1 /*- 2 * Copyright (c) 2016-2019 3 * Netflix Inc. 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 * 27 */ 28 /** 29 * Author: Randall Stewart <rrs@netflix.com> 30 * This work is based on the ACM Queue paper 31 * BBR - Congestion Based Congestion Control 32 * and also numerous discussions with Neal, Yuchung and Van. 33 */ 34 35 #include <sys/cdefs.h> 36 __FBSDID("$FreeBSD$"); 37 38 #include "opt_inet.h" 39 #include "opt_inet6.h" 40 #include "opt_ipsec.h" 41 #include "opt_tcpdebug.h" 42 #include "opt_ratelimit.h" 43 #include "opt_kern_tls.h" 44 #include <sys/param.h> 45 #include <sys/module.h> 46 #include <sys/kernel.h> 47 #ifdef TCP_HHOOK 48 #include <sys/hhook.h> 49 #endif 50 #include <sys/malloc.h> 51 #include <sys/mbuf.h> 52 #include <sys/proc.h> 53 #include <sys/socket.h> 54 #include <sys/socketvar.h> 55 #ifdef KERN_TLS 56 #include <sys/ktls.h> 57 #endif 58 #include <sys/sysctl.h> 59 #include <sys/systm.h> 60 #include <sys/qmath.h> 61 #include <sys/tree.h> 62 #ifdef NETFLIX_STATS 63 #include <sys/stats.h> /* Must come after qmath.h and tree.h */ 64 #endif 65 #include <sys/refcount.h> 66 #include <sys/queue.h> 67 #include <sys/eventhandler.h> 68 #include <sys/smp.h> 69 #include <sys/kthread.h> 70 #include <sys/lock.h> 71 #include <sys/mutex.h> 72 #include <sys/tim_filter.h> 73 #include <sys/time.h> 74 #include <vm/uma.h> 75 #include <sys/kern_prefetch.h> 76 77 #include <net/route.h> 78 #include <net/vnet.h> 79 80 #define TCPSTATES /* for logging */ 81 82 #include <netinet/in.h> 83 #include <netinet/in_kdtrace.h> 84 #include <netinet/in_pcb.h> 85 #include <netinet/ip.h> 86 #include <netinet/ip_icmp.h> /* required for icmp_var.h */ 87 #include <netinet/icmp_var.h> /* for ICMP_BANDLIM */ 88 #include <netinet/ip_var.h> 89 #include <netinet/ip6.h> 90 #include <netinet6/in6_pcb.h> 91 #include <netinet6/ip6_var.h> 92 #define TCPOUTFLAGS 93 #include <netinet/tcp.h> 94 #include <netinet/tcp_fsm.h> 95 #include <netinet/tcp_seq.h> 96 #include <netinet/tcp_timer.h> 97 #include <netinet/tcp_var.h> 98 #include <netinet/tcpip.h> 99 #include <netinet/tcp_hpts.h> 100 #include <netinet/cc/cc.h> 101 #include <netinet/tcp_log_buf.h> 102 #include <netinet/tcp_ratelimit.h> 103 #include <netinet/tcp_lro.h> 104 #ifdef TCPDEBUG 105 #include <netinet/tcp_debug.h> 106 #endif /* TCPDEBUG */ 107 #ifdef TCP_OFFLOAD 108 #include <netinet/tcp_offload.h> 109 #endif 110 #ifdef INET6 111 #include <netinet6/tcp6_var.h> 112 #endif 113 #include <netinet/tcp_fastopen.h> 114 115 #include <netipsec/ipsec_support.h> 116 #include <net/if.h> 117 #include <net/if_var.h> 118 #include <net/ethernet.h> 119 120 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 121 #include <netipsec/ipsec.h> 122 #include <netipsec/ipsec6.h> 123 #endif /* IPSEC */ 124 125 #include <netinet/udp.h> 126 #include <netinet/udp_var.h> 127 #include <machine/in_cksum.h> 128 129 #ifdef MAC 130 #include <security/mac/mac_framework.h> 131 #endif 132 133 #include "sack_filter.h" 134 #include "tcp_bbr.h" 135 #include "rack_bbr_common.h" 136 uma_zone_t bbr_zone; 137 uma_zone_t bbr_pcb_zone; 138 139 struct sysctl_ctx_list bbr_sysctl_ctx; 140 struct sysctl_oid *bbr_sysctl_root; 141 142 #define TCPT_RANGESET_NOSLOP(tv, value, tvmin, tvmax) do { \ 143 (tv) = (value); \ 144 if ((u_long)(tv) < (u_long)(tvmin)) \ 145 (tv) = (tvmin); \ 146 if ((u_long)(tv) > (u_long)(tvmax)) \ 147 (tv) = (tvmax); \ 148 } while(0) 149 150 /*#define BBR_INVARIANT 1*/ 151 152 /* 153 * initial window 154 */ 155 static uint32_t bbr_def_init_win = 10; 156 static int32_t bbr_persist_min = 250000; /* 250ms */ 157 static int32_t bbr_persist_max = 1000000; /* 1 Second */ 158 static int32_t bbr_cwnd_may_shrink = 0; 159 static int32_t bbr_cwndtarget_rtt_touse = BBR_RTT_PROP; 160 static int32_t bbr_num_pktepo_for_del_limit = BBR_NUM_RTTS_FOR_DEL_LIMIT; 161 static int32_t bbr_hardware_pacing_limit = 8000; 162 static int32_t bbr_quanta = 3; /* How much extra quanta do we get? */ 163 static int32_t bbr_no_retran = 0; 164 static int32_t bbr_tcp_map_entries_limit = 1500; 165 static int32_t bbr_tcp_map_split_limit = 256; 166 167 static int32_t bbr_error_base_paceout = 10000; /* usec to pace */ 168 static int32_t bbr_max_net_error_cnt = 10; 169 /* Should the following be dynamic too -- loss wise */ 170 static int32_t bbr_rtt_gain_thresh = 0; 171 /* Measurement controls */ 172 static int32_t bbr_use_google_algo = 1; 173 static int32_t bbr_ts_limiting = 1; 174 static int32_t bbr_ts_can_raise = 0; 175 static int32_t bbr_do_red = 600; 176 static int32_t bbr_red_scale = 20000; 177 static int32_t bbr_red_mul = 1; 178 static int32_t bbr_red_div = 2; 179 static int32_t bbr_red_growth_restrict = 1; 180 static int32_t bbr_target_is_bbunit = 0; 181 static int32_t bbr_drop_limit = 0; 182 /* 183 * How much gain do we need to see to 184 * stay in startup? 185 */ 186 static int32_t bbr_marks_rxt_sack_passed = 0; 187 static int32_t bbr_start_exit = 25; 188 static int32_t bbr_low_start_exit = 25; /* When we are in reduced gain */ 189 static int32_t bbr_startup_loss_thresh = 2000; /* 20.00% loss */ 190 static int32_t bbr_hptsi_max_mul = 1; /* These two mul/div assure a min pacing */ 191 static int32_t bbr_hptsi_max_div = 2; /* time, 0 means turned off. We need this 192 * if we go back ever to where the pacer 193 * has priority over timers. 194 */ 195 static int32_t bbr_policer_call_from_rack_to = 0; 196 static int32_t bbr_policer_detection_enabled = 1; 197 static int32_t bbr_min_measurements_req = 1; /* We need at least 2 198 * measurments before we are 199 * "good" note that 2 == 1. 200 * This is because we use a > 201 * comparison. This means if 202 * min_measure was 0, it takes 203 * num-measures > min(0) and 204 * you get 1 measurement and 205 * you are good. Set to 1, you 206 * have to have two 207 * measurements (this is done 208 * to prevent it from being ok 209 * to have no measurements). */ 210 static int32_t bbr_no_pacing_until = 4; 211 212 static int32_t bbr_min_usec_delta = 20000; /* 20,000 usecs */ 213 static int32_t bbr_min_peer_delta = 20; /* 20 units */ 214 static int32_t bbr_delta_percent = 150; /* 15.0 % */ 215 216 static int32_t bbr_target_cwnd_mult_limit = 8; 217 /* 218 * bbr_cwnd_min_val is the number of 219 * segments we hold to in the RTT probe 220 * state typically 4. 221 */ 222 static int32_t bbr_cwnd_min_val = BBR_PROBERTT_NUM_MSS; 223 224 225 static int32_t bbr_cwnd_min_val_hs = BBR_HIGHSPEED_NUM_MSS; 226 227 static int32_t bbr_gain_to_target = 1; 228 static int32_t bbr_gain_gets_extra_too = 1; 229 /* 230 * bbr_high_gain is the 2/ln(2) value we need 231 * to double the sending rate in startup. This 232 * is used for both cwnd and hptsi gain's. 233 */ 234 static int32_t bbr_high_gain = BBR_UNIT * 2885 / 1000 + 1; 235 static int32_t bbr_startup_lower = BBR_UNIT * 1500 / 1000 + 1; 236 static int32_t bbr_use_lower_gain_in_startup = 1; 237 238 /* thresholds for reduction on drain in sub-states/drain */ 239 static int32_t bbr_drain_rtt = BBR_SRTT; 240 static int32_t bbr_drain_floor = 88; 241 static int32_t google_allow_early_out = 1; 242 static int32_t google_consider_lost = 1; 243 static int32_t bbr_drain_drop_mul = 4; 244 static int32_t bbr_drain_drop_div = 5; 245 static int32_t bbr_rand_ot = 50; 246 static int32_t bbr_can_force_probertt = 0; 247 static int32_t bbr_can_adjust_probertt = 1; 248 static int32_t bbr_probertt_sets_rtt = 0; 249 static int32_t bbr_can_use_ts_for_rtt = 1; 250 static int32_t bbr_is_ratio = 0; 251 static int32_t bbr_sub_drain_app_limit = 1; 252 static int32_t bbr_prtt_slam_cwnd = 1; 253 static int32_t bbr_sub_drain_slam_cwnd = 1; 254 static int32_t bbr_slam_cwnd_in_main_drain = 1; 255 static int32_t bbr_filter_len_sec = 6; /* How long does the rttProp filter 256 * hold */ 257 static uint32_t bbr_rtt_probe_limit = (USECS_IN_SECOND * 4); 258 /* 259 * bbr_drain_gain is the reverse of the high_gain 260 * designed to drain back out the standing queue 261 * that is formed in startup by causing a larger 262 * hptsi gain and thus drainging the packets 263 * in flight. 264 */ 265 static int32_t bbr_drain_gain = BBR_UNIT * 1000 / 2885; 266 static int32_t bbr_rttprobe_gain = 192; 267 268 /* 269 * The cwnd_gain is the default cwnd gain applied when 270 * calculating a target cwnd. Note that the cwnd is 271 * a secondary factor in the way BBR works (see the 272 * paper and think about it, it will take some time). 273 * Basically the hptsi_gain spreads the packets out 274 * so you never get more than BDP to the peer even 275 * if the cwnd is high. In our implemenation that 276 * means in non-recovery/retransmission scenarios 277 * cwnd will never be reached by the flight-size. 278 */ 279 static int32_t bbr_cwnd_gain = BBR_UNIT * 2; 280 static int32_t bbr_tlp_type_to_use = BBR_SRTT; 281 static int32_t bbr_delack_time = 100000; /* 100ms in useconds */ 282 static int32_t bbr_sack_not_required = 0; /* set to one to allow non-sack to use bbr */ 283 static int32_t bbr_initial_bw_bps = 62500; /* 500kbps in bytes ps */ 284 static int32_t bbr_ignore_data_after_close = 1; 285 static int16_t bbr_hptsi_gain[] = { 286 (BBR_UNIT *5 / 4), 287 (BBR_UNIT * 3 / 4), 288 BBR_UNIT, 289 BBR_UNIT, 290 BBR_UNIT, 291 BBR_UNIT, 292 BBR_UNIT, 293 BBR_UNIT 294 }; 295 int32_t bbr_use_rack_resend_cheat = 1; 296 int32_t bbr_sends_full_iwnd = 1; 297 298 #define BBR_HPTSI_GAIN_MAX 8 299 /* 300 * The BBR module incorporates a number of 301 * TCP ideas that have been put out into the IETF 302 * over the last few years: 303 * - Yuchung Cheng's RACK TCP (for which its named) that 304 * will stop us using the number of dup acks and instead 305 * use time as the gage of when we retransmit. 306 * - Reorder Detection of RFC4737 and the Tail-Loss probe draft 307 * of Dukkipati et.al. 308 * - Van Jacobson's et.al BBR. 309 * 310 * RACK depends on SACK, so if an endpoint arrives that 311 * cannot do SACK the state machine below will shuttle the 312 * connection back to using the "default" TCP stack that is 313 * in FreeBSD. 314 * 315 * To implement BBR and RACK the original TCP stack was first decomposed 316 * into a functional state machine with individual states 317 * for each of the possible TCP connection states. The do_segement 318 * functions role in life is to mandate the connection supports SACK 319 * initially and then assure that the RACK state matches the conenction 320 * state before calling the states do_segment function. Data processing 321 * of inbound segments also now happens in the hpts_do_segment in general 322 * with only one exception. This is so we can keep the connection on 323 * a single CPU. 324 * 325 * Each state is simplified due to the fact that the original do_segment 326 * has been decomposed and we *know* what state we are in (no 327 * switches on the state) and all tests for SACK are gone. This 328 * greatly simplifies what each state does. 329 * 330 * TCP output is also over-written with a new version since it 331 * must maintain the new rack scoreboard and has had hptsi 332 * integrated as a requirment. Still todo is to eliminate the 333 * use of the callout_() system and use the hpts for all 334 * timers as well. 335 */ 336 static uint32_t bbr_rtt_probe_time = 200000; /* 200ms in micro seconds */ 337 static uint32_t bbr_rtt_probe_cwndtarg = 4; /* How many mss's outstanding */ 338 static const int32_t bbr_min_req_free = 2; /* The min we must have on the 339 * free list */ 340 static int32_t bbr_tlp_thresh = 1; 341 static int32_t bbr_reorder_thresh = 2; 342 static int32_t bbr_reorder_fade = 60000000; /* 0 - never fade, def 343 * 60,000,000 - 60 seconds */ 344 static int32_t bbr_pkt_delay = 1000; 345 static int32_t bbr_min_to = 1000; /* Number of usec's minimum timeout */ 346 static int32_t bbr_incr_timers = 1; 347 348 static int32_t bbr_tlp_min = 10000; /* 10ms in usecs */ 349 static int32_t bbr_delayed_ack_time = 200000; /* 200ms in usecs */ 350 static int32_t bbr_exit_startup_at_loss = 1; 351 352 /* 353 * bbr_lt_bw_ratio is 1/8th 354 * bbr_lt_bw_diff is < 4 Kbit/sec 355 */ 356 static uint64_t bbr_lt_bw_diff = 4000 / 8; /* In bytes per second */ 357 static uint64_t bbr_lt_bw_ratio = 8; /* For 1/8th */ 358 static uint32_t bbr_lt_bw_max_rtts = 48; /* How many rtt's do we use 359 * the lt_bw for */ 360 static uint32_t bbr_lt_intvl_min_rtts = 4; /* Min num of RTT's to measure 361 * lt_bw */ 362 static int32_t bbr_lt_intvl_fp = 0; /* False positive epoch diff */ 363 static int32_t bbr_lt_loss_thresh = 196; /* Lost vs delivered % */ 364 static int32_t bbr_lt_fd_thresh = 100; /* false detection % */ 365 366 static int32_t bbr_verbose_logging = 0; 367 /* 368 * Currently regular tcp has a rto_min of 30ms 369 * the backoff goes 12 times so that ends up 370 * being a total of 122.850 seconds before a 371 * connection is killed. 372 */ 373 static int32_t bbr_rto_min_ms = 30; /* 30ms same as main freebsd */ 374 static int32_t bbr_rto_max_sec = 4; /* 4 seconds */ 375 376 /****************************************************/ 377 /* DEFAULT TSO SIZING (cpu performance impacting) */ 378 /****************************************************/ 379 /* What amount is our formula using to get TSO size */ 380 static int32_t bbr_hptsi_per_second = 1000; 381 382 /* 383 * For hptsi under bbr_cross_over connections what is delay 384 * target 7ms (in usec) combined with a seg_max of 2 385 * gets us close to identical google behavior in 386 * TSO size selection (possibly more 1MSS sends). 387 */ 388 static int32_t bbr_hptsi_segments_delay_tar = 7000; 389 390 /* Does pacing delay include overhead's in its time calculations? */ 391 static int32_t bbr_include_enet_oh = 0; 392 static int32_t bbr_include_ip_oh = 1; 393 static int32_t bbr_include_tcp_oh = 1; 394 static int32_t bbr_google_discount = 10; 395 396 /* Do we use (nf mode) pkt-epoch to drive us or rttProp? */ 397 static int32_t bbr_state_is_pkt_epoch = 0; 398 static int32_t bbr_state_drain_2_tar = 1; 399 /* What is the max the 0 - bbr_cross_over MBPS TSO target 400 * can reach using our delay target. Note that this 401 * value becomes the floor for the cross over 402 * algorithm. 403 */ 404 static int32_t bbr_hptsi_segments_max = 2; 405 static int32_t bbr_hptsi_segments_floor = 1; 406 static int32_t bbr_hptsi_utter_max = 0; 407 408 /* What is the min the 0 - bbr_cross-over MBPS TSO target can be */ 409 static int32_t bbr_hptsi_bytes_min = 1460; 410 static int32_t bbr_all_get_min = 0; 411 412 /* Cross over point from algo-a to algo-b */ 413 static uint32_t bbr_cross_over = TWENTY_THREE_MBPS; 414 415 /* Do we deal with our restart state? */ 416 static int32_t bbr_uses_idle_restart = 0; 417 static int32_t bbr_idle_restart_threshold = 100000; /* 100ms in useconds */ 418 419 /* Do we allow hardware pacing? */ 420 static int32_t bbr_allow_hdwr_pacing = 0; 421 static int32_t bbr_hdwr_pace_adjust = 2; /* multipler when we calc the tso size */ 422 static int32_t bbr_hdwr_pace_floor = 1; 423 static int32_t bbr_hdwr_pacing_delay_cnt = 10; 424 425 /****************************************************/ 426 static int32_t bbr_resends_use_tso = 0; 427 static int32_t bbr_tlp_max_resend = 2; 428 static int32_t bbr_sack_block_limit = 128; 429 430 #define BBR_MAX_STAT 19 431 counter_u64_t bbr_state_time[BBR_MAX_STAT]; 432 counter_u64_t bbr_state_lost[BBR_MAX_STAT]; 433 counter_u64_t bbr_state_resend[BBR_MAX_STAT]; 434 counter_u64_t bbr_stat_arry[BBR_STAT_SIZE]; 435 counter_u64_t bbr_opts_arry[BBR_OPTS_SIZE]; 436 counter_u64_t bbr_out_size[TCP_MSS_ACCT_SIZE]; 437 counter_u64_t bbr_flows_whdwr_pacing; 438 counter_u64_t bbr_flows_nohdwr_pacing; 439 440 counter_u64_t bbr_nohdwr_pacing_enobuf; 441 counter_u64_t bbr_hdwr_pacing_enobuf; 442 443 static inline uint64_t bbr_get_bw(struct tcp_bbr *bbr); 444 445 /* 446 * Static defintions we need for forward declarations. 447 */ 448 static uint32_t 449 bbr_get_pacing_length(struct tcp_bbr *bbr, uint16_t gain, 450 uint32_t useconds_time, uint64_t bw); 451 static uint32_t 452 bbr_get_a_state_target(struct tcp_bbr *bbr, uint32_t gain); 453 static void 454 bbr_set_state(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t win); 455 static void 456 bbr_set_probebw_gains(struct tcp_bbr *bbr, uint32_t cts, uint32_t losses); 457 static void 458 bbr_substate_change(struct tcp_bbr *bbr, uint32_t cts, int line, 459 int dolog); 460 static uint32_t 461 bbr_get_target_cwnd(struct tcp_bbr *bbr, uint64_t bw, uint32_t gain); 462 static void 463 bbr_state_change(struct tcp_bbr *bbr, uint32_t cts, int32_t epoch, 464 int32_t pkt_epoch, uint32_t losses); 465 static uint32_t 466 bbr_calc_thresh_rack(struct tcp_bbr *bbr, uint32_t srtt, uint32_t cts, struct bbr_sendmap *rsm); 467 static uint32_t bbr_initial_cwnd(struct tcp_bbr *bbr, struct tcpcb *tp); 468 static uint32_t 469 bbr_calc_thresh_tlp(struct tcpcb *tp, struct tcp_bbr *bbr, 470 struct bbr_sendmap *rsm, uint32_t srtt, 471 uint32_t cts); 472 static void 473 bbr_exit_persist(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts, 474 int32_t line); 475 static void 476 bbr_set_state_target(struct tcp_bbr *bbr, int line); 477 static void 478 bbr_enter_probe_rtt(struct tcp_bbr *bbr, uint32_t cts, int32_t line); 479 480 static void 481 bbr_log_progress_event(struct tcp_bbr *bbr, struct tcpcb *tp, uint32_t tick, int event, int line); 482 483 static void 484 tcp_bbr_tso_size_check(struct tcp_bbr *bbr, uint32_t cts); 485 486 static void 487 bbr_setup_red_bw(struct tcp_bbr *bbr, uint32_t cts); 488 489 static void 490 bbr_log_rtt_shrinks(struct tcp_bbr *bbr, uint32_t cts, uint32_t applied, uint32_t rtt, 491 uint32_t line, uint8_t is_start, uint16_t set); 492 493 static struct bbr_sendmap * 494 bbr_find_lowest_rsm(struct tcp_bbr *bbr); 495 static __inline uint32_t 496 bbr_get_rtt(struct tcp_bbr *bbr, int32_t rtt_type); 497 static void 498 bbr_log_to_start(struct tcp_bbr *bbr, uint32_t cts, uint32_t to, int32_t slot, uint8_t which); 499 500 static void 501 bbr_log_timer_var(struct tcp_bbr *bbr, int mode, uint32_t cts, uint32_t time_since_sent, uint32_t srtt, 502 uint32_t thresh, uint32_t to); 503 static void 504 bbr_log_hpts_diag(struct tcp_bbr *bbr, uint32_t cts, struct hpts_diag *diag); 505 506 static void 507 bbr_log_type_bbrsnd(struct tcp_bbr *bbr, uint32_t len, uint32_t slot, 508 uint32_t del_by, uint32_t cts, uint32_t sloton, uint32_t prev_delay); 509 510 static void 511 bbr_enter_persist(struct tcpcb *tp, struct tcp_bbr *bbr, 512 uint32_t cts, int32_t line); 513 static void 514 bbr_stop_all_timers(struct tcpcb *tp); 515 static void 516 bbr_exit_probe_rtt(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts); 517 static void 518 bbr_check_probe_rtt_limits(struct tcp_bbr *bbr, uint32_t cts); 519 static void 520 bbr_timer_cancel(struct tcp_bbr *bbr, int32_t line, uint32_t cts); 521 522 523 static void 524 bbr_log_pacing_delay_calc(struct tcp_bbr *bbr, uint16_t gain, uint32_t len, 525 uint32_t cts, uint32_t usecs, uint64_t bw, uint32_t override, int mod); 526 527 static inline uint8_t 528 bbr_state_val(struct tcp_bbr *bbr) 529 { 530 return(bbr->rc_bbr_substate); 531 } 532 533 static inline uint32_t 534 get_min_cwnd(struct tcp_bbr *bbr) 535 { 536 int mss; 537 538 mss = min((bbr->rc_tp->t_maxseg - bbr->rc_last_options), bbr->r_ctl.rc_pace_max_segs); 539 if (bbr_get_rtt(bbr, BBR_RTT_PROP) < BBR_HIGH_SPEED) 540 return (bbr_cwnd_min_val_hs * mss); 541 else 542 return (bbr_cwnd_min_val * mss); 543 } 544 545 static uint32_t 546 bbr_get_persists_timer_val(struct tcpcb *tp, struct tcp_bbr *bbr) 547 { 548 uint64_t srtt, var; 549 uint64_t ret_val; 550 551 bbr->r_ctl.rc_hpts_flags |= PACE_TMR_PERSIT; 552 if (tp->t_srtt == 0) { 553 srtt = (uint64_t)BBR_INITIAL_RTO; 554 var = 0; 555 } else { 556 srtt = ((uint64_t)TICKS_2_USEC(tp->t_srtt) >> TCP_RTT_SHIFT); 557 var = ((uint64_t)TICKS_2_USEC(tp->t_rttvar) >> TCP_RTT_SHIFT); 558 } 559 TCPT_RANGESET_NOSLOP(ret_val, ((srtt + var) * tcp_backoff[tp->t_rxtshift]), 560 bbr_persist_min, bbr_persist_max); 561 return ((uint32_t)ret_val); 562 } 563 564 static uint32_t 565 bbr_timer_start(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts) 566 { 567 /* 568 * Start the FR timer, we do this based on getting the first one in 569 * the rc_tmap. Note that if its NULL we must stop the timer. in all 570 * events we need to stop the running timer (if its running) before 571 * starting the new one. 572 */ 573 uint32_t thresh, exp, to, srtt, time_since_sent, tstmp_touse; 574 int32_t idx; 575 int32_t is_tlp_timer = 0; 576 struct bbr_sendmap *rsm; 577 578 if (bbr->rc_all_timers_stopped) { 579 /* All timers have been stopped none are to run */ 580 return (0); 581 } 582 if (bbr->rc_in_persist) { 583 /* We can't start any timer in persists */ 584 return (bbr_get_persists_timer_val(tp, bbr)); 585 } 586 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_tmap); 587 if ((rsm == NULL) || 588 ((tp->t_flags & TF_SACK_PERMIT) == 0) || 589 (tp->t_state < TCPS_ESTABLISHED)) { 590 /* Nothing on the send map */ 591 activate_rxt: 592 if (SEQ_LT(tp->snd_una, tp->snd_max) || sbavail(&(tp->t_inpcb->inp_socket->so_snd))) { 593 uint64_t tov; 594 595 time_since_sent = 0; 596 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_tmap); 597 if (rsm) { 598 idx = rsm->r_rtr_cnt - 1; 599 if (TSTMP_GEQ(rsm->r_tim_lastsent[idx], bbr->r_ctl.rc_tlp_rxt_last_time)) 600 tstmp_touse = rsm->r_tim_lastsent[idx]; 601 else 602 tstmp_touse = bbr->r_ctl.rc_tlp_rxt_last_time; 603 if (TSTMP_GT(tstmp_touse, cts)) 604 time_since_sent = cts - tstmp_touse; 605 } 606 bbr->r_ctl.rc_hpts_flags |= PACE_TMR_RXT; 607 if (tp->t_srtt == 0) 608 tov = BBR_INITIAL_RTO; 609 else 610 tov = ((uint64_t)(TICKS_2_USEC(tp->t_srtt) + 611 ((uint64_t)TICKS_2_USEC(tp->t_rttvar) * (uint64_t)4)) >> TCP_RTT_SHIFT); 612 if (tp->t_rxtshift) 613 tov *= tcp_backoff[tp->t_rxtshift]; 614 if (tov > time_since_sent) 615 tov -= time_since_sent; 616 else 617 tov = bbr->r_ctl.rc_min_to; 618 TCPT_RANGESET_NOSLOP(to, tov, 619 (bbr->r_ctl.rc_min_rto_ms * MS_IN_USEC), 620 (bbr->rc_max_rto_sec * USECS_IN_SECOND)); 621 bbr_log_timer_var(bbr, 2, cts, 0, srtt, 0, to); 622 return (to); 623 } 624 return (0); 625 } 626 if (rsm->r_flags & BBR_ACKED) { 627 rsm = bbr_find_lowest_rsm(bbr); 628 if (rsm == NULL) { 629 /* No lowest? */ 630 goto activate_rxt; 631 } 632 } 633 /* Convert from ms to usecs */ 634 if (rsm->r_flags & BBR_SACK_PASSED) { 635 if ((tp->t_flags & TF_SENTFIN) && 636 ((tp->snd_max - tp->snd_una) == 1) && 637 (rsm->r_flags & BBR_HAS_FIN)) { 638 /* 639 * We don't start a bbr rack timer if all we have is 640 * a FIN outstanding. 641 */ 642 goto activate_rxt; 643 } 644 srtt = bbr_get_rtt(bbr, BBR_RTT_RACK); 645 thresh = bbr_calc_thresh_rack(bbr, srtt, cts, rsm); 646 idx = rsm->r_rtr_cnt - 1; 647 exp = rsm->r_tim_lastsent[idx] + thresh; 648 if (SEQ_GEQ(exp, cts)) { 649 to = exp - cts; 650 if (to < bbr->r_ctl.rc_min_to) { 651 to = bbr->r_ctl.rc_min_to; 652 } 653 } else { 654 to = bbr->r_ctl.rc_min_to; 655 } 656 } else { 657 /* Ok we need to do a TLP not RACK */ 658 if (bbr->rc_tlp_in_progress != 0) { 659 /* 660 * The previous send was a TLP. 661 */ 662 goto activate_rxt; 663 } 664 rsm = TAILQ_LAST_FAST(&bbr->r_ctl.rc_tmap, bbr_sendmap, r_tnext); 665 if (rsm == NULL) { 666 /* We found no rsm to TLP with. */ 667 goto activate_rxt; 668 } 669 if (rsm->r_flags & BBR_HAS_FIN) { 670 /* If its a FIN we don't do TLP */ 671 rsm = NULL; 672 goto activate_rxt; 673 } 674 time_since_sent = 0; 675 idx = rsm->r_rtr_cnt - 1; 676 if (TSTMP_GEQ(rsm->r_tim_lastsent[idx], bbr->r_ctl.rc_tlp_rxt_last_time)) 677 tstmp_touse = rsm->r_tim_lastsent[idx]; 678 else 679 tstmp_touse = bbr->r_ctl.rc_tlp_rxt_last_time; 680 if (TSTMP_GT(tstmp_touse, cts)) 681 time_since_sent = cts - tstmp_touse; 682 is_tlp_timer = 1; 683 srtt = bbr_get_rtt(bbr, bbr_tlp_type_to_use); 684 thresh = bbr_calc_thresh_tlp(tp, bbr, rsm, srtt, cts); 685 if (thresh > time_since_sent) 686 to = thresh - time_since_sent; 687 else 688 to = bbr->r_ctl.rc_min_to; 689 if (to > (((uint32_t)bbr->rc_max_rto_sec) * USECS_IN_SECOND)) { 690 /* 691 * If the TLP time works out to larger than the max 692 * RTO lets not do TLP.. just RTO. 693 */ 694 goto activate_rxt; 695 } 696 if ((bbr->rc_tlp_rtx_out == 1) && 697 (rsm->r_start == bbr->r_ctl.rc_last_tlp_seq)) { 698 /* 699 * Second retransmit of the same TLP 700 * lets not. 701 */ 702 bbr->rc_tlp_rtx_out = 0; 703 goto activate_rxt; 704 } 705 if (rsm->r_start != bbr->r_ctl.rc_last_tlp_seq) { 706 /* 707 * The tail is no longer the last one I did a probe 708 * on 709 */ 710 bbr->r_ctl.rc_tlp_seg_send_cnt = 0; 711 bbr->r_ctl.rc_last_tlp_seq = rsm->r_start; 712 } 713 } 714 if (is_tlp_timer == 0) { 715 BBR_STAT_INC(bbr_to_arm_rack); 716 bbr->r_ctl.rc_hpts_flags |= PACE_TMR_RACK; 717 } else { 718 bbr_log_timer_var(bbr, 1, cts, time_since_sent, srtt, thresh, to); 719 if (bbr->r_ctl.rc_tlp_seg_send_cnt > bbr_tlp_max_resend) { 720 /* 721 * We have exceeded how many times we can retran the 722 * current TLP timer, switch to the RTO timer. 723 */ 724 goto activate_rxt; 725 } else { 726 BBR_STAT_INC(bbr_to_arm_tlp); 727 bbr->r_ctl.rc_hpts_flags |= PACE_TMR_TLP; 728 } 729 } 730 return (to); 731 } 732 733 static inline int32_t 734 bbr_minseg(struct tcp_bbr *bbr) 735 { 736 return (bbr->r_ctl.rc_pace_min_segs - bbr->rc_last_options); 737 } 738 739 static void 740 bbr_start_hpts_timer(struct tcp_bbr *bbr, struct tcpcb *tp, uint32_t cts, int32_t frm, int32_t slot, uint32_t tot_len) 741 { 742 struct inpcb *inp; 743 struct hpts_diag diag; 744 uint32_t delayed_ack = 0; 745 uint32_t left = 0; 746 uint32_t hpts_timeout; 747 uint8_t stopped; 748 int32_t delay_calc = 0; 749 uint32_t prev_delay = 0; 750 751 inp = tp->t_inpcb; 752 if (inp->inp_in_hpts) { 753 /* A previous call is already set up */ 754 return; 755 } 756 if ((tp->t_state == TCPS_CLOSED) || 757 (tp->t_state == TCPS_LISTEN)) { 758 return; 759 } 760 stopped = bbr->rc_tmr_stopped; 761 if (stopped && TSTMP_GT(bbr->r_ctl.rc_timer_exp, cts)) { 762 left = bbr->r_ctl.rc_timer_exp - cts; 763 } 764 bbr->r_ctl.rc_hpts_flags = 0; 765 bbr->r_ctl.rc_timer_exp = 0; 766 prev_delay = bbr->r_ctl.rc_last_delay_val; 767 if (bbr->r_ctl.rc_last_delay_val && 768 (slot == 0)) { 769 /* 770 * If a previous pacer delay was in place we 771 * are not coming from the output side (where 772 * we calculate a delay, more likely a timer). 773 */ 774 slot = bbr->r_ctl.rc_last_delay_val; 775 if (TSTMP_GT(cts, bbr->rc_pacer_started)) { 776 /* Compensate for time passed */ 777 delay_calc = cts - bbr->rc_pacer_started; 778 if (delay_calc <= slot) 779 slot -= delay_calc; 780 } 781 } 782 /* Do we have early to make up for by pushing out the pacing time? */ 783 if (bbr->r_agg_early_set) { 784 bbr_log_pacing_delay_calc(bbr, 0, bbr->r_ctl.rc_agg_early, cts, slot, 0, bbr->r_agg_early_set, 2); 785 slot += bbr->r_ctl.rc_agg_early; 786 bbr->r_ctl.rc_agg_early = 0; 787 bbr->r_agg_early_set = 0; 788 } 789 /* Are we running a total debt that needs to be compensated for? */ 790 if (bbr->r_ctl.rc_hptsi_agg_delay) { 791 if (slot > bbr->r_ctl.rc_hptsi_agg_delay) { 792 /* We nuke the delay */ 793 slot -= bbr->r_ctl.rc_hptsi_agg_delay; 794 bbr->r_ctl.rc_hptsi_agg_delay = 0; 795 } else { 796 /* We nuke some of the delay, put in a minimal 100usecs */ 797 bbr->r_ctl.rc_hptsi_agg_delay -= slot; 798 bbr->r_ctl.rc_last_delay_val = slot = 100; 799 } 800 } 801 bbr->r_ctl.rc_last_delay_val = slot; 802 hpts_timeout = bbr_timer_start(tp, bbr, cts); 803 if (tp->t_flags & TF_DELACK) { 804 if (bbr->rc_in_persist == 0) { 805 delayed_ack = bbr_delack_time; 806 } else { 807 /* 808 * We are in persists and have 809 * gotten a new data element. 810 */ 811 if (hpts_timeout > bbr_delack_time) { 812 /* 813 * Lets make the persists timer (which acks) 814 * be the smaller of hpts_timeout and bbr_delack_time. 815 */ 816 hpts_timeout = bbr_delack_time; 817 } 818 } 819 } 820 if (delayed_ack && 821 ((hpts_timeout == 0) || 822 (delayed_ack < hpts_timeout))) { 823 /* We need a Delayed ack timer */ 824 bbr->r_ctl.rc_hpts_flags = PACE_TMR_DELACK; 825 hpts_timeout = delayed_ack; 826 } 827 if (slot) { 828 /* Mark that we have a pacing timer up */ 829 BBR_STAT_INC(bbr_paced_segments); 830 bbr->r_ctl.rc_hpts_flags |= PACE_PKT_OUTPUT; 831 } 832 /* 833 * If no timers are going to run and we will fall off thfe hptsi 834 * wheel, we resort to a keep-alive timer if its configured. 835 */ 836 if ((hpts_timeout == 0) && 837 (slot == 0)) { 838 if ((tcp_always_keepalive || inp->inp_socket->so_options & SO_KEEPALIVE) && 839 (tp->t_state <= TCPS_CLOSING)) { 840 /* 841 * Ok we have no timer (persists, rack, tlp, rxt or 842 * del-ack), we don't have segments being paced. So 843 * all that is left is the keepalive timer. 844 */ 845 if (TCPS_HAVEESTABLISHED(tp->t_state)) { 846 hpts_timeout = TICKS_2_USEC(TP_KEEPIDLE(tp)); 847 } else { 848 hpts_timeout = TICKS_2_USEC(TP_KEEPINIT(tp)); 849 } 850 bbr->r_ctl.rc_hpts_flags |= PACE_TMR_KEEP; 851 } 852 } 853 if (left && (stopped & (PACE_TMR_KEEP | PACE_TMR_DELACK)) == 854 (bbr->r_ctl.rc_hpts_flags & PACE_TMR_MASK)) { 855 /* 856 * RACK, TLP, persists and RXT timers all are restartable 857 * based on actions input .. i.e we received a packet (ack 858 * or sack) and that changes things (rw, or snd_una etc). 859 * Thus we can restart them with a new value. For 860 * keep-alive, delayed_ack we keep track of what was left 861 * and restart the timer with a smaller value. 862 */ 863 if (left < hpts_timeout) 864 hpts_timeout = left; 865 } 866 if (bbr->r_ctl.rc_incr_tmrs && slot && 867 (bbr->r_ctl.rc_hpts_flags & (PACE_TMR_TLP|PACE_TMR_RXT))) { 868 /* 869 * If configured to do so, and the timer is either 870 * the TLP or RXT timer, we need to increase the timeout 871 * by the pacing time. Consider the bottleneck at my 872 * machine as an example, we are sending something 873 * to start a TLP on. The last packet won't be emitted 874 * fully until the pacing time (the bottleneck will hold 875 * the data in place). Once the packet is emitted that 876 * is when we want to start waiting for the TLP. This 877 * is most evident with hardware pacing (where the nic 878 * is holding the packet(s) before emitting). But it 879 * can also show up in the network so we do it for all 880 * cases. Technically we would take off one packet from 881 * this extra delay but this is easier and being more 882 * conservative is probably better. 883 */ 884 hpts_timeout += slot; 885 } 886 if (hpts_timeout) { 887 /* 888 * Hack alert for now we can't time-out over 2147 seconds (a 889 * bit more than 35min) 890 */ 891 if (hpts_timeout > 0x7ffffffe) 892 hpts_timeout = 0x7ffffffe; 893 bbr->r_ctl.rc_timer_exp = cts + hpts_timeout; 894 } else 895 bbr->r_ctl.rc_timer_exp = 0; 896 if ((slot) && 897 (bbr->rc_use_google || 898 bbr->output_error_seen || 899 (slot <= hpts_timeout)) ) { 900 /* 901 * Tell LRO that it can queue packets while 902 * we pace. 903 */ 904 bbr->rc_inp->inp_flags2 |= INP_MBUF_QUEUE_READY; 905 if ((bbr->r_ctl.rc_hpts_flags & PACE_TMR_RACK) && 906 (bbr->rc_cwnd_limited == 0)) { 907 /* 908 * If we are not cwnd limited and we 909 * are running a rack timer we put on 910 * the do not disturbe even for sack. 911 */ 912 inp->inp_flags2 |= INP_DONT_SACK_QUEUE; 913 } else 914 inp->inp_flags2 &= ~INP_DONT_SACK_QUEUE; 915 bbr->rc_pacer_started = cts; 916 917 (void)tcp_hpts_insert_diag(tp->t_inpcb, HPTS_USEC_TO_SLOTS(slot), 918 __LINE__, &diag); 919 bbr->rc_timer_first = 0; 920 bbr->bbr_timer_src = frm; 921 bbr_log_to_start(bbr, cts, hpts_timeout, slot, 1); 922 bbr_log_hpts_diag(bbr, cts, &diag); 923 } else if (hpts_timeout) { 924 (void)tcp_hpts_insert_diag(tp->t_inpcb, HPTS_USEC_TO_SLOTS(hpts_timeout), 925 __LINE__, &diag); 926 /* 927 * We add the flag here as well if the slot is set, 928 * since hpts will call in to clear the queue first before 929 * calling the output routine (which does our timers). 930 * We don't want to set the flag if its just a timer 931 * else the arrival of data might (that causes us 932 * to send more) might get delayed. Imagine being 933 * on a keep-alive timer and a request comes in for 934 * more data. 935 */ 936 if (slot) 937 bbr->rc_pacer_started = cts; 938 if ((bbr->r_ctl.rc_hpts_flags & PACE_TMR_RACK) && 939 (bbr->rc_cwnd_limited == 0)) { 940 /* 941 * For a rack timer, don't wake us even 942 * if a sack arrives as long as we are 943 * not cwnd limited. 944 */ 945 bbr->rc_inp->inp_flags2 |= INP_MBUF_QUEUE_READY; 946 inp->inp_flags2 |= INP_DONT_SACK_QUEUE; 947 } else { 948 /* All other timers wake us up */ 949 bbr->rc_inp->inp_flags2 &= ~INP_MBUF_QUEUE_READY; 950 inp->inp_flags2 &= ~INP_DONT_SACK_QUEUE; 951 } 952 bbr->bbr_timer_src = frm; 953 bbr_log_to_start(bbr, cts, hpts_timeout, slot, 0); 954 bbr_log_hpts_diag(bbr, cts, &diag); 955 bbr->rc_timer_first = 1; 956 } 957 bbr->rc_tmr_stopped = 0; 958 bbr_log_type_bbrsnd(bbr, tot_len, slot, delay_calc, cts, frm, prev_delay); 959 } 960 961 static void 962 bbr_timer_audit(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts, struct sockbuf *sb) 963 { 964 /* 965 * We received an ack, and then did not call send or were bounced 966 * out due to the hpts was running. Now a timer is up as well, is it 967 * the right timer? 968 */ 969 struct inpcb *inp; 970 struct bbr_sendmap *rsm; 971 uint32_t hpts_timeout; 972 int tmr_up; 973 974 tmr_up = bbr->r_ctl.rc_hpts_flags & PACE_TMR_MASK; 975 if (bbr->rc_in_persist && (tmr_up == PACE_TMR_PERSIT)) 976 return; 977 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_tmap); 978 if (((rsm == NULL) || (tp->t_state < TCPS_ESTABLISHED)) && 979 (tmr_up == PACE_TMR_RXT)) { 980 /* Should be an RXT */ 981 return; 982 } 983 inp = bbr->rc_inp; 984 if (rsm == NULL) { 985 /* Nothing outstanding? */ 986 if (tp->t_flags & TF_DELACK) { 987 if (tmr_up == PACE_TMR_DELACK) 988 /* 989 * We are supposed to have delayed ack up 990 * and we do 991 */ 992 return; 993 } else if (sbavail(&inp->inp_socket->so_snd) && 994 (tmr_up == PACE_TMR_RXT)) { 995 /* 996 * if we hit enobufs then we would expect the 997 * possiblity of nothing outstanding and the RXT up 998 * (and the hptsi timer). 999 */ 1000 return; 1001 } else if (((tcp_always_keepalive || 1002 inp->inp_socket->so_options & SO_KEEPALIVE) && 1003 (tp->t_state <= TCPS_CLOSING)) && 1004 (tmr_up == PACE_TMR_KEEP) && 1005 (tp->snd_max == tp->snd_una)) { 1006 /* We should have keep alive up and we do */ 1007 return; 1008 } 1009 } 1010 if (rsm && (rsm->r_flags & BBR_SACK_PASSED)) { 1011 if ((tp->t_flags & TF_SENTFIN) && 1012 ((tp->snd_max - tp->snd_una) == 1) && 1013 (rsm->r_flags & BBR_HAS_FIN)) { 1014 /* needs to be a RXT */ 1015 if (tmr_up == PACE_TMR_RXT) 1016 return; 1017 else 1018 goto wrong_timer; 1019 } else if (tmr_up == PACE_TMR_RACK) 1020 return; 1021 else 1022 goto wrong_timer; 1023 } else if (rsm && (tmr_up == PACE_TMR_RACK)) { 1024 /* Rack timer has priority if we have data out */ 1025 return; 1026 } else if (SEQ_GT(tp->snd_max, tp->snd_una) && 1027 ((tmr_up == PACE_TMR_TLP) || 1028 (tmr_up == PACE_TMR_RXT))) { 1029 /* 1030 * Either a TLP or RXT is fine if no sack-passed is in place 1031 * and data is outstanding. 1032 */ 1033 return; 1034 } else if (tmr_up == PACE_TMR_DELACK) { 1035 /* 1036 * If the delayed ack was going to go off before the 1037 * rtx/tlp/rack timer were going to expire, then that would 1038 * be the timer in control. Note we don't check the time 1039 * here trusting the code is correct. 1040 */ 1041 return; 1042 } 1043 if (SEQ_GT(tp->snd_max, tp->snd_una) && 1044 ((tmr_up == PACE_TMR_RXT) || 1045 (tmr_up == PACE_TMR_TLP) || 1046 (tmr_up == PACE_TMR_RACK))) { 1047 /* 1048 * We have outstanding data and 1049 * we *do* have a RACK, TLP or RXT 1050 * timer running. We won't restart 1051 * anything here since thats probably ok we 1052 * will get called with some timer here shortly. 1053 */ 1054 return; 1055 } 1056 /* 1057 * Ok the timer originally started is not what we want now. We will 1058 * force the hpts to be stopped if any, and restart with the slot 1059 * set to what was in the saved slot. 1060 */ 1061 wrong_timer: 1062 if ((bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) == 0) { 1063 if (inp->inp_in_hpts) 1064 tcp_hpts_remove(inp, HPTS_REMOVE_OUTPUT); 1065 bbr_timer_cancel(bbr, __LINE__, cts); 1066 bbr_start_hpts_timer(bbr, tp, cts, 1, bbr->r_ctl.rc_last_delay_val, 1067 0); 1068 } else { 1069 /* 1070 * Output is hptsi so we just need to switch the type of 1071 * timer. We don't bother with keep-alive, since when we 1072 * jump through the output, it will start the keep-alive if 1073 * nothing is sent. 1074 * 1075 * We only need a delayed-ack added and or the hpts_timeout. 1076 */ 1077 hpts_timeout = bbr_timer_start(tp, bbr, cts); 1078 if (tp->t_flags & TF_DELACK) { 1079 if (hpts_timeout == 0) { 1080 hpts_timeout = bbr_delack_time; 1081 bbr->r_ctl.rc_hpts_flags = PACE_TMR_DELACK; 1082 } 1083 else if (hpts_timeout > bbr_delack_time) { 1084 hpts_timeout = bbr_delack_time; 1085 bbr->r_ctl.rc_hpts_flags = PACE_TMR_DELACK; 1086 } 1087 } 1088 if (hpts_timeout) { 1089 if (hpts_timeout > 0x7ffffffe) 1090 hpts_timeout = 0x7ffffffe; 1091 bbr->r_ctl.rc_timer_exp = cts + hpts_timeout; 1092 } 1093 } 1094 } 1095 1096 int32_t bbr_clear_lost = 0; 1097 1098 /* 1099 * Considers the two time values now (cts) and earlier. 