *)&val, (char *)cp, sizeof(uint32_t)); val = htonl(ae->ts_echo); bcopy((char *)&val, (char *)(cp + 4), sizeof(uint32_t)); } else th->th_off = (sizeof(struct tcphdr) >> 2); /* * For sane logging we need to play a little trick. * If the ack were fully processed we would have moved * snd_una to high_seq, but since compressed acks are * processed in two phases, at this point (logging) snd_una * won't be advanced. So we would see multiple acks showing * the advancement. We can prevent that by "pretending" that * snd_una was advanced and then un-advancing it so that the * logging code has the right value for tlb_snd_una. */ if (tp->snd_una != high_seq) { orig_snd_una = tp->snd_una; tp->snd_una = high_seq; xx = 1; } else xx = 0; TCP_LOG_EVENTP(tp, th, &tptosocket(tp)->so_rcv, &tptosocket(tp)->so_snd, TCP_LOG_IN, 0, 0, &log, true, <v); if (xx) { tp->snd_una = orig_snd_una; } } } static void rack_handle_probe_response(struct tcp_rack *rack, uint32_t tiwin, uint32_t us_cts) { uint32_t us_rtt; /* * A persist or keep-alive was forced out, update our * min rtt time. Note now worry about lost responses. * When a subsequent keep-alive or persist times out * and forced_ack is still on, then the last probe * was not responded to. In such cases we have a * sysctl that controls the behavior. Either we apply * the rtt but with reduced confidence (0). Or we just * plain don't apply the rtt estimate. Having data flow * will clear the probe_not_answered flag i.e. cum-ack * move forward exiting and reentering persists. */ rack->forced_ack = 0; rack->rc_tp->t_rxtshift = 0; if ((rack->rc_in_persist && (tiwin == rack->rc_tp->snd_wnd)) || (rack->rc_in_persist == 0)) { /* * In persists only apply the RTT update if this is * a response to our window probe. And that * means the rwnd sent must match the current * snd_wnd. If it does not, then we got a * window update ack instead. For keepalive * we allow the answer no matter what the window. * * Note that if the probe_not_answered is set then * the forced_ack_ts is the oldest one i.e. the first * probe sent that might have been lost. This assures * us that if we do calculate an RTT it is longer not * some short thing. */ if (rack->rc_in_persist) counter_u64_add(rack_persists_acks, 1); us_rtt = us_cts - rack->r_ctl.forced_ack_ts; if (us_rtt == 0) us_rtt = 1; if (rack->probe_not_answered == 0) { rack_apply_updated_usrtt(rack, us_rtt, us_cts); tcp_rack_xmit_timer(rack, us_rtt, 0, us_rtt, 3, NULL, 1); } else { /* We have a retransmitted probe here too */ if (rack_apply_rtt_with_reduced_conf) { rack_apply_updated_usrtt(rack, us_rtt, us_cts); tcp_rack_xmit_timer(rack, us_rtt, 0, us_rtt, 0, NULL, 1); } } } } static int rack_do_compressed_ack_processing(struct tcpcb *tp, struct socket *so, struct mbuf *m, int nxt_pkt, struct timeval *tv) { /* * Handle a "special" compressed ack mbuf. Each incoming * ack has only four possible dispositions: * * A) It moves the cum-ack forward * B) It is behind the cum-ack. * C) It is a window-update ack. * D) It is a dup-ack. * * Note that we can have between 1 -> TCP_COMP_ACK_ENTRIES * in the incoming mbuf. We also need to still pay attention * to nxt_pkt since there may be another packet after this * one. */ #ifdef TCP_ACCOUNTING uint64_t ts_val; uint64_t rdstc; #endif int segsiz; struct timespec ts; struct tcp_rack *rack; struct tcp_ackent *ae; uint32_t tiwin, ms_cts, cts, acked, acked_amount, high_seq, win_seq, the_win, win_upd_ack; int cnt, i, did_out, ourfinisacked = 0; struct tcpopt to_holder, *to = NULL; #ifdef TCP_ACCOUNTING int win_up_req = 0; #endif int nsegs = 0; int under_pacing = 0; int recovery = 0; #ifdef TCP_ACCOUNTING sched_pin(); #endif rack = (struct tcp_rack *)tp->t_fb_ptr; if (rack->gp_ready && (rack->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT)) under_pacing = 1; if (rack->r_state != tp->t_state) rack_set_state(tp, rack); if ((tp->t_state >= TCPS_FIN_WAIT_1) && (tp->t_flags & TF_GPUTINPROG)) { /* * We have a goodput in progress * and we have entered a late state. * Do we have enough data in the sb * to handle the GPUT request? */ uint32_t bytes; bytes = tp->gput_ack - tp->gput_seq; if (SEQ_GT(tp->gput_seq, tp->snd_una)) bytes += tp->gput_seq - tp->snd_una; if (bytes > sbavail(&tptosocket(tp)->so_snd)) { /* * There are not enough bytes in the socket * buffer that have been sent to cover this * measurement. Cancel it. */ rack_log_pacing_delay_calc(rack, (tp->gput_ack - tp->gput_seq) /*flex2*/, rack->r_ctl.rc_gp_srtt /*flex1*/, tp->gput_seq, 0, 0, 18, __LINE__, NULL, 0); tp->t_flags &= ~TF_GPUTINPROG; } } to = &to_holder; to->to_flags = 0; KASSERT((m->m_len >= sizeof(struct tcp_ackent)), ("tp:%p m_cmpack:%p with invalid len:%u", tp, m, m->m_len)); cnt = m->m_len / sizeof(struct tcp_ackent); counter_u64_add(rack_multi_single_eq, cnt); high_seq = tp->snd_una; the_win = tp->snd_wnd; win_seq = tp->snd_wl1; win_upd_ack = tp->snd_wl2; cts = tcp_tv_to_usectick(tv); ms_cts = tcp_tv_to_mssectick(tv); rack->r_ctl.rc_rcvtime = cts; segsiz = ctf_fixed_maxseg(tp); if ((rack->rc_gp_dyn_mul) && (rack->use_fixed_rate == 0) && (rack->rc_always_pace)) { /* Check in on probertt */ rack_check_probe_rtt(rack, cts); } for (i = 0; i < cnt; i++) { #ifdef TCP_ACCOUNTING ts_val = get_cyclecount(); #endif rack_clear_rate_sample(rack); ae = ((mtod(m, struct tcp_ackent *)) + i); if (ae->flags & TH_FIN) rack_log_pacing_delay_calc(rack, 0, 0, 0, rack_get_gp_est(rack), /* delRate */ rack_get_lt_bw(rack), /* rttProp */ 20, __LINE__, NULL, 0); /* Setup the window */ tiwin = ae->win << tp->snd_scale; if (tiwin > rack->r_ctl.rc_high_rwnd) rack->r_ctl.rc_high_rwnd = tiwin; /* figure out the type of ack */ if (SEQ_LT(ae->ack, high_seq)) { /* Case B*/ ae->ack_val_set = ACK_BEHIND; } else if (SEQ_GT(ae->ack, high_seq)) { /* Case A */ ae->ack_val_set = ACK_CUMACK; } else if ((tiwin == the_win) && (rack->rc_in_persist == 0)){ /* Case D */ ae->ack_val_set = ACK_DUPACK; } else { /* Case C */ ae->ack_val_set = ACK_RWND; } if (rack->sack_attack_disable > 0) { rack_log_type_bbrsnd(rack, 0, 0, cts, tv, __LINE__); rack->r_ctl.ack_during_sd++; } rack_log_input_packet(tp, rack, ae, ae->ack_val_set, high_seq); /* Validate timestamp */ if (ae->flags & HAS_TSTMP) { /* Setup for a timestamp */ to->to_flags = TOF_TS; ae->ts_echo -= tp->ts_offset; to->to_tsecr = ae->ts_echo; to->to_tsval = ae->ts_value; /* * If echoed timestamp is later than the current time, fall back to * non RFC1323 RTT calculation. Normalize timestamp if syncookies * were used when this connection was established. */ if (TSTMP_GT(ae->ts_echo, ms_cts)) to->to_tsecr = 0; if (tp->ts_recent && TSTMP_LT(ae->ts_value, tp->ts_recent)) { if (ctf_ts_check_ac(tp, (ae->flags & 0xff))) { #ifdef TCP_ACCOUNTING rdstc = get_cyclecount(); if (rdstc > ts_val) { if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_proc_time[ae->ack_val_set] += (rdstc - ts_val); } } #endif continue; } } if (SEQ_LEQ(ae->seq, tp->last_ack_sent) && SEQ_LEQ(tp->last_ack_sent, ae->seq)) { tp->ts_recent_age = tcp_ts_getticks(); tp->ts_recent = ae->ts_value; } } else { /* Setup for a no options */ to->to_flags = 0; } /* Update the rcv time and perform idle reduction possibly */ if (tp->t_idle_reduce && (tp->snd_max == tp->snd_una) && (TICKS_2_USEC(ticks - tp->t_rcvtime) >= tp->t_rxtcur)) { counter_u64_add(rack_input_idle_reduces, 1); rack_cc_after_idle(rack, tp); } tp->t_rcvtime = ticks; /* Now what about ECN of a chain of pure ACKs? */ if (tcp_ecn_input_segment(tp, ae->flags, 0, tcp_packets_this_ack(tp, ae->ack), ae->codepoint)) rack_cong_signal(tp, CC_ECN, ae->ack, __LINE__); #ifdef TCP_ACCOUNTING /* Count for the specific type of ack in */ if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[ae->ack_val_set]++; } #endif /* * Note how we could move up these in the determination * above, but we don't so that way the timestamp checks (and ECN) * is done first before we do any processing on the ACK. * The non-compressed path through the code has this * weakness (noted by @jtl) that it actually does some * processing before verifying the timestamp information. * We don't take that path here which is why we set * the ack_val_set first, do the timestamp and ecn * processing, and then look at what we have setup. */ if (ae->ack_val_set == ACK_BEHIND) { /* * Case B flag reordering, if window is not closed * or it could be a keep-alive or persists */ if (SEQ_LT(ae->ack, tp->snd_una) && (sbspace(&so->so_rcv) > segsiz)) { rack->r_ctl.rc_reorder_ts = tcp_tv_to_usectick(&rack->r_ctl.act_rcv_time); if (rack->r_ctl.rc_reorder_ts == 0) rack->r_ctl.rc_reorder_ts = 1; } } else if (ae->ack_val_set == ACK_DUPACK) { /* Case D */ rack_strike_dupack(rack); } else if (ae->ack_val_set == ACK_RWND) { /* Case C */ if ((ae->flags & TSTMP_LRO) || (ae->flags & TSTMP_HDWR)) { ts.tv_sec = ae->timestamp / 1000000000; ts.tv_nsec = ae->timestamp % 1000000000; rack->r_ctl.act_rcv_time.tv_sec = ts.tv_sec; rack->r_ctl.act_rcv_time.tv_usec = ts.tv_nsec/1000; } else { rack->r_ctl.act_rcv_time = *tv; } if (rack->forced_ack) { rack_handle_probe_response(rack, tiwin, tcp_tv_to_usectick(&rack->r_ctl.act_rcv_time)); } #ifdef TCP_ACCOUNTING win_up_req = 1; #endif win_upd_ack = ae->ack; win_seq = ae->seq; the_win = tiwin; rack_do_win_updates(tp, rack, the_win, win_seq, win_upd_ack, cts); } else { /* Case A */ if (SEQ_GT(ae->ack, tp->snd_max)) { /* * We just send an ack since the incoming * ack is beyond the largest seq we sent. */ if ((tp->t_flags & TF_ACKNOW) == 0) { ctf_ack_war_checks(tp, &rack->r_ctl.challenge_ack_ts, &rack->r_ctl.challenge_ack_cnt); if (tp->t_flags && TF_ACKNOW) rack->r_wanted_output = 1; } } else { nsegs++; /* If the window changed setup to update */ if (tiwin != tp->snd_wnd) { win_upd_ack = ae->ack; win_seq = ae->seq; the_win = tiwin; rack_do_win_updates(tp, rack, the_win, win_seq, win_upd_ack, cts); } #ifdef TCP_ACCOUNTING /* Account for the acks */ if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[CNT_OF_ACKS_IN] += (((ae->ack - high_seq) + segsiz - 1) / segsiz); } #endif high_seq = ae->ack; if (rack_verbose_logging && tcp_bblogging_on(rack->rc_tp)) rack_log_hystart_event(rack, high_seq, 8); /* Setup our act_rcv_time */ if ((ae->flags & TSTMP_LRO) || (ae->flags & TSTMP_HDWR)) { ts.tv_sec = ae->timestamp / 1000000000; ts.tv_nsec = ae->timestamp % 1000000000; rack->r_ctl.act_rcv_time.tv_sec = ts.tv_sec; rack->r_ctl.act_rcv_time.tv_usec = ts.tv_nsec/1000; } else { rack->r_ctl.act_rcv_time = *tv; } rack_process_to_cumack(tp, rack, ae->ack, cts, to, tcp_tv_to_lusectick(&rack->r_ctl.act_rcv_time)); #ifdef TCP_REQUEST_TRK rack_req_check_for_comp(rack, high_seq); #endif if (rack->rc_dsack_round_seen) { /* Is the dsack round over? */ if (SEQ_GEQ(ae->ack, rack->r_ctl.dsack_round_end)) { /* Yes it is */ rack->rc_dsack_round_seen = 0; rack_log_dsack_event(rack, 3, __LINE__, 0, 0); } } } } /* And lets be sure to commit the rtt measurements for this ack */ tcp_rack_xmit_timer_commit(rack, tp); #ifdef TCP_ACCOUNTING rdstc = get_cyclecount(); if (rdstc > ts_val) { if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_proc_time[ae->ack_val_set] += (rdstc - ts_val); if (ae->ack_val_set == ACK_CUMACK) tp->tcp_proc_time[CYC_HANDLE_MAP] += (rdstc - ts_val); } } #endif } #ifdef TCP_ACCOUNTING ts_val = get_cyclecount(); #endif /* Tend to any collapsed window */ if (SEQ_GT(tp->snd_max, high_seq) && (tp->snd_wnd < (tp->snd_max - high_seq))) { /* The peer collapsed the window */ rack_collapsed_window(rack, (tp->snd_max - high_seq), high_seq, __LINE__); } else if (rack->rc_has_collapsed) rack_un_collapse_window(rack, __LINE__); if ((rack->r_collapse_point_valid) && (SEQ_GT(high_seq, rack->r_ctl.high_collapse_point))) rack->r_collapse_point_valid = 0; acked_amount = acked = (high_seq - tp->snd_una); if (acked) { /* * The draft (v3) calls for us to use SEQ_GEQ, but that * causes issues when we are just going app limited. Lets * instead use SEQ_GT where its equal but more data * is outstanding. * * Also make sure we are on the last ack of a series. We * have to have all the ack's processed in queue to know * if there is something left outstanding. * */ if (SEQ_GEQ(high_seq, rack->r_ctl.roundends) && (rack->rc_new_rnd_needed == 0) && (nxt_pkt == 0)) { rack_log_hystart_event(rack, high_seq, 21); rack->r_ctl.current_round++; /* Force the next send to setup the next round */ rack->rc_new_rnd_needed = 1; if (CC_ALGO(tp)->newround != NULL) { CC_ALGO(tp)->newround(&tp->t_ccv, rack->r_ctl.current_round); } } /* * Clear the probe not answered flag * since cum-ack moved forward. */ rack->probe_not_answered = 0; if (rack->sack_attack_disable == 0) rack_do_decay(rack); if (acked >= segsiz) { /* * You only get credit for * MSS and greater (and you get extra * credit for larger cum-ack moves). */ int ac; ac = acked / segsiz; rack->r_ctl.ack_count += ac; counter_u64_add(rack_ack_total, ac); } if (rack->r_ctl.ack_count > 0xfff00000) { /* * reduce the number to keep us under * a uint32_t. */ rack->r_ctl.ack_count /= 2; rack->r_ctl.sack_count /= 2; } if (tp->t_flags & TF_NEEDSYN) { /* * T/TCP: Connection was half-synchronized, and our SYN has * been ACK'd (so connection is now fully synchronized). Go * to non-starred state, increment snd_una for ACK of SYN, * and check if we can do window scaling. */ tp->t_flags &= ~TF_NEEDSYN; tp->snd_una++; acked_amount = acked = (high_seq - tp->snd_una); } if (acked > sbavail(&so->so_snd)) acked_amount = sbavail(&so->so_snd); #ifdef TCP_SAD_DETECTION /* * We only care on a cum-ack move if we are in a sack-disabled * state. We have already added in to the ack_count, and we never * would disable on a cum-ack move, so we only care to do the * detection if it may "undo" it, i.e. we were in disabled already. */ if (rack->sack_attack_disable) rack_do_detection(tp, rack, acked_amount, segsiz); #endif if (IN_FASTRECOVERY(tp->t_flags) && (rack->rack_no_prr == 0)) rack_update_prr(tp, rack, acked_amount, high_seq); if (IN_RECOVERY(tp->t_flags)) { if (SEQ_LT(high_seq, tp->snd_recover) && (SEQ_LT(high_seq, tp->snd_max))) { tcp_rack_partialack(tp); } else { rack_post_recovery(tp, high_seq); recovery = 1; } } /* Handle the rack-log-ack part (sendmap) */ if ((sbused(&so->so_snd) == 0) && (acked > acked_amount) && (tp->t_state >= TCPS_FIN_WAIT_1) && (tp->t_flags & TF_SENTFIN)) { /* * We must be sure our fin * was sent and acked (we can be * in FIN_WAIT_1 without having * sent the fin). */ ourfinisacked = 1; /* * Lets make sure snd_una is updated * since most likely acked_amount = 0 (it * should be). */ tp->snd_una = high_seq; } /* Did we make a RTO error? */ if ((tp->t_flags & TF_PREVVALID) && ((tp->t_flags & TF_RCVD_TSTMP) == 0)) { tp->t_flags &= ~TF_PREVVALID; if (tp->t_rxtshift == 1 && (int)(ticks - tp->t_badrxtwin) < 0) rack_cong_signal(tp, CC_RTO_ERR, high_seq, __LINE__); } /* Handle the data in the socket buffer */ KMOD_TCPSTAT_ADD(tcps_rcvackpack, 1); KMOD_TCPSTAT_ADD(tcps_rcvackbyte, acked); if (acked_amount > 0) { struct mbuf *mfree; rack_ack_received(tp, rack, high_seq, nsegs, CC_ACK, recovery); SOCKBUF_LOCK(&so->so_snd); mfree = sbcut_locked(&so->so_snd, acked_amount); tp->snd_una = high_seq; /* Note we want to hold the sb lock through the sendmap adjust */ rack_adjust_sendmap_head(rack, &so->so_snd); /* Wake up the socket if we have room to write more */ rack_log_wakeup(tp,rack, &so->so_snd, acked, 2); sowwakeup_locked(so); if ((recovery == 1) && (rack->excess_rxt_on) && (rack->r_cwnd_was_clamped == 0)) { do_rack_excess_rxt(tp, rack); } else if (rack->r_cwnd_was_clamped) do_rack_check_for_unclamp(tp, rack); m_freem(mfree); } /* update progress */ tp->t_acktime = ticks; rack_log_progress_event(rack, tp, tp->t_acktime, PROGRESS_UPDATE, __LINE__); /* Clear out shifts and such */ tp->t_rxtshift = 0; RACK_TCPT_RANGESET(tp->t_rxtcur, RACK_REXMTVAL(tp), rack_rto_min, rack_rto_max, rack->r_ctl.timer_slop); rack->rc_tlp_in_progress = 0; rack->r_ctl.rc_tlp_cnt_out = 0; /* Send recover and snd_nxt must be dragged along */ if (SEQ_GT(tp->snd_una, tp->snd_recover)) tp->snd_recover = tp->snd_una; if (SEQ_LT(tp->snd_nxt, tp->snd_una)) tp->snd_nxt = tp->snd_una; /* * If the RXT timer is running we want to * stop it, so we can restart a TLP (or new RXT). */ if (rack->r_ctl.rc_hpts_flags & PACE_TMR_RXT) rack_timer_cancel(tp, rack, rack->r_ctl.rc_rcvtime, __LINE__); tp->snd_wl2 = high_seq; tp->t_dupacks = 0; if (under_pacing && (rack->use_fixed_rate == 0) && (rack->in_probe_rtt == 0) && rack->rc_gp_dyn_mul && rack->rc_always_pace) { /* Check if we are dragging bottom */ rack_check_bottom_drag(tp, rack, so); } if (tp->snd_una == tp->snd_max) { tp->t_flags &= ~TF_PREVVALID; rack->r_ctl.retran_during_recovery = 0; rack->rc_suspicious = 0; rack->r_ctl.dsack_byte_cnt = 0; rack->r_ctl.rc_went_idle_time = tcp_get_usecs(NULL); if (rack->r_ctl.rc_went_idle_time == 0) rack->r_ctl.rc_went_idle_time = 1; rack_log_progress_event(rack, tp, 0, PROGRESS_CLEAR, __LINE__); if (sbavail(&tptosocket(tp)->so_snd) == 0) tp->t_acktime = 0; /* Set so we might enter persists... */ rack->r_wanted_output = 1; rack_timer_cancel(tp, rack, rack->r_ctl.rc_rcvtime, __LINE__); sack_filter_clear(&rack->r_ctl.rack_sf, tp->snd_una); if ((tp->t_state >= TCPS_FIN_WAIT_1) && (sbavail(&so->so_snd) == 0) && (tp->t_flags2 & TF2_DROP_AF_DATA)) { /* * The socket was gone and the * peer sent data (not now in the past), time to * reset him. */ rack_timer_cancel(tp, rack, rack->r_ctl.rc_rcvtime, __LINE__); /* tcp_close will kill the inp pre-log the Reset */ tcp_log_end_status(tp, TCP_EI_STATUS_SERVER_RST); #ifdef TCP_ACCOUNTING rdstc = get_cyclecount(); if (rdstc > ts_val) { if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_proc_time[ACK_CUMACK] += (rdstc - ts_val); tp->tcp_proc_time[CYC_HANDLE_ACK] += (rdstc - ts_val); } } #endif m_freem(m); tp = tcp_close(tp); if (tp == NULL) { #ifdef TCP_ACCOUNTING sched_unpin(); #endif return (1); } /* * We would normally do drop-with-reset which would * send back a reset. We can't since we don't have * all the needed bits. Instead lets arrange for * a call to tcp_output(). That way since we * are in the closed state we will generate a reset. * * Note if tcp_accounting is on we don't unpin since * we do that after the goto label. */ goto send_out_a_rst; } if ((sbused(&so->so_snd) == 0) && (tp->t_state >= TCPS_FIN_WAIT_1) && (tp->t_flags & TF_SENTFIN)) { /* * If we can't receive any more data, then closing user can * proceed. Starting the timer is contrary to the * specification, but if we don't get a FIN we'll hang * forever. * */ if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { soisdisconnected(so); tcp_timer_activate(tp, TT_2MSL, (tcp_fast_finwait2_recycle ? tcp_finwait2_timeout : TP_MAXIDLE(tp))); } if (ourfinisacked == 0) { /* * We don't change to fin-wait-2 if we have our fin acked * which means we are probably in TCPS_CLOSING. */ tcp_state_change(tp, TCPS_FIN_WAIT_2); } } } /* Wake up the socket if we have room to write more */ if (sbavail(&so->so_snd)) { rack->r_wanted_output = 1; if (ctf_progress_timeout_check(tp, true)) { rack_log_progress_event((struct tcp_rack *)tp->t_fb_ptr, tp, tick, PROGRESS_DROP, __LINE__); /* * We cheat here and don't send a RST, we should send one * when the pacer drops the connection. */ #ifdef TCP_ACCOUNTING rdstc = get_cyclecount(); if (rdstc > ts_val) { if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_proc_time[ACK_CUMACK] += (rdstc - ts_val); tp->tcp_proc_time[CYC_HANDLE_ACK] += (rdstc - ts_val); } } sched_unpin(); #endif (void)tcp_drop(tp, ETIMEDOUT); m_freem(m); return (1); } } if (ourfinisacked) { switch(tp->t_state) { case TCPS_CLOSING: #ifdef TCP_ACCOUNTING rdstc = get_cyclecount(); if (rdstc > ts_val) { if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_proc_time[ACK_CUMACK] += (rdstc - ts_val); tp->tcp_proc_time[CYC_HANDLE_ACK] += (rdstc - ts_val); } } sched_unpin(); #endif tcp_twstart(tp); m_freem(m); return (1); break; case TCPS_LAST_ACK: #ifdef TCP_ACCOUNTING rdstc = get_cyclecount(); if (rdstc > ts_val) { if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_proc_time[ACK_CUMACK] += (rdstc - ts_val); tp->tcp_proc_time[CYC_HANDLE_ACK] += (rdstc - ts_val); } } sched_unpin(); #endif tp = tcp_close(tp); ctf_do_drop(m, tp); return (1); break; case TCPS_FIN_WAIT_1: #ifdef TCP_ACCOUNTING rdstc = get_cyclecount(); if (rdstc > ts_val) { if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_proc_time[ACK_CUMACK] += (rdstc - ts_val); tp->tcp_proc_time[CYC_HANDLE_ACK] += (rdstc - ts_val); } } #endif if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { soisdisconnected(so); tcp_timer_activate(tp, TT_2MSL, (tcp_fast_finwait2_recycle ? tcp_finwait2_timeout : TP_MAXIDLE(tp))); } tcp_state_change(tp, TCPS_FIN_WAIT_2); break; default: break; } } if (rack->r_fast_output) { /* * We re doing fast output.. can we expand that? */ rack_gain_for_fastoutput(rack, tp, so, acked_amount); } #ifdef TCP_ACCOUNTING rdstc = get_cyclecount(); if (rdstc > ts_val) { if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_proc_time[ACK_CUMACK] += (rdstc - ts_val); tp->tcp_proc_time[CYC_HANDLE_ACK] += (rdstc - ts_val); } } } else if (win_up_req) { rdstc = get_cyclecount(); if (rdstc > ts_val) { if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_proc_time[ACK_RWND] += (rdstc - ts_val); } } #endif } /* Now is there a next packet, if so we are done */ m_freem(m); did_out = 0; if (nxt_pkt) { #ifdef TCP_ACCOUNTING sched_unpin(); #endif rack_log_doseg_done(rack, cts, nxt_pkt, did_out, 5, nsegs); return (0); } rack_handle_might_revert(tp, rack); ctf_calc_rwin(so, tp); if ((rack->r_wanted_output != 0) || (rack->r_fast_output != 0)) { send_out_a_rst: if (tcp_output(tp) < 0) { #ifdef TCP_ACCOUNTING sched_unpin(); #endif return (1); } did_out = 1; } if (tp->t_flags2 & TF2_HPTS_CALLS) tp->t_flags2 &= ~TF2_HPTS_CALLS; rack_free_trim(rack); #ifdef TCP_ACCOUNTING sched_unpin(); #endif rack_timer_audit(tp, rack, &so->so_snd); rack_log_doseg_done(rack, cts, nxt_pkt, did_out, 6, nsegs); return (0); } #define TCP_LRO_TS_OPTION \ ntohl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | \ (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP) static int rack_do_segment_nounlock(struct tcpcb *tp, struct mbuf *m, struct tcphdr *th, int32_t drop_hdrlen, int32_t tlen, uint8_t iptos, int32_t nxt_pkt, struct timeval *tv) { struct inpcb *inp = tptoinpcb(tp); struct socket *so = tptosocket(tp); #ifdef TCP_ACCOUNTING uint64_t ts_val; #endif int32_t thflags, retval, did_out = 0; int32_t way_out = 0; /* * cts - is the current time from tv (caller gets ts) in microseconds. * ms_cts - is the current time from tv in milliseconds. * us_cts - is the time that LRO or hardware actually got the packet in microseconds. */ uint32_t cts, us_cts, ms_cts; uint32_t tiwin, high_seq; struct timespec ts; struct tcpopt to; struct tcp_rack *rack; struct rack_sendmap *rsm; int32_t prev_state = 0; int no_output = 0; int slot_remaining = 0; #ifdef TCP_ACCOUNTING int ack_val_set = 0xf; #endif int nsegs; NET_EPOCH_ASSERT(); INP_WLOCK_ASSERT(inp); /* * tv passed from common code is from either M_TSTMP_LRO or * tcp_get_usecs() if no LRO m_pkthdr timestamp is present. */ rack = (struct tcp_rack *)tp->t_fb_ptr; if (rack->rack_deferred_inited == 0) { /* * If we are the connecting socket we will * hit rack_init() when no sequence numbers * are setup. This makes it so we must defer * some initialization. Call that now. */ rack_deferred_init(tp, rack); } /* * Check to see if we need to skip any output plans. This * can happen in the non-LRO path where we are pacing and * must process the ack coming in but need to defer sending * anything becase a pacing timer is running. */ us_cts = tcp_tv_to_usectick(tv); if (m->m_flags & M_ACKCMP) { /* * All compressed ack's are ack's by definition so * remove any ack required flag and then do the processing. */ rack->rc_ack_required = 0; return (rack_do_compressed_ack_processing(tp, so, m, nxt_pkt, tv)); } thflags = tcp_get_flags(th); if ((rack->rc_always_pace == 1) && (rack->rc_ack_can_sendout_data == 0) && (rack->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) && (TSTMP_LT(us_cts, rack->r_ctl.rc_last_output_to))) { /* * Ok conditions are right for queuing the packets * but we do have to check the flags in the inp, it * could be, if a sack is present, we want to be awoken and * so should process the packets. */ slot_remaining = rack->r_ctl.rc_last_output_to - us_cts; if (rack->rc_tp->t_flags2 & TF2_DONT_SACK_QUEUE) { no_output = 1; } else { /* * If there is no options, or just a * timestamp option, we will want to queue * the packets. This is the same that LRO does * and will need to change with accurate ECN. */ uint32_t *ts_ptr; int optlen; optlen = (th->th_off << 2) - sizeof(struct tcphdr); ts_ptr = (uint32_t *)(th + 1); if ((optlen == 0) || ((optlen == TCPOLEN_TSTAMP_APPA) && (*ts_ptr == TCP_LRO_TS_OPTION))) no_output = 1; } if ((no_output == 1) && (slot_remaining < tcp_min_hptsi_time)) { /* * It is unrealistic to think we can pace in less than * the minimum granularity of the pacer (def:250usec). So * if we have less than that time remaining we should go * ahead and allow output to be "early". We will attempt to * make up for it in any pacing time we try to apply on * the outbound packet. */ no_output = 0; } } /* * If there is a RST or FIN lets dump out the bw * with a FIN the connection may go on but we * may not. */ if ((thflags & TH_FIN) || (thflags & TH_RST)) rack_log_pacing_delay_calc(rack, rack->r_ctl.gp_bw, 0, 0, rack_get_gp_est(rack), /* delRate */ rack_get_lt_bw(rack), /* rttProp */ 20, __LINE__, NULL, 0); if (m->m_flags & M_ACKCMP) { panic("Impossible reach m has ackcmp? m:%p tp:%p", m, tp); } cts = tcp_tv_to_usectick(tv); ms_cts = tcp_tv_to_mssectick(tv); nsegs = m->m_pkthdr.lro_nsegs; counter_u64_add(rack_proc_non_comp_ack, 1); #ifdef TCP_ACCOUNTING sched_pin(); if (thflags & TH_ACK) ts_val = get_cyclecount(); #endif if ((m->m_flags & M_TSTMP) || (m->m_flags & M_TSTMP_LRO)) { mbuf_tstmp2timespec(m, &ts); rack->r_ctl.act_rcv_time.tv_sec = ts.tv_sec; rack->r_ctl.act_rcv_time.tv_usec = ts.tv_nsec/1000; } else rack->r_ctl.act_rcv_time = *tv; kern_prefetch(rack, &prev_state); prev_state = 0; /* * Unscale the window into a 32-bit value. For the SYN_SENT state * the scale is zero. */ tiwin = th->th_win << tp->snd_scale; #ifdef TCP_ACCOUNTING if (thflags & TH_ACK) { /* * We have a tradeoff here. We can either do what we are * doing i.e. pinning to this CPU and then doing the accounting * we could do a critical enter, setup the rdtsc and cpu * as in below, and then validate we are on the same CPU on * exit. I have choosen to not do the critical enter since * that often will gain you a context switch, and instead lock * us (line above this if) to the same CPU with sched_pin(). This * means we may be context switched out for a higher priority * interupt but we won't be moved to another CPU. * * If this occurs (which it won't very often since we most likely * are running this code in interupt context and only a higher * priority will bump us ... clock?) we will falsely add in * to the time the interupt processing time plus the ack processing * time. This is ok since its a rare event. */ ack_val_set = tcp_do_ack_accounting(tp, th, &to, tiwin, ctf_fixed_maxseg(tp)); } #endif /* * Parse options on any incoming segment. */ memset(&to, 0, sizeof(to)); tcp_dooptions(&to, (u_char *)(th + 1), (th->th_off << 2) - sizeof(struct tcphdr), (thflags & TH_SYN) ? TO_SYN : 0); KASSERT(tp->t_state > TCPS_LISTEN, ("%s: TCPS_LISTEN", __func__)); KASSERT(tp->t_state != TCPS_TIME_WAIT, ("%s: TCPS_TIME_WAIT", __func__)); if ((tp->t_state >= TCPS_FIN_WAIT_1) && (tp->t_flags & TF_GPUTINPROG)) { /* * We have a goodput in progress * and we have entered a late state. * Do we have enough data in the sb * to handle the GPUT request? */ uint32_t bytes; bytes = tp->gput_ack - tp->gput_seq; if (SEQ_GT(tp->gput_seq, tp->snd_una)) bytes += tp->gput_seq - tp->snd_una; if (bytes > sbavail(&tptosocket(tp)->so_snd)) { /* * There are not enough bytes in the socket * buffer that have been sent to cover this * measurement. Cancel it. */ rack_log_pacing_delay_calc(rack, (tp->gput_ack - tp->gput_seq) /*flex2*/, rack->r_ctl.rc_gp_srtt /*flex1*/, tp->gput_seq, 0, 0, 18, __LINE__, NULL, 0); tp->t_flags &= ~TF_GPUTINPROG; } } high_seq = th->th_ack; if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval ltv; #ifdef TCP_REQUEST_TRK struct tcp_sendfile_track *tcp_req; if (SEQ_GT(th->th_ack, tp->snd_una)) { tcp_req = tcp_req_find_req_for_seq(tp, (th->th_ack-1)); } else { tcp_req = tcp_req_find_req_for_seq(tp, th->th_ack); } #endif memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.inhpts = tcp_in_hpts(rack->rc_tp); if (rack->rack_no_prr == 0) log.u_bbr.flex1 = rack->r_ctl.rc_prr_sndcnt; else log.u_bbr.flex1 = 0; log.u_bbr.use_lt_bw = rack->r_ent_rec_ns; log.u_bbr.use_lt_bw <<= 1; log.u_bbr.use_lt_bw |= rack->r_might_revert; log.u_bbr.flex2 = rack->r_ctl.rc_num_maps_alloced; log.u_bbr.bbr_state = rack->rc_free_cnt; log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); log.u_bbr.pkts_out = rack->rc_tp->t_maxseg; log.u_bbr.flex3 = m->m_flags; log.u_bbr.flex4 = rack->r_ctl.rc_hpts_flags; log.u_bbr.lost = thflags; log.u_bbr.pacing_gain = 0x1; #ifdef TCP_ACCOUNTING log.u_bbr.cwnd_gain = ack_val_set; #endif log.u_bbr.flex7 = 2; if (m->m_flags & M_TSTMP) { /* Record the hardware timestamp if present */ mbuf_tstmp2timespec(m, &ts); ltv.tv_sec = ts.tv_sec; ltv.tv_usec = ts.tv_nsec / 1000; log.u_bbr.lt_epoch = tcp_tv_to_usectick(<v); } else if (m->m_flags & M_TSTMP_LRO) { /* Record the LRO the arrival timestamp */ mbuf_tstmp2timespec(m, &ts); ltv.tv_sec = ts.tv_sec; ltv.tv_usec = ts.tv_nsec / 1000; log.u_bbr.flex5 = tcp_tv_to_usectick(<v); } log.u_bbr.timeStamp = tcp_get_usecs(<v); /* Log the rcv time */ log.u_bbr.delRate = m->m_pkthdr.rcv_tstmp; #ifdef TCP_REQUEST_TRK log.u_bbr.applimited = tp->t_tcpreq_closed; log.u_bbr.applimited <<= 8; log.u_bbr.applimited |= tp->t_tcpreq_open; log.u_bbr.applimited <<= 8; log.u_bbr.applimited |= tp->t_tcpreq_req; if (tcp_req) { /* Copy out any client req info */ /* seconds */ log.u_bbr.pkt_epoch = (tcp_req->localtime / HPTS_USEC_IN_SEC); /* useconds */ log.u_bbr.delivered = (tcp_req->localtime % HPTS_USEC_IN_SEC); log.u_bbr.rttProp = tcp_req->timestamp; log.u_bbr.cur_del_rate = tcp_req->start; if (tcp_req->flags & TCP_TRK_TRACK_FLG_OPEN) { log.u_bbr.flex8 |= 1; } else { log.u_bbr.flex8 |= 2; log.u_bbr.bw_inuse = tcp_req->end; } log.u_bbr.flex6 = tcp_req->start_seq; if (tcp_req->flags & TCP_TRK_TRACK_FLG_COMP) { log.u_bbr.flex8 |= 4; log.u_bbr.epoch = tcp_req->end_seq; } } #endif TCP_LOG_EVENTP(tp, th, &so->so_rcv, &so->so_snd, TCP_LOG_IN, 0, tlen, &log, true, <v); } /* Remove ack required flag if set, we have one */ if (thflags & TH_ACK) rack->rc_ack_required = 0; if (rack->sack_attack_disable > 0) { rack->r_ctl.ack_during_sd++; rack_log_type_bbrsnd(rack, 0, 0, cts, tv, __LINE__); } if ((thflags & TH_SYN) && (thflags & TH_FIN) && V_drop_synfin) { way_out = 4; retval = 0; m_freem(m); goto done_with_input; } /* * If a segment with the ACK-bit set arrives in the SYN-SENT state * check SEQ.ACK first as described on page 66 of RFC 793, section 3.9. */ if ((tp->t_state == TCPS_SYN_SENT) && (thflags & TH_ACK) && (SEQ_LEQ(th->th_ack, tp->iss) || SEQ_GT(th->th_ack, tp->snd_max))) { tcp_log_end_status(tp, TCP_EI_STATUS_RST_IN_FRONT); ctf_do_dropwithreset(m, tp, th, BANDLIM_RST_OPENPORT, tlen); #ifdef TCP_ACCOUNTING sched_unpin(); #endif return (1); } /* * If timestamps were negotiated during SYN/ACK and a * segment without a timestamp is received, silently drop * the segment, unless it is a RST segment or missing timestamps are * tolerated. * See section 3.2 of RFC 7323. */ if ((tp->t_flags & TF_RCVD_TSTMP) && !