/*- * 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. * * $FreeBSD$ */ #ifndef _NETINET_TCP_RACK_H_ #define _NETINET_TCP_RACK_H_ #define RACK_ACKED 0x0001/* The remote endpoint acked this */ #define RACK_TO_MIXED 0x0002/* A timeout occurred that mixed the send order - not used */ #define RACK_DEFERRED 0x0004/* We can't use this for RTT calc - not used */ #define RACK_OVERMAX 0x0008/* We have more retran's then we can fit */ #define RACK_SACK_PASSED 0x0010/* A sack was done above this block */ #define RACK_WAS_SACKPASS 0x0020/* We retransmitted due to SACK pass */ #define RACK_HAS_FIN 0x0040/* segment is sent with fin */ #define RACK_TLP 0x0080/* segment sent as tail-loss-probe */ #define RACK_RWND_COLLAPSED 0x0100/* The peer collapsed the rwnd on the segment */ #define RACK_APP_LIMITED 0x0200/* We went app limited after this send */ #define RACK_WAS_ACKED 0x0400/* a RTO undid the ack, but it already had a rtt calc done */ #define RACK_HAS_SIN 0x0800/* SIN is on this guy */ #define RACK_NUM_OF_RETRANS 3 #define RACK_INITIAL_RTO 1000 /* 1 second in milli seconds */ #define RACK_REQ_AVG 4 /* Must be less than 256 */ struct rack_sendmap { uint32_t r_start; /* Sequence number of the segment */ uint32_t r_end; /* End seq, this is 1 beyond actually */ TAILQ_ENTRY(rack_sendmap) r_tnext; /* Time of transmit based next */ RB_ENTRY(rack_sendmap) r_next; /* RB Tree next */ uint32_t r_rtr_bytes; /* How many bytes have been retransmitted */ uint16_t r_rtr_cnt; /* Retran count, index this -1 to get time * sent */ uint16_t r_flags; /* Flags as defined above */ uint32_t r_tim_lastsent[RACK_NUM_OF_RETRANS]; uint32_t usec_orig_send; /* time of orginal send in useconds */ uint32_t r_nseq_appl; /* If this one is app limited, this is the nxt seq limited */ uint32_t r_ack_arrival; /* This is the time of ack-arrival (if SACK'd) */ uint8_t r_dupack; /* Dup ack count */ uint8_t r_in_tmap; /* Flag to see if its in the r_tnext array */ uint8_t r_limit_type; /* is this entry counted against a limit? */ uint8_t r_just_ret : 1, /* After sending, the next pkt was just returned, i.e. limited */ r_one_out_nr : 1, /* Special case 1 outstanding and not in recovery */ r_avail : 6; uint8_t r_resv[36]; }; RB_HEAD(rack_rb_tree_head, rack_sendmap); TAILQ_HEAD(rack_head, rack_sendmap); #define RACK_LIMIT_TYPE_SPLIT 1 /* * We use the rate sample structure to * assist in single sack/ack rate and rtt * calculation. In the future we will expand * this in BBR to do forward rate sample * b/w estimation. */ #define RACK_RTT_EMPTY 0x00000001 /* Nothing yet stored in RTT's */ #define RACK_RTT_VALID 0x00000002 /* We have at least one valid RTT */ struct rack_rtt_sample { uint32_t rs_flags; uint32_t rs_rtt_lowest; uint32_t rs_rtt_highest; uint32_t rs_rtt_cnt; uint32_t rs_us_rtt; int32_t confidence; uint64_t rs_rtt_tot; uint16_t rs_us_rtrcnt; }; #define RACK_LOG_TYPE_ACK 0x01 #define RACK_LOG_TYPE_OUT 0x02 #define RACK_LOG_TYPE_TO 0x03 #define RACK_LOG_TYPE_ALLOC 0x04 #define RACK_LOG_TYPE_FREE 0x05 struct rack_log { union { struct rack_sendmap *rsm; /* For alloc/free */ uint64_t sb_acc;/* For out/ack or t-o */ }; uint32_t