1100 * If cts is smaller than earlier, we could have 1101 * had a sequence wrap (our counter wraps every 1102 * 70 min or so) or it could be just clock skew 1103 * getting us two differnt time values. Clock skew 1104 * will show up within 10ms or so. So in such 1105 * a case (where cts is behind earlier time by 1106 * less than 10ms) we return 0. Otherwise we 1107 * return the true difference between them. 1108 */ 1109 static inline uint32_t 1110 bbr_calc_time(uint32_t cts, uint32_t earlier_time) { 1111 /* 1112 * Given two timestamps, the current time stamp cts, and some other 1113 * time-stamp taken in theory earlier return the difference. The 1114 * trick is here sometimes locking will get the other timestamp 1115 * after the cts. If this occurs we need to return 0. 1116 */ 1117 if (TSTMP_GEQ(cts, earlier_time)) 1118 return (cts - earlier_time); 1119 /* 1120 * cts is behind earlier_time if its less than 10ms consider it 0. 1121 * If its more than 10ms difference then we had a time wrap. Else 1122 * its just the normal locking foo. I wonder if we should not go to 1123 * 64bit TS and get rid of this issue. 1124 */ 1125 if (TSTMP_GEQ((cts + 10000), earlier_time)) 1126 return (0); 1127 /* 1128 * Ok the time must have wrapped. So we need to answer a large 1129 * amount of time, which the normal subtraction should do. 1130 */ 1131 return (cts - earlier_time); 1132 } 1133 1134 1135 1136 static int 1137 sysctl_bbr_clear_lost(SYSCTL_HANDLER_ARGS) 1138 { 1139 uint32_t stat; 1140 int32_t error; 1141 1142 error = SYSCTL_OUT(req, &bbr_clear_lost, sizeof(uint32_t)); 1143 if (error || req->newptr == NULL) 1144 return error; 1145 1146 error = SYSCTL_IN(req, &stat, sizeof(uint32_t)); 1147 if (error) 1148 return (error); 1149 if (stat == 1) { 1150 #ifdef BBR_INVARIANTS 1151 printf("Clearing BBR lost counters\n"); 1152 #endif 1153 COUNTER_ARRAY_ZERO(bbr_state_lost, BBR_MAX_STAT); 1154 COUNTER_ARRAY_ZERO(bbr_state_time, BBR_MAX_STAT); 1155 COUNTER_ARRAY_ZERO(bbr_state_resend, BBR_MAX_STAT); 1156 } else if (stat == 2) { 1157 #ifdef BBR_INVARIANTS 1158 printf("Clearing BBR option counters\n"); 1159 #endif 1160 COUNTER_ARRAY_ZERO(bbr_opts_arry, BBR_OPTS_SIZE); 1161 } else if (stat == 3) { 1162 #ifdef BBR_INVARIANTS 1163 printf("Clearing BBR stats counters\n"); 1164 #endif 1165 COUNTER_ARRAY_ZERO(bbr_stat_arry, BBR_STAT_SIZE); 1166 } else if (stat == 4) { 1167 #ifdef BBR_INVARIANTS 1168 printf("Clearing BBR out-size counters\n"); 1169 #endif 1170 COUNTER_ARRAY_ZERO(bbr_out_size, TCP_MSS_ACCT_SIZE); 1171 } 1172 bbr_clear_lost = 0; 1173 return (0); 1174 } 1175 1176 static void 1177 bbr_init_sysctls(void) 1178 { 1179 struct sysctl_oid *bbr_probertt; 1180 struct sysctl_oid *bbr_hptsi; 1181 struct sysctl_oid *bbr_measure; 1182 struct sysctl_oid *bbr_cwnd; 1183 struct sysctl_oid *bbr_timeout; 1184 struct sysctl_oid *bbr_states; 1185 struct sysctl_oid *bbr_startup; 1186 struct sysctl_oid *bbr_policer; 1187 1188 /* Probe rtt controls */ 1189 bbr_probertt = SYSCTL_ADD_NODE(&bbr_sysctl_ctx, 1190 SYSCTL_CHILDREN(bbr_sysctl_root), 1191 OID_AUTO, 1192 "probertt", 1193 CTLFLAG_RW, 0, 1194 ""); 1195 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1196 SYSCTL_CHILDREN(bbr_probertt), 1197 OID_AUTO, "gain", CTLFLAG_RW, 1198 &bbr_rttprobe_gain, 192, 1199 "What is the filter gain drop in probe_rtt (0=disable)?"); 1200 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1201 SYSCTL_CHILDREN(bbr_probertt), 1202 OID_AUTO, "cwnd", CTLFLAG_RW, 1203 &bbr_rtt_probe_cwndtarg, 4, 1204 "How many mss's are outstanding during probe-rtt"); 1205 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1206 SYSCTL_CHILDREN(bbr_probertt), 1207 OID_AUTO, "int", CTLFLAG_RW, 1208 &bbr_rtt_probe_limit, 4000000, 1209 "If RTT has not shrank in this many micro-seconds enter probe-rtt"); 1210 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1211 SYSCTL_CHILDREN(bbr_probertt), 1212 OID_AUTO, "mintime", CTLFLAG_RW, 1213 &bbr_rtt_probe_time, 200000, 1214 "How many microseconds in probe-rtt"); 1215 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1216 SYSCTL_CHILDREN(bbr_probertt), 1217 OID_AUTO, "filter_len_sec", CTLFLAG_RW, 1218 &bbr_filter_len_sec, 6, 1219 "How long in seconds does the rttProp filter run?"); 1220 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1221 SYSCTL_CHILDREN(bbr_probertt), 1222 OID_AUTO, "drain_rtt", CTLFLAG_RW, 1223 &bbr_drain_rtt, BBR_SRTT, 1224 "What is the drain rtt to use in probeRTT (rtt_prop=0, rtt_rack=1, rtt_pkt=2, rtt_srtt=3?"); 1225 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1226 SYSCTL_CHILDREN(bbr_probertt), 1227 OID_AUTO, "can_force", CTLFLAG_RW, 1228 &bbr_can_force_probertt, 0, 1229 "If we keep setting new low rtt's but delay going in probe-rtt can we force in??"); 1230 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1231 SYSCTL_CHILDREN(bbr_probertt), 1232 OID_AUTO, "enter_sets_force", CTLFLAG_RW, 1233 &bbr_probertt_sets_rtt, 0, 1234 "In NF mode, do we imitate google_mode and set the rttProp on entry to probe-rtt?"); 1235 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1236 SYSCTL_CHILDREN(bbr_probertt), 1237 OID_AUTO, "can_adjust", CTLFLAG_RW, 1238 &bbr_can_adjust_probertt, 1, 1239 "Can we dynamically adjust the probe-rtt limits and times?"); 1240 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1241 SYSCTL_CHILDREN(bbr_probertt), 1242 OID_AUTO, "is_ratio", CTLFLAG_RW, 1243 &bbr_is_ratio, 0, 1244 "is the limit to filter a ratio?"); 1245 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1246 SYSCTL_CHILDREN(bbr_probertt), 1247 OID_AUTO, "use_cwnd", CTLFLAG_RW, 1248 &bbr_prtt_slam_cwnd, 0, 1249 "Should we set/recover cwnd?"); 1250 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1251 SYSCTL_CHILDREN(bbr_probertt), 1252 OID_AUTO, "can_use_ts", CTLFLAG_RW, 1253 &bbr_can_use_ts_for_rtt, 1, 1254 "Can we use the ms timestamp if available for retransmistted rtt calculations?"); 1255 1256 /* Pacing controls */ 1257 bbr_hptsi = SYSCTL_ADD_NODE(&bbr_sysctl_ctx, 1258 SYSCTL_CHILDREN(bbr_sysctl_root), 1259 OID_AUTO, 1260 "pacing", 1261 CTLFLAG_RW, 0, 1262 ""); 1263 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1264 SYSCTL_CHILDREN(bbr_hptsi), 1265 OID_AUTO, "hw_pacing", CTLFLAG_RW, 1266 &bbr_allow_hdwr_pacing, 1, 1267 "Do we allow hardware pacing?"); 1268 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1269 SYSCTL_CHILDREN(bbr_hptsi), 1270 OID_AUTO, "hw_pacing_limit", CTLFLAG_RW, 1271 &bbr_hardware_pacing_limit, 4000, 1272 "Do we have a limited number of connections for pacing chelsio (0=no limit)?"); 1273 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1274 SYSCTL_CHILDREN(bbr_hptsi), 1275 OID_AUTO, "hw_pacing_adj", CTLFLAG_RW, 1276 &bbr_hdwr_pace_adjust, 2, 1277 "Multiplier to calculated tso size?"); 1278 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1279 SYSCTL_CHILDREN(bbr_hptsi), 1280 OID_AUTO, "hw_pacing_floor", CTLFLAG_RW, 1281 &bbr_hdwr_pace_floor, 1, 1282 "Do we invoke the hardware pacing floor?"); 1283 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1284 SYSCTL_CHILDREN(bbr_hptsi), 1285 OID_AUTO, "hw_pacing_delay_cnt", CTLFLAG_RW, 1286 &bbr_hdwr_pacing_delay_cnt, 10, 1287 "How many packets must be sent after hdwr pacing is enabled"); 1288 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1289 SYSCTL_CHILDREN(bbr_hptsi), 1290 OID_AUTO, "bw_cross", CTLFLAG_RW, 1291 &bbr_cross_over, 3000000, 1292 "What is the point where we cross over to linux like TSO size set"); 1293 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1294 SYSCTL_CHILDREN(bbr_hptsi), 1295 OID_AUTO, "seg_deltarg", CTLFLAG_RW, 1296 &bbr_hptsi_segments_delay_tar, 7000, 1297 "What is the worse case delay target for hptsi < 48Mbp connections"); 1298 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1299 SYSCTL_CHILDREN(bbr_hptsi), 1300 OID_AUTO, "enet_oh", CTLFLAG_RW, 1301 &bbr_include_enet_oh, 0, 1302 "Do we include the ethernet overhead in calculating pacing delay?"); 1303 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1304 SYSCTL_CHILDREN(bbr_hptsi), 1305 OID_AUTO, "ip_oh", CTLFLAG_RW, 1306 &bbr_include_ip_oh, 1, 1307 "Do we include the IP overhead in calculating pacing delay?"); 1308 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1309 SYSCTL_CHILDREN(bbr_hptsi), 1310 OID_AUTO, "tcp_oh", CTLFLAG_RW, 1311 &bbr_include_tcp_oh, 0, 1312 "Do we include the TCP overhead in calculating pacing delay?"); 1313 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1314 SYSCTL_CHILDREN(bbr_hptsi), 1315 OID_AUTO, "google_discount", CTLFLAG_RW, 1316 &bbr_google_discount, 10, 1317 "What is the default google discount percentage wise for pacing (11 = 1.1%%)?"); 1318 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1319 SYSCTL_CHILDREN(bbr_hptsi), 1320 OID_AUTO, "all_get_min", CTLFLAG_RW, 1321 &bbr_all_get_min, 0, 1322 "If you are less than a MSS do you just get the min?"); 1323 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1324 SYSCTL_CHILDREN(bbr_hptsi), 1325 OID_AUTO, "tso_min", CTLFLAG_RW, 1326 &bbr_hptsi_bytes_min, 1460, 1327 "For 0 -> 24Mbps what is floor number of segments for TSO"); 1328 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1329 SYSCTL_CHILDREN(bbr_hptsi), 1330 OID_AUTO, "seg_tso_max", CTLFLAG_RW, 1331 &bbr_hptsi_segments_max, 6, 1332 "For 0 -> 24Mbps what is top number of segments for TSO"); 1333 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1334 SYSCTL_CHILDREN(bbr_hptsi), 1335 OID_AUTO, "seg_floor", CTLFLAG_RW, 1336 &bbr_hptsi_segments_floor, 1, 1337 "Minimum TSO size we will fall too in segments"); 1338 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1339 SYSCTL_CHILDREN(bbr_hptsi), 1340 OID_AUTO, "utter_max", CTLFLAG_RW, 1341 &bbr_hptsi_utter_max, 0, 1342 "The absolute maximum that any pacing (outside of hardware) can be"); 1343 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1344 SYSCTL_CHILDREN(bbr_hptsi), 1345 OID_AUTO, "seg_divisor", CTLFLAG_RW, 1346 &bbr_hptsi_per_second, 100, 1347 "What is the divisor in our hptsi TSO calculation 512Mbps < X > 24Mbps "); 1348 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1349 SYSCTL_CHILDREN(bbr_hptsi), 1350 OID_AUTO, "srtt_mul", CTLFLAG_RW, 1351 &bbr_hptsi_max_mul, 1, 1352 "The multiplier for pace len max"); 1353 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1354 SYSCTL_CHILDREN(bbr_hptsi), 1355 OID_AUTO, "srtt_div", CTLFLAG_RW, 1356 &bbr_hptsi_max_div, 2, 1357 "The divisor for pace len max"); 1358 /* Measurement controls */ 1359 bbr_measure = SYSCTL_ADD_NODE(&bbr_sysctl_ctx, 1360 SYSCTL_CHILDREN(bbr_sysctl_root), 1361 OID_AUTO, 1362 "measure", 1363 CTLFLAG_RW, 0, 1364 "Measurement controls"); 1365 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1366 SYSCTL_CHILDREN(bbr_measure), 1367 OID_AUTO, "min_i_bw", CTLFLAG_RW, 1368 &bbr_initial_bw_bps, 62500, 1369 "Minimum initial b/w in bytes per second"); 1370 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1371 SYSCTL_CHILDREN(bbr_measure), 1372 OID_AUTO, "no_sack_needed", CTLFLAG_RW, 1373 &bbr_sack_not_required, 0, 1374 "Do we allow bbr to run on connections not supporting SACK?"); 1375 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1376 SYSCTL_CHILDREN(bbr_measure), 1377 OID_AUTO, "use_google", CTLFLAG_RW, 1378 &bbr_use_google_algo, 0, 1379 "Use has close to google V1.0 has possible?"); 1380 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1381 SYSCTL_CHILDREN(bbr_measure), 1382 OID_AUTO, "ts_limiting", CTLFLAG_RW, 1383 &bbr_ts_limiting, 1, 1384 "Do we attempt to use the peers timestamp to limit b/w caculations?"); 1385 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1386 SYSCTL_CHILDREN(bbr_measure), 1387 OID_AUTO, "ts_can_raise", CTLFLAG_RW, 1388 &bbr_ts_can_raise, 0, 1389 "Can we raise the b/w via timestamp b/w calculation?"); 1390 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1391 SYSCTL_CHILDREN(bbr_measure), 1392 OID_AUTO, "ts_delta", CTLFLAG_RW, 1393 &bbr_min_usec_delta, 20000, 1394 "How long in usec between ts of our sends in ts validation code?"); 1395 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1396 SYSCTL_CHILDREN(bbr_measure), 1397 OID_AUTO, "ts_peer_delta", CTLFLAG_RW, 1398 &bbr_min_peer_delta, 20, 1399 "What min numerical value should be between the peer deltas?"); 1400 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1401 SYSCTL_CHILDREN(bbr_measure), 1402 OID_AUTO, "ts_delta_percent", CTLFLAG_RW, 1403 &bbr_delta_percent, 150, 1404 "What percentage (150 = 15.0) do we allow variance for?"); 1405 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1406 SYSCTL_CHILDREN(bbr_measure), 1407 OID_AUTO, "min_measure_good_bw", CTLFLAG_RW, 1408 &bbr_min_measurements_req, 1, 1409 "What is the minimum measurment count we need before we switch to our b/w estimate"); 1410 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1411 SYSCTL_CHILDREN(bbr_measure), 1412 OID_AUTO, "min_measure_before_pace", CTLFLAG_RW, 1413 &bbr_no_pacing_until, 4, 1414 "How many pkt-epoch's (0 is off) do we need before pacing is on?"); 1415 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1416 SYSCTL_CHILDREN(bbr_measure), 1417 OID_AUTO, "quanta", CTLFLAG_RW, 1418 &bbr_quanta, 2, 1419 "Extra quanta to add when calculating the target (ID section 4.2.3.2)."); 1420 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1421 SYSCTL_CHILDREN(bbr_measure), 1422 OID_AUTO, "noretran", CTLFLAG_RW, 1423 &bbr_no_retran, 0, 1424 "Should google mode not use retransmission measurements for the b/w estimation?"); 1425 /* State controls */ 1426 bbr_states = SYSCTL_ADD_NODE(&bbr_sysctl_ctx, 1427 SYSCTL_CHILDREN(bbr_sysctl_root), 1428 OID_AUTO, 1429 "states", 1430 CTLFLAG_RW, 0, 1431 "State controls"); 1432 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1433 SYSCTL_CHILDREN(bbr_states), 1434 OID_AUTO, "idle_restart", CTLFLAG_RW, 1435 &bbr_uses_idle_restart, 0, 1436 "Do we use a new special idle_restart state to ramp back up quickly?"); 1437 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1438 SYSCTL_CHILDREN(bbr_states), 1439 OID_AUTO, "idle_restart_threshold", CTLFLAG_RW, 1440 &bbr_idle_restart_threshold, 100000, 1441 "How long must we be idle before we restart??"); 1442 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1443 SYSCTL_CHILDREN(bbr_states), 1444 OID_AUTO, "use_pkt_epoch", CTLFLAG_RW, 1445 &bbr_state_is_pkt_epoch, 0, 1446 "Do we use a pkt-epoch for substate if 0 rttProp?"); 1447 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1448 SYSCTL_CHILDREN(bbr_states), 1449 OID_AUTO, "startup_rtt_gain", CTLFLAG_RW, 1450 &bbr_rtt_gain_thresh, 0, 1451 "What increase in RTT triggers us to stop ignoring no-loss and possibly exit startup?"); 1452 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1453 SYSCTL_CHILDREN(bbr_states), 1454 OID_AUTO, "drain_floor", CTLFLAG_RW, 1455 &bbr_drain_floor, 88, 1456 "What is the lowest we can drain (pg) too?"); 1457 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1458 SYSCTL_CHILDREN(bbr_states), 1459 OID_AUTO, "drain_2_target", CTLFLAG_RW, 1460 &bbr_state_drain_2_tar, 1, 1461 "Do we drain to target in drain substate?"); 1462 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1463 SYSCTL_CHILDREN(bbr_states), 1464 OID_AUTO, "gain_2_target", CTLFLAG_RW, 1465 &bbr_gain_to_target, 1, 1466 "Does probe bw gain to target??"); 1467 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1468 SYSCTL_CHILDREN(bbr_states), 1469 OID_AUTO, "gain_extra_time", CTLFLAG_RW, 1470 &bbr_gain_gets_extra_too, 1, 1471 "Does probe bw gain get the extra time too?"); 1472 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1473 SYSCTL_CHILDREN(bbr_states), 1474 OID_AUTO, "ld_div", CTLFLAG_RW, 1475 &bbr_drain_drop_div, 5, 1476 "Long drain drop divider?"); 1477 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1478 SYSCTL_CHILDREN(bbr_states), 1479 OID_AUTO, "ld_mul", CTLFLAG_RW, 1480 &bbr_drain_drop_mul, 4, 1481 "Long drain drop multiplier?"); 1482 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1483 SYSCTL_CHILDREN(bbr_states), 1484 OID_AUTO, "rand_ot_disc", CTLFLAG_RW, 1485 &bbr_rand_ot, 50, 1486 "Random discount of the ot?"); 1487 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1488 SYSCTL_CHILDREN(bbr_states), 1489 OID_AUTO, "dr_filter_life", CTLFLAG_RW, 1490 &bbr_num_pktepo_for_del_limit, BBR_NUM_RTTS_FOR_DEL_LIMIT, 1491 "How many packet-epochs does the b/w delivery rate last?"); 1492 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1493 SYSCTL_CHILDREN(bbr_states), 1494 OID_AUTO, "subdrain_applimited", CTLFLAG_RW, 1495 &bbr_sub_drain_app_limit, 0, 1496 "Does our sub-state drain invoke app limited if its long?"); 1497 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1498 SYSCTL_CHILDREN(bbr_states), 1499 OID_AUTO, "use_cwnd_subdrain", CTLFLAG_RW, 1500 &bbr_sub_drain_slam_cwnd, 0, 1501 "Should we set/recover cwnd for sub-state drain?"); 1502 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1503 SYSCTL_CHILDREN(bbr_states), 1504 OID_AUTO, "use_cwnd_maindrain", CTLFLAG_RW, 1505 &bbr_slam_cwnd_in_main_drain, 0, 1506 "Should we set/recover cwnd for main-state drain?"); 1507 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1508 SYSCTL_CHILDREN(bbr_states), 1509 OID_AUTO, "google_gets_earlyout", CTLFLAG_RW, 1510 &google_allow_early_out, 1, 1511 "Should we allow google probe-bw/drain to exit early at flight target?"); 1512 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1513 SYSCTL_CHILDREN(bbr_states), 1514 OID_AUTO, "google_exit_loss", CTLFLAG_RW, 1515 &google_consider_lost, 1, 1516 "Should we have losses exit gain of probebw in google mode??"); 1517 /* Startup controls */ 1518 bbr_startup = SYSCTL_ADD_NODE(&bbr_sysctl_ctx, 1519 SYSCTL_CHILDREN(bbr_sysctl_root), 1520 OID_AUTO, 1521 "startup", 1522 CTLFLAG_RW, 0, 1523 "Startup controls"); 1524 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1525 SYSCTL_CHILDREN(bbr_startup), 1526 OID_AUTO, "cheat_iwnd", CTLFLAG_RW, 1527 &bbr_sends_full_iwnd, 1, 1528 "Do we not pace but burst out initial windows has our TSO size?"); 1529 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1530 SYSCTL_CHILDREN(bbr_startup), 1531 OID_AUTO, "loss_threshold", CTLFLAG_RW, 1532 &bbr_startup_loss_thresh, 2000, 1533 "In startup what is the loss threshold in a pe that will exit us from startup?"); 1534 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1535 SYSCTL_CHILDREN(bbr_startup), 1536 OID_AUTO, "use_lowerpg", CTLFLAG_RW, 1537 &bbr_use_lower_gain_in_startup, 1, 1538 "Should we use a lower hptsi gain if we see loss in startup?"); 1539 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1540 SYSCTL_CHILDREN(bbr_startup), 1541 OID_AUTO, "gain", CTLFLAG_RW, 1542 &bbr_start_exit, 25, 1543 "What gain percent do we need to see to stay in startup??"); 1544 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1545 SYSCTL_CHILDREN(bbr_startup), 1546 OID_AUTO, "low_gain", CTLFLAG_RW, 1547 &bbr_low_start_exit, 15, 1548 "What gain percent do we need to see to stay in the lower gain startup??"); 1549 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1550 SYSCTL_CHILDREN(bbr_startup), 1551 OID_AUTO, "loss_exit", CTLFLAG_RW, 1552 &bbr_exit_startup_at_loss, 1, 1553 "Should we exit startup at loss in an epoch if we are not gaining?"); 1554 /* CWND controls */ 1555 bbr_cwnd = SYSCTL_ADD_NODE(&bbr_sysctl_ctx, 1556 SYSCTL_CHILDREN(bbr_sysctl_root), 1557 OID_AUTO, 1558 "cwnd", 1559 CTLFLAG_RW, 0, 1560 "Cwnd controls"); 1561 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1562 SYSCTL_CHILDREN(bbr_cwnd), 1563 OID_AUTO, "tar_rtt", CTLFLAG_RW, 1564 &bbr_cwndtarget_rtt_touse, 0, 1565 "Target cwnd rtt measurment to use (0=rtt_prop, 1=rtt_rack, 2=pkt_rtt, 3=srtt)?"); 1566 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1567 SYSCTL_CHILDREN(bbr_cwnd), 1568 OID_AUTO, "may_shrink", CTLFLAG_RW, 1569 &bbr_cwnd_may_shrink, 0, 1570 "Can the cwnd shrink if it would grow to more than the target?"); 1571 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1572 SYSCTL_CHILDREN(bbr_cwnd), 1573 OID_AUTO, "max_target_limit", CTLFLAG_RW, 1574 &bbr_target_cwnd_mult_limit, 8, 1575 "Do we limit the cwnd to some multiple of the cwnd target if cwnd can't shrink 0=no?"); 1576 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1577 SYSCTL_CHILDREN(bbr_cwnd), 1578 OID_AUTO, "highspeed_min", CTLFLAG_RW, 1579 &bbr_cwnd_min_val_hs, BBR_HIGHSPEED_NUM_MSS, 1580 "What is the high-speed min cwnd (rttProp under 1ms)"); 1581 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1582 SYSCTL_CHILDREN(bbr_cwnd), 1583 OID_AUTO, "lowspeed_min", CTLFLAG_RW, 1584 &bbr_cwnd_min_val, BBR_PROBERTT_NUM_MSS, 1585 "What is the min cwnd (rttProp > 1ms)"); 1586 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1587 SYSCTL_CHILDREN(bbr_cwnd), 1588 OID_AUTO, "initwin", CTLFLAG_RW, 1589 &bbr_def_init_win, 10, 1590 "What is the BBR initial window, if 0 use tcp version"); 1591 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1592 SYSCTL_CHILDREN(bbr_cwnd), 1593 OID_AUTO, "do_loss_red", CTLFLAG_RW, 1594 &bbr_do_red, 600, 1595 "Do we reduce the b/w at exit from recovery based on ratio of prop/srtt (800=80.0, 0=off)?"); 1596 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1597 SYSCTL_CHILDREN(bbr_cwnd), 1598 OID_AUTO, "red_scale", CTLFLAG_RW, 1599 &bbr_red_scale, 20000, 1600 "What RTT do we scale with?"); 1601 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1602 SYSCTL_CHILDREN(bbr_cwnd), 1603 OID_AUTO, "red_growslow", CTLFLAG_RW, 1604 &bbr_red_growth_restrict, 1, 1605 "Do we restrict cwnd growth for whats in flight?"); 1606 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1607 SYSCTL_CHILDREN(bbr_cwnd), 1608 OID_AUTO, "red_div", CTLFLAG_RW, 1609 &bbr_red_div, 2, 1610 "If we reduce whats the divisor?"); 1611 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1612 SYSCTL_CHILDREN(bbr_cwnd), 1613 OID_AUTO, "red_mul", CTLFLAG_RW, 1614 &bbr_red_mul, 1, 1615 "If we reduce whats the mulitiplier?"); 1616 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1617 SYSCTL_CHILDREN(bbr_cwnd), 1618 OID_AUTO, "target_is_unit", CTLFLAG_RW, 1619 &bbr_target_is_bbunit, 0, 1620 "Is the state target the pacing_gain or BBR_UNIT?"); 1621 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1622 SYSCTL_CHILDREN(bbr_cwnd), 1623 OID_AUTO, "drop_limit", CTLFLAG_RW, 1624 &bbr_drop_limit, 0, 1625 "Number of segments limit for drop (0=use min_cwnd w/flight)?"); 1626 1627 /* Timeout controls */ 1628 bbr_timeout = SYSCTL_ADD_NODE(&bbr_sysctl_ctx, 1629 SYSCTL_CHILDREN(bbr_sysctl_root), 1630 OID_AUTO, 1631 "timeout", 1632 CTLFLAG_RW, 0, 1633 "Time out controls"); 1634 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1635 SYSCTL_CHILDREN(bbr_timeout), 1636 OID_AUTO, "delack", CTLFLAG_RW, 1637 &bbr_delack_time, 100000, 1638 "BBR's delayed ack time"); 1639 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1640 SYSCTL_CHILDREN(bbr_timeout), 1641 OID_AUTO, "tlp_uses", CTLFLAG_RW, 1642 &bbr_tlp_type_to_use, 3, 1643 "RTT that TLP uses in its calculations, 0=rttProp, 1=Rack_rtt, 2=pkt_rtt and 3=srtt"); 1644 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1645 SYSCTL_CHILDREN(bbr_timeout), 1646 OID_AUTO, "persmin", CTLFLAG_RW, 1647 &bbr_persist_min, 250000, 1648 "What is the minimum time in microseconds between persists"); 1649 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1650 SYSCTL_CHILDREN(bbr_timeout), 1651 OID_AUTO, "persmax", CTLFLAG_RW, 1652 &bbr_persist_max, 1000000, 1653 "What is the largest delay in microseconds between persists"); 1654 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1655 SYSCTL_CHILDREN(bbr_timeout), 1656 OID_AUTO, "tlp_minto", CTLFLAG_RW, 1657 &bbr_tlp_min, 10000, 1658 "TLP Min timeout in usecs"); 1659 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1660 SYSCTL_CHILDREN(bbr_timeout), 1661 OID_AUTO, "tlp_dack_time", CTLFLAG_RW, 1662 &bbr_delayed_ack_time, 200000, 1663 "TLP delayed ack compensation value"); 1664 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1665 SYSCTL_CHILDREN(bbr_sysctl_root), 1666 OID_AUTO, "minrto", CTLFLAG_RW, 1667 &bbr_rto_min_ms, 30, 1668 "Minimum RTO in ms"); 1669 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1670 SYSCTL_CHILDREN(bbr_timeout), 1671 OID_AUTO, "maxrto", CTLFLAG_RW, 1672 &bbr_rto_max_sec, 4, 1673 "Maxiumum RTO in seconds -- should be at least as large as min_rto"); 1674 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1675 SYSCTL_CHILDREN(bbr_timeout), 1676 OID_AUTO, "tlp_retry", CTLFLAG_RW, 1677 &bbr_tlp_max_resend, 2, 1678 "How many times does TLP retry a single segment or multiple with no ACK"); 1679 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1680 SYSCTL_CHILDREN(bbr_timeout), 1681 OID_AUTO, "minto", CTLFLAG_RW, 1682 &bbr_min_to, 1000, 1683 "Minimum rack timeout in useconds"); 1684 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1685 SYSCTL_CHILDREN(bbr_timeout), 1686 OID_AUTO, "pktdelay", CTLFLAG_RW, 1687 &bbr_pkt_delay, 1000, 1688 "Extra RACK time (in useconds) besides reordering thresh"); 1689 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1690 SYSCTL_CHILDREN(bbr_timeout), 1691 OID_AUTO, "incr_tmrs", CTLFLAG_RW, 1692 &bbr_incr_timers, 1, 1693 "Increase the RXT/TLP timer by the pacing time used?"); 1694 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1695 SYSCTL_CHILDREN(bbr_timeout), 1696 OID_AUTO, "rxtmark_sackpassed", CTLFLAG_RW, 1697 &bbr_marks_rxt_sack_passed, 0, 1698 "Mark sack passed on all those not ack'd when a RXT hits?"); 1699 /* Policer controls */ 1700 bbr_policer = SYSCTL_ADD_NODE(&bbr_sysctl_ctx, 1701 SYSCTL_CHILDREN(bbr_sysctl_root), 1702 OID_AUTO, 1703 "policer", 1704 CTLFLAG_RW, 0, 1705 "Policer controls"); 1706 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1707 SYSCTL_CHILDREN(bbr_policer), 1708 OID_AUTO, "detect_enable", CTLFLAG_RW, 1709 &bbr_policer_detection_enabled, 1, 1710 "Is policer detection enabled??"); 1711 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1712 SYSCTL_CHILDREN(bbr_policer), 1713 OID_AUTO, "min_pes", CTLFLAG_RW, 1714 &bbr_lt_intvl_min_rtts, 4, 1715 "Minimum number of PE's?"); 1716 SYSCTL_ADD_U64(&bbr_sysctl_ctx, 1717 SYSCTL_CHILDREN(bbr_policer), 1718 OID_AUTO, "bwdiff", CTLFLAG_RW, 1719 &bbr_lt_bw_diff, (4000/8), 1720 "Minimal bw diff?"); 1721 SYSCTL_ADD_U64(&bbr_sysctl_ctx, 1722 SYSCTL_CHILDREN(bbr_policer), 1723 OID_AUTO, "bwratio", CTLFLAG_RW, 1724 &bbr_lt_bw_ratio, 8, 1725 "Minimal bw diff?"); 1726 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1727 SYSCTL_CHILDREN(bbr_policer), 1728 OID_AUTO, "from_rack_rxt", CTLFLAG_RW, 1729 &bbr_policer_call_from_rack_to, 0, 1730 "Do we call the policer detection code from a rack-timeout?"); 1731 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1732 SYSCTL_CHILDREN(bbr_policer), 1733 OID_AUTO, "false_postive", CTLFLAG_RW, 1734 &bbr_lt_intvl_fp, 0, 1735 "What packet epoch do we do false-postive detection at (0=no)?"); 1736 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1737 SYSCTL_CHILDREN(bbr_policer), 1738 OID_AUTO, "loss_thresh", CTLFLAG_RW, 1739 &bbr_lt_loss_thresh, 196, 1740 "Loss threshold 196 = 19.6%?"); 1741 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1742 SYSCTL_CHILDREN(bbr_policer), 1743 OID_AUTO, "false_postive_thresh", CTLFLAG_RW, 1744 &bbr_lt_fd_thresh, 100, 1745 "What percentage is the false detection threshold (150=15.0)?"); 1746 /* All the rest */ 1747 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1748 SYSCTL_CHILDREN(bbr_sysctl_root), 1749 OID_AUTO, "cheat_rxt", CTLFLAG_RW, 1750 &bbr_use_rack_resend_cheat, 0, 1751 "Do we burst 1ms between sends on retransmissions (like rack)?"); 1752 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1753 SYSCTL_CHILDREN(bbr_sysctl_root), 1754 OID_AUTO, "error_paceout", CTLFLAG_RW, 1755 &bbr_error_base_paceout, 10000, 1756 "When we hit an error what is the min to pace out in usec's?"); 1757 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1758 SYSCTL_CHILDREN(bbr_sysctl_root), 1759 OID_AUTO, "kill_paceout", CTLFLAG_RW, 1760 &bbr_max_net_error_cnt, 10, 1761 "When we hit this many errors in a row, kill the session?"); 1762 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1763 SYSCTL_CHILDREN(bbr_sysctl_root), 1764 OID_AUTO, "data_after_close", CTLFLAG_RW, 1765 &bbr_ignore_data_after_close, 1, 1766 "Do we hold off sending a RST until all pending data is ack'd"); 1767 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1768 SYSCTL_CHILDREN(bbr_sysctl_root), 1769 OID_AUTO, "resend_use_tso", CTLFLAG_RW, 1770 &bbr_resends_use_tso, 0, 1771 "Can resends use TSO?"); 1772 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1773 SYSCTL_CHILDREN(bbr_sysctl_root), 1774 OID_AUTO, "sblklimit", CTLFLAG_RW, 1775 &bbr_sack_block_limit, 128, 1776 "When do we start ignoring small sack blocks"); 1777 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1778 SYSCTL_CHILDREN(bbr_sysctl_root), 1779 OID_AUTO, "bb_verbose", CTLFLAG_RW, 1780 &bbr_verbose_logging, 0, 1781 "Should BBR black box logging be verbose"); 1782 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1783 SYSCTL_CHILDREN(bbr_sysctl_root), 1784 OID_AUTO, "reorder_thresh", CTLFLAG_RW, 1785 &bbr_reorder_thresh, 2, 1786 "What factor for rack will be added when seeing reordering (shift right)"); 1787 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1788 SYSCTL_CHILDREN(bbr_sysctl_root), 1789 OID_AUTO, "reorder_fade", CTLFLAG_RW, 1790 &bbr_reorder_fade, 0, 1791 "Does reorder detection fade, if so how many ms (0 means never)"); 1792 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1793 SYSCTL_CHILDREN(bbr_sysctl_root), 1794 OID_AUTO, "rtt_tlp_thresh", CTLFLAG_RW, 1795 &bbr_tlp_thresh, 1, 1796 "what divisor for TLP rtt/retran will be added (1=rtt, 2=1/2 rtt etc)"); 1797 /* Stats and counters */ 1798 /* The pacing counters for hdwr/software can't be in the array */ 1799 bbr_nohdwr_pacing_enobuf = counter_u64_alloc(M_WAITOK); 1800 bbr_hdwr_pacing_enobuf = counter_u64_alloc(M_WAITOK); 1801 SYSCTL_ADD_COUNTER_U64(&bbr_sysctl_ctx, 1802 SYSCTL_CHILDREN(bbr_sysctl_root), 1803 OID_AUTO, "enob_hdwr_pacing", CTLFLAG_RD, 1804 &bbr_hdwr_pacing_enobuf, 1805 "Total number of enobufs for hardware paced flows"); 1806 SYSCTL_ADD_COUNTER_U64(&bbr_sysctl_ctx, 1807 SYSCTL_CHILDREN(bbr_sysctl_root), 1808 OID_AUTO, "enob_no_hdwr_pacing", CTLFLAG_RD, 1809 &bbr_nohdwr_pacing_enobuf, 1810 "Total number of enobufs for non-hardware paced flows"); 1811 1812 1813 bbr_flows_whdwr_pacing = counter_u64_alloc(M_WAITOK); 1814 SYSCTL_ADD_COUNTER_U64(&bbr_sysctl_ctx, 1815 SYSCTL_CHILDREN(bbr_sysctl_root), 1816 OID_AUTO, "hdwr_pacing", CTLFLAG_RD, 1817 &bbr_flows_whdwr_pacing, 1818 "Total number of hardware paced flows"); 1819 bbr_flows_nohdwr_pacing = counter_u64_alloc(M_WAITOK); 1820 SYSCTL_ADD_COUNTER_U64(&bbr_sysctl_ctx, 1821 SYSCTL_CHILDREN(bbr_sysctl_root), 1822 OID_AUTO, "software_pacing", CTLFLAG_RD, 1823 &bbr_flows_nohdwr_pacing, 1824 "Total number of software paced flows"); 1825 COUNTER_ARRAY_ALLOC(bbr_stat_arry, BBR_STAT_SIZE, M_WAITOK); 1826 SYSCTL_ADD_COUNTER_U64_ARRAY(&bbr_sysctl_ctx, SYSCTL_CHILDREN(bbr_sysctl_root), 1827 OID_AUTO, "stats", CTLFLAG_RD, 1828 bbr_stat_arry, BBR_STAT_SIZE, "BBR Stats"); 1829 COUNTER_ARRAY_ALLOC(bbr_opts_arry, BBR_OPTS_SIZE, M_WAITOK); 1830 SYSCTL_ADD_COUNTER_U64_ARRAY(&bbr_sysctl_ctx, SYSCTL_CHILDREN(bbr_sysctl_root), 1831 OID_AUTO, "opts", CTLFLAG_RD, 1832 bbr_opts_arry, BBR_OPTS_SIZE, "BBR Option Stats"); 1833 COUNTER_ARRAY_ALLOC(bbr_state_lost, BBR_MAX_STAT, M_WAITOK); 1834 SYSCTL_ADD_COUNTER_U64_ARRAY(&bbr_sysctl_ctx, SYSCTL_CHILDREN(bbr_sysctl_root), 1835 OID_AUTO, "lost", CTLFLAG_RD, 1836 bbr_state_lost, BBR_MAX_STAT, "Stats of when losses occur"); 1837 COUNTER_ARRAY_ALLOC(bbr_state_resend, BBR_MAX_STAT, M_WAITOK); 1838 SYSCTL_ADD_COUNTER_U64_ARRAY(&bbr_sysctl_ctx, SYSCTL_CHILDREN(bbr_sysctl_root), 1839 OID_AUTO, "stateresend", CTLFLAG_RD, 1840 bbr_state_resend, BBR_MAX_STAT, "Stats of what states resend"); 1841 COUNTER_ARRAY_ALLOC(bbr_state_time, BBR_MAX_STAT, M_WAITOK); 1842 SYSCTL_ADD_COUNTER_U64_ARRAY(&bbr_sysctl_ctx, SYSCTL_CHILDREN(bbr_sysctl_root), 1843 OID_AUTO, "statetime", CTLFLAG_RD, 1844 bbr_state_time, BBR_MAX_STAT, "Stats of time spent in the states"); 1845 COUNTER_ARRAY_ALLOC(bbr_out_size, TCP_MSS_ACCT_SIZE, M_WAITOK); 1846 SYSCTL_ADD_COUNTER_U64_ARRAY(&bbr_sysctl_ctx, SYSCTL_CHILDREN(bbr_sysctl_root), 1847 OID_AUTO, "outsize", CTLFLAG_RD, 1848 bbr_out_size, TCP_MSS_ACCT_SIZE, "Size of output calls"); 1849 SYSCTL_ADD_PROC(&bbr_sysctl_ctx, 1850 SYSCTL_CHILDREN(bbr_sysctl_root), 1851 OID_AUTO, "clrlost", CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_MPSAFE, 1852 &bbr_clear_lost, 0, sysctl_bbr_clear_lost, "IU", "Clear lost counters"); 1853 } 1854 1855 static inline int32_t 1856 bbr_progress_timeout_check(struct tcp_bbr *bbr) 1857 { 1858 if (bbr->rc_tp->t_maxunacktime && bbr->rc_tp->t_acktime && 1859 TSTMP_GT(ticks, bbr->rc_tp->t_acktime)) { 1860 if ((((uint32_t)ticks - bbr->rc_tp->t_acktime)) >= bbr->rc_tp->t_maxunacktime) { 1861 /* 1862 * There is an assumption here that the caller will 1863 * drop the connection, so we increment the 1864 * statistics. 