(to.to_flags & TOF_TS) && ((thflags & TH_RST) == 0) && (V_tcp_tolerate_missing_ts == 0)) { way_out = 5; retval = 0; m_freem(m); goto done_with_input; } /* * Segment received on connection. Reset idle time and keep-alive * timer. XXX: This should be done after segment validation to * ignore broken/spoofed segs. */ if (tp->t_idle_reduce && (tp->snd_max == tp->snd_una) && (TICKS_2_USEC(ticks - tp->t_rcvtime) >= tp->t_rxtcur)) { counter_u64_add(rack_input_idle_reduces, 1); rack_cc_after_idle(rack, tp); } tp->t_rcvtime = ticks; #ifdef STATS stats_voi_update_abs_ulong(tp->t_stats, VOI_TCP_FRWIN, tiwin); #endif if (tiwin > rack->r_ctl.rc_high_rwnd) rack->r_ctl.rc_high_rwnd = tiwin; /* * TCP ECN processing. XXXJTL: If we ever use ECN, we need to move * this to occur after we've validated the segment. */ if (tcp_ecn_input_segment(tp, thflags, tlen, tcp_packets_this_ack(tp, th->th_ack), iptos)) rack_cong_signal(tp, CC_ECN, th->th_ack, __LINE__); /* * If echoed timestamp is later than the current time, fall back to * non RFC1323 RTT calculation. Normalize timestamp if syncookies * were used when this connection was established. */ if ((to.to_flags & TOF_TS) && (to.to_tsecr != 0)) { to.to_tsecr -= tp->ts_offset; if (TSTMP_GT(to.to_tsecr, ms_cts)) to.to_tsecr = 0; } /* * If its the first time in we need to take care of options and * verify we can do SACK for rack! */ if (rack->r_state == 0) { /* Should be init'd by rack_init() */ KASSERT(rack->rc_inp != NULL, ("%s: rack->rc_inp unexpectedly NULL", __func__)); if (rack->rc_inp == NULL) { rack->rc_inp = inp; } /* * Process options only when we get SYN/ACK back. The SYN * case for incoming connections is handled in tcp_syncache. * According to RFC1323 the window field in a SYN (i.e., a * or ) segment itself is never scaled. XXX * this is traditional behavior, may need to be cleaned up. */ if (tp->t_state == TCPS_SYN_SENT && (thflags & TH_SYN)) { /* Handle parallel SYN for ECN */ tcp_ecn_input_parallel_syn(tp, thflags, iptos); if ((to.to_flags & TOF_SCALE) && (tp->t_flags & TF_REQ_SCALE)) { tp->t_flags |= TF_RCVD_SCALE; tp->snd_scale = to.to_wscale; } else tp->t_flags &= ~TF_REQ_SCALE; /* * Initial send window. It will be updated with the * next incoming segment to the scaled value. */ tp->snd_wnd = th->th_win; rack_validate_fo_sendwin_up(tp, rack); if ((to.to_flags & TOF_TS) && (tp->t_flags & TF_REQ_TSTMP)) { tp->t_flags |= TF_RCVD_TSTMP; tp->ts_recent = to.to_tsval; tp->ts_recent_age = cts; } else tp->t_flags &= ~TF_REQ_TSTMP; if (to.to_flags & TOF_MSS) { tcp_mss(tp, to.to_mss); } if ((tp->t_flags & TF_SACK_PERMIT) && (to.to_flags & TOF_SACKPERM) == 0) tp->t_flags &= ~TF_SACK_PERMIT; if (IS_FASTOPEN(tp->t_flags)) { if (to.to_flags & TOF_FASTOPEN) { uint16_t mss; if (to.to_flags & TOF_MSS) mss = to.to_mss; else if ((inp->inp_vflag & INP_IPV6) != 0) mss = TCP6_MSS; else mss = TCP_MSS; tcp_fastopen_update_cache(tp, mss, to.to_tfo_len, to.to_tfo_cookie); } else tcp_fastopen_disable_path(tp); } } /* * At this point we are at the initial call. Here we decide * if we are doing RACK or not. We do this by seeing if * TF_SACK_PERMIT is set and the sack-not-required is clear. * The code now does do dup-ack counting so if you don't * switch back you won't get rack & TLP, but you will still * get this stack. */ if ((rack_sack_not_required == 0) && ((tp->t_flags & TF_SACK_PERMIT) == 0)) { tcp_switch_back_to_default(tp); (*tp->t_fb->tfb_tcp_do_segment)(tp, m, th, drop_hdrlen, tlen, iptos); #ifdef TCP_ACCOUNTING sched_unpin(); #endif return (1); } tcp_set_hpts(tp); sack_filter_clear(&rack->r_ctl.rack_sf, th->th_ack); } if (thflags & TH_FIN) tcp_log_end_status(tp, TCP_EI_STATUS_CLIENT_FIN); us_cts = tcp_tv_to_usectick(&rack->r_ctl.act_rcv_time); if ((rack->rc_gp_dyn_mul) && (rack->use_fixed_rate == 0) && (rack->rc_always_pace)) { /* Check in on probertt */ rack_check_probe_rtt(rack, us_cts); } rack_clear_rate_sample(rack); if ((rack->forced_ack) && ((tcp_get_flags(th) & TH_RST) == 0)) { rack_handle_probe_response(rack, tiwin, us_cts); } /* * This is the one exception case where we set the rack state * always. All other times (timers etc) we must have a rack-state * set (so we assure we have done the checks above for SACK). */ rack->r_ctl.rc_rcvtime = cts; if (rack->r_state != tp->t_state) rack_set_state(tp, rack); if (SEQ_GT(th->th_ack, tp->snd_una) && (rsm = tqhash_min(rack->r_ctl.tqh)) != NULL) kern_prefetch(rsm, &prev_state); prev_state = rack->r_state; if ((thflags & TH_RST) && ((SEQ_GEQ(th->th_seq, tp->last_ack_sent) && SEQ_LT(th->th_seq, tp->last_ack_sent + tp->rcv_wnd)) || (tp->rcv_wnd == 0 && tp->last_ack_sent == th->th_seq))) { /* The connection will be killed by a reset check the tracepoint */ tcp_trace_point(rack->rc_tp, TCP_TP_RESET_RCV); } retval = (*rack->r_substate) (m, th, so, tp, &to, drop_hdrlen, tlen, tiwin, thflags, nxt_pkt, iptos); if (retval == 0) { /* * If retval is 1 the tcb is unlocked and most likely the tp * is gone. */ INP_WLOCK_ASSERT(inp); if ((rack->rc_gp_dyn_mul) && (rack->rc_always_pace) && (rack->use_fixed_rate == 0) && rack->in_probe_rtt && (rack->r_ctl.rc_time_probertt_starts == 0)) { /* * If we are going for target, lets recheck before * we output. */ rack_check_probe_rtt(rack, us_cts); } if (rack->set_pacing_done_a_iw == 0) { /* How much has been acked? */ if ((tp->snd_una - tp->iss) > (ctf_fixed_maxseg(tp) * 10)) { /* We have enough to set in the pacing segment size */ rack->set_pacing_done_a_iw = 1; rack_set_pace_segments(tp, rack, __LINE__, NULL); } } tcp_rack_xmit_timer_commit(rack, tp); #ifdef TCP_ACCOUNTING /* * If we set the ack_val_se to what ack processing we are doing * we also want to track how many cycles we burned. Note * the bits after tcp_output we let be "free". This is because * we are also tracking the tcp_output times as well. Note the * use of 0xf here since we only have 11 counter (0 - 0xa) and * 0xf cannot be returned and is what we initialize it too to * indicate we are not doing the tabulations. */ if (ack_val_set != 0xf) { uint64_t crtsc; crtsc = get_cyclecount(); if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_proc_time[ack_val_set] += (crtsc - ts_val); } } #endif if ((nxt_pkt == 0) && (no_output == 0)) { if ((rack->r_wanted_output != 0) || (rack->r_fast_output != 0)) { do_output_now: if (tcp_output(tp) < 0) { #ifdef TCP_ACCOUNTING sched_unpin(); #endif return (1); } did_out = 1; } rack_start_hpts_timer(rack, tp, cts, 0, 0, 0); rack_free_trim(rack); } else if ((no_output == 1) && (nxt_pkt == 0) && (tcp_in_hpts(rack->rc_tp) == 0)) { /* * We are not in hpts and we had a pacing timer up. Use * the remaining time (slot_remaining) to restart the timer. */ KASSERT ((slot_remaining != 0), ("slot remaining is zero for rack:%p tp:%p", rack, tp)); rack_start_hpts_timer(rack, tp, cts, slot_remaining, 0, 0); rack_free_trim(rack); } /* Clear the flag, it may have been cleared by output but we may not have */ if ((nxt_pkt == 0) && (tp->t_flags2 & TF2_HPTS_CALLS)) tp->t_flags2 &= ~TF2_HPTS_CALLS; /* Update any rounds needed */ if (rack_verbose_logging && tcp_bblogging_on(rack->rc_tp)) rack_log_hystart_event(rack, high_seq, 8); /* * The draft (v3) calls for us to use SEQ_GEQ, but that * causes issues when we are just going app limited. Lets * instead use SEQ_GT where its equal but more data * is outstanding. * * Also make sure we are on the last ack of a series. We * have to have all the ack's processed in queue to know * if there is something left outstanding. */ if (SEQ_GEQ(tp->snd_una, rack->r_ctl.roundends) && (rack->rc_new_rnd_needed == 0) && (nxt_pkt == 0)) { rack_log_hystart_event(rack, tp->snd_una, 21); rack->r_ctl.current_round++; /* Force the next send to setup the next round */ rack->rc_new_rnd_needed = 1; if (CC_ALGO(tp)->newround != NULL) { CC_ALGO(tp)->newround(&tp->t_ccv, rack->r_ctl.current_round); } } if ((nxt_pkt == 0) && ((rack->r_ctl.rc_hpts_flags & PACE_TMR_MASK) == 0) && (SEQ_GT(tp->snd_max, tp->snd_una) || (tp->t_flags & TF_DELACK) || ((V_tcp_always_keepalive || rack->rc_inp->inp_socket->so_options & SO_KEEPALIVE) && (tp->t_state <= TCPS_CLOSING)))) { /* We could not send (probably in the hpts but stopped the timer earlier)? */ if ((tp->snd_max == tp->snd_una) && ((tp->t_flags & TF_DELACK) == 0) && (tcp_in_hpts(rack->rc_tp)) && (rack->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT)) { /* keep alive not needed if we are hptsi output yet */ ; } else { int late = 0; if (tcp_in_hpts(tp)) { if (rack->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) { us_cts = tcp_get_usecs(NULL); if (TSTMP_GT(rack->r_ctl.rc_last_output_to, us_cts)) { rack->r_early = 1; rack->r_ctl.rc_agg_early += (rack->r_ctl.rc_last_output_to - us_cts); } else late = 1; rack->r_ctl.rc_hpts_flags &= ~PACE_PKT_OUTPUT; } tcp_hpts_remove(tp); } if (late && (did_out == 0)) { /* * We are late in the sending * and we did not call the output * (this probably should not happen). */ goto do_output_now; } rack_start_hpts_timer(rack, tp, tcp_get_usecs(NULL), 0, 0, 0); } way_out = 1; } else if (nxt_pkt == 0) { /* Do we have the correct timer running? */ rack_timer_audit(tp, rack, &so->so_snd); way_out = 2; } done_with_input: rack_log_doseg_done(rack, cts, nxt_pkt, did_out, way_out, max(1, nsegs)); if (did_out) rack->r_wanted_output = 0; } #ifdef TCP_ACCOUNTING sched_unpin(); #endif return (retval); } static void rack_do_segment(struct tcpcb *tp, struct mbuf *m, struct tcphdr *th, int32_t drop_hdrlen, int32_t tlen, uint8_t iptos) { struct timeval tv; /* First lets see if we have old packets */ if (!STAILQ_EMPTY(&tp->t_inqueue)) { if (ctf_do_queued_segments(tp, 1)) { m_freem(m); return; } } if (m->m_flags & M_TSTMP_LRO) { mbuf_tstmp2timeval(m, &tv); } else { /* Should not be should we kassert instead? */ tcp_get_usecs(&tv); } if (rack_do_segment_nounlock(tp, m, th, drop_hdrlen, tlen, iptos, 0, &tv) == 0) { INP_WUNLOCK(tptoinpcb(tp)); } } struct rack_sendmap * tcp_rack_output(struct tcpcb *tp, struct tcp_rack *rack, uint32_t tsused) { struct rack_sendmap *rsm = NULL; int32_t idx; uint32_t srtt = 0, thresh = 0, ts_low = 0; int no_sack = 0; /* Return the next guy to be re-transmitted */ if (tqhash_empty(rack->r_ctl.tqh)) { return (NULL); } if (tp->t_flags & TF_SENTFIN) { /* retran the end FIN? */ return (NULL); } /* ok lets look at this one */ rsm = TAILQ_FIRST(&rack->r_ctl.rc_tmap); if (rack->r_must_retran && rsm && (rsm->r_flags & RACK_MUST_RXT)) { return (rsm); } if (rsm && ((rsm->r_flags & RACK_ACKED) == 0)) { goto check_it; } rsm = rack_find_lowest_rsm(rack); if (rsm == NULL) { return (NULL); } check_it: if (((rack->rc_tp->t_flags & TF_SACK_PERMIT) == 0) || (rack->sack_attack_disable > 0)) { no_sack = 1; } if ((no_sack > 0) && (rsm->r_dupack >= DUP_ACK_THRESHOLD)) { /* * No sack so we automatically do the 3 strikes and * retransmit (no rack timer would be started). */ return (rsm); } if (rsm->r_flags & RACK_ACKED) { return (NULL); } if (((rsm->r_flags & RACK_SACK_PASSED) == 0) && (rsm->r_dupack < DUP_ACK_THRESHOLD)) { /* Its not yet ready */ return (NULL); } srtt = rack_grab_rtt(tp, rack); idx = rsm->r_rtr_cnt - 1; ts_low = (uint32_t)rsm->r_tim_lastsent[idx]; thresh = rack_calc_thresh_rack(rack, srtt, tsused); if ((tsused == ts_low) || (TSTMP_LT(tsused, ts_low))) { /* No time since sending */ return (NULL); } if ((tsused - ts_low) < thresh) { /* It has not been long enough yet */ return (NULL); } if ((rsm->r_dupack >= DUP_ACK_THRESHOLD) || ((rsm->r_flags & RACK_SACK_PASSED) && (rack->sack_attack_disable == 0))) { /* * We have passed the dup-ack threshold * a SACK has indicated this is missing. * Note that if you are a declared attacker * it is only the dup-ack threshold that * will cause retransmits. */ /* log retransmit reason */ rack_log_retran_reason(rack, rsm, (tsused - ts_low), thresh, 1); rack->r_fast_output = 0; return (rsm); } return (NULL); } static void rack_log_pacing_delay_calc(struct tcp_rack *rack, uint32_t len, uint32_t slot, uint64_t bw_est, uint64_t bw, uint64_t len_time, int method, int line, struct rack_sendmap *rsm, uint8_t quality) { if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; if (rack_verbose_logging == 0) { /* * We are not verbose screen out all but * ones we always want. */ if ((method != 2) && (method != 3) && (method != 7) && (method != 14) && (method != 20)) { return; } } memset(&log, 0, sizeof(log)); log.u_bbr.flex1 = slot; log.u_bbr.flex2 = len; log.u_bbr.flex3 = rack->r_ctl.rc_pace_min_segs; log.u_bbr.flex4 = rack->r_ctl.rc_pace_max_segs; log.u_bbr.flex5 = rack->r_ctl.rack_per_of_gp_ss; log.u_bbr.flex6 = rack->r_ctl.rack_per_of_gp_ca; log.u_bbr.use_lt_bw = rack->rc_ack_can_sendout_data; log.u_bbr.use_lt_bw <<= 1; log.u_bbr.use_lt_bw |= rack->r_late; log.u_bbr.use_lt_bw <<= 1; log.u_bbr.use_lt_bw |= rack->r_early; log.u_bbr.use_lt_bw <<= 1; log.u_bbr.use_lt_bw |= rack->app_limited_needs_set; log.u_bbr.use_lt_bw <<= 1; log.u_bbr.use_lt_bw |= rack->rc_gp_filled; log.u_bbr.use_lt_bw <<= 1; log.u_bbr.use_lt_bw |= rack->measure_saw_probe_rtt; log.u_bbr.use_lt_bw <<= 1; log.u_bbr.use_lt_bw |= rack->in_probe_rtt; log.u_bbr.use_lt_bw <<= 1; log.u_bbr.use_lt_bw |= rack->gp_ready; log.u_bbr.pkt_epoch = line; log.u_bbr.epoch = rack->r_ctl.rc_agg_delayed; log.u_bbr.lt_epoch = rack->r_ctl.rc_agg_early; log.u_bbr.applimited = rack->r_ctl.rack_per_of_gp_rec; log.u_bbr.bw_inuse = bw_est; log.u_bbr.delRate = bw; if (rack->r_ctl.gp_bw == 0) log.u_bbr.cur_del_rate = 0; else log.u_bbr.cur_del_rate = rack_get_bw(rack); log.u_bbr.rttProp = len_time; log.u_bbr.pkts_out = rack->r_ctl.rc_rack_min_rtt; log.u_bbr.lost = rack->r_ctl.rc_probertt_sndmax_atexit; log.u_bbr.pacing_gain = rack_get_output_gain(rack, rsm); if (rack->r_ctl.cwnd_to_use < rack->rc_tp->snd_ssthresh) { /* We are in slow start */ log.u_bbr.flex7 = 1; } else { /* we are on congestion avoidance */ log.u_bbr.flex7 = 0; } log.u_bbr.flex8 = method; log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); log.u_bbr.cwnd_gain = rack->rc_gp_saw_rec; log.u_bbr.cwnd_gain <<= 1; log.u_bbr.cwnd_gain |= rack->rc_gp_saw_ss; log.u_bbr.cwnd_gain <<= 1; log.u_bbr.cwnd_gain |= rack->rc_gp_saw_ca; log.u_bbr.bbr_substate = quality; log.u_bbr.bbr_state = rack->dgp_on; log.u_bbr.bbr_state <<= 1; log.u_bbr.bbr_state |= rack->r_fill_less_agg; log.u_bbr.bbr_state <<= 1; log.u_bbr.bbr_state |= rack->rc_pace_to_cwnd; log.u_bbr.bbr_state <<= 2; log.u_bbr.bbr_state |= rack->r_pacing_discount; log.u_bbr.flex7 = ((rack->r_ctl.pacing_discount_amm << 1) | log.u_bbr.flex7); TCP_LOG_EVENTP(rack->rc_tp, NULL, &rack->rc_inp->inp_socket->so_rcv, &rack->rc_inp->inp_socket->so_snd, BBR_LOG_HPTSI_CALC, 0, 0, &log, false, &tv); } } static uint32_t rack_get_pacing_len(struct tcp_rack *rack, uint64_t bw, uint32_t mss) { uint32_t new_tso, user_max, pace_one; user_max = rack->rc_user_set_max_segs * mss; if (rack->rc_force_max_seg) { return (user_max); } if (rack->use_fixed_rate && ((rack->r_ctl.crte == NULL) || (bw != rack->r_ctl.crte->rate))) { /* Use the user mss since we are not exactly matched */ return (user_max); } if (rack_pace_one_seg || (rack->r_ctl.rc_user_set_min_segs == 1)) pace_one = 1; else pace_one = 0; new_tso = tcp_get_pacing_burst_size_w_divisor(rack->rc_tp, bw, mss, pace_one, rack->r_ctl.crte, NULL, rack->r_ctl.pace_len_divisor); if (new_tso > user_max) new_tso = user_max; if (rack->rc_hybrid_mode && rack->r_ctl.client_suggested_maxseg) { if (((uint32_t)rack->r_ctl.client_suggested_maxseg * mss) > new_tso) new_tso = (uint32_t)rack->r_ctl.client_suggested_maxseg * mss; } if (rack->r_ctl.rc_user_set_min_segs && ((rack->r_ctl.rc_user_set_min_segs * mss) > new_tso)) new_tso = rack->r_ctl.rc_user_set_min_segs * mss; return (new_tso); } static uint64_t rack_arrive_at_discounted_rate(struct tcp_rack *rack, uint64_t window_input, uint32_t *rate_set, uint32_t *gain_b) { uint64_t reduced_win; uint32_t gain; if (window_input < rc_init_window(rack)) { /* * The cwnd is collapsed to * nearly zero, maybe because of a time-out? * Lets drop back to the lt-bw. */ reduced_win = rack_get_lt_bw(rack); /* Set the flag so the caller knows its a rate and not a reduced window */ *rate_set = 1; gain = 100; } else if (IN_RECOVERY(rack->rc_tp->t_flags)) { /* * If we are in recover our cwnd needs to be less for * our pacing consideration. */ if (rack->rack_hibeta == 0) { reduced_win = window_input / 2; gain = 50; } else { reduced_win = window_input * rack->r_ctl.saved_hibeta; reduced_win /= 100; gain = rack->r_ctl.saved_hibeta; } } else { /* * Apply Timely factor to increase/decrease the * amount we are pacing at. */ gain = rack_get_output_gain(rack, NULL); if (gain > rack_gain_p5_ub) { gain = rack_gain_p5_ub; } reduced_win = window_input * gain; reduced_win /= 100; } if (gain_b != NULL) *gain_b = gain; /* * What is being returned here is a trimmed down * window values in all cases where rate_set is left * at 0. In one case we actually return the rate (lt_bw). * the "reduced_win" is returned as a slimmed down cwnd that * is then calculated by the caller into a rate when rate_set * is 0. */ return (reduced_win); } static int32_t pace_to_fill_cwnd(struct tcp_rack *rack, int32_t slot, uint32_t len, uint32_t segsiz, int *capped, uint64_t *rate_wanted, uint8_t non_paced) { uint64_t lentim, fill_bw; /* Lets first see if we are full, if so continue with normal rate */ rack->r_via_fill_cw = 0; if (ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked) > rack->r_ctl.cwnd_to_use) return (slot); if ((ctf_outstanding(rack->rc_tp) + (segsiz-1)) > rack->rc_tp->snd_wnd) return (slot); if (rack->r_ctl.rc_last_us_rtt == 0) return (slot); if (rack->rc_pace_fill_if_rttin_range && (rack->r_ctl.rc_last_us_rtt >= (get_filter_value_small(&rack->r_ctl.rc_gp_min_rtt) * rack->rtt_limit_mul))) { /* The rtt is huge, N * smallest, lets not fill */ return (slot); } /* * first lets calculate the b/w based on the last us-rtt * and the the smallest send window. */ fill_bw = min(rack->rc_tp->snd_cwnd, rack->r_ctl.cwnd_to_use); if (rack->rc_fillcw_apply_discount) { uint32_t rate_set = 0; fill_bw = rack_arrive_at_discounted_rate(rack, fill_bw, &rate_set, NULL); if (rate_set) { goto at_lt_bw; } } /* Take the rwnd if its smaller */ if (fill_bw > rack->rc_tp->snd_wnd) fill_bw = rack->rc_tp->snd_wnd; /* Now lets make it into a b/w */ fill_bw *= (uint64_t)HPTS_USEC_IN_SEC; fill_bw /= (uint64_t)rack->r_ctl.rc_last_us_rtt; at_lt_bw: if (rack->r_fill_less_agg) { /* * We want the average of the rate_wanted * and our fill-cw calculated bw. We also want * to cap any increase to be no more than * X times the lt_bw (where X is the rack_bw_multipler). */ uint64_t lt_bw, rate; lt_bw = rack_get_lt_bw(rack); if (lt_bw > *rate_wanted) rate = lt_bw; else rate = *rate_wanted; fill_bw += rate; fill_bw /= 2; if (rack_bw_multipler && (fill_bw > (rate * rack_bw_multipler))) { fill_bw = rate * rack_bw_multipler; } } /* We are below the min b/w */ if (non_paced) *rate_wanted = fill_bw; if ((fill_bw < RACK_MIN_BW) || (fill_bw < *rate_wanted)) return (slot); rack->r_via_fill_cw = 1; if (rack->r_rack_hw_rate_caps && (rack->r_ctl.crte != NULL)) { uint64_t high_rate; high_rate = tcp_hw_highest_rate(rack->r_ctl.crte); if (fill_bw > high_rate) { /* We are capping bw at the highest rate table entry */ if (*rate_wanted > high_rate) { /* The original rate was also capped */ rack->r_via_fill_cw = 0; } rack_log_hdwr_pacing(rack, fill_bw, high_rate, __LINE__, 0, 3); fill_bw = high_rate; if (capped) *capped = 1; } } else if ((rack->r_ctl.crte == NULL) && (rack->rack_hdrw_pacing == 0) && (rack->rack_hdw_pace_ena) && rack->r_rack_hw_rate_caps && (rack->rack_attempt_hdwr_pace == 0) && (rack->rc_inp->inp_route.ro_nh != NULL) && (rack->rc_inp->inp_route.ro_nh->nh_ifp != NULL)) { /* * Ok we may have a first attempt that is greater than our top rate * lets check. */ uint64_t high_rate; high_rate = tcp_hw_highest_rate_ifp(rack->rc_inp->inp_route.ro_nh->nh_ifp, rack->rc_inp); if (high_rate) { if (fill_bw > high_rate) { fill_bw = high_rate; if (capped) *capped = 1; } } } if (rack->r_ctl.bw_rate_cap && (fill_bw > rack->r_ctl.bw_rate_cap)) { if (rack->rc_hybrid_mode) rack_log_hybrid_bw(rack, rack->rc_tp->snd_max, fill_bw, 0, 0, HYBRID_LOG_RATE_CAP, 2, NULL, __LINE__); fill_bw = rack->r_ctl.bw_rate_cap; } /* * Ok fill_bw holds our mythical b/w to fill the cwnd * in an rtt (unless it was capped), what does that * time wise equate too? */ lentim = (uint64_t)(len) * (uint64_t)HPTS_USEC_IN_SEC; lentim /= fill_bw; *rate_wanted = fill_bw; if (non_paced || (lentim < slot)) { rack_log_pacing_delay_calc(rack, len, slot, fill_bw, 0, lentim, 12, __LINE__, NULL, 0); return ((int32_t)lentim); } else return (slot); } static int32_t rack_get_pacing_delay(struct tcp_rack *rack, struct tcpcb *tp, uint32_t len, struct rack_sendmap *rsm, uint32_t segsiz) { uint64_t srtt; int32_t slot = 0; int32_t minslot = 0; int can_start_hw_pacing = 1; int err; int pace_one; if (rack_pace_one_seg || (rack->r_ctl.rc_user_set_min_segs == 1)) pace_one = 1; else pace_one = 0; if (rack->rc_always_pace == 0) { /* * We use the most optimistic possible cwnd/srtt for * sending calculations. This will make our * calculation anticipate getting more through * quicker then possible. But thats ok we don't want * the peer to have a gap in data sending. */ uint64_t cwnd, tr_perms = 0; int32_t reduce = 0; old_method: /* * We keep no precise pacing with the old method * instead we use the pacer to mitigate bursts. */ if (rack->r_ctl.rc_rack_min_rtt) srtt = rack->r_ctl.rc_rack_min_rtt; else srtt = max(tp->t_srtt, 1); if (rack->r_ctl.rc_rack_largest_cwnd) cwnd = rack->r_ctl.rc_rack_largest_cwnd; else cwnd = rack->r_ctl.cwnd_to_use; /* Inflate cwnd by 1000 so srtt of usecs is in ms */ tr_perms = (cwnd * 1000) / srtt; if (tr_perms == 0) { tr_perms = ctf_fixed_maxseg(tp); } /* * Calculate how long this will take to drain, if * the calculation comes out to zero, thats ok we * will use send_a_lot to possibly spin around for * more increasing tot_len_this_send to the point * that its going to require a pace, or we hit the * cwnd. Which in that case we are just waiting for * a ACK. */ slot = len / tr_perms; /* Now do we reduce the time so we don't run dry? */ if (slot && rack_slot_reduction) { reduce = (slot / rack_slot_reduction); if (reduce < slot) { slot -= reduce; } else slot = 0; } slot *= HPTS_USEC_IN_MSEC; if (rack->rc_pace_to_cwnd) { uint64_t rate_wanted = 0; slot = pace_to_fill_cwnd(rack, slot, len, segsiz, NULL, &rate_wanted, 1); rack->rc_ack_can_sendout_data = 1; rack_log_pacing_delay_calc(rack, len, slot, rate_wanted, 0, 0, 14, __LINE__, NULL, 0); } else rack_log_pacing_delay_calc(rack, len, slot, tr_perms, reduce, 0, 7, __LINE__, NULL, 0); /*******************************************************/ /* RRS: We insert non-paced call to stats here for len */ /*******************************************************/ } else { uint64_t bw_est, res, lentim, rate_wanted; uint32_t segs, oh; int capped = 0; int prev_fill; if ((rack->r_rr_config == 1) && rsm) { return (rack->r_ctl.rc_min_to); } if (rack->use_fixed_rate) { rate_wanted = bw_est = rack_get_fixed_pacing_bw(rack); } else if ((rack->r_ctl.init_rate == 0) && (rack->r_ctl.gp_bw == 0)) { /* no way to yet do an estimate */ bw_est = rate_wanted = 0; } else if (rack->dgp_on) { bw_est = rack_get_bw(rack); rate_wanted = rack_get_output_bw(rack, bw_est, rsm, &capped); } else { uint32_t gain, rate_set = 0; rate_wanted = min(rack->rc_tp->snd_cwnd, rack->r_ctl.cwnd_to_use); rate_wanted = rack_arrive_at_discounted_rate(rack, rate_wanted, &rate_set, &gain); if (rate_set == 0) { if (rate_wanted > rack->rc_tp->snd_wnd) rate_wanted = rack->rc_tp->snd_wnd; /* Now lets make it into a b/w */ rate_wanted *= (uint64_t)HPTS_USEC_IN_SEC; rate_wanted /= (uint64_t)rack->r_ctl.rc_last_us_rtt; } bw_est = rate_wanted; rack_log_pacing_delay_calc(rack, rack->rc_tp->snd_cwnd, rack->r_ctl.cwnd_to_use, rate_wanted, bw_est, rack->r_ctl.rc_last_us_rtt, 88, __LINE__, NULL, gain); } if ((bw_est == 0) || (rate_wanted == 0) || ((rack->gp_ready == 0) && (rack->use_fixed_rate == 0))) { /* * No way yet to make a b/w estimate or * our raise is set incorrectly. */ goto old_method; } rack_rate_cap_bw(rack, &rate_wanted, &capped); /* We need to account for all the overheads */ segs = (len + segsiz - 1) / segsiz; /* * We need the diff between 1514 bytes (e-mtu with e-hdr) * and how much data we put in each packet. Yes this * means we may be off if we are larger than 1500 bytes * or smaller. But this just makes us more conservative. */ oh = (tp->t_maxseg - segsiz) + sizeof(struct tcphdr); if (rack->r_is_v6) { #ifdef INET6 oh += sizeof(struct ip6_hdr); #endif } else { #ifdef INET oh += sizeof(struct ip); #endif } /* We add a fixed 14 for the ethernet header */ oh += 14; segs *= oh; lentim = (uint64_t)(len + segs) * (uint64_t)HPTS_USEC_IN_SEC; res = lentim / rate_wanted; slot = (uint32_t)res; if (rack_hw_rate_min && (rate_wanted < rack_hw_rate_min)) { can_start_hw_pacing = 0; if (rack->r_ctl.crte) { /* * Ok we need to release it, we * have fallen too low. */ tcp_rel_pacing_rate(rack->r_ctl.crte, rack->rc_tp); rack->r_ctl.crte = NULL; rack->rack_attempt_hdwr_pace = 0; rack->rack_hdrw_pacing = 0; } } if (rack->r_ctl.crte && (tcp_hw_highest_rate(rack->r_ctl.crte) < rate_wanted)) { /* * We want more than the hardware can give us, * don't start any hw pacing. */ can_start_hw_pacing = 0; if (rack->r_rack_hw_rate_caps == 0) { /* * Ok we need to release it, we * want more than the card can give us and * no rate cap is in place. Set it up so * when we want less we can retry. */ tcp_rel_pacing_rate(rack->r_ctl.crte, rack->rc_tp); rack->r_ctl.crte = NULL; rack->rack_attempt_hdwr_pace = 0; rack->rack_hdrw_pacing = 0; } } if ((rack->r_ctl.crte != NULL) && (rack->rc_inp->inp_snd_tag == NULL)) { /* * We lost our rate somehow, this can happen * if the interface changed underneath us. */ tcp_rel_pacing_rate(rack->r_ctl.crte, rack->rc_tp); rack->r_ctl.crte = NULL; /* Lets re-allow attempting to setup pacing */ rack->rack_hdrw_pacing = 0; rack->rack_attempt_hdwr_pace = 0; rack_log_hdwr_pacing(rack, rate_wanted, bw_est, __LINE__, 0, 6); } prev_fill = rack->r_via_fill_cw; if ((rack->rc_pace_to_cwnd) && (capped == 0) && (rack->dgp_on == 1) && (rack->use_fixed_rate == 0) && (rack->in_probe_rtt == 0) && (IN_FASTRECOVERY(rack->rc_tp->t_flags) == 0)) { /* * We want to pace at our rate *or* faster to * fill the cwnd to the max if its not full. */ slot = pace_to_fill_cwnd(rack, slot, (len+segs), segsiz, &capped, &rate_wanted, 0); /* Re-check to make sure we are not exceeding our max b/w */ if ((rack->r_ctl.crte != NULL) && (tcp_hw_highest_rate(rack->r_ctl.crte) < rate_wanted)) { /* * We want more than the hardware can give us, * don't start any hw pacing. */ can_start_hw_pacing = 0; if (rack->r_rack_hw_rate_caps == 0) { /* * Ok we need to release it, we * want more than the card can give us and * no rate cap is in place. Set it up so * when we want less we can retry. */ tcp_rel_pacing_rate(rack->r_ctl.crte, rack->rc_tp); rack->r_ctl.crte = NULL; rack->rack_attempt_hdwr_pace = 0; rack->rack_hdrw_pacing = 0; rack_set_pace_segments(rack->rc_tp, rack, __LINE__, NULL); } } } if ((rack->rc_inp->inp_route.ro_nh != NULL) && (rack->rc_inp->inp_route.ro_nh->nh_ifp != NULL)) { if ((rack->rack_hdw_pace_ena) && (can_start_hw_pacing > 0) && (rack->rack_hdrw_pacing == 0) && (rack->rack_attempt_hdwr_pace == 0)) { /* * Lets attempt to turn on hardware pacing * if we can. */ rack->rack_attempt_hdwr_pace = 1; rack->r_ctl.crte = tcp_set_pacing_rate(rack->rc_tp, rack->rc_inp->inp_route.ro_nh->nh_ifp, rate_wanted, RS_PACING_GEQ, &err, &rack->r_ctl.crte_prev_rate); if (rack->r_ctl.crte) { rack->rack_hdrw_pacing = 1; rack->r_ctl.rc_pace_max_segs = tcp_get_pacing_burst_size_w_divisor(tp, rate_wanted, segsiz, pace_one, rack->r_ctl.crte, NULL, rack->r_ctl.pace_len_divisor); rack_log_hdwr_pacing(rack, rate_wanted, rack->r_ctl.crte->rate, __LINE__, err, 0); rack->r_ctl.last_hw_bw_req = rate_wanted; } else { counter_u64_add(rack_hw_pace_init_fail, 1); } } else if (rack->rack_hdrw_pacing && (rack->r_ctl.last_hw_bw_req != rate_wanted)) { /* Do we need to adjust our rate? */ const struct tcp_hwrate_limit_table *nrte; if (rack->r_up_only && (rate_wanted < rack->r_ctl.crte->rate)) { /** * We have four possible states here * having to do with the previous time * and this time. * previous | this-time * A) 0 | 0 -- fill_cw not in the picture * B) 1 | 0 -- we were doing a fill-cw but now are not * C) 1 | 1 -- all rates from fill_cw * D) 0 | 1 -- we were doing non-fill and now we are filling * * For case A, C and D we don't allow a drop. But for * case B where we now our on our steady rate we do * allow a drop. * */ if (!