th_seq; uint32_t th_ack; uint32_t snd_una; uint32_t snd_nxt; /* th_win for TYPE_ACK */ uint32_t snd_max; uint32_t blk_start[4]; uint32_t blk_end[4]; uint8_t type; uint8_t n_sackblks; uint16_t len; /* Timeout T3=1, TLP=2, RACK=3 */ }; /* * Magic numbers for logging timeout events if the * logging is enabled. */ #define RACK_TO_FRM_TMR 1 #define RACK_TO_FRM_TLP 2 #define RACK_TO_FRM_RACK 3 #define RACK_TO_FRM_KEEP 4 #define RACK_TO_FRM_PERSIST 5 #define RACK_TO_FRM_DELACK 6 struct rack_opts_stats { uint64_t tcp_rack_prop_rate; uint64_t tcp_rack_prop; uint64_t tcp_rack_tlp_reduce; uint64_t tcp_rack_early_recov; uint64_t tcp_rack_pace_always; uint64_t tcp_rack_pace_reduce; uint64_t tcp_rack_max_seg; uint64_t tcp_rack_prr_sendalot; uint64_t tcp_rack_min_to; uint64_t tcp_rack_early_seg; uint64_t tcp_rack_reord_thresh; uint64_t tcp_rack_reord_fade; uint64_t tcp_rack_tlp_thresh; uint64_t tcp_rack_pkt_delay; uint64_t tcp_rack_tlp_inc_var; uint64_t tcp_tlp_use; uint64_t tcp_rack_idle_reduce; uint64_t tcp_rack_idle_reduce_high; uint64_t rack_no_timer_in_hpts; uint64_t tcp_rack_min_pace_seg; uint64_t tcp_rack_pace_rate_ca; uint64_t tcp_rack_rr; uint64_t tcp_rack_do_detection; uint64_t tcp_rack_rrr_no_conf_rate; uint64_t tcp_initial_rate; uint64_t tcp_initial_win; uint64_t tcp_hdwr_pacing; uint64_t tcp_gp_inc_ss; uint64_t tcp_gp_inc_ca; uint64_t tcp_gp_inc_rec; uint64_t tcp_rack_force_max_seg; uint64_t tcp_rack_pace_rate_ss; uint64_t tcp_rack_pace_rate_rec; /* Temp counters for dsack */ uint64_t tcp_sack_path_1; uint64_t tcp_sack_path_2a; uint64_t tcp_sack_path_2b; uint64_t tcp_sack_path_3; uint64_t tcp_sack_path_4; /* non temp counters */ uint64_t tcp_rack_scwnd; uint64_t tcp_rack_noprr; uint64_t tcp_rack_cfg_rate; uint64_t tcp_timely_dyn; uint64_t tcp_rack_mbufq; uint64_t tcp_fillcw; uint64_t tcp_npush; uint64_t tcp_lscwnd; uint64_t tcp_profile; }; /* RTT shrink reasons */ #define RACK_RTTS_INIT 0 #define RACK_RTTS_NEWRTT 1 #define RACK_RTTS_EXITPROBE 2 #define RACK_RTTS_ENTERPROBE 3 #define RACK_RTTS_REACHTARGET 4 #define RACK_RTTS_SEEHBP 5 #define RACK_RTTS_NOBACKOFF 6 #define RACK_RTTS_SAFETY 7 #define RACK_USE_BEG 1 #define RACK_USE_END 2 #define RACK_USE_END_OR_THACK 3 #define TLP_USE_ID 1 /* Internet draft behavior */ #define TLP_USE_TWO_ONE 2 /* Use 2.1 behavior */ #define TLP_USE_TWO_TWO 3 /* Use 2.2 behavior */ #define RACK_MIN_BW 8000 /* 64kbps in Bps */ #define MIN_GP_WIN 6 /* We need at least 6 MSS in a GP measurement */ #ifdef _KERNEL #define RACK_OPTS_SIZE (sizeof(struct rack_opts_stats)/sizeof(uint64_t)) extern counter_u64_t rack_opts_arry[RACK_OPTS_SIZE]; #define RACK_OPTS_ADD(name, amm) counter_u64_add(rack_opts_arry[(offsetof(struct rack_opts_stats, name)/sizeof(uint64_t))], (amm)) #define RACK_OPTS_INC(name) RACK_OPTS_ADD(name, 1) #endif /* * As we get each SACK we wade through the * rc_map and mark off what is acked. * We also increment rc_sacked as well. * * We also pay attention to missing entries * based on the time and possibly mark them * for retransmit. If we do and we are not already * in recovery we enter recovery. In doing * so we claer prr_delivered/holes_rxt and