1865 */ 1866 bbr_log_progress_event(bbr, bbr->rc_tp, ticks, PROGRESS_DROP, __LINE__); 1867 BBR_STAT_INC(bbr_progress_drops); 1868 #ifdef NETFLIX_STATS 1869 TCPSTAT_INC(tcps_progdrops); 1870 #endif 1871 return (1); 1872 } 1873 } 1874 return (0); 1875 } 1876 1877 static void 1878 bbr_counter_destroy(void) 1879 { 1880 COUNTER_ARRAY_FREE(bbr_stat_arry, BBR_STAT_SIZE); 1881 COUNTER_ARRAY_FREE(bbr_opts_arry, BBR_OPTS_SIZE); 1882 COUNTER_ARRAY_FREE(bbr_out_size, TCP_MSS_ACCT_SIZE); 1883 COUNTER_ARRAY_FREE(bbr_state_lost, BBR_MAX_STAT); 1884 COUNTER_ARRAY_FREE(bbr_state_time, BBR_MAX_STAT); 1885 COUNTER_ARRAY_FREE(bbr_state_resend, BBR_MAX_STAT); 1886 counter_u64_free(bbr_flows_whdwr_pacing); 1887 counter_u64_free(bbr_flows_nohdwr_pacing); 1888 1889 } 1890 1891 static __inline void 1892 bbr_fill_in_logging_data(struct tcp_bbr *bbr, struct tcp_log_bbr *l, uint32_t cts) 1893 { 1894 memset(l, 0, sizeof(union tcp_log_stackspecific)); 1895 l->cur_del_rate = bbr->r_ctl.rc_bbr_cur_del_rate; 1896 l->delRate = get_filter_value(&bbr->r_ctl.rc_delrate); 1897 l->rttProp = get_filter_value_small(&bbr->r_ctl.rc_rttprop); 1898 l->bw_inuse = bbr_get_bw(bbr); 1899 l->inflight = ctf_flight_size(bbr->rc_tp, 1900 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 1901 l->applimited = bbr->r_ctl.r_app_limited_until; 1902 l->delivered = bbr->r_ctl.rc_delivered; 1903 l->timeStamp = cts; 1904 l->lost = bbr->r_ctl.rc_lost; 1905 l->bbr_state = bbr->rc_bbr_state; 1906 l->bbr_substate = bbr_state_val(bbr); 1907 l->epoch = bbr->r_ctl.rc_rtt_epoch; 1908 l->lt_epoch = bbr->r_ctl.rc_lt_epoch; 1909 l->pacing_gain = bbr->r_ctl.rc_bbr_hptsi_gain; 1910 l->cwnd_gain = bbr->r_ctl.rc_bbr_cwnd_gain; 1911 l->inhpts = bbr->rc_inp->inp_in_hpts; 1912 l->ininput = bbr->rc_inp->inp_in_input; 1913 l->use_lt_bw = bbr->rc_lt_use_bw; 1914 l->pkts_out = bbr->r_ctl.rc_flight_at_input; 1915 l->pkt_epoch = bbr->r_ctl.rc_pkt_epoch; 1916 } 1917 1918 static void 1919 bbr_log_type_bw_reduce(struct tcp_bbr *bbr, int reason) 1920 { 1921 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 1922 union tcp_log_stackspecific log; 1923 1924 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime); 1925 log.u_bbr.flex1 = 0; 1926 log.u_bbr.flex2 = 0; 1927 log.u_bbr.flex5 = 0; 1928 log.u_bbr.flex3 = 0; 1929 log.u_bbr.flex4 = bbr->r_ctl.rc_pkt_epoch_loss_rate; 1930 log.u_bbr.flex7 = reason; 1931 log.u_bbr.flex6 = bbr->r_ctl.rc_bbr_enters_probertt; 1932 log.u_bbr.flex8 = 0; 1933 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 1934 &bbr->rc_inp->inp_socket->so_rcv, 1935 &bbr->rc_inp->inp_socket->so_snd, 1936 BBR_LOG_BW_RED_EV, 0, 1937 0, &log, false, &bbr->rc_tv); 1938 } 1939 } 1940 1941 static void 1942 bbr_log_type_rwnd_collapse(struct tcp_bbr *bbr, int seq, int mode, uint32_t count) 1943 { 1944 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 1945 union tcp_log_stackspecific log; 1946 1947 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime); 1948 log.u_bbr.flex1 = seq; 1949 log.u_bbr.flex2 = count; 1950 log.u_bbr.flex8 = mode; 1951 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 1952 &bbr->rc_inp->inp_socket->so_rcv, 1953 &bbr->rc_inp->inp_socket->so_snd, 1954 BBR_LOG_LOWGAIN, 0, 1955 0, &log, false, &bbr->rc_tv); 1956 } 1957 } 1958 1959 1960 1961 static void 1962 bbr_log_type_just_return(struct tcp_bbr *bbr, uint32_t cts, uint32_t tlen, uint8_t hpts_calling, 1963 uint8_t reason, uint32_t p_maxseg, int len) 1964 { 1965 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 1966 union tcp_log_stackspecific log; 1967 1968 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 1969 log.u_bbr.flex1 = p_maxseg; 1970 log.u_bbr.flex2 = bbr->r_ctl.rc_hpts_flags; 1971 log.u_bbr.flex3 = bbr->r_ctl.rc_timer_exp; 1972 log.u_bbr.flex4 = reason; 1973 log.u_bbr.flex5 = bbr->rc_in_persist; 1974 log.u_bbr.flex6 = bbr->r_ctl.rc_last_delay_val; 1975 log.u_bbr.flex7 = p_maxseg; 1976 log.u_bbr.flex8 = bbr->rc_in_persist; 1977 log.u_bbr.pkts_out = 0; 1978 log.u_bbr.applimited = len; 1979 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 1980 &bbr->rc_inp->inp_socket->so_rcv, 1981 &bbr->rc_inp->inp_socket->so_snd, 1982 BBR_LOG_JUSTRET, 0, 1983 tlen, &log, false, &bbr->rc_tv); 1984 } 1985 } 1986 1987 1988 static void 1989 bbr_log_type_enter_rec(struct tcp_bbr *bbr, uint32_t seq) 1990 { 1991 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 1992 union tcp_log_stackspecific log; 1993 1994 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime); 1995 log.u_bbr.flex1 = seq; 1996 log.u_bbr.flex2 = bbr->r_ctl.rc_cwnd_on_ent; 1997 log.u_bbr.flex3 = bbr->r_ctl.rc_recovery_start; 1998 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 1999 &bbr->rc_inp->inp_socket->so_rcv, 2000 &bbr->rc_inp->inp_socket->so_snd, 2001 BBR_LOG_ENTREC, 0, 2002 0, &log, false, &bbr->rc_tv); 2003 } 2004 } 2005 2006 static void 2007 bbr_log_msgsize_fail(struct tcp_bbr *bbr, struct tcpcb *tp, uint32_t len, uint32_t maxseg, uint32_t mtu, int32_t csum_flags, int32_t tso, uint32_t cts) 2008 { 2009 if (tp->t_logstate != TCP_LOG_STATE_OFF) { 2010 union tcp_log_stackspecific log; 2011 2012 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2013 log.u_bbr.flex1 = tso; 2014 log.u_bbr.flex2 = maxseg; 2015 log.u_bbr.flex3 = mtu; 2016 log.u_bbr.flex4 = csum_flags; 2017 TCP_LOG_EVENTP(tp, NULL, 2018 &bbr->rc_inp->inp_socket->so_rcv, 2019 &bbr->rc_inp->inp_socket->so_snd, 2020 BBR_LOG_MSGSIZE, 0, 2021 0, &log, false, &bbr->rc_tv); 2022 } 2023 } 2024 2025 static void 2026 bbr_log_flowend(struct tcp_bbr *bbr) 2027 { 2028 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2029 union tcp_log_stackspecific log; 2030 struct sockbuf *r, *s; 2031 struct timeval tv; 2032 2033 if (bbr->rc_inp->inp_socket) { 2034 r = &bbr->rc_inp->inp_socket->so_rcv; 2035 s = &bbr->rc_inp->inp_socket->so_snd; 2036 } else { 2037 r = s = NULL; 2038 } 2039 bbr_fill_in_logging_data(bbr, &log.u_bbr, tcp_get_usecs(&tv)); 2040 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2041 r, s, 2042 TCP_LOG_FLOWEND, 0, 2043 0, &log, false, &tv); 2044 } 2045 } 2046 2047 static void 2048 bbr_log_pkt_epoch(struct tcp_bbr *bbr, uint32_t cts, uint32_t line, 2049 uint32_t lost, uint32_t del) 2050 { 2051 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2052 union tcp_log_stackspecific log; 2053 2054 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2055 log.u_bbr.flex1 = lost; 2056 log.u_bbr.flex2 = del; 2057 log.u_bbr.flex3 = bbr->r_ctl.rc_bbr_lastbtlbw; 2058 log.u_bbr.flex4 = bbr->r_ctl.rc_pkt_epoch_rtt; 2059 log.u_bbr.flex5 = bbr->r_ctl.rc_bbr_last_startup_epoch; 2060 log.u_bbr.flex6 = bbr->r_ctl.rc_lost_at_startup; 2061 log.u_bbr.flex7 = line; 2062 log.u_bbr.flex8 = 0; 2063 log.u_bbr.inflight = bbr->r_ctl.r_measurement_count; 2064 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2065 &bbr->rc_inp->inp_socket->so_rcv, 2066 &bbr->rc_inp->inp_socket->so_snd, 2067 BBR_LOG_PKT_EPOCH, 0, 2068 0, &log, false, &bbr->rc_tv); 2069 } 2070 } 2071 2072 static void 2073 bbr_log_time_epoch(struct tcp_bbr *bbr, uint32_t cts, uint32_t line, uint32_t epoch_time) 2074 { 2075 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) { 2076 union tcp_log_stackspecific log; 2077 2078 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2079 log.u_bbr.flex1 = bbr->r_ctl.rc_lost; 2080 log.u_bbr.flex2 = bbr->rc_inp->inp_socket->so_snd.sb_lowat; 2081 log.u_bbr.flex3 = bbr->rc_inp->inp_socket->so_snd.sb_hiwat; 2082 log.u_bbr.flex7 = line; 2083 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2084 &bbr->rc_inp->inp_socket->so_rcv, 2085 &bbr->rc_inp->inp_socket->so_snd, 2086 BBR_LOG_TIME_EPOCH, 0, 2087 0, &log, false, &bbr->rc_tv); 2088 } 2089 } 2090 2091 static void 2092 bbr_log_set_of_state_target(struct tcp_bbr *bbr, uint32_t new_tar, int line, int meth) 2093 { 2094 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2095 union tcp_log_stackspecific log; 2096 2097 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime); 2098 log.u_bbr.flex1 = bbr->r_ctl.rc_target_at_state; 2099 log.u_bbr.flex2 = new_tar; 2100 log.u_bbr.flex3 = line; 2101 log.u_bbr.flex4 = bbr->r_ctl.rc_pace_max_segs; 2102 log.u_bbr.flex5 = bbr_quanta; 2103 log.u_bbr.flex6 = bbr->r_ctl.rc_pace_min_segs; 2104 log.u_bbr.flex7 = bbr->rc_last_options; 2105 log.u_bbr.flex8 = meth; 2106 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2107 &bbr->rc_inp->inp_socket->so_rcv, 2108 &bbr->rc_inp->inp_socket->so_snd, 2109 BBR_LOG_STATE_TARGET, 0, 2110 0, &log, false, &bbr->rc_tv); 2111 } 2112 2113 } 2114 2115 static void 2116 bbr_log_type_statechange(struct tcp_bbr *bbr, uint32_t cts, int32_t line) 2117 { 2118 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2119 union tcp_log_stackspecific log; 2120 2121 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2122 log.u_bbr.flex1 = line; 2123 log.u_bbr.flex2 = bbr->r_ctl.rc_rtt_shrinks; 2124 log.u_bbr.flex3 = bbr->r_ctl.rc_probertt_int; 2125 if (bbr_state_is_pkt_epoch) 2126 log.u_bbr.flex4 = bbr_get_rtt(bbr, BBR_RTT_PKTRTT); 2127 else 2128 log.u_bbr.flex4 = bbr_get_rtt(bbr, BBR_RTT_PROP); 2129 log.u_bbr.flex5 = bbr->r_ctl.rc_bbr_last_startup_epoch; 2130 log.u_bbr.flex6 = bbr->r_ctl.rc_lost_at_startup; 2131 log.u_bbr.flex7 = (bbr->r_ctl.rc_target_at_state/1000); 2132 log.u_bbr.lt_epoch = bbr->r_ctl.rc_level_state_extra; 2133 log.u_bbr.pkts_out = bbr->r_ctl.rc_target_at_state; 2134 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2135 &bbr->rc_inp->inp_socket->so_rcv, 2136 &bbr->rc_inp->inp_socket->so_snd, 2137 BBR_LOG_STATE, 0, 2138 0, &log, false, &bbr->rc_tv); 2139 } 2140 } 2141 2142 static void 2143 bbr_log_rtt_shrinks(struct tcp_bbr *bbr, uint32_t cts, uint32_t applied, 2144 uint32_t rtt, uint32_t line, uint8_t reas, uint16_t cond) 2145 { 2146 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2147 union tcp_log_stackspecific log; 2148 2149 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2150 log.u_bbr.flex1 = line; 2151 log.u_bbr.flex2 = bbr->r_ctl.rc_rtt_shrinks; 2152 log.u_bbr.flex3 = bbr->r_ctl.last_in_probertt; 2153 log.u_bbr.flex4 = applied; 2154 log.u_bbr.flex5 = rtt; 2155 log.u_bbr.flex6 = bbr->r_ctl.rc_target_at_state; 2156 log.u_bbr.flex7 = cond; 2157 log.u_bbr.flex8 = reas; 2158 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2159 &bbr->rc_inp->inp_socket->so_rcv, 2160 &bbr->rc_inp->inp_socket->so_snd, 2161 BBR_LOG_RTT_SHRINKS, 0, 2162 0, &log, false, &bbr->rc_tv); 2163 } 2164 } 2165 2166 static void 2167 bbr_log_type_exit_rec(struct tcp_bbr *bbr) 2168 { 2169 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2170 union tcp_log_stackspecific log; 2171 2172 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime); 2173 log.u_bbr.flex1 = bbr->r_ctl.rc_recovery_start; 2174 log.u_bbr.flex2 = bbr->r_ctl.rc_cwnd_on_ent; 2175 log.u_bbr.flex5 = bbr->r_ctl.rc_target_at_state; 2176 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2177 &bbr->rc_inp->inp_socket->so_rcv, 2178 &bbr->rc_inp->inp_socket->so_snd, 2179 BBR_LOG_EXITREC, 0, 2180 0, &log, false, &bbr->rc_tv); 2181 } 2182 } 2183 2184 static void 2185 bbr_log_type_cwndupd(struct tcp_bbr *bbr, uint32_t bytes_this_ack, uint32_t chg, 2186 uint32_t prev_acked, int32_t meth, uint32_t target, uint32_t th_ack, int32_t line) 2187 { 2188 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) { 2189 union tcp_log_stackspecific log; 2190 2191 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime); 2192 log.u_bbr.flex1 = line; 2193 log.u_bbr.flex2 = prev_acked; 2194 log.u_bbr.flex3 = bytes_this_ack; 2195 log.u_bbr.flex4 = chg; 2196 log.u_bbr.flex5 = th_ack; 2197 log.u_bbr.flex6 = target; 2198 log.u_bbr.flex8 = meth; 2199 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2200 &bbr->rc_inp->inp_socket->so_rcv, 2201 &bbr->rc_inp->inp_socket->so_snd, 2202 BBR_LOG_CWND, 0, 2203 0, &log, false, &bbr->rc_tv); 2204 } 2205 } 2206 2207 static void 2208 bbr_log_rtt_sample(struct tcp_bbr *bbr, uint32_t rtt, uint32_t tsin) 2209 { 2210 /* 2211 * Log the rtt sample we are applying to the srtt algorithm in 2212 * useconds. 2213 */ 2214 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2215 union tcp_log_stackspecific log; 2216 2217 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime); 2218 log.u_bbr.flex1 = rtt; 2219 log.u_bbr.flex2 = bbr->r_ctl.rc_bbr_state_time; 2220 log.u_bbr.flex3 = bbr->r_ctl.rc_ack_hdwr_delay; 2221 log.u_bbr.flex4 = bbr->rc_tp->ts_offset; 2222 log.u_bbr.flex5 = bbr->r_ctl.rc_target_at_state; 2223 log.u_bbr.pkts_out = tcp_tv_to_mssectick(&bbr->rc_tv); 2224 log.u_bbr.flex6 = tsin; 2225 log.u_bbr.flex7 = 0; 2226 log.u_bbr.flex8 = bbr->rc_ack_was_delayed; 2227 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2228 &bbr->rc_inp->inp_socket->so_rcv, 2229 &bbr->rc_inp->inp_socket->so_snd, 2230 TCP_LOG_RTT, 0, 2231 0, &log, false, &bbr->rc_tv); 2232 } 2233 } 2234 2235 static void 2236 bbr_log_type_pesist(struct tcp_bbr *bbr, uint32_t cts, uint32_t time_in, int32_t line, uint8_t enter_exit) 2237 { 2238 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) { 2239 union tcp_log_stackspecific log; 2240 2241 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2242 log.u_bbr.flex1 = time_in; 2243 log.u_bbr.flex2 = line; 2244 log.u_bbr.flex8 = enter_exit; 2245 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2246 &bbr->rc_inp->inp_socket->so_rcv, 2247 &bbr->rc_inp->inp_socket->so_snd, 2248 BBR_LOG_PERSIST, 0, 2249 0, &log, false, &bbr->rc_tv); 2250 } 2251 } 2252 static void 2253 bbr_log_ack_clear(struct tcp_bbr *bbr, uint32_t cts) 2254 { 2255 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) { 2256 union tcp_log_stackspecific log; 2257 2258 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2259 log.u_bbr.flex1 = bbr->rc_tp->ts_recent_age; 2260 log.u_bbr.flex2 = bbr->r_ctl.rc_rtt_shrinks; 2261 log.u_bbr.flex3 = bbr->r_ctl.rc_probertt_int; 2262 log.u_bbr.flex4 = bbr->r_ctl.rc_went_idle_time; 2263 log.u_bbr.flex5 = bbr->r_ctl.rc_target_at_state; 2264 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2265 &bbr->rc_inp->inp_socket->so_rcv, 2266 &bbr->rc_inp->inp_socket->so_snd, 2267 BBR_LOG_ACKCLEAR, 0, 2268 0, &log, false, &bbr->rc_tv); 2269 } 2270 } 2271 2272 static void 2273 bbr_log_ack_event(struct tcp_bbr *bbr, struct tcphdr *th, struct tcpopt *to, uint32_t tlen, 2274 uint16_t nsegs, uint32_t cts, int32_t nxt_pkt, struct mbuf *m) 2275 { 2276 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2277 union tcp_log_stackspecific log; 2278 struct timeval tv; 2279 2280 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2281 log.u_bbr.flex1 = nsegs; 2282 log.u_bbr.flex2 = bbr->r_ctl.rc_lost_bytes; 2283 if (m) { 2284 struct timespec ts; 2285 2286 log.u_bbr.flex3 = m->m_flags; 2287 if (m->m_flags & M_TSTMP) { 2288 mbuf_tstmp2timespec(m, &ts); 2289 tv.tv_sec = ts.tv_sec; 2290 tv.tv_usec = ts.tv_nsec / 1000; 2291 log.u_bbr.lt_epoch = tcp_tv_to_usectick(&tv); 2292 } else { 2293 log.u_bbr.lt_epoch = 0; 2294 } 2295 if (m->m_flags & M_TSTMP_LRO) { 2296 tv.tv_sec = m->m_pkthdr.rcv_tstmp / 1000000000; 2297 tv.tv_usec = (m->m_pkthdr.rcv_tstmp % 1000000000) / 1000; 2298 log.u_bbr.flex5 = tcp_tv_to_usectick(&tv); 2299 } else { 2300 /* No arrival timestamp */ 2301 log.u_bbr.flex5 = 0; 2302 } 2303 2304 log.u_bbr.pkts_out = tcp_get_usecs(&tv); 2305 } else { 2306 log.u_bbr.flex3 = 0; 2307 log.u_bbr.flex5 = 0; 2308 log.u_bbr.flex6 = 0; 2309 log.u_bbr.pkts_out = 0; 2310 } 2311 log.u_bbr.flex4 = bbr->r_ctl.rc_target_at_state; 2312 log.u_bbr.flex7 = bbr->r_wanted_output; 2313 log.u_bbr.flex8 = bbr->rc_in_persist; 2314 TCP_LOG_EVENTP(bbr->rc_tp, th, 2315 &bbr->rc_inp->inp_socket->so_rcv, 2316 &bbr->rc_inp->inp_socket->so_snd, 2317 TCP_LOG_IN, 0, 2318 tlen, &log, true, &bbr->rc_tv); 2319 } 2320 } 2321 2322 static void 2323 bbr_log_doseg_done(struct tcp_bbr *bbr, uint32_t cts, int32_t nxt_pkt, int32_t did_out) 2324 { 2325 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2326 union tcp_log_stackspecific log; 2327 2328 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2329 log.u_bbr.flex1 = did_out; 2330 log.u_bbr.flex2 = nxt_pkt; 2331 log.u_bbr.flex3 = bbr->r_ctl.rc_last_delay_val; 2332 log.u_bbr.flex4 = bbr->r_ctl.rc_hpts_flags; 2333 log.u_bbr.flex5 = bbr->r_ctl.rc_timer_exp; 2334 log.u_bbr.flex6 = bbr->r_ctl.rc_lost_bytes; 2335 log.u_bbr.flex7 = bbr->r_wanted_output; 2336 log.u_bbr.flex8 = bbr->rc_in_persist; 2337 log.u_bbr.pkts_out = bbr->r_ctl.highest_hdwr_delay; 2338 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2339 &bbr->rc_inp->inp_socket->so_rcv, 2340 &bbr->rc_inp->inp_socket->so_snd, 2341 BBR_LOG_DOSEG_DONE, 0, 2342 0, &log, true, &bbr->rc_tv); 2343 } 2344 } 2345 2346 static void 2347 bbr_log_enobuf_jmp(struct tcp_bbr *bbr, uint32_t len, uint32_t cts, 2348 int32_t line, uint32_t o_len, uint32_t segcnt, uint32_t segsiz) 2349 { 2350 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2351 union tcp_log_stackspecific log; 2352 2353 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2354 log.u_bbr.flex1 = line; 2355 log.u_bbr.flex2 = o_len; 2356 log.u_bbr.flex3 = segcnt; 2357 log.u_bbr.flex4 = segsiz; 2358 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2359 &bbr->rc_inp->inp_socket->so_rcv, 2360 &bbr->rc_inp->inp_socket->so_snd, 2361 BBR_LOG_ENOBUF_JMP, ENOBUFS, 2362 len, &log, true, &bbr->rc_tv); 2363 } 2364 } 2365 2366 static void 2367 bbr_log_to_processing(struct tcp_bbr *bbr, uint32_t cts, int32_t ret, int32_t timers, uint8_t hpts_calling) 2368 { 2369 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2370 union tcp_log_stackspecific log; 2371 2372 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2373 log.u_bbr.flex1 = timers; 2374 log.u_bbr.flex2 = ret; 2375 log.u_bbr.flex3 = bbr->r_ctl.rc_timer_exp; 2376 log.u_bbr.flex4 = bbr->r_ctl.rc_hpts_flags; 2377 log.u_bbr.flex5 = cts; 2378 log.u_bbr.flex6 = bbr->r_ctl.rc_target_at_state; 2379 log.u_bbr.flex8 = hpts_calling; 2380 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2381 &bbr->rc_inp->inp_socket->so_rcv, 2382 &bbr->rc_inp->inp_socket->so_snd, 2383 BBR_LOG_TO_PROCESS, 0, 2384 0, &log, false, &bbr->rc_tv); 2385 } 2386 } 2387 2388 static void 2389 bbr_log_to_event(struct tcp_bbr *bbr, uint32_t cts, int32_t to_num) 2390 { 2391 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2392 union tcp_log_stackspecific log; 2393 uint64_t ar; 2394 2395 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2396 log.u_bbr.flex1 = bbr->bbr_timer_src; 2397 log.u_bbr.flex2 = 0; 2398 log.u_bbr.flex3 = bbr->r_ctl.rc_hpts_flags; 2399 ar = (uint64_t)(bbr->r_ctl.rc_resend); 2400 ar >>= 32; 2401 ar &= 0x00000000ffffffff; 2402 log.u_bbr.flex4 = (uint32_t)ar; 2403 ar = (uint64_t)bbr->r_ctl.rc_resend; 2404 ar &= 0x00000000ffffffff; 2405 log.u_bbr.flex5 = (uint32_t)ar; 2406 log.u_bbr.flex6 = TICKS_2_USEC(bbr->rc_tp->t_rxtcur); 2407 log.u_bbr.flex8 = to_num; 2408 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2409 &bbr->rc_inp->inp_socket->so_rcv, 2410 &bbr->rc_inp->inp_socket->so_snd, 2411 BBR_LOG_RTO, 0, 2412 0, &log, false, &bbr->rc_tv); 2413 } 2414 } 2415 2416 static void 2417 bbr_log_startup_event(struct tcp_bbr *bbr, uint32_t cts, uint32_t flex1, uint32_t flex2, uint32_t flex3, uint8_t reason) 2418 { 2419 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2420 union tcp_log_stackspecific log; 2421 2422 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2423 log.u_bbr.flex1 = flex1; 2424 log.u_bbr.flex2 = flex2; 2425 log.u_bbr.flex3 = flex3; 2426 log.u_bbr.flex4 = 0; 2427 log.u_bbr.flex5 = bbr->r_ctl.rc_target_at_state; 2428 log.u_bbr.flex6 = bbr->r_ctl.rc_lost_at_startup; 2429 log.u_bbr.flex8 = reason; 2430 log.u_bbr.cur_del_rate = bbr->r_ctl.rc_bbr_lastbtlbw; 2431 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2432 &bbr->rc_inp->inp_socket->so_rcv, 2433 &bbr->rc_inp->inp_socket->so_snd, 2434 BBR_LOG_REDUCE, 0, 2435 0, &log, false, &bbr->rc_tv); 2436 } 2437 } 2438 2439 static void 2440 bbr_log_hpts_diag(struct tcp_bbr *bbr, uint32_t cts, struct hpts_diag *diag) 2441 { 2442 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) { 2443 union tcp_log_stackspecific log; 2444 2445 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2446 log.u_bbr.flex1 = diag->p_nxt_slot; 2447 log.u_bbr.flex2 = diag->p_cur_slot; 2448 log.u_bbr.flex3 = diag->slot_req; 2449 log.u_bbr.flex4 = diag->inp_hptsslot; 2450 log.u_bbr.flex5 = diag->slot_remaining; 2451 log.u_bbr.flex6 = diag->need_new_to; 2452 log.u_bbr.flex7 = diag->p_hpts_active; 2453 log.u_bbr.flex8 = diag->p_on_min_sleep; 2454 /* Hijack other fields as needed */ 2455 log.u_bbr.epoch = diag->have_slept; 2456 log.u_bbr.lt_epoch = diag->yet_to_sleep; 2457 log.u_bbr.pkts_out = diag->co_ret; 2458 log.u_bbr.applimited = diag->hpts_sleep_time; 2459 log.u_bbr.delivered = diag->p_prev_slot; 2460 log.u_bbr.inflight = diag->p_runningtick; 2461 log.u_bbr.bw_inuse = diag->wheel_tick; 2462 log.u_bbr.rttProp = diag->wheel_cts; 2463 log.u_bbr.delRate = diag->maxticks; 2464 log.u_bbr.cur_del_rate = diag->p_curtick; 2465 log.u_bbr.cur_del_rate <<= 32; 2466 log.u_bbr.cur_del_rate |= diag->p_lasttick; 2467 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2468 &bbr->rc_inp->inp_socket->so_rcv, 2469 &bbr->rc_inp->inp_socket->so_snd, 2470 BBR_LOG_HPTSDIAG, 0, 2471 0, &log, false, &bbr->rc_tv); 2472 } 2473 } 2474 2475 static void 2476 bbr_log_timer_var(struct tcp_bbr *bbr, int mode, uint32_t cts, uint32_t time_since_sent, uint32_t srtt, 2477 uint32_t thresh, uint32_t to) 2478 { 2479 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) { 2480 union tcp_log_stackspecific log; 2481 2482 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2483 log.u_bbr.flex1 = bbr->rc_tp->t_rttvar; 2484 log.u_bbr.flex2 = time_since_sent; 2485 log.u_bbr.flex3 = srtt; 2486 log.u_bbr.flex4 = thresh; 2487 log.u_bbr.flex5 = to; 2488 log.u_bbr.flex6 = bbr->rc_tp->t_srtt; 2489 log.u_bbr.flex8 = mode; 2490 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2491 &bbr->rc_inp->inp_socket->so_rcv, 2492 &bbr->rc_inp->inp_socket->so_snd, 2493 BBR_LOG_TIMERPREP, 0, 2494 0, &log, false, &bbr->rc_tv); 2495 } 2496 } 2497 2498 static void 2499 bbr_log_pacing_delay_calc(struct tcp_bbr *bbr, uint16_t gain, uint32_t len, 2500 uint32_t cts, uint32_t usecs, uint64_t bw, uint32_t override, int mod) 2501 { 2502 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2503 union tcp_log_stackspecific log; 2504 2505 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2506 log.u_bbr.flex1 = usecs; 2507 log.u_bbr.flex2 = len; 2508 log.u_bbr.flex3 = (uint32_t)((bw >> 32) & 0x00000000ffffffff); 2509 log.u_bbr.flex4 = (uint32_t)(bw & 0x00000000ffffffff); 2510 if (override) 2511 log.u_bbr.flex5 = (1 << 2); 2512 else 2513 log.u_bbr.flex5 = 0; 2514 log.u_bbr.flex6 = override; 2515 log.u_bbr.flex7 = gain; 2516 log.u_bbr.flex8 = mod; 2517 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2518 &bbr->rc_inp->inp_socket->so_rcv, 2519 &bbr->rc_inp->inp_socket->so_snd, 2520 BBR_LOG_HPTSI_CALC, 0, 2521 len, &log, false, &bbr->rc_tv); 2522 } 2523 } 2524 2525 static void 2526 bbr_log_to_start(struct tcp_bbr *bbr, uint32_t cts, uint32_t to, int32_t slot, uint8_t which) 2527 { 2528 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2529 union tcp_log_stackspecific log; 2530 2531 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2532 2533 log.u_bbr.flex1 = bbr->bbr_timer_src; 2534 log.u_bbr.flex2 = to; 2535 log.u_bbr.flex3 = bbr->r_ctl.rc_hpts_flags; 2536 log.u_bbr.flex4 = slot; 2537 log.u_bbr.flex5 = bbr->rc_inp->inp_hptsslot; 2538 log.u_bbr.flex6 = TICKS_2_USEC(bbr->rc_tp->t_rxtcur); 2539 log.u_bbr.pkts_out = bbr->rc_inp->inp_flags2; 2540 log.u_bbr.flex8 = which; 2541 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2542 &bbr->rc_inp->inp_socket->so_rcv, 2543 &bbr->rc_inp->inp_socket->so_snd, 2544 BBR_LOG_TIMERSTAR, 0, 2545 0, &log, false, &bbr->rc_tv); 2546 } 2547 } 2548 2549 static void 2550 bbr_log_thresh_choice(struct tcp_bbr *bbr, uint32_t cts, uint32_t thresh, uint32_t lro, uint32_t srtt, struct bbr_sendmap *rsm, uint8_t frm) 2551 { 2552 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) { 2553 union tcp_log_stackspecific log; 2554 2555 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2556 log.u_bbr.flex1 = thresh; 2557 log.u_bbr.flex2 = lro; 2558 log.u_bbr.flex3 = bbr->r_ctl.rc_reorder_ts; 2559 log.u_bbr.flex4 = rsm->r_tim_lastsent[(rsm->r_rtr_cnt - 1)]; 2560 log.u_bbr.flex5 = TICKS_2_USEC(bbr->rc_tp->t_rxtcur); 2561 log.u_bbr.flex6 = srtt; 2562 log.u_bbr.flex7 = bbr->r_ctl.rc_reorder_shift; 2563 log.u_bbr.flex8 = frm; 2564 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2565 &bbr->rc_inp->inp_socket->so_rcv, 2566 &bbr->rc_inp->inp_socket->so_snd, 2567 BBR_LOG_THRESH_CALC, 0, 2568 0, &log, false, &bbr->rc_tv); 2569 } 2570 } 2571 2572 static void 2573 bbr_log_to_cancel(struct tcp_bbr *bbr, int32_t line, uint32_t cts, uint8_t hpts_removed) 2574 { 2575 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2576 union tcp_log_stackspecific log; 2577 2578 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2579 log.u_bbr.flex1 = line; 2580 log.u_bbr.flex2 = bbr->bbr_timer_src; 2581 log.u_bbr.flex3 = bbr->r_ctl.rc_hpts_flags; 2582 log.u_bbr.flex4 = bbr->rc_in_persist; 2583 log.u_bbr.flex5 = bbr->r_ctl.rc_target_at_state; 2584 log.u_bbr.flex6 = TICKS_2_USEC(bbr->rc_tp->t_rxtcur); 2585 log.u_bbr.flex8 = hpts_removed; 2586 log.u_bbr.pkts_out = bbr->rc_pacer_started; 2587 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2588 &bbr->rc_inp->inp_socket->so_rcv, 2589 &bbr->rc_inp->inp_socket->so_snd, 2590 BBR_LOG_TIMERCANC, 0, 2591 0, &log, false, &bbr->rc_tv); 2592 } 2593 } 2594 2595 2596 static void 2597 bbr_log_tstmp_validation(struct tcp_bbr *bbr, uint64_t peer_delta, uint64_t delta) 2598 { 2599 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2600 union tcp_log_stackspecific log; 2601 2602 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime); 2603 log.u_bbr.flex1 = bbr->r_ctl.bbr_peer_tsratio; 2604 log.u_bbr.flex2 = (peer_delta >> 32); 2605 log.u_bbr.flex3 = (peer_delta & 0x00000000ffffffff); 2606 log.u_bbr.flex4 = (delta >> 32); 2607 log.u_bbr.flex5 = (delta & 0x00000000ffffffff); 2608 log.u_bbr.flex7 = bbr->rc_ts_clock_set; 2609 log.u_bbr.flex8 = bbr->rc_ts_cant_be_used; 2610 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2611 &bbr->rc_inp->inp_socket->so_rcv, 2612 &bbr->rc_inp->inp_socket->so_snd, 2613 BBR_LOG_TSTMP_VAL, 0, 2614 0, &log, false, &bbr->rc_tv); 2615 2616 } 2617 } 2618 2619 static void 2620 bbr_log_type_tsosize(struct tcp_bbr *bbr, uint32_t cts, uint32_t tsosz, uint32_t tls, uint32_t old_val, uint32_t maxseg, int hdwr) 2621 { 2622 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2623 union tcp_log_stackspecific log; 2624 2625 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2626 log.u_bbr.flex1 = tsosz; 2627 log.u_bbr.flex2 = tls; 2628 log.u_bbr.flex3 = tcp_min_hptsi_time; 2629 log.u_bbr.flex4 = bbr->r_ctl.bbr_hptsi_bytes_min; 2630 log.u_bbr.flex5 = old_val; 2631 log.u_bbr.flex6 = maxseg; 2632 log.u_bbr.flex7 = bbr->rc_no_pacing; 2633 log.u_bbr.flex7 <<= 1; 2634 log.u_bbr.flex7 |= bbr->rc_past_init_win; 2635 if (hdwr) 2636 log.u_bbr.flex8 = 0x80 | bbr->rc_use_google; 2637 else 2638 log.u_bbr.flex8 = bbr->rc_use_google; 2639 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2640 &bbr->rc_inp->inp_socket->so_rcv, 2641 &bbr->rc_inp->inp_socket->so_snd, 2642 BBR_LOG_BBRTSO, 0, 2643 0, &log, false, &bbr->rc_tv); 2644 } 2645 } 2646 2647 static void 2648 bbr_log_type_rsmclear(struct tcp_bbr *bbr, uint32_t cts, struct bbr_sendmap *rsm, 2649 uint32_t flags, uint32_t line) 2650 { 2651 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2652 union tcp_log_stackspecific log; 2653 2654 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2655 log.u_bbr.flex1 = line; 2656 log.u_bbr.flex2 = rsm->r_start; 2657 log.u_bbr.flex3 = rsm->r_end; 2658 log.u_bbr.flex4 = rsm->r_delivered; 2659 log.u_bbr.flex5 = rsm->r_rtr_cnt; 2660 log.u_bbr.flex6 = rsm->r_dupack; 2661 log.u_bbr.flex7 = rsm->r_tim_lastsent[0]; 2662 log.u_bbr.flex8 = rsm->r_flags; 2663 /* Hijack the pkts_out fids */ 2664 log.u_bbr.applimited = flags; 2665 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2666 &bbr->rc_inp->inp_socket->so_rcv, 2667 &bbr->rc_inp->inp_socket->so_snd, 2668 BBR_RSM_CLEARED, 0, 2669 0, &log, false, &bbr->rc_tv); 2670 } 2671 } 2672 2673 static void 2674 bbr_log_type_bbrupd(struct tcp_bbr *bbr, uint8_t flex8, uint32_t cts, 2675 uint32_t flex3, uint32_t flex2, uint32_t flex5, 2676 uint32_t flex6, uint32_t pkts_out, int flex7, 2677 uint32_t flex4, uint32_t flex1) 2678 { 2679 2680 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2681 union tcp_log_stackspecific log; 2682 2683 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2684 log.u_bbr.flex1 = flex1; 2685 log.u_bbr.flex2 = flex2; 2686 log.u_bbr.flex3 = flex3; 2687 log.u_bbr.flex4 = flex4; 2688 log.u_bbr.flex5 = flex5; 2689 log.u_bbr.flex6 = flex6; 2690 log.u_bbr.flex7 = flex7; 2691 /* Hijack the pkts_out fids */ 2692 log.u_bbr.pkts_out = pkts_out; 2693 log.u_bbr.flex8 = flex8; 2694 if (bbr->rc_ack_was_delayed) 2695 log.u_bbr.epoch = bbr->r_ctl.rc_ack_hdwr_delay; 2696 else 2697 log.u_bbr.epoch = 0; 2698 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2699 &bbr->rc_inp->inp_socket->so_rcv, 2700 &bbr->rc_inp->inp_socket->so_snd, 2701 BBR_LOG_BBRUPD, 0, 2702 flex2, &log, false, &bbr->rc_tv); 2703 } 2704 } 2705 2706 2707 static void 2708 bbr_log_type_ltbw(struct tcp_bbr *bbr, uint32_t cts, int32_t reason, 2709 uint32_t newbw, uint32_t obw, uint32_t diff, 2710 uint32_t tim) 2711 { 2712 if (/*bbr_verbose_logging && */(bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) { 2713 union tcp_log_stackspecific log; 2714 2715 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2716 log.u_bbr.flex1 = reason; 2717 log.u_bbr.flex2 = newbw; 2718 log.u_bbr.flex3 = obw; 2719 log.u_bbr.flex4 = diff; 2720 log.u_bbr.flex5 = bbr->r_ctl.rc_lt_lost; 2721 log.u_bbr.flex6 = bbr->r_ctl.rc_lt_del; 2722 log.u_bbr.flex7 = bbr->rc_lt_is_sampling; 2723 log.u_bbr.pkts_out = tim; 2724 log.u_bbr.bw_inuse = bbr->r_ctl.rc_lt_bw; 2725 if (bbr->rc_lt_use_bw == 0) 2726 log.u_bbr.epoch = bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_lt_epoch; 2727 else 2728 log.u_bbr.epoch = bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_lt_epoch_use; 2729 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2730 &bbr->rc_inp->inp_socket->so_rcv, 2731 &bbr->rc_inp->inp_socket->so_snd, 2732 BBR_LOG_BWSAMP, 0, 2733 0, &log, false, &bbr->rc_tv); 2734 } 2735 } 2736 2737 static inline void 2738 bbr_log_progress_event(struct tcp_bbr *bbr, struct tcpcb *tp, uint32_t tick, int event, int line) 2739 { 2740 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) { 2741 union tcp_log_stackspecific log; 2742 2743 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime); 2744 log.u_bbr.flex1 = line; 2745 log.u_bbr.flex2 = tick; 2746 log.u_bbr.flex3 = tp->t_maxunacktime; 2747 log.u_bbr.flex4 = tp->t_acktime; 2748 log.u_bbr.flex8 = event; 2749 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2750 &bbr->rc_inp->inp_socket->so_rcv, 2751 &bbr->rc_inp->inp_socket->so_snd, 2752 BBR_LOG_PROGRESS, 0, 2753 0, &log, false, &bbr->rc_tv); 2754 } 2755 } 2756 2757 static void 2758 bbr_type_log_hdwr_pacing(struct tcp_bbr *bbr, const struct ifnet *ifp, 2759 uint64_t rate, uint64_t hw_rate, int line, uint32_t cts, 2760 int error) 2761 { 2762 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2763 union tcp_log_stackspecific log; 2764 2765 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2766 log.u_bbr.flex1 = ((hw_rate >> 32) & 0x00000000ffffffff); 2767 log.u_bbr.flex2 = (hw_rate & 0x00000000ffffffff); 2768 log.u_bbr.flex3 = (((uint64_t)ifp >> 32) & 0x00000000ffffffff); 2769 log.u_bbr.flex4 = ((uint64_t)ifp & 0x00000000ffffffff); 2770 log.u_bbr.bw_inuse = rate; 2771 log.u_bbr.flex5 = line; 2772 log.u_bbr.flex6 = error; 2773 log.u_bbr.flex8 = bbr->skip_gain; 2774 log.u_bbr.flex8 <<= 1; 2775 log.u_bbr.flex8 |= bbr->gain_is_limited; 2776 log.u_bbr.flex8 <<= 1; 2777 log.u_bbr.flex8 |= bbr->bbr_hdrw_pacing; 2778 log.u_bbr.pkts_out = bbr->rc_tp->t_maxseg; 2779 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2780 &bbr->rc_inp->inp_socket->so_rcv, 2781 &bbr->rc_inp->inp_socket->so_snd, 2782 BBR_LOG_HDWR_PACE, 0, 2783 0, &log, false, &bbr->rc_tv); 2784 } 2785 } 2786 2787 static void 2788 bbr_log_type_bbrsnd(struct tcp_bbr *bbr, uint32_t len, uint32_t slot, uint32_t del_by, uint32_t cts, uint32_t line, uint32_t prev_delay) 2789 { 2790 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2791 union tcp_log_stackspecific log; 2792 2793 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2794 log.u_bbr.flex1 = slot; 2795 log.u_bbr.flex2 = del_by; 2796 log.u_bbr.flex3 = prev_delay; 2797 log.u_bbr.flex4 = line; 2798 log.u_bbr.flex5 = bbr->r_ctl.rc_last_delay_val; 2799 log.u_bbr.flex6 = bbr->r_ctl.rc_hptsi_agg_delay; 2800 log.u_bbr.flex7 = (0x0000ffff & bbr->r_ctl.rc_hpts_flags); 2801 log.u_bbr.flex8 = bbr->rc_in_persist; 2802 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2803 &bbr->rc_inp->inp_socket->so_rcv, 2804 &bbr->rc_inp->inp_socket->so_snd, 2805 BBR_LOG_BBRSND, 0, 2806 len, &log, false, &bbr->rc_tv); 2807 } 2808 } 2809 2810 static void 2811 bbr_log_type_bbrrttprop(struct tcp_bbr *bbr, uint32_t t, uint32_t end, uint32_t tsconv, uint32_t cts, int32_t match, uint32_t seq, uint8_t flags) 2812 { 2813 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2814 union tcp_log_stackspecific log; 2815 2816 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2817 log.u_bbr.flex1 = bbr->r_ctl.rc_delivered; 2818 log.u_bbr.flex2 = 0; 2819 log.u_bbr.flex3 = bbr->r_ctl.rc_lowest_rtt; 2820 log.u_bbr.flex4 = end; 2821 log.u_bbr.flex5 = seq; 2822 log.u_bbr.flex6 = t; 2823 log.u_bbr.flex7 = match; 2824 log.u_bbr.flex8 = flags; 2825 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2826 &bbr->rc_inp->inp_socket->so_rcv, 2827 &bbr->rc_inp->inp_socket->so_snd, 2828 BBR_LOG_BBRRTT, 0, 2829 0, &log, false, &bbr->rc_tv); 2830 } 2831 } 2832 2833 static void 2834 bbr_log_exit_gain(struct tcp_bbr *bbr, uint32_t cts, int32_t entry_method) 2835 { 2836 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2837 union tcp_log_stackspecific log; 2838 2839 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2840 log.u_bbr.flex1 = bbr->r_ctl.rc_target_at_state; 2841 log.u_bbr.flex2 = (bbr->rc_tp->t_maxseg - bbr->rc_last_options); 2842 log.u_bbr.flex3 = bbr->r_ctl.gain_epoch; 2843 log.u_bbr.flex4 = bbr->r_ctl.rc_pace_max_segs; 2844 log.u_bbr.flex5 = bbr->r_ctl.rc_pace_min_segs; 2845 log.u_bbr.flex6 = bbr->r_ctl.rc_bbr_state_atflight; 2846 log.u_bbr.flex7 = 0; 2847 log.u_bbr.flex8 = entry_method; 2848 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2849 &bbr->rc_inp->inp_socket->so_rcv, 2850 &bbr->rc_inp->inp_socket->so_snd, 2851 BBR_LOG_EXIT_GAIN, 0, 2852 0, &log, false, &bbr->rc_tv); 2853 } 2854 } 2855 2856 static void 2857 bbr_log_settings_change(struct tcp_bbr *bbr, int settings_desired) 2858 { 2859 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) { 2860 union tcp_log_stackspecific log; 2861 2862 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime); 2863 /* R-HU */ 2864 log.u_bbr.flex1 = 0; 2865 log.u_bbr.flex2 = 0; 2866 log.u_bbr.flex3 = 0; 2867 log.u_bbr.flex4 = 0; 2868 log.u_bbr.flex7 = 0; 2869 log.u_bbr.flex8 = settings_desired; 2870 2871 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2872 &bbr->rc_inp->inp_socket->so_rcv, 2873 &bbr->rc_inp->inp_socket->so_snd, 2874 BBR_LOG_SETTINGS_CHG, 0, 2875 0, &log, false, &bbr->rc_tv); 2876 } 2877 } 2878 2879 /* 2880 * Returns the bw from the our filter. 2881 */ 2882 static inline uint64_t 2883 bbr_get_full_bw(struct tcp_bbr *bbr) 2884 { 2885 uint64_t bw; 2886 2887 bw = get_filter_value(&bbr->r_ctl.rc_delrate); 2888 2889 return (bw); 2890 } 2891 2892 static inline void 2893 bbr_set_pktepoch(struct tcp_bbr *bbr, uint32_t cts, int32_t line) 2894 { 2895 uint64_t calclr; 2896 uint32_t lost, del; 2897 2898 if (bbr->r_ctl.rc_lost > bbr->r_ctl.rc_lost_at_pktepoch) 2899 lost = bbr->r_ctl.rc_lost - bbr->r_ctl.rc_lost_at_pktepoch; 2900 else 2901 lost = 0; 2902 del = bbr->r_ctl.rc_delivered - bbr->r_ctl.rc_pkt_epoch_del; 2903 if (lost == 0) { 2904 calclr = 0; 2905 } else if (del) { 2906 calclr = lost; 2907 calclr *= (uint64_t)1000; 2908 calclr /= (uint64_t)del; 2909 } else { 2910 /* Nothing delivered? 100.0% loss */ 2911 calclr = 1000; 2912 } 2913 bbr->r_ctl.rc_pkt_epoch_loss_rate = (uint32_t)calclr; 2914 if (IN_RECOVERY(bbr->rc_tp->t_flags)) 2915 bbr->r_ctl.recovery_lr += (uint32_t)calclr; 2916 bbr->r_ctl.rc_pkt_epoch++; 2917 if (bbr->rc_no_pacing && 2918 (bbr->r_ctl.rc_pkt_epoch >= bbr->no_pacing_until)) { 2919 bbr->rc_no_pacing = 0; 2920 tcp_bbr_tso_size_check(bbr, cts); 2921 } 2922 bbr->r_ctl.rc_pkt_epoch_rtt = bbr_calc_time(cts, bbr->r_ctl.rc_pkt_epoch_time); 2923 bbr->r_ctl.rc_pkt_epoch_time = cts; 2924 /* What was our loss rate */ 2925 bbr_log_pkt_epoch(bbr, cts, line, lost, del); 2926 bbr->r_ctl.rc_pkt_epoch_del = bbr->r_ctl.rc_delivered; 2927 bbr->r_ctl.rc_lost_at_pktepoch = bbr->r_ctl.rc_lost; 2928 } 2929 2930 static inline void 2931 bbr_set_epoch(struct tcp_bbr *bbr, uint32_t cts, int32_t line) 2932 { 2933 uint32_t epoch_time; 2934 2935 /* Tick the RTT clock */ 2936 bbr->r_ctl.rc_rtt_epoch++; 2937 epoch_time = cts - bbr->r_ctl.rc_rcv_epoch_start; 2938 bbr_log_time_epoch(bbr, cts, line, epoch_time); 2939 bbr->r_ctl.rc_rcv_epoch_start = cts; 2940 } 2941 2942 2943 static inline void 2944 bbr_isit_a_pkt_epoch(struct tcp_bbr *bbr, uint32_t cts, struct bbr_sendmap *rsm, int32_t line, int32_t cum_acked) 2945 { 2946 if (SEQ_GEQ(rsm->r_delivered, bbr->r_ctl.rc_pkt_epoch_del)) { 2947 bbr->rc_is_pkt_epoch_now = 1; 2948 } 2949 } 2950 2951 /* 2952 * Returns the bw from either the b/w filter 2953 * or from the lt_bw (if the connection is being 2954 * policed). 2955 */ 2956 static inline uint64_t 2957 __bbr_get_bw(struct tcp_bbr *bbr) 2958 { 2959 uint64_t bw, min_bw; 2960 uint64_t rtt; 2961 int gm_measure_cnt = 1; 2962 2963 /* 2964 * For startup we make, like google, a 2965 * minimum b/w. This is generated from the 2966 * IW and the rttProp. We do fall back to srtt 2967 * if for some reason (initial handshake) we don't 2968 * have a rttProp. We, in the worst case, fall back 2969 * to the configured min_bw (rc_initial_hptsi_bw). 2970 */ 2971 if (bbr->rc_bbr_state == BBR_STATE_STARTUP) { 2972 /* Attempt first to use rttProp */ 2973 rtt = (uint64_t)get_filter_value_small(&bbr->r_ctl.rc_rttprop); 2974 if (rtt && (rtt < 0xffffffff)) { 2975 measure: 2976 min_bw = (uint64_t)(bbr_initial_cwnd(bbr, bbr->rc_tp)) * 2977 ((uint64_t)1000000); 2978 min_bw /= rtt; 2979 if (min_bw < bbr->r_ctl.rc_initial_hptsi_bw) { 2980 min_bw = bbr->r_ctl.rc_initial_hptsi_bw; 2981 } 2982 2983 } else if (bbr->rc_tp->t_srtt != 0) { 2984 /* No rttProp, use srtt? */ 2985 rtt = bbr_get_rtt(bbr, BBR_SRTT); 2986 goto measure; 2987 } else { 2988 min_bw = bbr->r_ctl.rc_initial_hptsi_bw; 2989 } 2990 } else 2991 min_bw = 0; 2992 2993 if ((bbr->rc_past_init_win == 0) && 2994 (bbr->r_ctl.rc_delivered > bbr_initial_cwnd(bbr, bbr->rc_tp))) 2995 bbr->rc_past_init_win = 1; 2996 if ((bbr->rc_use_google) && (bbr->r_ctl.r_measurement_count >= 1)) 2997 gm_measure_cnt = 0; 2998 if (gm_measure_cnt && 2999 ((bbr->r_ctl.r_measurement_count < bbr_min_measurements_req) || 3000 (bbr->rc_past_init_win == 0))) { 3001 /* For google we use our guess rate until we get 1 measurement */ 3002 3003 use_initial_window: 3004 rtt = (uint64_t)get_filter_value_small(&bbr->r_ctl.rc_rttprop); 3005 if (rtt && (rtt < 0xffffffff)) { 3006 /* 3007 * We have an RTT measurment. Use that in 3008 * combination with our initial window to calculate 3009 * a b/w. 3010 */ 3011 bw = (uint64_t)(bbr_initial_cwnd(bbr, bbr->rc_tp)) * 3012 ((uint64_t)1000000); 3013 bw /= rtt; 3014 if (bw < bbr->r_ctl.rc_initial_hptsi_bw) { 3015 bw = bbr->r_ctl.rc_initial_hptsi_bw; 3016 } 3017 } else { 3018 /* Drop back to the 40 and punt to a default */ 3019 bw = bbr->r_ctl.rc_initial_hptsi_bw; 3020 } 3021 if (bw < 1) 3022 /* Probably should panic */ 3023 bw = 1; 3024 if (bw > min_bw) 3025 return (bw); 3026 else 3027 return (min_bw); 3028 } 3029 if (bbr->rc_lt_use_bw) 3030 bw = bbr->r_ctl.rc_lt_bw; 3031 else if (bbr->r_recovery_bw && (bbr->rc_use_google == 0)) 3032 bw = bbr->r_ctl.red_bw; 3033 else 3034 bw = get_filter_value(&bbr->r_ctl.rc_delrate); 3035 if (bbr->rc_tp->t_peakrate_thr && (bbr->rc_use_google == 0)) { 3036 /* 3037 * Enforce user set rate limit, keep in mind that 3038 * t_peakrate_thr is in B/s already 3039 */ 3040 bw = uqmin((uint64_t)bbr->rc_tp->t_peakrate_thr, bw); 3041 } 3042 if (bw == 0) { 3043 /* We should not be at 0, go to the initial window then */ 3044 goto use_initial_window; 3045 } 3046 if (bw < 1) 3047 /* Probably should panic */ 3048 bw = 1; 3049 if (bw < min_bw) 3050 bw = min_bw; 3051 return (bw); 3052 } 3053 3054 static inline uint64_t 3055 bbr_get_bw(struct tcp_bbr *bbr) 3056 { 3057 uint64_t bw; 3058 3059 bw = __bbr_get_bw(bbr); 3060 return (bw); 3061 } 3062 3063 static inline void 3064 bbr_reset_lt_bw_interval(struct tcp_bbr *bbr, uint32_t cts) 3065 { 3066 bbr->r_ctl.rc_lt_epoch = bbr->r_ctl.rc_pkt_epoch; 3067 bbr->r_ctl.rc_lt_time = bbr->r_ctl.rc_del_time; 3068 bbr->r_ctl.rc_lt_del = bbr->r_ctl.rc_delivered; 3069 bbr->r_ctl.rc_lt_lost = bbr->r_ctl.rc_lost; 3070 } 3071 3072 static inline void 3073 bbr_reset_lt_bw_sampling(struct tcp_bbr *bbr, uint32_t cts) 3074 { 3075 bbr->rc_lt_is_sampling = 0; 3076 bbr->rc_lt_use_bw = 0; 3077 bbr->r_ctl.rc_lt_bw = 0; 3078 bbr_reset_lt_bw_interval(bbr, cts); 3079 } 3080 3081 static inline void 3082 bbr_lt_bw_samp_done(struct tcp_bbr *bbr, uint64_t bw, uint32_t cts, uint32_t timin) 3083 { 3084 uint64_t diff; 3085 3086 /* Do we have a previous sample? */ 3087 if (bbr->r_ctl.rc_lt_bw) { 3088 /* Get the diff in bytes per second */ 3089 if (bbr->r_ctl.rc_lt_bw > bw) 3090 diff = bbr->r_ctl.rc_lt_bw - bw; 3091 else 3092 diff = bw - bbr->r_ctl.rc_lt_bw; 3093 if ((diff <= bbr_lt_bw_diff) || 3094 (diff <= (bbr->r_ctl.rc_lt_bw / bbr_lt_bw_ratio))) { 3095 /* Consider us policed */ 3096 uint32_t saved_bw; 3097 3098 saved_bw = (uint32_t)bbr->r_ctl.rc_lt_bw; 3099 bbr->r_ctl.rc_lt_bw = (bw + bbr->r_ctl.rc_lt_bw) / 2; /* average of two */ 3100 bbr->rc_lt_use_bw = 1; 3101 bbr->r_ctl.rc_bbr_hptsi_gain = BBR_UNIT; 3102 /* 3103 * Use pkt based epoch for measuring length of 3104 * policer up 3105 */ 3106 bbr->r_ctl.rc_lt_epoch_use = bbr->r_ctl.rc_pkt_epoch; 3107 /* 3108 * reason 4 is we need to start consider being 3109 * policed 3110 */ 3111 bbr_log_type_ltbw(bbr, cts, 4, (uint32_t)bw, saved_bw, (uint32_t)diff, timin); 3112 return; 3113 } 3114 } 3115 bbr->r_ctl.rc_lt_bw = bw; 3116 bbr_reset_lt_bw_interval(bbr, cts); 3117 bbr_log_type_ltbw(bbr, cts, 5, 0, (uint32_t)bw, 0, timin); 3118 } 3119 3120 /* 3121 * RRS: Copied from user space! 