((prev_fill == 1) && (rack->r_via_fill_cw == 0))) goto done_w_hdwr; } if ((rate_wanted > rack->r_ctl.crte->rate) || (rate_wanted <= rack->r_ctl.crte_prev_rate)) { if (rack_hw_rate_to_low && (bw_est < rack_hw_rate_to_low)) { /* * The pacing rate is too low for hardware, but * do allow hardware pacing to be restarted. */ rack_log_hdwr_pacing(rack, bw_est, rack->r_ctl.crte->rate, __LINE__, 0, 5); tcp_rel_pacing_rate(rack->r_ctl.crte, rack->rc_tp); rack->r_ctl.crte = NULL; rack->rack_attempt_hdwr_pace = 0; rack->rack_hdrw_pacing = 0; rack_set_pace_segments(rack->rc_tp, rack, __LINE__, &rate_wanted); goto done_w_hdwr; } nrte = tcp_chg_pacing_rate(rack->r_ctl.crte, rack->rc_tp, rack->rc_inp->inp_route.ro_nh->nh_ifp, rate_wanted, RS_PACING_GEQ, &err, &rack->r_ctl.crte_prev_rate); if (nrte == NULL) { /* * Lost the rate, lets drop hardware pacing * period. */ rack->rack_hdrw_pacing = 0; rack->r_ctl.crte = NULL; rack_log_hdwr_pacing(rack, rate_wanted, 0, __LINE__, err, 1); rack_set_pace_segments(rack->rc_tp, rack, __LINE__, &rate_wanted); counter_u64_add(rack_hw_pace_lost, 1); } else if (nrte != rack->r_ctl.crte) { rack->r_ctl.crte = nrte; rack->r_ctl.rc_pace_max_segs = tcp_get_pacing_burst_size_w_divisor(tp, rate_wanted, segsiz, pace_one, rack->r_ctl.crte, NULL, rack->r_ctl.pace_len_divisor); rack_log_hdwr_pacing(rack, rate_wanted, rack->r_ctl.crte->rate, __LINE__, err, 2); rack->r_ctl.last_hw_bw_req = rate_wanted; } } else { /* We just need to adjust the segment size */ rack_set_pace_segments(rack->rc_tp, rack, __LINE__, &rate_wanted); rack_log_hdwr_pacing(rack, rate_wanted, rack->r_ctl.crte->rate, __LINE__, 0, 4); rack->r_ctl.last_hw_bw_req = rate_wanted; } } } if (minslot && (minslot > slot)) { rack_log_pacing_delay_calc(rack, minslot, slot, rack->r_ctl.crte->rate, bw_est, lentim, 98, __LINE__, NULL, 0); slot = minslot; } done_w_hdwr: if (rack_limit_time_with_srtt && (rack->use_fixed_rate == 0) && (rack->rack_hdrw_pacing == 0)) { /* * Sanity check, we do not allow the pacing delay * to be longer than the SRTT of the path. If it is * a slow path, then adding a packet should increase * the RTT and compensate for this i.e. the srtt will * be greater so the allowed pacing time will be greater. * * Note this restriction is not for where a peak rate * is set, we are doing fixed pacing or hardware pacing. */ if (rack->rc_tp->t_srtt) srtt = rack->rc_tp->t_srtt; else srtt = RACK_INITIAL_RTO * HPTS_USEC_IN_MSEC; /* its in ms convert */ if (srtt < (uint64_t)slot) { rack_log_pacing_delay_calc(rack, srtt, slot, rate_wanted, bw_est, lentim, 99, __LINE__, NULL, 0); slot = srtt; } } /*******************************************************************/ /* RRS: We insert paced call to stats here for len and rate_wanted */ /*******************************************************************/ rack_log_pacing_delay_calc(rack, len, slot, rate_wanted, bw_est, lentim, 2, __LINE__, rsm, 0); } if (rack->r_ctl.crte && (rack->r_ctl.crte->rs_num_enobufs > 0)) { /* * If this rate is seeing enobufs when it * goes to send then either the nic is out * of gas or we are mis-estimating the time * somehow and not letting the queue empty * completely. Lets add to the pacing time. */ int hw_boost_delay; hw_boost_delay = rack->r_ctl.crte->time_between * rack_enobuf_hw_boost_mult; if (hw_boost_delay > rack_enobuf_hw_max) hw_boost_delay = rack_enobuf_hw_max; else if (hw_boost_delay < rack_enobuf_hw_min) hw_boost_delay = rack_enobuf_hw_min; slot += hw_boost_delay; } return (slot); } static void rack_start_gp_measurement(struct tcpcb *tp, struct tcp_rack *rack, tcp_seq startseq, uint32_t sb_offset) { struct rack_sendmap *my_rsm = NULL; if (tp->t_state < TCPS_ESTABLISHED) { /* * We don't start any measurements if we are * not at least established. */ return; } if (tp->t_state >= TCPS_FIN_WAIT_1) { /* * We will get no more data into the SB * this means we need to have the data available * before we start a measurement. */ if (sbavail(&tptosocket(tp)->so_snd) < max(rc_init_window(rack), (MIN_GP_WIN * ctf_fixed_maxseg(tp)))) { /* Nope not enough data */ return; } } tp->t_flags |= TF_GPUTINPROG; rack->r_ctl.rc_gp_cumack_ts = 0; rack->r_ctl.rc_gp_lowrtt = 0xffffffff; rack->r_ctl.rc_gp_high_rwnd = rack->rc_tp->snd_wnd; tp->gput_seq = startseq; rack->app_limited_needs_set = 0; if (rack->in_probe_rtt) rack->measure_saw_probe_rtt = 1; else if ((rack->measure_saw_probe_rtt) && (SEQ_GEQ(tp->gput_seq, rack->r_ctl.rc_probertt_sndmax_atexit))) rack->measure_saw_probe_rtt = 0; if (rack->rc_gp_filled) tp->gput_ts = rack->r_ctl.last_cumack_advance; else { /* Special case initial measurement */ struct timeval tv; tp->gput_ts = tcp_get_usecs(&tv); rack->r_ctl.rc_gp_output_ts = rack_to_usec_ts(&tv); } /* * We take a guess out into the future, * if we have no measurement and no * initial rate, we measure the first * initial-windows worth of data to * speed up getting some GP measurement and * thus start pacing. */ if ((rack->rc_gp_filled == 0) && (rack->r_ctl.init_rate == 0)) { rack->app_limited_needs_set = 1; tp->gput_ack = startseq + max(rc_init_window(rack), (MIN_GP_WIN * ctf_fixed_maxseg(tp))); rack_log_pacing_delay_calc(rack, tp->gput_seq, tp->gput_ack, 0, tp->gput_ts, (((uint64_t)rack->r_ctl.rc_app_limited_cnt << 32) | (uint64_t)rack->r_ctl.rc_gp_output_ts), 9, __LINE__, NULL, 0); rack_tend_gp_marks(tp, rack); rack_log_gpset(rack, tp->gput_ack, 0, 0, __LINE__, 1, NULL); return; } if (sb_offset) { /* * We are out somewhere in the sb * can we use the already outstanding data? */ if (rack->r_ctl.rc_app_limited_cnt == 0) { /* * Yes first one is good and in this case * the tp->gput_ts is correctly set based on * the last ack that arrived (no need to * set things up when an ack comes in). */ my_rsm = tqhash_min(rack->r_ctl.tqh); if ((my_rsm == NULL) || (my_rsm->r_rtr_cnt != 1)) { /* retransmission? */ goto use_latest; } } else { if (rack->r_ctl.rc_first_appl == NULL) { /* * If rc_first_appl is NULL * then the cnt should be 0. * This is probably an error, maybe * a KASSERT would be approprate. */ goto use_latest; } /* * If we have a marker pointer to the last one that is * app limited we can use that, but we need to set * things up so that when it gets ack'ed we record * the ack time (if its not already acked). */ rack->app_limited_needs_set = 1; /* * We want to get to the rsm that is either * next with space i.e. over 1 MSS or the one * after that (after the app-limited). */ my_rsm = tqhash_next(rack->r_ctl.tqh, rack->r_ctl.rc_first_appl); if (my_rsm) { if ((my_rsm->r_end - my_rsm->r_start) <= ctf_fixed_maxseg(tp)) /* Have to use the next one */ my_rsm = tqhash_next(rack->r_ctl.tqh, my_rsm); else { /* Use after the first MSS of it is acked */ tp->gput_seq = my_rsm->r_start + ctf_fixed_maxseg(tp); goto start_set; } } if ((my_rsm == NULL) || (my_rsm->r_rtr_cnt != 1)) { /* * Either its a retransmit or * the last is the app-limited one. */ goto use_latest; } } tp->gput_seq = my_rsm->r_start; start_set: if (my_rsm->r_flags & RACK_ACKED) { /* * This one has been acked use the arrival ack time */ struct rack_sendmap *nrsm; tp->gput_ts = (uint32_t)my_rsm->r_ack_arrival; rack->app_limited_needs_set = 0; /* * Ok in this path we need to use the r_end now * since this guy is the starting ack. */ tp->gput_seq = my_rsm->r_end; /* * We also need to adjust up the sendtime * to the send of the next data after my_rsm. */ nrsm = tqhash_next(rack->r_ctl.tqh, my_rsm); if (nrsm != NULL) my_rsm = nrsm; else { /* * The next as not been sent, thats the * case for using the latest. */ goto use_latest; } } rack->r_ctl.rc_gp_output_ts = my_rsm->r_tim_lastsent[0]; tp->gput_ack = tp->gput_seq + rack_get_measure_window(tp, rack); rack->r_ctl.rc_gp_cumack_ts = 0; rack_log_pacing_delay_calc(rack, tp->gput_seq, tp->gput_ack, (uint64_t)my_rsm, tp->gput_ts, (((uint64_t)rack->r_ctl.rc_app_limited_cnt << 32) | (uint64_t)rack->r_ctl.rc_gp_output_ts), 9, __LINE__, my_rsm, 0); /* Now lets make sure all are marked as they should be */ rack_tend_gp_marks(tp, rack); rack_log_gpset(rack, tp->gput_ack, 0, 0, __LINE__, 1, NULL); return; } use_latest: /* * We don't know how long we may have been * idle or if this is the first-send. Lets * setup the flag so we will trim off * the first ack'd data so we get a true * measurement. */ rack->app_limited_needs_set = 1; tp->gput_ack = startseq + rack_get_measure_window(tp, rack); rack->r_ctl.rc_gp_cumack_ts = 0; /* Find this guy so we can pull the send time */ my_rsm = tqhash_find(rack->r_ctl.tqh, startseq); if (my_rsm) { rack->r_ctl.rc_gp_output_ts = my_rsm->r_tim_lastsent[0]; if (my_rsm->r_flags & RACK_ACKED) { /* * Unlikely since its probably what was * just transmitted (but I am paranoid). */ tp->gput_ts = (uint32_t)my_rsm->r_ack_arrival; rack->app_limited_needs_set = 0; } if (SEQ_LT(my_rsm->r_start, tp->gput_seq)) { /* This also is unlikely */ tp->gput_seq = my_rsm->r_start; } } else { /* * TSNH unless we have some send-map limit, * and even at that it should not be hitting * that limit (we should have stopped sending). */ struct timeval tv; microuptime(&tv); rack->r_ctl.rc_gp_output_ts = rack_to_usec_ts(&tv); } rack_tend_gp_marks(tp, rack); rack_log_pacing_delay_calc(rack, tp->gput_seq, tp->gput_ack, (uint64_t)my_rsm, tp->gput_ts, (((uint64_t)rack->r_ctl.rc_app_limited_cnt << 32) | (uint64_t)rack->r_ctl.rc_gp_output_ts), 9, __LINE__, NULL, 0); rack_log_gpset(rack, tp->gput_ack, 0, 0, __LINE__, 1, NULL); } static inline uint32_t rack_what_can_we_send(struct tcpcb *tp, struct tcp_rack *rack, uint32_t cwnd_to_use, uint32_t avail, int32_t sb_offset) { uint32_t len; uint32_t sendwin; if (tp->snd_wnd > cwnd_to_use) sendwin = cwnd_to_use; else sendwin = tp->snd_wnd; if (ctf_outstanding(tp) >= tp->snd_wnd) { /* We never want to go over our peers rcv-window */ len = 0; } else { uint32_t flight; flight = ctf_flight_size(tp, rack->r_ctl.rc_sacked); if (flight >= sendwin) { /* * We have in flight what we are allowed by cwnd (if * it was rwnd blocking it would have hit above out * >= tp->snd_wnd). */ return (0); } len = sendwin - flight; if ((len + ctf_outstanding(tp)) > tp->snd_wnd) { /* We would send too much (beyond the rwnd) */ len = tp->snd_wnd - ctf_outstanding(tp); } if ((len + sb_offset) > avail) { /* * We don't have that much in the SB, how much is * there? */ len = avail - sb_offset; } } return (len); } static void rack_log_fsb(struct tcp_rack *rack, struct tcpcb *tp, struct socket *so, uint32_t flags, unsigned ipoptlen, int32_t orig_len, int32_t len, int error, int rsm_is_null, int optlen, int line, uint16_t mode) { if (rack_verbose_logging && tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.inhpts = tcp_in_hpts(rack->rc_tp); log.u_bbr.flex1 = error; log.u_bbr.flex2 = flags; log.u_bbr.flex3 = rsm_is_null; log.u_bbr.flex4 = ipoptlen; log.u_bbr.flex5 = tp->rcv_numsacks; log.u_bbr.flex6 = rack->r_ctl.rc_agg_early; log.u_bbr.flex7 = optlen; log.u_bbr.flex8 = rack->r_fsb_inited; log.u_bbr.applimited = rack->r_fast_output; log.u_bbr.bw_inuse = rack_get_bw(rack); log.u_bbr.pacing_gain = rack_get_output_gain(rack, NULL); log.u_bbr.cwnd_gain = mode; log.u_bbr.pkts_out = orig_len; log.u_bbr.lt_epoch = len; log.u_bbr.delivered = line; log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); tcp_log_event(tp, NULL, &so->so_rcv, &so->so_snd, TCP_LOG_FSB, 0, len, &log, false, NULL, __func__, __LINE__, &tv); } } static struct mbuf * rack_fo_base_copym(struct mbuf *the_m, uint32_t the_off, int32_t *plen, struct rack_fast_send_blk *fsb, int32_t seglimit, int32_t segsize, int hw_tls) { #ifdef KERN_TLS struct ktls_session *tls, *ntls; #ifdef INVARIANTS struct mbuf *start; #endif #endif struct mbuf *m, *n, **np, *smb; struct mbuf *top; int32_t off, soff; int32_t len = *plen; int32_t fragsize; int32_t len_cp = 0; uint32_t mlen, frags; soff = off = the_off; smb = m = the_m; np = ⊤ top = NULL; #ifdef KERN_TLS if (hw_tls && (m->m_flags & M_EXTPG)) tls = m->m_epg_tls; else tls = NULL; #ifdef INVARIANTS start = m; #endif #endif while (len > 0) { if (m == NULL) { *plen = len_cp; break; } #ifdef KERN_TLS if (hw_tls) { if (m->m_flags & M_EXTPG) ntls = m->m_epg_tls; else ntls = NULL; /* * Avoid mixing TLS records with handshake * data or TLS records from different * sessions. */ if (tls != ntls) { MPASS(m != start); *plen = len_cp; break; } } #endif mlen = min(len, m->m_len - off); if (seglimit) { /* * For M_EXTPG mbufs, add 3 segments * + 1 in case we are crossing page boundaries * + 2 in case the TLS hdr/trailer are used * It is cheaper to just add the segments * than it is to take the cache miss to look * at the mbuf ext_pgs state in detail. */ if (m->m_flags & M_EXTPG) { fragsize = min(segsize, PAGE_SIZE); frags = 3; } else { fragsize = segsize; frags = 0; } /* Break if we really can't fit anymore. */ if ((frags + 1) >= seglimit) { *plen = len_cp; break; } /* * Reduce size if you can't copy the whole * mbuf. If we can't copy the whole mbuf, also * adjust len so the loop will end after this * mbuf. */ if ((frags + howmany(mlen, fragsize)) >= seglimit) { mlen = (seglimit - frags - 1) * fragsize; len = mlen; *plen = len_cp + len; } frags += howmany(mlen, fragsize); if (frags == 0) frags++; seglimit -= frags; KASSERT(seglimit > 0, ("%s: seglimit went too low", __func__)); } n = m_get(M_NOWAIT, m->m_type); *np = n; if (n == NULL) goto nospace; n->m_len = mlen; soff += mlen; len_cp += n->m_len; if (m->m_flags & (M_EXT|M_EXTPG)) { n->m_data = m->m_data + off; mb_dupcl(n, m); } else { bcopy(mtod(m, caddr_t)+off, mtod(n, caddr_t), (u_int)n->m_len); } len -= n->m_len; off = 0; m = m->m_next; np = &n->m_next; if (len || (soff == smb->m_len)) { /* * We have more so we move forward or * we have consumed the entire mbuf and * len has fell to 0. */ soff = 0; smb = m; } } if (fsb != NULL) { fsb->m = smb; fsb->off = soff; if (smb) { /* * Save off the size of the mbuf. We do * this so that we can recognize when it * has been trimmed by sbcut() as acks * come in. */ fsb->o_m_len = smb->m_len; fsb->o_t_len = M_TRAILINGROOM(smb); } else { /* * This is the case where the next mbuf went to NULL. This * means with this copy we have sent everything in the sb. * In theory we could clear the fast_output flag, but lets * not since its possible that we could get more added * and acks that call the extend function which would let * us send more. */ fsb->o_m_len = 0; fsb->o_t_len = 0; } } return (top); nospace: if (top) m_freem(top); return (NULL); } /* * This is a copy of m_copym(), taking the TSO segment size/limit * constraints into account, and advancing the sndptr as it goes. */ static struct mbuf * rack_fo_m_copym(struct tcp_rack *rack, int32_t *plen, int32_t seglimit, int32_t segsize, struct mbuf **s_mb, int *s_soff) { struct mbuf *m, *n; int32_t soff; m = rack->r_ctl.fsb.m; if (M_TRAILINGROOM(m) != rack->r_ctl.fsb.o_t_len) { /* * The trailing space changed, mbufs can grow * at the tail but they can't shrink from * it, KASSERT that. Adjust the orig_m_len to * compensate for this change. */ KASSERT((rack->r_ctl.fsb.o_t_len > M_TRAILINGROOM(m)), ("mbuf:%p rack:%p trailing_space:%jd ots:%u oml:%u mlen:%u\n", m, rack, (intmax_t)M_TRAILINGROOM(m), rack->r_ctl.fsb.o_t_len, rack->r_ctl.fsb.o_m_len, m->m_len)); rack->r_ctl.fsb.o_m_len += (rack->r_ctl.fsb.o_t_len - M_TRAILINGROOM(m)); rack->r_ctl.fsb.o_t_len = M_TRAILINGROOM(m); } if (m->m_len < rack->r_ctl.fsb.o_m_len) { /* * Mbuf shrank, trimmed off the top by an ack, our * offset changes. */ KASSERT((rack->r_ctl.fsb.off >= (rack->r_ctl.fsb.o_m_len - m->m_len)), ("mbuf:%p len:%u rack:%p oml:%u soff:%u\n", m, m->m_len, rack, rack->r_ctl.fsb.o_m_len, rack->r_ctl.fsb.off)); if (rack->r_ctl.fsb.off >= (rack->r_ctl.fsb.o_m_len- m->m_len)) rack->r_ctl.fsb.off -= (rack->r_ctl.fsb.o_m_len - m->m_len); else rack->r_ctl.fsb.off = 0; rack->r_ctl.fsb.o_m_len = m->m_len; #ifdef INVARIANTS } else if (m->m_len > rack->r_ctl.fsb.o_m_len) { panic("rack:%p m:%p m_len grew outside of t_space compensation", rack, m); #endif } soff = rack->r_ctl.fsb.off; KASSERT(soff >= 0, ("%s, negative off %d", __FUNCTION__, soff)); KASSERT(*plen >= 0, ("%s, negative len %d", __FUNCTION__, *plen)); KASSERT(soff < m->m_len, ("%s rack:%p len:%u m:%p m->m_len:%u < off?", __FUNCTION__, rack, *plen, m, m->m_len)); /* Save off the right location before we copy and advance */ *s_soff = soff; *s_mb = rack->r_ctl.fsb.m; n = rack_fo_base_copym(m, soff, plen, &rack->r_ctl.fsb, seglimit, segsize, rack->r_ctl.fsb.hw_tls); return (n); } /* Log the buffer level */ static void rack_log_queue_level(struct tcpcb *tp, struct tcp_rack *rack, int len, struct timeval *tv, uint32_t cts) { uint32_t p_rate = 0, p_queue = 0, err = 0; union tcp_log_stackspecific log; #ifdef RATELIMIT err = in_pcbquery_txrlevel(rack->rc_inp, &p_queue); err = in_pcbquery_txrtlmt(rack->rc_inp, &p_rate); #endif memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.inhpts = tcp_in_hpts(rack->rc_tp); log.u_bbr.flex1 = p_rate; log.u_bbr.flex2 = p_queue; log.u_bbr.flex4 = (uint32_t)rack->r_ctl.crte->using; log.u_bbr.flex5 = (uint32_t)rack->r_ctl.crte->rs_num_enobufs; log.u_bbr.flex6 = rack->r_ctl.crte->time_between; log.u_bbr.flex7 = 99; log.u_bbr.flex8 = 0; log.u_bbr.pkts_out = err; log.u_bbr.delRate = rack->r_ctl.crte->rate; log.u_bbr.timeStamp = cts; log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); tcp_log_event(tp, NULL, NULL, NULL, BBR_LOG_HDWR_PACE, 0, len, &log, false, NULL, __func__, __LINE__, tv); } static uint32_t rack_check_queue_level(struct tcp_rack *rack, struct tcpcb *tp, struct timeval *tv, uint32_t cts, int len, uint32_t segsiz) { uint64_t lentime = 0; #ifdef RATELIMIT uint32_t p_rate = 0, p_queue = 0, err; union tcp_log_stackspecific log; uint64_t bw; err = in_pcbquery_txrlevel(rack->rc_inp, &p_queue); /* Failed or queue is zero */ if (err || (p_queue == 0)) { lentime = 0; goto out; } err = in_pcbquery_txrtlmt(rack->rc_inp, &p_rate); if (err) { lentime = 0; goto out; } /* * If we reach here we have some bytes in * the queue. The number returned is a value * between 0 and 0xffff where ffff is full * and 0 is empty. So how best to make this into * something usable? * * The "safer" way is lets take the b/w gotten * from the query (which should be our b/w rate) * and pretend that a full send (our rc_pace_max_segs) * is outstanding. We factor it so its as if a full * number of our MSS segment is terms of full * ethernet segments are outstanding. */ bw = p_rate / 8; if (bw) { lentime = (rack->r_ctl.rc_pace_max_segs / segsiz); lentime *= ETHERNET_SEGMENT_SIZE; lentime *= (uint64_t)HPTS_USEC_IN_SEC; lentime /= bw; } else { /* TSNH -- KASSERT? */ lentime = 0; } out: if (tcp_bblogging_on(tp)) { memset(&log, 0, sizeof(log)); log.u_bbr.inhpts = tcp_in_hpts(rack->rc_tp); log.u_bbr.flex1 = p_rate; log.u_bbr.flex2 = p_queue; log.u_bbr.flex4 = (uint32_t)rack->r_ctl.crte->using; log.u_bbr.flex5 = (uint32_t)rack->r_ctl.crte->rs_num_enobufs; log.u_bbr.flex6 = rack->r_ctl.crte->time_between; log.u_bbr.flex7 = 99; log.u_bbr.flex8 = 0; log.u_bbr.pkts_out = err; log.u_bbr.delRate = rack->r_ctl.crte->rate; log.u_bbr.cur_del_rate = lentime; log.u_bbr.timeStamp = cts; log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); tcp_log_event(tp, NULL, NULL, NULL, BBR_LOG_HDWR_PACE, 0, len, &log, false, NULL, __func__, __LINE__,tv); } #endif return ((uint32_t)lentime); } static int rack_fast_rsm_output(struct tcpcb *tp, struct tcp_rack *rack, struct rack_sendmap *rsm, uint64_t ts_val, uint32_t cts, uint32_t ms_cts, struct timeval *tv, int len, uint8_t doing_tlp) { /* * Enter the fast retransmit path. We are given that a sched_pin is * in place (if accounting is compliled in) and the cycle count taken * at the entry is in the ts_val. The concept her is that the rsm * now holds the mbuf offsets and such so we can directly transmit * without a lot of overhead, the len field is already set for * us to prohibit us from sending too much (usually its 1MSS). */ struct ip *ip = NULL; struct udphdr *udp = NULL; struct tcphdr *th = NULL; struct mbuf *m = NULL; struct inpcb *inp; uint8_t *cpto; struct tcp_log_buffer *lgb; #ifdef TCP_ACCOUNTING uint64_t crtsc; int cnt_thru = 1; #endif struct tcpopt to; u_char opt[TCP_MAXOLEN]; uint32_t hdrlen, optlen; int32_t slot, segsiz, max_val, tso = 0, error = 0, ulen = 0; uint16_t flags; uint32_t if_hw_tsomaxsegcount = 0, startseq; uint32_t if_hw_tsomaxsegsize; int32_t ip_sendflag = IP_NO_SND_TAG_RL; #ifdef INET6 struct ip6_hdr *ip6 = NULL; if (rack->r_is_v6) { ip6 = (struct ip6_hdr *)rack->r_ctl.fsb.tcp_ip_hdr; hdrlen = sizeof(struct ip6_hdr) + sizeof(struct tcphdr); } else #endif /* INET6 */ { ip = (struct ip *)rack->r_ctl.fsb.tcp_ip_hdr; hdrlen = sizeof(struct tcpiphdr); } if (tp->t_port && (V_tcp_udp_tunneling_port == 0)) { goto failed; } if (doing_tlp) { /* Its a TLP add the flag, it may already be there but be sure */ rsm->r_flags |= RACK_TLP; } else { /* If it was a TLP it is not not on this retransmit */ rsm->r_flags &= ~RACK_TLP; } startseq = rsm->r_start; segsiz = min(ctf_fixed_maxseg(tp), rack->r_ctl.rc_pace_min_segs); inp = rack->rc_inp; to.to_flags = 0; flags = tcp_outflags[tp->t_state]; if (flags & (TH_SYN|TH_RST)) { goto failed; } if (rsm->r_flags & RACK_HAS_FIN) { /* We can't send a FIN here */ goto failed; } if (flags & TH_FIN) { /* We never send a FIN */ flags &= ~TH_FIN; } if (tp->t_flags & TF_RCVD_TSTMP) { to.to_tsval = ms_cts + tp->ts_offset; to.to_tsecr = tp->ts_recent; to.to_flags = TOF_TS; } #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) /* TCP-MD5 (RFC2385). */ if (tp->t_flags & TF_SIGNATURE) to.to_flags |= TOF_SIGNATURE; #endif optlen = tcp_addoptions(&to, opt); hdrlen += optlen; udp = rack->r_ctl.fsb.udp; if (udp) hdrlen += sizeof(struct udphdr); if (rack->r_ctl.rc_pace_max_segs) max_val = rack->r_ctl.rc_pace_max_segs; else if (rack->rc_user_set_max_segs) max_val = rack->rc_user_set_max_segs * segsiz; else max_val = len; if ((tp->t_flags & TF_TSO) && V_tcp_do_tso && (len > segsiz) && (tp->t_port == 0)) tso = 1; #ifdef INET6 if (MHLEN < hdrlen + max_linkhdr) m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); else #endif m = m_gethdr(M_NOWAIT, MT_DATA); if (m == NULL) goto failed; m->m_data += max_linkhdr; m->m_len = hdrlen; th = rack->r_ctl.fsb.th; /* Establish the len to send */ if (len > max_val) len = max_val; if ((tso) && (len + optlen > segsiz)) { uint32_t if_hw_tsomax; int32_t max_len; /* extract TSO information */ if_hw_tsomax = tp->t_tsomax; if_hw_tsomaxsegcount = tp->t_tsomaxsegcount; if_hw_tsomaxsegsize = tp->t_tsomaxsegsize; /* * Check if we should limit by maximum payload * length: */ if (if_hw_tsomax != 0) { /* compute maximum TSO length */ max_len = (if_hw_tsomax - hdrlen - max_linkhdr); if (max_len <= 0) { goto failed; } else if (len > max_len) { len = max_len; } } if (len <= segsiz) { /* * In case there are too many small fragments don't * use TSO: */ tso = 0; } } else { tso = 0; } if ((tso == 0) && (len > segsiz)) len = segsiz; (void)tcp_get_usecs(tv); if ((len == 0) || (len <= MHLEN - hdrlen - max_linkhdr)) { goto failed; } th->th_seq = htonl(rsm->r_start); th->th_ack = htonl(tp->rcv_nxt); /* * The PUSH bit should only be applied * if the full retransmission is made. If * we are sending less than this is the * left hand edge and should not have * the PUSH bit. */ if ((rsm->r_flags & RACK_HAD_PUSH) && (len == (rsm->r_end - rsm->r_start))) flags |= TH_PUSH; th->th_win = htons((u_short)(rack->r_ctl.fsb.recwin >> tp->rcv_scale)); if (th->th_win == 0) { tp->t_sndzerowin++; tp->t_flags |= TF_RXWIN0SENT; } else tp->t_flags &= ~TF_RXWIN0SENT; if (rsm->r_flags & RACK_TLP) { /* * TLP should not count in retran count, but * in its own bin */ counter_u64_add(rack_tlp_retran, 1); counter_u64_add(rack_tlp_retran_bytes, len); } else { tp->t_sndrexmitpack++; KMOD_TCPSTAT_INC(tcps_sndrexmitpack); KMOD_TCPSTAT_ADD(tcps_sndrexmitbyte, len); } #ifdef STATS stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_RETXPB, len); #endif if (rsm->m == NULL) goto failed; if (rsm->m && ((rsm->orig_m_len != rsm->m->m_len) || (M_TRAILINGROOM(rsm->m) != rsm->orig_t_space))) { /* Fix up the orig_m_len and possibly the mbuf offset */ rack_adjust_orig_mlen(rsm); } m->m_next = rack_fo_base_copym(rsm->m, rsm->soff, &len, NULL, if_hw_tsomaxsegcount, if_hw_tsomaxsegsize, rsm->r_hw_tls); if (len <= segsiz) { /* * Must have ran out of mbufs for the copy * shorten it to no longer need tso. Lets * not put on sendalot since we are low on * mbufs. */ tso = 0; } if ((m->m_next == NULL) || (len <= 0)){ goto failed; } if (udp) { if (rack->r_is_v6) ulen = hdrlen + len - sizeof(struct ip6_hdr); else ulen = hdrlen + len - sizeof(struct ip); udp->uh_ulen = htons(ulen); } m->m_pkthdr.rcvif = (struct ifnet *)0; if (TCPS_HAVERCVDSYN(tp->t_state) && (tp->t_flags2 & (TF2_ECN_PERMIT | TF2_ACE_PERMIT))) { int ect = tcp_ecn_output_established(tp, &flags, len, true); if ((tp->t_state == TCPS_SYN_RECEIVED) && (tp->t_flags2 & TF2_ECN_SND_ECE)) tp->t_flags2 &= ~TF2_ECN_SND_ECE; #ifdef INET6 if (rack->r_is_v6) { ip6->ip6_flow &= ~htonl(IPTOS_ECN_MASK << 20); ip6->ip6_flow |= htonl(ect << 20); } else #endif { ip->ip_tos &= ~IPTOS_ECN_MASK; ip->ip_tos |= ect; } } if (rack->r_ctl.crte != NULL) { /* See if we can send via the hw queue */ slot = rack_check_queue_level(rack, tp, tv, cts, len, segsiz); /* If there is nothing in queue (no pacing time) we can send via the hw queue */ if (slot == 0) ip_sendflag = 0; } tcp_set_flags(th, flags); m->m_pkthdr.len = hdrlen + len; /* in6_cksum() need this */ #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) if (to.to_flags & TOF_SIGNATURE) { /* * Calculate MD5 signature and put it into the place * determined before. * NOTE: since TCP options buffer doesn't point into * mbuf's data, calculate offset and use it. */ if (!TCPMD5_ENABLED() || TCPMD5_OUTPUT(m, th, (u_char *)(th + 1) + (to.to_signature - opt)) != 0) { /* * Do not send segment if the calculation of MD5 * digest has failed. */ goto failed; } } #endif #ifdef INET6 if (rack->r_is_v6) { if (tp->t_port) { m->m_pkthdr.csum_flags = CSUM_UDP_IPV6; m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); udp->uh_sum = in6_cksum_pseudo(ip6, ulen, IPPROTO_UDP, 0); th->th_sum = htons(0); UDPSTAT_INC(udps_opackets); } else { m->m_pkthdr.csum_flags = CSUM_TCP_IPV6; m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); th->th_sum = in6_cksum_pseudo(ip6, sizeof(struct