prr_sent_dur_rec. * We also setup rc_next/rc_snd_nxt/rc_send_end so * we will know where to send from. When not in * recovery rc_next will be NULL and rc_snd_nxt should * equal snd_max. * * Whenever we retransmit from recovery we increment * rc_holes_rxt as we retran a block and mark it as retransmitted * with the time it was sent. During non-recovery sending we * add to our map and note the time down of any send expanding * the rc_map at the tail and moving rc_snd_nxt up with snd_max. * * In recovery during SACK/ACK processing if a chunk has * been retransmitted and it is now acked, we decrement rc_holes_rxt. * When we retransmit from the scoreboard we use * rc_next and rc_snd_nxt/rc_send_end to help us * find what needs to be retran. * * To calculate pipe we simply take (snd_max - snd_una) + rc_holes_rxt * This gets us the effect of RFC6675 pipe, counting twice for * bytes retransmitted. */ #define TT_RACK_FR_TMR 0x2000 /* * Locking for the rack control block. * a) Locked by INP_WLOCK * b) Locked by the hpts-mutex * */ #define RACK_GP_HIST 4 /* How much goodput history do we maintain? */ struct rack_control { /* Second cache line 0x40 from tcp_rack */ struct rack_rb_tree_head rc_mtree; /* Tree of all segments Lock(a) */ struct rack_head rc_tmap; /* List in transmit order Lock(a) */ struct rack_sendmap *rc_tlpsend; /* Remembered place for * tlp_sending Lock(a) */ struct rack_sendmap *rc_resend; /* something we have been asked to * resend */ uint32_t input_pkt; uint32_t saved_input_pkt; uint32_t rc_hpts_flags; uint32_t rc_fixed_pacing_rate_ca; uint32_t rc_fixed_pacing_rate_rec; uint32_t rc_fixed_pacing_rate_ss; uint32_t cwnd_to_use; /* The cwnd in use */ uint32_t rc_timer_exp; /* If a timer ticks of expiry */ uint32_t rc_rack_min_rtt; /* lowest RTT seen Lock(a) */ uint32_t rc_rack_largest_cwnd; /* Largest CWND we have seen Lock(a) */ /* Third Cache line 0x80 */ struct rack_head rc_free; /* Allocation array */ uint32_t rc_time_last_sent; /* Time we last sent some data and * logged it Lock(a). */ uint32_t rc_reorder_ts; /* Last time we saw reordering Lock(a) */ uint32_t rc_tlp_new_data; /* we need to send new-data on a TLP * Lock(a) */ uint32_t rc_prr_out; /* bytes sent during recovery Lock(a) */ uint32_t rc_prr_recovery_fs; /* recovery fs point Lock(a) */ uint32_t rc_prr_sndcnt; /* Prr sndcnt Lock(a) */ uint32_t rc_sacked; /* Tot sacked on scoreboard Lock(a) */ uint32_t xxx_rc_last_tlp_seq; /* Last tlp sequence Lock(a) */ uint32_t rc_prr_delivered; /* during recovery prr var Lock(a) */ uint16_t rc_tlp_cnt_out; /* count of times we have sent a TLP without new data */ uint16_t xxx_rc_tlp_seg_send_cnt; /* Number of times we have TLP sent * rc_last_tlp_seq Lock(a) */ uint32_t rc_loss_count; /* How many bytes have been retransmitted * Lock(a) */ uint32_t rc_reorder_fade; /* Socket option value Lock(a) */ /* Forth cache line 0xc0 */ /* Times */ uint32_t rc_rack_tmit_time; /* Rack transmit time Lock(a) */ uint32_t rc_holes_rxt; /* Tot retraned from scoreboard Lock(a) */ /* Variables to track bad retransmits and recover */ uint32_t rc_rsm_start; /* RSM seq number we retransmitted Lock(a) */ uint32_t rc_cwnd_at; /* cwnd at the retransmit Lock(a) */ uint32_t rc_ssthresh_at;/* ssthresh at the retransmit Lock(a) */ uint32_t rc_num_maps_alloced; /* Number of map blocks (sacks) we * have allocated */ uint32_t rc_rcvtime; /* When we last received data */ uint32_t rc_num_split_allocs; /* num split map entries allocated */ uint32_t rc_last_output_to; uint32_t rc_went_idle_time; struct rack_sendmap *rc_sacklast; /* sack remembered place * Lock(a) */ struct rack_sendmap *rc_rsm_at_retran; /* Debug variable kept for * cache line alignment * Lock(a) */ struct rack_sendmap *rc_first_appl; /* Pointer to first app limited */ struct rack_sendmap *rc_end_appl; /* Pointer to last app limited */ /* Cache line split 0x100 */ struct sack_filter rack_sf; /* Cache line split 0x140 */ /* Flags for various things */ uint32_t last_pacing_time; uint32_t rc_pace_max_segs; uint32_t rc_pace_min_segs; uint32_t rc_app_limited_cnt; uint16_t rack_per_of_gp_ss; /* 100 = 100%, so from 65536 = 655 x bw */ uint16_t rack_per_of_gp_ca; /* 100 = 100%, so from 65536 = 655 x bw */ uint16_t rack_per_of_gp_rec; /* 100 = 100%, so from 65536 = 655 x bw, 0=off */ uint16_t rack_per_of_gp_probertt; /* 100 = 100%, so from 65536 = 655 x bw, 0=off */ uint32_t rc_high_rwnd; uint32_t ack_count; uint32_t sack_count; uint32_t sack_noextra_move; uint32_t sack_moved_extra; struct rack_rtt_sample rack_rs; const struct tcp_hwrate_limit_table *crte; uint32_t rc_agg_early; uint32_t rc_agg_delayed; uint32_t rc_tlp_rxt_last_time; uint32_t rc_saved_cwnd; uint32_t rc_gp_output_ts; uint32_t rc_gp_cumack_ts; struct timeval act_rcv_time; struct timeval rc_last_time_decay; /* SAD time decay happened here */ uint64_t gp_bw; uint64_t init_rate; #ifdef NETFLIX_SHARED_CWND struct shared_cwnd *rc_scw; #endif uint64_t last_gp_comp_bw; uint64_t last_max_bw; /* Our calculated max b/w last */ struct time_filter_small rc_gp_min_rtt; int32_t rc_rtt_diff; /* Timely style rtt diff of our gp_srtt */ uint32_t rc_gp_srtt; /* Current GP srtt */ uint32_t rc_prev_gp_srtt; /* Previous RTT */ uint32_t rc_entry_gp_rtt; /* Entry to PRTT gp-rtt */ uint32_t rc_loss_at_start; /* At measurement window where was our lost value */ uint32_t forced_ack_ts; uint32_t rc_lower_rtt_us_cts; /* Time our GP rtt was last lowered */ uint32_t rc_time_probertt_entered; uint32_t rc_time_probertt_starts; uint32_t rc_lowest_us_rtt; uint32_t rc_highest_us_rtt; uint32_t rc_last_us_rtt; uint32_t rc_time_of_last_probertt; uint32_t rc_target_probertt_flight; uint32_t rc_probertt_sndmax_atexit; /* Highest sent to in probe-rtt */ uint32_t rc_gp_lowrtt; /* Lowest rtt seen during GPUT measurement */ uint32_t rc_gp_high_rwnd; /* Highest rwnd seen during GPUT measurement */ int32_t rc_scw_index; uint32_t rc_tlp_threshold; /* Socket option value Lock(a) */ uint16_t rc_early_recovery_segs; /* Socket option value Lock(a) */ uint16_t rc_reorder_shift; /* Socket option value Lock(a) */ uint16_t rc_pkt_delay; /* Socket option value Lock(a) */ uint8_t rc_no_push_at_mrtt; /* No push when we exceed max rtt */ uint8_t num_avg; /* average count before we go to normal decay */ uint8_t rc_prop_rate; /* Socket