3122 * Calculate a uniformly distributed random number less than upper_bound 3123 * avoiding "modulo bias". 3124 * 3125 * Uniformity is achieved by generating new random numbers until the one 3126 * returned is outside the range [0, 2**32 % upper_bound). This 3127 * guarantees the selected random number will be inside 3128 * [2**32 % upper_bound, 2**32) which maps back to [0, upper_bound) 3129 * after reduction modulo upper_bound. 3130 */ 3131 static uint32_t 3132 arc4random_uniform(uint32_t upper_bound) 3133 { 3134 uint32_t r, min; 3135 3136 if (upper_bound < 2) 3137 return 0; 3138 3139 /* 2**32 % x == (2**32 - x) % x */ 3140 min = -upper_bound % upper_bound; 3141 3142 /* 3143 * This could theoretically loop forever but each retry has 3144 * p > 0.5 (worst case, usually far better) of selecting a 3145 * number inside the range we need, so it should rarely need 3146 * to re-roll. 3147 */ 3148 for (;;) { 3149 r = arc4random(); 3150 if (r >= min) 3151 break; 3152 } 3153 3154 return r % upper_bound; 3155 } 3156 3157 static void 3158 bbr_randomize_extra_state_time(struct tcp_bbr *bbr) 3159 { 3160 uint32_t ran, deduct; 3161 3162 ran = arc4random_uniform(bbr_rand_ot); 3163 if (ran) { 3164 deduct = bbr->r_ctl.rc_level_state_extra / ran; 3165 bbr->r_ctl.rc_level_state_extra -= deduct; 3166 } 3167 } 3168 /* 3169 * Return randomly the starting state 3170 * to use in probebw. 3171 */ 3172 static uint8_t 3173 bbr_pick_probebw_substate(struct tcp_bbr *bbr, uint32_t cts) 3174 { 3175 uint32_t ran; 3176 uint8_t ret_val; 3177 3178 /* Initialize the offset to 0 */ 3179 bbr->r_ctl.rc_exta_time_gd = 0; 3180 bbr->rc_hit_state_1 = 0; 3181 bbr->r_ctl.rc_level_state_extra = 0; 3182 ran = arc4random_uniform((BBR_SUBSTATE_COUNT-1)); 3183 /* 3184 * The math works funny here :) the return value is used to set the 3185 * substate and then the state change is called which increments by 3186 * one. So if we return 1 (DRAIN) we will increment to 2 (LEVEL1) when 3187 * we fully enter the state. Note that the (8 - 1 - ran) assures that 3188 * we return 1 - 7, so we dont return 0 and end up starting in 3189 * state 1 (DRAIN). 3190 */ 3191 ret_val = BBR_SUBSTATE_COUNT - 1 - ran; 3192 /* Set an epoch */ 3193 if ((cts - bbr->r_ctl.rc_rcv_epoch_start) >= bbr_get_rtt(bbr, BBR_RTT_PROP)) 3194 bbr_set_epoch(bbr, cts, __LINE__); 3195 3196 bbr->r_ctl.bbr_lost_at_state = bbr->r_ctl.rc_lost; 3197 return (ret_val); 3198 } 3199 3200 static void 3201 bbr_lt_bw_sampling(struct tcp_bbr *bbr, uint32_t cts, int32_t loss_detected) 3202 { 3203 uint32_t diff, d_time; 3204 uint64_t del_time, bw, lost, delivered; 3205 3206 if (bbr->r_use_policer == 0) 3207 return; 3208 if (bbr->rc_lt_use_bw) { 3209 /* We are using lt bw do we stop yet? */ 3210 diff = bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_lt_epoch_use; 3211 if (diff > bbr_lt_bw_max_rtts) { 3212 /* Reset it all */ 3213 reset_all: 3214 bbr_reset_lt_bw_sampling(bbr, cts); 3215 if (bbr->rc_filled_pipe) { 3216 bbr_set_epoch(bbr, cts, __LINE__); 3217 bbr->rc_bbr_substate = bbr_pick_probebw_substate(bbr, cts); 3218 bbr_substate_change(bbr, cts, __LINE__, 0); 3219 bbr->rc_bbr_state = BBR_STATE_PROBE_BW; 3220 bbr_log_type_statechange(bbr, cts, __LINE__); 3221 } else { 3222 /* 3223 * This should not happen really 3224 * unless we remove the startup/drain 3225 * restrictions above. 3226 */ 3227 bbr->rc_bbr_state = BBR_STATE_STARTUP; 3228 bbr_set_epoch(bbr, cts, __LINE__); 3229 bbr->r_ctl.rc_bbr_state_time = cts; 3230 bbr->r_ctl.rc_lost_at_startup = bbr->r_ctl.rc_lost; 3231 bbr->r_ctl.rc_bbr_hptsi_gain = bbr->r_ctl.rc_startup_pg; 3232 bbr->r_ctl.rc_bbr_cwnd_gain = bbr->r_ctl.rc_startup_pg; 3233 bbr_set_state_target(bbr, __LINE__); 3234 bbr_log_type_statechange(bbr, cts, __LINE__); 3235 } 3236 /* reason 0 is to stop using lt-bw */ 3237 bbr_log_type_ltbw(bbr, cts, 0, 0, 0, 0, 0); 3238 return; 3239 } 3240 if (bbr_lt_intvl_fp == 0) { 3241 /* Not doing false-postive detection */ 3242 return; 3243 } 3244 /* False positive detection */ 3245 if (diff == bbr_lt_intvl_fp) { 3246 /* At bbr_lt_intvl_fp we record the lost */ 3247 bbr->r_ctl.rc_lt_del = bbr->r_ctl.rc_delivered; 3248 bbr->r_ctl.rc_lt_lost = bbr->r_ctl.rc_lost; 3249 } else if (diff > (bbr_lt_intvl_min_rtts + bbr_lt_intvl_fp)) { 3250 /* Now is our loss rate still high? */ 3251 lost = bbr->r_ctl.rc_lost - bbr->r_ctl.rc_lt_lost; 3252 delivered = bbr->r_ctl.rc_delivered - bbr->r_ctl.rc_lt_del; 3253 if ((delivered == 0) || 3254 (((lost * 1000)/delivered) < bbr_lt_fd_thresh)) { 3255 /* No still below our threshold */ 3256 bbr_log_type_ltbw(bbr, cts, 7, lost, delivered, 0, 0); 3257 } else { 3258 /* Yikes its still high, it must be a false positive */ 3259 bbr_log_type_ltbw(bbr, cts, 8, lost, delivered, 0, 0); 3260 goto reset_all; 3261 } 3262 } 3263 return; 3264 } 3265 /* 3266 * Wait for the first loss before sampling, to let the policer 3267 * exhaust its tokens and estimate the steady-state rate allowed by 3268 * the policer. Starting samples earlier includes bursts that 3269 * over-estimate the bw. 3270 */ 3271 if (bbr->rc_lt_is_sampling == 0) { 3272 /* reason 1 is to begin doing the sampling */ 3273 if (loss_detected == 0) 3274 return; 3275 bbr_reset_lt_bw_interval(bbr, cts); 3276 bbr->rc_lt_is_sampling = 1; 3277 bbr_log_type_ltbw(bbr, cts, 1, 0, 0, 0, 0); 3278 return; 3279 } 3280 /* Now how long were we delivering long term last> */ 3281 if (TSTMP_GEQ(bbr->r_ctl.rc_del_time, bbr->r_ctl.rc_lt_time)) 3282 d_time = bbr->r_ctl.rc_del_time - bbr->r_ctl.rc_lt_time; 3283 else 3284 d_time = 0; 3285 3286 /* To avoid underestimates, reset sampling if we run out of data. */ 3287 if (bbr->r_ctl.r_app_limited_until) { 3288 /* Can not measure in app-limited state */ 3289 bbr_reset_lt_bw_sampling(bbr, cts); 3290 /* reason 2 is to reset sampling due to app limits */ 3291 bbr_log_type_ltbw(bbr, cts, 2, 0, 0, 0, d_time); 3292 return; 3293 } 3294 diff = bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_lt_epoch; 3295 if (diff < bbr_lt_intvl_min_rtts) { 3296 /* 3297 * need more samples (we don't 3298 * start on a round like linux so 3299 * we need 1 more). 3300 */ 3301 /* 6 is not_enough time or no-loss */ 3302 bbr_log_type_ltbw(bbr, cts, 6, 0, 0, 0, d_time); 3303 return; 3304 } 3305 if (diff > (4 * bbr_lt_intvl_min_rtts)) { 3306 /* 3307 * For now if we wait too long, reset all sampling. We need 3308 * to do some research here, its possible that we should 3309 * base this on how much loss as occurred.. something like 3310 * if its under 10% (or some thresh) reset all otherwise 3311 * don't. Thats for phase II I guess. 3312 */ 3313 bbr_reset_lt_bw_sampling(bbr, cts); 3314 /* reason 3 is to reset sampling due too long of sampling */ 3315 bbr_log_type_ltbw(bbr, cts, 3, 0, 0, 0, d_time); 3316 return; 3317 } 3318 /* 3319 * End sampling interval when a packet is lost, so we estimate the 3320 * policer tokens were exhausted. Stopping the sampling before the 3321 * tokens are exhausted under-estimates the policed rate. 3322 */ 3323 if (loss_detected == 0) { 3324 /* 6 is not_enough time or no-loss */ 3325 bbr_log_type_ltbw(bbr, cts, 6, 0, 0, 0, d_time); 3326 return; 3327 } 3328 /* Calculate packets lost and delivered in sampling interval. */ 3329 lost = bbr->r_ctl.rc_lost - bbr->r_ctl.rc_lt_lost; 3330 delivered = bbr->r_ctl.rc_delivered - bbr->r_ctl.rc_lt_del; 3331 if ((delivered == 0) || 3332 (((lost * 1000)/delivered) < bbr_lt_loss_thresh)) { 3333 bbr_log_type_ltbw(bbr, cts, 6, lost, delivered, 0, d_time); 3334 return; 3335 } 3336 if (d_time < 1000) { 3337 /* Not enough time. wait */ 3338 /* 6 is not_enough time or no-loss */ 3339 bbr_log_type_ltbw(bbr, cts, 6, 0, 0, 0, d_time); 3340 return; 3341 } 3342 if (d_time >= (0xffffffff / USECS_IN_MSEC)) { 3343 /* Too long */ 3344 bbr_reset_lt_bw_sampling(bbr, cts); 3345 /* reason 3 is to reset sampling due too long of sampling */ 3346 bbr_log_type_ltbw(bbr, cts, 3, 0, 0, 0, d_time); 3347 return; 3348 } 3349 del_time = d_time; 3350 bw = delivered; 3351 bw *= (uint64_t)USECS_IN_SECOND; 3352 bw /= del_time; 3353 bbr_lt_bw_samp_done(bbr, bw, cts, d_time); 3354 } 3355 3356 /* 3357 * Allocate a sendmap from our zone. 3358 */ 3359 static struct bbr_sendmap * 3360 bbr_alloc(struct tcp_bbr *bbr) 3361 { 3362 struct bbr_sendmap *rsm; 3363 3364 BBR_STAT_INC(bbr_to_alloc); 3365 rsm = uma_zalloc(bbr_zone, (M_NOWAIT | M_ZERO)); 3366 if (rsm) { 3367 bbr->r_ctl.rc_num_maps_alloced++; 3368 return (rsm); 3369 } 3370 if (bbr->r_ctl.rc_free_cnt) { 3371 BBR_STAT_INC(bbr_to_alloc_emerg); 3372 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_free); 3373 TAILQ_REMOVE(&bbr->r_ctl.rc_free, rsm, r_next); 3374 bbr->r_ctl.rc_free_cnt--; 3375 return (rsm); 3376 } 3377 BBR_STAT_INC(bbr_to_alloc_failed); 3378 return (NULL); 3379 } 3380 3381 static struct bbr_sendmap * 3382 bbr_alloc_full_limit(struct tcp_bbr *bbr) 3383 { 3384 if ((bbr_tcp_map_entries_limit > 0) && 3385 (bbr->r_ctl.rc_num_maps_alloced >= bbr_tcp_map_entries_limit)) { 3386 BBR_STAT_INC(bbr_alloc_limited); 3387 if (!bbr->alloc_limit_reported) { 3388 bbr->alloc_limit_reported = 1; 3389 BBR_STAT_INC(bbr_alloc_limited_conns); 3390 } 3391 return (NULL); 3392 } 3393 return (bbr_alloc(bbr)); 3394 } 3395 3396 3397 /* wrapper to allocate a sendmap entry, subject to a specific limit */ 3398 static struct bbr_sendmap * 3399 bbr_alloc_limit(struct tcp_bbr *bbr, uint8_t limit_type) 3400 { 3401 struct bbr_sendmap *rsm; 3402 3403 if (limit_type) { 3404 /* currently there is only one limit type */ 3405 if (bbr_tcp_map_split_limit > 0 && 3406 bbr->r_ctl.rc_num_split_allocs >= bbr_tcp_map_split_limit) { 3407 BBR_STAT_INC(bbr_split_limited); 3408 if (!bbr->alloc_limit_reported) { 3409 bbr->alloc_limit_reported = 1; 3410 BBR_STAT_INC(bbr_alloc_limited_conns); 3411 } 3412 return (NULL); 3413 } 3414 } 3415 3416 /* allocate and mark in the limit type, if set */ 3417 rsm = bbr_alloc(bbr); 3418 if (rsm != NULL && limit_type) { 3419 rsm->r_limit_type = limit_type; 3420 bbr->r_ctl.rc_num_split_allocs++; 3421 } 3422 return (rsm); 3423 } 3424 3425 static void 3426 bbr_free(struct tcp_bbr *bbr, struct bbr_sendmap *rsm) 3427 { 3428 if (rsm->r_limit_type) { 3429 /* currently there is only one limit type */ 3430 bbr->r_ctl.rc_num_split_allocs--; 3431 } 3432 if (rsm->r_is_smallmap) 3433 bbr->r_ctl.rc_num_small_maps_alloced--; 3434 if (bbr->r_ctl.rc_tlp_send == rsm) 3435 bbr->r_ctl.rc_tlp_send = NULL; 3436 if (bbr->r_ctl.rc_resend == rsm) { 3437 bbr->r_ctl.rc_resend = NULL; 3438 } 3439 if (bbr->r_ctl.rc_next == rsm) 3440 bbr->r_ctl.rc_next = NULL; 3441 if (bbr->r_ctl.rc_sacklast == rsm) 3442 bbr->r_ctl.rc_sacklast = NULL; 3443 if (bbr->r_ctl.rc_free_cnt < bbr_min_req_free) { 3444 memset(rsm, 0, sizeof(struct bbr_sendmap)); 3445 TAILQ_INSERT_TAIL(&bbr->r_ctl.rc_free, rsm, r_next); 3446 rsm->r_limit_type = 0; 3447 bbr->r_ctl.rc_free_cnt++; 3448 return; 3449 } 3450 bbr->r_ctl.rc_num_maps_alloced--; 3451 uma_zfree(bbr_zone, rsm); 3452 } 3453 3454 /* 3455 * Returns the BDP. 3456 */ 3457 static uint64_t 3458 bbr_get_bw_delay_prod(uint64_t rtt, uint64_t bw) { 3459 /* 3460 * Calculate the bytes in flight needed given the bw (in bytes per 3461 * second) and the specifyed rtt in useconds. We need to put out the 3462 * returned value per RTT to match that rate. Gain will normaly 3463 * raise it up from there. 3464 * 3465 * This should not overflow as long as the bandwidth is below 1 3466 * TByte per second (bw < 10**12 = 2**40) and the rtt is smaller 3467 * than 1000 seconds (rtt < 10**3 * 10**6 = 10**9 = 2**30). 3468 */ 3469 uint64_t usec_per_sec; 3470 3471 usec_per_sec = USECS_IN_SECOND; 3472 return ((rtt * bw) / usec_per_sec); 3473 } 3474 3475 /* 3476 * Return the initial cwnd. 3477 */ 3478 static uint32_t 3479 bbr_initial_cwnd(struct tcp_bbr *bbr, struct tcpcb *tp) 3480 { 3481 uint32_t i_cwnd; 3482 3483 if (bbr->rc_init_win) { 3484 i_cwnd = bbr->rc_init_win * tp->t_maxseg; 3485 } else if (V_tcp_initcwnd_segments) 3486 i_cwnd = min((V_tcp_initcwnd_segments * tp->t_maxseg), 3487 max(2 * tp->t_maxseg, 14600)); 3488 else if (V_tcp_do_rfc3390) 3489 i_cwnd = min(4 * tp->t_maxseg, 3490 max(2 * tp->t_maxseg, 4380)); 3491 else { 3492 /* Per RFC5681 Section 3.1 */ 3493 if (tp->t_maxseg > 2190) 3494 i_cwnd = 2 * tp->t_maxseg; 3495 else if (tp->t_maxseg > 1095) 3496 i_cwnd = 3 * tp->t_maxseg; 3497 else 3498 i_cwnd = 4 * tp->t_maxseg; 3499 } 3500 return (i_cwnd); 3501 } 3502 3503 /* 3504 * Given a specified gain, return the target 3505 * cwnd based on that gain. 3506 */ 3507 static uint32_t 3508 bbr_get_raw_target_cwnd(struct tcp_bbr *bbr, uint32_t gain, uint64_t bw) 3509 { 3510 uint64_t bdp, rtt; 3511 uint32_t cwnd; 3512 3513 if ((get_filter_value_small(&bbr->r_ctl.rc_rttprop) == 0xffffffff) || 3514 (bbr_get_full_bw(bbr) == 0)) { 3515 /* No measurements yet */ 3516 return (bbr_initial_cwnd(bbr, bbr->rc_tp)); 3517 } 3518 /* 3519 * Get bytes per RTT needed (rttProp is normally in 3520 * bbr_cwndtarget_rtt_touse) 3521 */ 3522 rtt = bbr_get_rtt(bbr, bbr_cwndtarget_rtt_touse); 3523 /* Get the bdp from the two values */ 3524 bdp = bbr_get_bw_delay_prod(rtt, bw); 3525 /* Now apply the gain */ 3526 cwnd = (uint32_t)(((bdp * ((uint64_t)gain)) + (uint64_t)(BBR_UNIT - 1)) / ((uint64_t)BBR_UNIT)); 3527 3528 return (cwnd); 3529 } 3530 3531 static uint32_t 3532 bbr_get_target_cwnd(struct tcp_bbr *bbr, uint64_t bw, uint32_t gain) 3533 { 3534 uint32_t cwnd, mss; 3535 3536 mss = min((bbr->rc_tp->t_maxseg - bbr->rc_last_options), bbr->r_ctl.rc_pace_max_segs); 3537 /* Get the base cwnd with gain rounded to a mss */ 3538 cwnd = roundup(bbr_get_raw_target_cwnd(bbr, bw, gain), mss); 3539 /* 3540 * Add in N (2 default since we do not have a 3541 * fq layer to trap packets in) quanta's per the I-D 3542 * section 4.2.3.2 quanta adjust. 3543 */ 3544 cwnd += (bbr_quanta * bbr->r_ctl.rc_pace_max_segs); 3545 if (bbr->rc_use_google) { 3546 if((bbr->rc_bbr_state == BBR_STATE_PROBE_BW) && 3547 (bbr_state_val(bbr) == BBR_SUB_GAIN)) { 3548 /* 3549 * The linux implementation adds 3550 * an extra 2 x mss in gain cycle which 3551 * is documented no-where except in the code. 3552 * so we add more for Neal undocumented feature 3553 */ 3554 cwnd += 2 * mss; 3555 } 3556 if ((cwnd / mss) & 0x1) { 3557 /* Round up for odd num mss */ 3558 cwnd += mss; 3559 } 3560 } 3561 /* Are we below the min cwnd? */ 3562 if (cwnd < get_min_cwnd(bbr)) 3563 return (get_min_cwnd(bbr)); 3564 return (cwnd); 3565 } 3566 3567 static uint16_t 3568 bbr_gain_adjust(struct tcp_bbr *bbr, uint16_t gain) 3569 { 3570 if (gain < 1) 3571 gain = 1; 3572 return (gain); 3573 } 3574 3575 static uint32_t 3576 bbr_get_header_oh(struct tcp_bbr *bbr) 3577 { 3578 int seg_oh; 3579 3580 seg_oh = 0; 3581 if (bbr->r_ctl.rc_inc_tcp_oh) { 3582 /* Do we include TCP overhead? */ 3583 seg_oh = (bbr->rc_last_options + sizeof(struct tcphdr)); 3584 } 3585 if (bbr->r_ctl.rc_inc_ip_oh) { 3586 /* Do we include IP overhead? */ 3587 #ifdef INET6 3588 if (bbr->r_is_v6) 3589 seg_oh += sizeof(struct ip6_hdr); 3590 else 3591 #endif 3592 #ifdef INET 3593 seg_oh += sizeof(struct ip); 3594 #endif 3595 } 3596 if (bbr->r_ctl.rc_inc_enet_oh) { 3597 /* Do we include the ethernet overhead? */ 3598 seg_oh += sizeof(struct ether_header); 3599 } 3600 return(seg_oh); 3601 } 3602 3603 3604 static uint32_t 3605 bbr_get_pacing_length(struct tcp_bbr *bbr, uint16_t gain, uint32_t useconds_time, uint64_t bw) 3606 { 3607 uint64_t divor, res, tim; 3608 3609 if (useconds_time == 0) 3610 return (0); 3611 gain = bbr_gain_adjust(bbr, gain); 3612 divor = (uint64_t)USECS_IN_SECOND * (uint64_t)BBR_UNIT; 3613 tim = useconds_time; 3614 res = (tim * bw * gain) / divor; 3615 if (res == 0) 3616 res = 1; 3617 return ((uint32_t)res); 3618 } 3619 3620 /* 3621 * Given a gain and a length return the delay in useconds that 3622 * should be used to evenly space out packets 3623 * on the connection (based on the gain factor). 3624 */ 3625 static uint32_t 3626 bbr_get_pacing_delay(struct tcp_bbr *bbr, uint16_t gain, int32_t len, uint32_t cts, int nolog) 3627 { 3628 uint64_t bw, lentim, res; 3629 uint32_t usecs, srtt, over = 0; 3630 uint32_t seg_oh, num_segs, maxseg; 3631 3632 if (len == 0) 3633 return (0); 3634 3635 maxseg = bbr->rc_tp->t_maxseg - bbr->rc_last_options; 3636 num_segs = (len + maxseg - 1) / maxseg; 3637 if (bbr->rc_use_google == 0) { 3638 seg_oh = bbr_get_header_oh(bbr); 3639 len += (num_segs * seg_oh); 3640 } 3641 gain = bbr_gain_adjust(bbr, gain); 3642 bw = bbr_get_bw(bbr); 3643 if (bbr->rc_use_google) { 3644 uint64_t cbw; 3645 3646 /* 3647 * Reduce the b/w by the google discount 3648 * factor 10 = 1%. 3649 */ 3650 cbw = bw * (uint64_t)(1000 - bbr->r_ctl.bbr_google_discount); 3651 cbw /= (uint64_t)1000; 3652 /* We don't apply a discount if it results in 0 */ 3653 if (cbw > 0) 3654 bw = cbw; 3655 } 3656 lentim = ((uint64_t)len * 3657 (uint64_t)USECS_IN_SECOND * 3658 (uint64_t)BBR_UNIT); 3659 res = lentim / ((uint64_t)gain * bw); 3660 if (res == 0) 3661 res = 1; 3662 usecs = (uint32_t)res; 3663 srtt = bbr_get_rtt(bbr, BBR_SRTT); 3664 if (bbr_hptsi_max_mul && bbr_hptsi_max_div && 3665 (bbr->rc_use_google == 0) && 3666 (usecs > ((srtt * bbr_hptsi_max_mul) / bbr_hptsi_max_div))) { 3667 /* 3668 * We cannot let the delay be more than 1/2 the srtt time. 3669 * Otherwise we cannot pace out or send properly. 3670 */ 3671 over = usecs = (srtt * bbr_hptsi_max_mul) / bbr_hptsi_max_div; 3672 BBR_STAT_INC(bbr_hpts_min_time); 3673 } 3674 if (!nolog) 3675 bbr_log_pacing_delay_calc(bbr, gain, len, cts, usecs, bw, over, 1); 3676 return (usecs); 3677 } 3678 3679 static void 3680 bbr_ack_received(struct tcpcb *tp, struct tcp_bbr *bbr, struct tcphdr *th, uint32_t bytes_this_ack, 3681 uint32_t sack_changed, uint32_t prev_acked, int32_t line, uint32_t losses) 3682 { 3683 INP_WLOCK_ASSERT(tp->t_inpcb); 3684 uint64_t bw; 3685 uint32_t cwnd, target_cwnd, saved_bytes, maxseg; 3686 int32_t meth; 3687 3688 #ifdef NETFLIX_STATS 3689 if ((tp->t_flags & TF_GPUTINPROG) && 3690 SEQ_GEQ(th->th_ack, tp->gput_ack)) { 3691 /* 3692 * Strech acks and compressed acks will cause this to 3693 * oscillate but we are doing it the same way as the main 3694 * stack so it will be compariable (though possibly not 3695 * ideal). 3696 */ 3697 int32_t cgput; 3698 int64_t gput, time_stamp; 3699 3700 gput = (int64_t) (th->th_ack - tp->gput_seq) * 8; 3701 time_stamp = max(1, ((bbr->r_ctl.rc_rcvtime - tp->gput_ts) / 1000)); 3702 cgput = gput / time_stamp; 3703 stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_GPUT, 3704 cgput); 3705 if (tp->t_stats_gput_prev > 0) 3706 stats_voi_update_abs_s32(tp->t_stats, 3707 VOI_TCP_GPUT_ND, 3708 ((gput - tp->t_stats_gput_prev) * 100) / 3709 tp->t_stats_gput_prev); 3710 tp->t_flags &= ~TF_GPUTINPROG; 3711 tp->t_stats_gput_prev = cgput; 3712 } 3713 #endif 3714 if ((bbr->rc_bbr_state == BBR_STATE_PROBE_RTT) && 3715 ((bbr->r_ctl.bbr_rttprobe_gain_val == 0) || bbr->rc_use_google)) { 3716 /* We don't change anything in probe-rtt */ 3717 return; 3718 } 3719 maxseg = tp->t_maxseg - bbr->rc_last_options; 3720 saved_bytes = bytes_this_ack; 3721 bytes_this_ack += sack_changed; 3722 if (bytes_this_ack > prev_acked) { 3723 bytes_this_ack -= prev_acked; 3724 /* 3725 * A byte ack'd gives us a full mss 3726 * to be like linux i.e. they count packets. 3727 */ 3728 if ((bytes_this_ack < maxseg) && bbr->rc_use_google) 3729 bytes_this_ack = maxseg; 3730 } else { 3731 /* Unlikely */ 3732 bytes_this_ack = 0; 3733 } 3734 cwnd = tp->snd_cwnd; 3735 bw = get_filter_value(&bbr->r_ctl.rc_delrate); 3736 if (bw) 3737 target_cwnd = bbr_get_target_cwnd(bbr, 3738 bw, 3739 (uint32_t)bbr->r_ctl.rc_bbr_cwnd_gain); 3740 else 3741 target_cwnd = bbr_initial_cwnd(bbr, bbr->rc_tp); 3742 if (IN_RECOVERY(tp->t_flags) && 3743 (bbr->bbr_prev_in_rec == 0)) { 3744 /* 3745 * We are entering recovery and 3746 * thus packet conservation. 3747 */ 3748 bbr->pkt_conservation = 1; 3749 bbr->r_ctl.rc_recovery_start = bbr->r_ctl.rc_rcvtime; 3750 cwnd = ctf_flight_size(tp, 3751 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)) + 3752 bytes_this_ack; 3753 } 3754 if (IN_RECOVERY(tp->t_flags)) { 3755 uint32_t flight; 3756 3757 bbr->bbr_prev_in_rec = 1; 3758 if (cwnd > losses) { 3759 cwnd -= losses; 3760 if (cwnd < maxseg) 3761 cwnd = maxseg; 3762 } else 3763 cwnd = maxseg; 3764 flight = ctf_flight_size(tp, 3765 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 3766 bbr_log_type_cwndupd(bbr, flight, 0, 3767 losses, 10, 0, 0, line); 3768 if (bbr->pkt_conservation) { 3769 uint32_t time_in; 3770 3771 if (TSTMP_GEQ(bbr->r_ctl.rc_rcvtime, bbr->r_ctl.rc_recovery_start)) 3772 time_in = bbr->r_ctl.rc_rcvtime - bbr->r_ctl.rc_recovery_start; 3773 else 3774 time_in = 0; 3775 3776 if (time_in >= bbr_get_rtt(bbr, BBR_RTT_PROP)) { 3777 /* Clear packet conservation after an rttProp */ 3778 bbr->pkt_conservation = 0; 3779 } else { 3780 if ((flight + bytes_this_ack) > cwnd) 3781 cwnd = flight + bytes_this_ack; 3782 if (cwnd < get_min_cwnd(bbr)) 3783 cwnd = get_min_cwnd(bbr); 3784 tp->snd_cwnd = cwnd; 3785 bbr_log_type_cwndupd(bbr, saved_bytes, sack_changed, 3786 prev_acked, 1, target_cwnd, th->th_ack, line); 3787 return; 3788 } 3789 } 3790 } else 3791 bbr->bbr_prev_in_rec = 0; 3792 if ((bbr->rc_use_google == 0) && bbr->r_ctl.restrict_growth) { 3793 bbr->r_ctl.restrict_growth--; 3794 if (bytes_this_ack > maxseg) 3795 bytes_this_ack = maxseg; 3796 } 3797 if (bbr->rc_filled_pipe) { 3798 /* 3799 * Here we have exited startup and filled the pipe. We will 3800 * thus allow the cwnd to shrink to the target. We hit here 3801 * mostly. 3802 */ 3803 uint32_t s_cwnd; 3804 3805 meth = 2; 3806 s_cwnd = min((cwnd + bytes_this_ack), target_cwnd); 3807 if (s_cwnd > cwnd) 3808 cwnd = s_cwnd; 3809 else if (bbr_cwnd_may_shrink || bbr->rc_use_google || bbr->rc_no_pacing) 3810 cwnd = s_cwnd; 3811 } else { 3812 /* 3813 * Here we are still in startup, we increase cwnd by what 3814 * has been acked. 3815 */ 3816 if ((cwnd < target_cwnd) || 3817 (bbr->rc_past_init_win == 0)) { 3818 meth = 3; 3819 cwnd += bytes_this_ack; 3820 } else { 3821 /* 3822 * Method 4 means we are at target so no gain in 3823 * startup and past the initial window. 3824 */ 3825 meth = 4; 3826 } 3827 } 3828 tp->snd_cwnd = max(cwnd, get_min_cwnd(bbr)); 3829 bbr_log_type_cwndupd(bbr, saved_bytes, sack_changed, prev_acked, meth, target_cwnd, th->th_ack, line); 3830 } 3831 3832 static void 3833 tcp_bbr_partialack(struct tcpcb *tp) 3834 { 3835 struct tcp_bbr *bbr; 3836 3837 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 3838 INP_WLOCK_ASSERT(tp->t_inpcb); 3839 if (ctf_flight_size(tp, 3840 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)) <= 3841 tp->snd_cwnd) { 3842 bbr->r_wanted_output = 1; 3843 } 3844 } 3845 3846 static void 3847 bbr_post_recovery(struct tcpcb *tp) 3848 { 3849 struct tcp_bbr *bbr; 3850 uint32_t flight; 3851 3852 INP_WLOCK_ASSERT(tp->t_inpcb); 3853 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 3854 /* 3855 * Here we just exit recovery. 3856 */ 3857 EXIT_RECOVERY(tp->t_flags); 3858 /* Lock in our b/w reduction for the specified number of pkt-epochs */ 3859 bbr->r_recovery_bw = 0; 3860 tp->snd_recover = tp->snd_una; 3861 tcp_bbr_tso_size_check(bbr, bbr->r_ctl.rc_rcvtime); 3862 bbr->pkt_conservation = 0; 3863 if (bbr->rc_use_google == 0) { 3864 /* 3865 * For non-google mode lets 3866 * go ahead and make sure we clear 3867 * the recovery state so if we 3868 * bounce back in to recovery we 3869 * will do PC. 3870 */ 3871 bbr->bbr_prev_in_rec = 0; 3872 } 3873 bbr_log_type_exit_rec(bbr); 3874 if (bbr->rc_bbr_state != BBR_STATE_PROBE_RTT) { 3875 tp->snd_cwnd = max(tp->snd_cwnd, bbr->r_ctl.rc_cwnd_on_ent); 3876 bbr_log_type_cwndupd(bbr, 0, 0, 0, 15, 0, 0, __LINE__); 3877 } else { 3878 /* For probe-rtt case lets fix up its saved_cwnd */ 3879 if (bbr->r_ctl.rc_saved_cwnd < bbr->r_ctl.rc_cwnd_on_ent) { 3880 bbr->r_ctl.rc_saved_cwnd = bbr->r_ctl.rc_cwnd_on_ent; 3881 bbr_log_type_cwndupd(bbr, 0, 0, 0, 16, 0, 0, __LINE__); 3882 } 3883 } 3884 flight = ctf_flight_size(tp, 3885 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 3886 if ((bbr->rc_use_google == 0) && 3887 bbr_do_red) { 3888 uint64_t val, lr2use; 3889 uint32_t maxseg, newcwnd, acks_inflight, ratio, cwnd; 3890 uint32_t *cwnd_p; 3891 3892 if (bbr_get_rtt(bbr, BBR_SRTT)) { 3893 val = ((uint64_t)bbr_get_rtt(bbr, BBR_RTT_PROP) * (uint64_t)1000); 3894 val /= bbr_get_rtt(bbr, BBR_SRTT); 3895 ratio = (uint32_t)val; 3896 } else 3897 ratio = 1000; 3898 3899 bbr_log_type_cwndupd(bbr, bbr_red_mul, bbr_red_div, 3900 bbr->r_ctl.recovery_lr, 21, 3901 ratio, 3902 bbr->r_ctl.rc_red_cwnd_pe, 3903 __LINE__); 3904 if ((ratio < bbr_do_red) || (bbr_do_red == 0)) 3905 goto done; 3906 if (((bbr->rc_bbr_state == BBR_STATE_PROBE_RTT) && 3907 bbr_prtt_slam_cwnd) || 3908 (bbr_sub_drain_slam_cwnd && 3909 (bbr->rc_bbr_state == BBR_STATE_PROBE_BW) && 3910 bbr->rc_hit_state_1 && 3911 (bbr_state_val(bbr) == BBR_SUB_DRAIN)) || 3912 ((bbr->rc_bbr_state == BBR_STATE_DRAIN) && 3913 bbr_slam_cwnd_in_main_drain)) { 3914 /* 3915 * Here we must poke at the saved cwnd 3916 * as well as the cwnd. 3917 */ 3918 cwnd = bbr->r_ctl.rc_saved_cwnd; 3919 cwnd_p = &bbr->r_ctl.rc_saved_cwnd; 3920 } else { 3921 cwnd = tp->snd_cwnd; 3922 cwnd_p = &tp->snd_cwnd; 3923 } 3924 maxseg = tp->t_maxseg - bbr->rc_last_options; 3925 /* Add the overall lr with the recovery lr */ 3926 if (bbr->r_ctl.rc_lost == 0) 3927 lr2use = 0; 3928 else if (bbr->r_ctl.rc_delivered == 0) 3929 lr2use = 1000; 3930 else { 3931 lr2use = bbr->r_ctl.rc_lost * 1000; 3932 lr2use /= bbr->r_ctl.rc_delivered; 3933 } 3934 lr2use += bbr->r_ctl.recovery_lr; 3935 acks_inflight = (flight / (maxseg * 2)); 3936 if (bbr_red_scale) { 3937 lr2use *= bbr_get_rtt(bbr, BBR_SRTT); 3938 lr2use /= bbr_red_scale; 3939 if ((bbr_red_growth_restrict) && 3940 ((bbr_get_rtt(bbr, BBR_SRTT)/bbr_red_scale) > 1)) 3941 bbr->r_ctl.restrict_growth += acks_inflight; 3942 } 3943 if (lr2use) { 3944 val = (uint64_t)cwnd * lr2use; 3945 val /= 1000; 3946 if (cwnd > val) 3947 newcwnd = roundup((cwnd - val), maxseg); 3948 else 3949 newcwnd = maxseg; 3950 } else { 3951 val = (uint64_t)cwnd * (uint64_t)bbr_red_mul; 3952 val /= (uint64_t)bbr_red_div; 3953 newcwnd = roundup((uint32_t)val, maxseg); 3954 } 3955 /* with standard delayed acks how many acks can I expect? */ 3956 if (bbr_drop_limit == 0) { 3957 /* 3958 * Anticpate how much we will 3959 * raise the cwnd based on the acks. 3960 */ 3961 if ((newcwnd + (acks_inflight * maxseg)) < get_min_cwnd(bbr)) { 3962 /* We do enforce the min (with the acks) */ 3963 newcwnd = (get_min_cwnd(bbr) - acks_inflight); 3964 } 3965 } else { 3966 /* 3967 * A strict drop limit of N is is inplace 3968 */ 3969 if (newcwnd < (bbr_drop_limit * maxseg)) { 3970 newcwnd = bbr_drop_limit * maxseg; 3971 } 3972 } 3973 /* For the next N acks do we restrict the growth */ 3974 *cwnd_p = newcwnd; 3975 if (tp->snd_cwnd > newcwnd) 3976 tp->snd_cwnd = newcwnd; 3977 bbr_log_type_cwndupd(bbr, bbr_red_mul, bbr_red_div, val, 22, 3978 (uint32_t)lr2use, 3979 bbr_get_rtt(bbr, BBR_SRTT), __LINE__); 3980 bbr->r_ctl.rc_red_cwnd_pe = bbr->r_ctl.rc_pkt_epoch; 3981 } 3982 done: 3983 bbr->r_ctl.recovery_lr = 0; 3984 if (flight <= tp->snd_cwnd) { 3985 bbr->r_wanted_output = 1; 3986 } 3987 tcp_bbr_tso_size_check(bbr, bbr->r_ctl.rc_rcvtime); 3988 } 3989 3990 static void 3991 bbr_setup_red_bw(struct tcp_bbr *bbr, uint32_t cts) 3992 { 3993 bbr->r_ctl.red_bw = get_filter_value(&bbr->r_ctl.rc_delrate); 3994 /* Limit the drop in b/w to 1/2 our current filter. */ 3995 if (bbr->r_ctl.red_bw > bbr->r_ctl.rc_bbr_cur_del_rate) 3996 bbr->r_ctl.red_bw = bbr->r_ctl.rc_bbr_cur_del_rate; 3997 if (bbr->r_ctl.red_bw < (get_filter_value(&bbr->r_ctl.rc_delrate) / 2)) 3998 bbr->r_ctl.red_bw = get_filter_value(&bbr->r_ctl.rc_delrate) / 2; 3999 tcp_bbr_tso_size_check(bbr, cts); 4000 } 4001 4002 static void 4003 bbr_cong_signal(struct tcpcb *tp, struct tcphdr *th, uint32_t type, struct bbr_sendmap *rsm) 4004 { 4005 struct tcp_bbr *bbr; 4006 4007 INP_WLOCK_ASSERT(tp->t_inpcb); 4008 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 4009 switch (type) { 4010 case CC_NDUPACK: 4011 if (!IN_RECOVERY(tp->t_flags)) { 4012 tp->snd_recover = tp->snd_max; 4013 /* Start a new epoch */ 4014 bbr_set_pktepoch(bbr, bbr->r_ctl.rc_rcvtime, __LINE__); 4015 if (bbr->rc_lt_is_sampling || bbr->rc_lt_use_bw) { 4016 /* 4017 * Move forward the lt epoch 4018 * so it won't count the truncated 4019 * epoch. 4020 */ 4021 bbr->r_ctl.rc_lt_epoch++; 4022 } 4023 if (bbr->rc_bbr_state == BBR_STATE_STARTUP) { 4024 /* 4025 * Just like the policer detection code 4026 * if we are in startup we must push 4027 * forward the last startup epoch 4028 * to hide the truncated PE. 4029 */ 4030 bbr->r_ctl.rc_bbr_last_startup_epoch++; 4031 } 4032 bbr->r_ctl.rc_cwnd_on_ent = tp->snd_cwnd; 4033 ENTER_RECOVERY(tp->t_flags); 4034 bbr->rc_tlp_rtx_out = 0; 4035 bbr->r_ctl.recovery_lr = bbr->r_ctl.rc_pkt_epoch_loss_rate; 4036 tcp_bbr_tso_size_check(bbr, bbr->r_ctl.rc_rcvtime); 4037 if (bbr->rc_inp->inp_in_hpts && 4038 ((bbr->r_ctl.rc_hpts_flags & PACE_TMR_RACK) == 0)) { 4039 /* 4040 * When we enter recovery, we need to restart 4041 * any timers. This may mean we gain an agg 4042 * early, which will be made up for at the last 4043 * rxt out. 4044 */ 4045 bbr->rc_timer_first = 1; 4046 bbr_timer_cancel(bbr, __LINE__, bbr->r_ctl.rc_rcvtime); 4047 } 4048 /* 4049 * Calculate a new cwnd based on to the current 4050 * delivery rate with no gain. We get the bdp 4051 * without gaining it up like we normally would and 4052 * we use the last cur_del_rate. 4053 */ 4054 if ((bbr->rc_use_google == 0) && 4055 (bbr->r_ctl.bbr_rttprobe_gain_val || 4056 (bbr->rc_bbr_state != BBR_STATE_PROBE_RTT))) { 4057 tp->snd_cwnd = ctf_flight_size(tp, 4058 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)) + 4059 (tp->t_maxseg - bbr->rc_last_options); 4060 if (tp->snd_cwnd < get_min_cwnd(bbr)) { 4061 /* We always gate to min cwnd */ 4062 tp->snd_cwnd = get_min_cwnd(bbr); 4063 } 4064 bbr_log_type_cwndupd(bbr, 0, 0, 0, 14, 0, 0, __LINE__); 4065 } 4066 bbr_log_type_enter_rec(bbr, rsm->r_start); 4067 } 4068 break; 4069 case CC_RTO_ERR: 4070 TCPSTAT_INC(tcps_sndrexmitbad); 4071 /* RTO was unnecessary, so reset everything. */ 4072 bbr_reset_lt_bw_sampling(bbr, bbr->r_ctl.rc_rcvtime); 4073 if (bbr->rc_bbr_state != BBR_STATE_PROBE_RTT) { 4074 tp->snd_cwnd = tp->snd_cwnd_prev; 4075 tp->snd_ssthresh = tp->snd_ssthresh_prev; 4076 tp->snd_recover = tp->snd_recover_prev; 4077 tp->snd_cwnd = max(tp->snd_cwnd, bbr->r_ctl.rc_cwnd_on_ent); 4078 bbr_log_type_cwndupd(bbr, 0, 0, 0, 13, 0, 0, __LINE__); 4079 } 4080 tp->t_badrxtwin = 0; 4081 break; 4082 } 4083 } 4084 4085 /* 4086 * Indicate whether this ack should be delayed. We can delay the ack if 4087 * following conditions are met: 4088 * - There is no delayed ack timer in progress. 4089 * - Our last ack wasn't a 0-sized window. We never want to delay 4090 * the ack that opens up a 0-sized window. 4091 * - LRO wasn't used for this segment. We make sure by checking that the 4092 * segment size is not larger than the MSS. 4093 * - Delayed acks are enabled or this is a half-synchronized T/TCP 4094 * connection. 4095 * - The data being acked is less than a full segment (a stretch ack 4096 * of more than a segment we should ack. 4097 * - nsegs is 1 (if its more than that we received more than 1 ack). 4098 */ 4099 #define DELAY_ACK(tp, bbr, nsegs) \ 4100 (((tp->t_flags & TF_RXWIN0SENT) == 0) && \ 4101 ((bbr->bbr_segs_rcvd + nsegs) < tp->t_delayed_ack) && \ 4102 (tp->t_delayed_ack || (tp->t_flags & TF_NEEDSYN))) 4103 4104 /* 4105 * Return the lowest RSM in the map of 4106 * packets still in flight that is not acked. 4107 * This should normally find on the first one 4108 * since we remove packets from the send 4109 * map after they are marked ACKED. 4110 */ 4111 static struct bbr_sendmap * 4112 bbr_find_lowest_rsm(struct tcp_bbr *bbr) 4113 { 4114 struct bbr_sendmap *rsm; 4115 4116 /* 4117 * Walk the time-order transmitted list looking for an rsm that is 4118 * not acked. This will be the one that was sent the longest time 4119 * ago that is still outstanding. 4120 */ 4121 TAILQ_FOREACH(rsm, &bbr->r_ctl.rc_tmap, r_tnext) { 4122 if (rsm->r_flags & BBR_ACKED) { 4123 continue; 4124 } 4125 goto finish; 4126 } 4127 finish: 4128 return (rsm); 4129 } 4130 4131 static struct bbr_sendmap * 4132 bbr_find_high_nonack(struct tcp_bbr *bbr, struct bbr_sendmap *rsm) 4133 { 4134 struct bbr_sendmap *prsm; 4135 4136 /* 4137 * Walk the sequence order list backward until we hit and arrive at 4138 * the highest seq not acked. In theory when this is called it 4139 * should be the last segment (which it was not). 4140 */ 4141 prsm = rsm; 4142 TAILQ_FOREACH_REVERSE_FROM(prsm, &bbr->r_ctl.rc_map, bbr_head, r_next) { 4143 if (prsm->r_flags & (BBR_ACKED | BBR_HAS_FIN)) { 4144 continue; 4145 } 4146 return (prsm); 4147 } 4148 return (NULL); 4149 } 4150 4151 /* 4152 * Returns to the caller the number of microseconds that 4153 * the packet can be outstanding before we think we 4154 * should have had an ack returned. 4155 */ 4156 static uint32_t 4157 bbr_calc_thresh_rack(struct tcp_bbr *bbr, uint32_t srtt, uint32_t cts, struct bbr_sendmap *rsm) 4158 { 4159 /* 4160 * lro is the flag we use to determine if we have seen reordering. 4161 * If it gets set we have seen reordering. The reorder logic either 4162 * works in one of two ways: 4163 * 4164 * If reorder-fade is configured, then we track the last time we saw 4165 * re-ordering occur. If we reach the point where enough time as 4166 * passed we no longer consider reordering has occuring. 4167 * 4168 * Or if reorder-face is 0, then once we see reordering we consider 4169 * the connection to alway be subject to reordering and just set lro 4170 * to 1. 4171 * 4172 * In the end if lro is non-zero we add the extra time for 4173 * reordering in. 4174 */ 4175 int32_t lro; 4176 uint32_t thresh, t_rxtcur; 4177 4178 if (srtt == 0) 4179 srtt = 1; 4180 if (bbr->r_ctl.rc_reorder_ts) { 4181 if (bbr->r_ctl.rc_reorder_fade) { 4182 if (SEQ_GEQ(cts, bbr->r_ctl.rc_reorder_ts)) { 4183 lro = cts - bbr->r_ctl.rc_reorder_ts; 4184 if (lro == 0) { 4185 /* 4186 * No time as passed since the last 4187 * reorder, mark it as reordering. 4188 */ 4189 lro = 1; 4190 } 4191 } else { 4192 /* Negative time? */ 4193 lro = 0; 4194 } 4195 if (lro > bbr->r_ctl.rc_reorder_fade) { 4196 /* Turn off reordering seen too */ 4197 bbr->r_ctl.rc_reorder_ts = 0; 4198 lro = 0; 4199 } 4200 } else { 4201 /* Reodering does not fade */ 4202 lro = 1; 4203 } 4204 } else { 4205 lro = 0; 4206 } 4207 thresh = srtt + bbr->r_ctl.rc_pkt_delay; 4208 if (lro) { 4209 /* It must be set, if not you get 1/4 rtt */ 4210 if (bbr->r_ctl.rc_reorder_shift) 4211 thresh += (srtt >> bbr->r_ctl.rc_reorder_shift); 4212 else 4213 thresh += (srtt >> 2); 4214 } else { 4215 thresh += 1000; 4216 } 4217 /* We don't let the rack timeout be above a RTO */ 4218 if ((bbr->rc_tp)->t_srtt == 0) 4219 t_rxtcur = BBR_INITIAL_RTO; 4220 else 4221 t_rxtcur = TICKS_2_USEC(bbr->rc_tp->t_rxtcur); 4222 if (thresh > t_rxtcur) { 4223 thresh = t_rxtcur; 4224 } 4225 /* And we don't want it above the RTO max either */ 4226 if (thresh > (((uint32_t)bbr->rc_max_rto_sec) * USECS_IN_SECOND)) { 4227 thresh = (((uint32_t)bbr->rc_max_rto_sec) * USECS_IN_SECOND); 4228 } 4229 bbr_log_thresh_choice(bbr, cts, thresh, lro, srtt, rsm, BBR_TO_FRM_RACK); 4230 return (thresh); 4231 } 4232 4233 /* 4234 * Return to the caller the amount of time in mico-seconds 4235 * that should be used for the TLP timer from the last 4236 * send time of this packet. 