tcphdr) + optlen + len, IPPROTO_TCP, 0); } } #endif #if defined(INET6) && defined(INET) else #endif #ifdef INET { if (tp->t_port) { m->m_pkthdr.csum_flags = CSUM_UDP; m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); udp->uh_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, htons(ulen + IPPROTO_UDP)); th->th_sum = htons(0); UDPSTAT_INC(udps_opackets); } else { m->m_pkthdr.csum_flags = CSUM_TCP; m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); th->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, htons(sizeof(struct tcphdr) + IPPROTO_TCP + len + optlen)); } /* IP version must be set here for ipv4/ipv6 checking later */ KASSERT(ip->ip_v == IPVERSION, ("%s: IP version incorrect: %d", __func__, ip->ip_v)); } #endif if (tso) { /* * Here we use segsiz since we have no added options besides * any standard timestamp options (no DSACKs or SACKS are sent * via either fast-path). */ KASSERT(len > segsiz, ("%s: len <= tso_segsz tp:%p", __func__, tp)); m->m_pkthdr.csum_flags |= CSUM_TSO; m->m_pkthdr.tso_segsz = segsiz; } #ifdef INET6 if (rack->r_is_v6) { ip6->ip6_hlim = rack->r_ctl.fsb.hoplimit; ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(*ip6)); if (V_path_mtu_discovery && tp->t_maxseg > V_tcp_minmss) tp->t_flags2 |= TF2_PLPMTU_PMTUD; else tp->t_flags2 &= ~TF2_PLPMTU_PMTUD; } #endif #if defined(INET) && defined(INET6) else #endif #ifdef INET { ip->ip_len = htons(m->m_pkthdr.len); ip->ip_ttl = rack->r_ctl.fsb.hoplimit; if (V_path_mtu_discovery && tp->t_maxseg > V_tcp_minmss) { tp->t_flags2 |= TF2_PLPMTU_PMTUD; if (tp->t_port == 0 || len < V_tcp_minmss) { ip->ip_off |= htons(IP_DF); } } else { tp->t_flags2 &= ~TF2_PLPMTU_PMTUD; } } #endif if (doing_tlp == 0) { /* Set we retransmitted */ rack->rc_gp_saw_rec = 1; } else { /* Its a TLP set ca or ss */ if (tp->snd_cwnd > tp->snd_ssthresh) { /* Set we sent in CA */ rack->rc_gp_saw_ca = 1; } else { /* Set we sent in SS */ rack->rc_gp_saw_ss = 1; } } /* Time to copy in our header */ cpto = mtod(m, uint8_t *); memcpy(cpto, rack->r_ctl.fsb.tcp_ip_hdr, rack->r_ctl.fsb.tcp_ip_hdr_len); th = (struct tcphdr *)(cpto + ((uint8_t *)rack->r_ctl.fsb.th - rack->r_ctl.fsb.tcp_ip_hdr)); if (optlen) { bcopy(opt, th + 1, optlen); th->th_off = (sizeof(struct tcphdr) + optlen) >> 2; } else { th->th_off = sizeof(struct tcphdr) >> 2; } if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; if (rsm->r_flags & RACK_RWND_COLLAPSED) { rack_log_collapse(rack, rsm->r_start, rsm->r_end, 0, __LINE__, 5, rsm->r_flags, rsm); counter_u64_add(rack_collapsed_win_rxt, 1); counter_u64_add(rack_collapsed_win_rxt_bytes, (rsm->r_end - rsm->r_start)); } memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.inhpts = tcp_in_hpts(rack->rc_tp); if (rack->rack_no_prr) log.u_bbr.flex1 = 0; else log.u_bbr.flex1 = rack->r_ctl.rc_prr_sndcnt; log.u_bbr.flex2 = rack->r_ctl.rc_pace_min_segs; log.u_bbr.flex3 = rack->r_ctl.rc_pace_max_segs; log.u_bbr.flex4 = max_val; /* Save off the early/late values */ log.u_bbr.flex6 = rack->r_ctl.rc_agg_early; log.u_bbr.applimited = rack->r_ctl.rc_agg_delayed; log.u_bbr.bw_inuse = rack_get_bw(rack); log.u_bbr.cur_del_rate = rack->r_ctl.gp_bw; if (doing_tlp == 0) log.u_bbr.flex8 = 1; else log.u_bbr.flex8 = 2; log.u_bbr.pacing_gain = rack_get_output_gain(rack, NULL); log.u_bbr.flex7 = 55; log.u_bbr.pkts_out = tp->t_maxseg; log.u_bbr.timeStamp = cts; log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); if (rsm && (rsm->r_rtr_cnt > 0)) { /* * When we have a retransmit we want to log the * burst at send and flight at send from before. */ log.u_bbr.flex5 = rsm->r_fas; log.u_bbr.bbr_substate = rsm->r_bas; } else { /* * This is currently unlikely until we do the * packet pair probes but I will add it for completeness. */ log.u_bbr.flex5 = log.u_bbr.inflight; log.u_bbr.bbr_substate = (uint8_t)((len + segsiz - 1)/segsiz); } log.u_bbr.lt_epoch = rack->r_ctl.cwnd_to_use; log.u_bbr.delivered = 0; log.u_bbr.rttProp = (uint64_t)rsm; log.u_bbr.delRate = rsm->r_flags; log.u_bbr.delRate <<= 31; log.u_bbr.delRate |= rack->r_must_retran; log.u_bbr.delRate <<= 1; log.u_bbr.delRate |= 1; log.u_bbr.pkt_epoch = __LINE__; lgb = tcp_log_event(tp, th, NULL, NULL, TCP_LOG_OUT, ERRNO_UNK, len, &log, false, NULL, __func__, __LINE__, tv); } else lgb = NULL; if ((rack->r_ctl.crte != NULL) && tcp_bblogging_on(tp)) { rack_log_queue_level(tp, rack, len, tv, cts); } #ifdef INET6 if (rack->r_is_v6) { error = ip6_output(m, inp->in6p_outputopts, &inp->inp_route6, ip_sendflag, NULL, NULL, inp); } else #endif #ifdef INET { error = ip_output(m, NULL, &inp->inp_route, ip_sendflag, 0, inp); } #endif m = NULL; if (lgb) { lgb->tlb_errno = error; lgb = NULL; } if (error) { goto failed; } else if (rack->rc_hw_nobuf && (ip_sendflag != IP_NO_SND_TAG_RL)) { rack->rc_hw_nobuf = 0; rack->r_ctl.rc_agg_delayed = 0; rack->r_early = 0; rack->r_late = 0; rack->r_ctl.rc_agg_early = 0; } rack_log_output(tp, &to, len, rsm->r_start, flags, error, rack_to_usec_ts(tv), rsm, RACK_SENT_FP, rsm->m, rsm->soff, rsm->r_hw_tls, segsiz); if (doing_tlp) { rack->rc_tlp_in_progress = 1; rack->r_ctl.rc_tlp_cnt_out++; } if (error == 0) { counter_u64_add(rack_total_bytes, len); tcp_account_for_send(tp, len, 1, doing_tlp, rsm->r_hw_tls); if (doing_tlp) { rack->rc_last_sent_tlp_past_cumack = 0; rack->rc_last_sent_tlp_seq_valid = 1; rack->r_ctl.last_sent_tlp_seq = rsm->r_start; rack->r_ctl.last_sent_tlp_len = rsm->r_end - rsm->r_start; } if (rack->r_ctl.rc_prr_sndcnt >= len) rack->r_ctl.rc_prr_sndcnt -= len; else rack->r_ctl.rc_prr_sndcnt = 0; } tp->t_flags &= ~(TF_ACKNOW | TF_DELACK); rack->forced_ack = 0; /* If we send something zap the FA flag */ if (IN_FASTRECOVERY(tp->t_flags) && rsm) rack->r_ctl.retran_during_recovery += len; { int idx; idx = (len / segsiz) + 3; if (idx >= TCP_MSS_ACCT_ATIMER) counter_u64_add(rack_out_size[(TCP_MSS_ACCT_ATIMER-1)], 1); else counter_u64_add(rack_out_size[idx], 1); } if (tp->t_rtttime == 0) { tp->t_rtttime = ticks; tp->t_rtseq = startseq; KMOD_TCPSTAT_INC(tcps_segstimed); } counter_u64_add(rack_fto_rsm_send, 1); if (error && (error == ENOBUFS)) { if (rack->r_ctl.crte != NULL) { tcp_trace_point(rack->rc_tp, TCP_TP_HWENOBUF); if (tcp_bblogging_on(rack->rc_tp)) rack_log_queue_level(tp, rack, len, tv, cts); } else tcp_trace_point(rack->rc_tp, TCP_TP_ENOBUF); slot = ((1 + rack->rc_enobuf) * HPTS_USEC_IN_MSEC); if (rack->rc_enobuf < 0x7f) rack->rc_enobuf++; if (slot < (10 * HPTS_USEC_IN_MSEC)) slot = 10 * HPTS_USEC_IN_MSEC; if (rack->r_ctl.crte != NULL) { counter_u64_add(rack_saw_enobuf_hw, 1); tcp_rl_log_enobuf(rack->r_ctl.crte); } counter_u64_add(rack_saw_enobuf, 1); } else slot = rack_get_pacing_delay(rack, tp, len, NULL, segsiz); if ((slot == 0) || (rack->rc_always_pace == 0) || (rack->r_rr_config == 1)) { /* * We have no pacing set or we * are using old-style rack or * we are overridden to use the old 1ms pacing. */ slot = rack->r_ctl.rc_min_to; } rack_start_hpts_timer(rack, tp, cts, slot, len, 0); #ifdef TCP_ACCOUNTING crtsc = get_cyclecount(); if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[SND_OUT_DATA] += cnt_thru; } if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_proc_time[SND_OUT_DATA] += (crtsc - ts_val); } if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[CNT_OF_MSS_OUT] += ((len + segsiz - 1) / segsiz); } sched_unpin(); #endif return (0); failed: if (m) m_free(m); return (-1); } static void rack_sndbuf_autoscale(struct tcp_rack *rack) { /* * Automatic sizing of send socket buffer. Often the send buffer * size is not optimally adjusted to the actual network conditions * at hand (delay bandwidth product). Setting the buffer size too * small limits throughput on links with high bandwidth and high * delay (eg. trans-continental/oceanic links). Setting the * buffer size too big consumes too much real kernel memory, * especially with many connections on busy servers. * * The criteria to step up the send buffer one notch are: * 1. receive window of remote host is larger than send buffer * (with a fudge factor of 5/4th); * 2. send buffer is filled to 7/8th with data (so we actually * have data to make use of it); * 3. send buffer fill has not hit maximal automatic size; * 4. our send window (slow start and cogestion controlled) is * larger than sent but unacknowledged data in send buffer. * * Note that the rack version moves things much faster since * we want to avoid hitting cache lines in the rack_fast_output() * path so this is called much less often and thus moves * the SB forward by a percentage. */ struct socket *so; struct tcpcb *tp; uint32_t sendwin, scaleup; tp = rack->rc_tp; so = rack->rc_inp->inp_socket; sendwin = min(rack->r_ctl.cwnd_to_use, tp->snd_wnd); if (V_tcp_do_autosndbuf && so->so_snd.sb_flags & SB_AUTOSIZE) { if ((tp->snd_wnd / 4 * 5) >= so->so_snd.sb_hiwat && sbused(&so->so_snd) >= (so->so_snd.sb_hiwat / 8 * 7) && sbused(&so->so_snd) < V_tcp_autosndbuf_max && sendwin >= (sbused(&so->so_snd) - (tp->snd_nxt - tp->snd_una))) { if (rack_autosndbuf_inc) scaleup = (rack_autosndbuf_inc * so->so_snd.sb_hiwat) / 100; else scaleup = V_tcp_autosndbuf_inc; if (scaleup < V_tcp_autosndbuf_inc) scaleup = V_tcp_autosndbuf_inc; scaleup += so->so_snd.sb_hiwat; if (scaleup > V_tcp_autosndbuf_max) scaleup = V_tcp_autosndbuf_max; if (!sbreserve_locked(so, SO_SND, scaleup, curthread)) so->so_snd.sb_flags &= ~SB_AUTOSIZE; } } } static int rack_fast_output(struct tcpcb *tp, struct tcp_rack *rack, uint64_t ts_val, uint32_t cts, uint32_t ms_cts, struct timeval *tv, long tot_len, int *send_err) { /* * Enter to do fast output. We are given that the sched_pin is * in place (if accounting is compiled in) and the cycle count taken * at entry is in place in ts_val. The idea here is that * we know how many more bytes needs to be sent (presumably either * during pacing or to fill the cwnd and that was greater than * the max-burst). We have how much to send and all the info we * need to just send. */ #ifdef INET struct ip *ip = NULL; #endif struct udphdr *udp = NULL; struct tcphdr *th = NULL; struct mbuf *m, *s_mb; struct inpcb *inp; uint8_t *cpto; struct tcp_log_buffer *lgb; #ifdef TCP_ACCOUNTING uint64_t crtsc; #endif struct tcpopt to; u_char opt[TCP_MAXOLEN]; uint32_t hdrlen, optlen; #ifdef TCP_ACCOUNTING int cnt_thru = 1; #endif int32_t slot, segsiz, len, max_val, tso = 0, sb_offset, error, ulen = 0; uint16_t flags; uint32_t s_soff; uint32_t if_hw_tsomaxsegcount = 0, startseq; uint32_t if_hw_tsomaxsegsize; uint16_t add_flag = RACK_SENT_FP; #ifdef INET6 struct ip6_hdr *ip6 = NULL; if (rack->r_is_v6) { ip6 = (struct ip6_hdr *)rack->r_ctl.fsb.tcp_ip_hdr; hdrlen = sizeof(struct ip6_hdr) + sizeof(struct tcphdr); } else #endif /* INET6 */ { #ifdef INET ip = (struct ip *)rack->r_ctl.fsb.tcp_ip_hdr; hdrlen = sizeof(struct tcpiphdr); #endif } if (tp->t_port && (V_tcp_udp_tunneling_port == 0)) { m = NULL; goto failed; } rack->r_ctl.cwnd_to_use = tp->snd_cwnd; startseq = tp->snd_max; segsiz = min(ctf_fixed_maxseg(tp), rack->r_ctl.rc_pace_min_segs); inp = rack->rc_inp; len = rack->r_ctl.fsb.left_to_send; to.to_flags = 0; flags = rack->r_ctl.fsb.tcp_flags; if (tp->t_flags & TF_RCVD_TSTMP) { to.to_tsval = ms_cts + tp->ts_offset; to.to_tsecr = tp->ts_recent; to.to_flags = TOF_TS; } #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) /* TCP-MD5 (RFC2385). */ if (tp->t_flags & TF_SIGNATURE) to.to_flags |= TOF_SIGNATURE; #endif optlen = tcp_addoptions(&to, opt); hdrlen += optlen; udp = rack->r_ctl.fsb.udp; if (udp) hdrlen += sizeof(struct udphdr); if (rack->r_ctl.rc_pace_max_segs) max_val = rack->r_ctl.rc_pace_max_segs; else if (rack->rc_user_set_max_segs) max_val = rack->rc_user_set_max_segs * segsiz; else max_val = len; if ((tp->t_flags & TF_TSO) && V_tcp_do_tso && (len > segsiz) && (tp->t_port == 0)) tso = 1; again: #ifdef INET6 if (MHLEN < hdrlen + max_linkhdr) m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); else #endif m = m_gethdr(M_NOWAIT, MT_DATA); if (m == NULL) goto failed; m->m_data += max_linkhdr; m->m_len = hdrlen; th = rack->r_ctl.fsb.th; /* Establish the len to send */ if (len > max_val) len = max_val; if ((tso) && (len + optlen > segsiz)) { uint32_t if_hw_tsomax; int32_t max_len; /* extract TSO information */ if_hw_tsomax = tp->t_tsomax; if_hw_tsomaxsegcount = tp->t_tsomaxsegcount; if_hw_tsomaxsegsize = tp->t_tsomaxsegsize; /* * Check if we should limit by maximum payload * length: */ if (if_hw_tsomax != 0) { /* compute maximum TSO length */ max_len = (if_hw_tsomax - hdrlen - max_linkhdr); if (max_len <= 0) { goto failed; } else if (len > max_len) { len = max_len; } } if (len <= segsiz) { /* * In case there are too many small fragments don't * use TSO: */ tso = 0; } } else { tso = 0; } if ((tso == 0) && (len > segsiz)) len = segsiz; (void)tcp_get_usecs(tv); if ((len == 0) || (len <= MHLEN - hdrlen - max_linkhdr)) { goto failed; } sb_offset = tp->snd_max - tp->snd_una; th->th_seq = htonl(tp->snd_max); th->th_ack = htonl(tp->rcv_nxt); th->th_win = htons((u_short)(rack->r_ctl.fsb.recwin >> tp->rcv_scale)); if (th->th_win == 0) { tp->t_sndzerowin++; tp->t_flags |= TF_RXWIN0SENT; } else tp->t_flags &= ~TF_RXWIN0SENT; tp->snd_up = tp->snd_una; /* drag it along, its deprecated */ KMOD_TCPSTAT_INC(tcps_sndpack); KMOD_TCPSTAT_ADD(tcps_sndbyte, len); #ifdef STATS stats_voi_update_abs_u64(tp->t_stats, VOI_TCP_TXPB, len); #endif if (rack->r_ctl.fsb.m == NULL) goto failed; /* s_mb and s_soff are saved for rack_log_output */ m->m_next = rack_fo_m_copym(rack, &len, if_hw_tsomaxsegcount, if_hw_tsomaxsegsize, &s_mb, &s_soff); if (len <= segsiz) { /* * Must have ran out of mbufs for the copy * shorten it to no longer need tso. Lets * not put on sendalot since we are low on * mbufs. */ tso = 0; } if (rack->r_ctl.fsb.rfo_apply_push && (len == rack->r_ctl.fsb.left_to_send)) { tcp_set_flags(th, flags | TH_PUSH); add_flag |= RACK_HAD_PUSH; } if ((m->m_next == NULL) || (len <= 0)){ goto failed; } if (udp) { if (rack->r_is_v6) ulen = hdrlen + len - sizeof(struct ip6_hdr); else ulen = hdrlen + len - sizeof(struct ip); udp->uh_ulen = htons(ulen); } m->m_pkthdr.rcvif = (struct ifnet *)0; if (TCPS_HAVERCVDSYN(tp->t_state) && (tp->t_flags2 & (TF2_ECN_PERMIT | TF2_ACE_PERMIT))) { int ect = tcp_ecn_output_established(tp, &flags, len, false); if ((tp->t_state == TCPS_SYN_RECEIVED) && (tp->t_flags2 & TF2_ECN_SND_ECE)) tp->t_flags2 &= ~TF2_ECN_SND_ECE; #ifdef INET6 if (rack->r_is_v6) { ip6->ip6_flow &= ~htonl(IPTOS_ECN_MASK << 20); ip6->ip6_flow |= htonl(ect << 20); } else #endif { #ifdef INET ip->ip_tos &= ~IPTOS_ECN_MASK; ip->ip_tos |= ect; #endif } } tcp_set_flags(th, flags); m->m_pkthdr.len = hdrlen + len; /* in6_cksum() need this */ #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) if (to.to_flags & TOF_SIGNATURE) { /* * Calculate MD5 signature and put it into the place * determined before. * NOTE: since TCP options buffer doesn't point into * mbuf's data, calculate offset and use it. */ if (!TCPMD5_ENABLED() || TCPMD5_OUTPUT(m, th, (u_char *)(th + 1) + (to.to_signature - opt)) != 0) { /* * Do not send segment if the calculation of MD5 * digest has failed. */ goto failed; } } #endif #ifdef INET6 if (rack->r_is_v6) { if (tp->t_port) { m->m_pkthdr.csum_flags = CSUM_UDP_IPV6; m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); udp->uh_sum = in6_cksum_pseudo(ip6, ulen, IPPROTO_UDP, 0); th->th_sum = htons(0); UDPSTAT_INC(udps_opackets); } else { m->m_pkthdr.csum_flags = CSUM_TCP_IPV6; m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); th->th_sum = in6_cksum_pseudo(ip6, sizeof(struct tcphdr) + optlen + len, IPPROTO_TCP, 0); } } #endif #if defined(INET6) && defined(INET) else #endif #ifdef INET { if (tp->t_port) { m->m_pkthdr.csum_flags = CSUM_UDP; m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); udp->uh_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, htons(ulen + IPPROTO_UDP)); th->th_sum = htons(0); UDPSTAT_INC(udps_opackets); } else { m->m_pkthdr.csum_flags = CSUM_TCP; m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); th->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, htons(sizeof(struct tcphdr) + IPPROTO_TCP + len + optlen)); } /* IP version must be set here for ipv4/ipv6 checking later */ KASSERT(ip->ip_v == IPVERSION, ("%s: IP version incorrect: %d", __func__, ip->ip_v)); } #endif if (tso) { /* * Here we use segsiz since we have no added options besides * any standard timestamp options (no DSACKs or SACKS are sent * via either fast-path). */ KASSERT(len > segsiz, ("%s: len <= tso_segsz tp:%p", __func__, tp)); m->m_pkthdr.csum_flags |= CSUM_TSO; m->m_pkthdr.tso_segsz = segsiz; } #ifdef INET6 if (rack->r_is_v6) { ip6->ip6_hlim = rack->r_ctl.fsb.hoplimit; ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(*ip6)); if (V_path_mtu_discovery && tp->t_maxseg > V_tcp_minmss) tp->t_flags2 |= TF2_PLPMTU_PMTUD; else tp->t_flags2 &= ~TF2_PLPMTU_PMTUD; } #endif #if defined(INET) && defined(INET6) else #endif #ifdef INET { ip->ip_len = htons(m->m_pkthdr.len); ip->ip_ttl = rack->r_ctl.fsb.hoplimit; if (V_path_mtu_discovery && tp->t_maxseg > V_tcp_minmss) { tp->t_flags2 |= TF2_PLPMTU_PMTUD; if (tp->t_port == 0 || len < V_tcp_minmss) { ip->ip_off |= htons(IP_DF); } } else { tp->t_flags2 &= ~TF2_PLPMTU_PMTUD; } } #endif if (tp->snd_cwnd > tp->snd_ssthresh) { /* Set we sent in CA */ rack->rc_gp_saw_ca = 1; } else { /* Set we sent in SS */ rack->rc_gp_saw_ss = 1; } /* Time to copy in our header */ cpto = mtod(m, uint8_t *); memcpy(cpto, rack->r_ctl.fsb.tcp_ip_hdr, rack->r_ctl.fsb.tcp_ip_hdr_len); th = (struct tcphdr *)(cpto + ((uint8_t *)rack->r_ctl.fsb.th - rack->r_ctl.fsb.tcp_ip_hdr)); if (optlen) { bcopy(opt, th + 1, optlen); th->th_off = (sizeof(struct tcphdr) + optlen) >> 2; } else { th->th_off = sizeof(struct tcphdr) >> 2; } if ((rack->r_ctl.crte != NULL) && tcp_bblogging_on(tp)) { rack_log_queue_level(tp, rack, len, tv, cts); } if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.inhpts = tcp_in_hpts(rack->rc_tp); if (rack->rack_no_prr) log.u_bbr.flex1 = 0; else log.u_bbr.flex1 = rack->r_ctl.rc_prr_sndcnt; log.u_bbr.flex2 = rack->r_ctl.rc_pace_min_segs; log.u_bbr.flex3 = rack->r_ctl.rc_pace_max_segs; log.u_bbr.flex4 = max_val; /* Save off the early/late values */ log.u_bbr.flex6 = rack->r_ctl.rc_agg_early; log.u_bbr.applimited = rack->r_ctl.rc_agg_delayed; log.u_bbr.bw_inuse = rack_get_bw(rack); log.u_bbr.cur_del_rate = rack->r_ctl.gp_bw; log.u_bbr.flex8 = 0; log.u_bbr.pacing_gain = rack_get_output_gain(rack, NULL); log.u_bbr.flex7 = 44; log.u_bbr.pkts_out = tp->t_maxseg; log.u_bbr.timeStamp = cts; log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); log.u_bbr.flex5 = log.u_bbr.inflight; log.u_bbr.lt_epoch = rack->r_ctl.cwnd_to_use; log.u_bbr.delivered = 0; log.u_bbr.rttProp = 0; log.u_bbr.delRate = rack->r_must_retran; log.u_bbr.delRate <<= 1; log.u_bbr.pkt_epoch = __LINE__; /* For fast output no retrans so just inflight and how many mss we send */ log.u_bbr.flex5 = log.u_bbr.inflight; log.u_bbr.bbr_substate = (uint8_t)((len + segsiz - 1)/segsiz); lgb = tcp_log_event(tp, th, NULL, NULL, TCP_LOG_OUT, ERRNO_UNK, len, &log, false, NULL, __func__, __LINE__, tv); } else lgb = NULL; #ifdef INET6 if (rack->r_is_v6) { error = ip6_output(m, inp->in6p_outputopts, &inp->inp_route6, 0, NULL, NULL, inp); } #endif #if defined(INET) && defined(INET6) else #endif #ifdef INET { error = ip_output(m, NULL, &inp->inp_route, 0, 0, inp); } #endif if (lgb) { lgb->tlb_errno = error; lgb = NULL; } if (error) { *send_err = error; m = NULL; goto failed; } else if (rack->rc_hw_nobuf) { rack->rc_hw_nobuf = 0; rack->r_ctl.rc_agg_delayed = 0; rack->r_early = 0; rack->r_late = 0; rack->r_ctl.rc_agg_early = 0; } if ((error == 0) && (rack->lt_bw_up == 0)) { /* Unlikely */ rack->r_ctl.lt_timemark = tcp_tv_to_lusectick(tv); rack->r_ctl.lt_seq = tp->snd_una; rack->lt_bw_up = 1; } rack_log_output(tp, &to, len, tp->snd_max, flags, error, rack_to_usec_ts(tv), NULL, add_flag, s_mb, s_soff, rack->r_ctl.fsb.hw_tls, segsiz); m = NULL; if (tp->snd_una == tp->snd_max) { rack->r_ctl.rc_tlp_rxt_last_time = cts; rack_log_progress_event(rack, tp, ticks, PROGRESS_START, __LINE__); tp->t_acktime = ticks; } counter_u64_add(rack_total_bytes, len); tcp_account_for_send(tp, len, 0, 0, rack->r_ctl.fsb.hw_tls); rack->forced_ack = 0; /* If we send something zap the FA flag */ tot_len += len; if ((tp->t_flags & TF_GPUTINPROG) == 0) rack_start_gp_measurement(tp, rack, tp->snd_max, sb_offset); tp->snd_max += len; tp->snd_nxt = tp->snd_max; if (rack->rc_new_rnd_needed) { /* * Update the rnd to start ticking not * that from a time perspective all of * the preceding idle time is "in the round" */ rack->rc_new_rnd_needed = 0; rack->r_ctl.roundends = tp->snd_max; } { int idx; idx = (len / segsiz) + 3; if (idx >= TCP_MSS_ACCT_ATIMER) counter_u64_add(rack_out_size[(TCP_MSS_ACCT_ATIMER-1)], 1); else counter_u64_add(rack_out_size[idx], 1); } if (len <= rack->r_ctl.fsb.left_to_send) rack->r_ctl.fsb.left_to_send -= len; else rack->r_ctl.fsb.left_to_send = 0; if (rack->r_ctl.fsb.left_to_send < segsiz) { rack->r_fast_output = 0; rack->r_ctl.fsb.left_to_send = 0; /* At the end of fast_output scale up the sb */ SOCKBUF_LOCK(&rack->rc_inp->inp_socket->so_snd); rack_sndbuf_autoscale(rack); SOCKBUF_UNLOCK(&rack->rc_inp->inp_socket->so_snd); } if (tp->t_rtttime == 0) { tp->t_rtttime = ticks; tp->t_rtseq = startseq; KMOD_TCPSTAT_INC(tcps_segstimed); } if ((rack->r_ctl.fsb.left_to_send >= segsiz) && (max_val > len) && (tso == 0)) { max_val -= len; len = segsiz; th = rack->r_ctl.fsb.th; #ifdef TCP_ACCOUNTING cnt_thru++; #endif goto again; } tp->t_flags &= ~(TF_ACKNOW | TF_DELACK); counter_u64_add(rack_fto_send, 1); slot = rack_get_pacing_delay(rack, tp, tot_len, NULL, segsiz); rack_start_hpts_timer(rack, tp, cts, slot, tot_len, 0); #ifdef TCP_ACCOUNTING crtsc = get_cyclecount(); if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[SND_OUT_DATA] += cnt_thru; } if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_proc_time[SND_OUT_DATA] += (crtsc - ts_val); } if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[CNT_OF_MSS_OUT] += ((tot_len + segsiz - 1) / segsiz); } sched_unpin(); #endif return (0); failed: if (m) m_free(m); rack->r_fast_output = 0; return (-1); } static inline void rack_setup_fast_output(struct tcpcb *tp, struct tcp_rack *rack, struct sockbuf *sb, int len, int orig_len, int segsiz, uint32_t pace_max_seg, bool hw_tls, uint16_t flags) { rack->r_fast_output = 1; rack->r_ctl.fsb.m = sbsndmbuf(sb, (tp->snd_max - tp->snd_una), &rack->r_ctl.fsb.off); rack->r_ctl.fsb.o_m_len = rack->r_ctl.fsb.m->m_len; rack->r_ctl.fsb.o_t_len = M_TRAILINGROOM(rack->r_ctl.fsb.m); rack->r_ctl.fsb.tcp_flags = flags; rack->r_ctl.fsb.left_to_send = orig_len - len; if (rack->r_ctl.fsb.left_to_send < pace_max_seg) { /* Less than a full sized pace, lets not */ rack->r_fast_output = 0; return; } else { /* Round down to the nearest pace_max_seg */ rack->r_ctl.fsb.left_to_send = rounddown(rack->r_ctl.fsb.left_to_send, pace_max_seg); } if (hw_tls) rack->r_ctl.fsb.hw_tls = 1; else rack->r_ctl.fsb.hw_tls = 0; KASSERT((rack->r_ctl.fsb.left_to_send <= (sbavail(sb) - (tp->snd_max - tp->snd_una))), ("rack:%p left_to_send:%u sbavail:%u out:%u", rack, rack->r_ctl.fsb.left_to_send, sbavail(sb), (tp->snd_max - tp->snd_una))); if (rack->r_ctl.fsb.left_to_send < segsiz) rack->r_fast_output = 0; else { if (rack->r_ctl.fsb.left_to_send == (sbavail(sb) - (tp->snd_max - tp->snd_una))) rack->r_ctl.fsb.rfo_apply_push = 1; else rack->r_ctl.fsb.rfo_apply_push = 0; } } static uint32_t rack_get_hpts_pacing_min_for_bw(struct tcp_rack *rack, int32_t segsiz) { uint64_t min_time; uint32_t maxlen; min_time = (uint64_t)get_hpts_min_sleep_time(); maxlen = (uint32_t)((rack->r_ctl.gp_bw * min_time) / (uint64_t)HPTS_USEC_IN_SEC); maxlen = roundup(maxlen, segsiz); return (maxlen); } static struct rack_sendmap * rack_check_collapsed(struct tcp_rack *rack, uint32_t cts) { struct rack_sendmap *rsm = NULL; int thresh; restart: rsm = tqhash_find(rack->r_ctl.tqh, rack->r_ctl.last_collapse_point); if ((rsm == NULL) || ((rsm->r_flags & RACK_RWND_COLLAPSED) == 0)) { /* Nothing, strange turn off validity */ rack->r_collapse_point_valid = 0; return (NULL); } /* Can we send it yet? */ if (rsm->r_end > (rack->rc_tp->snd_una + rack->rc_tp->snd_wnd)) { /* * Receiver window has not grown enough for * the segment to be put on the wire. */ return (NULL); } if (rsm->r_flags & RACK_ACKED) { /* * It has been sacked, lets move to the * next one if possible. */ rack->r_ctl.last_collapse_point = rsm->r_end; /* Are we done? */ if (SEQ_GEQ(rack->r_ctl.last_collapse_point, rack->r_ctl.high_collapse_point)) { rack->r_collapse_point_valid = 0; return (NULL); } goto restart; } /* Now has it been long enough ? */ thresh = rack_calc_thresh_rack(rack, rack_grab_rtt(rack->rc_tp, rack), cts); if ((cts - ((uint32_t)rsm->r_tim_lastsent[(rsm->r_rtr_cnt-1)])) > thresh) { rack_log_collapse(rack, rsm->r_start, (cts - ((uint32_t)rsm->r_tim_lastsent[(rsm->r_rtr_cnt-1)])), thresh, __LINE__, 6, rsm->r_flags, rsm); return (rsm); } /* Not enough time */ rack_log_collapse(rack, rsm->r_start, (cts - ((uint32_t)rsm->r_tim_lastsent[(rsm->r_rtr_cnt-1)])), thresh, __LINE__, 7, rsm->r_flags, rsm); return (NULL); } static inline void rack_validate_sizes(struct tcp_rack *rack, int32_t *len, int32_t segsiz, uint32_t pace_max_seg) { if ((rack->full_size_rxt == 0) && (rack->shape_rxt_to_pacing_min == 0) && (*len >= segsiz)) { *len = segsiz; } else if (rack->shape_rxt_to_pacing_min && rack->gp_ready) { /* We use pacing min as shaping len req */ uint32_t maxlen; maxlen = rack_get_hpts_pacing_min_for_bw(rack, segsiz); if (*len > maxlen) *len = maxlen; } else { /* * The else is full_size_rxt is on so send it all * note we do need to check this for exceeding * our max segment size due to the fact that * we do sometimes merge chunks together i.e. * we cannot just assume that we will never have * a chunk greater than pace_max_seg */ if (*len > pace_max_seg) *len = pace_max_seg; } } static int rack_output(struct tcpcb *tp) { struct socket *so; uint32_t recwin; uint32_t sb_offset, s_moff = 0; int32_t len, error = 0; uint16_t flags; struct mbuf *m, *s_mb = NULL; struct mbuf *mb; uint32_t if_hw_tsomaxsegcount = 0; uint32_t if_hw_tsomaxsegsize; int32_t segsiz, minseg; long tot_len_this_send = 0; #ifdef INET struct ip *ip = NULL; #endif struct udphdr *udp = NULL; struct tcp_rack *rack; struct tcphdr *th; uint8_t pass = 0; uint8_t mark = 0; uint8_t check_done = 0; uint8_t wanted_cookie = 0; u_char opt[TCP_MAXOLEN]; unsigned ipoptlen, optlen, hdrlen, ulen=0; uint32_t rack_seq; #if defined(IPSEC) || defined(IPSEC_SUPPORT) unsigned ipsec_optlen = 0; #endif int32_t idle, sendalot; int32_t sub_from_prr = 0; volatile int32_t sack_rxmit; struct rack_sendmap *rsm = NULL; int32_t tso, mtu; struct tcpopt to; int32_t slot = 0; int32_t sup_rack = 0; uint32_t cts, ms_cts, delayed, early; uint16_t add_flag = RACK_SENT_SP; /* The doing_tlp flag will be set by the actual rack_timeout_tlp() */ uint8_t doing_tlp = 0; uint32_t cwnd_to_use, pace_max_seg; int32_t do_a_prefetch = 0; int32_t prefetch_rsm = 0; int32_t orig_len = 0; struct timeval tv; int32_t prefetch_so_done = 0; struct tcp_log_buffer *lgb; struct inpcb *inp = tptoinpcb(tp); struct sockbuf *sb; uint64_t ts_val = 0; #ifdef TCP_ACCOUNTING uint64_t crtsc; #endif #ifdef INET6 struct ip6_hdr *ip6 = NULL; int32_t isipv6; #endif bool hpts_calling, hw_tls = false; NET_EPOCH_ASSERT(); INP_WLOCK_ASSERT(inp); /* setup and take the cache hits here */ rack = (struct tcp_rack *)tp->t_fb_ptr; #ifdef TCP_ACCOUNTING sched_pin(); ts_val = get_cyclecount(); #endif hpts_calling = !!