option value Lock(a) */ uint8_t rc_prop_reduce; /* Socket option value Lock(a) */ uint8_t rc_tlp_cwnd_reduce; /* Socket option value Lock(a) */ uint8_t rc_early_recovery; /* Socket option value Lock(a) */ uint8_t rc_prr_sendalot;/* Socket option value Lock(a) */ uint8_t rc_min_to; /* Socket option value Lock(a) */ uint8_t rc_rate_sample_method; uint8_t rc_gp_hist_idx; }; #define RACK_TIMELY_CNT_BOOST 5 /* At 5th increase boost */ #define RACK_MINRTT_FILTER_TIM 10 /* Seconds */ #ifdef _KERNEL struct tcp_rack { /* First cache line 0x00 */ TAILQ_ENTRY(tcp_rack) r_hpts; /* hptsi queue next Lock(b) */ int32_t(*r_substate) (struct mbuf *, struct tcphdr *, struct socket *, struct tcpcb *, struct tcpopt *, int32_t, int32_t, uint32_t, int, int, uint8_t); /* Lock(a) */ struct tcpcb *rc_tp; /* The tcpcb Lock(a) */ struct inpcb *rc_inp; /* The inpcb Lock(a) */ uint32_t rc_free_cnt; /* Number of free entries on the rc_free list * Lock(a) */ uint32_t rc_rack_rtt; /* RACK-RTT Lock(a) */ uint16_t r_mbuf_queue : 1, /* Do we do mbuf queue for non-paced */ rtt_limit_mul : 4, /* muliply this by low rtt */ r_limit_scw : 1, r_avail_bits : 10; /* Available */ uint16_t rc_user_set_max_segs; /* Socket option value Lock(a) */ uint16_t forced_ack : 1, rc_gp_incr : 1, rc_gp_bwred : 1, rc_gp_timely_inc_cnt : 3, rc_gp_timely_dec_cnt : 3, rc_not_backing_off: 1, rc_highly_buffered: 1, /* The path is highly buffered */ rc_dragged_bottom: 1, rc_dack_mode : 1, /* Mac O/S emulation of d-ack */ rc_dack_toggle : 1, /* For Mac O/S emulation of d-ack */ pacing_longer_than_rtt : 1, rc_gp_filled : 1; uint8_t r_state; /* Current rack state Lock(a) */ uint8_t rc_tmr_stopped : 7, t_timers_stopped : 1; uint8_t rc_enobuf : 7, /* count of enobufs on connection provides */ rc_on_min_to : 1; uint8_t r_timer_override : 1, /* hpts override Lock(a) */ r_is_v6 : 1, /* V6 pcb Lock(a) */ rc_in_persist : 1, rc_tlp_in_progress : 1, rc_always_pace : 1, /* Socket option value Lock(a) */ rc_pace_to_cwnd : 1, rc_pace_fill_if_rttin_range : 1, xxx_avail_bits : 1; uint8_t app_limited_needs_set : 1, use_fixed_rate : 1, rc_has_collapsed : 1, r_rep_attack : 1, r_rep_reverse : 1, rack_hdrw_pacing : 1, /* We are doing Hardware pacing */ rack_hdw_pace_ena : 1, /* Is hardware pacing enabled? */ rack_attempt_hdwr_pace : 1; /* Did we attempt hdwr pacing (if allowed) */ uint8_t rack_tlp_threshold_use : 3, /* only 1, 2 and 3 used so far */ rack_rec_nonrxt_use_cr : 1, rack_enable_scwnd : 1, rack_attempted_scwnd : 1, rack_no_prr : 1, rack_scwnd_is_idle : 1; uint8_t rc_allow_data_af_clo: 1, delayed_ack : 1, set_pacing_done_a_iw : 1, use_rack_rr : 1, alloc_limit_reported : 1, sack_attack_disable : 1, do_detection : 1, rc_force_max_seg : 1; uint8_t rack_cwnd_limited : 1, r_early : 1, r_late : 1, r_running_early : 1, r_running_late : 1, r_wanted_output: 1, r_rr_config : 2; uint16_t rc_init_win : 8, rc_gp_rtt_set : 1, rc_gp_dyn_mul : 1, rc_gp_saw_rec : 1, rc_gp_saw_ca : 1, rc_gp_saw_ss : 1, rc_gp_no_rec_chg : 1, in_probe_rtt : 1, measure_saw_probe_rtt : 1; /* Cache line 2 0x40 */ struct rack_control r_ctl; } __aligned(CACHE_LINE_SIZE); #endif #endif