4237 */ 4238 static uint32_t 4239 bbr_calc_thresh_tlp(struct tcpcb *tp, struct tcp_bbr *bbr, 4240 struct bbr_sendmap *rsm, uint32_t srtt, 4241 uint32_t cts) 4242 { 4243 uint32_t thresh, len, maxseg, t_rxtcur; 4244 struct bbr_sendmap *prsm; 4245 4246 if (srtt == 0) 4247 srtt = 1; 4248 if (bbr->rc_tlp_threshold) 4249 thresh = srtt + (srtt / bbr->rc_tlp_threshold); 4250 else 4251 thresh = (srtt * 2); 4252 maxseg = tp->t_maxseg - bbr->rc_last_options; 4253 /* Get the previous sent packet, if any */ 4254 len = rsm->r_end - rsm->r_start; 4255 4256 /* 2.1 behavior */ 4257 prsm = TAILQ_PREV(rsm, bbr_head, r_tnext); 4258 if (prsm && (len <= maxseg)) { 4259 /* 4260 * Two packets outstanding, thresh should be (2*srtt) + 4261 * possible inter-packet delay (if any). 4262 */ 4263 uint32_t inter_gap = 0; 4264 int idx, nidx; 4265 4266 idx = rsm->r_rtr_cnt - 1; 4267 nidx = prsm->r_rtr_cnt - 1; 4268 if (TSTMP_GEQ(rsm->r_tim_lastsent[nidx], prsm->r_tim_lastsent[idx])) { 4269 /* Yes it was sent later (or at the same time) */ 4270 inter_gap = rsm->r_tim_lastsent[idx] - prsm->r_tim_lastsent[nidx]; 4271 } 4272 thresh += inter_gap; 4273 } else if (len <= maxseg) { 4274 /* 4275 * Possibly compensate for delayed-ack. 4276 */ 4277 uint32_t alt_thresh; 4278 4279 alt_thresh = srtt + (srtt / 2) + bbr_delayed_ack_time; 4280 if (alt_thresh > thresh) 4281 thresh = alt_thresh; 4282 } 4283 /* Not above the current RTO */ 4284 if (tp->t_srtt == 0) 4285 t_rxtcur = BBR_INITIAL_RTO; 4286 else 4287 t_rxtcur = TICKS_2_USEC(tp->t_rxtcur); 4288 4289 bbr_log_thresh_choice(bbr, cts, thresh, t_rxtcur, srtt, rsm, BBR_TO_FRM_TLP); 4290 /* Not above an RTO */ 4291 if (thresh > t_rxtcur) { 4292 thresh = t_rxtcur; 4293 } 4294 /* Not above a RTO max */ 4295 if (thresh > (((uint32_t)bbr->rc_max_rto_sec) * USECS_IN_SECOND)) { 4296 thresh = (((uint32_t)bbr->rc_max_rto_sec) * USECS_IN_SECOND); 4297 } 4298 /* And now apply the user TLP min */ 4299 if (thresh < bbr_tlp_min) { 4300 thresh = bbr_tlp_min; 4301 } 4302 return (thresh); 4303 } 4304 4305 /* 4306 * Return one of three RTTs to use (in microseconds). 4307 */ 4308 static __inline uint32_t 4309 bbr_get_rtt(struct tcp_bbr *bbr, int32_t rtt_type) 4310 { 4311 uint32_t f_rtt; 4312 uint32_t srtt; 4313 4314 f_rtt = get_filter_value_small(&bbr->r_ctl.rc_rttprop); 4315 if (get_filter_value_small(&bbr->r_ctl.rc_rttprop) == 0xffffffff) { 4316 /* We have no rtt at all */ 4317 if (bbr->rc_tp->t_srtt == 0) 4318 f_rtt = BBR_INITIAL_RTO; 4319 else 4320 f_rtt = (TICKS_2_USEC(bbr->rc_tp->t_srtt) >> TCP_RTT_SHIFT); 4321 /* 4322 * Since we don't know how good the rtt is apply a 4323 * delayed-ack min 4324 */ 4325 if (f_rtt < bbr_delayed_ack_time) { 4326 f_rtt = bbr_delayed_ack_time; 4327 } 4328 } 4329 /* Take the filter version or last measured pkt-rtt */ 4330 if (rtt_type == BBR_RTT_PROP) { 4331 srtt = f_rtt; 4332 } else if (rtt_type == BBR_RTT_PKTRTT) { 4333 if (bbr->r_ctl.rc_pkt_epoch_rtt) { 4334 srtt = bbr->r_ctl.rc_pkt_epoch_rtt; 4335 } else { 4336 /* No pkt rtt yet */ 4337 srtt = f_rtt; 4338 } 4339 } else if (rtt_type == BBR_RTT_RACK) { 4340 srtt = bbr->r_ctl.rc_last_rtt; 4341 /* We need to add in any internal delay for our timer */ 4342 if (bbr->rc_ack_was_delayed) 4343 srtt += bbr->r_ctl.rc_ack_hdwr_delay; 4344 } else if (rtt_type == BBR_SRTT) { 4345 srtt = (TICKS_2_USEC(bbr->rc_tp->t_srtt) >> TCP_RTT_SHIFT); 4346 } else { 4347 /* TSNH */ 4348 srtt = f_rtt; 4349 #ifdef BBR_INVARIANTS 4350 panic("Unknown rtt request type %d", rtt_type); 4351 #endif 4352 } 4353 return (srtt); 4354 } 4355 4356 static int 4357 bbr_is_lost(struct tcp_bbr *bbr, struct bbr_sendmap *rsm, uint32_t cts) 4358 { 4359 uint32_t thresh; 4360 4361 4362 thresh = bbr_calc_thresh_rack(bbr, bbr_get_rtt(bbr, BBR_RTT_RACK), 4363 cts, rsm); 4364 if ((cts - rsm->r_tim_lastsent[(rsm->r_rtr_cnt - 1)]) >= thresh) { 4365 /* It is lost (past time) */ 4366 return (1); 4367 } 4368 return (0); 4369 } 4370 4371 /* 4372 * Return a sendmap if we need to retransmit something. 4373 */ 4374 static struct bbr_sendmap * 4375 bbr_check_recovery_mode(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts) 4376 { 4377 /* 4378 * Check to see that we don't need to fall into recovery. We will 4379 * need to do so if our oldest transmit is past the time we should 4380 * have had an ack. 4381 */ 4382 4383 struct bbr_sendmap *rsm; 4384 int32_t idx; 4385 4386 if (TAILQ_EMPTY(&bbr->r_ctl.rc_map)) { 4387 /* Nothing outstanding that we know of */ 4388 return (NULL); 4389 } 4390 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_tmap); 4391 if (rsm == NULL) { 4392 /* Nothing in the transmit map */ 4393 return (NULL); 4394 } 4395 if (tp->t_flags & TF_SENTFIN) { 4396 /* Fin restricted, don't find anything once a fin is sent */ 4397 return (NULL); 4398 } 4399 if (rsm->r_flags & BBR_ACKED) { 4400 /* 4401 * Ok the first one is acked (this really should not happen 4402 * since we remove the from the tmap once they are acked) 4403 */ 4404 rsm = bbr_find_lowest_rsm(bbr); 4405 if (rsm == NULL) 4406 return (NULL); 4407 } 4408 idx = rsm->r_rtr_cnt - 1; 4409 if (SEQ_LEQ(cts, rsm->r_tim_lastsent[idx])) { 4410 /* Send timestamp is the same or less? can't be ready */ 4411 return (NULL); 4412 } 4413 /* Get our RTT time */ 4414 if (bbr_is_lost(bbr, rsm, cts) && 4415 ((rsm->r_dupack >= DUP_ACK_THRESHOLD) || 4416 (rsm->r_flags & BBR_SACK_PASSED))) { 4417 if ((rsm->r_flags & BBR_MARKED_LOST) == 0) { 4418 rsm->r_flags |= BBR_MARKED_LOST; 4419 bbr->r_ctl.rc_lost += rsm->r_end - rsm->r_start; 4420 bbr->r_ctl.rc_lost_bytes += rsm->r_end - rsm->r_start; 4421 } 4422 bbr_cong_signal(tp, NULL, CC_NDUPACK, rsm); 4423 #ifdef BBR_INVARIANTS 4424 if ((rsm->r_end - rsm->r_start) == 0) 4425 panic("tp:%p bbr:%p rsm:%p length is 0?", tp, bbr, rsm); 4426 #endif 4427 return (rsm); 4428 } 4429 return (NULL); 4430 } 4431 4432 /* 4433 * RACK Timer, here we simply do logging and house keeping. 4434 * the normal bbr_output_wtime() function will call the 4435 * appropriate thing to check if we need to do a RACK retransmit. 4436 * We return 1, saying don't proceed with bbr_output_wtime only 4437 * when all timers have been stopped (destroyed PCB?). 4438 */ 4439 static int 4440 bbr_timeout_rack(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts) 4441 { 4442 /* 4443 * This timer simply provides an internal trigger to send out data. 4444 * The check_recovery_mode call will see if there are needed 4445 * retransmissions, if so we will enter fast-recovery. The output 4446 * call may or may not do the same thing depending on sysctl 4447 * settings. 4448 */ 4449 uint32_t lost; 4450 4451 if (bbr->rc_all_timers_stopped) { 4452 return (1); 4453 } 4454 if (TSTMP_LT(cts, bbr->r_ctl.rc_timer_exp)) { 4455 /* Its not time yet */ 4456 return (0); 4457 } 4458 BBR_STAT_INC(bbr_to_tot); 4459 lost = bbr->r_ctl.rc_lost; 4460 if (bbr->r_state && (bbr->r_state != tp->t_state)) 4461 bbr_set_state(tp, bbr, 0); 4462 bbr_log_to_event(bbr, cts, BBR_TO_FRM_RACK); 4463 if (bbr->r_ctl.rc_resend == NULL) { 4464 /* Lets do the check here */ 4465 bbr->r_ctl.rc_resend = bbr_check_recovery_mode(tp, bbr, cts); 4466 } 4467 if (bbr_policer_call_from_rack_to) 4468 bbr_lt_bw_sampling(bbr, cts, (bbr->r_ctl.rc_lost > lost)); 4469 bbr->r_ctl.rc_hpts_flags &= ~PACE_TMR_RACK; 4470 return (0); 4471 } 4472 4473 static __inline void 4474 bbr_clone_rsm(struct tcp_bbr *bbr, struct bbr_sendmap *nrsm, struct bbr_sendmap *rsm, uint32_t start) 4475 { 4476 int idx; 4477 4478 nrsm->r_start = start; 4479 nrsm->r_end = rsm->r_end; 4480 nrsm->r_rtr_cnt = rsm->r_rtr_cnt; 4481 nrsm->r_flags = rsm->r_flags; 4482 /* We don't transfer forward the SYN flag */ 4483 nrsm->r_flags &= ~BBR_HAS_SYN; 4484 /* We move forward the FIN flag, not that this should happen */ 4485 rsm->r_flags &= ~BBR_HAS_FIN; 4486 nrsm->r_dupack = rsm->r_dupack; 4487 nrsm->r_rtr_bytes = 0; 4488 nrsm->r_is_gain = rsm->r_is_gain; 4489 nrsm->r_is_drain = rsm->r_is_drain; 4490 nrsm->r_delivered = rsm->r_delivered; 4491 nrsm->r_ts_valid = rsm->r_ts_valid; 4492 nrsm->r_del_ack_ts = rsm->r_del_ack_ts; 4493 nrsm->r_del_time = rsm->r_del_time; 4494 nrsm->r_app_limited = rsm->r_app_limited; 4495 nrsm->r_first_sent_time = rsm->r_first_sent_time; 4496 nrsm->r_flight_at_send = rsm->r_flight_at_send; 4497 /* We split a piece the lower section looses any just_ret flag. */ 4498 nrsm->r_bbr_state = rsm->r_bbr_state; 4499 for (idx = 0; idx < nrsm->r_rtr_cnt; idx++) { 4500 nrsm->r_tim_lastsent[idx] = rsm->r_tim_lastsent[idx]; 4501 } 4502 rsm->r_end = nrsm->r_start; 4503 idx = min((bbr->rc_tp->t_maxseg - bbr->rc_last_options), bbr->r_ctl.rc_pace_max_segs); 4504 idx /= 8; 4505 /* Check if we got too small */ 4506 if ((rsm->r_is_smallmap == 0) && 4507 ((rsm->r_end - rsm->r_start) <= idx)) { 4508 bbr->r_ctl.rc_num_small_maps_alloced++; 4509 rsm->r_is_smallmap = 1; 4510 } 4511 /* Check the new one as well */ 4512 if ((nrsm->r_end - nrsm->r_start) <= idx) { 4513 bbr->r_ctl.rc_num_small_maps_alloced++; 4514 nrsm->r_is_smallmap = 1; 4515 } 4516 } 4517 4518 static int 4519 bbr_sack_mergable(struct bbr_sendmap *at, 4520 uint32_t start, uint32_t end) 4521 { 4522 /* 4523 * Given a sack block defined by 4524 * start and end, and a current postion 4525 * at. Return 1 if either side of at 4526 * would show that the block is mergable 4527 * to that side. A block to be mergable 4528 * must have overlap with the start/end 4529 * and be in the SACK'd state. 4530 */ 4531 struct bbr_sendmap *l_rsm; 4532 struct bbr_sendmap *r_rsm; 4533 4534 /* first get the either side blocks */ 4535 l_rsm = TAILQ_PREV(at, bbr_head, r_next); 4536 r_rsm = TAILQ_NEXT(at, r_next); 4537 if (l_rsm && (l_rsm->r_flags & BBR_ACKED)) { 4538 /* Potentially mergeable */ 4539 if ((l_rsm->r_end == start) || 4540 (SEQ_LT(start, l_rsm->r_end) && 4541 SEQ_GT(end, l_rsm->r_end))) { 4542 /* 4543 * map blk |------| 4544 * sack blk |------| 4545 * <or> 4546 * map blk |------| 4547 * sack blk |------| 4548 */ 4549 return (1); 4550 } 4551 } 4552 if (r_rsm && (r_rsm->r_flags & BBR_ACKED)) { 4553 /* Potentially mergeable */ 4554 if ((r_rsm->r_start == end) || 4555 (SEQ_LT(start, r_rsm->r_start) && 4556 SEQ_GT(end, r_rsm->r_start))) { 4557 /* 4558 * map blk |---------| 4559 * sack blk |----| 4560 * <or> 4561 * map blk |---------| 4562 * sack blk |-------| 4563 */ 4564 return (1); 4565 } 4566 } 4567 return (0); 4568 } 4569 4570 static struct bbr_sendmap * 4571 bbr_merge_rsm(struct tcp_bbr *bbr, 4572 struct bbr_sendmap *l_rsm, 4573 struct bbr_sendmap *r_rsm) 4574 { 4575 /* 4576 * We are merging two ack'd RSM's, 4577 * the l_rsm is on the left (lower seq 4578 * values) and the r_rsm is on the right 4579 * (higher seq value). The simplest way 4580 * to merge these is to move the right 4581 * one into the left. I don't think there 4582 * is any reason we need to try to find 4583 * the oldest (or last oldest retransmitted). 4584 */ 4585 l_rsm->r_end = r_rsm->r_end; 4586 if (l_rsm->r_dupack < r_rsm->r_dupack) 4587 l_rsm->r_dupack = r_rsm->r_dupack; 4588 if (r_rsm->r_rtr_bytes) 4589 l_rsm->r_rtr_bytes += r_rsm->r_rtr_bytes; 4590 if (r_rsm->r_in_tmap) { 4591 /* This really should not happen */ 4592 TAILQ_REMOVE(&bbr->r_ctl.rc_tmap, r_rsm, r_tnext); 4593 } 4594 if (r_rsm->r_app_limited) 4595 l_rsm->r_app_limited = r_rsm->r_app_limited; 4596 /* Now the flags */ 4597 if (r_rsm->r_flags & BBR_HAS_FIN) 4598 l_rsm->r_flags |= BBR_HAS_FIN; 4599 if (r_rsm->r_flags & BBR_TLP) 4600 l_rsm->r_flags |= BBR_TLP; 4601 if (r_rsm->r_flags & BBR_RWND_COLLAPSED) 4602 l_rsm->r_flags |= BBR_RWND_COLLAPSED; 4603 if (r_rsm->r_flags & BBR_MARKED_LOST) { 4604 /* This really should not happen */ 4605 bbr->r_ctl.rc_lost_bytes -= r_rsm->r_end - r_rsm->r_start; 4606 } 4607 TAILQ_REMOVE(&bbr->r_ctl.rc_map, r_rsm, r_next); 4608 if ((r_rsm->r_limit_type == 0) && (l_rsm->r_limit_type != 0)) { 4609 /* Transfer the split limit to the map we free */ 4610 r_rsm->r_limit_type = l_rsm->r_limit_type; 4611 l_rsm->r_limit_type = 0; 4612 } 4613 bbr_free(bbr, r_rsm); 4614 return(l_rsm); 4615 } 4616 4617 /* 4618 * TLP Timer, here we simply setup what segment we want to 4619 * have the TLP expire on, the normal bbr_output_wtime() will then 4620 * send it out. 4621 * 4622 * We return 1, saying don't proceed with bbr_output_wtime only 4623 * when all timers have been stopped (destroyed PCB?). 4624 */ 4625 static int 4626 bbr_timeout_tlp(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts) 4627 { 4628 /* 4629 * Tail Loss Probe. 4630 */ 4631 struct bbr_sendmap *rsm = NULL; 4632 struct socket *so; 4633 uint32_t amm; 4634 uint32_t out, avail; 4635 uint32_t maxseg; 4636 int collapsed_win = 0; 4637 4638 if (bbr->rc_all_timers_stopped) { 4639 return (1); 4640 } 4641 if (TSTMP_LT(cts, bbr->r_ctl.rc_timer_exp)) { 4642 /* Its not time yet */ 4643 return (0); 4644 } 4645 if (bbr_progress_timeout_check(bbr)) { 4646 tcp_set_inp_to_drop(bbr->rc_inp, ETIMEDOUT); 4647 return (1); 4648 } 4649 /* Did we somehow get into persists? */ 4650 if (bbr->rc_in_persist) { 4651 return (0); 4652 } 4653 if (bbr->r_state && (bbr->r_state != tp->t_state)) 4654 bbr_set_state(tp, bbr, 0); 4655 BBR_STAT_INC(bbr_tlp_tot); 4656 maxseg = tp->t_maxseg - bbr->rc_last_options; 4657 #ifdef KERN_TLS 4658 if (bbr->rc_inp->inp_socket->so_snd.sb_flags & SB_TLS_IFNET) { 4659 /* 4660 * For hardware TLS we do *not* want to send 4661 * new data. 4662 */ 4663 goto need_retran; 4664 } 4665 #endif 4666 /* 4667 * A TLP timer has expired. We have been idle for 2 rtts. So we now 4668 * need to figure out how to force a full MSS segment out. 4669 */ 4670 so = tp->t_inpcb->inp_socket; 4671 avail = sbavail(&so->so_snd); 4672 out = ctf_outstanding(tp); 4673 if (out > tp->snd_wnd) { 4674 /* special case, we need a retransmission */ 4675 collapsed_win = 1; 4676 goto need_retran; 4677 } 4678 if (avail > out) { 4679 /* New data is available */ 4680 amm = avail - out; 4681 if (amm > maxseg) { 4682 amm = maxseg; 4683 } else if ((amm < maxseg) && ((tp->t_flags & TF_NODELAY) == 0)) { 4684 /* not enough to fill a MTU and no-delay is off */ 4685 goto need_retran; 4686 } 4687 /* Set the send-new override */ 4688 if ((out + amm) <= tp->snd_wnd) { 4689 bbr->rc_tlp_new_data = 1; 4690 } else { 4691 goto need_retran; 4692 } 4693 bbr->r_ctl.rc_tlp_seg_send_cnt = 0; 4694 bbr->r_ctl.rc_last_tlp_seq = tp->snd_max; 4695 bbr->r_ctl.rc_tlp_send = NULL; 4696 /* cap any slots */ 4697 BBR_STAT_INC(bbr_tlp_newdata); 4698 goto send; 4699 } 4700 need_retran: 4701 /* 4702 * Ok we need to arrange the last un-acked segment to be re-sent, or 4703 * optionally the first un-acked segment. 4704 */ 4705 if (collapsed_win == 0) { 4706 rsm = TAILQ_LAST_FAST(&bbr->r_ctl.rc_map, bbr_sendmap, r_next); 4707 if (rsm && (BBR_ACKED | BBR_HAS_FIN)) { 4708 rsm = bbr_find_high_nonack(bbr, rsm); 4709 } 4710 if (rsm == NULL) { 4711 goto restore; 4712 } 4713 } else { 4714 /* 4715 * We must find the last segment 4716 * that was acceptable by the client. 4717 */ 4718 TAILQ_FOREACH_REVERSE(rsm, &bbr->r_ctl.rc_map, bbr_head, r_next) { 4719 if ((rsm->r_flags & BBR_RWND_COLLAPSED) == 0) { 4720 /* Found one */ 4721 break; 4722 } 4723 } 4724 if (rsm == NULL) { 4725 /* None? if so send the first */ 4726 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map); 4727 if (rsm == NULL) 4728 goto restore; 4729 } 4730 } 4731 if ((rsm->r_end - rsm->r_start) > maxseg) { 4732 /* 4733 * We need to split this the last segment in two. 4734 */ 4735 struct bbr_sendmap *nrsm; 4736 4737 nrsm = bbr_alloc_full_limit(bbr); 4738 if (nrsm == NULL) { 4739 /* 4740 * We can't get memory to split, we can either just 4741 * not split it. Or retransmit the whole piece, lets 4742 * do the large send (BTLP :-) ). 4743 */ 4744 goto go_for_it; 4745 } 4746 bbr_clone_rsm(bbr, nrsm, rsm, (rsm->r_end - maxseg)); 4747 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_map, rsm, nrsm, r_next); 4748 if (rsm->r_in_tmap) { 4749 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, rsm, nrsm, r_tnext); 4750 nrsm->r_in_tmap = 1; 4751 } 4752 rsm->r_flags &= (~BBR_HAS_FIN); 4753 rsm = nrsm; 4754 } 4755 go_for_it: 4756 bbr->r_ctl.rc_tlp_send = rsm; 4757 bbr->rc_tlp_rtx_out = 1; 4758 if (rsm->r_start == bbr->r_ctl.rc_last_tlp_seq) { 4759 bbr->r_ctl.rc_tlp_seg_send_cnt++; 4760 tp->t_rxtshift++; 4761 } else { 4762 bbr->r_ctl.rc_last_tlp_seq = rsm->r_start; 4763 bbr->r_ctl.rc_tlp_seg_send_cnt = 1; 4764 } 4765 send: 4766 if (bbr->r_ctl.rc_tlp_seg_send_cnt > bbr_tlp_max_resend) { 4767 /* 4768 * Can't [re]/transmit a segment we have retranmitted the 4769 * max times. We need the retransmit timer to take over. 4770 */ 4771 restore: 4772 bbr->rc_tlp_new_data = 0; 4773 bbr->r_ctl.rc_tlp_send = NULL; 4774 if (rsm) 4775 rsm->r_flags &= ~BBR_TLP; 4776 BBR_STAT_INC(bbr_tlp_retran_fail); 4777 return (0); 4778 } else if (rsm) { 4779 rsm->r_flags |= BBR_TLP; 4780 } 4781 if (rsm && (rsm->r_start == bbr->r_ctl.rc_last_tlp_seq) && 4782 (bbr->r_ctl.rc_tlp_seg_send_cnt > bbr_tlp_max_resend)) { 4783 /* 4784 * We have retransmitted to many times for TLP. Switch to 4785 * the regular RTO timer 4786 */ 4787 goto restore; 4788 } 4789 bbr_log_to_event(bbr, cts, BBR_TO_FRM_TLP); 4790 bbr->r_ctl.rc_hpts_flags &= ~PACE_TMR_TLP; 4791 return (0); 4792 } 4793 4794 /* 4795 * Delayed ack Timer, here we simply need to setup the 4796 * ACK_NOW flag and remove the DELACK flag. From there 4797 * the output routine will send the ack out. 4798 * 4799 * We only return 1, saying don't proceed, if all timers 4800 * are stopped (destroyed PCB?). 4801 */ 4802 static int 4803 bbr_timeout_delack(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts) 4804 { 4805 if (bbr->rc_all_timers_stopped) { 4806 return (1); 4807 } 4808 bbr_log_to_event(bbr, cts, BBR_TO_FRM_DELACK); 4809 tp->t_flags &= ~TF_DELACK; 4810 tp->t_flags |= TF_ACKNOW; 4811 TCPSTAT_INC(tcps_delack); 4812 bbr->r_ctl.rc_hpts_flags &= ~PACE_TMR_DELACK; 4813 return (0); 4814 } 4815 4816 /* 4817 * Persists timer, here we simply need to setup the 4818 * FORCE-DATA flag the output routine will send 4819 * the one byte send. 4820 * 4821 * We only return 1, saying don't proceed, if all timers 4822 * are stopped (destroyed PCB?). 4823 */ 4824 static int 4825 bbr_timeout_persist(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts) 4826 { 4827 struct tcptemp *t_template; 4828 int32_t retval = 1; 4829 4830 if (bbr->rc_all_timers_stopped) { 4831 return (1); 4832 } 4833 if (bbr->rc_in_persist == 0) 4834 return (0); 4835 KASSERT(tp->t_inpcb != NULL, 4836 ("%s: tp %p tp->t_inpcb == NULL", __func__, tp)); 4837 /* 4838 * Persistence timer into zero window. Force a byte to be output, if 4839 * possible. 4840 */ 4841 bbr_log_to_event(bbr, cts, BBR_TO_FRM_PERSIST); 4842 bbr->r_ctl.rc_hpts_flags &= ~PACE_TMR_PERSIT; 4843 TCPSTAT_INC(tcps_persisttimeo); 4844 /* 4845 * Have we exceeded the user specified progress time? 4846 */ 4847 if (bbr_progress_timeout_check(bbr)) { 4848 tcp_set_inp_to_drop(bbr->rc_inp, ETIMEDOUT); 4849 goto out; 4850 } 4851 /* 4852 * Hack: if the peer is dead/unreachable, we do not time out if the 4853 * window is closed. After a full backoff, drop the connection if 4854 * the idle time (no responses to probes) reaches the maximum 4855 * backoff that we would use if retransmitting. 4856 */ 4857 if (tp->t_rxtshift == TCP_MAXRXTSHIFT && 4858 (ticks - tp->t_rcvtime >= tcp_maxpersistidle || 4859 ticks - tp->t_rcvtime >= TCP_REXMTVAL(tp) * tcp_totbackoff)) { 4860 TCPSTAT_INC(tcps_persistdrop); 4861 tcp_set_inp_to_drop(bbr->rc_inp, ETIMEDOUT); 4862 goto out; 4863 } 4864 if ((sbavail(&bbr->rc_inp->inp_socket->so_snd) == 0) && 4865 tp->snd_una == tp->snd_max) { 4866 bbr_exit_persist(tp, bbr, cts, __LINE__); 4867 retval = 0; 4868 goto out; 4869 } 4870 /* 4871 * If the user has closed the socket then drop a persisting 4872 * connection after a much reduced timeout. 4873 */ 4874 if (tp->t_state > TCPS_CLOSE_WAIT && 4875 (ticks - tp->t_rcvtime) >= TCPTV_PERSMAX) { 4876 TCPSTAT_INC(tcps_persistdrop); 4877 tcp_set_inp_to_drop(bbr->rc_inp, ETIMEDOUT); 4878 goto out; 4879 } 4880 t_template = tcpip_maketemplate(bbr->rc_inp); 4881 if (t_template) { 4882 tcp_respond(tp, t_template->tt_ipgen, 4883 &t_template->tt_t, (struct mbuf *)NULL, 4884 tp->rcv_nxt, tp->snd_una - 1, 0); 4885 /* This sends an ack */ 4886 if (tp->t_flags & TF_DELACK) 4887 tp->t_flags &= ~TF_DELACK; 4888 free(t_template, M_TEMP); 4889 } 4890 if (tp->t_rxtshift < TCP_MAXRXTSHIFT) 4891 tp->t_rxtshift++; 4892 bbr_start_hpts_timer(bbr, tp, cts, 3, 0, 0); 4893 out: 4894 return (retval); 4895 } 4896 4897 /* 4898 * If a keepalive goes off, we had no other timers 4899 * happening. We always return 1 here since this 4900 * routine either drops the connection or sends 4901 * out a segment with respond. 4902 */ 4903 static int 4904 bbr_timeout_keepalive(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts) 4905 { 4906 struct tcptemp *t_template; 4907 struct inpcb *inp; 4908 4909 if (bbr->rc_all_timers_stopped) { 4910 return (1); 4911 } 4912 bbr->r_ctl.rc_hpts_flags &= ~PACE_TMR_KEEP; 4913 inp = tp->t_inpcb; 4914 bbr_log_to_event(bbr, cts, BBR_TO_FRM_KEEP); 4915 /* 4916 * Keep-alive timer went off; send something or drop connection if 4917 * idle for too long. 4918 */ 4919 TCPSTAT_INC(tcps_keeptimeo); 4920 if (tp->t_state < TCPS_ESTABLISHED) 4921 goto dropit; 4922 if ((tcp_always_keepalive || inp->inp_socket->so_options & SO_KEEPALIVE) && 4923 tp->t_state <= TCPS_CLOSING) { 4924 if (ticks - tp->t_rcvtime >= TP_KEEPIDLE(tp) + TP_MAXIDLE(tp)) 4925 goto dropit; 4926 /* 4927 * Send a packet designed to force a response if the peer is 4928 * up and reachable: either an ACK if the connection is 4929 * still alive, or an RST if the peer has closed the 4930 * connection due to timeout or reboot. Using sequence 4931 * number tp->snd_una-1 causes the transmitted zero-length 4932 * segment to lie outside the receive window; by the 4933 * protocol spec, this requires the correspondent TCP to 4934 * respond. 4935 */ 4936 TCPSTAT_INC(tcps_keepprobe); 4937 t_template = tcpip_maketemplate(inp); 4938 if (t_template) { 4939 tcp_respond(tp, t_template->tt_ipgen, 4940 &t_template->tt_t, (struct mbuf *)NULL, 4941 tp->rcv_nxt, tp->snd_una - 1, 0); 4942 free(t_template, M_TEMP); 4943 } 4944 } 4945 bbr_start_hpts_timer(bbr, tp, cts, 4, 0, 0); 4946 return (1); 4947 dropit: 4948 TCPSTAT_INC(tcps_keepdrops); 4949 tcp_set_inp_to_drop(bbr->rc_inp, ETIMEDOUT); 4950 return (1); 4951 } 4952 4953 /* 4954 * Retransmit helper function, clear up all the ack 4955 * flags and take care of important book keeping. 4956 */ 4957 static void 4958 bbr_remxt_tmr(struct tcpcb *tp) 4959 { 4960 /* 4961 * The retransmit timer went off, all sack'd blocks must be 4962 * un-acked. 4963 */ 4964 struct bbr_sendmap *rsm, *trsm = NULL; 4965 struct tcp_bbr *bbr; 4966 uint32_t cts, lost; 4967 4968 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 4969 cts = tcp_get_usecs(&bbr->rc_tv); 4970 lost = bbr->r_ctl.rc_lost; 4971 if (bbr->r_state && (bbr->r_state != tp->t_state)) 4972 bbr_set_state(tp, bbr, 0); 4973 4974 TAILQ_FOREACH(rsm, &bbr->r_ctl.rc_map, r_next) { 4975 if (rsm->r_flags & BBR_ACKED) { 4976 uint32_t old_flags; 4977 4978 rsm->r_dupack = 0; 4979 if (rsm->r_in_tmap == 0) { 4980 /* We must re-add it back to the tlist */ 4981 if (trsm == NULL) { 4982 TAILQ_INSERT_HEAD(&bbr->r_ctl.rc_tmap, rsm, r_tnext); 4983 } else { 4984 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, trsm, rsm, r_tnext); 4985 } 4986 rsm->r_in_tmap = 1; 4987 } 4988 old_flags = rsm->r_flags; 4989 rsm->r_flags |= BBR_RXT_CLEARED; 4990 rsm->r_flags &= ~(BBR_ACKED | BBR_SACK_PASSED | BBR_WAS_SACKPASS); 4991 bbr_log_type_rsmclear(bbr, cts, rsm, old_flags, __LINE__); 4992 } else { 4993 if ((rsm->r_flags & BBR_MARKED_LOST) == 0) { 4994 bbr->r_ctl.rc_lost += rsm->r_end - rsm->r_start; 4995 bbr->r_ctl.rc_lost_bytes += rsm->r_end - rsm->r_start; 4996 } 4997 if (bbr_marks_rxt_sack_passed) { 4998 /* 4999 * With this option, we will rack out 5000 * in 1ms increments the rest of the packets. 5001 */ 5002 rsm->r_flags |= BBR_SACK_PASSED | BBR_MARKED_LOST; 5003 rsm->r_flags &= ~BBR_WAS_SACKPASS; 5004 } else { 5005 /* 5006 * With this option we only mark them lost 5007 * and remove all sack'd markings. We will run 5008 * another RXT or a TLP. This will cause 5009 * us to eventually send more based on what 5010 * ack's come in. 5011 */ 5012 rsm->r_flags |= BBR_MARKED_LOST; 5013 rsm->r_flags &= ~BBR_WAS_SACKPASS; 5014 rsm->r_flags &= ~BBR_SACK_PASSED; 5015 } 5016 } 5017 trsm = rsm; 5018 } 5019 bbr->r_ctl.rc_resend = TAILQ_FIRST(&bbr->r_ctl.rc_map); 5020 /* Clear the count (we just un-acked them) */ 5021 bbr_log_to_event(bbr, cts, BBR_TO_FRM_TMR); 5022 bbr->rc_tlp_new_data = 0; 5023 bbr->r_ctl.rc_tlp_seg_send_cnt = 0; 5024 /* zap the behindness on a rxt */ 5025 bbr->r_ctl.rc_hptsi_agg_delay = 0; 5026 bbr->r_agg_early_set = 0; 5027 bbr->r_ctl.rc_agg_early = 0; 5028 bbr->rc_tlp_rtx_out = 0; 5029 bbr->r_ctl.rc_sacked = 0; 5030 bbr->r_ctl.rc_sacklast = NULL; 5031 bbr->r_timer_override = 1; 5032 bbr_lt_bw_sampling(bbr, cts, (bbr->r_ctl.rc_lost > lost)); 5033 } 5034 5035 /* 5036 * Re-transmit timeout! If we drop the PCB we will return 1, otherwise 5037 * we will setup to retransmit the lowest seq number outstanding. 5038 */ 5039 static int 5040 bbr_timeout_rxt(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts) 5041 { 5042 int32_t rexmt; 5043 int32_t retval = 0; 5044 5045 bbr->r_ctl.rc_hpts_flags &= ~PACE_TMR_RXT; 5046 if (bbr->rc_all_timers_stopped) { 5047 return (1); 5048 } 5049 if (TCPS_HAVEESTABLISHED(tp->t_state) && 5050 (tp->snd_una == tp->snd_max)) { 5051 /* Nothing outstanding .. nothing to do */ 5052 return (0); 5053 } 5054 /* 5055 * Retransmission timer went off. Message has not been acked within 5056 * retransmit interval. Back off to a longer retransmit interval 5057 * and retransmit one segment. 5058 */ 5059 if (bbr_progress_timeout_check(bbr)) { 5060 retval = 1; 5061 tcp_set_inp_to_drop(bbr->rc_inp, ETIMEDOUT); 5062 goto out; 5063 } 5064 bbr_remxt_tmr(tp); 5065 if ((bbr->r_ctl.rc_resend == NULL) || 5066 ((bbr->r_ctl.rc_resend->r_flags & BBR_RWND_COLLAPSED) == 0)) { 5067 /* 5068 * If the rwnd collapsed on 5069 * the one we are retransmitting 5070 * it does not count against the 5071 * rxt count. 5072 */ 5073 tp->t_rxtshift++; 5074 } 5075 if (tp->t_rxtshift > TCP_MAXRXTSHIFT) { 5076 tp->t_rxtshift = TCP_MAXRXTSHIFT; 5077 TCPSTAT_INC(tcps_timeoutdrop); 5078 retval = 1; 5079 tcp_set_inp_to_drop(bbr->rc_inp, 5080 (tp->t_softerror ? (uint16_t) tp->t_softerror : ETIMEDOUT)); 5081 goto out; 5082 } 5083 if (tp->t_state == TCPS_SYN_SENT) { 5084 /* 5085 * If the SYN was retransmitted, indicate CWND to be limited 5086 * to 1 segment in cc_conn_init(). 5087 */ 5088 tp->snd_cwnd = 1; 5089 } else if (tp->t_rxtshift == 1) { 5090 /* 5091 * first retransmit; record ssthresh and cwnd so they can be 5092 * recovered if this turns out to be a "bad" retransmit. A 5093 * retransmit is considered "bad" if an ACK for this segment 5094 * is received within RTT/2 interval; the assumption here is 5095 * that the ACK was already in flight. See "On Estimating 5096 * End-to-End Network Path Properties" by Allman and Paxson 5097 * for more details. 5098 */ 5099 tp->snd_cwnd = tp->t_maxseg - bbr->rc_last_options; 5100 if (!IN_RECOVERY(tp->t_flags)) { 5101 tp->snd_cwnd_prev = tp->snd_cwnd; 5102 tp->snd_ssthresh_prev = tp->snd_ssthresh; 5103 tp->snd_recover_prev = tp->snd_recover; 5104 tp->t_badrxtwin = ticks + (tp->t_srtt >> (TCP_RTT_SHIFT + 1)); 5105 tp->t_flags |= TF_PREVVALID; 5106 } else { 5107 tp->t_flags &= ~TF_PREVVALID; 5108 } 5109 tp->snd_cwnd = tp->t_maxseg - bbr->rc_last_options; 5110 } else { 5111 tp->snd_cwnd = tp->t_maxseg - bbr->rc_last_options; 5112 tp->t_flags &= ~TF_PREVVALID; 5113 } 5114 TCPSTAT_INC(tcps_rexmttimeo); 5115 if ((tp->t_state == TCPS_SYN_SENT) || 5116 (tp->t_state == TCPS_SYN_RECEIVED)) 5117 rexmt = USEC_2_TICKS(BBR_INITIAL_RTO) * tcp_backoff[tp->t_rxtshift]; 5118 else 5119 rexmt = TCP_REXMTVAL(tp) * tcp_backoff[tp->t_rxtshift]; 5120 TCPT_RANGESET(tp->t_rxtcur, rexmt, 5121 MSEC_2_TICKS(bbr->r_ctl.rc_min_rto_ms), 5122 MSEC_2_TICKS(((uint32_t)bbr->rc_max_rto_sec) * 1000)); 5123 /* 5124 * We enter the path for PLMTUD if connection is established or, if 5125 * connection is FIN_WAIT_1 status, reason for the last is that if 5126 * amount of data we send is very small, we could send it in couple 5127 * of packets and process straight to FIN. In that case we won't 5128 * catch ESTABLISHED state. 5129 */ 5130 if (V_tcp_pmtud_blackhole_detect && (((tp->t_state == TCPS_ESTABLISHED)) 5131 || (tp->t_state == TCPS_FIN_WAIT_1))) { 5132 #ifdef INET6 5133 int32_t isipv6; 5134 #endif 5135 5136 /* 5137 * Idea here is that at each stage of mtu probe (usually, 5138 * 1448 -> 1188 -> 524) should be given 2 chances to recover 5139 * before further clamping down. 'tp->t_rxtshift % 2 == 0' 5140 * should take care of that. 5141 */ 5142 if (((tp->t_flags2 & (TF2_PLPMTU_PMTUD | TF2_PLPMTU_MAXSEGSNT)) == 5143 (TF2_PLPMTU_PMTUD | TF2_PLPMTU_MAXSEGSNT)) && 5144 (tp->t_rxtshift >= 2 && tp->t_rxtshift < 6 && 5145 tp->t_rxtshift % 2 == 0)) { 5146 /* 5147 * Enter Path MTU Black-hole Detection mechanism: - 5148 * Disable Path MTU Discovery (IP "DF" bit). - 5149 * Reduce MTU to lower value than what we negotiated 5150 * with peer. 5151 */ 5152 if ((tp->t_flags2 & TF2_PLPMTU_BLACKHOLE) == 0) { 5153 /* 5154 * Record that we may have found a black 5155 * hole. 5156 */ 5157 tp->t_flags2 |= TF2_PLPMTU_BLACKHOLE; 5158 /* Keep track of previous MSS. */ 5159 tp->t_pmtud_saved_maxseg = tp->t_maxseg; 5160 } 5161 /* 5162 * Reduce the MSS to blackhole value or to the 5163 * default in an attempt to retransmit. 5164 */ 5165 #ifdef INET6 5166 isipv6 = bbr->r_is_v6; 5167 if (isipv6 && 5168 tp->t_maxseg > V_tcp_v6pmtud_blackhole_mss) { 5169 /* Use the sysctl tuneable blackhole MSS. */ 5170 tp->t_maxseg = V_tcp_v6pmtud_blackhole_mss; 5171 TCPSTAT_INC(tcps_pmtud_blackhole_activated); 5172 } else if (isipv6) { 5173 /* Use the default MSS. */ 5174 tp->t_maxseg = V_tcp_v6mssdflt; 5175 /* 5176 * Disable Path MTU Discovery when we switch 5177 * to minmss. 5178 */ 5179 tp->t_flags2 &= ~TF2_PLPMTU_PMTUD; 5180 TCPSTAT_INC(tcps_pmtud_blackhole_activated_min_mss); 5181 } 5182 #endif 5183 #if defined(INET6) && defined(INET) 5184 else 5185 #endif 5186 #ifdef INET 5187 if (tp->t_maxseg > V_tcp_pmtud_blackhole_mss) { 5188 /* Use the sysctl tuneable blackhole MSS. */ 5189 tp->t_maxseg = V_tcp_pmtud_blackhole_mss; 5190 TCPSTAT_INC(tcps_pmtud_blackhole_activated); 5191 } else { 5192 /* Use the default MSS. */ 5193 tp->t_maxseg = V_tcp_mssdflt; 5194 /* 5195 * Disable Path MTU Discovery when we switch 5196 * to minmss. 5197 */ 5198 tp->t_flags2 &= ~TF2_PLPMTU_PMTUD; 5199 TCPSTAT_INC(tcps_pmtud_blackhole_activated_min_mss); 5200 } 5201 #endif 5202 } else { 5203 /* 5204 * If further retransmissions are still unsuccessful 5205 * with a lowered MTU, maybe this isn't a blackhole 5206 * and we restore the previous MSS and blackhole 5207 * detection flags. The limit '6' is determined by 5208 * giving each probe stage (1448, 1188, 524) 2 5209 * chances to recover. 5210 */ 5211 if ((tp->t_flags2 & TF2_PLPMTU_BLACKHOLE) && 5212 (tp->t_rxtshift >= 6)) { 5213 tp->t_flags2 |= TF2_PLPMTU_PMTUD; 5214 tp->t_flags2 &= ~TF2_PLPMTU_BLACKHOLE; 5215 tp->t_maxseg = tp->t_pmtud_saved_maxseg; 5216 TCPSTAT_INC(tcps_pmtud_blackhole_failed); 5217 } 5218 } 5219 } 5220 /* 5221 * Disable RFC1323 and SACK if we haven't got any response to our 5222 * third SYN to work-around some broken terminal servers (most of 5223 * which have hopefully been retired) that have bad VJ header 5224 * compression code which trashes TCP segments containing 5225 * unknown-to-them TCP options. 5226 */ 5227 if (tcp_rexmit_drop_options && (tp->t_state == TCPS_SYN_SENT) && 5228 (tp->t_rxtshift == 3)) 5229 tp->t_flags &= ~(TF_REQ_SCALE | TF_REQ_TSTMP | TF_SACK_PERMIT); 5230 /* 5231 * If we backed off this far, our srtt estimate is probably bogus. 5232 * Clobber it so we'll take the next rtt measurement as our srtt; 5233 * move the current srtt into rttvar to keep the current retransmit 5234 * times until then. 5235 */ 5236 if (tp->t_rxtshift > TCP_MAXRXTSHIFT / 4) { 5237 #ifdef INET6 5238 if (bbr->r_is_v6) 5239 in6_losing(tp->t_inpcb); 5240 else 5241 #endif 5242 in_losing(tp->t_inpcb); 5243 tp->t_rttvar += (tp->t_srtt >> TCP_RTT_SHIFT); 5244 tp->t_srtt = 0; 5245 } 5246 sack_filter_clear(&bbr->r_ctl.bbr_sf, tp->snd_una); 5247 tp->snd_recover = tp->snd_max; 5248 tp->t_flags |= TF_ACKNOW; 5249 tp->t_rtttime = 0; 5250 out: 5251 return (retval); 5252 } 5253 5254 static int 5255 bbr_process_timers(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts, uint8_t hpts_calling) 5256 { 5257 int32_t ret = 0; 5258 int32_t timers = (bbr->r_ctl.rc_hpts_flags & PACE_TMR_MASK); 5259 5260 if (timers == 0) { 5261 return (0); 5262 } 5263 if (tp->t_state == TCPS_LISTEN) { 5264 /* no timers on listen sockets */ 5265 if (bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) 5266 return (0); 5267 return (1); 5268 } 5269 if (TSTMP_LT(cts, bbr->r_ctl.rc_timer_exp)) { 5270 uint32_t left; 5271 5272 if (bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) { 5273 ret = -1; 5274 bbr_log_to_processing(bbr, cts, ret, 0, hpts_calling); 5275 return (0); 5276 } 5277 if (hpts_calling == 0) { 5278 ret = -2; 5279 bbr_log_to_processing(bbr, cts, ret, 0, hpts_calling); 5280 return (0); 5281 } 5282 /* 5283 * Ok our timer went off early and we are not paced false 5284 * alarm, go back to sleep. 5285 */ 5286 left = bbr->r_ctl.rc_timer_exp - cts; 5287 ret = -3; 5288 bbr_log_to_processing(bbr, cts, ret, left, hpts_calling); 5289 tcp_hpts_insert(tp->t_inpcb, HPTS_USEC_TO_SLOTS(left)); 5290 return (1); 5291 } 5292 bbr->rc_tmr_stopped = 0; 5293 bbr->r_ctl.rc_hpts_flags &= ~PACE_TMR_MASK; 5294 if (timers & PACE_TMR_DELACK) { 5295 ret = bbr_timeout_delack(tp, bbr, cts); 5296 } else if (timers & PACE_TMR_PERSIT) { 5297 ret = bbr_timeout_persist(tp, bbr, cts); 5298 } else if (timers & PACE_TMR_RACK) { 5299 bbr->r_ctl.rc_tlp_rxt_last_time = cts; 5300 ret = bbr_timeout_rack(tp, bbr, cts); 5301 } else if (timers & PACE_TMR_TLP) { 5302 bbr->r_ctl.rc_tlp_rxt_last_time = cts; 5303 ret = bbr_timeout_tlp(tp, bbr, cts); 5304 } else if (timers & PACE_TMR_RXT) { 5305 bbr->r_ctl.rc_tlp_rxt_last_time = cts; 5306 ret = bbr_timeout_rxt(tp, bbr, cts); 5307 } else if (timers & PACE_TMR_KEEP) { 5308 ret = bbr_timeout_keepalive(tp, bbr, cts); 5309 } 5310 bbr_log_to_processing(bbr, cts, ret, timers, hpts_calling); 5311 return (ret); 5312 } 5313 5314 static void 5315 bbr_timer_cancel(struct tcp_bbr *bbr, int32_t line, uint32_t cts) 5316 { 5317 if (bbr->r_ctl.rc_hpts_flags & PACE_TMR_MASK) { 5318 uint8_t hpts_removed = 0; 5319 5320 if (bbr->rc_inp->inp_in_hpts && 5321 (bbr->rc_timer_first == 1)) { 5322 /* 5323 * If we are canceling timer's when we have the 5324 * timer ahead of the output being paced. We also 5325 * must remove ourselves from the hpts. 5326 */ 5327 hpts_removed = 1; 5328 tcp_hpts_remove(bbr->rc_inp, HPTS_REMOVE_OUTPUT); 5329 if (bbr->r_ctl.rc_last_delay_val) { 5330 /* Update the last hptsi delay too */ 5331 uint32_t time_since_send; 5332 5333 if (TSTMP_GT(cts, bbr->rc_pacer_started)) 5334 time_since_send = cts - bbr->rc_pacer_started; 5335 else 5336 time_since_send = 0; 5337 if (bbr->r_ctl.rc_last_delay_val > time_since_send) { 5338 /* Cut down our slot time */ 5339 bbr->r_ctl.rc_last_delay_val -= time_since_send; 5340 } else { 5341 bbr->r_ctl.rc_last_delay_val = 0; 5342 } 5343 bbr->rc_pacer_started = cts; 5344 } 5345 } 5346 bbr->rc_timer_first = 0; 5347 bbr_log_to_cancel(bbr, line, cts, hpts_removed); 5348 bbr->rc_tmr_stopped = bbr->r_ctl.rc_hpts_flags & PACE_TMR_MASK; 5349 bbr->r_ctl.rc_hpts_flags &= ~(PACE_TMR_MASK); 5350 } 5351 } 5352 5353 static void 5354 bbr_timer_stop(struct tcpcb *tp, uint32_t timer_type) 5355 { 5356 struct tcp_bbr *bbr; 5357 5358 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 5359 bbr->rc_all_timers_stopped = 1; 5360 return; 5361 } 5362 5363 /* 5364 * stop all timers always returning 0. 5365 */ 5366 static int 5367 bbr_stopall(struct tcpcb *tp) 5368 { 5369 return (0); 5370 } 5371 5372 static void 5373 bbr_timer_activate(struct tcpcb *tp, uint32_t timer_type, uint32_t delta) 5374 { 5375 return; 5376 } 5377 5378 /* 5379 * return true if a bbr timer (rack or tlp) is active. 