(tp->t_flags2 & TF2_HPTS_CALLS); tp->t_flags2 &= ~TF2_HPTS_CALLS; #ifdef TCP_OFFLOAD if (tp->t_flags & TF_TOE) { #ifdef TCP_ACCOUNTING sched_unpin(); #endif return (tcp_offload_output(tp)); } #endif if (rack->rack_deferred_inited == 0) { /* * If we are the connecting socket we will * hit rack_init() when no sequence numbers * are setup. This makes it so we must defer * some initialization. Call that now. */ rack_deferred_init(tp, rack); } /* * For TFO connections in SYN_RECEIVED, only allow the initial * SYN|ACK and those sent by the retransmit timer. */ if (IS_FASTOPEN(tp->t_flags) && (tp->t_state == TCPS_SYN_RECEIVED) && SEQ_GT(tp->snd_max, tp->snd_una) && /* initial SYN|ACK sent */ (rack->r_ctl.rc_resend == NULL)) { /* not a retransmit */ #ifdef TCP_ACCOUNTING sched_unpin(); #endif return (0); } #ifdef INET6 if (rack->r_state) { /* Use the cache line loaded if possible */ isipv6 = rack->r_is_v6; } else { isipv6 = (rack->rc_inp->inp_vflag & INP_IPV6) != 0; } #endif early = 0; cts = tcp_get_usecs(&tv); ms_cts = tcp_tv_to_mssectick(&tv); if (((rack->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) == 0) && tcp_in_hpts(rack->rc_tp)) { /* * We are on the hpts for some timer but not hptsi output. * Remove from the hpts unconditionally. */ rack_timer_cancel(tp, rack, cts, __LINE__); } /* Are we pacing and late? */ if ((rack->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) && TSTMP_GEQ(cts, rack->r_ctl.rc_last_output_to)) { /* We are delayed */ delayed = cts - rack->r_ctl.rc_last_output_to; } else { delayed = 0; } /* Do the timers, which may override the pacer */ if (rack->r_ctl.rc_hpts_flags & PACE_TMR_MASK) { int retval; retval = rack_process_timers(tp, rack, cts, hpts_calling, &doing_tlp); if (retval != 0) { counter_u64_add(rack_out_size[TCP_MSS_ACCT_ATIMER], 1); #ifdef TCP_ACCOUNTING sched_unpin(); #endif /* * If timers want tcp_drop(), then pass error out, * otherwise suppress it. */ return (retval < 0 ? retval : 0); } } if (rack->rc_in_persist) { if (tcp_in_hpts(rack->rc_tp) == 0) { /* Timer is not running */ rack_start_hpts_timer(rack, tp, cts, 0, 0, 0); } #ifdef TCP_ACCOUNTING sched_unpin(); #endif return (0); } if ((rack->rc_ack_required == 1) && (rack->r_timer_override == 0)){ /* A timeout occurred and no ack has arrived */ if (tcp_in_hpts(rack->rc_tp) == 0) { /* Timer is not running */ rack_start_hpts_timer(rack, tp, cts, 0, 0, 0); } #ifdef TCP_ACCOUNTING sched_unpin(); #endif return (0); } if ((rack->r_timer_override) || (rack->rc_ack_can_sendout_data) || (delayed) || (tp->t_state < TCPS_ESTABLISHED)) { rack->rc_ack_can_sendout_data = 0; if (tcp_in_hpts(rack->rc_tp)) tcp_hpts_remove(rack->rc_tp); } else if (tcp_in_hpts(rack->rc_tp)) { /* * On the hpts you can't pass even if ACKNOW is on, we will * when the hpts fires. */ #ifdef TCP_ACCOUNTING crtsc = get_cyclecount(); if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_proc_time[SND_BLOCKED] += (crtsc - ts_val); } if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[SND_BLOCKED]++; } sched_unpin(); #endif counter_u64_add(rack_out_size[TCP_MSS_ACCT_INPACE], 1); return (0); } /* Finish out both pacing early and late accounting */ if ((rack->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) && TSTMP_GT(rack->r_ctl.rc_last_output_to, cts)) { early = rack->r_ctl.rc_last_output_to - cts; } else early = 0; if (delayed) { rack->r_ctl.rc_agg_delayed += delayed; rack->r_late = 1; } else if (early) { rack->r_ctl.rc_agg_early += early; rack->r_early = 1; } /* Now that early/late accounting is done turn off the flag */ rack->r_ctl.rc_hpts_flags &= ~PACE_PKT_OUTPUT; rack->r_wanted_output = 0; rack->r_timer_override = 0; if ((tp->t_state != rack->r_state) && TCPS_HAVEESTABLISHED(tp->t_state)) { rack_set_state(tp, rack); } if ((rack->r_fast_output) && (doing_tlp == 0) && (tp->rcv_numsacks == 0)) { int ret; error = 0; ret = rack_fast_output(tp, rack, ts_val, cts, ms_cts, &tv, tot_len_this_send, &error); if (ret >= 0) return(ret); else if (error) { inp = rack->rc_inp; so = inp->inp_socket; sb = &so->so_snd; goto nomore; } } inp = rack->rc_inp; /* * For TFO connections in SYN_SENT or SYN_RECEIVED, * only allow the initial SYN or SYN|ACK and those sent * by the retransmit timer. */ if (IS_FASTOPEN(tp->t_flags) && ((tp->t_state == TCPS_SYN_RECEIVED) || (tp->t_state == TCPS_SYN_SENT)) && SEQ_GT(tp->snd_max, tp->snd_una) && /* initial SYN or SYN|ACK sent */ (tp->t_rxtshift == 0)) { /* not a retransmit */ cwnd_to_use = rack->r_ctl.cwnd_to_use = tp->snd_cwnd; so = inp->inp_socket; sb = &so->so_snd; goto just_return_nolock; } /* * Determine length of data that should be transmitted, and flags * that will be used. If there is some data or critical controls * (SYN, RST) to send, then transmit; otherwise, investigate * further. */ idle = (tp->t_flags & TF_LASTIDLE) || (tp->snd_max == tp->snd_una); if (tp->t_idle_reduce) { if (idle && (TICKS_2_USEC(ticks - tp->t_rcvtime) >= tp->t_rxtcur)) rack_cc_after_idle(rack, tp); } tp->t_flags &= ~TF_LASTIDLE; if (idle) { if (tp->t_flags & TF_MORETOCOME) { tp->t_flags |= TF_LASTIDLE; idle = 0; } } if ((tp->snd_una == tp->snd_max) && rack->r_ctl.rc_went_idle_time && TSTMP_GT(cts, rack->r_ctl.rc_went_idle_time)) { idle = cts - rack->r_ctl.rc_went_idle_time; if (idle > rack_min_probertt_hold) { /* Count as a probe rtt */ if (rack->in_probe_rtt == 0) { rack->r_ctl.rc_lower_rtt_us_cts = cts; rack->r_ctl.rc_time_probertt_entered = rack->r_ctl.rc_lower_rtt_us_cts; rack->r_ctl.rc_time_probertt_starts = rack->r_ctl.rc_lower_rtt_us_cts; rack->r_ctl.rc_time_of_last_probertt = rack->r_ctl.rc_lower_rtt_us_cts; } else { rack_exit_probertt(rack, cts); } } idle = 0; } if (rack_use_fsb && (rack->r_ctl.fsb.tcp_ip_hdr) && (rack->r_fsb_inited == 0) && (rack->r_state != TCPS_CLOSED)) rack_init_fsb_block(tp, rack, tcp_outflags[tp->t_state]); again: /* * If we've recently taken a timeout, snd_max will be greater than * snd_nxt. There may be SACK information that allows us to avoid * resending already delivered data. Adjust snd_nxt accordingly. */ sendalot = 0; cts = tcp_get_usecs(&tv); ms_cts = tcp_tv_to_mssectick(&tv); tso = 0; mtu = 0; segsiz = min(ctf_fixed_maxseg(tp), rack->r_ctl.rc_pace_min_segs); minseg = segsiz; if (rack->r_ctl.rc_pace_max_segs == 0) pace_max_seg = rack->rc_user_set_max_segs * segsiz; else pace_max_seg = rack->r_ctl.rc_pace_max_segs; sb_offset = tp->snd_max - tp->snd_una; cwnd_to_use = rack->r_ctl.cwnd_to_use = tp->snd_cwnd; flags = tcp_outflags[tp->t_state]; while (rack->rc_free_cnt < rack_free_cache) { rsm = rack_alloc(rack); if (rsm == NULL) { if (hpts_calling) /* Retry in a ms */ slot = (1 * HPTS_USEC_IN_MSEC); so = inp->inp_socket; sb = &so->so_snd; goto just_return_nolock; } TAILQ_INSERT_TAIL(&rack->r_ctl.rc_free, rsm, r_tnext); rack->rc_free_cnt++; rsm = NULL; } sack_rxmit = 0; len = 0; rsm = NULL; if (flags & TH_RST) { SOCKBUF_LOCK(&inp->inp_socket->so_snd); so = inp->inp_socket; sb = &so->so_snd; goto send; } if (rack->r_ctl.rc_resend) { /* Retransmit timer */ rsm = rack->r_ctl.rc_resend; rack->r_ctl.rc_resend = NULL; len = rsm->r_end - rsm->r_start; sack_rxmit = 1; sendalot = 0; KASSERT(SEQ_LEQ(tp->snd_una, rsm->r_start), ("%s:%d: r.start:%u < SND.UNA:%u; tp:%p, rack:%p, rsm:%p", __func__, __LINE__, rsm->r_start, tp->snd_una, tp, rack, rsm)); sb_offset = rsm->r_start - tp->snd_una; rack_validate_sizes(rack, &len, segsiz, pace_max_seg); } else if (rack->r_collapse_point_valid && ((rsm = rack_check_collapsed(rack, cts)) != NULL)) { /* * If an RSM is returned then enough time has passed * for us to retransmit it. Move up the collapse point, * since this rsm has its chance to retransmit now. */ tcp_trace_point(rack->rc_tp, TCP_TP_COLLAPSED_RXT); rack->r_ctl.last_collapse_point = rsm->r_end; /* Are we done? */ if (SEQ_GEQ(rack->r_ctl.last_collapse_point, rack->r_ctl.high_collapse_point)) rack->r_collapse_point_valid = 0; sack_rxmit = 1; /* We are not doing a TLP */ doing_tlp = 0; len = rsm->r_end - rsm->r_start; sb_offset = rsm->r_start - tp->snd_una; sendalot = 0; rack_validate_sizes(rack, &len, segsiz, pace_max_seg); } else if ((rsm = tcp_rack_output(tp, rack, cts)) != NULL) { /* We have a retransmit that takes precedence */ if ((!IN_FASTRECOVERY(tp->t_flags)) && ((rsm->r_flags & RACK_MUST_RXT) == 0) && ((tp->t_flags & TF_WASFRECOVERY) == 0)) { /* Enter recovery if not induced by a time-out */ rack_cong_signal(tp, CC_NDUPACK, tp->snd_una, __LINE__); } #ifdef INVARIANTS if (SEQ_LT(rsm->r_start, tp->snd_una)) { panic("Huh, tp:%p rack:%p rsm:%p start:%u < snd_una:%u\n", tp, rack, rsm, rsm->r_start, tp->snd_una); } #endif len = rsm->r_end - rsm->r_start; KASSERT(SEQ_LEQ(tp->snd_una, rsm->r_start), ("%s:%d: r.start:%u < SND.UNA:%u; tp:%p, rack:%p, rsm:%p", __func__, __LINE__, rsm->r_start, tp->snd_una, tp, rack, rsm)); sb_offset = rsm->r_start - tp->snd_una; sendalot = 0; rack_validate_sizes(rack, &len, segsiz, pace_max_seg); if (len > 0) { sack_rxmit = 1; KMOD_TCPSTAT_INC(tcps_sack_rexmits); KMOD_TCPSTAT_ADD(tcps_sack_rexmit_bytes, min(len, segsiz)); } } else if (rack->r_ctl.rc_tlpsend) { /* Tail loss probe */ long cwin; long tlen; /* * Check if we can do a TLP with a RACK'd packet * this can happen if we are not doing the rack * cheat and we skipped to a TLP and it * went off. */ rsm = rack->r_ctl.rc_tlpsend; /* We are doing a TLP make sure the flag is preent */ rsm->r_flags |= RACK_TLP; rack->r_ctl.rc_tlpsend = NULL; sack_rxmit = 1; tlen = rsm->r_end - rsm->r_start; if (tlen > segsiz) tlen = segsiz; KASSERT(SEQ_LEQ(tp->snd_una, rsm->r_start), ("%s:%d: r.start:%u < SND.UNA:%u; tp:%p, rack:%p, rsm:%p", __func__, __LINE__, rsm->r_start, tp->snd_una, tp, rack, rsm)); sb_offset = rsm->r_start - tp->snd_una; cwin = min(tp->snd_wnd, tlen); len = cwin; } if (rack->r_must_retran && (doing_tlp == 0) && (SEQ_GT(tp->snd_max, tp->snd_una)) && (rsm == NULL)) { /* * There are two different ways that we * can get into this block: * a) This is a non-sack connection, we had a time-out * and thus r_must_retran was set and everything * left outstanding as been marked for retransmit. * b) The MTU of the path shrank, so that everything * was marked to be retransmitted with the smaller * mtu and r_must_retran was set. * * This means that we expect the sendmap (outstanding) * to all be marked must. We can use the tmap to * look at them. * */ int sendwin, flight; sendwin = min(tp->snd_wnd, tp->snd_cwnd); flight = ctf_flight_size(tp, rack->r_ctl.rc_out_at_rto); if (flight >= sendwin) { /* * We can't send yet. */ so = inp->inp_socket; sb = &so->so_snd; goto just_return_nolock; } /* * This is the case a/b mentioned above. All * outstanding/not-acked should be marked. * We can use the tmap to find them. */ rsm = TAILQ_FIRST(&rack->r_ctl.rc_tmap); if (rsm == NULL) { /* TSNH */ rack->r_must_retran = 0; rack->r_ctl.rc_out_at_rto = 0; so = inp->inp_socket; sb = &so->so_snd; goto just_return_nolock; } if ((rsm->r_flags & RACK_MUST_RXT) == 0) { /* * The first one does not have the flag, did we collapse * further up in our list? */ rack->r_must_retran = 0; rack->r_ctl.rc_out_at_rto = 0; rsm = NULL; sack_rxmit = 0; } else { sack_rxmit = 1; len = rsm->r_end - rsm->r_start; sb_offset = rsm->r_start - tp->snd_una; sendalot = 0; if ((rack->full_size_rxt == 0) && (rack->shape_rxt_to_pacing_min == 0) && (len >= segsiz)) len = segsiz; else if (rack->shape_rxt_to_pacing_min && rack->gp_ready) { /* We use pacing min as shaping len req */ uint32_t maxlen; maxlen = rack_get_hpts_pacing_min_for_bw(rack, segsiz); if (len > maxlen) len = maxlen; } /* * Delay removing the flag RACK_MUST_RXT so * that the fastpath for retransmit will * work with this rsm. */ } } /* * Enforce a connection sendmap count limit if set * as long as we are not retransmiting. */ if ((rsm == NULL) && (rack->do_detection == 0) && (V_tcp_map_entries_limit > 0) && (rack->r_ctl.rc_num_maps_alloced >= V_tcp_map_entries_limit)) { counter_u64_add(rack_to_alloc_limited, 1); if (!rack->alloc_limit_reported) { rack->alloc_limit_reported = 1; counter_u64_add(rack_alloc_limited_conns, 1); } so = inp->inp_socket; sb = &so->so_snd; goto just_return_nolock; } if (rsm && (rsm->r_flags & RACK_HAS_FIN)) { /* we are retransmitting the fin */ len--; if (len) { /* * When retransmitting data do *not* include the * FIN. This could happen from a TLP probe. */ flags &= ~TH_FIN; } } if (rsm && rack->r_fsb_inited && rack_use_rsm_rfo && ((rsm->r_flags & RACK_HAS_FIN) == 0)) { int ret; ret = rack_fast_rsm_output(tp, rack, rsm, ts_val, cts, ms_cts, &tv, len, doing_tlp); if (ret == 0) return (0); } so = inp->inp_socket; sb = &so->so_snd; if (do_a_prefetch == 0) { kern_prefetch(sb, &do_a_prefetch); do_a_prefetch = 1; } #ifdef NETFLIX_SHARED_CWND if ((tp->t_flags2 & TF2_TCP_SCWND_ALLOWED) && rack->rack_enable_scwnd) { /* We are doing cwnd sharing */ if (rack->gp_ready && (rack->rack_attempted_scwnd == 0) && (rack->r_ctl.rc_scw == NULL) && tp->t_lib) { /* The pcbid is in, lets make an attempt */ counter_u64_add(rack_try_scwnd, 1); rack->rack_attempted_scwnd = 1; rack->r_ctl.rc_scw = tcp_shared_cwnd_alloc(tp, &rack->r_ctl.rc_scw_index, segsiz); } if (rack->r_ctl.rc_scw && (rack->rack_scwnd_is_idle == 1) && sbavail(&so->so_snd)) { /* we are no longer out of data */ tcp_shared_cwnd_active(rack->r_ctl.rc_scw, rack->r_ctl.rc_scw_index); rack->rack_scwnd_is_idle = 0; } if (rack->r_ctl.rc_scw) { /* First lets update and get the cwnd */ rack->r_ctl.cwnd_to_use = cwnd_to_use = tcp_shared_cwnd_update(rack->r_ctl.rc_scw, rack->r_ctl.rc_scw_index, tp->snd_cwnd, tp->snd_wnd, segsiz); } } #endif /* * Get standard flags, and add SYN or FIN if requested by 'hidden' * state flags. */ if (tp->t_flags & TF_NEEDFIN) flags |= TH_FIN; if (tp->t_flags & TF_NEEDSYN) flags |= TH_SYN; if ((sack_rxmit == 0) && (prefetch_rsm == 0)) { void *end_rsm; end_rsm = TAILQ_LAST_FAST(&rack->r_ctl.rc_tmap, rack_sendmap, r_tnext); if (end_rsm) kern_prefetch(end_rsm, &prefetch_rsm); prefetch_rsm = 1; } SOCKBUF_LOCK(sb); /* * If snd_nxt == snd_max and we have transmitted a FIN, the * sb_offset will be > 0 even if so_snd.sb_cc is 0, resulting in a * negative length. This can also occur when TCP opens up its * congestion window while receiving additional duplicate acks after * fast-retransmit because TCP will reset snd_nxt to snd_max after * the fast-retransmit. * * In the normal retransmit-FIN-only case, however, snd_nxt will be * set to snd_una, the sb_offset will be 0, and the length may wind * up 0. * * If sack_rxmit is true we are retransmitting from the scoreboard * in which case len is already set. */ if ((sack_rxmit == 0) && (TCPS_HAVEESTABLISHED(tp->t_state) || IS_FASTOPEN(tp->t_flags))) { uint32_t avail; avail = sbavail(sb); if (SEQ_GT(tp->snd_nxt, tp->snd_una) && avail) sb_offset = tp->snd_nxt - tp->snd_una; else sb_offset = 0; if ((IN_FASTRECOVERY(tp->t_flags) == 0) || rack->rack_no_prr) { if (rack->r_ctl.rc_tlp_new_data) { /* TLP is forcing out new data */ if (rack->r_ctl.rc_tlp_new_data > (uint32_t) (avail - sb_offset)) { rack->r_ctl.rc_tlp_new_data = (uint32_t) (avail - sb_offset); } if ((rack->r_ctl.rc_tlp_new_data + sb_offset) > tp->snd_wnd) { if (tp->snd_wnd > sb_offset) len = tp->snd_wnd - sb_offset; else len = 0; } else { len = rack->r_ctl.rc_tlp_new_data; } rack->r_ctl.rc_tlp_new_data = 0; } else { len = rack_what_can_we_send(tp, rack, cwnd_to_use, avail, sb_offset); } if ((rack->r_ctl.crte == NULL) && IN_FASTRECOVERY(tp->t_flags) && (rack->full_size_rxt == 0) && (rack->shape_rxt_to_pacing_min == 0) && (len > segsiz)) { /* * For prr=off, we need to send only 1 MSS * at a time. We do this because another sack could * be arriving that causes us to send retransmits and * we don't want to be on a long pace due to a larger send * that keeps us from sending out the retransmit. */ len = segsiz; } else if (rack->shape_rxt_to_pacing_min && rack->gp_ready) { /* We use pacing min as shaping len req */ uint32_t maxlen; maxlen = rack_get_hpts_pacing_min_for_bw(rack, segsiz); if (len > maxlen) len = maxlen; }/* The else is full_size_rxt is on so send it all */ } else { uint32_t outstanding; /* * We are inside of a Fast recovery episode, this * is caused by a SACK or 3 dup acks. At this point * we have sent all the retransmissions and we rely * on PRR to dictate what we will send in the form of * new data. */ outstanding = tp->snd_max - tp->snd_una; if ((rack->r_ctl.rc_prr_sndcnt + outstanding) > tp->snd_wnd) { if (tp->snd_wnd > outstanding) { len = tp->snd_wnd - outstanding; /* Check to see if we have the data */ if ((sb_offset + len) > avail) { /* It does not all fit */ if (avail > sb_offset) len = avail - sb_offset; else len = 0; } } else { len = 0; } } else if (avail > sb_offset) { len = avail - sb_offset; } else { len = 0; } if (len > 0) { if (len > rack->r_ctl.rc_prr_sndcnt) { len = rack->r_ctl.rc_prr_sndcnt; } if (len > 0) { sub_from_prr = 1; } } if (len > segsiz) { /* * We should never send more than a MSS when * retransmitting or sending new data in prr * mode unless the override flag is on. Most * likely the PRR algorithm is not going to * let us send a lot as well :-) */ if (rack->r_ctl.rc_prr_sendalot == 0) { len = segsiz; } } else if (len < segsiz) { /* * Do we send any? The idea here is if the * send empty's the socket buffer we want to * do it. However if not then lets just wait * for our prr_sndcnt to get bigger. */ long leftinsb; leftinsb = sbavail(sb) - sb_offset; if (leftinsb > len) { /* This send does not empty the sb */ len = 0; } } } } else if (!TCPS_HAVEESTABLISHED(tp->t_state)) { /* * If you have not established * and are not doing FAST OPEN * no data please. */ if ((sack_rxmit == 0) && (!IS_FASTOPEN(tp->t_flags))){ len = 0; sb_offset = 0; } } if (prefetch_so_done == 0) { kern_prefetch(so, &prefetch_so_done); prefetch_so_done = 1; } /* * Lop off SYN bit if it has already been sent. However, if this is * SYN-SENT state and if segment contains data and if we don't know * that foreign host supports TAO, suppress sending segment. */ if ((flags & TH_SYN) && SEQ_GT(tp->snd_nxt, tp->snd_una) && ((sack_rxmit == 0) && (tp->t_rxtshift == 0))) { /* * When sending additional segments following a TFO SYN|ACK, * do not include the SYN bit. */ if (IS_FASTOPEN(tp->t_flags) && (tp->t_state == TCPS_SYN_RECEIVED)) flags &= ~TH_SYN; } /* * Be careful not to send data and/or FIN on SYN segments. This * measure is needed to prevent interoperability problems with not * fully conformant TCP implementations. */ if ((flags & TH_SYN) && (tp->t_flags & TF_NOOPT)) { len = 0; flags &= ~TH_FIN; } /* * On TFO sockets, ensure no data is sent in the following cases: * * - When retransmitting SYN|ACK on a passively-created socket * * - When retransmitting SYN on an actively created socket * * - When sending a zero-length cookie (cookie request) on an * actively created socket * * - When the socket is in the CLOSED state (RST is being sent) */ if (IS_FASTOPEN(tp->t_flags) && (((flags & TH_SYN) && (tp->t_rxtshift > 0)) || ((tp->t_state == TCPS_SYN_SENT) && (tp->t_tfo_client_cookie_len == 0)) || (flags & TH_RST))) { sack_rxmit = 0; len = 0; } /* Without fast-open there should never be data sent on a SYN */ if ((flags & TH_SYN) && (!IS_FASTOPEN(tp->t_flags))) { tp->snd_nxt = tp->iss; len = 0; } if ((len > segsiz) && (tcp_dsack_block_exists(tp))) { /* We only send 1 MSS if we have a DSACK block */ add_flag |= RACK_SENT_W_DSACK; len = segsiz; } orig_len = len; if (len <= 0) { /* * If FIN has been sent but not acked, but we haven't been * called to retransmit, len will be < 0. Otherwise, window * shrank after we sent into it. If window shrank to 0, * cancel pending retransmit, pull snd_nxt back to (closed) * window, and set the persist timer if it isn't already * going. If the window didn't close completely, just wait * for an ACK. * * We also do a general check here to ensure that we will * set the persist timer when we have data to send, but a * 0-byte window. This makes sure the persist timer is set * even if the packet hits one of the "goto send" lines * below. */ len = 0; if ((tp->snd_wnd == 0) && (TCPS_HAVEESTABLISHED(tp->t_state)) && (tp->snd_una == tp->snd_max) && (sb_offset < (int)sbavail(sb))) { rack_enter_persist(tp, rack, cts, tp->snd_una); } } else if ((rsm == NULL) && (doing_tlp == 0) && (len < pace_max_seg)) { /* * We are not sending a maximum sized segment for * some reason. Should we not send anything (think * sws or persists)? */ if ((tp->snd_wnd < min((rack->r_ctl.rc_high_rwnd/2), minseg)) && (TCPS_HAVEESTABLISHED(tp->t_state)) && (len < minseg) && (len < (int)(sbavail(sb) - sb_offset))) { /* * Here the rwnd is less than * the minimum pacing size, this is not a retransmit, * we are established and * the send is not the last in the socket buffer * we send nothing, and we may enter persists * if nothing is outstanding. */ len = 0; if (tp->snd_max == tp->snd_una) { /* * Nothing out we can * go into persists. */ rack_enter_persist(tp, rack, cts, tp->snd_una); } } else if ((cwnd_to_use >= max(minseg, (segsiz * 4))) && (ctf_flight_size(tp, rack->r_ctl.rc_sacked) > (2 * segsiz)) && (len < (int)(sbavail(sb) - sb_offset)) && (len < minseg)) { /* * Here we are not retransmitting, and * the cwnd is not so small that we could * not send at least a min size (rxt timer * not having gone off), We have 2 segments or * more already in flight, its not the tail end * of the socket buffer and the cwnd is blocking * us from sending out a minimum pacing segment size. * Lets not send anything. */ len = 0; } else if (((tp->snd_wnd - ctf_outstanding(tp)) < min((rack->r_ctl.rc_high_rwnd/2), minseg)) && (ctf_flight_size(tp, rack->r_ctl.rc_sacked) > (2 * segsiz)) && (len < (int)(sbavail(sb) - sb_offset)) && (TCPS_HAVEESTABLISHED(tp->t_state))) { /* * Here we have a send window but we have * filled it up and we can't send another pacing segment. * We also have in flight more than 2 segments * and we are not completing the sb i.e. we allow * the last bytes of the sb to go out even if * its not a full pacing segment. */ len = 0; } else if ((rack->r_ctl.crte != NULL) && (tp->snd_wnd >= (pace_max_seg * max(1, rack_hw_rwnd_factor))) && (cwnd_to_use >= (pace_max_seg + (4 * segsiz))) && (ctf_flight_size(tp, rack->r_ctl.rc_sacked) >= (2 * segsiz)) && (len < (int)(sbavail(sb) - sb_offset))) { /* * Here we are doing hardware pacing, this is not a TLP, * we are not sending a pace max segment size, there is rwnd * room to send at least N pace_max_seg, the cwnd is greater * than or equal to a full pacing segments plus 4 mss and we have 2 or * more segments in flight and its not the tail of the socket buffer. * * We don't want to send instead we need to get more ack's in to * allow us to send a full pacing segment. Normally, if we are pacing * about the right speed, we should have finished our pacing * send as most of the acks have come back if we are at the * right rate. This is a bit fuzzy since return path delay * can delay the acks, which is why we want to make sure we * have cwnd space to have a bit more than a max pace segments in flight. * * If we have not gotten our acks back we are pacing at too high a * rate delaying will not hurt and will bring our GP estimate down by * injecting the delay. If we don't do this we will send * 2 MSS out in response to the acks being clocked in which * defeats the point of hw-pacing (i.e. to help us get * larger TSO's out). */ len = 0; } } /* len will be >= 0 after this point. */ KASSERT(len >= 0, ("[%s:%d]: len < 0", __func__, __LINE__)); rack_sndbuf_autoscale(rack); /* * Decide if we can use TCP Segmentation Offloading (if supported by * hardware). * * TSO may only be used if we are in a pure bulk sending state. The * presence of TCP-MD5, SACK retransmits, SACK advertizements and IP * options prevent using TSO. With TSO the TCP header is the same * (except for the sequence number) for all generated packets. This * makes it impossible to transmit any options which vary per * generated segment or packet. * * IPv4 handling has a clear separation of ip options and ip header * flags while IPv6 combines both in in6p_outputopts. ip6_optlen() does * the right thing below to provide length of just ip options and thus * checking for ipoptlen is enough to decide if ip options are present. */ ipoptlen = 0; #if defined(IPSEC) || defined(IPSEC_SUPPORT) /* * Pre-calculate here as we save another lookup into the darknesses * of IPsec that way and can actually decide if TSO is ok. */ #ifdef INET6 if (isipv6 && IPSEC_ENABLED(ipv6)) ipsec_optlen = IPSEC_HDRSIZE(ipv6, inp); #ifdef INET else #endif #endif /* INET6 */ #ifdef INET if (IPSEC_ENABLED(ipv4)) ipsec_optlen = IPSEC_HDRSIZE(ipv4, inp); #endif /* INET */ #endif #if defined(IPSEC) || defined(IPSEC_SUPPORT) ipoptlen += ipsec_optlen; #endif if ((tp->t_flags & TF_TSO) && V_tcp_do_tso && len > segsiz && (tp->t_port == 0) && ((tp->t_flags & TF_SIGNATURE) == 0) && tp->rcv_numsacks == 0 && sack_rxmit == 0 && ipoptlen == 0) tso = 1; { uint32_t outstanding __unused; outstanding = tp->snd_max - tp->snd_una; if (tp->t_flags & TF_SENTFIN) { /* * If we sent a fin, snd_max is 1 higher than * snd_una */ outstanding--; } if (sack_rxmit) { if ((rsm->r_flags & RACK_HAS_FIN) == 0) flags &= ~TH_FIN; } else { if (SEQ_LT(tp->snd_nxt + len, tp->snd_una + sbused(sb))) flags &= ~TH_FIN; } } recwin = lmin(lmax(sbspace(&so->so_rcv), 0), (long)TCP_MAXWIN << tp->rcv_scale); /* * Sender silly window avoidance. We transmit under the following * conditions when len is non-zero: * * - We have a full segment (or more with TSO) - This is the last * buffer in a write()/send() and we are either idle or running * NODELAY - we've timed out (e.g. persist timer) - we have more * then 1/2 the maximum send window's worth of data (receiver may be * limited the window size) - we need to retransmit */ if (len) { if (len >= segsiz) { goto send; } /* * NOTE! on localhost connections an 'ack' from the remote * end may occur synchronously with the output and cause us * to flush a buffer queued with moretocome. XXX * */ if (!(tp->t_flags & TF_MORETOCOME) && /* normal case */ (idle || (tp->t_flags & TF_NODELAY)) && ((uint32_t)len + (uint32_t)sb_offset >= sbavail(sb)) && (tp->t_flags & TF_NOPUSH) == 0) { pass = 2; goto send; } if ((tp->snd_una == tp->snd_max) && len) { /* Nothing outstanding */ pass = 22; goto send; } if (len >= tp->max_sndwnd / 2 && tp->max_sndwnd > 0) { pass = 4; goto send; } if (SEQ_LT(tp->snd_nxt, tp->snd_max)) { /* retransmit case */ pass = 5; goto send; } if (sack_rxmit) { pass = 6; goto send; } if (((tp->snd_wnd - ctf_outstanding(tp)) < segsiz) && (ctf_outstanding(tp) < (segsiz * 2))) { /* * We have less than two MSS outstanding (delayed ack) * and our rwnd will not let us send a full sized * MSS. Lets go ahead and let this small segment * out because we want to try to have at least two * packets inflight to not be caught by delayed ack. */ pass = 12; goto send; } } /* * Sending of standalone window updates. * * Window updates are important when we close our window due to a * full socket buffer and are opening it again after the application * reads data from it. Once the window has opened again and the * remote end starts to send again the ACK clock takes over and * provides the most current window information. * * We must avoid the silly window syndrome whereas every read from * the receive buffer, no matter how small, causes a window update * to be sent. We also should avoid sending a flurry of window * updates when the socket buffer had queued a lot of data and the * application is doing small reads. * * Prevent a flurry of pointless window updates by only sending an * update when we can increase the advertized window by more than * 1/4th of the socket buffer capacity. When the buffer is getting * full or is very small be more aggressive and send an update * whenever we can increase by two mss sized segments. In all other * situations the ACK's to new incoming data will carry further * window increases. * * Don't send an independent window update if a delayed ACK is * pending (it will get piggy-backed on it) or the remote side * already has done a half-close and won't send more data. Skip * this if the connection is in T/TCP half-open state. */ if (recwin > 0 && !(tp->t_flags & TF_NEEDSYN) && !