5380 */ 5381 static int 5382 bbr_timer_active(struct tcpcb *tp, uint32_t timer_type) 5383 { 5384 return (0); 5385 } 5386 5387 static uint32_t 5388 bbr_get_earliest_send_outstanding(struct tcp_bbr *bbr, struct bbr_sendmap *u_rsm, uint32_t cts) 5389 { 5390 struct bbr_sendmap *rsm; 5391 5392 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_tmap); 5393 if ((rsm == NULL) || (u_rsm == rsm)) 5394 return (cts); 5395 return(rsm->r_tim_lastsent[(rsm->r_rtr_cnt-1)]); 5396 } 5397 5398 static void 5399 bbr_update_rsm(struct tcpcb *tp, struct tcp_bbr *bbr, 5400 struct bbr_sendmap *rsm, uint32_t cts, uint32_t pacing_time) 5401 { 5402 int32_t idx; 5403 5404 rsm->r_rtr_cnt++; 5405 rsm->r_dupack = 0; 5406 if (rsm->r_rtr_cnt > BBR_NUM_OF_RETRANS) { 5407 rsm->r_rtr_cnt = BBR_NUM_OF_RETRANS; 5408 rsm->r_flags |= BBR_OVERMAX; 5409 } 5410 if (rsm->r_flags & BBR_RWND_COLLAPSED) { 5411 /* Take off the collapsed flag at rxt */ 5412 rsm->r_flags &= ~BBR_RWND_COLLAPSED; 5413 } 5414 if (rsm->r_flags & BBR_MARKED_LOST) { 5415 /* We have retransmitted, its no longer lost */ 5416 rsm->r_flags &= ~BBR_MARKED_LOST; 5417 bbr->r_ctl.rc_lost_bytes -= rsm->r_end - rsm->r_start; 5418 } 5419 if (rsm->r_flags & BBR_RXT_CLEARED) { 5420 /* 5421 * We hit a RXT timer on it and 5422 * we cleared the "acked" flag. 5423 * We now have it going back into 5424 * flight, we can remove the cleared 5425 * flag and possibly do accounting on 5426 * this piece. 5427 */ 5428 rsm->r_flags &= ~BBR_RXT_CLEARED; 5429 } 5430 if ((rsm->r_rtr_cnt > 1) && ((rsm->r_flags & BBR_TLP) == 0)) { 5431 bbr->r_ctl.rc_holes_rxt += (rsm->r_end - rsm->r_start); 5432 rsm->r_rtr_bytes += (rsm->r_end - rsm->r_start); 5433 } 5434 idx = rsm->r_rtr_cnt - 1; 5435 rsm->r_tim_lastsent[idx] = cts; 5436 rsm->r_pacing_delay = pacing_time; 5437 rsm->r_delivered = bbr->r_ctl.rc_delivered; 5438 rsm->r_ts_valid = bbr->rc_ts_valid; 5439 if (bbr->rc_ts_valid) 5440 rsm->r_del_ack_ts = bbr->r_ctl.last_inbound_ts; 5441 if (bbr->r_ctl.r_app_limited_until) 5442 rsm->r_app_limited = 1; 5443 else 5444 rsm->r_app_limited = 0; 5445 if (bbr->rc_bbr_state == BBR_STATE_PROBE_BW) 5446 rsm->r_bbr_state = bbr_state_val(bbr); 5447 else 5448 rsm->r_bbr_state = 8; 5449 if (rsm->r_flags & BBR_ACKED) { 5450 /* Problably MTU discovery messing with us */ 5451 uint32_t old_flags; 5452 5453 old_flags = rsm->r_flags; 5454 rsm->r_flags &= ~BBR_ACKED; 5455 bbr_log_type_rsmclear(bbr, cts, rsm, old_flags, __LINE__); 5456 bbr->r_ctl.rc_sacked -= (rsm->r_end - rsm->r_start); 5457 if (bbr->r_ctl.rc_sacked == 0) 5458 bbr->r_ctl.rc_sacklast = NULL; 5459 } 5460 if (rsm->r_in_tmap) { 5461 TAILQ_REMOVE(&bbr->r_ctl.rc_tmap, rsm, r_tnext); 5462 } 5463 TAILQ_INSERT_TAIL(&bbr->r_ctl.rc_tmap, rsm, r_tnext); 5464 rsm->r_in_tmap = 1; 5465 if (rsm->r_flags & BBR_SACK_PASSED) { 5466 /* We have retransmitted due to the SACK pass */ 5467 rsm->r_flags &= ~BBR_SACK_PASSED; 5468 rsm->r_flags |= BBR_WAS_SACKPASS; 5469 } 5470 rsm->r_first_sent_time = bbr_get_earliest_send_outstanding(bbr, rsm, cts); 5471 rsm->r_flight_at_send = ctf_flight_size(bbr->rc_tp, 5472 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 5473 bbr->r_ctl.rc_next = TAILQ_NEXT(rsm, r_next); 5474 if (bbr->r_ctl.rc_bbr_hptsi_gain > BBR_UNIT) { 5475 rsm->r_is_gain = 1; 5476 rsm->r_is_drain = 0; 5477 } else if (bbr->r_ctl.rc_bbr_hptsi_gain < BBR_UNIT) { 5478 rsm->r_is_drain = 1; 5479 rsm->r_is_gain = 0; 5480 } else { 5481 rsm->r_is_drain = 0; 5482 rsm->r_is_gain = 0; 5483 } 5484 rsm->r_del_time = bbr->r_ctl.rc_del_time; /* TEMP GOOGLE CODE */ 5485 } 5486 5487 /* 5488 * Returns 0, or the sequence where we stopped 5489 * updating. We also update the lenp to be the amount 5490 * of data left. 5491 */ 5492 5493 static uint32_t 5494 bbr_update_entry(struct tcpcb *tp, struct tcp_bbr *bbr, 5495 struct bbr_sendmap *rsm, uint32_t cts, int32_t *lenp, uint32_t pacing_time) 5496 { 5497 /* 5498 * We (re-)transmitted starting at rsm->r_start for some length 5499 * (possibly less than r_end. 5500 */ 5501 struct bbr_sendmap *nrsm; 5502 uint32_t c_end; 5503 int32_t len; 5504 5505 len = *lenp; 5506 c_end = rsm->r_start + len; 5507 if (SEQ_GEQ(c_end, rsm->r_end)) { 5508 /* 5509 * We retransmitted the whole piece or more than the whole 5510 * slopping into the next rsm. 5511 */ 5512 bbr_update_rsm(tp, bbr, rsm, cts, pacing_time); 5513 if (c_end == rsm->r_end) { 5514 *lenp = 0; 5515 return (0); 5516 } else { 5517 int32_t act_len; 5518 5519 /* Hangs over the end return whats left */ 5520 act_len = rsm->r_end - rsm->r_start; 5521 *lenp = (len - act_len); 5522 return (rsm->r_end); 5523 } 5524 /* We don't get out of this block. */ 5525 } 5526 /* 5527 * Here we retransmitted less than the whole thing which means we 5528 * have to split this into what was transmitted and what was not. 5529 */ 5530 nrsm = bbr_alloc_full_limit(bbr); 5531 if (nrsm == NULL) { 5532 *lenp = 0; 5533 return (0); 5534 } 5535 /* 5536 * So here we are going to take the original rsm and make it what we 5537 * retransmitted. nrsm will be the tail portion we did not 5538 * retransmit. For example say the chunk was 1, 11 (10 bytes). And 5539 * we retransmitted 5 bytes i.e. 1, 5. The original piece shrinks to 5540 * 1, 6 and the new piece will be 6, 11. 5541 */ 5542 bbr_clone_rsm(bbr, nrsm, rsm, c_end); 5543 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_map, rsm, nrsm, r_next); 5544 nrsm->r_dupack = 0; 5545 if (rsm->r_in_tmap) { 5546 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, rsm, nrsm, r_tnext); 5547 nrsm->r_in_tmap = 1; 5548 } 5549 rsm->r_flags &= (~BBR_HAS_FIN); 5550 bbr_update_rsm(tp, bbr, rsm, cts, pacing_time); 5551 *lenp = 0; 5552 return (0); 5553 } 5554 5555 static uint64_t 5556 bbr_get_hardware_rate(struct tcp_bbr *bbr) 5557 { 5558 uint64_t bw; 5559 5560 bw = bbr_get_bw(bbr); 5561 bw *= (uint64_t)bbr_hptsi_gain[BBR_SUB_GAIN]; 5562 bw /= (uint64_t)BBR_UNIT; 5563 return(bw); 5564 } 5565 5566 static void 5567 bbr_setup_less_of_rate(struct tcp_bbr *bbr, uint32_t cts, 5568 uint64_t act_rate, uint64_t rate_wanted) 5569 { 5570 /* 5571 * We could not get a full gains worth 5572 * of rate. 5573 */ 5574 if (get_filter_value(&bbr->r_ctl.rc_delrate) >= act_rate) { 5575 /* we can't even get the real rate */ 5576 uint64_t red; 5577 5578 bbr->skip_gain = 1; 5579 bbr->gain_is_limited = 0; 5580 red = get_filter_value(&bbr->r_ctl.rc_delrate) - act_rate; 5581 if (red) 5582 filter_reduce_by(&bbr->r_ctl.rc_delrate, red, cts); 5583 } else { 5584 /* We can use a lower gain */ 5585 bbr->skip_gain = 0; 5586 bbr->gain_is_limited = 1; 5587 } 5588 } 5589 5590 static void 5591 bbr_update_hardware_pacing_rate(struct tcp_bbr *bbr, uint32_t cts) 5592 { 5593 const struct tcp_hwrate_limit_table *nrte; 5594 int error, rate = -1; 5595 5596 if (bbr->r_ctl.crte == NULL) 5597 return; 5598 if ((bbr->rc_inp->inp_route.ro_rt == NULL) || 5599 (bbr->rc_inp->inp_route.ro_rt->rt_ifp == NULL)) { 5600 /* Lost our routes? */ 5601 /* Clear the way for a re-attempt */ 5602 bbr->bbr_attempt_hdwr_pace = 0; 5603 lost_rate: 5604 bbr->gain_is_limited = 0; 5605 bbr->skip_gain = 0; 5606 bbr->bbr_hdrw_pacing = 0; 5607 counter_u64_add(bbr_flows_whdwr_pacing, -1); 5608 counter_u64_add(bbr_flows_nohdwr_pacing, 1); 5609 tcp_bbr_tso_size_check(bbr, cts); 5610 return; 5611 } 5612 rate = bbr_get_hardware_rate(bbr); 5613 nrte = tcp_chg_pacing_rate(bbr->r_ctl.crte, 5614 bbr->rc_tp, 5615 bbr->rc_inp->inp_route.ro_rt->rt_ifp, 5616 rate, 5617 (RS_PACING_GEQ|RS_PACING_SUB_OK), 5618 &error); 5619 if (nrte == NULL) { 5620 goto lost_rate; 5621 } 5622 if (nrte != bbr->r_ctl.crte) { 5623 bbr->r_ctl.crte = nrte; 5624 if (error == 0) { 5625 BBR_STAT_INC(bbr_hdwr_rl_mod_ok); 5626 if (bbr->r_ctl.crte->rate < rate) { 5627 /* We have a problem */ 5628 bbr_setup_less_of_rate(bbr, cts, 5629 bbr->r_ctl.crte->rate, rate); 5630 } else { 5631 /* We are good */ 5632 bbr->gain_is_limited = 0; 5633 bbr->skip_gain = 0; 5634 } 5635 } else { 5636 /* A failure should release the tag */ 5637 BBR_STAT_INC(bbr_hdwr_rl_mod_fail); 5638 bbr->gain_is_limited = 0; 5639 bbr->skip_gain = 0; 5640 bbr->bbr_hdrw_pacing = 0; 5641 } 5642 bbr_type_log_hdwr_pacing(bbr, 5643 bbr->r_ctl.crte->ptbl->rs_ifp, 5644 rate, 5645 ((bbr->r_ctl.crte == NULL) ? 0 : bbr->r_ctl.crte->rate), 5646 __LINE__, 5647 cts, 5648 error); 5649 } 5650 } 5651 5652 static void 5653 bbr_adjust_for_hw_pacing(struct tcp_bbr *bbr, uint32_t cts) 5654 { 5655 /* 5656 * If we have hardware pacing support 5657 * we need to factor that in for our 5658 * TSO size. 5659 */ 5660 const struct tcp_hwrate_limit_table *rlp; 5661 uint32_t cur_delay, seg_sz, maxseg, new_tso, delta, hdwr_delay; 5662 5663 if ((bbr->bbr_hdrw_pacing == 0) || 5664 (IN_RECOVERY(bbr->rc_tp->t_flags)) || 5665 (bbr->r_ctl.crte == NULL)) 5666 return; 5667 if (bbr->hw_pacing_set == 0) { 5668 /* Not yet by the hdwr pacing count delay */ 5669 return; 5670 } 5671 if (bbr_hdwr_pace_adjust == 0) { 5672 /* No adjustment */ 5673 return; 5674 } 5675 rlp = bbr->r_ctl.crte; 5676 if (bbr->rc_tp->t_maxseg > bbr->rc_last_options) 5677 maxseg = bbr->rc_tp->t_maxseg - bbr->rc_last_options; 5678 else 5679 maxseg = BBR_MIN_SEG - bbr->rc_last_options; 5680 /* 5681 * So lets first get the 5682 * time we will take between 5683 * TSO sized sends currently without 5684 * hardware help. 5685 */ 5686 cur_delay = bbr_get_pacing_delay(bbr, BBR_UNIT, 5687 bbr->r_ctl.rc_pace_max_segs, cts, 1); 5688 hdwr_delay = bbr->r_ctl.rc_pace_max_segs / maxseg; 5689 hdwr_delay *= rlp->time_between; 5690 if (cur_delay > hdwr_delay) 5691 delta = cur_delay - hdwr_delay; 5692 else 5693 delta = 0; 5694 bbr_log_type_tsosize(bbr, cts, delta, cur_delay, hdwr_delay, 5695 (bbr->r_ctl.rc_pace_max_segs / maxseg), 5696 1); 5697 if (delta && 5698 (delta < (max(rlp->time_between, 5699 bbr->r_ctl.bbr_hptsi_segments_delay_tar)))) { 5700 /* 5701 * Now lets divide by the pacing 5702 * time between each segment the 5703 * hardware sends rounding up and 5704 * derive a bytes from that. We multiply 5705 * that by bbr_hdwr_pace_adjust to get 5706 * more bang for our buck. 5707 * 5708 * The goal is to have the software pacer 5709 * waiting no more than an additional 5710 * pacing delay if we can (without the 5711 * compensation i.e. x bbr_hdwr_pace_adjust). 5712 */ 5713 seg_sz = max(((cur_delay + rlp->time_between)/rlp->time_between), 5714 (bbr->r_ctl.rc_pace_max_segs/maxseg)); 5715 seg_sz *= bbr_hdwr_pace_adjust; 5716 if (bbr_hdwr_pace_floor && 5717 (seg_sz < bbr->r_ctl.crte->ptbl->rs_min_seg)) { 5718 /* Currently hardware paces 5719 * out rs_min_seg segments at a time. 5720 * We need to make sure we always send at least 5721 * a full burst of bbr_hdwr_pace_floor down. 5722 */ 5723 seg_sz = bbr->r_ctl.crte->ptbl->rs_min_seg; 5724 } 5725 seg_sz *= maxseg; 5726 } else if (delta == 0) { 5727 /* 5728 * The highest pacing rate is 5729 * above our b/w gained. This means 5730 * we probably are going quite fast at 5731 * the hardware highest rate. Lets just multiply 5732 * the calculated TSO size by the 5733 * multiplier factor (its probably 5734 * 4 segments in the default config for 5735 * mlx). 5736 */ 5737 seg_sz = bbr->r_ctl.rc_pace_max_segs * bbr_hdwr_pace_adjust; 5738 if (bbr_hdwr_pace_floor && 5739 (seg_sz < bbr->r_ctl.crte->ptbl->rs_min_seg)) { 5740 /* Currently hardware paces 5741 * out rs_min_seg segments at a time. 5742 * We need to make sure we always send at least 5743 * a full burst of bbr_hdwr_pace_floor down. 5744 */ 5745 seg_sz = bbr->r_ctl.crte->ptbl->rs_min_seg; 5746 } 5747 } else { 5748 /* 5749 * The pacing time difference is so 5750 * big that the hardware will 5751 * pace out more rapidly then we 5752 * really want and then we 5753 * will have a long delay. Lets just keep 5754 * the same TSO size so its as if 5755 * we were not using hdwr pacing (we 5756 * just gain a bit of spacing from the 5757 * hardware if seg_sz > 1). 5758 */ 5759 seg_sz = bbr->r_ctl.rc_pace_max_segs; 5760 } 5761 if (seg_sz > bbr->r_ctl.rc_pace_max_segs) 5762 new_tso = seg_sz; 5763 else 5764 new_tso = bbr->r_ctl.rc_pace_max_segs; 5765 if (new_tso >= (PACE_MAX_IP_BYTES-maxseg)) 5766 new_tso = PACE_MAX_IP_BYTES - maxseg; 5767 5768 if (new_tso != bbr->r_ctl.rc_pace_max_segs) { 5769 bbr_log_type_tsosize(bbr, cts, new_tso, 0, bbr->r_ctl.rc_pace_max_segs, maxseg, 0); 5770 bbr->r_ctl.rc_pace_max_segs = new_tso; 5771 } 5772 } 5773 5774 static void 5775 tcp_bbr_tso_size_check(struct tcp_bbr *bbr, uint32_t cts) 5776 { 5777 uint64_t bw; 5778 uint32_t old_tso = 0, new_tso; 5779 uint32_t maxseg, bytes; 5780 uint32_t tls_seg=0; 5781 /* 5782 * Google/linux uses the following algorithm to determine 5783 * the TSO size based on the b/w of the link (from Neal Cardwell email 9/27/18): 5784 * 5785 * bytes = bw_in_bytes_per_second / 1000 5786 * bytes = min(bytes, 64k) 5787 * tso_segs = bytes / MSS 5788 * if (bw < 1.2Mbs) 5789 * min_tso_segs = 1 5790 * else 5791 * min_tso_segs = 2 5792 * tso_segs = max(tso_segs, min_tso_segs) 5793 * 5794 * * Note apply a device specific limit (we apply this in the 5795 * tcp_m_copym). 5796 * Note that before the initial measurement is made google bursts out 5797 * a full iwnd just like new-reno/cubic. 5798 * 5799 * We do not use this algorithm. Instead we 5800 * use a two phased approach: 5801 * 5802 * if ( bw <= per-tcb-cross-over) 5803 * goal_tso = calculate how much with this bw we 5804 * can send in goal-time seconds. 5805 * if (goal_tso > mss) 5806 * seg = goal_tso / mss 5807 * tso = seg * mss 5808 * else 5809 * tso = mss 5810 * if (tso > per-tcb-max) 5811 * tso = per-tcb-max 5812 * else if ( bw > 512Mbps) 5813 * tso = max-tso (64k/mss) 5814 * else 5815 * goal_tso = bw / per-tcb-divsor 5816 * seg = (goal_tso + mss-1)/mss 5817 * tso = seg * mss 5818 * 5819 * if (tso < per-tcb-floor) 5820 * tso = per-tcb-floor 5821 * if (tso > per-tcb-utter_max) 5822 * tso = per-tcb-utter_max 5823 * 5824 * Note the default per-tcb-divisor is 1000 (same as google). 5825 * the goal cross over is 30Mbps however. To recreate googles 5826 * algorithm you need to set: 5827 * 5828 * cross-over = 23,168,000 bps 5829 * goal-time = 18000 5830 * per-tcb-max = 2 5831 * per-tcb-divisor = 1000 5832 * per-tcb-floor = 1 5833 * 5834 * This will get you "google bbr" behavior with respect to tso size. 5835 * 5836 * Note we do set anything TSO size until we are past the initial 5837 * window. Before that we gnerally use either a single MSS 5838 * or we use the full IW size (so we burst a IW at a time) 5839 * Also note that Hardware-TLS is special and does alternate 5840 * things to minimize PCI Bus Bandwidth use. 5841 */ 5842 5843 if (bbr->rc_tp->t_maxseg > bbr->rc_last_options) { 5844 maxseg = bbr->rc_tp->t_maxseg - bbr->rc_last_options; 5845 } else { 5846 maxseg = BBR_MIN_SEG - bbr->rc_last_options; 5847 } 5848 #ifdef KERN_TLS 5849 if (bbr->rc_inp->inp_socket->so_snd.sb_flags & SB_TLS_IFNET) { 5850 tls_seg = ctf_get_opt_tls_size(bbr->rc_inp->inp_socket, bbr->rc_tp->snd_wnd); 5851 bbr->r_ctl.rc_pace_min_segs = (tls_seg + bbr->rc_last_options); 5852 } 5853 #endif 5854 old_tso = bbr->r_ctl.rc_pace_max_segs; 5855 if (bbr->rc_past_init_win == 0) { 5856 /* 5857 * Not enough data has been acknowledged to make a 5858 * judgement unless we are hardware TLS. Set up 5859 * the inital TSO based on if we are sending a 5860 * full IW at once or not. 5861 */ 5862 if (bbr->rc_use_google) 5863 bbr->r_ctl.rc_pace_max_segs = ((bbr->rc_tp->t_maxseg - bbr->rc_last_options) * 2); 5864 else if (bbr->bbr_init_win_cheat) 5865 bbr->r_ctl.rc_pace_max_segs = bbr_initial_cwnd(bbr, bbr->rc_tp); 5866 else 5867 bbr->r_ctl.rc_pace_max_segs = bbr->rc_tp->t_maxseg - bbr->rc_last_options; 5868 if (bbr->r_ctl.rc_pace_min_segs != bbr->rc_tp->t_maxseg) 5869 bbr->r_ctl.rc_pace_min_segs = bbr->rc_tp->t_maxseg; 5870 #ifdef KERN_TLS 5871 if ((bbr->rc_inp->inp_socket->so_snd.sb_flags & SB_TLS_IFNET) && tls_seg) { 5872 /* 5873 * For hardware TLS we set our min to the tls_seg size. 5874 */ 5875 bbr->r_ctl.rc_pace_max_segs = tls_seg; 5876 bbr->r_ctl.rc_pace_min_segs = tls_seg + bbr->rc_last_options; 5877 } 5878 #endif 5879 if (bbr->r_ctl.rc_pace_max_segs == 0) { 5880 bbr->r_ctl.rc_pace_max_segs = maxseg; 5881 } 5882 bbr_log_type_tsosize(bbr, cts, bbr->r_ctl.rc_pace_max_segs, tls_seg, old_tso, maxseg, 0); 5883 #ifdef KERN_TLS 5884 if ((bbr->rc_inp->inp_socket->so_snd.sb_flags & SB_TLS_IFNET) == 0) 5885 #endif 5886 bbr_adjust_for_hw_pacing(bbr, cts); 5887 return; 5888 } 5889 /** 5890 * Now lets set the TSO goal based on our delivery rate in 5891 * bytes per second. Note we only do this if 5892 * we have acked at least the initial cwnd worth of data. 5893 */ 5894 bw = bbr_get_bw(bbr); 5895 if (IN_RECOVERY(bbr->rc_tp->t_flags) && 5896 (bbr->rc_use_google == 0)) { 5897 /* We clamp to one MSS in recovery */ 5898 new_tso = maxseg; 5899 } else if (bbr->rc_use_google) { 5900 int min_tso_segs; 5901 5902 /* Google considers the gain too */ 5903 if (bbr->r_ctl.rc_bbr_hptsi_gain != BBR_UNIT) { 5904 bw *= bbr->r_ctl.rc_bbr_hptsi_gain; 5905 bw /= BBR_UNIT; 5906 } 5907 bytes = bw / 1024; 5908 if (bytes > (64 * 1024)) 5909 bytes = 64 * 1024; 5910 new_tso = bytes / maxseg; 5911 if (bw < ONE_POINT_TWO_MEG) 5912 min_tso_segs = 1; 5913 else 5914 min_tso_segs = 2; 5915 if (new_tso < min_tso_segs) 5916 new_tso = min_tso_segs; 5917 new_tso *= maxseg; 5918 } else if (bbr->rc_no_pacing) { 5919 new_tso = (PACE_MAX_IP_BYTES / maxseg) * maxseg; 5920 } else if (bw <= bbr->r_ctl.bbr_cross_over) { 5921 /* 5922 * Calculate the worse case b/w TSO if we are inserting no 5923 * more than a delay_target number of TSO's. 5924 */ 5925 uint32_t tso_len, min_tso; 5926 5927 tso_len = bbr_get_pacing_length(bbr, BBR_UNIT, bbr->r_ctl.bbr_hptsi_segments_delay_tar, bw); 5928 if (tso_len > maxseg) { 5929 new_tso = tso_len / maxseg; 5930 if (new_tso > bbr->r_ctl.bbr_hptsi_segments_max) 5931 new_tso = bbr->r_ctl.bbr_hptsi_segments_max; 5932 new_tso *= maxseg; 5933 } else { 5934 /* 5935 * less than a full sized frame yikes.. long rtt or 5936 * low bw? 5937 */ 5938 min_tso = bbr_minseg(bbr); 5939 if ((tso_len > min_tso) && (bbr_all_get_min == 0)) 5940 new_tso = rounddown(tso_len, min_tso); 5941 else 5942 new_tso = min_tso; 5943 } 5944 } else if (bw > FIVETWELVE_MBPS) { 5945 /* 5946 * This guy is so fast b/w wise that we can TSO as large as 5947 * possible of segments that the NIC will allow. 5948 */ 5949 new_tso = rounddown(PACE_MAX_IP_BYTES, maxseg); 5950 } else { 5951 /* 5952 * This formula is based on attempting to send a segment or 5953 * more every bbr_hptsi_per_second. The default is 1000 5954 * which means you are targeting what you can send every 1ms 5955 * based on the peers bw. 5956 * 5957 * If the number drops to say 500, then you are looking more 5958 * at 2ms and you will raise how much we send in a single 5959 * TSO thus saving CPU (less bbr_output_wtime() calls). The 5960 * trade off of course is you will send more at once and 5961 * thus tend to clump up the sends into larger "bursts" 5962 * building a queue. 5963 */ 5964 bw /= bbr->r_ctl.bbr_hptsi_per_second; 5965 new_tso = roundup(bw, (uint64_t)maxseg); 5966 /* 5967 * Gate the floor to match what our lower than 48Mbps 5968 * algorithm does. The ceiling (bbr_hptsi_segments_max) thus 5969 * becomes the floor for this calculation. 5970 */ 5971 if (new_tso < (bbr->r_ctl.bbr_hptsi_segments_max * maxseg)) 5972 new_tso = (bbr->r_ctl.bbr_hptsi_segments_max * maxseg); 5973 } 5974 if (bbr->r_ctl.bbr_hptsi_segments_floor && (new_tso < (maxseg * bbr->r_ctl.bbr_hptsi_segments_floor))) 5975 new_tso = maxseg * bbr->r_ctl.bbr_hptsi_segments_floor; 5976 if (new_tso > PACE_MAX_IP_BYTES) 5977 new_tso = rounddown(PACE_MAX_IP_BYTES, maxseg); 5978 /* Enforce an utter maximum if we are not HW-TLS */ 5979 #ifdef KERN_TLS 5980 if ((bbr->rc_inp->inp_socket->so_snd.sb_flags & SB_TLS_IFNET) == 0) 5981 #endif 5982 if (bbr->r_ctl.bbr_utter_max && (new_tso > (bbr->r_ctl.bbr_utter_max * maxseg))) { 5983 new_tso = bbr->r_ctl.bbr_utter_max * maxseg; 5984 } 5985 #ifdef KERN_TLS 5986 if (tls_seg) { 5987 /* 5988 * Lets move the output size 5989 * up to 1 or more TLS record sizes. 5990 */ 5991 uint32_t temp; 5992 5993 temp = roundup(new_tso, tls_seg); 5994 new_tso = temp; 5995 /* Back down if needed to under a full frame */ 5996 while (new_tso > PACE_MAX_IP_BYTES) 5997 new_tso -= tls_seg; 5998 } 5999 #endif 6000 if (old_tso != new_tso) { 6001 /* Only log changes */ 6002 bbr_log_type_tsosize(bbr, cts, new_tso, tls_seg, old_tso, maxseg, 0); 6003 bbr->r_ctl.rc_pace_max_segs = new_tso; 6004 } 6005 #ifdef KERN_TLS 6006 if ((bbr->rc_inp->inp_socket->so_snd.sb_flags & SB_TLS_IFNET) && 6007 tls_seg) { 6008 bbr->r_ctl.rc_pace_min_segs = tls_seg + bbr->rc_last_options; 6009 } else 6010 #endif 6011 /* We have hardware pacing and not hardware TLS! */ 6012 bbr_adjust_for_hw_pacing(bbr, cts); 6013 } 6014 6015 static void 6016 bbr_log_output(struct tcp_bbr *bbr, struct tcpcb *tp, struct tcpopt *to, int32_t len, 6017 uint32_t seq_out, uint8_t th_flags, int32_t err, uint32_t cts, 6018 struct mbuf *mb, int32_t * abandon, struct bbr_sendmap *hintrsm, uint32_t delay_calc, 6019 struct sockbuf *sb) 6020 { 6021 6022 struct bbr_sendmap *rsm, *nrsm; 6023 register uint32_t snd_max, snd_una; 6024 uint32_t pacing_time; 6025 /* 6026 * Add to the RACK log of packets in flight or retransmitted. If 6027 * there is a TS option we will use the TS echoed, if not we will 6028 * grab a TS. 6029 * 6030 * Retransmissions will increment the count and move the ts to its 6031 * proper place. Note that if options do not include TS's then we 6032 * won't be able to effectively use the ACK for an RTT on a retran. 6033 * 6034 * Notes about r_start and r_end. Lets consider a send starting at 6035 * sequence 1 for 10 bytes. In such an example the r_start would be 6036 * 1 (starting sequence) but the r_end would be r_start+len i.e. 11. 6037 * This means that r_end is actually the first sequence for the next 6038 * slot (11). 6039 * 6040 */ 6041 INP_WLOCK_ASSERT(tp->t_inpcb); 6042 if (err) { 6043 /* 6044 * We don't log errors -- we could but snd_max does not 6045 * advance in this case either. 6046 */ 6047 return; 6048 } 6049 if (th_flags & TH_RST) { 6050 /* 6051 * We don't log resets and we return immediately from 6052 * sending 6053 */ 6054 *abandon = 1; 6055 return; 6056 } 6057 snd_una = tp->snd_una; 6058 if (th_flags & (TH_SYN | TH_FIN) && (hintrsm == NULL)) { 6059 /* 6060 * The call to bbr_log_output is made before bumping 6061 * snd_max. This means we can record one extra byte on a SYN 6062 * or FIN if seq_out is adding more on and a FIN is present 6063 * (and we are not resending). 6064 */ 6065 if (th_flags & TH_SYN) 6066 len++; 6067 if (th_flags & TH_FIN) 6068 len++; 6069 } 6070 if (SEQ_LEQ((seq_out + len), snd_una)) { 6071 /* Are sending an old segment to induce an ack (keep-alive)? */ 6072 return; 6073 } 6074 if (SEQ_LT(seq_out, snd_una)) { 6075 /* huh? should we panic? */ 6076 uint32_t end; 6077 6078 end = seq_out + len; 6079 seq_out = snd_una; 6080 len = end - seq_out; 6081 } 6082 snd_max = tp->snd_max; 6083 if (len == 0) { 6084 /* We don't log zero window probes */ 6085 return; 6086 } 6087 pacing_time = bbr_get_pacing_delay(bbr, bbr->r_ctl.rc_bbr_hptsi_gain, len, cts, 1); 6088 /* First question is it a retransmission? */ 6089 if (seq_out == snd_max) { 6090 again: 6091 rsm = bbr_alloc(bbr); 6092 if (rsm == NULL) { 6093 return; 6094 } 6095 rsm->r_flags = 0; 6096 if (th_flags & TH_SYN) 6097 rsm->r_flags |= BBR_HAS_SYN; 6098 if (th_flags & TH_FIN) 6099 rsm->r_flags |= BBR_HAS_FIN; 6100 rsm->r_tim_lastsent[0] = cts; 6101 rsm->r_rtr_cnt = 1; 6102 rsm->r_rtr_bytes = 0; 6103 rsm->r_start = seq_out; 6104 rsm->r_end = rsm->r_start + len; 6105 rsm->r_dupack = 0; 6106 rsm->r_delivered = bbr->r_ctl.rc_delivered; 6107 rsm->r_pacing_delay = pacing_time; 6108 rsm->r_ts_valid = bbr->rc_ts_valid; 6109 if (bbr->rc_ts_valid) 6110 rsm->r_del_ack_ts = bbr->r_ctl.last_inbound_ts; 6111 rsm->r_del_time = bbr->r_ctl.rc_del_time; 6112 if (bbr->r_ctl.r_app_limited_until) 6113 rsm->r_app_limited = 1; 6114 else 6115 rsm->r_app_limited = 0; 6116 rsm->r_first_sent_time = bbr_get_earliest_send_outstanding(bbr, rsm, cts); 6117 rsm->r_flight_at_send = ctf_flight_size(bbr->rc_tp, 6118 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 6119 /* 6120 * Here we must also add in this rsm since snd_max 6121 * is updated after we return from a new send. 6122 */ 6123 rsm->r_flight_at_send += len; 6124 TAILQ_INSERT_TAIL(&bbr->r_ctl.rc_map, rsm, r_next); 6125 TAILQ_INSERT_TAIL(&bbr->r_ctl.rc_tmap, rsm, r_tnext); 6126 rsm->r_in_tmap = 1; 6127 if (bbr->rc_bbr_state == BBR_STATE_PROBE_BW) 6128 rsm->r_bbr_state = bbr_state_val(bbr); 6129 else 6130 rsm->r_bbr_state = 8; 6131 if (bbr->r_ctl.rc_bbr_hptsi_gain > BBR_UNIT) { 6132 rsm->r_is_gain = 1; 6133 rsm->r_is_drain = 0; 6134 } else if (bbr->r_ctl.rc_bbr_hptsi_gain < BBR_UNIT) { 6135 rsm->r_is_drain = 1; 6136 rsm->r_is_gain = 0; 6137 } else { 6138 rsm->r_is_drain = 0; 6139 rsm->r_is_gain = 0; 6140 } 6141 return; 6142 } 6143 /* 6144 * If we reach here its a retransmission and we need to find it. 6145 */ 6146 more: 6147 if (hintrsm && (hintrsm->r_start == seq_out)) { 6148 rsm = hintrsm; 6149 hintrsm = NULL; 6150 } else if (bbr->r_ctl.rc_next) { 6151 /* We have a hint from a previous run */ 6152 rsm = bbr->r_ctl.rc_next; 6153 } else { 6154 /* No hints sorry */ 6155 rsm = NULL; 6156 } 6157 if ((rsm) && (rsm->r_start == seq_out)) { 6158 /* 6159 * We used rc_next or hintrsm to retransmit, hopefully the 6160 * likely case. 6161 */ 6162 seq_out = bbr_update_entry(tp, bbr, rsm, cts, &len, pacing_time); 6163 if (len == 0) { 6164 return; 6165 } else { 6166 goto more; 6167 } 6168 } 6169 /* Ok it was not the last pointer go through it the hard way. */ 6170 TAILQ_FOREACH(rsm, &bbr->r_ctl.rc_map, r_next) { 6171 if (rsm->r_start == seq_out) { 6172 seq_out = bbr_update_entry(tp, bbr, rsm, cts, &len, pacing_time); 6173 bbr->r_ctl.rc_next = TAILQ_NEXT(rsm, r_next); 6174 if (len == 0) { 6175 return; 6176 } else { 6177 continue; 6178 } 6179 } 6180 if (SEQ_GEQ(seq_out, rsm->r_start) && SEQ_LT(seq_out, rsm->r_end)) { 6181 /* Transmitted within this piece */ 6182 /* 6183 * Ok we must split off the front and then let the 6184 * update do the rest 6185 */ 6186 nrsm = bbr_alloc_full_limit(bbr); 6187 if (nrsm == NULL) { 6188 bbr_update_rsm(tp, bbr, rsm, cts, pacing_time); 6189 return; 6190 } 6191 /* 6192 * copy rsm to nrsm and then trim the front of rsm 6193 * to not include this part. 6194 */ 6195 bbr_clone_rsm(bbr, nrsm, rsm, seq_out); 6196 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_map, rsm, nrsm, r_next); 6197 if (rsm->r_in_tmap) { 6198 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, rsm, nrsm, r_tnext); 6199 nrsm->r_in_tmap = 1; 6200 } 6201 rsm->r_flags &= (~BBR_HAS_FIN); 6202 seq_out = bbr_update_entry(tp, bbr, nrsm, cts, &len, pacing_time); 6203 if (len == 0) { 6204 return; 6205 } 6206 } 6207 } 6208 /* 6209 * Hmm not found in map did they retransmit both old and on into the 6210 * new? 6211 */ 6212 if (seq_out == tp->snd_max) { 6213 goto again; 6214 } else if (SEQ_LT(seq_out, tp->snd_max)) { 6215 #ifdef BBR_INVARIANTS 6216 printf("seq_out:%u len:%d snd_una:%u snd_max:%u -- but rsm not found?\n", 6217 seq_out, len, tp->snd_una, tp->snd_max); 6218 printf("Starting Dump of all rack entries\n"); 6219 TAILQ_FOREACH(rsm, &bbr->r_ctl.rc_map, r_next) { 6220 printf("rsm:%p start:%u end:%u\n", 6221 rsm, rsm->r_start, rsm->r_end); 6222 } 6223 printf("Dump complete\n"); 6224 panic("seq_out not found rack:%p tp:%p", 6225 bbr, tp); 6226 #endif 6227 } else { 6228 #ifdef BBR_INVARIANTS 6229 /* 6230 * Hmm beyond sndmax? (only if we are using the new rtt-pack 6231 * flag) 6232 */ 6233 panic("seq_out:%u(%d) is beyond snd_max:%u tp:%p", 6234 seq_out, len, tp->snd_max, tp); 6235 #endif 6236 } 6237 } 6238 6239 static void 6240 bbr_collapse_rtt(struct tcpcb *tp, struct tcp_bbr *bbr, int32_t rtt) 6241 { 6242 /* 6243 * Collapse timeout back the cum-ack moved. 6244 */ 6245 tp->t_rxtshift = 0; 6246 tp->t_softerror = 0; 6247 } 6248 6249 6250 static void 6251 tcp_bbr_xmit_timer(struct tcp_bbr *bbr, uint32_t rtt_usecs, uint32_t rsm_send_time, uint32_t r_start, uint32_t tsin) 6252 { 6253 bbr->rtt_valid = 1; 6254 bbr->r_ctl.cur_rtt = rtt_usecs; 6255 bbr->r_ctl.ts_in = tsin; 6256 if (rsm_send_time) 6257 bbr->r_ctl.cur_rtt_send_time = rsm_send_time; 6258 } 6259 6260 static void 6261 bbr_make_timestamp_determination(struct tcp_bbr *bbr) 6262 { 6263 /** 6264 * We have in our bbr control: 6265 * 1) The timestamp we started observing cum-acks (bbr->r_ctl.bbr_ts_check_tstmp). 6266 * 2) Our timestamp indicating when we sent that packet (bbr->r_ctl.rsm->bbr_ts_check_our_cts). 6267 * 3) The current timestamp that just came in (bbr->r_ctl.last_inbound_ts) 6268 * 4) The time that the packet that generated that ack was sent (bbr->r_ctl.cur_rtt_send_time) 6269 * 6270 * Now we can calculate the time between the sends by doing: 6271 * 6272 * delta = bbr->r_ctl.cur_rtt_send_time - bbr->r_ctl.bbr_ts_check_our_cts 6273 * 6274 * And the peer's time between receiving them by doing: 6275 * 6276 * peer_delta = bbr->r_ctl.last_inbound_ts - bbr->r_ctl.bbr_ts_check_tstmp 6277 * 6278 * We want to figure out if the timestamp values are in msec, 10msec or usec. 6279 * We also may find that we can't use the timestamps if say we see 6280 * that the peer_delta indicates that though we may have taken 10ms to 6281 * pace out the data, it only saw 1ms between the two packets. This would 6282 * indicate that somewhere on the path is a batching entity that is giving 6283 * out time-slices of the actual b/w. This would mean we could not use 6284 * reliably the peers timestamps. 6285 * 6286 * We expect delta > peer_delta initially. Until we figure out the 6287 * timestamp difference which we will store in bbr->r_ctl.bbr_peer_tsratio. 6288 * If we place 1000 there then its a ms vs our usec. If we place 10000 there 6289 * then its 10ms vs our usec. If the peer is running a usec clock we would 6290 * put a 1 there. If the value is faster then ours, we will disable the 6291 * use of timestamps (though we could revist this later if we find it to be not 6292 * just an isolated one or two flows)). 6293 * 6294 * To detect the batching middle boxes we will come up with our compensation and 6295 * if with it in place, we find the peer is drastically off (by some margin) in 6296 * the smaller direction, then we will assume the worst case and disable use of timestamps. 6297 * 6298 */ 6299 uint64_t delta, peer_delta, delta_up; 6300 6301 delta = bbr->r_ctl.cur_rtt_send_time - bbr->r_ctl.bbr_ts_check_our_cts; 6302 if (delta < bbr_min_usec_delta) { 6303 /* 6304 * Have not seen a min amount of time 6305 * between our send times so we can 6306 * make a determination of the timestamp 6307 * yet. 6308 */ 6309 return; 6310 } 6311 peer_delta = bbr->r_ctl.last_inbound_ts - bbr->r_ctl.bbr_ts_check_tstmp; 6312 if (peer_delta < bbr_min_peer_delta) { 6313 /* 6314 * We may have enough in the form of 6315 * our delta but the peers number 6316 * has not changed that much. It could 6317 * be its clock ratio is such that 6318 * we need more data (10ms tick) or 6319 * there may be other compression scenarios 6320 * going on. In any event we need the 6321 * spread to be larger. 6322 */ 6323 return; 6324 } 6325 /* Ok lets first see which way our delta is going */ 6326 if (peer_delta > delta) { 6327 /* Very unlikely, the peer without 6328 * compensation shows that it saw 6329 * the two sends arrive further apart 6330 * then we saw then in micro-seconds. 6331 */ 6332 if (peer_delta < (delta + ((delta * (uint64_t)1000)/ (uint64_t)bbr_delta_percent))) { 6333 /* well it looks like the peer is a micro-second clock. */ 6334 bbr->rc_ts_clock_set = 1; 6335 bbr->r_ctl.bbr_peer_tsratio = 1; 6336 } else { 6337 bbr->rc_ts_cant_be_used = 1; 6338 bbr->rc_ts_clock_set = 1; 6339 } 6340 return; 6341 } 6342 /* Ok we know that the peer_delta is smaller than our send distance */ 6343 bbr->rc_ts_clock_set = 1; 6344 /* First question is it within the percentage that they are using usec time? */ 6345 delta_up = (peer_delta * 1000) / (uint64_t)bbr_delta_percent; 6346 if ((peer_delta + delta_up) >= delta) { 6347 /* Its a usec clock */ 6348 bbr->r_ctl.bbr_peer_tsratio = 1; 6349 bbr_log_tstmp_validation(bbr, peer_delta, delta); 6350 return; 6351 } 6352 /* Ok if not usec, what about 10usec (though unlikely)? */ 6353 delta_up = (peer_delta * 1000 * 10) / (uint64_t)bbr_delta_percent; 6354 if (((peer_delta * 10) + delta_up) >= delta) { 6355 bbr->r_ctl.bbr_peer_tsratio = 10; 6356 bbr_log_tstmp_validation(bbr, peer_delta, delta); 6357 return; 6358 } 6359 /* And what about 100usec (though again unlikely)? */ 6360 delta_up = (peer_delta * 1000 * 100) / (uint64_t)bbr_delta_percent; 6361 if (((peer_delta * 100) + delta_up) >= delta) { 6362 bbr->r_ctl.bbr_peer_tsratio = 100; 6363 bbr_log_tstmp_validation(bbr, peer_delta, delta); 6364 return; 6365 } 6366 /* And how about 1 msec (the most likely one)? */ 6367 delta_up = (peer_delta * 1000 * 1000) / (uint64_t)bbr_delta_percent; 6368 if (((peer_delta * 1000) + delta_up) >= delta) { 6369 bbr->r_ctl.bbr_peer_tsratio = 1000; 6370 bbr_log_tstmp_validation(bbr, peer_delta, delta); 6371 return; 6372 } 6373 /* Ok if not msec could it be 10 msec? */ 6374 delta_up = (peer_delta * 1000 * 10000) / (uint64_t)bbr_delta_percent; 6375 if (((peer_delta * 10000) + delta_up) >= delta) { 6376 bbr->r_ctl.bbr_peer_tsratio = 10000; 6377 return; 6378 } 6379 /* If we fall down here the clock tick so slowly we can't use it */ 6380 bbr->rc_ts_cant_be_used = 1; 6381 bbr->r_ctl.bbr_peer_tsratio = 0; 6382 bbr_log_tstmp_validation(bbr, peer_delta, delta); 6383 } 6384 6385 /* 6386 * Collect new round-trip time estimate 6387 * and update averages and current timeout. 6388 */ 6389 static void 6390 tcp_bbr_xmit_timer_commit(struct tcp_bbr *bbr, struct tcpcb *tp, uint32_t cts) 6391 { 6392 int32_t delta; 6393 uint32_t rtt, tsin; 6394 int32_t rtt_ticks; 6395 6396 6397 if (bbr->rtt_valid == 0) 6398 /* No valid sample */ 6399 return; 6400 6401 rtt = bbr->r_ctl.cur_rtt; 6402 tsin = bbr->r_ctl.ts_in; 6403 if (bbr->rc_prtt_set_ts) { 6404 /* 6405 * We are to force feed the rttProp filter due 6406 * to an entry into PROBE_RTT. This assures 6407 * that the times are sync'd between when we 6408 * go into PROBE_RTT and the filter expiration. 6409 * 6410 * Google does not use a true filter, so they do 6411 * this implicitly since they only keep one value 6412 * and when they enter probe-rtt they update the 6413 * value to the newest rtt. 6414 */ 6415 uint32_t rtt_prop; 6416 6417 bbr->rc_prtt_set_ts = 0; 6418 rtt_prop = get_filter_value_small(&bbr->r_ctl.rc_rttprop); 6419 if (rtt > rtt_prop) 6420 filter_increase_by_small(&bbr->r_ctl.rc_rttprop, (rtt - rtt_prop), cts); 6421 else 6422 apply_filter_min_small(&bbr->r_ctl.rc_rttprop, rtt, cts); 6423 } 6424 if (bbr->rc_ack_was_delayed) 6425 rtt += bbr->r_ctl.rc_ack_hdwr_delay; 6426 6427 if (rtt < bbr->r_ctl.rc_lowest_rtt) 6428 bbr->r_ctl.rc_lowest_rtt = rtt; 6429 bbr_log_rtt_sample(bbr, rtt, tsin); 6430 if (bbr->r_init_rtt) { 6431 /* 6432 * The initial rtt is not-trusted, nuke it and lets get 6433 * our first valid measurement in. 6434 */ 6435 bbr->r_init_rtt = 0; 6436 tp->t_srtt = 0; 6437 } 6438 if ((bbr->rc_ts_clock_set == 0) && bbr->rc_ts_valid) { 6439 /* 6440 * So we have not yet figured out 6441 * what the peers TSTMP value is 6442 * in (most likely ms). We need a 6443 * series of cum-ack's to determine 6444 * this reliably. 6445 */ 6446 if (bbr->rc_ack_is_cumack) { 6447 if (bbr->rc_ts_data_set) { 6448 /* Lets attempt to determine the timestamp granularity. */ 6449 bbr_make_timestamp_determination(bbr); 6450 } else { 6451 bbr->rc_ts_data_set = 1; 6452 bbr->r_ctl.bbr_ts_check_tstmp = bbr->r_ctl.last_inbound_ts; 6453 bbr->r_ctl.bbr_ts_check_our_cts = bbr->r_ctl.cur_rtt_send_time; 6454 } 6455 } else { 6456 /* 6457 * We have to have consecutive acks 6458 * reset any "filled" state to none. 6459 */ 6460 bbr->rc_ts_data_set = 0; 6461 } 6462 } 6463 /* Round it up */ 6464 rtt_ticks = USEC_2_TICKS((rtt + (USECS_IN_MSEC - 1))); 6465 if (rtt_ticks == 0) 6466 rtt_ticks = 1; 6467 if (tp->t_srtt != 0) { 6468 /* 6469 * srtt is stored as fixed point with 5 bits after the 6470 * binary point (i.e., scaled by 8). The following magic is 6471 * equivalent to the smoothing algorithm in rfc793 with an 6472 * alpha of .875 (srtt = rtt/8 + srtt*7/8 in fixed point). 6473 * Adjust rtt to origin 0. 6474 */ 6475 6476 delta = ((rtt_ticks - 1) << TCP_DELTA_SHIFT) 6477 - (tp->t_srtt >> (TCP_RTT_SHIFT - TCP_DELTA_SHIFT)); 6478 6479 tp->t_srtt += delta; 6480 if (tp->t_srtt <= 0) 6481 tp->t_srtt = 1; 6482 6483 /* 6484 * We accumulate a smoothed rtt variance (actually, a 6485 * smoothed mean difference), then set the retransmit timer 6486 * to smoothed rtt + 4 times the smoothed variance. rttvar 6487 * is stored as fixed point with 4 bits after the binary 6488 * point (scaled by 16). The following is equivalent to 6489 * rfc793 smoothing with an alpha of .75 (rttvar = 6490 * rttvar*3/4 + |delta| / 4). This replaces rfc793's 6491 * wired-in beta. 6492 */ 6493 if (delta < 0) 6494 delta = -delta; 6495 delta -= tp->t_rttvar >> (TCP_RTTVAR_SHIFT - TCP_DELTA_SHIFT); 6496 tp->t_rttvar += delta; 6497 if (tp->t_rttvar <= 0) 6498 tp->t_rttvar = 1; 6499 if (tp->t_rttbest > tp->t_srtt + tp->t_rttvar) 6500 tp->t_rttbest = tp->t_srtt + tp->t_rttvar; 6501 } else { 6502 /* 6503 * No rtt measurement yet - use the unsmoothed rtt. Set the 6504 * variance to half the rtt (so our first retransmit happens 6505 * at 3*rtt). 6506 */ 6507 tp->t_srtt = rtt_ticks << TCP_RTT_SHIFT; 6508 tp->t_rttvar = rtt_ticks << (TCP_RTTVAR_SHIFT - 1); 6509 tp->t_rttbest = tp->t_srtt + tp->t_rttvar; 6510 } 6511 TCPSTAT_INC(tcps_rttupdated); 6512 tp->t_rttupdated++; 6513 #ifdef NETFLIX_STATS 6514 stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_RTT, imax(0, rtt_ticks)); 6515 #endif 6516 /* 6517 * the retransmit should happen at rtt + 4 * rttvar. Because of the 6518 * way we do the smoothing, srtt and rttvar will each average +1/2 6519 * tick of bias. When we compute the retransmit timer, we want 1/2 6520 * tick of rounding and 1 extra tick because of +-1/2 tick 6521 * uncertainty in the firing of the timer. The bias will give us 6522 * exactly the 1.5 tick we need. But, because the bias is 6523 * statistical, we have to test that we don't drop below the minimum 6524 * feasible timer (which is 2 ticks). 6525 */ 6526 TCPT_RANGESET(tp->t_rxtcur, TCP_REXMTVAL(tp), 6527 max(MSEC_2_TICKS(bbr->r_ctl.rc_min_rto_ms), rtt_ticks + 2), 6528 MSEC_2_TICKS(((uint32_t)bbr->rc_max_rto_sec) * 1000)); 6529 6530 /* 6531 * We received an ack for a packet that wasn't retransmitted; it is 6532 * probably safe to discard any error indications we've received 6533 * recently. This isn't quite right, but close enough for now (a 6534 * route might have failed after we sent a segment, and the return 6535 * path might not be symmetrical). 6536 */ 6537 tp->t_softerror = 0; 6538 rtt = (TICKS_2_USEC(bbr->rc_tp->t_srtt) >> TCP_RTT_SHIFT); 6539 if (bbr->r_ctl.bbr_smallest_srtt_this_state > rtt) 6540 bbr->r_ctl.bbr_smallest_srtt_this_state = rtt; 6541 } 6542 6543 static void 6544 bbr_earlier_retran(struct tcpcb *tp, struct tcp_bbr *bbr, struct bbr_sendmap *rsm, 6545 uint32_t t, uint32_t cts, int ack_type) 6546 { 6547 /* 6548 * For this RSM, we acknowledged the data from a previous 6549 * transmission, not the last one we made. This means we did a false 6550 * retransmit. 6551 */ 6552 if (rsm->r_flags & BBR_HAS_FIN) { 6553 /* 6554 * The sending of the FIN often is multiple sent when we 6555 * have everything outstanding ack'd. We ignore this case 6556 * since its over now. 6557 */ 6558 return; 6559 } 6560 if (rsm->r_flags & BBR_TLP) { 6561 /* 6562 * We expect TLP's to have this occur often 6563 */ 6564 bbr->rc_tlp_rtx_out = 0; 6565 return; 6566 } 6567 if (ack_type != BBR_CUM_ACKED) { 6568 /* 6569 * If it was not a cum-ack we 6570 * don't really know for sure since 6571 * the timestamp could be from some 6572 * other transmission. 6573 */ 6574 return; 6575 } 6576 6577 if (rsm->r_flags & BBR_WAS_SACKPASS) { 6578 /* 6579 * We retransmitted based on a sack and the earlier 6580 * retransmission ack'd it - re-ordering is occuring. 6581 */ 6582 BBR_STAT_INC(bbr_reorder_seen); 6583 bbr->r_ctl.rc_reorder_ts = cts; 6584 } 6585 /* Back down the loss count */ 6586 if (rsm->r_flags & BBR_MARKED_LOST) { 6587 bbr->r_ctl.rc_lost -= rsm->r_end - rsm->r_start; 6588 bbr->r_ctl.rc_lost_bytes -= rsm->r_end - rsm->r_start; 6589 rsm->r_flags &= ~BBR_MARKED_LOST; 6590 if (SEQ_GT(bbr->r_ctl.rc_lt_lost, bbr->r_ctl.rc_lost)) 6591 /* LT sampling also needs adjustment */ 6592 bbr->r_ctl.rc_lt_lost = bbr->r_ctl.rc_lost; 6593 } 6594 /***** RRS HERE ************************/ 6595 /* Do we need to do this??? */ 6596 /* bbr_reset_lt_bw_sampling(bbr, cts); */ 6597 /***** RRS HERE ************************/ 6598 BBR_STAT_INC(bbr_badfr); 6599 BBR_STAT_ADD(bbr_badfr_bytes, (rsm->r_end - rsm->r_start)); 6600 } 6601 6602 6603 static void 6604 bbr_set_reduced_rtt(struct tcp_bbr *bbr, uint32_t cts, uint32_t line) 6605 { 6606 bbr->r_ctl.rc_rtt_shrinks = cts; 6607 if (bbr_can_force_probertt && 6608 (TSTMP_GT(cts, bbr->r_ctl.last_in_probertt)) && 6609 ((cts - bbr->r_ctl.last_in_probertt) > bbr->r_ctl.rc_probertt_int)) { 6610 /* 6611 * We should enter probe-rtt its been too long 6612 * since we have been there. 6613 */ 6614 bbr_enter_probe_rtt(bbr, cts, __LINE__); 6615 } else 6616 bbr_check_probe_rtt_limits(bbr, cts); 6617 } 6618 6619 static void 6620 tcp_bbr_commit_bw(struct tcp_bbr *bbr, uint32_t cts) 6621 { 6622 uint64_t orig_bw; 6623 6624 if (bbr->r_ctl.rc_bbr_cur_del_rate == 0) { 6625 /* We never apply a zero measurment */ 6626 bbr_log_type_bbrupd(bbr, 20, cts, 0, 0, 6627 0, 0, 0, 0, 0, 0); 6628 return; 6629 } 6630 if (bbr->r_ctl.r_measurement_count < 0xffffffff) 6631 bbr->r_ctl.r_measurement_count++; 6632 orig_bw = get_filter_value(&bbr->r_ctl.rc_delrate); 6633 apply_filter_max(&bbr->r_ctl.rc_delrate, bbr->r_ctl.rc_bbr_cur_del_rate, bbr->r_ctl.rc_pkt_epoch); 6634 bbr_log_type_bbrupd(bbr, 21, cts, (uint32_t)orig_bw, 6635 (uint32_t)get_filter_value(&bbr->r_ctl.rc_delrate), 6636 0, 0, 0, 0, 0, 0); 6637 if (orig_bw && 6638 (orig_bw != get_filter_value(&bbr->r_ctl.rc_delrate))) { 6639 if (bbr->bbr_hdrw_pacing) { 6640 /* 6641 * Apply a new rate to the hardware 6642 * possibly. 6643 */ 6644 bbr_update_hardware_pacing_rate(bbr, cts); 6645 } 6646 bbr_set_state_target(bbr, __LINE__); 6647 tcp_bbr_tso_size_check(bbr, cts); 6648 if (bbr->r_recovery_bw) { 6649 bbr_setup_red_bw(bbr, cts); 6650 bbr_log_type_bw_reduce(bbr, BBR_RED_BW_USELRBW); 6651 } 6652 } else if ((orig_bw == 0) && get_filter_value(&bbr->r_ctl.rc_delrate)) 6653 tcp_bbr_tso_size_check(bbr, cts); 6654 } 6655 6656 static void 6657 bbr_nf_measurement(struct tcp_bbr *bbr, struct bbr_sendmap *rsm, uint32_t rtt, uint32_t cts) 6658 { 6659 if (bbr->rc_in_persist == 0) { 6660 /* We log only when not in persist */ 6661 /* Translate to a Bytes Per Second */ 6662 uint64_t tim, bw, ts_diff, ts_bw; 6663 uint32_t upper, lower, delivered; 6664 6665 if (TSTMP_GT(bbr->r_ctl.rc_del_time, rsm->r_del_time)) 6666 tim = (uint64_t)(bbr->r_ctl.rc_del_time - rsm->r_del_time); 6667 else 6668 tim = 1; 6669 /* 6670 * Now that we have processed the tim (skipping the sample 6671 * or possibly updating the time, go ahead and 6672 * calculate the cdr. 6673 */ 6674 delivered = (bbr->r_ctl.rc_delivered - rsm->r_delivered); 6675 bw = (uint64_t)delivered; 6676 bw *= (uint64_t)USECS_IN_SECOND; 6677 bw /= tim; 6678 if (bw == 0) { 6679 /* We must have a calculatable amount */ 6680 return; 6681 } 6682 upper = (bw >> 32) & 0x00000000ffffffff; 6683 lower = bw & 0x00000000ffffffff; 6684 /* 6685 * If we are using this b/w shove it in now so we 6686 * can see in the trace viewer if it gets over-ridden. 6687 */ 6688 if (rsm->r_ts_valid && 6689 bbr->rc_ts_valid && 6690 bbr->rc_ts_clock_set && 6691 (bbr->rc_ts_cant_be_used == 0) && 6692 bbr->rc_use_ts_limit) { 6693 ts_diff = max((bbr->r_ctl.last_inbound_ts - rsm->r_del_ack_ts), 1); 6694 ts_diff *= bbr->r_ctl.bbr_peer_tsratio; 6695 if ((delivered == 0) || 6696 (rtt < 1000)) { 6697 /* Can't use the ts */ 6698 bbr_log_type_bbrupd(bbr, 61, cts, 6699 ts_diff, 6700 bbr->r_ctl.last_inbound_ts, 6701 rsm->r_del_ack_ts, 0, 6702 0, 0, 0, delivered); 6703 } else { 6704 ts_bw = (uint64_t)delivered; 6705 ts_bw *= (uint64_t)USECS_IN_SECOND; 6706 ts_bw /= ts_diff; 6707 bbr_log_type_bbrupd(bbr, 62, cts, 6708 (ts_bw >> 32), 6709 (ts_bw & 0xffffffff), 0, 0, 6710 0, 0, ts_diff, delivered); 6711 if ((bbr->ts_can_raise) && 6712 (ts_bw > bw)) { 6713 bbr_log_type_bbrupd(bbr, 8, cts, 6714 delivered, 6715 ts_diff, 6716 (bw >> 32), 6717 (bw & 0x00000000ffffffff), 6718 0, 0, 0, 0); 6719 bw = ts_bw; 6720 } else if (ts_bw && (ts_bw < bw)) { 6721 bbr_log_type_bbrupd(bbr, 7, cts, 6722 delivered, 6723 ts_diff, 6724 (bw >> 32), 6725 (bw & 0x00000000ffffffff), 6726 0, 0, 0, 0); 6727 bw = ts_bw; 6728 } 6729 } 6730 } 6731 if (rsm->r_first_sent_time && 6732 TSTMP_GT(rsm->r_tim_lastsent[(rsm->r_rtr_cnt -1)],rsm->r_first_sent_time)) { 6733 uint64_t sbw, sti; 6734 /* 6735 * We use what was in flight at the time of our 6736 * send and the size of this send to figure 6737 * out what we have been sending at (amount). 6738 * For the time we take from the time of 6739 * the send of the first send outstanding 6740 * until this send plus this sends pacing 6741 * time. This gives us a good calculation 6742 * as to the rate we have been sending at. 6743 */ 6744 6745 sbw = (uint64_t)(rsm->r_flight_at_send); 6746 sbw *= (uint64_t)USECS_IN_SECOND; 6747 sti = rsm->r_tim_lastsent[(rsm->r_rtr_cnt -1)] - rsm->r_first_sent_time; 6748 sti += rsm->r_pacing_delay; 6749 sbw /= sti; 6750 if (sbw < bw) { 6751 bbr_log_type_bbrupd(bbr, 6, cts, 6752 delivered, 6753 (uint32_t)sti, 6754 (bw >> 32), 6755 (uint32_t)bw, 6756 rsm->r_first_sent_time, 0, (sbw >> 32), 6757 (uint32_t)sbw); 6758 bw = sbw; 6759 } 6760 } 6761 /* Use the google algorithm for b/w measurements */ 6762 bbr->r_ctl.rc_bbr_cur_del_rate = bw; 6763 if ((rsm->r_app_limited == 0) || 6764 (bw > get_filter_value(&bbr->r_ctl.rc_delrate))) { 6765 tcp_bbr_commit_bw(bbr, cts); 6766 bbr_log_type_bbrupd(bbr, 10, cts, (uint32_t)tim, delivered, 6767 0, 0, 0, 0, bbr->r_ctl.rc_del_time, rsm->r_del_time); 6768 } 6769 } 6770 } 6771 6772 static void 6773 bbr_google_measurement(struct tcp_bbr *bbr, struct bbr_sendmap *rsm, uint32_t rtt, uint32_t cts) 6774 { 6775 if (bbr->rc_in_persist == 0) { 6776 /* We log only when not in persist */ 6777 /* Translate to a Bytes Per Second */ 6778 uint64_t tim, bw; 6779 uint32_t upper, lower, delivered; 6780 int no_apply = 0; 6781 6782 if (TSTMP_GT(bbr->r_ctl.rc_del_time, rsm->r_del_time)) 6783 tim = (uint64_t)(bbr->r_ctl.rc_del_time - rsm->r_del_time); 6784 else 6785 tim = 1; 6786 /* 6787 * Now that we have processed the tim (skipping the sample 6788 * or possibly updating the time, go ahead and 6789 * calculate the cdr. 6790 */ 6791 delivered = (bbr->r_ctl.rc_delivered - rsm->r_delivered); 6792 bw = (uint64_t)delivered; 6793 bw *= (uint64_t)USECS_IN_SECOND; 6794 bw /= tim; 6795 if (tim < bbr->r_ctl.rc_lowest_rtt) { 6796 bbr_log_type_bbrupd(bbr, 99, cts, (uint32_t)tim, delivered, 6797 tim, bbr->r_ctl.rc_lowest_rtt, 0, 0, 0, 0); 6798 6799 no_apply = 1; 6800 } 6801 upper = (bw >> 32) & 0x00000000ffffffff; 6802 lower = bw & 0x00000000ffffffff; 6803 /* 6804 * If we are using this b/w shove it in now so we 6805 * can see in the trace viewer if it gets over-ridden. 6806 */ 6807 bbr->r_ctl.rc_bbr_cur_del_rate = bw; 6808 /* Gate by the sending rate */ 6809 if (rsm->r_first_sent_time && 6810 TSTMP_GT(rsm->r_tim_lastsent[(rsm->r_rtr_cnt -1)],rsm->r_first_sent_time)) { 6811 uint64_t sbw, sti; 6812 /* 6813 * We use what was in flight at the time of our 6814 * send and the size of this send to figure 6815 * out what we have been sending at (amount). 6816 * For the time we take from the time of 6817 * the send of the first send outstanding 6818 * until this send plus this sends pacing 6819 * time. This gives us a good calculation 6820 * as to the rate we have been sending at. 6821 */ 6822 6823 sbw = (uint64_t)(rsm->r_flight_at_send); 6824 sbw *= (uint64_t)USECS_IN_SECOND; 6825 sti = rsm->r_tim_lastsent[(rsm->r_rtr_cnt -1)] - rsm->r_first_sent_time; 6826 sti += rsm->r_pacing_delay; 6827 sbw /= sti; 6828 if (sbw < bw) { 6829 bbr_log_type_bbrupd(bbr, 6, cts, 6830 delivered, 6831 (uint32_t)sti, 6832 (bw >> 32), 6833 (uint32_t)bw, 6834 rsm->r_first_sent_time, 0, (sbw >> 32), 6835 (uint32_t)sbw); 6836 bw = sbw; 6837 } 6838 if ((sti > tim) && 6839 (sti < bbr->r_ctl.rc_lowest_rtt)) { 6840 bbr_log_type_bbrupd(bbr, 99, cts, (uint32_t)tim, delivered, 6841 (uint32_t)sti, bbr->r_ctl.rc_lowest_rtt, 0, 0, 0, 0); 6842 no_apply = 1; 6843 } else 6844 no_apply = 0; 6845 } 6846 bbr->r_ctl.rc_bbr_cur_del_rate = bw; 6847 if ((no_apply == 0) && 6848 ((rsm->r_app_limited == 0) || 6849 (bw > get_filter_value(&bbr->r_ctl.rc_delrate)))) { 6850 tcp_bbr_commit_bw(bbr, cts); 6851 bbr_log_type_bbrupd(bbr, 10, cts, (uint32_t)tim, delivered, 6852 0, 0, 0, 0, bbr->r_ctl.rc_del_time, rsm->r_del_time); 6853 } 6854 } 6855 } 6856 6857 6858 static void 6859 bbr_update_bbr_info(struct tcp_bbr *bbr, struct bbr_sendmap *rsm, uint32_t rtt, uint32_t cts, uint32_t tsin, 6860 uint32_t uts, int32_t match, uint32_t rsm_send_time, int32_t ack_type, struct tcpopt *to) 6861 { 6862 uint64_t old_rttprop; 6863 6864 /* Update our delivery time and amount */ 6865 bbr->r_ctl.rc_delivered += (rsm->r_end - rsm->r_start); 6866 bbr->r_ctl.rc_del_time = cts; 6867 if (rtt == 0) { 6868 /* 6869 * 0 means its a retransmit, for now we don't use these for 6870 * the rest of BBR. 6871 */ 6872 return; 6873 } 6874 if ((bbr->rc_use_google == 0) && 6875 (match != BBR_RTT_BY_EXACTMATCH) && 6876 (match != BBR_RTT_BY_TIMESTAMP)){ 6877 /* 6878 * We get a lot of rtt updates, lets not pay attention to 6879 * any that are not an exact match. That way we don't have 6880 * to worry about timestamps and the whole nonsense of 6881 * unsure if its a retransmission etc (if we ever had the 6882 * timestamp fixed to always have the last thing sent this 6883 * would not be a issue). 6884 */ 6885 return; 6886 } 6887 if ((bbr_no_retran && bbr->rc_use_google) && 6888 (match != BBR_RTT_BY_EXACTMATCH) && 6889 (match != BBR_RTT_BY_TIMESTAMP)){ 6890 /* 6891 * We only do measurements in google mode 6892 * with bbr_no_retran on for sure things. 6893 */ 6894 return; 6895 } 6896 /* Only update srtt if we know by exact match */ 6897 tcp_bbr_xmit_timer(bbr, rtt, rsm_send_time, rsm->r_start, tsin); 6898 if (ack_type == BBR_CUM_ACKED) 6899 bbr->rc_ack_is_cumack = 1; 6900 else 6901 bbr->rc_ack_is_cumack = 0; 6902 old_rttprop = bbr_get_rtt(bbr, BBR_RTT_PROP); 6903 /* 6904 * Note the following code differs to the original 6905 * BBR spec. It calls for <= not <. However after a 6906 * long discussion in email with Neal, he acknowledged 6907 * that it should be < than so that we will have flows 6908 * going into probe-rtt (we were seeing cases where that 6909 * did not happen and caused ugly things to occur). We 6910 * have added this agreed upon fix to our code base. 6911 */ 6912 if (rtt < old_rttprop) { 6913 /* Update when we last saw a rtt drop */ 6914 bbr_log_rtt_shrinks(bbr, cts, 0, rtt, __LINE__, BBR_RTTS_NEWRTT, 0); 6915 bbr_set_reduced_rtt(bbr, cts, __LINE__); 6916 } 6917 bbr_log_type_bbrrttprop(bbr, rtt, (rsm ? rsm->r_end : 0), uts, cts, 6918 match, rsm->r_start, rsm->r_flags); 6919 apply_filter_min_small(&bbr->r_ctl.rc_rttprop, rtt, cts); 6920 if (old_rttprop != bbr_get_rtt(bbr, BBR_RTT_PROP)) { 6921 /* 6922 * The RTT-prop moved, reset the target (may be a 6923 * nop for some states). 6924 */ 6925 bbr_set_state_target(bbr, __LINE__); 6926 if (bbr->rc_bbr_state == BBR_STATE_PROBE_RTT) 6927 bbr_log_rtt_shrinks(bbr, cts, 0, 0, 6928 __LINE__, BBR_RTTS_NEW_TARGET, 0); 6929 else if (old_rttprop < bbr_get_rtt(bbr, BBR_RTT_PROP)) 6930 /* It went up */ 6931 bbr_check_probe_rtt_limits(bbr, cts); 6932 } 6933 if ((bbr->rc_use_google == 0) && 6934 (match == BBR_RTT_BY_TIMESTAMP)) { 6935 /* 6936 * We don't do b/w update with 6937 * these since they are not really 6938 * reliable. 6939 */ 6940 return; 6941 } 6942 if (bbr->r_ctl.r_app_limited_until && 6943 (bbr->r_ctl.rc_delivered >= bbr->r_ctl.r_app_limited_until)) { 6944 /* We are no longer app-limited */ 6945 bbr->r_ctl.r_app_limited_until = 0; 6946 } 6947 if (bbr->rc_use_google) { 6948 bbr_google_measurement(bbr, rsm, rtt, cts); 6949 } else { 6950 bbr_nf_measurement(bbr, rsm, rtt, cts); 6951 } 6952 } 6953 6954 /* 6955 * Convert a timestamp that the main stack 6956 * uses (milliseconds) into one that bbr uses 6957 * (microseconds). Return that converted timestamp. 6958 */ 6959 static uint32_t 6960 bbr_ts_convert(uint32_t cts) { 6961 uint32_t sec, msec; 6962 6963 sec = cts / MS_IN_USEC; 6964 msec = cts - (MS_IN_USEC * sec); 6965 return ((sec * USECS_IN_SECOND) + (msec * MS_IN_USEC)); 6966 } 6967 6968 /* 6969 * Return 0 if we did not update the RTT time, return 6970 * 1 if we did. 6971 */ 6972 static int 6973 bbr_update_rtt(struct tcpcb *tp, struct tcp_bbr *bbr, 6974 struct bbr_sendmap *rsm, struct tcpopt *to, uint32_t cts, int32_t ack_type, uint32_t th_ack) 6975 { 6976 int32_t i; 6977 uint32_t t, uts = 0; 6978 6979 if ((rsm->r_flags & BBR_ACKED) || 6980 (rsm->r_flags & BBR_WAS_RENEGED) || 6981 (rsm->r_flags & BBR_RXT_CLEARED)) { 6982 /* Already done */ 6983 return (0); 6984 } 6985 if (rsm->r_rtr_cnt == 1) { 6986 /* 6987 * Only one transmit. Hopefully the normal case. 6988 */ 6989 if (TSTMP_GT(cts, rsm->r_tim_lastsent[0])) 6990 t = cts - rsm->r_tim_lastsent[0]; 6991 else 6992 t = 1; 6993 if ((int)t <= 0) 6994 t = 1; 6995 bbr->r_ctl.rc_last_rtt = t; 6996 bbr_update_bbr_info(bbr, rsm, t, cts, to->to_tsecr, 0, 6997 BBR_RTT_BY_EXACTMATCH, rsm->r_tim_lastsent[0], ack_type, to); 6998 return (1); 6999 } 7000 /* Convert to usecs */ 7001 if ((bbr_can_use_ts_for_rtt == 1) && 7002 (bbr->rc_use_google == 1) && 7003 (ack_type == BBR_CUM_ACKED) && 7004 (to->to_flags & TOF_TS) && 7005 (to->to_tsecr != 0)) { 7006 7007 t = tcp_tv_to_mssectick(&bbr->rc_tv) - to->to_tsecr; 7008 if (t < 1) 7009 t = 1; 7010 t *= MS_IN_USEC; 7011 bbr_update_bbr_info(bbr, rsm, t, cts, to->to_tsecr, 0, 7012 BBR_RTT_BY_TIMESTAMP, 7013 rsm->r_tim_lastsent[(rsm->r_rtr_cnt-1)], 7014 ack_type, to); 7015 return (1); 7016 } 7017 uts = bbr_ts_convert(to->to_tsecr); 7018 if ((to->to_flags & TOF_TS) && 7019 (to->to_tsecr != 0) && 7020 (ack_type == BBR_CUM_ACKED) && 7021 ((rsm->r_flags & BBR_OVERMAX) == 0)) { 7022 /* 7023 * Now which timestamp does it match? In this block the ACK 7024 * may be coming from a previous transmission. 7025 */ 7026 uint32_t fudge; 7027 7028 fudge = BBR_TIMER_FUDGE; 7029 for (i = 0; i < rsm->r_rtr_cnt; i++) { 7030 if ((SEQ_GEQ(uts, (rsm->r_tim_lastsent[i] - fudge))) && 7031 (SEQ_LEQ(uts, (rsm->r_tim_lastsent[i] + fudge)))) { 7032 if (TSTMP_GT(cts, rsm->r_tim_lastsent[i])) 7033 t = cts - rsm->r_tim_lastsent[i]; 7034 else 7035 t = 1; 7036 if ((int)t <= 0) 7037 t = 1; 7038 bbr->r_ctl.rc_last_rtt = t; 7039 bbr_update_bbr_info(bbr, rsm, t, cts, to->to_tsecr, uts, BBR_RTT_BY_TSMATCHING, 7040 rsm->r_tim_lastsent[i], ack_type, to); 7041 if ((i + 1) < rsm->r_rtr_cnt) { 7042 /* Likely */ 7043 bbr_earlier_retran(tp, bbr, rsm, t, cts, ack_type); 7044 } else if (rsm->r_flags & BBR_TLP) { 7045 bbr->rc_tlp_rtx_out = 0; 7046 } 7047 return (1); 7048 } 7049 } 7050 /* Fall through if we can't find a matching timestamp */ 7051 } 7052 /* 7053 * Ok its a SACK block that we retransmitted. or a windows 7054 * machine without timestamps. We can tell nothing from the 7055 * time-stamp since its not there or the time the peer last 7056 * recieved a segment that moved forward its cum-ack point. 7057 * 7058 * Lets look at the last retransmit and see what we can tell 7059 * (with BBR for space we only keep 2 note we have to keep 7060 * at least 2 so the map can not be condensed more). 7061 */ 7062 i = rsm->r_rtr_cnt - 1; 7063 if (TSTMP_GT(cts, rsm->r_tim_lastsent[i])) 7064 t = cts - rsm->r_tim_lastsent[i]; 7065 else 7066 goto not_sure; 7067 if (t < bbr->r_ctl.rc_lowest_rtt) { 7068 /* 7069 * We retransmitted and the ack came back in less 7070 * than the smallest rtt we have observed in the 7071 * windowed rtt. We most likey did an improper 7072 * retransmit as outlined in 4.2 Step 3 point 2 in 7073 * the rack-draft. 7074 * 7075 * Use the prior transmission to update all the 7076 * information as long as there is only one prior 7077 * transmission. 7078 */ 7079 if ((rsm->r_flags & BBR_OVERMAX) == 0) { 7080 #ifdef BBR_INVARIANTS 7081 if (rsm->r_rtr_cnt == 1) 7082 panic("rsm:%p bbr:%p rsm has overmax and only 1 retranmit flags:%x?", rsm, bbr, rsm->r_flags); 7083 #endif 7084 i = rsm->r_rtr_cnt - 2; 7085 if (TSTMP_GT(cts, rsm->r_tim_lastsent[i])) 7086 t = cts - rsm->r_tim_lastsent[i]; 7087 else 7088 t = 1; 7089 bbr_update_bbr_info(bbr, rsm, t, cts, to->to_tsecr, uts, BBR_RTT_BY_EARLIER_RET, 7090 rsm->r_tim_lastsent[i], ack_type, to); 7091 bbr_earlier_retran(tp, bbr, rsm, t, cts, ack_type); 7092 } else { 7093 /* 7094 * Too many prior transmissions, just 7095 * updated BBR delivered 7096 */ 7097 not_sure: 7098 bbr_update_bbr_info(bbr, rsm, 0, cts, to->to_tsecr, uts, 7099 BBR_RTT_BY_SOME_RETRAN, 0, ack_type, to); 7100 } 7101 } else { 7102 /* 7103 * We retransmitted it and the retransmit did the 7104 * job. 7105 */ 7106 if (rsm->r_flags & BBR_TLP) 7107 bbr->rc_tlp_rtx_out = 0; 7108 if ((rsm->r_flags & BBR_OVERMAX) == 0) 7109 bbr_update_bbr_info(bbr, rsm, t, cts, to->to_tsecr, uts, 7110 BBR_RTT_BY_THIS_RETRAN, 0, ack_type, to); 7111 else 7112 bbr_update_bbr_info(bbr, rsm, 0, cts, to->to_tsecr, uts, 7113 BBR_RTT_BY_SOME_RETRAN, 0, ack_type, to); 7114 return (1); 7115 } 7116 return (0); 7117 } 7118 7119 /* 7120 * Mark the SACK_PASSED flag on all entries prior to rsm send wise. 7121 */ 7122 static void 7123 bbr_log_sack_passed(struct tcpcb *tp, 7124 struct tcp_bbr *bbr, struct bbr_sendmap *rsm) 7125 { 7126 struct bbr_sendmap *nrsm; 7127 7128 nrsm = rsm; 7129 TAILQ_FOREACH_REVERSE_FROM(nrsm, &bbr->r_ctl.rc_tmap, 7130 bbr_head, r_tnext) { 7131 if (nrsm == rsm) { 7132 /* Skip orginal segment he is acked */ 7133 continue; 7134 } 7135 if (nrsm->r_flags & BBR_ACKED) { 7136 /* Skip ack'd segments */ 7137 continue; 7138 } 7139 if (nrsm->r_flags & BBR_SACK_PASSED) { 7140 /* 7141 * We found one that is already marked 7142 * passed, we have been here before and 7143 * so all others below this are marked. 7144 */ 7145 break; 7146 } 7147 BBR_STAT_INC(bbr_sack_passed); 7148 nrsm->r_flags |= BBR_SACK_PASSED; 7149 if (((nrsm->r_flags & BBR_MARKED_LOST) == 0) && 7150 bbr_is_lost(bbr, nrsm, bbr->r_ctl.rc_rcvtime)) { 7151 bbr->r_ctl.rc_lost += nrsm->r_end - nrsm->r_start; 7152 bbr->r_ctl.rc_lost_bytes += nrsm->r_end - nrsm->r_start; 7153 nrsm->r_flags |= BBR_MARKED_LOST; 7154 } 7155 nrsm->r_flags &= ~BBR_WAS_SACKPASS; 7156 } 7157 } 7158 7159 /* 7160 * Returns the number of bytes that were 7161 * newly ack'd by sack blocks. 7162 */ 7163 static uint32_t 7164 bbr_proc_sack_blk(struct tcpcb *tp, struct tcp_bbr *bbr, struct sackblk *sack, 7165 struct tcpopt *to, struct bbr_sendmap **prsm, uint32_t cts) 7166 { 7167 int32_t times = 0; 7168 uint32_t start, end, maxseg, changed = 0; 7169 struct bbr_sendmap *rsm, *nrsm; 7170 int32_t used_ref = 1; 7171 uint8_t went_back = 0, went_fwd = 0; 7172 7173 maxseg = tp->t_maxseg - bbr->rc_last_options; 7174 start = sack->start; 7175 end = sack->end; 7176 rsm = *prsm; 7177 if (rsm == NULL) 7178 used_ref = 0; 7179 7180 /* Do we locate the block behind where we last were? */ 7181 if (rsm && SEQ_LT(start, rsm->r_start)) { 7182 went_back = 1; 7183 TAILQ_FOREACH_REVERSE_FROM(rsm, &bbr->r_ctl.rc_map, bbr_head, r_next) { 7184 if (SEQ_GEQ(start, rsm->r_start) && 7185 SEQ_LT(start, rsm->r_end)) { 7186 goto do_rest_ofb; 7187 } 7188 } 7189 } 7190 start_at_beginning: 7191 went_fwd = 1; 7192 /* 7193 * Ok lets locate the block where this guy is fwd from rsm (if its 7194 * set) 7195 */ 7196 TAILQ_FOREACH_FROM(rsm, &bbr->r_ctl.rc_map, r_next) { 7197 if (SEQ_GEQ(start, rsm->r_start) && 7198 SEQ_LT(start, rsm->r_end)) { 7199 break; 7200 } 7201 } 7202 do_rest_ofb: 7203 if (rsm == NULL) { 7204 /* 7205 * This happens when we get duplicate sack blocks with the 7206 * same end. For example SACK 4: 100 SACK 3: 100 The sort 7207 * will not change there location so we would just start at 7208 * the end of the first one and get lost. 7209 */ 7210 if (tp->t_flags & TF_SENTFIN) { 7211 /* 7212 * Check to see if we have not logged the FIN that 7213 * went out. 7214 */ 7215 nrsm = TAILQ_LAST_FAST(&bbr->r_ctl.rc_map, bbr_sendmap, r_next); 7216 if (nrsm && (nrsm->r_end + 1) == tp->snd_max) { 7217 /* 7218 * Ok we did not get the FIN logged. 7219 */ 7220 nrsm->r_end++; 7221 rsm = nrsm; 7222 goto do_rest_ofb; 7223 } 7224 } 7225 if (times == 1) { 7226 #ifdef BBR_INVARIANTS 7227 panic("tp:%p bbr:%p sack:%p to:%p prsm:%p", 7228 tp, bbr, sack, to, prsm); 7229 #else 7230 goto out; 7231 #endif 7232 } 7233 times++; 7234 BBR_STAT_INC(bbr_sack_proc_restart); 7235 rsm = NULL; 7236 goto start_at_beginning; 7237 } 7238 /* Ok we have an ACK for some piece of rsm */ 7239 if (rsm->r_start != start) { 7240 /* 7241 * Need to split this in two pieces the before and after. 7242 */ 7243 if (bbr_sack_mergable(rsm, start, end)) 7244 nrsm = bbr_alloc_full_limit(bbr); 7245 else 7246 nrsm = bbr_alloc_limit(bbr, BBR_LIMIT_TYPE_SPLIT); 7247 if (nrsm == NULL) { 7248 /* We could not allocate ignore the sack */ 7249 struct sackblk blk; 7250 7251 blk.start = start; 7252 blk.end = end; 7253 sack_filter_reject(&bbr->r_ctl.bbr_sf, &blk); 7254 goto out; 7255 } 7256 bbr_clone_rsm(bbr, nrsm, rsm, start); 7257 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_map, rsm, nrsm, r_next); 7258 if (rsm->r_in_tmap) { 7259 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, rsm, nrsm, r_tnext); 7260 nrsm->r_in_tmap = 1; 7261 } 7262 rsm->r_flags &= (~BBR_HAS_FIN); 7263 rsm = nrsm; 7264 } 7265 if (SEQ_GEQ(end, rsm->r_end)) { 7266 /* 7267 * The end of this block is either beyond this guy or right 7268 * at this guy. 7269 */ 7270 if ((rsm->r_flags & BBR_ACKED) == 0) { 7271 bbr_update_rtt(tp, bbr, rsm, to, cts, BBR_SACKED, 0); 7272 changed += (rsm->r_end - rsm->r_start); 7273 bbr->r_ctl.rc_sacked += (rsm->r_end - rsm->r_start); 7274 bbr_log_sack_passed(tp, bbr, rsm); 7275 if (rsm->r_flags & BBR_MARKED_LOST) { 7276 bbr->r_ctl.rc_lost_bytes -= rsm->r_end - rsm->r_start; 7277 } 7278 /* Is Reordering occuring? */ 7279 if (rsm->r_flags & BBR_SACK_PASSED) { 7280 BBR_STAT_INC(bbr_reorder_seen); 7281 bbr->r_ctl.rc_reorder_ts = cts; 7282 if (rsm->r_flags & BBR_MARKED_LOST) { 7283 bbr->r_ctl.rc_lost -= rsm->r_end - rsm->r_start; 7284 if (SEQ_GT(bbr->r_ctl.rc_lt_lost, bbr->r_ctl.rc_lost)) 7285 /* LT sampling also needs adjustment */ 7286 bbr->r_ctl.rc_lt_lost = bbr->r_ctl.rc_lost; 7287 } 7288 } 7289 rsm->r_flags |= BBR_ACKED; 7290 rsm->r_flags &= ~(BBR_TLP|BBR_WAS_RENEGED|BBR_RXT_CLEARED|BBR_MARKED_LOST); 7291 if (rsm->r_in_tmap) { 7292 TAILQ_REMOVE(&bbr->r_ctl.rc_tmap, rsm, r_tnext); 7293 rsm->r_in_tmap = 0; 7294 } 7295 } 7296 bbr_isit_a_pkt_epoch(bbr, cts, rsm, __LINE__, BBR_SACKED); 7297 if (end == rsm->r_end) { 7298 /* This block only - done */ 7299 goto out; 7300 } 7301 /* There is more not coverend by this rsm move on */ 7302 start = rsm->r_end; 7303 nrsm = TAILQ_NEXT(rsm, r_next); 7304 rsm = nrsm; 7305 times = 0; 7306 goto do_rest_ofb; 7307 } 7308 if (rsm->r_flags & BBR_ACKED) { 7309 /* Been here done that */ 7310 goto out; 7311 } 7312 /* Ok we need to split off this one at the tail */ 7313 if (bbr_sack_mergable(rsm, start, end)) 7314 nrsm = bbr_alloc_full_limit(bbr); 7315 else 7316 nrsm = bbr_alloc_limit(bbr, BBR_LIMIT_TYPE_SPLIT); 7317 if (nrsm == NULL) { 7318 /* failed XXXrrs what can we do but loose the sack info? */ 7319 struct sackblk blk; 7320 7321 blk.start = start; 7322 blk.end = end; 7323 sack_filter_reject(&bbr->r_ctl.bbr_sf, &blk); 7324 goto out; 7325 } 7326 /* Clone it */ 7327 bbr_clone_rsm(bbr, nrsm, rsm, end); 7328 /* The sack block does not cover this guy fully */ 7329 rsm->r_flags &= (~BBR_HAS_FIN); 7330 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_map, rsm, nrsm, r_next); 7331 if (rsm->r_in_tmap) { 7332 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, rsm, nrsm, r_tnext); 7333 nrsm->r_in_tmap = 1; 7334 } 7335 nrsm->r_dupack = 0; 7336 bbr_update_rtt(tp, bbr, rsm, to, cts, BBR_SACKED, 0); 7337 bbr_isit_a_pkt_epoch(bbr, cts, rsm, __LINE__, BBR_SACKED); 7338 changed += (rsm->r_end - rsm->r_start); 7339 bbr->r_ctl.rc_sacked += (rsm->r_end - rsm->r_start); 7340 bbr_log_sack_passed(tp, bbr, rsm); 7341 /* Is Reordering occuring? */ 7342 if (rsm->r_flags & BBR_MARKED_LOST) { 7343 bbr->r_ctl.rc_lost_bytes -= rsm->r_end - rsm->r_start; 7344 } 7345 if (rsm->r_flags & BBR_SACK_PASSED) { 7346 BBR_STAT_INC(bbr_reorder_seen); 7347 bbr->r_ctl.rc_reorder_ts = cts; 7348 if (rsm->r_flags & BBR_MARKED_LOST) { 7349 bbr->r_ctl.rc_lost -= rsm->r_end - rsm->r_start; 7350 if (SEQ_GT(bbr->r_ctl.rc_lt_lost, bbr->r_ctl.rc_lost)) 7351 /* LT sampling also needs adjustment */ 7352 bbr->r_ctl.rc_lt_lost = bbr->r_ctl.rc_lost; 7353 } 7354 } 7355 rsm->r_flags &= ~(BBR_TLP|BBR_WAS_RENEGED|BBR_RXT_CLEARED|BBR_MARKED_LOST); 7356 rsm->r_flags |= BBR_ACKED; 7357 if (rsm->r_in_tmap) { 7358 TAILQ_REMOVE(&bbr->r_ctl.rc_tmap, rsm, r_tnext); 7359 rsm->r_in_tmap = 0; 7360 } 7361 out: 7362 if (rsm && (rsm->r_flags & BBR_ACKED)) { 7363 /* 7364 * Now can we merge this newly acked 7365 * block with either the previous or 7366 * next block? 7367 */ 7368 nrsm = TAILQ_NEXT(rsm, r_next); 7369 if (nrsm && 7370 (nrsm->r_flags & BBR_ACKED)) { 7371 /* yep this and next can be merged */ 7372 rsm = bbr_merge_rsm(bbr, rsm, nrsm); 7373 } 7374 /* Now what about the previous? */ 7375 nrsm = TAILQ_PREV(rsm, bbr_head, r_next); 7376 if (nrsm && 7377 (nrsm->r_flags & BBR_ACKED)) { 7378 /* yep the previous and this can be merged */ 7379 rsm = bbr_merge_rsm(bbr, nrsm, rsm); 7380 } 7381 } 7382 if (used_ref == 0) { 7383 BBR_STAT_INC(bbr_sack_proc_all); 7384 } else { 7385 BBR_STAT_INC(bbr_sack_proc_short); 7386 } 7387 if (went_fwd && went_back) { 7388 BBR_STAT_INC(bbr_sack_search_both); 7389 } else if (went_fwd) { 7390 BBR_STAT_INC(bbr_sack_search_fwd); 7391 } else if (went_back) { 7392 BBR_STAT_INC(bbr_sack_search_back); 7393 } 7394 /* Save off where the next seq is */ 7395 if (rsm) 7396 bbr->r_ctl.rc_sacklast = TAILQ_NEXT(rsm, r_next); 7397 else 7398 bbr->r_ctl.rc_sacklast = NULL; 7399 *prsm = rsm; 7400 return (changed); 7401 } 7402 7403 7404 static void inline 7405 bbr_peer_reneges(struct tcp_bbr *bbr, struct bbr_sendmap *rsm, tcp_seq th_ack) 7406 { 7407 struct bbr_sendmap *tmap; 7408 7409 BBR_STAT_INC(bbr_reneges_seen); 7410 tmap = NULL; 7411 while (rsm && (rsm->r_flags & BBR_ACKED)) { 7412 /* Its no longer sacked, mark it so */ 7413 uint32_t oflags; 7414 bbr->r_ctl.rc_sacked -= (rsm->r_end - rsm->r_start); 7415 #ifdef BBR_INVARIANTS 7416 if (rsm->r_in_tmap) { 7417 panic("bbr:%p rsm:%p flags:0x%x in tmap?", 7418 bbr, rsm, rsm->r_flags); 7419 } 7420 #endif 7421 oflags = rsm->r_flags; 7422 if (rsm->r_flags & BBR_MARKED_LOST) { 7423 bbr->r_ctl.rc_lost -= rsm->r_end - rsm->r_start; 7424 bbr->r_ctl.rc_lost_bytes -= rsm->r_end - rsm->r_start; 7425 if (SEQ_GT(bbr->r_ctl.rc_lt_lost, bbr->r_ctl.rc_lost)) 7426 /* LT sampling also needs adjustment */ 7427 bbr->r_ctl.rc_lt_lost = bbr->r_ctl.rc_lost; 7428 } 7429 rsm->r_flags &= ~(BBR_ACKED | BBR_SACK_PASSED | BBR_WAS_SACKPASS | BBR_MARKED_LOST); 7430 rsm->r_flags |= BBR_WAS_RENEGED; 7431 rsm->r_flags |= BBR_RXT_CLEARED; 7432 bbr_log_type_rsmclear(bbr, bbr->r_ctl.rc_rcvtime, rsm, oflags, __LINE__); 7433 /* Rebuild it into our tmap */ 7434 if (tmap == NULL) { 7435 TAILQ_INSERT_HEAD(&bbr->r_ctl.rc_tmap, rsm, r_tnext); 7436 tmap = rsm; 7437 } else { 7438 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, tmap, rsm, r_tnext); 7439 tmap = rsm; 7440 } 7441 tmap->r_in_tmap = 1; 7442 /* 7443 * XXXrrs Delivered? Should we do anything here? 7444 * 7445 * Of course we don't on a rxt timeout so maybe its ok that 7446 * we don't? 7447 * 7448 * For now lets not. 7449 */ 7450 rsm = TAILQ_NEXT(rsm, r_next); 7451 } 7452 /* 7453 * Now lets possibly clear the sack filter so we start recognizing 7454 * sacks that cover this area. 7455 */ 7456 sack_filter_clear(&bbr->r_ctl.bbr_sf, th_ack); 7457 } 7458 7459 static void 7460 bbr_log_syn(struct tcpcb *tp, struct tcpopt *to) 7461 { 7462 struct tcp_bbr *bbr; 7463 struct bbr_sendmap *rsm; 7464 uint32_t cts; 7465 7466 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 7467 cts = bbr->r_ctl.rc_rcvtime; 7468 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map); 7469 if (rsm && (rsm->r_flags & BBR_HAS_SYN)) { 7470 if ((rsm->r_end - rsm->r_start) <= 1) { 7471 /* Log out the SYN completely */ 7472 bbr->r_ctl.rc_holes_rxt -= rsm->r_rtr_bytes; 7473 rsm->r_rtr_bytes = 0; 7474 TAILQ_REMOVE(&bbr->r_ctl.rc_map, rsm, r_next); 7475 if (rsm->r_in_tmap) { 7476 TAILQ_REMOVE(&bbr->r_ctl.rc_tmap, rsm, r_tnext); 7477 rsm->r_in_tmap = 0; 7478 } 7479 if (bbr->r_ctl.rc_next == rsm) { 7480 /* scoot along the marker */ 7481 bbr->r_ctl.rc_next = TAILQ_FIRST(&bbr->r_ctl.rc_map); 7482 } 7483 if (to != NULL) 7484 bbr_update_rtt(tp, bbr, rsm, to, cts, BBR_CUM_ACKED, 0); 7485 bbr_free(bbr, rsm); 7486 } else { 7487 /* There is more (Fast open)? strip out SYN. */ 7488 rsm->r_flags &= ~BBR_HAS_SYN; 7489 rsm->r_start++; 7490 } 7491 } 7492 } 7493 7494 /* 7495 * Returns the number of bytes that were 7496 * acknowledged by SACK blocks. 7497 */ 7498 7499 static uint32_t 7500 bbr_log_ack(struct tcpcb *tp, struct tcpopt *to, struct tcphdr *th, 7501 uint32_t *prev_acked) 7502 { 7503 uint32_t changed, last_seq, entered_recovery = 0; 7504 struct tcp_bbr *bbr; 7505 struct bbr_sendmap *rsm; 7506 struct sackblk sack, sack_blocks[TCP_MAX_SACK + 1]; 7507 register uint32_t th_ack; 7508 int32_t i, j, k, new_sb, num_sack_blks = 0; 7509 uint32_t cts, acked, ack_point, sack_changed = 0; 7510 uint32_t p_maxseg, maxseg, p_acked = 0; 7511 7512 INP_WLOCK_ASSERT(tp->t_inpcb); 7513 if (th->th_flags & TH_RST) { 7514 /* We don't log resets */ 7515 return (0); 7516 } 7517 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 7518 cts = bbr->r_ctl.rc_rcvtime; 7519 7520 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map); 7521 changed = 0; 7522 maxseg = tp->t_maxseg - bbr->rc_last_options; 7523 p_maxseg = min(bbr->r_ctl.rc_pace_max_segs, maxseg); 7524 th_ack = th->th_ack; 7525 if (SEQ_GT(th_ack, tp->snd_una)) { 7526 acked = th_ack - tp->snd_una; 7527 bbr_log_progress_event(bbr, tp, ticks, PROGRESS_UPDATE, __LINE__); 7528 bbr->rc_tp->t_acktime = ticks; 7529 } else 7530 acked = 0; 7531 if (SEQ_LEQ(th_ack, tp->snd_una)) { 7532 /* Only sent here for sack processing */ 7533 goto proc_sack; 7534 } 7535 if (rsm && SEQ_GT(th_ack, rsm->r_start)) { 7536 changed = th_ack - rsm->r_start; 7537 } else if ((rsm == NULL) && ((th_ack - 1) == tp->iss)) { 7538 /* 7539 * For the SYN incoming case we will not have called 7540 * tcp_output for the sending of the SYN, so there will be 7541 * no map. All other cases should probably be a panic. 7542 */ 7543 if ((to->to_flags & TOF_TS) && (to->to_tsecr != 0)) { 7544 /* 7545 * We have a timestamp that can be used to generate 7546 * an initial RTT. 7547 */ 7548 uint32_t ts, now, rtt; 7549 7550 ts = bbr_ts_convert(to->to_tsecr); 7551 now = bbr_ts_convert(tcp_tv_to_mssectick(&bbr->rc_tv)); 7552 rtt = now - ts; 7553 if (rtt < 1) 7554 rtt = 1; 7555 bbr_log_type_bbrrttprop(bbr, rtt, 7556 tp->iss, 0, cts, 7557 BBR_RTT_BY_TIMESTAMP, tp->iss, 0); 7558 apply_filter_min_small(&bbr->r_ctl.rc_rttprop, rtt, cts); 7559 changed = 1; 7560 bbr->r_wanted_output = 1; 7561 goto out; 7562 } 7563 goto proc_sack; 7564 } else if (rsm == NULL) { 7565 goto out; 7566 } 7567 if (changed) { 7568 /* 7569 * The ACK point is advancing to th_ack, we must drop off 7570 * the packets in the rack log and calculate any eligble 7571 * RTT's. 7572 */ 7573 bbr->r_wanted_output = 1; 7574 more: 7575 if (rsm == NULL) { 7576 7577 if (tp->t_flags & TF_SENTFIN) { 7578 /* if we send a FIN we will not hav a map */ 7579 goto proc_sack; 7580 } 7581 #ifdef BBR_INVARIANTS 7582 panic("No rack map tp:%p for th:%p state:%d bbr:%p snd_una:%u snd_max:%u chg:%d\n", 7583 tp, 7584 th, tp->t_state, bbr, 7585 tp->snd_una, tp->snd_max, changed); 7586 #endif 7587 goto proc_sack; 7588 } 7589 } 7590 if (SEQ_LT(th_ack, rsm->r_start)) { 7591 /* Huh map is missing this */ 7592 #ifdef BBR_INVARIANTS 7593 printf("Rack map starts at r_start:%u for th_ack:%u huh? ts:%d rs:%d bbr:%p\n", 7594 rsm->r_start, 7595 th_ack, tp->t_state, 7596 bbr->r_state, bbr); 7597 panic("th-ack is bad bbr:%p tp:%p", bbr, tp); 7598 #endif 7599 goto proc_sack; 7600 } else if (th_ack == rsm->r_start) { 7601 /* None here to ack */ 7602 goto proc_sack; 7603 } 7604 /* 7605 * Clear the dup ack counter, it will 7606 * either be freed or if there is some 7607 * remaining we need to start it at zero. 7608 */ 7609 rsm->r_dupack = 0; 7610 /* Now do we consume the whole thing? */ 7611 if (SEQ_GEQ(th_ack, rsm->r_end)) { 7612 /* Its all consumed. */ 7613 uint32_t left; 7614 7615 if (rsm->r_flags & BBR_ACKED) { 7616 /* 7617 * It was acked on the scoreboard -- remove it from 7618 * total 7619 */ 7620 p_acked += (rsm->r_end - rsm->r_start); 7621 bbr->r_ctl.rc_sacked -= (rsm->r_end - rsm->r_start); 7622 if (bbr->r_ctl.rc_sacked == 0) 7623 bbr->r_ctl.rc_sacklast = NULL; 7624 } else { 7625 bbr_update_rtt(tp, bbr, rsm, to, cts, BBR_CUM_ACKED, th_ack); 7626 if (rsm->r_flags & BBR_MARKED_LOST) { 7627 bbr->r_ctl.rc_lost_bytes -= rsm->r_end - rsm->r_start; 7628 } 7629 if (rsm->r_flags & BBR_SACK_PASSED) { 7630 /* 7631 * There are acked segments ACKED on the 7632 * scoreboard further up. We are seeing 7633 * reordering. 7634 */ 7635 BBR_STAT_INC(bbr_reorder_seen); 7636 bbr->r_ctl.rc_reorder_ts = cts; 7637 if (rsm->r_flags & BBR_MARKED_LOST) { 7638 bbr->r_ctl.rc_lost -= rsm->r_end - rsm->r_start; 7639 if (SEQ_GT(bbr->r_ctl.rc_lt_lost, bbr->r_ctl.rc_lost)) 7640 /* LT sampling also needs adjustment */ 7641 bbr->r_ctl.rc_lt_lost = bbr->r_ctl.rc_lost; 7642 } 7643 } 7644 rsm->r_flags &= ~BBR_MARKED_LOST; 7645 } 7646 bbr->r_ctl.rc_holes_rxt -= rsm->r_rtr_bytes; 7647 rsm->r_rtr_bytes = 0; 7648 TAILQ_REMOVE(&bbr->r_ctl.rc_map, rsm, r_next); 7649 if (rsm->r_in_tmap) { 7650 TAILQ_REMOVE(&bbr->r_ctl.rc_tmap, rsm, r_tnext); 7651 rsm->r_in_tmap = 0; 7652 } 7653 if (bbr->r_ctl.rc_next == rsm) { 7654 /* scoot along the marker */ 7655 bbr->r_ctl.rc_next = TAILQ_FIRST(&bbr->r_ctl.rc_map); 7656 } 7657 bbr_isit_a_pkt_epoch(bbr, cts, rsm, __LINE__, BBR_CUM_ACKED); 7658 /* Adjust the packet counts */ 7659 left = th_ack - rsm->r_end; 7660 /* Free back to zone */ 7661 bbr_free(bbr, rsm); 7662 if (left) { 7663 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map); 7664 goto more; 7665 } 7666 goto proc_sack; 7667 } 7668 if (rsm->r_flags & BBR_ACKED) { 7669 /* 7670 * It was acked on the scoreboard -- remove it from total 7671 * for the part being cum-acked. 