(tp->t_flags & TF_DELACK) && !TCPS_HAVERCVDFIN(tp->t_state)) { /* * "adv" is the amount we could increase the window, taking * into account that we are limited by TCP_MAXWIN << * tp->rcv_scale. */ int32_t adv; int oldwin; adv = recwin; if (SEQ_GT(tp->rcv_adv, tp->rcv_nxt)) { oldwin = (tp->rcv_adv - tp->rcv_nxt); if (adv > oldwin) adv -= oldwin; else { /* We can't increase the window */ adv = 0; } } else oldwin = 0; /* * If the new window size ends up being the same as or less * than the old size when it is scaled, then don't force * a window update. */ if (oldwin >> tp->rcv_scale >= (adv + oldwin) >> tp->rcv_scale) goto dontupdate; if (adv >= (int32_t)(2 * segsiz) && (adv >= (int32_t)(so->so_rcv.sb_hiwat / 4) || recwin <= (int32_t)(so->so_rcv.sb_hiwat / 8) || so->so_rcv.sb_hiwat <= 8 * segsiz)) { pass = 7; goto send; } if (2 * adv >= (int32_t) so->so_rcv.sb_hiwat) { pass = 23; goto send; } } dontupdate: /* * Send if we owe the peer an ACK, RST, SYN, or urgent data. ACKNOW * is also a catch-all for the retransmit timer timeout case. */ if (tp->t_flags & TF_ACKNOW) { pass = 8; goto send; } if (((flags & TH_SYN) && (tp->t_flags & TF_NEEDSYN) == 0)) { pass = 9; goto send; } /* * If our state indicates that FIN should be sent and we have not * yet done so, then we need to send. */ if ((flags & TH_FIN) && (tp->snd_nxt == tp->snd_una)) { pass = 11; goto send; } /* * No reason to send a segment, just return. */ just_return: SOCKBUF_UNLOCK(sb); just_return_nolock: { int app_limited = CTF_JR_SENT_DATA; if (tot_len_this_send > 0) { /* Make sure snd_nxt is up to max */ rack->r_ctl.fsb.recwin = recwin; slot = rack_get_pacing_delay(rack, tp, tot_len_this_send, NULL, segsiz); if ((error == 0) && rack_use_rfo && ((flags & (TH_SYN|TH_FIN)) == 0) && (ipoptlen == 0) && (tp->snd_nxt == tp->snd_max) && (tp->rcv_numsacks == 0) && rack->r_fsb_inited && TCPS_HAVEESTABLISHED(tp->t_state) && ((IN_RECOVERY(tp->t_flags)) == 0) && (rack->r_must_retran == 0) && ((tp->t_flags & TF_NEEDFIN) == 0) && (len > 0) && (orig_len > 0) && (orig_len > len) && ((orig_len - len) >= segsiz) && ((optlen == 0) || ((optlen == TCPOLEN_TSTAMP_APPA) && (to.to_flags & TOF_TS)))) { /* We can send at least one more MSS using our fsb */ rack_setup_fast_output(tp, rack, sb, len, orig_len, segsiz, pace_max_seg, hw_tls, flags); } else rack->r_fast_output = 0; rack_log_fsb(rack, tp, so, flags, ipoptlen, orig_len, len, 0, 1, optlen, __LINE__, 1); if (SEQ_GT(tp->snd_max, tp->snd_nxt)) tp->snd_nxt = tp->snd_max; } else { int end_window = 0; uint32_t seq = tp->gput_ack; rsm = tqhash_max(rack->r_ctl.tqh); if (rsm) { /* * Mark the last sent that we just-returned (hinting * that delayed ack may play a role in any rtt measurement). */ rsm->r_just_ret = 1; } counter_u64_add(rack_out_size[TCP_MSS_ACCT_JUSTRET], 1); rack->r_ctl.rc_agg_delayed = 0; rack->r_early = 0; rack->r_late = 0; rack->r_ctl.rc_agg_early = 0; if ((ctf_outstanding(tp) + min(max(segsiz, (rack->r_ctl.rc_high_rwnd/2)), minseg)) >= tp->snd_wnd) { /* We are limited by the rwnd */ app_limited = CTF_JR_RWND_LIMITED; if (IN_FASTRECOVERY(tp->t_flags)) rack->r_ctl.rc_prr_sndcnt = 0; } else if (ctf_outstanding(tp) >= sbavail(sb)) { /* We are limited by whats available -- app limited */ app_limited = CTF_JR_APP_LIMITED; if (IN_FASTRECOVERY(tp->t_flags)) rack->r_ctl.rc_prr_sndcnt = 0; } else if ((idle == 0) && ((tp->t_flags & TF_NODELAY) == 0) && ((uint32_t)len + (uint32_t)sb_offset >= sbavail(sb)) && (len < segsiz)) { /* * No delay is not on and the * user is sending less than 1MSS. This * brings out SWS avoidance so we * don't send. Another app-limited case. */ app_limited = CTF_JR_APP_LIMITED; } else if (tp->t_flags & TF_NOPUSH) { /* * The user has requested no push of * the last segment and we are * at the last segment. Another app * limited case. */ app_limited = CTF_JR_APP_LIMITED; } else if ((ctf_outstanding(tp) + minseg) > cwnd_to_use) { /* Its the cwnd */ app_limited = CTF_JR_CWND_LIMITED; } else if (IN_FASTRECOVERY(tp->t_flags) && (rack->rack_no_prr == 0) && (rack->r_ctl.rc_prr_sndcnt < segsiz)) { app_limited = CTF_JR_PRR; } else { /* Now why here are we not sending? */ #ifdef NOW #ifdef INVARIANTS panic("rack:%p hit JR_ASSESSING case cwnd_to_use:%u?", rack, cwnd_to_use); #endif #endif app_limited = CTF_JR_ASSESSING; } /* * App limited in some fashion, for our pacing GP * measurements we don't want any gap (even cwnd). * Close down the measurement window. */ if (rack_cwnd_block_ends_measure && ((app_limited == CTF_JR_CWND_LIMITED) || (app_limited == CTF_JR_PRR))) { /* * The reason we are not sending is * the cwnd (or prr). We have been configured * to end the measurement window in * this case. */ end_window = 1; } else if (rack_rwnd_block_ends_measure && (app_limited == CTF_JR_RWND_LIMITED)) { /* * We are rwnd limited and have been * configured to end the measurement * window in this case. */ end_window = 1; } else if (app_limited == CTF_JR_APP_LIMITED) { /* * A true application limited period, we have * ran out of data. */ end_window = 1; } else if (app_limited == CTF_JR_ASSESSING) { /* * In the assessing case we hit the end of * the if/else and had no known reason * This will panic us under invariants.. * * If we get this out in logs we need to * investagate which reason we missed. */ end_window = 1; } if (end_window) { uint8_t log = 0; /* Adjust the Gput measurement */ if ((tp->t_flags & TF_GPUTINPROG) && SEQ_GT(tp->gput_ack, tp->snd_max)) { tp->gput_ack = tp->snd_max; if ((tp->gput_ack - tp->gput_seq) < (MIN_GP_WIN * segsiz)) { /* * There is not enough to measure. */ tp->t_flags &= ~TF_GPUTINPROG; rack_log_pacing_delay_calc(rack, (tp->gput_ack - tp->gput_seq) /*flex2*/, rack->r_ctl.rc_gp_srtt /*flex1*/, tp->gput_seq, 0, 0, 18, __LINE__, NULL, 0); } else log = 1; } /* Mark the last packet has app limited */ rsm = tqhash_max(rack->r_ctl.tqh); if (rsm && ((rsm->r_flags & RACK_APP_LIMITED) == 0)) { if (rack->r_ctl.rc_app_limited_cnt == 0) rack->r_ctl.rc_end_appl = rack->r_ctl.rc_first_appl = rsm; else { /* * Go out to the end app limited and mark * this new one as next and move the end_appl up * to this guy. */ if (rack->r_ctl.rc_end_appl) rack->r_ctl.rc_end_appl->r_nseq_appl = rsm->r_start; rack->r_ctl.rc_end_appl = rsm; } rsm->r_flags |= RACK_APP_LIMITED; rack->r_ctl.rc_app_limited_cnt++; } if (log) rack_log_pacing_delay_calc(rack, rack->r_ctl.rc_app_limited_cnt, seq, tp->gput_ack, 0, 0, 4, __LINE__, NULL, 0); } } /* Check if we need to go into persists or not */ if ((tp->snd_max == tp->snd_una) && TCPS_HAVEESTABLISHED(tp->t_state) && sbavail(sb) && (sbavail(sb) > tp->snd_wnd) && (tp->snd_wnd < min((rack->r_ctl.rc_high_rwnd/2), minseg))) { /* Yes lets make sure to move to persist before timer-start */ rack_enter_persist(tp, rack, rack->r_ctl.rc_rcvtime, tp->snd_una); } rack_start_hpts_timer(rack, tp, cts, slot, tot_len_this_send, sup_rack); rack_log_type_just_return(rack, cts, tot_len_this_send, slot, hpts_calling, app_limited, cwnd_to_use); } #ifdef NETFLIX_SHARED_CWND if ((sbavail(sb) == 0) && rack->r_ctl.rc_scw) { tcp_shared_cwnd_idle(rack->r_ctl.rc_scw, rack->r_ctl.rc_scw_index); rack->rack_scwnd_is_idle = 1; } #endif #ifdef TCP_ACCOUNTING if (tot_len_this_send > 0) { crtsc = get_cyclecount(); if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[SND_OUT_DATA]++; } if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_proc_time[SND_OUT_DATA] += (crtsc - ts_val); } if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[CNT_OF_MSS_OUT] += ((tot_len_this_send + segsiz - 1) / segsiz); } } else { crtsc = get_cyclecount(); if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[SND_LIMITED]++; } if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_proc_time[SND_LIMITED] += (crtsc - ts_val); } } sched_unpin(); #endif return (0); send: if ((rack->r_ctl.crte != NULL) && (rsm == NULL) && ((rack->rc_hw_nobuf == 1) || (rack_hw_check_queue && (check_done == 0)))) { /* * We only want to do this once with the hw_check_queue, * for the enobuf case we would only do it once if * we come around to again, the flag will be clear. */ check_done = 1; slot = rack_check_queue_level(rack, tp, &tv, cts, len, segsiz); if (slot) { rack->r_ctl.rc_agg_delayed = 0; rack->r_ctl.rc_agg_early = 0; rack->r_early = 0; rack->r_late = 0; SOCKBUF_UNLOCK(&so->so_snd); goto skip_all_send; } } if (rsm || sack_rxmit) counter_u64_add(rack_nfto_resend, 1); else counter_u64_add(rack_non_fto_send, 1); if ((flags & TH_FIN) && sbavail(sb)) { /* * We do not transmit a FIN * with data outstanding. We * need to make it so all data * is acked first. */ flags &= ~TH_FIN; } /* Enforce stack imposed max seg size if we have one */ if (rack->r_ctl.rc_pace_max_segs && (len > rack->r_ctl.rc_pace_max_segs)) { mark = 1; len = rack->r_ctl.rc_pace_max_segs; } SOCKBUF_LOCK_ASSERT(sb); if (len > 0) { if (len >= segsiz) tp->t_flags2 |= TF2_PLPMTU_MAXSEGSNT; else tp->t_flags2 &= ~TF2_PLPMTU_MAXSEGSNT; } /* * Before ESTABLISHED, force sending of initial options unless TCP * set not to do any options. NOTE: we assume that the IP/TCP header * plus TCP options always fit in a single mbuf, leaving room for a * maximum link header, i.e. max_linkhdr + sizeof (struct tcpiphdr) * + optlen <= MCLBYTES */ optlen = 0; #ifdef INET6 if (isipv6) hdrlen = sizeof(struct ip6_hdr) + sizeof(struct tcphdr); else #endif hdrlen = sizeof(struct tcpiphdr); /* * Compute options for segment. We only have to care about SYN and * established connection segments. Options for SYN-ACK segments * are handled in TCP syncache. */ to.to_flags = 0; if ((tp->t_flags & TF_NOOPT) == 0) { /* Maximum segment size. */ if (flags & TH_SYN) { tp->snd_nxt = tp->iss; to.to_mss = tcp_mssopt(&inp->inp_inc); if (tp->t_port) to.to_mss -= V_tcp_udp_tunneling_overhead; to.to_flags |= TOF_MSS; /* * On SYN or SYN|ACK transmits on TFO connections, * only include the TFO option if it is not a * retransmit, as the presence of the TFO option may * have caused the original SYN or SYN|ACK to have * been dropped by a middlebox. */ if (IS_FASTOPEN(tp->t_flags) && (tp->t_rxtshift == 0)) { if (tp->t_state == TCPS_SYN_RECEIVED) { to.to_tfo_len = TCP_FASTOPEN_COOKIE_LEN; to.to_tfo_cookie = (u_int8_t *)&tp->t_tfo_cookie.server; to.to_flags |= TOF_FASTOPEN; wanted_cookie = 1; } else if (tp->t_state == TCPS_SYN_SENT) { to.to_tfo_len = tp->t_tfo_client_cookie_len; to.to_tfo_cookie = tp->t_tfo_cookie.client; to.to_flags |= TOF_FASTOPEN; wanted_cookie = 1; /* * If we wind up having more data to * send with the SYN than can fit in * one segment, don't send any more * until the SYN|ACK comes back from * the other end. */ sendalot = 0; } } } /* Window scaling. */ if ((flags & TH_SYN) && (tp->t_flags & TF_REQ_SCALE)) { to.to_wscale = tp->request_r_scale; to.to_flags |= TOF_SCALE; } /* Timestamps. */ if ((tp->t_flags & TF_RCVD_TSTMP) || ((flags & TH_SYN) && (tp->t_flags & TF_REQ_TSTMP))) { to.to_tsval = ms_cts + tp->ts_offset; to.to_tsecr = tp->ts_recent; to.to_flags |= TOF_TS; } /* Set receive buffer autosizing timestamp. */ if (tp->rfbuf_ts == 0 && (so->so_rcv.sb_flags & SB_AUTOSIZE)) tp->rfbuf_ts = tcp_ts_getticks(); /* Selective ACK's. */ if (tp->t_flags & TF_SACK_PERMIT) { if (flags & TH_SYN) to.to_flags |= TOF_SACKPERM; else if (TCPS_HAVEESTABLISHED(tp->t_state) && tp->rcv_numsacks > 0) { to.to_flags |= TOF_SACK; to.to_nsacks = tp->rcv_numsacks; to.to_sacks = (u_char *)tp->sackblks; } } #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) /* TCP-MD5 (RFC2385). */ if (tp->t_flags & TF_SIGNATURE) to.to_flags |= TOF_SIGNATURE; #endif /* Processing the options. */ hdrlen += optlen = tcp_addoptions(&to, opt); /* * If we wanted a TFO option to be added, but it was unable * to fit, ensure no data is sent. */ if (IS_FASTOPEN(tp->t_flags) && wanted_cookie && !(to.to_flags & TOF_FASTOPEN)) len = 0; } if (tp->t_port) { if (V_tcp_udp_tunneling_port == 0) { /* The port was removed?? */ SOCKBUF_UNLOCK(&so->so_snd); #ifdef TCP_ACCOUNTING crtsc = get_cyclecount(); if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[SND_OUT_FAIL]++; } if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_proc_time[SND_OUT_FAIL] += (crtsc - ts_val); } sched_unpin(); #endif return (EHOSTUNREACH); } hdrlen += sizeof(struct udphdr); } #ifdef INET6 if (isipv6) ipoptlen = ip6_optlen(inp); else #endif if (inp->inp_options) ipoptlen = inp->inp_options->m_len - offsetof(struct ipoption, ipopt_list); else ipoptlen = 0; #if defined(IPSEC) || defined(IPSEC_SUPPORT) ipoptlen += ipsec_optlen; #endif /* * Adjust data length if insertion of options will bump the packet * length beyond the t_maxseg length. Clear the FIN bit because we * cut off the tail of the segment. */ if (len + optlen + ipoptlen > tp->t_maxseg) { if (tso) { uint32_t if_hw_tsomax; uint32_t moff; int32_t max_len; /* extract TSO information */ if_hw_tsomax = tp->t_tsomax; if_hw_tsomaxsegcount = tp->t_tsomaxsegcount; if_hw_tsomaxsegsize = tp->t_tsomaxsegsize; KASSERT(ipoptlen == 0, ("%s: TSO can't do IP options", __func__)); /* * Check if we should limit by maximum payload * length: */ if (if_hw_tsomax != 0) { /* compute maximum TSO length */ max_len = (if_hw_tsomax - hdrlen - max_linkhdr); if (max_len <= 0) { len = 0; } else if (len > max_len) { sendalot = 1; len = max_len; mark = 2; } } /* * Prevent the last segment from being fractional * unless the send sockbuf can be emptied: */ max_len = (tp->t_maxseg - optlen); if ((sb_offset + len) < sbavail(sb)) { moff = len % (u_int)max_len; if (moff != 0) { mark = 3; len -= moff; } } /* * In case there are too many small fragments don't * use TSO: */ if (len <= max_len) { mark = 4; tso = 0; } /* * Send the FIN in a separate segment after the bulk * sending is done. We don't trust the TSO * implementations to clear the FIN flag on all but * the last segment. */ if (tp->t_flags & TF_NEEDFIN) { sendalot = 4; } } else { mark = 5; if (optlen + ipoptlen >= tp->t_maxseg) { /* * Since we don't have enough space to put * the IP header chain and the TCP header in * one packet as required by RFC 7112, don't * send it. Also ensure that at least one * byte of the payload can be put into the * TCP segment. */ SOCKBUF_UNLOCK(&so->so_snd); error = EMSGSIZE; sack_rxmit = 0; goto out; } len = tp->t_maxseg - optlen - ipoptlen; sendalot = 5; } } else { tso = 0; mark = 6; } KASSERT(len + hdrlen + ipoptlen <= IP_MAXPACKET, ("%s: len > IP_MAXPACKET", __func__)); #ifdef DIAGNOSTIC #ifdef INET6 if (max_linkhdr + hdrlen > MCLBYTES) #else if (max_linkhdr + hdrlen > MHLEN) #endif panic("tcphdr too big"); #endif /* * This KASSERT is here to catch edge cases at a well defined place. * Before, those had triggered (random) panic conditions further * down. */ KASSERT(len >= 0, ("[%s:%d]: len < 0", __func__, __LINE__)); if ((len == 0) && (flags & TH_FIN) && (sbused(sb))) { /* * We have outstanding data, don't send a fin by itself!. */ goto just_return; } /* * Grab a header mbuf, attaching a copy of data to be transmitted, * and initialize the header from the template for sends on this * connection. */ hw_tls = tp->t_nic_ktls_xmit != 0; if (len) { uint32_t max_val; uint32_t moff; if (rack->r_ctl.rc_pace_max_segs) max_val = rack->r_ctl.rc_pace_max_segs; else if (rack->rc_user_set_max_segs) max_val = rack->rc_user_set_max_segs * segsiz; else max_val = len; /* * We allow a limit on sending with hptsi. */ if (len > max_val) { mark = 7; len = max_val; } #ifdef INET6 if (MHLEN < hdrlen + max_linkhdr) m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); else #endif m = m_gethdr(M_NOWAIT, MT_DATA); if (m == NULL) { SOCKBUF_UNLOCK(sb); error = ENOBUFS; sack_rxmit = 0; goto out; } m->m_data += max_linkhdr; m->m_len = hdrlen; /* * Start the m_copy functions from the closest mbuf to the * sb_offset in the socket buffer chain. */ mb = sbsndptr_noadv(sb, sb_offset, &moff); s_mb = mb; s_moff = moff; if (len <= MHLEN - hdrlen - max_linkhdr && !hw_tls) { m_copydata(mb, moff, (int)len, mtod(m, caddr_t)+hdrlen); if (SEQ_LT(tp->snd_nxt, tp->snd_max)) sbsndptr_adv(sb, mb, len); m->m_len += len; } else { struct sockbuf *msb; if (SEQ_LT(tp->snd_nxt, tp->snd_max)) msb = NULL; else msb = sb; m->m_next = tcp_m_copym( mb, moff, &len, if_hw_tsomaxsegcount, if_hw_tsomaxsegsize, msb, ((rsm == NULL) ? hw_tls : 0) #ifdef NETFLIX_COPY_ARGS , &s_mb, &s_moff #endif ); if (len <= (tp->t_maxseg - optlen)) { /* * Must have ran out of mbufs for the copy * shorten it to no longer need tso. Lets * not put on sendalot since we are low on * mbufs. */ tso = 0; } if (m->m_next == NULL) { SOCKBUF_UNLOCK(sb); (void)m_free(m); error = ENOBUFS; sack_rxmit = 0; goto out; } } if (SEQ_LT(tp->snd_nxt, tp->snd_max) || sack_rxmit) { if (rsm && (rsm->r_flags & RACK_TLP)) { /* * TLP should not count in retran count, but * in its own bin */ counter_u64_add(rack_tlp_retran, 1); counter_u64_add(rack_tlp_retran_bytes, len); } else { tp->t_sndrexmitpack++; KMOD_TCPSTAT_INC(tcps_sndrexmitpack); KMOD_TCPSTAT_ADD(tcps_sndrexmitbyte, len); } #ifdef STATS stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_RETXPB, len); #endif } else { KMOD_TCPSTAT_INC(tcps_sndpack); KMOD_TCPSTAT_ADD(tcps_sndbyte, len); #ifdef STATS stats_voi_update_abs_u64(tp->t_stats, VOI_TCP_TXPB, len); #endif } /* * If we're sending everything we've got, set PUSH. (This * will keep happy those implementations which only give * data to the user when a buffer fills or a PUSH comes in.) */ if (sb_offset + len == sbused(sb) && sbused(sb) && !(flags & TH_SYN)) { flags |= TH_PUSH; add_flag |= RACK_HAD_PUSH; } SOCKBUF_UNLOCK(sb); } else { SOCKBUF_UNLOCK(sb); if (tp->t_flags & TF_ACKNOW) KMOD_TCPSTAT_INC(tcps_sndacks); else if (flags & (TH_SYN | TH_FIN | TH_RST)) KMOD_TCPSTAT_INC(tcps_sndctrl); else KMOD_TCPSTAT_INC(tcps_sndwinup); m = m_gethdr(M_NOWAIT, MT_DATA); if (m == NULL) { error = ENOBUFS; sack_rxmit = 0; goto out; } #ifdef INET6 if (isipv6 && (MHLEN < hdrlen + max_linkhdr) && MHLEN >= hdrlen) { M_ALIGN(m, hdrlen); } else #endif m->m_data += max_linkhdr; m->m_len = hdrlen; } SOCKBUF_UNLOCK_ASSERT(sb); m->m_pkthdr.rcvif = (struct ifnet *)0; #ifdef MAC mac_inpcb_create_mbuf(inp, m); #endif if ((ipoptlen == 0) && (rack->r_ctl.fsb.tcp_ip_hdr) && rack->r_fsb_inited) { #ifdef INET6 if (isipv6) ip6 = (struct ip6_hdr *)rack->r_ctl.fsb.tcp_ip_hdr; else #endif /* INET6 */ #ifdef INET ip = (struct ip *)rack->r_ctl.fsb.tcp_ip_hdr; #endif th = rack->r_ctl.fsb.th; udp = rack->r_ctl.fsb.udp; if (udp) { #ifdef INET6 if (isipv6) ulen = hdrlen + len - sizeof(struct ip6_hdr); else #endif /* INET6 */ ulen = hdrlen + len - sizeof(struct ip); udp->uh_ulen = htons(ulen); } } else { #ifdef INET6 if (isipv6) { ip6 = mtod(m, struct ip6_hdr *); if (tp->t_port) { udp = (struct udphdr *)((caddr_t)ip6 + sizeof(struct ip6_hdr)); udp->uh_sport = htons(V_tcp_udp_tunneling_port); udp->uh_dport = tp->t_port; ulen = hdrlen + len - sizeof(struct ip6_hdr); udp->uh_ulen = htons(ulen); th = (struct tcphdr *)(udp + 1); } else th = (struct tcphdr *)(ip6 + 1); tcpip_fillheaders(inp, tp->t_port, ip6, th); } else #endif /* INET6 */ { #ifdef INET ip = mtod(m, struct ip *); if (tp->t_port) { udp = (struct udphdr *)((caddr_t)ip + sizeof(struct ip)); udp->uh_sport = htons(V_tcp_udp_tunneling_port); udp->uh_dport = tp->t_port; ulen = hdrlen + len - sizeof(struct ip); udp->uh_ulen = htons(ulen); th = (struct tcphdr *)(udp + 1); } else th = (struct tcphdr *)(ip + 1); tcpip_fillheaders(inp, tp->t_port, ip, th); #endif } } /* * Fill in fields, remembering maximum advertised window for use in * delaying messages about window sizes. If resending a FIN, be sure * not to use a new sequence number. */ if (flags & TH_FIN && tp->t_flags & TF_SENTFIN && tp->snd_nxt == tp->snd_max) tp->snd_nxt--; /* * If we are starting a connection, send ECN setup SYN packet. If we * are on a retransmit, we may resend those bits a number of times * as per RFC 3168. */ if (tp->t_state == TCPS_SYN_SENT && V_tcp_do_ecn) { flags |= tcp_ecn_output_syn_sent(tp); } /* Also handle parallel SYN for ECN */ if (TCPS_HAVERCVDSYN(tp->t_state) && (tp->t_flags2 & (TF2_ECN_PERMIT | TF2_ACE_PERMIT))) { int ect = tcp_ecn_output_established(tp, &flags, len, sack_rxmit); if ((tp->t_state == TCPS_SYN_RECEIVED) && (tp->t_flags2 & TF2_ECN_SND_ECE)) tp->t_flags2 &= ~TF2_ECN_SND_ECE; #ifdef INET6 if (isipv6) { ip6->ip6_flow &= ~htonl(IPTOS_ECN_MASK << 20); ip6->ip6_flow |= htonl(ect << 20); } else #endif { #ifdef INET ip->ip_tos &= ~IPTOS_ECN_MASK; ip->ip_tos |= ect; #endif } } /* * If we are doing retransmissions, then snd_nxt will not reflect * the first unsent octet. For ACK only packets, we do not want the * sequence number of the retransmitted packet, we want the sequence * number of the next unsent octet. So, if there is no data (and no * SYN or FIN), use snd_max instead of snd_nxt when filling in * ti_seq. But if we are in persist state, snd_max might reflect * one byte beyond the right edge of the window, so use snd_nxt in * that case, since we know we aren't doing a retransmission. * (retransmit and persist are mutually exclusive...) */ if (sack_rxmit == 0) { if (len || (flags & (TH_SYN | TH_FIN))) { th->th_seq = htonl(tp->snd_nxt); rack_seq = tp->snd_nxt; } else { th->th_seq = htonl(tp->snd_max); rack_seq = tp->snd_max; } } else { th->th_seq = htonl(rsm->r_start); rack_seq = rsm->r_start; } th->th_ack = htonl(tp->rcv_nxt); tcp_set_flags(th, flags); /* * Calculate receive window. Don't shrink window, but avoid silly * window syndrome. * If a RST segment is sent, advertise a window of zero. */ if (flags & TH_RST) { recwin = 0; } else { if (recwin < (long)(so->so_rcv.sb_hiwat / 4) && recwin < (long)segsiz) { recwin = 0; } if (SEQ_GT(tp->rcv_adv, tp->rcv_nxt) && recwin < (long)(tp->rcv_adv - tp->rcv_nxt)) recwin = (long)(tp->rcv_adv - tp->rcv_nxt); } /* * According to RFC1323 the window field in a SYN (i.e., a or * ) segment itself is never scaled. The case is * handled in syncache. */ if (flags & TH_SYN) th->th_win = htons((u_short) (min(sbspace(&so->so_rcv), TCP_MAXWIN))); else { /* Avoid shrinking window with window scaling. */ recwin = roundup2(recwin, 1 << tp->rcv_scale); th->th_win = htons((u_short)(recwin >> tp->rcv_scale)); } /* * Adjust the RXWIN0SENT flag - indicate that we have advertised a 0 * window. This may cause the remote transmitter to stall. This * flag tells soreceive() to disable delayed acknowledgements when * draining the buffer. This can occur if the receiver is * attempting to read more data than can be buffered prior to * transmitting on the connection. */ if (th->th_win == 0) { tp->t_sndzerowin++; tp->t_flags |= TF_RXWIN0SENT; } else tp->t_flags &= ~TF_RXWIN0SENT; tp->snd_up = tp->snd_una; /* drag it along, its deprecated */ /* Now are we using fsb?, if so copy the template data to the mbuf */ if ((ipoptlen == 0) && (rack->r_ctl.fsb.tcp_ip_hdr) && rack->r_fsb_inited) { uint8_t *cpto; cpto = mtod(m, uint8_t *); memcpy(cpto, rack->r_ctl.fsb.tcp_ip_hdr, rack->r_ctl.fsb.tcp_ip_hdr_len); /* * We have just copied in: * IP/IP6 * * tcphdr (no options) * * We need to grab the correct pointers into the mbuf * for both the tcp header, and possibly the udp header (if tunneling). * We do this by using the offset in the copy buffer and adding it * to the mbuf base pointer (cpto). */ #ifdef INET6 if (isipv6) ip6 = mtod(m, struct ip6_hdr *); else #endif /* INET6 */ #ifdef INET ip = mtod(m, struct ip *); #endif th = (struct tcphdr *)(cpto + ((uint8_t *)rack->r_ctl.fsb.th - rack->r_ctl.fsb.tcp_ip_hdr)); /* If we have a udp header lets set it into the mbuf as well */ if (udp) udp = (struct udphdr *)(cpto + ((uint8_t *)rack->r_ctl.fsb.udp - rack->r_ctl.fsb.tcp_ip_hdr)); } if (optlen) { bcopy(opt, th + 1, optlen); th->th_off = (sizeof(struct tcphdr) + optlen) >> 2; } /* * Put TCP length in extended header, and then checksum extended * header and data. */ m->m_pkthdr.len = hdrlen + len; /* in6_cksum() need this */ #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) if (to.to_flags & TOF_SIGNATURE) { /* * Calculate MD5 signature and put it into the place * determined before. * NOTE: since TCP options buffer doesn't point into * mbuf's data, calculate offset and use it. */ if (!TCPMD5_ENABLED() || TCPMD5_OUTPUT(m, th, (u_char *)(th + 1) + (to.to_signature - opt)) != 0) { /* * Do not send segment if the calculation of MD5 * digest has failed. */ goto out; } } #endif #ifdef INET6 if (isipv6) { /* * ip6_plen is not need to be filled now, and will be filled * in ip6_output. */ if (tp->t_port) { m->m_pkthdr.csum_flags = CSUM_UDP_IPV6; m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); udp->uh_sum = in6_cksum_pseudo(ip6, ulen, IPPROTO_UDP, 0); th->th_sum = htons(0); UDPSTAT_INC(udps_opackets); } else { m->m_pkthdr.csum_flags = CSUM_TCP_IPV6; m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); th->th_sum = in6_cksum_pseudo(ip6, sizeof(struct tcphdr) + optlen + len, IPPROTO_TCP, 0); } } #endif #if defined(INET6) && defined(INET) else #endif #ifdef INET { if (tp->t_port) { m->m_pkthdr.csum_flags = CSUM_UDP; m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); udp->uh_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, htons(ulen + IPPROTO_UDP)); th->th_sum = htons(0); UDPSTAT_INC(udps_opackets); } else { m->m_pkthdr.csum_flags = CSUM_TCP; m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); th->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, htons(sizeof(struct tcphdr) + IPPROTO_TCP + len + optlen)); } /* IP version must be set here for ipv4/ipv6 checking later */ KASSERT(ip->ip_v == IPVERSION, ("%s: IP version incorrect: %d", __func__, ip->ip_v)); } #endif /* * Enable TSO and specify the size of the segments. The TCP pseudo * header checksum is always provided. XXX: Fixme: This is currently * not the case for IPv6. */ if (tso) { /* * Here we must use t_maxseg and the optlen since * the optlen may include SACK's (or DSACK). */ KASSERT(len > tp->t_maxseg - optlen, ("%s: len <= tso_segsz", __func__)); m->m_pkthdr.csum_flags |= CSUM_TSO; m->m_pkthdr.tso_segsz = tp->t_maxseg - optlen; } KASSERT(len + hdrlen == m_length(m, NULL), ("%s: mbuf chain different than expected: %d + %u != %u", __func__, len, hdrlen, m_length(m, NULL))); #ifdef TCP_HHOOK /* Run HHOOK_TCP_ESTABLISHED_OUT helper hooks. */ hhook_run_tcp_est_out(tp, th, &to, len, tso); #endif if ((rack->r_ctl.crte != NULL) && (rack->rc_hw_nobuf == 0) && tcp_bblogging_on(tp)) { rack_log_queue_level(tp, rack, len, &tv, cts); } /* We're getting ready to send; log now. */ if (tcp_bblogging_on(rack->rc_tp)) { union tcp_log_stackspecific log; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.inhpts = tcp_in_hpts(rack->rc_tp); if (rack->rack_no_prr) log.u_bbr.flex1 = 0; else log.u_bbr.flex1 = rack->r_ctl.rc_prr_sndcnt; log.u_bbr.flex2 = rack->r_ctl.rc_pace_min_segs; log.u_bbr.flex3 = rack->r_ctl.rc_pace_max_segs; log.u_bbr.flex4 = orig_len; /* Save off the early/late values */ log.u_bbr.flex6 = rack->r_ctl.rc_agg_early; log.u_bbr.applimited = rack->r_ctl.rc_agg_delayed; log.u_bbr.bw_inuse = rack_get_bw(rack); log.u_bbr.cur_del_rate = rack->r_ctl.gp_bw; log.u_bbr.flex8 = 0; if (rsm) { if (rsm->r_flags & RACK_RWND_COLLAPSED) { rack_log_collapse(rack, rsm->r_start, rsm->r_end, 0, __LINE__, 5, rsm->r_flags, rsm); counter_u64_add(rack_collapsed_win_rxt, 1); counter_u64_add(rack_collapsed_win_rxt_bytes, (rsm->r_end - rsm->r_start)); } if (doing_tlp) log.u_bbr.flex8 = 2; else log.u_bbr.flex8 = 1; } else { if (doing_tlp) log.u_bbr.flex8 = 3; } log.u_bbr.pacing_gain = rack_get_output_gain(rack, rsm); log.u_bbr.flex7 = mark; log.u_bbr.flex7 <<= 8; log.u_bbr.flex7 |= pass; log.u_bbr.pkts_out = tp->t_maxseg; log.u_bbr.timeStamp = cts; log.u_bbr.inflight = ctf_flight_size(rack->rc_tp, rack->r_ctl.rc_sacked); if (rsm && (rsm->r_rtr_cnt > 0)) { /* * When we have a retransmit we want to log the * burst at send and flight at send from before. */ log.u_bbr.flex5 = rsm->r_fas; log.u_bbr.bbr_substate = rsm->r_bas; } else { /* * New transmits we log in flex5 the inflight again as * well as the number of segments in our send in the * substate field. */ log.u_bbr.flex5 = log.u_bbr.inflight; log.u_bbr.bbr_substate = (uint8_t)((len + segsiz - 1)/segsiz); } log.u_bbr.lt_epoch = cwnd_to_use; log.u_bbr.delivered = sendalot; log.u_bbr.rttProp = (uint64_t)rsm; log.u_bbr.pkt_epoch = __LINE__; if (rsm) { log.u_bbr.delRate = rsm->r_flags; log.u_bbr.delRate <<= 31; log.u_bbr.delRate |= rack->r_must_retran; log.u_bbr.delRate <<= 1; log.u_bbr.delRate |= (sack_rxmit & 0x00000001); } else { log.u_bbr.delRate = rack->r_must_retran; log.u_bbr.delRate <<= 1; log.u_bbr.delRate |= (sack_rxmit & 0x00000001); } lgb = tcp_log_event(tp, th, &so->so_rcv, &so->so_snd, TCP_LOG_OUT, ERRNO_UNK, len, &log, false, NULL, __func__, __LINE__, &tv); } else lgb = NULL; /* * Fill in IP length and desired time to live and send to IP level. * There should be a better way to handle ttl and tos; we could keep * them in the template, but need a way to checksum without them. */ /* * m->m_pkthdr.len should have been set before cksum calcuration, * because in6_cksum() need it. */ #ifdef INET6 if (isipv6) { /* * we separately set hoplimit for every segment, since the * user might want to change the value via setsockopt. Also, * desired default hop limit might be changed via Neighbor * Discovery. */ rack->r_ctl.fsb.hoplimit = ip6->ip6_hlim = in6_selecthlim(inp, NULL); /* * Set the packet size here for the benefit of DTrace * probes. ip6_output() will set it properly; it's supposed * to include the option header lengths as well. */ ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(*ip6)); if (V_path_mtu_discovery && tp->t_maxseg > V_tcp_minmss) tp->t_flags2 |= TF2_PLPMTU_PMTUD; else tp->t_flags2 &= ~TF2_PLPMTU_PMTUD; if (tp->t_state == TCPS_SYN_SENT) TCP_PROBE5(connect__request, NULL, tp, ip6, tp, th); TCP_PROBE5(send, NULL, tp, ip6, tp, th); /* TODO: IPv6 IP6TOS_ECT bit on */ error = ip6_output(m, inp->in6p_outputopts, &inp->inp_route6, ((rsm || sack_rxmit) ? IP_NO_SND_TAG_RL : 0), NULL, NULL, inp); if (error == EMSGSIZE && inp->inp_route6.ro_nh != NULL) mtu = inp->inp_route6.ro_nh->nh_mtu; } #endif /* INET6 */ #if defined(INET) && defined(INET6) else #endif #ifdef INET { ip->ip_len = htons(m->m_pkthdr.len); #ifdef INET6 if (inp->inp_vflag & INP_IPV6PROTO) ip->ip_ttl = in6_selecthlim(inp, NULL); #endif /* INET6 */ rack->r_ctl.fsb.hoplimit = ip->ip_ttl; /* * If we do path MTU discovery, then we set DF on every * packet. This might not be the best thing to do according * to RFC3390 Section 2. However the tcp hostcache migitates * the problem so it affects only the first tcp connection * with a host. * * NB: Don't set DF on small MTU/MSS to have a safe * fallback. */ if (V_path_mtu_discovery && tp->t_maxseg > V_tcp_minmss) { tp->t_flags2 |= TF2_PLPMTU_PMTUD; if (tp->t_port == 0 || len < V_tcp_minmss) { ip->ip_off |= htons(IP_DF); } } else { tp->t_flags2 &= ~TF2_PLPMTU_PMTUD; } if (tp->t_state == TCPS_SYN_SENT) TCP_PROBE5(connect__request, NULL, tp, ip, tp, th); TCP_PROBE5(send, NULL, tp, ip, tp, th); error = ip_output(m, #if defined(IPSEC) || defined(IPSEC_SUPPORT) inp->inp_options, #else NULL, #endif &inp->inp_route, ((rsm || sack_rxmit) ? IP_NO_SND_TAG_RL : 0), 0, inp); if (error == EMSGSIZE && inp->inp_route.ro_nh != NULL) mtu = inp->inp_route.ro_nh->nh_mtu; } #endif /* INET */ out: if (lgb) { lgb->tlb_errno = error; lgb = NULL; } /* * In transmit state, time the transmission and arrange for the * retransmit. In persist state, just set snd_max. */ rack_log_output(tp, &to, len, rack_seq, (uint8_t) flags, error, rack_to_usec_ts(&tv), rsm, add_flag, s_mb, s_moff, hw_tls, segsiz); if (error == 0) { if (rsm == NULL) { if (rack->lt_bw_up == 0) { rack->r_ctl.lt_timemark = tcp_tv_to_lusectick(&tv); rack->r_ctl.lt_seq = tp->snd_una; rack->lt_bw_up = 1; } else if (((rack_seq + len) - rack->r_ctl.lt_seq) > 0x7fffffff) { /* * Need to record what we have since we are * approaching seq wrap. */ uint64_t tmark; rack->r_ctl.lt_bw_bytes += (tp->snd_una - rack->r_ctl.lt_seq); rack->r_ctl.lt_seq = tp->snd_una; tmark = tcp_tv_to_lusectick(&tv); rack->r_ctl.lt_bw_time += (tmark - rack->r_ctl.lt_timemark); rack->r_ctl.lt_timemark = tmark; } } rack->forced_ack = 0; /* If we send something zap the FA flag */ counter_u64_add(rack_total_bytes, len); tcp_account_for_send(tp, len, (rsm != NULL), doing_tlp, hw_tls); if (rsm && doing_tlp) { rack->rc_last_sent_tlp_past_cumack = 0; rack->rc_last_sent_tlp_seq_valid = 1; rack->r_ctl.last_sent_tlp_seq = rsm->r_start; rack->r_ctl.last_sent_tlp_len = rsm->r_end - rsm->r_start; } if (rack->rc_hw_nobuf) { rack->rc_hw_nobuf = 0; rack->r_ctl.rc_agg_delayed = 0; rack->r_early = 0; rack->r_late = 0; rack->r_ctl.rc_agg_early = 0; } if (rsm && (doing_tlp == 0)) { /* Set we retransmitted */ rack->rc_gp_saw_rec = 1; } else { if (cwnd_to_use > tp->snd_ssthresh) { /* Set we sent in CA */ rack->rc_gp_saw_ca = 1; } else { /* Set we sent in SS */ rack->rc_gp_saw_ss = 1; } } if (TCPS_HAVEESTABLISHED(tp->t_state) && (tp->t_flags & TF_SACK_PERMIT) && tp->rcv_numsacks > 0) tcp_clean_dsack_blocks(tp); tot_len_this_send += len; if (len == 0) { counter_u64_add(rack_out_size[TCP_MSS_ACCT_SNDACK], 1); } else { int idx; idx = (len / segsiz) + 3; if (idx >= TCP_MSS_ACCT_ATIMER) counter_u64_add(rack_out_size[(TCP_MSS_ACCT_ATIMER-1)], 1); else counter_u64_add(rack_out_size[idx], 1); } } if ((rack->rack_no_prr == 0) && sub_from_prr && (error == 0)) { if (rack->r_ctl.rc_prr_sndcnt >= len) rack->r_ctl.rc_prr_sndcnt -= len; else rack->r_ctl.rc_prr_sndcnt = 0; } sub_from_prr = 0; if (doing_tlp) { /* Make sure the TLP is added */ add_flag |= RACK_TLP; } else if (rsm) { /* If its a resend without TLP then it must not have the flag */ rsm->r_flags &= ~RACK_TLP; } if ((error == 0) && (len > 0) && (tp->snd_una == tp->snd_max)) rack->r_ctl.rc_tlp_rxt_last_time = cts; { tcp_seq startseq = tp->snd_nxt; /* Track our lost count */ if (rsm && (doing_tlp == 0)) rack->r_ctl.rc_loss_count += rsm->r_end - rsm->r_start; /* * Advance snd_nxt over sequence space of this segment. */ if (error) /* We don't log or do anything with errors */ goto nomore; if (doing_tlp == 0) { if (rsm == NULL) { /* * Not a retransmission of some * sort, new data is going out so * clear our TLP count and flag. */ rack->rc_tlp_in_progress = 0; rack->r_ctl.rc_tlp_cnt_out = 0; } } else { /* * We have just sent a TLP, mark that it is true * and make sure our in progress is set so we * continue to check the count. */ rack->rc_tlp_in_progress = 1; rack->r_ctl.rc_tlp_cnt_out++; } if (flags & (TH_SYN | TH_FIN)) { if (flags & TH_SYN) tp->snd_nxt++; if (flags & TH_FIN) { tp->snd_nxt++; tp->t_flags |= TF_SENTFIN; } } /* In the ENOBUFS case we do *not* update snd_max */ if (sack_rxmit) goto nomore; tp->snd_nxt += len; if (SEQ_GT(tp->snd_nxt, tp->snd_max)) { if (tp->snd_una == tp->snd_max) { /* * Update the time we just added data since * none was outstanding. */ rack_log_progress_event(rack, tp, ticks, PROGRESS_START, __LINE__); tp->t_acktime = ticks; } tp->snd_max = tp->snd_nxt; if (rack->rc_new_rnd_needed) { /* * Update the rnd to start ticking not * that from a time perspective all of * the preceding idle time is "in the round" */ rack->rc_new_rnd_needed = 0; rack->r_ctl.roundends = tp->snd_max; } /* * Time this transmission if not a retransmission and * not currently timing anything. * This is only relevant in case of switching back to * the base stack. */ if (tp->t_rtttime == 0) { tp->t_rtttime = ticks; tp->t_rtseq = startseq; KMOD_TCPSTAT_INC(tcps_segstimed); } if (len && ((tp->t_flags & TF_GPUTINPROG) == 0)) rack_start_gp_measurement(tp, rack, startseq, sb_offset); } /* * If we are doing FO we need to update the mbuf position and subtract * this happens when the peer sends us duplicate information and * we thus want to send a DSACK. * * XXXRRS: This brings to mind a ?, when we send a DSACK block is TSO * turned off? If not then we are going to echo multiple DSACK blocks * out (with the TSO), which we should not be doing. */ if (rack->r_fast_output && len) { if (rack->r_ctl.fsb.left_to_send > len) rack->r_ctl.fsb.left_to_send -= len; else rack->r_ctl.fsb.left_to_send = 0; if (rack->r_ctl.fsb.left_to_send < segsiz) rack->r_fast_output = 0; if (rack->r_fast_output) { rack->r_ctl.fsb.m = sbsndmbuf(sb, (tp->snd_max - tp->snd_una), &rack->r_ctl.fsb.off); rack->r_ctl.fsb.o_m_len = rack->r_ctl.fsb.m->m_len; rack->r_ctl.fsb.o_t_len = M_TRAILINGROOM(rack->r_ctl.fsb.m); } } } nomore: if (error) { rack->r_ctl.rc_agg_delayed = 0; rack->r_early = 0; rack->r_late = 0; rack->r_ctl.rc_agg_early = 0; SOCKBUF_UNLOCK_ASSERT(sb); /* Check gotos. */ /* * Failures do not advance the seq counter above. For the * case of ENOBUFS we will fall out and retry in 1ms with * the hpts. Everything else will just have to retransmit * with the timer. * * In any case, we do not want to loop around for another * send without a good reason. */ sendalot = 0; switch (error) { case EPERM: tp->t_softerror = error; #ifdef TCP_ACCOUNTING crtsc = get_cyclecount(); if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[SND_OUT_FAIL]++; } if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_proc_time[SND_OUT_FAIL] += (crtsc - ts_val); } sched_unpin(); #endif return (error); case ENOBUFS: /* * Pace us right away to retry in a some * time */ if (rack->r_ctl.crte != NULL) { tcp_trace_point(rack->rc_tp, TCP_TP_HWENOBUF); if (tcp_bblogging_on(rack->rc_tp)) rack_log_queue_level(tp, rack, len, &tv, cts); } else tcp_trace_point(rack->rc_tp, TCP_TP_ENOBUF); slot = ((1 + rack->rc_enobuf) * HPTS_USEC_IN_MSEC); if (rack->rc_enobuf < 0x7f) rack->rc_enobuf++; if (slot < (10 * HPTS_USEC_IN_MSEC)) slot = 10 * HPTS_USEC_IN_MSEC; if (rack->r_ctl.crte != NULL) { counter_u64_add(rack_saw_enobuf_hw, 1); tcp_rl_log_enobuf(rack->r_ctl.crte); } counter_u64_add(rack_saw_enobuf, 1); goto enobufs; case EMSGSIZE: /* * For some reason the interface we used initially * to send segments changed to another or lowered * its MTU. If TSO was active we either got an * interface without TSO capabilits or TSO was * turned off. If we obtained mtu from ip_output() * then update it and try again. */ if (tso) tp->t_flags &= ~TF_TSO; if (mtu != 0) { int saved_mtu; saved_mtu = tp->t_maxseg; tcp_mss_update(tp, -1, mtu, NULL, NULL); if (saved_mtu > tp->t_maxseg) { goto again; } } slot = 10 * HPTS_USEC_IN_MSEC; rack_start_hpts_timer(rack, tp, cts, slot, 0, 0); #ifdef TCP_ACCOUNTING crtsc = get_cyclecount(); if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[SND_OUT_FAIL]++; } if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_proc_time[SND_OUT_FAIL] += (crtsc - ts_val); } sched_unpin(); #endif return (error); case ENETUNREACH: counter_u64_add(rack_saw_enetunreach, 1); case EHOSTDOWN: case EHOSTUNREACH: case ENETDOWN: if (TCPS_HAVERCVDSYN(tp->t_state)) { tp->t_softerror = error; } /* FALLTHROUGH */ default: slot = 10 * HPTS_USEC_IN_MSEC; rack_start_hpts_timer(rack, tp, cts, slot, 0, 0); #ifdef TCP_ACCOUNTING crtsc = get_cyclecount(); if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[SND_OUT_FAIL]++; } if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_proc_time[SND_OUT_FAIL] += (crtsc - ts_val); } sched_unpin(); #endif return (error); } } else { rack->rc_enobuf = 0; if (IN_FASTRECOVERY(tp->t_flags) && rsm) rack->r_ctl.retran_during_recovery += len; } KMOD_TCPSTAT_INC(tcps_sndtotal); /* * Data sent (as far as we can tell). If this advertises a larger * window than any other segment, then remember the size of the * advertised window. Any pending ACK has now been sent. */ if (recwin > 0 && SEQ_GT(tp->rcv_nxt + recwin, tp->rcv_adv)) tp->rcv_adv = tp->rcv_nxt + recwin; tp->last_ack_sent = tp->rcv_nxt; tp->t_flags &= ~(TF_ACKNOW | TF_DELACK); enobufs: if (sendalot) { /* Do we need to turn off sendalot? */ if (rack->r_ctl.rc_pace_max_segs && (tot_len_this_send >= rack->r_ctl.rc_pace_max_segs)) { /* We hit our max. */ sendalot = 0; } else if ((rack->rc_user_set_max_segs) && (tot_len_this_send >= (rack->rc_user_set_max_segs * segsiz))) { /* We hit the user defined max */ sendalot = 0; } } if ((error == 0) && (flags & TH_FIN)) tcp_log_end_status(tp, TCP_EI_STATUS_SERVER_FIN); if (flags & TH_RST) { /* * We don't send again after sending a RST. */ slot = 0; sendalot = 0; if (error == 0) tcp_log_end_status(tp, TCP_EI_STATUS_SERVER_RST); } else if ((slot == 0) && (sendalot == 0) && tot_len_this_send) { /* * Get our pacing rate, if an error * occurred in sending (ENOBUF) we would * hit the else if with slot preset. Other * errors return. */ slot = rack_get_pacing_delay(rack, tp, tot_len_this_send, rsm, segsiz); } if (rsm && (rsm->r_flags & RACK_HAS_SYN) == 0 && rack->use_rack_rr) { /* Its a retransmit and we use the rack cheat? */ if ((slot == 0) || (rack->rc_always_pace == 0) || (rack->r_rr_config == 1)) { /* * We have no pacing set or we * are using old-style rack or * we are overridden to use the old 1ms pacing. */ slot = rack->r_ctl.rc_min_to; } } /* We have sent clear the flag */ rack->r_ent_rec_ns = 0; if (rack->r_must_retran) { if (rsm) { rack->r_ctl.rc_out_at_rto -= (rsm->r_end - rsm->r_start); if (SEQ_GEQ(rsm->r_end, rack->r_ctl.rc_snd_max_at_rto)) { /* * We have retransmitted all. */ rack->r_must_retran = 0; rack->r_ctl.rc_out_at_rto = 0; } } else if (SEQ_GEQ(tp->snd_max, rack->r_ctl.rc_snd_max_at_rto)) { /* * Sending new data will also kill * the loop. */ rack->r_must_retran = 0; rack->r_ctl.rc_out_at_rto = 0; } } rack->r_ctl.fsb.recwin = recwin; if ((tp->t_flags & (TF_WASCRECOVERY|TF_WASFRECOVERY)) && SEQ_GT(tp->snd_max, rack->r_ctl.rc_snd_max_at_rto)) { /* * We hit an RTO and now have past snd_max at the RTO * clear all the WAS flags. */ tp->t_flags &= ~(TF_WASCRECOVERY|TF_WASFRECOVERY); } if (slot) { /* set the rack tcb into the slot N */ if ((error == 0) && rack_use_rfo && ((flags & (TH_SYN|TH_FIN)) == 0) && (rsm == NULL) && (tp->snd_nxt == tp->snd_max) && (ipoptlen == 0) && (tp->rcv_numsacks == 0) && rack->r_fsb_inited && TCPS_HAVEESTABLISHED(tp->t_state) && ((IN_RECOVERY(tp->t_flags)) == 0) && (rack->r_must_retran == 0) && ((tp->t_flags & TF_NEEDFIN) == 0) && (len > 0) && (orig_len > 0) && (orig_len > len) && ((orig_len - len) >= segsiz) && ((optlen == 0) || ((optlen == TCPOLEN_TSTAMP_APPA) && (to.to_flags & TOF_TS)))) { /* We can send at least one more MSS using our fsb */ rack_setup_fast_output(tp, rack, sb, len, orig_len, segsiz, pace_max_seg, hw_tls, flags); } else rack->r_fast_output = 0; rack_log_fsb(rack, tp, so, flags, ipoptlen, orig_len, len, error, (rsm == NULL), optlen, __LINE__, 2); } else if (sendalot) { int ret; sack_rxmit = 0; if ((error == 0) && rack_use_rfo && ((flags & (TH_SYN|TH_FIN)) == 0) && (rsm == NULL) && (ipoptlen == 0) && (tp->rcv_numsacks == 0) && (tp->snd_nxt == tp->snd_max) && (rack->r_must_retran == 0) && rack->r_fsb_inited && TCPS_HAVEESTABLISHED(tp->t_state) && ((IN_RECOVERY(tp->t_flags)) == 0) && ((tp->t_flags & TF_NEEDFIN) == 0) && (len > 0) && (orig_len > 0) && (orig_len > len) && ((orig_len - len) >= segsiz) && ((optlen == 0) || ((optlen == TCPOLEN_TSTAMP_APPA) && (to.to_flags & TOF_TS)))) { /* we can use fast_output for more */ rack_setup_fast_output(tp, rack, sb, len, orig_len, segsiz, pace_max_seg, hw_tls, flags); if (rack->r_fast_output) { error = 0; ret = rack_fast_output(tp, rack, ts_val, cts, ms_cts, &tv, tot_len_this_send, &error); if (ret >= 0) return (ret); else if (error) goto nomore; } } goto again; } /* Assure when we leave that snd_nxt will point to top */ skip_all_send: if (SEQ_GT(tp->snd_max, tp->snd_nxt)) tp->snd_nxt = tp->snd_max; rack_start_hpts_timer(rack, tp, cts, slot, tot_len_this_send, 0); #ifdef TCP_ACCOUNTING crtsc = get_cyclecount() - ts_val; if (tot_len_this_send) { if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[SND_OUT_DATA]++; } if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_proc_time[SND_OUT_DATA] += crtsc; } if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[CNT_OF_MSS_OUT] += ((tot_len_this_send + segsiz - 1) /segsiz); } } else { if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[SND_OUT_ACK]++; } if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_proc_time[SND_OUT_ACK] += crtsc; } } sched_unpin(); #endif if (error == ENOBUFS) error = 0; return (error); } static void rack_update_seg(struct tcp_rack *rack) { uint32_t orig_val; orig_val = rack->r_ctl.rc_pace_max_segs; rack_set_pace_segments(rack->rc_tp, rack, __LINE__, NULL); if (orig_val != rack->r_ctl.rc_pace_max_segs) rack_log_pacing_delay_calc(rack, 0, 0, orig_val, 0, 0, 15, __LINE__, NULL, 0); } static void rack_mtu_change(struct tcpcb *tp) { /* * The MSS may have changed */ struct tcp_rack *rack; struct rack_sendmap *rsm; rack = (struct tcp_rack *)tp->t_fb_ptr; if (rack->r_ctl.rc_pace_min_segs != ctf_fixed_maxseg(tp)) { /* * The MTU has changed we need to resend everything * since all we have sent is lost. We first fix * up the mtu though. */ rack_set_pace_segments(tp, rack, __LINE__, NULL); /* We treat this like a full retransmit timeout without the cwnd adjustment */ rack_remxt_tmr(tp); rack->r_fast_output = 0; rack->r_ctl.rc_out_at_rto = ctf_flight_size(tp, rack->r_ctl.rc_sacked); rack->r_ctl.rc_snd_max_at_rto = tp->snd_max; rack->r_must_retran = 1; /* Mark all inflight to needing to be rxt'd */ TAILQ_FOREACH(rsm, &rack->r_ctl.rc_tmap, r_tnext) { rsm->r_flags |= (RACK_MUST_RXT|RACK_PMTU_CHG); } } sack_filter_clear(&rack->r_ctl.rack_sf, tp->snd_una); /* We don't use snd_nxt to retransmit */ tp->snd_nxt = tp->snd_max; } static int rack_set_dgp(struct tcp_rack *rack) { /* pace_always=1 */ if (rack->rc_always_pace == 0) { if (tcp_can_enable_pacing() == 0) return (EBUSY); } rack->rc_fillcw_apply_discount = 0; rack->dgp_on = 1; rack->rc_always_pace = 1; rack->use_fixed_rate = 0; if (rack->gp_ready) rack_set_cc_pacing(rack); rack->rc_tp->t_flags2 |= TF2_SUPPORTS_MBUFQ; rack->rack_attempt_hdwr_pace = 0; /* rxt settings */ rack->full_size_rxt = 1; rack->shape_rxt_to_pacing_min = 0; /* cmpack=1 */ rack->r_use_cmp_ack = 1; if (TCPS_HAVEESTABLISHED(rack->rc_tp->t_state) && rack->r_use_cmp_ack) rack->rc_tp->t_flags2 |= TF2_MBUF_ACKCMP; /* scwnd=1 */ rack->rack_enable_scwnd = 1; /* dynamic=100 */ rack->rc_gp_dyn_mul = 1; /* gp_inc_ca */ rack->r_ctl.rack_per_of_gp_ca = 100; /* rrr_conf=3 */ rack->r_rr_config = 3; /* npush=2 */ rack->r_ctl.rc_no_push_at_mrtt = 2; /* fillcw=1 */ if (rack->r_cwnd_was_clamped == 0) { rack->rc_pace_to_cwnd = 1; } else { rack->rc_pace_to_cwnd = 0; /* Reset all multipliers to 100.0 so just the measured bw */ rack->r_ctl.rack_per_of_gp_ss = 100; rack->r_ctl.rack_per_of_gp_ca = 100; } rack->rc_pace_fill_if_rttin_range = 0; rack->rtt_limit_mul = 0; /* noprr=1 */ rack->rack_no_prr = 1; /* lscwnd=1 */ rack->r_limit_scw = 1; /* gp_inc_rec */ rack->r_ctl.rack_per_of_gp_rec = 90; rack_client_buffer_level_set(rack); return (0); } static int rack_set_profile(struct tcp_rack *rack, int prof) { int err = EINVAL; if (prof == 1) { /* * Profile 1 is "standard" DGP. It ignores * client buffer level. */ rack->r_ctl.rc_dgp_bl_agg = DGP_LEVEL0; err = rack_set_dgp(rack); if (err) return (err); } else if (prof == 2) { /* * Profile 2 is DGP. Less aggressive with * respect to client buffer level. */ rack->r_ctl.rc_dgp_bl_agg = DGP_LEVEL1; err = rack_set_dgp(rack); if (err) return (err); } else if (prof == 3) { /* * Profile 3 is DGP. Even Less aggressive with * respect to client buffer level. */ rack->r_ctl.rc_dgp_bl_agg = DGP_LEVEL2; err = rack_set_dgp(rack); if (err) return (err); } else if (prof == 4) { /* * Profile 4 is DGP with the most responsiveness * to client buffer level. */ rack->r_ctl.rc_dgp_bl_agg = DGP_LEVEL3; err = rack_set_dgp(rack); if (err) return (err); } else if (prof == 5) { err = rack_set_dgp(rack); if (err) return (err); /* * By turning DGP off we change the rate * picked to be only the one the cwnd and rtt * get us. */ rack->dgp_on = 0; } else if (prof == 6) { err = rack_set_dgp(rack); if (err) return (err); /* * Profile 6 tweaks DGP so that it will apply to * fill-cw the same settings that profile5 does * to replace DGP. It gets then the max(dgp-rate, fillcw(discounted). */ rack->rc_fillcw_apply_discount = 1; } else if (prof == 0) { /* This changes things back to the default settings */ rack->dgp_on = 0; rack->rc_hybrid_mode = 0; err = 0; if (rack_fill_cw_state) rack->rc_pace_to_cwnd = 1; else rack->rc_pace_to_cwnd = 0; if (rack->rc_always_pace) { tcp_decrement_paced_conn(); rack_undo_cc_pacing(rack); rack->rc_always_pace = 0; } if (rack_pace_every_seg && tcp_can_enable_pacing()) { rack->rc_always_pace = 1; if (rack->rack_hibeta) rack_set_cc_pacing(rack); } else rack->rc_always_pace = 0; if (rack_dsack_std_based & 0x1) { /* Basically this means all rack timers are at least (srtt + 1/4 srtt) */ rack->rc_rack_tmr_std_based = 1; } if (rack_dsack_std_based & 0x2) { /* Basically this means rack timers are extended based on dsack by up to (2 * srtt) */ rack->rc_rack_use_dsack = 1; } if (rack_use_cmp_acks) rack->r_use_cmp_ack = 1; else rack->r_use_cmp_ack = 0; if (rack_disable_prr) rack->rack_no_prr = 1; else rack->rack_no_prr = 0; if (rack_gp_no_rec_chg) rack->rc_gp_no_rec_chg = 1; else rack->rc_gp_no_rec_chg = 0; if (rack_enable_mqueue_for_nonpaced || rack->r_use_cmp_ack) { rack->r_mbuf_queue = 1; if (TCPS_HAVEESTABLISHED(rack->rc_tp->t_state)) rack->rc_tp->t_flags2 |= TF2_MBUF_ACKCMP; rack->rc_tp->t_flags2 |= TF2_SUPPORTS_MBUFQ; } else { rack->r_mbuf_queue = 0; rack->rc_tp->t_flags2 &= ~TF2_SUPPORTS_MBUFQ; } if (rack_enable_shared_cwnd) rack->rack_enable_scwnd = 1; else rack->rack_enable_scwnd = 0; if (rack_do_dyn_mul) { /* When dynamic adjustment is on CA needs to start at 100% */ rack->rc_gp_dyn_mul = 1; if (rack_do_dyn_mul >= 100) rack->r_ctl.rack_per_of_gp_ca = rack_do_dyn_mul; } else { rack->r_ctl.rack_per_of_gp_ca = rack_per_of_gp_ca; rack->rc_gp_dyn_mul = 0; } rack->r_rr_config = 0; rack->r_ctl.rc_no_push_at_mrtt = 0; rack->rc_pace_to_cwnd = 0; rack->rc_pace_fill_if_rttin_range = 0; rack->rtt_limit_mul = 0; if (rack_enable_hw_pacing) rack->rack_hdw_pace_ena = 1; else rack->rack_hdw_pace_ena = 0; if (rack_disable_prr) rack->rack_no_prr = 1; else rack->rack_no_prr = 0; if (rack_limits_scwnd) rack->r_limit_scw = 1; else rack->r_limit_scw = 0; rack_init_retransmit_value(rack, rack_rxt_controls); err = 0; } return (err); } static int rack_add_deferred_option(struct tcp_rack *rack, int sopt_name, uint64_t loptval) { struct deferred_opt_list *dol; dol = malloc(sizeof(struct deferred_opt_list), M_TCPFSB, M_NOWAIT|M_ZERO); if (dol == NULL) { /* * No space yikes -- fail out.. */ return (0); } dol->optname = sopt_name; dol->optval = loptval; TAILQ_INSERT_TAIL(&rack->r_ctl.opt_list, dol, next); return (1); } static int process_hybrid_pacing(struct tcp_rack *rack, struct tcp_hybrid_req *hybrid) { #ifdef TCP_REQUEST_TRK struct tcp_sendfile_track *sft; struct timeval tv; tcp_seq seq; int err; microuptime(&tv); /* * If BB logging is not on we need to look at the DTL flag. * If its on already then those reasons override the DTL input. * We do this with any request, you can turn DTL on, but it does * not turn off at least from hybrid pacing requests. */ if (tcp_bblogging_on(rack->rc_tp) == 0) { if (hybrid->hybrid_flags & TCP_HYBRID_PACING_DTL) { /* Turn on BB point logging */ tcp_set_bblog_state(rack->rc_tp, TCP_LOG_VIA_BBPOINTS, TCP_BBPOINT_REQ_LEVEL_LOGGING); } } /* Make sure no fixed rate is on */ rack->use_fixed_rate = 0; rack->r_ctl.rc_fixed_pacing_rate_rec = 0; rack->r_ctl.rc_fixed_pacing_rate_ca = 0; rack->r_ctl.rc_fixed_pacing_rate_ss = 0; /* Now allocate or find our entry that will have these settings */ sft = tcp_req_alloc_req_full(rack->rc_tp, &hybrid->req, tcp_tv_to_lusectick(&tv), 0); if (sft == NULL) { rack->rc_tp->tcp_hybrid_error++; /* no space, where would it have gone? */ seq = rack->rc_tp->snd_una + rack->rc_tp->t_inpcb.inp_socket->so_snd.sb_ccc; rack_log_hybrid(rack, seq, NULL, HYBRID_LOG_NO_ROOM, __LINE__, 0); return (ENOSPC); } /* The seq will be snd_una + everything in the buffer */ seq = sft->start_seq; if ((hybrid->hybrid_flags & TCP_HYBRID_PACING_ENABLE) == 0) { /* Disabling hybrid pacing */ if (rack->rc_hybrid_mode) { rack_set_profile(rack, 0); rack->rc_tp->tcp_hybrid_stop++; } rack_log_hybrid(rack, seq, sft, HYBRID_LOG_TURNED_OFF, __LINE__, 0); return (0); } if (rack->dgp_on == 0) { /* * If we have not yet turned DGP on, do so * now setting pure DGP mode, no buffer level * response. */ if ((err = rack_set_profile(rack, 1)) != 0){ /* Failed to turn pacing on */ rack->rc_tp->tcp_hybrid_error++; rack_log_hybrid(rack, seq, sft, HYBRID_LOG_NO_PACING, __LINE__, 0); return (err); } } /* Now set in our flags */ sft->hybrid_flags = hybrid->hybrid_flags | TCP_HYBRID_PACING_WASSET; if (hybrid->hybrid_flags & TCP_HYBRID_PACING_CSPR) sft->cspr = hybrid->cspr; else sft->cspr = 0; if (hybrid->hybrid_flags & TCP_HYBRID_PACING_H_MS) sft->hint_maxseg = hybrid->hint_maxseg; else sft->hint_maxseg = 0; rack->rc_hybrid_mode = 1; rack->rc_tp->tcp_hybrid_start++; rack_log_hybrid(rack, seq, sft, HYBRID_LOG_RULES_SET, __LINE__,0); return (0); #else return (ENOTSUP); #endif } static int rack_process_option(struct tcpcb *tp, struct tcp_rack *rack, int sopt_name, uint32_t optval, uint64_t loptval, struct tcp_hybrid_req *hybrid) { struct epoch_tracker et; struct sockopt sopt; struct cc_newreno_opts opt; uint64_t val; int error = 0; uint16_t ca, ss; switch (sopt_name) { case TCP_RACK_SET_RXT_OPTIONS: if ((optval >= 0) && (optval <= 2)) { rack_init_retransmit_value(rack, optval); } else { /* * You must send in 0, 1 or 2 all else is * invalid. */ error = EINVAL; } break; case TCP_RACK_DSACK_OPT: RACK_OPTS_INC(tcp_rack_dsack_opt); if (optval & 0x1) { rack->rc_rack_tmr_std_based = 1; } else { rack->rc_rack_tmr_std_based = 0; } if (optval & 0x2) { rack->rc_rack_use_dsack = 1; } else { rack->rc_rack_use_dsack = 0; } rack_log_dsack_event(rack, 5, __LINE__, 0, 0); break; case TCP_RACK_PACING_DIVISOR: RACK_OPTS_INC(tcp_rack_pacing_divisor); if (optval == 0) { rack->r_ctl.pace_len_divisor = rack_default_pacing_divisor; } else { if (optval < RL_MIN_DIVISOR) rack->r_ctl.pace_len_divisor = RL_MIN_DIVISOR; else rack->r_ctl.pace_len_divisor = optval; } break; case TCP_RACK_HI_BETA: RACK_OPTS_INC(tcp_rack_hi_beta); if (optval > 0) { rack->rack_hibeta = 1; if ((optval >= 50) && (optval <= 100)) { /* * User wants to set a custom beta. */ rack->r_ctl.saved_hibeta = optval; if (rack->rc_pacing_cc_set) rack_undo_cc_pacing(rack); rack->r_ctl.rc_saved_beta.beta = optval; } if (rack->rc_pacing_cc_set == 0) rack_set_cc_pacing(rack); } else { rack->rack_hibeta = 0; if (rack->rc_pacing_cc_set) rack_undo_cc_pacing(rack); } break; case TCP_RACK_PACING_BETA: RACK_OPTS_INC(tcp_rack_beta); if (strcmp(tp->t_cc->name, CCALGONAME_NEWRENO) != 0) { /* This only works for newreno. */ error = EINVAL; break; } if (rack->rc_pacing_cc_set) { /* * Set them into the real CC module * whats in the rack pcb is the old values * to be used on restoral/ */ sopt.sopt_dir = SOPT_SET; opt.name = CC_NEWRENO_BETA; opt.val = optval; if (CC_ALGO(tp)->ctl_output != NULL) error = CC_ALGO(tp)->ctl_output(&tp->t_ccv, &sopt, &opt); else { error = ENOENT; break; } } else { /* * Not pacing yet so set it into our local * rack pcb storage. */ rack->r_ctl.rc_saved_beta.beta = optval; } break; case TCP_RACK_TIMER_SLOP: RACK_OPTS_INC(tcp_rack_timer_slop); rack->r_ctl.timer_slop = optval; if (rack->rc_tp->t_srtt) { /* * If we have an SRTT lets update t_rxtcur * to have the new slop. */ RACK_TCPT_RANGESET(tp->t_rxtcur, RACK_REXMTVAL(tp), rack_rto_min, rack_rto_max, rack->r_ctl.timer_slop); } break; case TCP_RACK_PACING_BETA_ECN: RACK_OPTS_INC(tcp_rack_beta_ecn); if (strcmp(tp->t_cc->name, CCALGONAME_NEWRENO) != 0) { /* This only works for newreno. */ error = EINVAL; break; } if (rack->rc_pacing_cc_set) { /* * Set them into the real CC module * whats in the rack pcb is the old values * to be used on restoral/ */ sopt.sopt_dir = SOPT_SET; opt.name = CC_NEWRENO_BETA_ECN; opt.val = optval; if (CC_ALGO(tp)->ctl_output != NULL) error = CC_ALGO(tp)->ctl_output(&tp->t_ccv, &sopt, &opt); else error = ENOENT; } else { /* * Not pacing yet so set it into our local * rack pcb storage. */ rack->r_ctl.rc_saved_beta.beta_ecn = optval; rack->r_ctl.rc_saved_beta.newreno_flags = CC_NEWRENO_BETA_ECN_ENABLED; } break; case TCP_DEFER_OPTIONS: RACK_OPTS_INC(tcp_defer_opt); if (optval) { if (rack->gp_ready) { /* Too late */ error = EINVAL; break; } rack->defer_options = 1; } else rack->defer_options = 0; break; case TCP_RACK_MEASURE_CNT: RACK_OPTS_INC(tcp_rack_measure_cnt); if (optval && (optval <= 0xff)) { rack->r_ctl.req_measurements = optval; } else error = EINVAL; break; case TCP_REC_ABC_VAL: RACK_OPTS_INC(tcp_rec_abc_val); if (optval > 0) rack->r_use_labc_for_rec = 1; else rack->r_use_labc_for_rec = 0; break; case TCP_RACK_ABC_VAL: RACK_OPTS_INC(tcp_rack_abc_val); if ((optval > 0) && (optval < 255)) rack->rc_labc = optval; else error = EINVAL; break; case TCP_HDWR_UP_ONLY: RACK_OPTS_INC(tcp_pacing_up_only); if (optval) rack->r_up_only = 1; else rack->r_up_only = 0; break; case TCP_PACING_RATE_CAP: RACK_OPTS_INC(tcp_pacing_rate_cap); rack->r_ctl.bw_rate_cap = loptval; break; case TCP_HYBRID_PACING: if (hybrid == NULL) { error = EINVAL; break; } error = process_hybrid_pacing(rack, hybrid); break; case TCP_RACK_PROFILE: RACK_OPTS_INC(tcp_profile); error = rack_set_profile(rack, optval); break; case TCP_USE_CMP_ACKS: RACK_OPTS_INC(tcp_use_cmp_acks); if ((optval == 0) && (tp->t_flags2 & TF2_MBUF_ACKCMP)) { /* You can't turn it off once its on! */ error = EINVAL; } else if ((optval == 1) && (rack->r_use_cmp_ack == 0)) { rack->r_use_cmp_ack = 1; rack->r_mbuf_queue = 1; tp->t_flags2 |= TF2_SUPPORTS_MBUFQ; } if (rack->r_use_cmp_ack && TCPS_HAVEESTABLISHED(tp->t_state)) tp->t_flags2 |= TF2_MBUF_ACKCMP; break; case TCP_SHARED_CWND_TIME_LIMIT: RACK_OPTS_INC(tcp_lscwnd); if (optval) rack->r_limit_scw = 1; else rack->r_limit_scw = 0; break; case TCP_RACK_DGP_IN_REC: RACK_OPTS_INC(tcp_dgp_in_rec); if (optval) rack->r_ctl.full_dgp_in_rec = 1; else rack->r_ctl.full_dgp_in_rec = 0; break; case TCP_RXT_CLAMP: RACK_OPTS_INC(tcp_rxt_clamp); rack_translate_clamp_value(rack, optval); break; case TCP_RACK_PACE_TO_FILL: RACK_OPTS_INC(tcp_fillcw); if (optval == 0) rack->rc_pace_to_cwnd = 0; else { rack->rc_pace_to_cwnd = 1; if (optval > 1) rack->r_fill_less_agg = 1; } if ((optval >= rack_gp_rtt_maxmul) && rack_gp_rtt_maxmul && (optval < 0xf)) { rack->rc_pace_fill_if_rttin_range = 1; rack->rtt_limit_mul = optval; } else { rack->rc_pace_fill_if_rttin_range = 0; rack->rtt_limit_mul = 0; } break; case TCP_RACK_NO_PUSH_AT_MAX: RACK_OPTS_INC(tcp_npush); if (optval == 0) rack->r_ctl.rc_no_push_at_mrtt = 0; else if (optval < 0xff) rack->r_ctl.rc_no_push_at_mrtt = optval; else error = EINVAL; break; case TCP_SHARED_CWND_ENABLE: RACK_OPTS_INC(tcp_rack_scwnd); if (optval == 0) rack->rack_enable_scwnd = 0; else rack->rack_enable_scwnd = 1; break; case TCP_RACK_MBUF_QUEUE: /* Now do we use the LRO mbuf-queue feature */ RACK_OPTS_INC(tcp_rack_mbufq); if (optval || rack->r_use_cmp_ack) rack->r_mbuf_queue = 1; else rack->r_mbuf_queue = 0; if (rack->r_mbuf_queue || rack->rc_always_pace || rack->r_use_cmp_ack) tp->t_flags2 |= TF2_SUPPORTS_MBUFQ; else tp->t_flags2 &= ~TF2_SUPPORTS_MBUFQ; break; case TCP_RACK_NONRXT_CFG_RATE: RACK_OPTS_INC(tcp_rack_cfg_rate); if (optval == 0) rack->rack_rec_nonrxt_use_cr = 0; else rack->rack_rec_nonrxt_use_cr = 1; break; case TCP_NO_PRR: RACK_OPTS_INC(tcp_rack_noprr); if (optval == 0) rack->rack_no_prr = 0; else if (optval == 1) rack->rack_no_prr = 1; else if (optval == 2) rack->no_prr_addback = 1; else error = EINVAL; break; case TCP_TIMELY_DYN_ADJ: RACK_OPTS_INC(tcp_timely_dyn); if (optval == 0) rack->rc_gp_dyn_mul = 0; else { rack->rc_gp_dyn_mul = 1; if (optval >= 100) { /* * If the user sets something 100 or more * its the gp_ca value. */ rack->r_ctl.rack_per_of_gp_ca = optval; } } break; case TCP_RACK_DO_DETECTION: RACK_OPTS_INC(tcp_rack_do_detection); if (optval == 0) rack->do_detection = 0; else rack->do_detection = 1; break; case TCP_RACK_TLP_USE: if ((optval < TLP_USE_ID) || (optval > TLP_USE_TWO_TWO)) { error = EINVAL; break; } RACK_OPTS_INC(tcp_tlp_use); rack->rack_tlp_threshold_use = optval; break; case TCP_RACK_TLP_REDUCE: /* RACK TLP cwnd reduction (bool) */ RACK_OPTS_INC(tcp_rack_tlp_reduce); rack->r_ctl.rc_tlp_cwnd_reduce = optval; break; /* Pacing related ones */ case TCP_RACK_PACE_ALWAYS: /* * zero is old rack method, 1 is new * method using a pacing rate. */ RACK_OPTS_INC(tcp_rack_pace_always); if (optval > 0) { if (rack->rc_always_pace) { error = EALREADY; break; } else if (tcp_can_enable_pacing()) { rack->rc_always_pace = 1; if (rack->rack_hibeta) rack_set_cc_pacing(rack); } else { error = ENOSPC; break; } } else { if (rack->rc_always_pace) { tcp_decrement_paced_conn(); rack->rc_always_pace = 0; rack_undo_cc_pacing(rack); } } if (rack->r_mbuf_queue || rack->rc_always_pace || rack->r_use_cmp_ack) tp->t_flags2 |= TF2_SUPPORTS_MBUFQ; else tp->t_flags2 &= ~TF2_SUPPORTS_MBUFQ; /* A rate may be set irate or other, if so set seg size */ rack_update_seg(rack); break; case TCP_BBR_RACK_INIT_RATE: RACK_OPTS_INC(tcp_initial_rate); val = optval; /* Change from kbits per second to bytes per second */ val *= 1000; val /= 8; rack->r_ctl.init_rate = val; if (rack->rc_init_win != rack_default_init_window) { uint32_t win, snt; /* * Options don't always get applied * in the order you think. So in order * to assure we update a cwnd we need * to check and see if we are still * where we should raise the cwnd. */ win = rc_init_window(rack); if (SEQ_GT(tp->snd_max, tp->iss)) snt = tp->snd_max - tp->iss; else snt = 0; if ((snt < win) && (tp->snd_cwnd < win)) tp->snd_cwnd = win; } if (rack->rc_always_pace) rack_update_seg(rack); break; case TCP_BBR_IWINTSO: RACK_OPTS_INC(tcp_initial_win); if (optval && (optval <= 0xff)) { uint32_t win, snt; rack->rc_init_win = optval; win = rc_init_window(rack); if (SEQ_GT(tp->snd_max, tp->iss)) snt = tp->snd_max - tp->iss; else snt = 0; if ((snt < win) && (tp->t_srtt | rack->r_ctl.init_rate)) { /* * We are not past the initial window * and we have some bases for pacing, * so we need to possibly adjust up * the cwnd. Note even if we don't set * the cwnd, its still ok to raise the rc_init_win * which can be used coming out of idle when we * would have a rate. */ if (tp->snd_cwnd < win) tp->snd_cwnd = win; } if (rack->rc_always_pace) rack_update_seg(rack); } else error = EINVAL; break; case TCP_RACK_FORCE_MSEG: RACK_OPTS_INC(tcp_rack_force_max_seg); if (optval) rack->rc_force_max_seg = 1; else rack->rc_force_max_seg = 0; break; case TCP_RACK_PACE_MIN_SEG: RACK_OPTS_INC(tcp_rack_min_seg); rack->r_ctl.rc_user_set_min_segs = (0x0000ffff & optval); rack_set_pace_segments(tp, rack, __LINE__, NULL); break; case TCP_RACK_PACE_MAX_SEG: /* Max segments size in a pace in bytes */ RACK_OPTS_INC(tcp_rack_max_seg); if (optval <= MAX_USER_SET_SEG) rack->rc_user_set_max_segs = optval; else rack->rc_user_set_max_segs = MAX_USER_SET_SEG; rack_set_pace_segments(tp, rack, __LINE__, NULL); break; case TCP_RACK_PACE_RATE_REC: /* Set the fixed pacing rate in Bytes per second ca */ RACK_OPTS_INC(tcp_rack_pace_rate_rec); rack->r_ctl.rc_fixed_pacing_rate_rec = optval; if (rack->r_ctl.rc_fixed_pacing_rate_ca == 0) rack->r_ctl.rc_fixed_pacing_rate_ca = optval; if (rack->r_ctl.rc_fixed_pacing_rate_ss == 0) rack->r_ctl.rc_fixed_pacing_rate_ss = optval; rack->use_fixed_rate = 1; if (rack->rack_hibeta) rack_set_cc_pacing(rack); rack_log_pacing_delay_calc(rack, rack->r_ctl.rc_fixed_pacing_rate_ss, rack->r_ctl.rc_fixed_pacing_rate_ca, rack->r_ctl.rc_fixed_pacing_rate_rec, 0, 0, 8, __LINE__, NULL,0); break; case TCP_RACK_PACE_RATE_SS: /* Set the fixed pacing rate in Bytes per second ca */ RACK_OPTS_INC(tcp_rack_pace_rate_ss); rack->r_ctl.rc_fixed_pacing_rate_ss = optval; if (rack->r_ctl.rc_fixed_pacing_rate_ca == 0) rack->r_ctl.rc_fixed_pacing_rate_ca = optval; if (rack->r_ctl.rc_fixed_pacing_rate_rec == 0) rack->r_ctl.rc_fixed_pacing_rate_rec = optval; rack->use_fixed_rate = 1; if (rack->rack_hibeta) rack_set_cc_pacing(rack); rack_log_pacing_delay_calc(rack, rack->r_ctl.rc_fixed_pacing_rate_ss, rack->r_ctl.rc_fixed_pacing_rate_ca, rack->r_ctl.rc_fixed_pacing_rate_rec, 0, 0, 8, __LINE__, NULL, 0); break; case TCP_RACK_PACE_RATE_CA: /* Set the fixed pacing rate in Bytes per second ca */ RACK_OPTS_INC(tcp_rack_pace_rate_ca); rack->r_ctl.rc_fixed_pacing_rate_ca = optval; if (rack->r_ctl.rc_fixed_pacing_rate_ss == 0) rack->r_ctl.rc_fixed_pacing_rate_ss = optval; if (rack->r_ctl.rc_fixed_pacing_rate_rec == 0) rack->r_ctl.rc_fixed_pacing_rate_rec = optval; rack->use_fixed_rate = 1; if (rack->rack_hibeta) rack_set_cc_pacing(rack); rack_log_pacing_delay_calc(rack, rack->r_ctl.rc_fixed_pacing_rate_ss, rack->r_ctl.rc_fixed_pacing_rate_ca, rack->r_ctl.rc_fixed_pacing_rate_rec, 0, 0, 8, __LINE__, NULL, 0); break; case TCP_RACK_GP_INCREASE_REC: RACK_OPTS_INC(tcp_gp_inc_rec); rack->r_ctl.rack_per_of_gp_rec = optval; rack_log_pacing_delay_calc(rack, rack->r_ctl.rack_per_of_gp_ss, rack->r_ctl.rack_per_of_gp_ca, rack->r_ctl.rack_per_of_gp_rec, 0, 0, 1, __LINE__, NULL, 0); break; case TCP_RACK_GP_INCREASE_CA: RACK_OPTS_INC(tcp_gp_inc_ca); ca = optval; if (ca < 100) { /* * We don't allow any reduction * over the GP b/w. */ error = EINVAL; break; } rack->r_ctl.rack_per_of_gp_ca = ca; rack_log_pacing_delay_calc(rack, rack->r_ctl.rack_per_of_gp_ss, rack->r_ctl.rack_per_of_gp_ca, rack->r_ctl.rack_per_of_gp_rec, 0, 0, 1, __LINE__, NULL, 0); break; case TCP_RACK_GP_INCREASE_SS: RACK_OPTS_INC(tcp_gp_inc_ss); ss = optval; if (ss < 100) { /* * We don't allow any reduction * over the GP b/w. */ error = EINVAL; break; } rack->r_ctl.rack_per_of_gp_ss = ss; rack_log_pacing_delay_calc(rack, rack->r_ctl.rack_per_of_gp_ss, rack->r_ctl.rack_per_of_gp_ca, rack->r_ctl.rack_per_of_gp_rec, 0, 0, 1, __LINE__, NULL, 0); break; case TCP_RACK_RR_CONF: RACK_OPTS_INC(tcp_rack_rrr_no_conf_rate); if (optval && optval <= 3) rack->r_rr_config = optval; else rack->r_rr_config = 0; break; case TCP_PACING_DND: /* URL:dnd */ if (optval > 0) rack->rc_pace_dnd = 1; else rack->rc_pace_dnd = 0; break; case TCP_HDWR_RATE_CAP: RACK_OPTS_INC(tcp_hdwr_rate_cap); if (optval) { if (rack->r_rack_hw_rate_caps == 0) rack->r_rack_hw_rate_caps = 1; else error = EALREADY; } else { rack->r_rack_hw_rate_caps = 0; } break; case TCP_RACK_SPLIT_LIMIT: RACK_OPTS_INC(tcp_split_limit); rack->r_ctl.rc_split_limit = optval; break; case TCP_BBR_HDWR_PACE: RACK_OPTS_INC(tcp_hdwr_pacing); if (optval){ if (rack->rack_hdrw_pacing == 0) { rack->rack_hdw_pace_ena = 1; rack->rack_attempt_hdwr_pace = 0; } else error = EALREADY; } else { rack->rack_hdw_pace_ena = 0; #ifdef RATELIMIT if (rack->r_ctl.crte != NULL) { rack->rack_hdrw_pacing = 0; rack->rack_attempt_hdwr_pace = 0; tcp_rel_pacing_rate(rack->r_ctl.crte, tp); rack->r_ctl.crte = NULL; } #endif } break; /* End Pacing related ones */ case TCP_RACK_PRR_SENDALOT: /* Allow PRR to send more than one seg */ RACK_OPTS_INC(tcp_rack_prr_sendalot); rack->r_ctl.rc_prr_sendalot = optval; break; case TCP_RACK_MIN_TO: /* Minimum time between rack t-o's in ms */ RACK_OPTS_INC(tcp_rack_min_to); rack->r_ctl.rc_min_to = optval; break; case TCP_RACK_EARLY_SEG: /* If early recovery max segments */ RACK_OPTS_INC(tcp_rack_early_seg); rack->r_ctl.rc_early_recovery_segs = optval; break; case TCP_RACK_ENABLE_HYSTART: { if (optval) { tp->t_ccv.flags |= CCF_HYSTART_ALLOWED; if (rack_do_hystart > RACK_HYSTART_ON) tp->t_ccv.flags |= CCF_HYSTART_CAN_SH_CWND; if (rack_do_hystart > RACK_HYSTART_ON_W_SC) tp->t_ccv.flags |= CCF_HYSTART_CONS_SSTH; } else { tp->t_ccv.flags &= ~(CCF_HYSTART_ALLOWED|CCF_HYSTART_CAN_SH_CWND|CCF_HYSTART_CONS_SSTH); } } break; case TCP_RACK_REORD_THRESH: /* RACK reorder threshold (shift amount) */ RACK_OPTS_INC(tcp_rack_reord_thresh); if ((optval > 0) && (optval < 31)) rack->r_ctl.rc_reorder_shift = optval; else error = EINVAL; break; case TCP_RACK_REORD_FADE: /* Does reordering fade after ms time */ RACK_OPTS_INC(tcp_rack_reord_fade); rack->r_ctl.rc_reorder_fade = optval; break; case TCP_RACK_TLP_THRESH: /* RACK TLP theshold i.e. srtt+(srtt/N) */ RACK_OPTS_INC(tcp_rack_tlp_thresh); if (optval) rack->r_ctl.rc_tlp_threshold = optval; else error = EINVAL; break; case TCP_BBR_USE_RACK_RR: RACK_OPTS_INC(tcp_rack_rr); if (optval) rack->use_rack_rr = 1; else rack->use_rack_rr = 0; break; case TCP_RACK_PKT_DELAY: /* RACK added ms i.e. rack-rtt + reord + N */ RACK_OPTS_INC(tcp_rack_pkt_delay); rack->r_ctl.rc_pkt_delay = optval; break; case TCP_DELACK: RACK_OPTS_INC(tcp_rack_delayed_ack); if (optval == 0) tp->t_delayed_ack = 0; else tp->t_delayed_ack = 1; if (tp->t_flags & TF_DELACK) { tp->t_flags &= ~TF_DELACK; tp->t_flags |= TF_ACKNOW; NET_EPOCH_ENTER(et); rack_output(tp); NET_EPOCH_EXIT(et); } break; case TCP_BBR_RACK_RTT_USE: RACK_OPTS_INC(tcp_rack_rtt_use); if ((optval != USE_RTT_HIGH) && (optval != USE_RTT_LOW) && (optval != USE_RTT_AVG)) error = EINVAL; else rack->r_ctl.rc_rate_sample_method = optval; break; case TCP_DATA_AFTER_CLOSE: RACK_OPTS_INC(tcp_data_after_close); if (optval) rack->rc_allow_data_af_clo = 1; else rack->rc_allow_data_af_clo = 0; break; default: break; } tcp_log_socket_option(tp, sopt_name, optval, error); return (error); } static void rack_apply_deferred_options(struct tcp_rack *rack) { struct deferred_opt_list *dol, *sdol; uint32_t s_optval; TAILQ_FOREACH_SAFE(dol, &rack->r_ctl.opt_list, next, sdol) { TAILQ_REMOVE(&rack->r_ctl.opt_list, dol, next); /* Disadvantage of deferal is you loose the error return */ s_optval = (uint32_t)dol->optval; (void)rack_process_option(rack->rc_tp, rack, dol->optname, s_optval, dol->optval, NULL); free(dol, M_TCPDO); } } static void rack_hw_tls_change(struct tcpcb *tp, int chg) { /* Update HW tls state */ struct tcp_rack *rack; rack = (struct tcp_rack *)tp->t_fb_ptr; if (chg) rack->r_ctl.fsb.hw_tls = 1; else rack->r_ctl.fsb.hw_tls = 0; } static int rack_pru_options(struct tcpcb *tp, int flags) { if (flags & PRUS_OOB) return (EOPNOTSUPP); return (0); } static bool rack_wake_check(struct tcpcb *tp) { struct tcp_rack *rack; struct timeval tv; uint32_t cts; rack = (struct tcp_rack *)tp->t_fb_ptr; if (rack->r_ctl.rc_hpts_flags) { cts = tcp_get_usecs(&tv); if ((rack->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) == PACE_PKT_OUTPUT){ /* * Pacing timer is up, check if we are ready. */ if (TSTMP_GEQ(cts, rack->r_ctl.rc_last_output_to)) return (true); } else if ((rack->r_ctl.rc_hpts_flags & PACE_TMR_MASK) != 0) { /* * A timer is up, check if we are ready. */ if (TSTMP_GEQ(cts, rack->r_ctl.rc_timer_exp)) return (true); } } return (false); } static struct tcp_function_block __tcp_rack = { .tfb_tcp_block_name = __XSTRING(STACKNAME), .tfb_tcp_output = rack_output, .tfb_do_queued_segments = ctf_do_queued_segments, .tfb_do_segment_nounlock = rack_do_segment_nounlock, .tfb_tcp_do_segment = rack_do_segment, .tfb_tcp_ctloutput = rack_ctloutput, .tfb_tcp_fb_init = rack_init, .tfb_tcp_fb_fini = rack_fini, .tfb_tcp_timer_stop_all = rack_stopall, .tfb_tcp_rexmit_tmr = rack_remxt_tmr, .tfb_tcp_handoff_ok = rack_handoff_ok, .tfb_tcp_mtu_chg = rack_mtu_change, .tfb_pru_options = rack_pru_options, .tfb_hwtls_change = rack_hw_tls_change, .tfb_chg_query = rack_chg_query, .tfb_switch_failed = rack_switch_failed, .tfb_early_wake_check = rack_wake_check, .tfb_compute_pipe = rack_compute_pipe, .tfb_flags = TCP_FUNC_OUTPUT_CANDROP, }; /* * rack_ctloutput() must drop the inpcb lock before performing copyin on * socket option arguments. When it re-acquires the lock after the copy, it * has to revalidate that the connection is still valid for the socket * option. */ static int rack_set_sockopt(struct tcpcb *tp, struct sockopt *sopt) { struct inpcb *inp = tptoinpcb(tp); #ifdef INET struct ip *ip; #endif struct tcp_rack *rack; struct tcp_hybrid_req hybrid; uint64_t loptval; int32_t error = 0, optval; rack = (struct tcp_rack *)tp->t_fb_ptr; if (rack == NULL) { INP_WUNLOCK(inp); return (EINVAL); } #ifdef INET ip = (struct ip *)rack->r_ctl.fsb.tcp_ip_hdr; #endif switch (sopt->sopt_level) { #ifdef INET6 case IPPROTO_IPV6: MPASS(inp->inp_vflag & INP_IPV6PROTO); switch (sopt->sopt_name) { case IPV6_USE_MIN_MTU: tcp6_use_min_mtu(tp); break; } INP_WUNLOCK(inp); return (0); #endif #ifdef INET case IPPROTO_IP: switch (sopt->sopt_name) { case IP_TOS: /* * The DSCP codepoint has changed, update the fsb. */ ip->ip_tos = rack->rc_inp->inp_ip_tos; break; case IP_TTL: /* * The TTL has changed, update the fsb. */ ip->ip_ttl = rack->rc_inp->inp_ip_ttl; break; } INP_WUNLOCK(inp); return (0); #endif #ifdef SO_PEERPRIO case SOL_SOCKET: switch (sopt->sopt_name) { case SO_PEERPRIO: /* SC-URL:bs */ /* Already read in and sanity checked in sosetopt(). */ if (inp->inp_socket) { rack->client_bufferlvl = inp->inp_socket->so_peerprio; rack_client_buffer_level_set(rack); } break; } INP_WUNLOCK(inp); return (0); #endif case IPPROTO_TCP: switch (sopt->sopt_name) { case TCP_RACK_TLP_REDUCE: /* URL:tlp_reduce */ /* Pacing related ones */ case TCP_RACK_PACE_ALWAYS: /* URL:pace_always */ case TCP_BBR_RACK_INIT_RATE: /* URL:irate */ case TCP_BBR_IWINTSO: /* URL:tso_iwin */ case TCP_RACK_PACE_MIN_SEG: /* URL:pace_min_seg */ case TCP_RACK_PACE_MAX_SEG: /* URL:pace_max_seg */ case TCP_RACK_FORCE_MSEG: /* URL:force_max_seg */ case TCP_RACK_PACE_RATE_CA: /* URL:pr_ca */ case TCP_RACK_PACE_RATE_SS: /* URL:pr_ss*/ case TCP_RACK_PACE_RATE_REC: /* URL:pr_rec */ case TCP_RACK_GP_INCREASE_CA: /* URL:gp_inc_ca */ case TCP_RACK_GP_INCREASE_SS: /* URL:gp_inc_ss */ case TCP_RACK_GP_INCREASE_REC: /* URL:gp_inc_rec */ case TCP_RACK_RR_CONF: /* URL:rrr_conf */ case TCP_BBR_HDWR_PACE: /* URL:hdwrpace */ case TCP_HDWR_RATE_CAP: /* URL:hdwrcap boolean */ case TCP_PACING_RATE_CAP: /* URL:cap -- used by side-channel */ case TCP_HDWR_UP_ONLY: /* URL:uponly -- hardware pacing boolean */ case TCP_RACK_PACING_BETA: /* URL:pacing_beta */ case TCP_RACK_PACING_BETA_ECN: /* URL:pacing_beta_ecn */ case TCP_RACK_PACE_TO_FILL: /* URL:fillcw */ case TCP_RACK_DGP_IN_REC: /* URL:dgpinrec */ /* End pacing related */ case TCP_RXT_CLAMP: /* URL:rxtclamp */ case TCP_DELACK: /* URL:delack (in base TCP i.e. tcp_hints along with cc etc ) */ case TCP_RACK_PRR_SENDALOT: /* URL:prr_sendalot */ case TCP_RACK_MIN_TO: /* URL:min_to */ case TCP_RACK_EARLY_SEG: /* URL:early_seg */ case TCP_RACK_REORD_THRESH: /* URL:reord_thresh */ case TCP_RACK_REORD_FADE: /* URL:reord_fade */ case TCP_RACK_TLP_THRESH: /* URL:tlp_thresh */ case TCP_RACK_PKT_DELAY: /* URL:pkt_delay */ case TCP_RACK_TLP_USE: /* URL:tlp_use */ case TCP_BBR_RACK_RTT_USE: /* URL:rttuse */ case TCP_BBR_USE_RACK_RR: /* URL:rackrr */ case TCP_RACK_DO_DETECTION: /* URL:detect */ case TCP_NO_PRR: /* URL:noprr */ case TCP_TIMELY_DYN_ADJ: /* URL:dynamic */ case TCP_DATA_AFTER_CLOSE: /* no URL */ case TCP_RACK_NONRXT_CFG_RATE: /* URL:nonrxtcr */ case TCP_SHARED_CWND_ENABLE: /* URL:scwnd */ case TCP_RACK_MBUF_QUEUE: /* URL:mqueue */ case TCP_RACK_NO_PUSH_AT_MAX: /* URL:npush */ case TCP_SHARED_CWND_TIME_LIMIT: /* URL:lscwnd */ case TCP_RACK_PROFILE: /* URL:profile */ case TCP_HYBRID_PACING: /* URL:hybrid */ case TCP_USE_CMP_ACKS: /* URL:cmpack */ case TCP_RACK_ABC_VAL: /* URL:labc */ case TCP_REC_ABC_VAL: /* URL:reclabc */ case TCP_RACK_MEASURE_CNT: /* URL:measurecnt */ case TCP_DEFER_OPTIONS: /* URL:defer */ case TCP_RACK_DSACK_OPT: /* URL:dsack */ case TCP_RACK_TIMER_SLOP: /* URL:timer_slop */ case TCP_RACK_ENABLE_HYSTART: /* URL:hystart */ case TCP_RACK_SET_RXT_OPTIONS: /* URL:rxtsz */ case TCP_RACK_HI_BETA: /* URL:hibeta */ case TCP_RACK_SPLIT_LIMIT: /* URL:split */ case TCP_RACK_PACING_DIVISOR: /* URL:divisor */ case TCP_PACING_DND: /* URL:dnd */ goto process_opt; break; default: /* Filter off all unknown options to the base stack */ return (tcp_default_ctloutput(tp, sopt)); break; } default: INP_WUNLOCK(inp); return (0); } process_opt: INP_WUNLOCK(inp); if (sopt->sopt_name == TCP_PACING_RATE_CAP) { error = sooptcopyin(sopt, &loptval, sizeof(loptval), sizeof(loptval)); /* * We truncate it down to 32 bits for the socket-option trace this * means rates > 34Gbps won't show right, but thats probably ok. */ optval = (uint32_t)loptval; } else if (sopt->sopt_name == TCP_HYBRID_PACING) { error = sooptcopyin(sopt, &hybrid, sizeof(hybrid), sizeof(hybrid)); } else { error = sooptcopyin(sopt, &optval, sizeof(optval), sizeof(optval)); /* Save it in 64 bit form too */ loptval = optval; } if (error) return (error); INP_WLOCK(inp); if (tp->t_fb != &__tcp_rack) { INP_WUNLOCK(inp); return (ENOPROTOOPT); } if (rack->defer_options && (rack->gp_ready == 0) && (sopt->sopt_name != TCP_DEFER_OPTIONS) && (sopt->sopt_name != TCP_HYBRID_PACING) && (sopt->sopt_name != TCP_RACK_PACING_BETA) && (sopt->sopt_name != TCP_RACK_SET_RXT_OPTIONS) && (sopt->sopt_name != TCP_RACK_PACING_BETA_ECN) && (sopt->sopt_name != TCP_RACK_MEASURE_CNT)) { /* Options are beind deferred */ if (rack_add_deferred_option(rack, sopt->sopt_name, loptval)) { INP_WUNLOCK(inp); return (0); } else { /* No memory to defer, fail */ INP_WUNLOCK(inp); return (ENOMEM); } } error = rack_process_option(tp, rack, sopt->sopt_name, optval, loptval, &hybrid); INP_WUNLOCK(inp); return (error); } static void rack_fill_info(struct tcpcb *tp, struct tcp_info *ti) { INP_WLOCK_ASSERT(tptoinpcb(tp)); bzero(ti, sizeof(*ti)); ti->tcpi_state = tp->t_state; if ((tp->t_flags & TF_REQ_TSTMP) && (tp->t_flags & TF_RCVD_TSTMP)) ti->tcpi_options |= TCPI_OPT_TIMESTAMPS; if (tp->t_flags & TF_SACK_PERMIT) ti->tcpi_options |= TCPI_OPT_SACK; if ((tp->t_flags & TF_REQ_SCALE) && (tp->t_flags & TF_RCVD_SCALE)) { ti->tcpi_options |= TCPI_OPT_WSCALE; ti->tcpi_snd_wscale = tp->snd_scale; ti->tcpi_rcv_wscale = tp->rcv_scale; } if (tp->t_flags2 & (TF2_ECN_PERMIT | TF2_ACE_PERMIT)) ti->tcpi_options |= TCPI_OPT_ECN; if (tp->t_flags & TF_FASTOPEN) ti->tcpi_options |= TCPI_OPT_TFO; /* still kept in ticks is t_rcvtime */ ti->tcpi_last_data_recv = ((uint32_t)ticks - tp->t_rcvtime) * tick; /* Since we hold everything in precise useconds this is easy */ ti->tcpi_rtt = tp->t_srtt; ti->tcpi_rttvar = tp->t_rttvar; ti->tcpi_rto = tp->t_rxtcur; ti->tcpi_snd_ssthresh = tp->snd_ssthresh; ti->tcpi_snd_cwnd = tp->snd_cwnd; /* * FreeBSD-specific extension fields for tcp_info. */ ti->tcpi_rcv_space = tp->rcv_wnd; ti->tcpi_rcv_nxt = tp->rcv_nxt; ti->tcpi_snd_wnd = tp->snd_wnd; ti->tcpi_snd_bwnd = 0; /* Unused, kept for compat. */ ti->tcpi_snd_nxt = tp->snd_nxt; ti->tcpi_snd_mss = tp->t_maxseg; ti->tcpi_rcv_mss = tp->t_maxseg; ti->tcpi_snd_rexmitpack = tp->t_sndrexmitpack; ti->tcpi_rcv_ooopack = tp->t_rcvoopack; ti->tcpi_snd_zerowin = tp->t_sndzerowin; ti->tcpi_total_tlp = tp->t_sndtlppack; ti->tcpi_total_tlp_bytes = tp->t_sndtlpbyte; #ifdef NETFLIX_STATS memcpy(&ti->tcpi_rxsyninfo, &tp->t_rxsyninfo, sizeof(struct tcpsyninfo)); #endif #ifdef TCP_OFFLOAD if (tp->t_flags & TF_TOE) { ti->tcpi_options |= TCPI_OPT_TOE; tcp_offload_tcp_info(tp, ti); } #endif } static int rack_get_sockopt(struct tcpcb *tp, struct sockopt *sopt) { struct inpcb *inp = tptoinpcb(tp); struct tcp_rack *rack; int32_t error, optval; uint64_t val, loptval; struct tcp_info ti; /* * Because all our options are either boolean or an int, we can just * pull everything into optval and then unlock and copy. If we ever * add a option that is not a int, then this will have quite an * impact to this routine. */ error = 0; rack = (struct tcp_rack *)tp->t_fb_ptr; if (rack == NULL) { INP_WUNLOCK(inp); return (EINVAL); } switch (sopt->sopt_name) { case TCP_INFO: /* First get the info filled */ rack_fill_info(tp, &ti); /* Fix up the rtt related fields if needed */ INP_WUNLOCK(inp); error = sooptcopyout(sopt, &ti, sizeof ti); return (error); /* * Beta is the congestion control value for NewReno that influences how * much of a backoff happens when loss is detected. It is normally set * to 50 for 50% i.e. the cwnd is reduced to 50% of its previous value * when you exit recovery. */ case TCP_RACK_PACING_BETA: if (strcmp(tp->t_cc->name, CCALGONAME_NEWRENO) != 0) error = EINVAL; else if (rack->rc_pacing_cc_set == 0) optval = rack->r_ctl.rc_saved_beta.beta; else { /* * Reach out into the CC data and report back what * I have previously set. Yeah it looks hackish but * we don't want to report the saved values. */ if (tp->t_ccv.cc_data) optval = ((struct newreno *)tp->t_ccv.cc_data)->beta; else error = EINVAL; } break; /* * Beta_ecn is the congestion control value for NewReno that influences how * much of a backoff happens when a ECN mark is detected. It is normally set * to 80 for 80% i.e. the cwnd is reduced by 20% of its previous value when * you exit recovery. Note that classic ECN has a beta of 50, it is only * ABE Ecn that uses this "less" value, but we do too with pacing :) */ case TCP_RACK_PACING_BETA_ECN: if (strcmp(tp->t_cc->name, CCALGONAME_NEWRENO) != 0) error = EINVAL; else if (rack->rc_pacing_cc_set == 0) optval = rack->r_ctl.rc_saved_beta.beta_ecn; else { /* * Reach out into the CC data and report back what * I have previously set. Yeah it looks hackish but * we don't want to report the saved values. */ if (tp->t_ccv.cc_data) optval = ((struct newreno *)tp->t_ccv.cc_data)->beta_ecn; else error = EINVAL; } break; case TCP_RACK_DSACK_OPT: optval = 0; if (rack->rc_rack_tmr_std_based) { optval |= 1; } if (rack->rc_rack_use_dsack) { optval |= 2; } break; case TCP_RACK_ENABLE_HYSTART: { if (tp->t_ccv.flags & CCF_HYSTART_ALLOWED) { optval = RACK_HYSTART_ON; if (tp->t_ccv.flags & CCF_HYSTART_CAN_SH_CWND) optval = RACK_HYSTART_ON_W_SC; if (tp->t_ccv.flags & CCF_HYSTART_CONS_SSTH) optval = RACK_HYSTART_ON_W_SC_C; } else { optval = RACK_HYSTART_OFF; } } break; case TCP_RACK_DGP_IN_REC: optval = rack->r_ctl.full_dgp_in_rec; break; case TCP_RACK_HI_BETA: optval = rack->rack_hibeta; break; case TCP_RXT_CLAMP: optval = rack->r_ctl.saved_rxt_clamp_val; break; case TCP_DEFER_OPTIONS: optval = rack->defer_options; break; case TCP_RACK_MEASURE_CNT: optval = rack->r_ctl.req_measurements; break; case TCP_REC_ABC_VAL: optval = rack->r_use_labc_for_rec; break; case TCP_RACK_ABC_VAL: optval = rack->rc_labc; break; case TCP_HDWR_UP_ONLY: optval= rack->r_up_only; break; case TCP_PACING_RATE_CAP: loptval = rack->r_ctl.bw_rate_cap; break; case TCP_RACK_PROFILE: /* You cannot retrieve a profile, its write only */ error = EINVAL; break; case TCP_HYBRID_PACING: /* You cannot retrieve hybrid pacing information, its write only */ error = EINVAL; break; case TCP_USE_CMP_ACKS: optval = rack->r_use_cmp_ack; break; case TCP_RACK_PACE_TO_FILL: optval = rack->rc_pace_to_cwnd; if (optval && rack->r_fill_less_agg) optval++; break; case TCP_RACK_NO_PUSH_AT_MAX: optval = rack->r_ctl.rc_no_push_at_mrtt; break; case TCP_SHARED_CWND_ENABLE: optval = rack->rack_enable_scwnd; break; case TCP_RACK_NONRXT_CFG_RATE: optval = rack->rack_rec_nonrxt_use_cr; break; case TCP_NO_PRR: if (rack->rack_no_prr == 1) optval = 1; else if (rack->no_prr_addback == 1) optval = 2; else optval = 0; break; case TCP_RACK_DO_DETECTION: optval = rack->do_detection; break; case TCP_RACK_MBUF_QUEUE: /* Now do we use the LRO mbuf-queue feature */ optval = rack->r_mbuf_queue; break; case TCP_TIMELY_DYN_ADJ: optval = rack->rc_gp_dyn_mul; break; case TCP_BBR_IWINTSO: optval = rack->rc_init_win; break; case TCP_RACK_TLP_REDUCE: /* RACK TLP cwnd reduction (bool) */ optval = rack->r_ctl.rc_tlp_cwnd_reduce; break; case TCP_BBR_RACK_INIT_RATE: val = rack->r_ctl.init_rate; /* convert to kbits per sec */ val *= 8; val /= 1000; optval = (uint32_t)val; break; case TCP_RACK_FORCE_MSEG: optval = rack->rc_force_max_seg; break; case TCP_RACK_PACE_MIN_SEG: optval = rack->r_ctl.rc_user_set_min_segs; break; case TCP_RACK_PACE_MAX_SEG: /* Max segments in a pace */ optval = rack->rc_user_set_max_segs; break; case TCP_RACK_PACE_ALWAYS: /* Use the always pace method */ optval = rack->rc_always_pace; break; case TCP_RACK_PRR_SENDALOT: /* Allow PRR to send more than one seg */ optval = rack->r_ctl.rc_prr_sendalot; break; case TCP_RACK_MIN_TO: /* Minimum time between rack t-o's in ms */ optval = rack->r_ctl.rc_min_to; break; case TCP_RACK_SPLIT_LIMIT: optval = rack->r_ctl.rc_split_limit; break; case TCP_RACK_EARLY_SEG: /* If early recovery max segments */ optval = rack->r_ctl.rc_early_recovery_segs; break; case TCP_RACK_REORD_THRESH: /* RACK reorder threshold (shift amount) */ optval = rack->r_ctl.rc_reorder_shift; break; case TCP_RACK_REORD_FADE: /* Does reordering fade after ms time */ optval = rack->r_ctl.rc_reorder_fade; break; case TCP_BBR_USE_RACK_RR: /* Do we use the rack cheat for rxt */ optval = rack->use_rack_rr; break; case TCP_RACK_RR_CONF: optval = rack->r_rr_config; break; case TCP_HDWR_RATE_CAP: optval = rack->r_rack_hw_rate_caps; break; case TCP_BBR_HDWR_PACE: optval = rack->rack_hdw_pace_ena; break; case TCP_RACK_TLP_THRESH: /* RACK TLP theshold i.e. srtt+(srtt/N) */ optval = rack->r_ctl.rc_tlp_threshold; break; case TCP_RACK_PKT_DELAY: /* RACK added ms i.e. rack-rtt + reord + N */ optval = rack->r_ctl.rc_pkt_delay; break; case TCP_RACK_TLP_USE: optval = rack->rack_tlp_threshold_use; break; case TCP_PACING_DND: optval = rack->rc_pace_dnd; break; case TCP_RACK_PACE_RATE_CA: optval = rack->r_ctl.rc_fixed_pacing_rate_ca; break; case TCP_RACK_PACE_RATE_SS: optval = rack->r_ctl.rc_fixed_pacing_rate_ss; break; case TCP_RACK_PACE_RATE_REC: optval = rack->r_ctl.rc_fixed_pacing_rate_rec; break; case TCP_RACK_GP_INCREASE_SS: optval = rack->r_ctl.rack_per_of_gp_ca; break; case TCP_RACK_GP_INCREASE_CA: optval = rack->r_ctl.rack_per_of_gp_ss; break; case TCP_RACK_PACING_DIVISOR: optval = rack->r_ctl.pace_len_divisor; break; case TCP_BBR_RACK_RTT_USE: optval = rack->r_ctl.rc_rate_sample_method; break; case TCP_DELACK: optval = tp->t_delayed_ack; break; case TCP_DATA_AFTER_CLOSE: optval = rack->rc_allow_data_af_clo; break; case TCP_SHARED_CWND_TIME_LIMIT: optval = rack->r_limit_scw; break; case TCP_RACK_TIMER_SLOP: optval = rack->r_ctl.timer_slop; break; default: return (tcp_default_ctloutput(tp, sopt)); break; } INP_WUNLOCK(inp); if (error == 0) { if (TCP_PACING_RATE_CAP) error = sooptcopyout(sopt, &loptval, sizeof loptval); else error = sooptcopyout(sopt, &optval, sizeof optval); } return (error); } static int rack_ctloutput(struct tcpcb *tp, struct sockopt *sopt) { if (sopt->sopt_dir == SOPT_SET) { return (rack_set_sockopt(tp, sopt)); } else if (sopt->sopt_dir == SOPT_GET) { return (rack_get_sockopt(tp, sopt)); } else { panic("%s: sopt_dir $%d", __func__, sopt->sopt_dir); } } static const char *rack_stack_names[] = { __XSTRING(STACKNAME), #ifdef STACKALIAS __XSTRING(STACKALIAS), #endif }; static int rack_ctor(void *mem, int32_t size, void *arg, int32_t how) { memset(mem, 0, size); return (0); } static void rack_dtor(void *mem, int32_t size, void *arg) { } static bool rack_mod_inited = false; static int tcp_addrack(module_t mod, int32_t type, void *data) { int32_t err = 0; int num_stacks; switch (type) { case MOD_LOAD: rack_zone = uma_zcreate(__XSTRING(MODNAME) "_map", sizeof(struct rack_sendmap), rack_ctor, rack_dtor, NULL, NULL, UMA_ALIGN_PTR, 0); rack_pcb_zone = uma_zcreate(__XSTRING(MODNAME) "_pcb", sizeof(struct tcp_rack), rack_ctor, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0); sysctl_ctx_init(&rack_sysctl_ctx); rack_sysctl_root = SYSCTL_ADD_NODE(&rack_sysctl_ctx, SYSCTL_STATIC_CHILDREN(_net_inet_tcp), OID_AUTO, #ifdef STACKALIAS __XSTRING(STACKALIAS), #else __XSTRING(STACKNAME), #endif CTLFLAG_RW | CTLFLAG_MPSAFE, 0, ""); if (rack_sysctl_root == NULL) { printf("Failed to add sysctl node\n"); err = EFAULT; goto free_uma; } rack_init_sysctls(); num_stacks = nitems(rack_stack_names); err = register_tcp_functions_as_names(&__tcp_rack, M_WAITOK, rack_stack_names, &num_stacks); if (err) { printf("Failed to register %s stack name for " "%s module\n", rack_stack_names[num_stacks], __XSTRING(MODNAME)); sysctl_ctx_free(&rack_sysctl_ctx); free_uma: uma_zdestroy(rack_zone); uma_zdestroy(rack_pcb_zone); rack_counter_destroy(); printf("Failed to register rack module -- err:%d\n", err); return (err); } tcp_lro_reg_mbufq(); rack_mod_inited = true; break; case MOD_QUIESCE: err = deregister_tcp_functions(&__tcp_rack, true, false); break; case MOD_UNLOAD: err = deregister_tcp_functions(&__tcp_rack, false, true); if (err == EBUSY) break; if (rack_mod_inited) { uma_zdestroy(rack_zone); uma_zdestroy(rack_pcb_zone); sysctl_ctx_free(&rack_sysctl_ctx); rack_counter_destroy(); rack_mod_inited = false; } tcp_lro_dereg_mbufq(); err = 0; break; default: return (EOPNOTSUPP); } return (err); } static moduledata_t tcp_rack = { .name = __XSTRING(MODNAME), .evhand = tcp_addrack, .priv = 0 }; MODULE_VERSION(MODNAME, 1); DECLARE_MODULE(MODNAME, tcp_rack, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY); MODULE_DEPEND(MODNAME, tcphpts, 1, 1, 1); #endif /* #if !defined(INET) && !defined(INET6) */