7672 */ 7673 p_acked += (rsm->r_end - rsm->r_start); 7674 bbr->r_ctl.rc_sacked -= (th_ack - rsm->r_start); 7675 if (bbr->r_ctl.rc_sacked == 0) 7676 bbr->r_ctl.rc_sacklast = NULL; 7677 } else { 7678 /* 7679 * It was acked up to th_ack point for the first time 7680 */ 7681 struct bbr_sendmap lrsm; 7682 7683 memcpy(&lrsm, rsm, sizeof(struct bbr_sendmap)); 7684 lrsm.r_end = th_ack; 7685 bbr_update_rtt(tp, bbr, &lrsm, to, cts, BBR_CUM_ACKED, th_ack); 7686 } 7687 if ((rsm->r_flags & BBR_MARKED_LOST) && 7688 ((rsm->r_flags & BBR_ACKED) == 0)) { 7689 /* 7690 * It was marked lost and partly ack'd now 7691 * for the first time. We lower the rc_lost_bytes 7692 * and still leave it MARKED. 7693 */ 7694 bbr->r_ctl.rc_lost_bytes -= th_ack - rsm->r_start; 7695 } 7696 bbr_isit_a_pkt_epoch(bbr, cts, rsm, __LINE__, BBR_CUM_ACKED); 7697 bbr->r_ctl.rc_holes_rxt -= rsm->r_rtr_bytes; 7698 rsm->r_rtr_bytes = 0; 7699 /* adjust packet count */ 7700 rsm->r_start = th_ack; 7701 proc_sack: 7702 /* Check for reneging */ 7703 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map); 7704 if (rsm && (rsm->r_flags & BBR_ACKED) && (th_ack == rsm->r_start)) { 7705 /* 7706 * The peer has moved snd_una up to the edge of this send, 7707 * i.e. one that it had previously acked. The only way that 7708 * can be true if the peer threw away data (space issues) 7709 * that it had previously sacked (else it would have given 7710 * us snd_una up to (rsm->r_end). We need to undo the acked 7711 * markings here. 7712 * 7713 * Note we have to look to make sure th_ack is our 7714 * rsm->r_start in case we get an old ack where th_ack is 7715 * behind snd_una. 7716 */ 7717 bbr_peer_reneges(bbr, rsm, th->th_ack); 7718 } 7719 if ((to->to_flags & TOF_SACK) == 0) { 7720 /* We are done nothing left to log */ 7721 goto out; 7722 } 7723 rsm = TAILQ_LAST_FAST(&bbr->r_ctl.rc_map, bbr_sendmap, r_next); 7724 if (rsm) { 7725 last_seq = rsm->r_end; 7726 } else { 7727 last_seq = tp->snd_max; 7728 } 7729 /* Sack block processing */ 7730 if (SEQ_GT(th_ack, tp->snd_una)) 7731 ack_point = th_ack; 7732 else 7733 ack_point = tp->snd_una; 7734 for (i = 0; i < to->to_nsacks; i++) { 7735 bcopy((to->to_sacks + i * TCPOLEN_SACK), 7736 &sack, sizeof(sack)); 7737 sack.start = ntohl(sack.start); 7738 sack.end = ntohl(sack.end); 7739 if (SEQ_GT(sack.end, sack.start) && 7740 SEQ_GT(sack.start, ack_point) && 7741 SEQ_LT(sack.start, tp->snd_max) && 7742 SEQ_GT(sack.end, ack_point) && 7743 SEQ_LEQ(sack.end, tp->snd_max)) { 7744 if ((bbr->r_ctl.rc_num_small_maps_alloced > bbr_sack_block_limit) && 7745 (SEQ_LT(sack.end, last_seq)) && 7746 ((sack.end - sack.start) < (p_maxseg / 8))) { 7747 /* 7748 * Not the last piece and its smaller than 7749 * 1/8th of a p_maxseg. We ignore this. 7750 */ 7751 BBR_STAT_INC(bbr_runt_sacks); 7752 continue; 7753 } 7754 sack_blocks[num_sack_blks] = sack; 7755 num_sack_blks++; 7756 #ifdef NETFLIX_STATS 7757 } else if (SEQ_LEQ(sack.start, th_ack) && 7758 SEQ_LEQ(sack.end, th_ack)) { 7759 /* 7760 * Its a D-SACK block. 7761 */ 7762 tcp_record_dsack(sack.start, sack.end); 7763 #endif 7764 } 7765 } 7766 if (num_sack_blks == 0) 7767 goto out; 7768 /* 7769 * Sort the SACK blocks so we can update the rack scoreboard with 7770 * just one pass. 7771 */ 7772 new_sb = sack_filter_blks(&bbr->r_ctl.bbr_sf, sack_blocks, 7773 num_sack_blks, th->th_ack); 7774 ctf_log_sack_filter(bbr->rc_tp, new_sb, sack_blocks); 7775 BBR_STAT_ADD(bbr_sack_blocks, num_sack_blks); 7776 BBR_STAT_ADD(bbr_sack_blocks_skip, (num_sack_blks - new_sb)); 7777 num_sack_blks = new_sb; 7778 if (num_sack_blks < 2) { 7779 goto do_sack_work; 7780 } 7781 /* Sort the sacks */ 7782 for (i = 0; i < num_sack_blks; i++) { 7783 for (j = i + 1; j < num_sack_blks; j++) { 7784 if (SEQ_GT(sack_blocks[i].end, sack_blocks[j].end)) { 7785 sack = sack_blocks[i]; 7786 sack_blocks[i] = sack_blocks[j]; 7787 sack_blocks[j] = sack; 7788 } 7789 } 7790 } 7791 /* 7792 * Now are any of the sack block ends the same (yes some 7793 * implememtations send these)? 7794 */ 7795 again: 7796 if (num_sack_blks > 1) { 7797 for (i = 0; i < num_sack_blks; i++) { 7798 for (j = i + 1; j < num_sack_blks; j++) { 7799 if (sack_blocks[i].end == sack_blocks[j].end) { 7800 /* 7801 * Ok these two have the same end we 7802 * want the smallest end and then 7803 * throw away the larger and start 7804 * again. 7805 */ 7806 if (SEQ_LT(sack_blocks[j].start, sack_blocks[i].start)) { 7807 /* 7808 * The second block covers 7809 * more area use that 7810 */ 7811 sack_blocks[i].start = sack_blocks[j].start; 7812 } 7813 /* 7814 * Now collapse out the dup-sack and 7815 * lower the count 7816 */ 7817 for (k = (j + 1); k < num_sack_blks; k++) { 7818 sack_blocks[j].start = sack_blocks[k].start; 7819 sack_blocks[j].end = sack_blocks[k].end; 7820 j++; 7821 } 7822 num_sack_blks--; 7823 goto again; 7824 } 7825 } 7826 } 7827 } 7828 do_sack_work: 7829 rsm = bbr->r_ctl.rc_sacklast; 7830 for (i = 0; i < num_sack_blks; i++) { 7831 acked = bbr_proc_sack_blk(tp, bbr, &sack_blocks[i], to, &rsm, cts); 7832 if (acked) { 7833 bbr->r_wanted_output = 1; 7834 changed += acked; 7835 sack_changed += acked; 7836 } 7837 } 7838 out: 7839 *prev_acked = p_acked; 7840 if ((sack_changed) && (!IN_RECOVERY(tp->t_flags))) { 7841 /* 7842 * Ok we have a high probability that we need to go in to 7843 * recovery since we have data sack'd 7844 */ 7845 struct bbr_sendmap *rsm; 7846 7847 rsm = bbr_check_recovery_mode(tp, bbr, cts); 7848 if (rsm) { 7849 /* Enter recovery */ 7850 entered_recovery = 1; 7851 bbr->r_wanted_output = 1; 7852 /* 7853 * When we enter recovery we need to assure we send 7854 * one packet. 7855 */ 7856 if (bbr->r_ctl.rc_resend == NULL) { 7857 bbr->r_ctl.rc_resend = rsm; 7858 } 7859 } 7860 } 7861 if (IN_RECOVERY(tp->t_flags) && (entered_recovery == 0)) { 7862 /* 7863 * See if we need to rack-retransmit anything if so set it 7864 * up as the thing to resend assuming something else is not 7865 * already in that position. 7866 */ 7867 if (bbr->r_ctl.rc_resend == NULL) { 7868 bbr->r_ctl.rc_resend = bbr_check_recovery_mode(tp, bbr, cts); 7869 } 7870 } 7871 /* 7872 * We return the amount that changed via sack, this is used by the 7873 * ack-received code to augment what was changed between th_ack <-> 7874 * snd_una. 7875 */ 7876 return (sack_changed); 7877 } 7878 7879 static void 7880 bbr_strike_dupack(struct tcp_bbr *bbr) 7881 { 7882 struct bbr_sendmap *rsm; 7883 7884 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_tmap); 7885 if (rsm && (rsm->r_dupack < 0xff)) { 7886 rsm->r_dupack++; 7887 if (rsm->r_dupack >= DUP_ACK_THRESHOLD) 7888 bbr->r_wanted_output = 1; 7889 } 7890 } 7891 7892 /* 7893 * Return value of 1, we do not need to call bbr_process_data(). 7894 * return value of 0, bbr_process_data can be called. 7895 * For ret_val if its 0 the TCB is locked and valid, if its non-zero 7896 * its unlocked and probably unsafe to touch the TCB. 7897 */ 7898 static int 7899 bbr_process_ack(struct mbuf *m, struct tcphdr *th, struct socket *so, 7900 struct tcpcb *tp, struct tcpopt *to, 7901 uint32_t tiwin, int32_t tlen, 7902 int32_t * ofia, int32_t thflags, int32_t * ret_val) 7903 { 7904 int32_t ourfinisacked = 0; 7905 int32_t acked_amount; 7906 uint16_t nsegs; 7907 int32_t acked; 7908 uint32_t lost, sack_changed = 0; 7909 struct mbuf *mfree; 7910 struct tcp_bbr *bbr; 7911 uint32_t prev_acked = 0; 7912 7913 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 7914 lost = bbr->r_ctl.rc_lost; 7915 nsegs = max(1, m->m_pkthdr.lro_nsegs); 7916 if (SEQ_GT(th->th_ack, tp->snd_max)) { 7917 ctf_do_dropafterack(m, tp, th, thflags, tlen, ret_val); 7918 bbr->r_wanted_output = 1; 7919 return (1); 7920 } 7921 if (SEQ_GEQ(th->th_ack, tp->snd_una) || to->to_nsacks) { 7922 /* Process the ack */ 7923 if (bbr->rc_in_persist) 7924 tp->t_rxtshift = 0; 7925 if ((th->th_ack == tp->snd_una) && (tiwin == tp->snd_wnd)) 7926 bbr_strike_dupack(bbr); 7927 sack_changed = bbr_log_ack(tp, to, th, &prev_acked); 7928 } 7929 bbr_lt_bw_sampling(bbr, bbr->r_ctl.rc_rcvtime, (bbr->r_ctl.rc_lost > lost)); 7930 if (__predict_false(SEQ_LEQ(th->th_ack, tp->snd_una))) { 7931 /* 7932 * Old ack, behind the last one rcv'd or a duplicate ack 7933 * with SACK info. 7934 */ 7935 if (th->th_ack == tp->snd_una) { 7936 bbr_ack_received(tp, bbr, th, 0, sack_changed, prev_acked, __LINE__, 0); 7937 if (bbr->r_state == TCPS_SYN_SENT) { 7938 /* 7939 * Special case on where we sent SYN. When 7940 * the SYN-ACK is processed in syn_sent 7941 * state it bumps the snd_una. This causes 7942 * us to hit here even though we did ack 1 7943 * byte. 7944 * 7945 * Go through the nothing left case so we 7946 * send data. 7947 */ 7948 goto nothing_left; 7949 } 7950 } 7951 return (0); 7952 } 7953 /* 7954 * If we reach this point, ACK is not a duplicate, i.e., it ACKs 7955 * something we sent. 7956 */ 7957 if (tp->t_flags & TF_NEEDSYN) { 7958 /* 7959 * T/TCP: Connection was half-synchronized, and our SYN has 7960 * been ACK'd (so connection is now fully synchronized). Go 7961 * to non-starred state, increment snd_una for ACK of SYN, 7962 * and check if we can do window scaling. 7963 */ 7964 tp->t_flags &= ~TF_NEEDSYN; 7965 tp->snd_una++; 7966 /* Do window scaling? */ 7967 if ((tp->t_flags & (TF_RCVD_SCALE | TF_REQ_SCALE)) == 7968 (TF_RCVD_SCALE | TF_REQ_SCALE)) { 7969 tp->rcv_scale = tp->request_r_scale; 7970 /* Send window already scaled. */ 7971 } 7972 } 7973 INP_WLOCK_ASSERT(tp->t_inpcb); 7974 7975 acked = BYTES_THIS_ACK(tp, th); 7976 TCPSTAT_ADD(tcps_rcvackpack, (int)nsegs); 7977 TCPSTAT_ADD(tcps_rcvackbyte, acked); 7978 7979 /* 7980 * If we just performed our first retransmit, and the ACK arrives 7981 * within our recovery window, then it was a mistake to do the 7982 * retransmit in the first place. Recover our original cwnd and 7983 * ssthresh, and proceed to transmit where we left off. 7984 */ 7985 if (tp->t_flags & TF_PREVVALID) { 7986 tp->t_flags &= ~TF_PREVVALID; 7987 if (tp->t_rxtshift == 1 && 7988 (int)(ticks - tp->t_badrxtwin) < 0) 7989 bbr_cong_signal(tp, th, CC_RTO_ERR, NULL); 7990 } 7991 SOCKBUF_LOCK(&so->so_snd); 7992 acked_amount = min(acked, (int)sbavail(&so->so_snd)); 7993 tp->snd_wnd -= acked_amount; 7994 mfree = sbcut_locked(&so->so_snd, acked_amount); 7995 /* NB: sowwakeup_locked() does an implicit unlock. */ 7996 sowwakeup_locked(so); 7997 m_freem(mfree); 7998 if (SEQ_GT(th->th_ack, tp->snd_una)) { 7999 bbr_collapse_rtt(tp, bbr, TCP_REXMTVAL(tp)); 8000 } 8001 tp->snd_una = th->th_ack; 8002 bbr_ack_received(tp, bbr, th, acked, sack_changed, prev_acked, __LINE__, (bbr->r_ctl.rc_lost - lost)); 8003 if (IN_RECOVERY(tp->t_flags)) { 8004 if (SEQ_LT(th->th_ack, tp->snd_recover) && 8005 (SEQ_LT(th->th_ack, tp->snd_max))) { 8006 tcp_bbr_partialack(tp); 8007 } else { 8008 bbr_post_recovery(tp); 8009 } 8010 } 8011 if (SEQ_GT(tp->snd_una, tp->snd_recover)) { 8012 tp->snd_recover = tp->snd_una; 8013 } 8014 if (SEQ_LT(tp->snd_nxt, tp->snd_max)) { 8015 tp->snd_nxt = tp->snd_max; 8016 } 8017 if (tp->snd_una == tp->snd_max) { 8018 /* Nothing left outstanding */ 8019 nothing_left: 8020 bbr_log_progress_event(bbr, tp, ticks, PROGRESS_CLEAR, __LINE__); 8021 if (sbavail(&tp->t_inpcb->inp_socket->so_snd) == 0) 8022 bbr->rc_tp->t_acktime = 0; 8023 if ((sbused(&so->so_snd) == 0) && 8024 (tp->t_flags & TF_SENTFIN)) { 8025 ourfinisacked = 1; 8026 } 8027 bbr_timer_cancel(bbr, __LINE__, bbr->r_ctl.rc_rcvtime); 8028 if (bbr->rc_in_persist == 0) { 8029 bbr->r_ctl.rc_went_idle_time = bbr->r_ctl.rc_rcvtime; 8030 } 8031 sack_filter_clear(&bbr->r_ctl.bbr_sf, tp->snd_una); 8032 bbr_log_ack_clear(bbr, bbr->r_ctl.rc_rcvtime); 8033 /* 8034 * We invalidate the last ack here since we 8035 * don't want to transfer forward the time 8036 * for our sum's calculations. 8037 */ 8038 if ((tp->t_state >= TCPS_FIN_WAIT_1) && 8039 (sbavail(&so->so_snd) == 0) && 8040 (tp->t_flags2 & TF2_DROP_AF_DATA)) { 8041 /* 8042 * The socket was gone and the peer sent data, time 8043 * to reset him. 8044 */ 8045 *ret_val = 1; 8046 tp = tcp_close(tp); 8047 ctf_do_dropwithreset(m, tp, th, BANDLIM_UNLIMITED, tlen); 8048 BBR_STAT_INC(bbr_dropped_af_data); 8049 return (1); 8050 } 8051 /* Set need output so persist might get set */ 8052 bbr->r_wanted_output = 1; 8053 } 8054 if (ofia) 8055 *ofia = ourfinisacked; 8056 return (0); 8057 } 8058 8059 static void 8060 bbr_enter_persist(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts, int32_t line) 8061 { 8062 if (bbr->rc_in_persist == 0) { 8063 bbr_timer_cancel(bbr, __LINE__, cts); 8064 bbr->r_ctl.rc_last_delay_val = 0; 8065 tp->t_rxtshift = 0; 8066 bbr->rc_in_persist = 1; 8067 bbr->r_ctl.rc_went_idle_time = cts; 8068 /* We should be capped when rw went to 0 but just in case */ 8069 bbr_log_type_pesist(bbr, cts, 0, line, 1); 8070 /* Time freezes for the state, so do the accounting now */ 8071 if (SEQ_GT(cts, bbr->r_ctl.rc_bbr_state_time)) { 8072 uint32_t time_in; 8073 8074 time_in = cts - bbr->r_ctl.rc_bbr_state_time; 8075 if (bbr->rc_bbr_state == BBR_STATE_PROBE_BW) { 8076 int32_t idx; 8077 8078 idx = bbr_state_val(bbr); 8079 counter_u64_add(bbr_state_time[(idx + 5)], time_in); 8080 } else { 8081 counter_u64_add(bbr_state_time[bbr->rc_bbr_state], time_in); 8082 } 8083 } 8084 bbr->r_ctl.rc_bbr_state_time = cts; 8085 } 8086 } 8087 8088 static void 8089 bbr_restart_after_idle(struct tcp_bbr *bbr, uint32_t cts, uint32_t idle_time) 8090 { 8091 /* 8092 * Note that if idle time does not exceed our 8093 * threshold, we do nothing continuing the state 8094 * transitions we were last walking through. 8095 */ 8096 if (idle_time >= bbr_idle_restart_threshold) { 8097 if (bbr->rc_use_idle_restart) { 8098 bbr->rc_bbr_state = BBR_STATE_IDLE_EXIT; 8099 /* 8100 * Set our target using BBR_UNIT, so 8101 * we increase at a dramatic rate but 8102 * we stop when we get the pipe 8103 * full again for our current b/w estimate. 8104 */ 8105 bbr->r_ctl.rc_bbr_hptsi_gain = BBR_UNIT; 8106 bbr->r_ctl.rc_bbr_cwnd_gain = BBR_UNIT; 8107 bbr_set_state_target(bbr, __LINE__); 8108 /* Now setup our gains to ramp up */ 8109 bbr->r_ctl.rc_bbr_hptsi_gain = bbr->r_ctl.rc_startup_pg; 8110 bbr->r_ctl.rc_bbr_cwnd_gain = bbr->r_ctl.rc_startup_pg; 8111 bbr_log_type_statechange(bbr, cts, __LINE__); 8112 } else { 8113 bbr_substate_change(bbr, cts, __LINE__, 1); 8114 } 8115 } 8116 } 8117 8118 static void 8119 bbr_exit_persist(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts, int32_t line) 8120 { 8121 uint32_t idle_time; 8122 8123 if (bbr->rc_in_persist == 0) 8124 return; 8125 idle_time = bbr_calc_time(cts, bbr->r_ctl.rc_went_idle_time); 8126 bbr->rc_in_persist = 0; 8127 bbr->rc_hit_state_1 = 0; 8128 tp->t_flags &= ~TF_FORCEDATA; 8129 bbr->r_ctl.rc_del_time = cts; 8130 /* 8131 * We invalidate the last ack here since we 8132 * don't want to transfer forward the time 8133 * for our sum's calculations. 8134 */ 8135 if (bbr->rc_inp->inp_in_hpts) { 8136 tcp_hpts_remove(bbr->rc_inp, HPTS_REMOVE_OUTPUT); 8137 bbr->rc_timer_first = 0; 8138 bbr->r_ctl.rc_hpts_flags = 0; 8139 bbr->r_ctl.rc_last_delay_val = 0; 8140 bbr->r_ctl.rc_hptsi_agg_delay = 0; 8141 bbr->r_agg_early_set = 0; 8142 bbr->r_ctl.rc_agg_early = 0; 8143 } 8144 bbr_log_type_pesist(bbr, cts, idle_time, line, 0); 8145 if (idle_time >= bbr_rtt_probe_time) { 8146 /* 8147 * This qualifies as a RTT_PROBE session since we drop the 8148 * data outstanding to nothing and waited more than 8149 * bbr_rtt_probe_time. 8150 */ 8151 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_PERSIST, 0); 8152 bbr->r_ctl.last_in_probertt = bbr->r_ctl.rc_rtt_shrinks = cts; 8153 } 8154 tp->t_rxtshift = 0; 8155 /* 8156 * If in probeBW and we have persisted more than an RTT lets do 8157 * special handling. 8158 */ 8159 /* Force a time based epoch */ 8160 bbr_set_epoch(bbr, cts, __LINE__); 8161 /* 8162 * Setup the lost so we don't count anything against the guy 8163 * we have been stuck with during persists. 8164 */ 8165 bbr->r_ctl.bbr_lost_at_state = bbr->r_ctl.rc_lost; 8166 /* Time un-freezes for the state */ 8167 bbr->r_ctl.rc_bbr_state_time = cts; 8168 if ((bbr->rc_bbr_state == BBR_STATE_PROBE_BW) || 8169 (bbr->rc_bbr_state == BBR_STATE_PROBE_RTT)) { 8170 /* 8171 * If we are going back to probe-bw 8172 * or probe_rtt, we may need to possibly 8173 * do a fast restart. 8174 */ 8175 bbr_restart_after_idle(bbr, cts, idle_time); 8176 } 8177 } 8178 8179 static void 8180 bbr_collapsed_window(struct tcp_bbr *bbr) 8181 { 8182 /* 8183 * Now we must walk the 8184 * send map and divide the 8185 * ones left stranded. These 8186 * guys can't cause us to abort 8187 * the connection and are really 8188 * "unsent". However if a buggy 8189 * client actually did keep some 8190 * of the data i.e. collapsed the win 8191 * and refused to ack and then opened 8192 * the win and acked that data. We would 8193 * get into an ack war, the simplier 8194 * method then of just pretending we 8195 * did not send those segments something 8196 * won't work. 8197 */ 8198 struct bbr_sendmap *rsm, *nrsm; 8199 tcp_seq max_seq; 8200 uint32_t maxseg; 8201 int can_split = 0; 8202 int fnd = 0; 8203 8204 maxseg = bbr->rc_tp->t_maxseg - bbr->rc_last_options; 8205 max_seq = bbr->rc_tp->snd_una + bbr->rc_tp->snd_wnd; 8206 bbr_log_type_rwnd_collapse(bbr, max_seq, 1, 0); 8207 TAILQ_FOREACH(rsm, &bbr->r_ctl.rc_map, r_next) { 8208 /* Find the first seq past or at maxseq */ 8209 if (rsm->r_flags & BBR_RWND_COLLAPSED) 8210 rsm->r_flags &= ~BBR_RWND_COLLAPSED; 8211 if (SEQ_GEQ(max_seq, rsm->r_start) && 8212 SEQ_GEQ(rsm->r_end, max_seq)) { 8213 fnd = 1; 8214 break; 8215 } 8216 } 8217 bbr->rc_has_collapsed = 0; 8218 if (!fnd) { 8219 /* Nothing to do strange */ 8220 return; 8221 } 8222 /* 8223 * Now can we split? 8224 * 8225 * We don't want to split if splitting 8226 * would generate too many small segments 8227 * less we let an attacker fragment our 8228 * send_map and leave us out of memory. 8229 */ 8230 if ((max_seq != rsm->r_start) && 8231 (max_seq != rsm->r_end)){ 8232 /* can we split? */ 8233 int res1, res2; 8234 8235 res1 = max_seq - rsm->r_start; 8236 res2 = rsm->r_end - max_seq; 8237 if ((res1 >= (maxseg/8)) && 8238 (res2 >= (maxseg/8))) { 8239 /* No small pieces here */ 8240 can_split = 1; 8241 } else if (bbr->r_ctl.rc_num_small_maps_alloced < bbr_sack_block_limit) { 8242 /* We are under the limit */ 8243 can_split = 1; 8244 } 8245 } 8246 /* Ok do we need to split this rsm? */ 8247 if (max_seq == rsm->r_start) { 8248 /* It's this guy no split required */ 8249 nrsm = rsm; 8250 } else if (max_seq == rsm->r_end) { 8251 /* It's the next one no split required. */ 8252 nrsm = TAILQ_NEXT(rsm, r_next); 8253 if (nrsm == NULL) { 8254 /* Huh? */ 8255 return; 8256 } 8257 } else if (can_split && SEQ_LT(max_seq, rsm->r_end)) { 8258 /* yep we need to split it */ 8259 nrsm = bbr_alloc_limit(bbr, BBR_LIMIT_TYPE_SPLIT); 8260 if (nrsm == NULL) { 8261 /* failed XXXrrs what can we do mark the whole? */ 8262 nrsm = rsm; 8263 goto no_split; 8264 } 8265 /* Clone it */ 8266 bbr_log_type_rwnd_collapse(bbr, max_seq, 3, 0); 8267 bbr_clone_rsm(bbr, nrsm, rsm, max_seq); 8268 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_map, rsm, nrsm, r_next); 8269 if (rsm->r_in_tmap) { 8270 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, rsm, nrsm, r_tnext); 8271 nrsm->r_in_tmap = 1; 8272 } 8273 } else { 8274 /* 8275 * Split not allowed just start here just 8276 * use this guy. 8277 */ 8278 nrsm = rsm; 8279 } 8280 no_split: 8281 BBR_STAT_INC(bbr_collapsed_win); 8282 /* reuse fnd as a count */ 8283 fnd = 0; 8284 TAILQ_FOREACH_FROM(nrsm, &bbr->r_ctl.rc_map, r_next) { 8285 nrsm->r_flags |= BBR_RWND_COLLAPSED; 8286 fnd++; 8287 bbr->rc_has_collapsed = 1; 8288 } 8289 bbr_log_type_rwnd_collapse(bbr, max_seq, 4, fnd); 8290 } 8291 8292 static void 8293 bbr_un_collapse_window(struct tcp_bbr *bbr) 8294 { 8295 struct bbr_sendmap *rsm; 8296 int cleared = 0; 8297 8298 TAILQ_FOREACH_REVERSE(rsm, &bbr->r_ctl.rc_map, bbr_head, r_next) { 8299 if (rsm->r_flags & BBR_RWND_COLLAPSED) { 8300 /* Clear the flag */ 8301 rsm->r_flags &= ~BBR_RWND_COLLAPSED; 8302 cleared++; 8303 } else 8304 break; 8305 } 8306 bbr_log_type_rwnd_collapse(bbr, 8307 (bbr->rc_tp->snd_una + bbr->rc_tp->snd_wnd), 0, cleared); 8308 bbr->rc_has_collapsed = 0; 8309 } 8310 8311 /* 8312 * Return value of 1, the TCB is unlocked and most 8313 * likely gone, return value of 0, the TCB is still 8314 * locked. 8315 */ 8316 static int 8317 bbr_process_data(struct mbuf *m, struct tcphdr *th, struct socket *so, 8318 struct tcpcb *tp, int32_t drop_hdrlen, int32_t tlen, 8319 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt) 8320 { 8321 /* 8322 * Update window information. Don't look at window if no ACK: TAC's 8323 * send garbage on first SYN. 8324 */ 8325 uint16_t nsegs; 8326 int32_t tfo_syn; 8327 struct tcp_bbr *bbr; 8328 8329 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 8330 INP_WLOCK_ASSERT(tp->t_inpcb); 8331 nsegs = max(1, m->m_pkthdr.lro_nsegs); 8332 if ((thflags & TH_ACK) && 8333 (SEQ_LT(tp->snd_wl1, th->th_seq) || 8334 (tp->snd_wl1 == th->th_seq && (SEQ_LT(tp->snd_wl2, th->th_ack) || 8335 (tp->snd_wl2 == th->th_ack && tiwin > tp->snd_wnd))))) { 8336 /* keep track of pure window updates */ 8337 if (tlen == 0 && 8338 tp->snd_wl2 == th->th_ack && tiwin > tp->snd_wnd) 8339 TCPSTAT_INC(tcps_rcvwinupd); 8340 tp->snd_wnd = tiwin; 8341 tp->snd_wl1 = th->th_seq; 8342 tp->snd_wl2 = th->th_ack; 8343 if (tp->snd_wnd > tp->max_sndwnd) 8344 tp->max_sndwnd = tp->snd_wnd; 8345 bbr->r_wanted_output = 1; 8346 } else if (thflags & TH_ACK) { 8347 if ((tp->snd_wl2 == th->th_ack) && (tiwin < tp->snd_wnd)) { 8348 tp->snd_wnd = tiwin; 8349 tp->snd_wl1 = th->th_seq; 8350 tp->snd_wl2 = th->th_ack; 8351 } 8352 } 8353 if (tp->snd_wnd < ctf_outstanding(tp)) 8354 /* The peer collapsed its window on us */ 8355 bbr_collapsed_window(bbr); 8356 else if (bbr->rc_has_collapsed) 8357 bbr_un_collapse_window(bbr); 8358 /* Was persist timer active and now we have window space? */ 8359 if ((bbr->rc_in_persist != 0) && 8360 (tp->snd_wnd >= min((bbr->r_ctl.rc_high_rwnd/2), 8361 bbr_minseg(bbr)))) { 8362 /* 8363 * Make the rate persist at end of persist mode if idle long 8364 * enough 8365 */ 8366 bbr_exit_persist(tp, bbr, bbr->r_ctl.rc_rcvtime, __LINE__); 8367 8368 /* Make sure we output to start the timer */ 8369 bbr->r_wanted_output = 1; 8370 } 8371 /* Do we need to enter persist? */ 8372 if ((bbr->rc_in_persist == 0) && 8373 (tp->snd_wnd < min((bbr->r_ctl.rc_high_rwnd/2), bbr_minseg(bbr))) && 8374 TCPS_HAVEESTABLISHED(tp->t_state) && 8375 (tp->snd_max == tp->snd_una) && 8376 sbavail(&tp->t_inpcb->inp_socket->so_snd) && 8377 (sbavail(&tp->t_inpcb->inp_socket->so_snd) > tp->snd_wnd)) { 8378 /* No send window.. we must enter persist */ 8379 bbr_enter_persist(tp, bbr, bbr->r_ctl.rc_rcvtime, __LINE__); 8380 } 8381 if (tp->t_flags2 & TF2_DROP_AF_DATA) { 8382 m_freem(m); 8383 return (0); 8384 } 8385 /* 8386 * Process segments with URG. 8387 */ 8388 if ((thflags & TH_URG) && th->th_urp && 8389 TCPS_HAVERCVDFIN(tp->t_state) == 0) { 8390 /* 8391 * This is a kludge, but if we receive and accept random 8392 * urgent pointers, we'll crash in soreceive. It's hard to 8393 * imagine someone actually wanting to send this much urgent 8394 * data. 8395 */ 8396 SOCKBUF_LOCK(&so->so_rcv); 8397 if (th->th_urp + sbavail(&so->so_rcv) > sb_max) { 8398 th->th_urp = 0; /* XXX */ 8399 thflags &= ~TH_URG; /* XXX */ 8400 SOCKBUF_UNLOCK(&so->so_rcv); /* XXX */ 8401 goto dodata; /* XXX */ 8402 } 8403 /* 8404 * If this segment advances the known urgent pointer, then 8405 * mark the data stream. This should not happen in 8406 * CLOSE_WAIT, CLOSING, LAST_ACK or TIME_WAIT STATES since a 8407 * FIN has been received from the remote side. In these 8408 * states we ignore the URG. 8409 * 8410 * According to RFC961 (Assigned Protocols), the urgent 8411 * pointer points to the last octet of urgent data. We 8412 * continue, however, to consider it to indicate the first 8413 * octet of data past the urgent section as the original 8414 * spec states (in one of two places). 8415 */ 8416 if (SEQ_GT(th->th_seq + th->th_urp, tp->rcv_up)) { 8417 tp->rcv_up = th->th_seq + th->th_urp; 8418 so->so_oobmark = sbavail(&so->so_rcv) + 8419 (tp->rcv_up - tp->rcv_nxt) - 1; 8420 if (so->so_oobmark == 0) 8421 so->so_rcv.sb_state |= SBS_RCVATMARK; 8422 sohasoutofband(so); 8423 tp->t_oobflags &= ~(TCPOOB_HAVEDATA | TCPOOB_HADDATA); 8424 } 8425 SOCKBUF_UNLOCK(&so->so_rcv); 8426 /* 8427 * Remove out of band data so doesn't get presented to user. 8428 * This can happen independent of advancing the URG pointer, 8429 * but if two URG's are pending at once, some out-of-band 8430 * data may creep in... ick. 8431 */ 8432 if (th->th_urp <= (uint32_t)tlen && 8433 !(so->so_options & SO_OOBINLINE)) { 8434 /* hdr drop is delayed */ 8435 tcp_pulloutofband(so, th, m, drop_hdrlen); 8436 } 8437 } else { 8438 /* 8439 * If no out of band data is expected, pull receive urgent 8440 * pointer along with the receive window. 8441 */ 8442 if (SEQ_GT(tp->rcv_nxt, tp->rcv_up)) 8443 tp->rcv_up = tp->rcv_nxt; 8444 } 8445 dodata: /* XXX */ 8446 INP_WLOCK_ASSERT(tp->t_inpcb); 8447 8448 /* 8449 * Process the segment text, merging it into the TCP sequencing 8450 * queue, and arranging for acknowledgment of receipt if necessary. 8451 * This process logically involves adjusting tp->rcv_wnd as data is 8452 * presented to the user (this happens in tcp_usrreq.c, case 8453 * PRU_RCVD). If a FIN has already been received on this connection 8454 * then we just ignore the text. 8455 */ 8456 tfo_syn = ((tp->t_state == TCPS_SYN_RECEIVED) && 8457 IS_FASTOPEN(tp->t_flags)); 8458 if ((tlen || (thflags & TH_FIN) || tfo_syn) && 8459 TCPS_HAVERCVDFIN(tp->t_state) == 0) { 8460 tcp_seq save_start = th->th_seq; 8461 tcp_seq save_rnxt = tp->rcv_nxt; 8462 int save_tlen = tlen; 8463 8464 m_adj(m, drop_hdrlen); /* delayed header drop */ 8465 /* 8466 * Insert segment which includes th into TCP reassembly 8467 * queue with control block tp. Set thflags to whether 8468 * reassembly now includes a segment with FIN. This handles 8469 * the common case inline (segment is the next to be 8470 * received on an established connection, and the queue is 8471 * empty), avoiding linkage into and removal from the queue 8472 * and repetition of various conversions. Set DELACK for 8473 * segments received in order, but ack immediately when 8474 * segments are out of order (so fast retransmit can work). 8475 */ 8476 if (th->th_seq == tp->rcv_nxt && 8477 SEGQ_EMPTY(tp) && 8478 (TCPS_HAVEESTABLISHED(tp->t_state) || 8479 tfo_syn)) { 8480 #ifdef NETFLIX_SB_LIMITS 8481 u_int mcnt, appended; 8482 8483 if (so->so_rcv.sb_shlim) { 8484 mcnt = m_memcnt(m); 8485 appended = 0; 8486 if (counter_fo_get(so->so_rcv.sb_shlim, mcnt, 8487 CFO_NOSLEEP, NULL) == false) { 8488 counter_u64_add(tcp_sb_shlim_fails, 1); 8489 m_freem(m); 8490 return (0); 8491 } 8492 } 8493 #endif 8494 if (DELAY_ACK(tp, bbr, nsegs) || tfo_syn) { 8495 bbr->bbr_segs_rcvd += max(1, nsegs); 8496 tp->t_flags |= TF_DELACK; 8497 bbr_timer_cancel(bbr, __LINE__, bbr->r_ctl.rc_rcvtime); 8498 } else { 8499 bbr->r_wanted_output = 1; 8500 tp->t_flags |= TF_ACKNOW; 8501 } 8502 tp->rcv_nxt += tlen; 8503 thflags = th->th_flags & TH_FIN; 8504 TCPSTAT_ADD(tcps_rcvpack, (int)nsegs); 8505 TCPSTAT_ADD(tcps_rcvbyte, tlen); 8506 SOCKBUF_LOCK(&so->so_rcv); 8507 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) 8508 m_freem(m); 8509 else 8510 #ifdef NETFLIX_SB_LIMITS 8511 appended = 8512 #endif 8513 sbappendstream_locked(&so->so_rcv, m, 0); 8514 /* NB: sorwakeup_locked() does an implicit unlock. */ 8515 sorwakeup_locked(so); 8516 #ifdef NETFLIX_SB_LIMITS 8517 if (so->so_rcv.sb_shlim && appended != mcnt) 8518 counter_fo_release(so->so_rcv.sb_shlim, 8519 mcnt - appended); 8520 #endif 8521 } else { 8522 /* 8523 * XXX: Due to the header drop above "th" is 8524 * theoretically invalid by now. Fortunately 8525 * m_adj() doesn't actually frees any mbufs when 8526 * trimming from the head. 8527 */ 8528 tcp_seq temp = save_start; 8529 thflags = tcp_reass(tp, th, &temp, &tlen, m); 8530 tp->t_flags |= TF_ACKNOW; 8531 } 8532 if ((tp->t_flags & TF_SACK_PERMIT) && (save_tlen > 0)) { 8533 if ((tlen == 0) && (SEQ_LT(save_start, save_rnxt))) { 8534 /* 8535 * DSACK actually handled in the fastpath 8536 * above. 8537 */ 8538 tcp_update_sack_list(tp, save_start, 8539 save_start + save_tlen); 8540 } else if ((tlen > 0) && SEQ_GT(tp->rcv_nxt, save_rnxt)) { 8541 if ((tp->rcv_numsacks >= 1) && 8542 (tp->sackblks[0].end == save_start)) { 8543 /* 8544 * Partial overlap, recorded at todrop 8545 * above. 8546 */ 8547 tcp_update_sack_list(tp, 8548 tp->sackblks[0].start, 8549 tp->sackblks[0].end); 8550 } else { 8551 tcp_update_dsack_list(tp, save_start, 8552 save_start + save_tlen); 8553 } 8554 } else if (tlen >= save_tlen) { 8555 /* Update of sackblks. */ 8556 tcp_update_dsack_list(tp, save_start, 8557 save_start + save_tlen); 8558 } else if (tlen > 0) { 8559 tcp_update_dsack_list(tp, save_start, 8560 save_start + tlen); 8561 } 8562 } 8563 } else { 8564 m_freem(m); 8565 thflags &= ~TH_FIN; 8566 } 8567 8568 /* 8569 * If FIN is received ACK the FIN and let the user know that the 8570 * connection is closing. 8571 */ 8572 if (thflags & TH_FIN) { 8573 if (TCPS_HAVERCVDFIN(tp->t_state) == 0) { 8574 socantrcvmore(so); 8575 /* 8576 * If connection is half-synchronized (ie NEEDSYN 8577 * flag on) then delay ACK, so it may be piggybacked 8578 * when SYN is sent. Otherwise, since we received a 8579 * FIN then no more input can be expected, send ACK 8580 * now. 8581 */ 8582 if (tp->t_flags & TF_NEEDSYN) { 8583 tp->t_flags |= TF_DELACK; 8584 bbr_timer_cancel(bbr, 8585 __LINE__, bbr->r_ctl.rc_rcvtime); 8586 } else { 8587 tp->t_flags |= TF_ACKNOW; 8588 } 8589 tp->rcv_nxt++; 8590 } 8591 switch (tp->t_state) { 8592 8593 /* 8594 * In SYN_RECEIVED and ESTABLISHED STATES enter the 8595 * CLOSE_WAIT state. 8596 */ 8597 case TCPS_SYN_RECEIVED: 8598 tp->t_starttime = ticks; 8599 /* FALLTHROUGH */ 8600 case TCPS_ESTABLISHED: 8601 tcp_state_change(tp, TCPS_CLOSE_WAIT); 8602 break; 8603 8604 /* 8605 * If still in FIN_WAIT_1 STATE FIN has not been 8606 * acked so enter the CLOSING state. 8607 */ 8608 case TCPS_FIN_WAIT_1: 8609 tcp_state_change(tp, TCPS_CLOSING); 8610 break; 8611 8612 /* 8613 * In FIN_WAIT_2 state enter the TIME_WAIT state, 8614 * starting the time-wait timer, turning off the 8615 * other standard timers. 8616 */ 8617 case TCPS_FIN_WAIT_2: 8618 bbr->rc_timer_first = 1; 8619 bbr_timer_cancel(bbr, 8620 __LINE__, bbr->r_ctl.rc_rcvtime); 8621 INP_WLOCK_ASSERT(tp->t_inpcb); 8622 tcp_twstart(tp); 8623 return (1); 8624 } 8625 } 8626 /* 8627 * Return any desired output. 8628 */ 8629 if ((tp->t_flags & TF_ACKNOW) || 8630 (sbavail(&so->so_snd) > ctf_outstanding(tp))) { 8631 bbr->r_wanted_output = 1; 8632 } 8633 INP_WLOCK_ASSERT(tp->t_inpcb); 8634 return (0); 8635 } 8636 8637 /* 8638 * Here nothing is really faster, its just that we 8639 * have broken out the fast-data path also just like 8640 * the fast-ack. Return 1 if we processed the packet 8641 * return 0 if you need to take the "slow-path". 8642 */ 8643 static int 8644 bbr_do_fastnewdata(struct mbuf *m, struct tcphdr *th, struct socket *so, 8645 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, 8646 uint32_t tiwin, int32_t nxt_pkt) 8647 { 8648 uint16_t nsegs; 8649 int32_t newsize = 0; /* automatic sockbuf scaling */ 8650 struct tcp_bbr *bbr; 8651 #ifdef NETFLIX_SB_LIMITS 8652 u_int mcnt, appended; 8653 #endif 8654 #ifdef TCPDEBUG 8655 /* 8656 * The size of tcp_saveipgen must be the size of the max ip header, 8657 * now IPv6. 8658 */ 8659 u_char tcp_saveipgen[IP6_HDR_LEN]; 8660 struct tcphdr tcp_savetcp; 8661 short ostate = 0; 8662 8663 #endif 8664 /* On the hpts and we would have called output */ 8665 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 8666 8667 /* 8668 * If last ACK falls within this segment's sequence numbers, record 8669 * the timestamp. NOTE that the test is modified according to the 8670 * latest proposal of the tcplw@cray.com list (Braden 1993/04/26). 8671 */ 8672 if (bbr->r_ctl.rc_resend != NULL) { 8673 return (0); 8674 } 8675 if (tiwin && tiwin != tp->snd_wnd) { 8676 return (0); 8677 } 8678 if (__predict_false((tp->t_flags & (TF_NEEDSYN | TF_NEEDFIN)))) { 8679 return (0); 8680 } 8681 if (__predict_false((to->to_flags & TOF_TS) && 8682 (TSTMP_LT(to->to_tsval, tp->ts_recent)))) { 8683 return (0); 8684 } 8685 if (__predict_false((th->th_ack != tp->snd_una))) { 8686 return (0); 8687 } 8688 if (__predict_false(tlen > sbspace(&so->so_rcv))) { 8689 return (0); 8690 } 8691 if ((to->to_flags & TOF_TS) != 0 && 8692 SEQ_LEQ(th->th_seq, tp->last_ack_sent)) { 8693 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv); 8694 tp->ts_recent = to->to_tsval; 8695 } 8696 /* 8697 * This is a pure, in-sequence data packet with nothing on the 8698 * reassembly queue and we have enough buffer space to take it. 8699 */ 8700 nsegs = max(1, m->m_pkthdr.lro_nsegs); 8701 #ifdef NETFLIX_SB_LIMITS 8702 if (so->so_rcv.sb_shlim) { 8703 mcnt = m_memcnt(m); 8704 appended = 0; 8705 if (counter_fo_get(so->so_rcv.sb_shlim, mcnt, 8706 CFO_NOSLEEP, NULL) == false) { 8707 counter_u64_add(tcp_sb_shlim_fails, 1); 8708 m_freem(m); 8709 return (1); 8710 } 8711 } 8712 #endif 8713 /* Clean receiver SACK report if present */ 8714 if (tp->rcv_numsacks) 8715 tcp_clean_sackreport(tp); 8716 TCPSTAT_INC(tcps_preddat); 8717 tp->rcv_nxt += tlen; 8718 /* 8719 * Pull snd_wl1 up to prevent seq wrap relative to th_seq. 8720 */ 8721 tp->snd_wl1 = th->th_seq; 8722 /* 8723 * Pull rcv_up up to prevent seq wrap relative to rcv_nxt. 8724 */ 8725 tp->rcv_up = tp->rcv_nxt; 8726 TCPSTAT_ADD(tcps_rcvpack, (int)nsegs); 8727 TCPSTAT_ADD(tcps_rcvbyte, tlen); 8728 #ifdef TCPDEBUG 8729 if (so->so_options & SO_DEBUG) 8730 tcp_trace(TA_INPUT, ostate, tp, 8731 (void *)tcp_saveipgen, &tcp_savetcp, 0); 8732 #endif 8733 newsize = tcp_autorcvbuf(m, th, so, tp, tlen); 8734 8735 /* Add data to socket buffer. */ 8736 SOCKBUF_LOCK(&so->so_rcv); 8737 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { 8738 m_freem(m); 8739 } else { 8740 /* 8741 * Set new socket buffer size. Give up when limit is 8742 * reached. 8743 */ 8744 if (newsize) 8745 if (!sbreserve_locked(&so->so_rcv, 8746 newsize, so, NULL)) 8747 so->so_rcv.sb_flags &= ~SB_AUTOSIZE; 8748 m_adj(m, drop_hdrlen); /* delayed header drop */ 8749 #ifdef NETFLIX_SB_LIMITS 8750 appended = 8751 #endif 8752 sbappendstream_locked(&so->so_rcv, m, 0); 8753 ctf_calc_rwin(so, tp); 8754 } 8755 /* NB: sorwakeup_locked() does an implicit unlock. */ 8756 sorwakeup_locked(so); 8757 #ifdef NETFLIX_SB_LIMITS 8758 if (so->so_rcv.sb_shlim && mcnt != appended) 8759 counter_fo_release(so->so_rcv.sb_shlim, mcnt - appended); 8760 #endif 8761 if (DELAY_ACK(tp, bbr, nsegs)) { 8762 bbr->bbr_segs_rcvd += max(1, nsegs); 8763 tp->t_flags |= TF_DELACK; 8764 bbr_timer_cancel(bbr, __LINE__, bbr->r_ctl.rc_rcvtime); 8765 } else { 8766 bbr->r_wanted_output = 1; 8767 tp->t_flags |= TF_ACKNOW; 8768 } 8769 return (1); 8770 } 8771 8772 /* 8773 * This subfunction is used to try to highly optimize the 8774 * fast path. We again allow window updates that are 8775 * in sequence to remain in the fast-path. We also add 8776 * in the __predict's to attempt to help the compiler. 8777 * Note that if we return a 0, then we can *not* process 8778 * it and the caller should push the packet into the 8779 * slow-path. If we return 1, then all is well and 8780 * the packet is fully processed. 8781 */ 8782 static int 8783 bbr_fastack(struct mbuf *m, struct tcphdr *th, struct socket *so, 8784 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, 8785 uint32_t tiwin, int32_t nxt_pkt) 8786 { 8787 int32_t acked; 8788 uint16_t nsegs; 8789 uint32_t sack_changed; 8790 #ifdef TCPDEBUG 8791 /* 8792 * The size of tcp_saveipgen must be the size of the max ip header, 8793 * now IPv6. 8794 */ 8795 u_char tcp_saveipgen[IP6_HDR_LEN]; 8796 struct tcphdr tcp_savetcp; 8797 short ostate = 0; 8798 8799 #endif 8800 uint32_t prev_acked = 0; 8801 struct tcp_bbr *bbr; 8802 8803 if (__predict_false(SEQ_LEQ(th->th_ack, tp->snd_una))) { 8804 /* Old ack, behind (or duplicate to) the last one rcv'd */ 8805 return (0); 8806 } 8807 if (__predict_false(SEQ_GT(th->th_ack, tp->snd_max))) { 8808 /* Above what we have sent? */ 8809 return (0); 8810 } 8811 if (__predict_false(tiwin == 0)) { 8812 /* zero window */ 8813 return (0); 8814 } 8815 if (__predict_false(tp->t_flags & (TF_NEEDSYN | TF_NEEDFIN))) { 8816 /* We need a SYN or a FIN, unlikely.. */ 8817 return (0); 8818 } 8819 if ((to->to_flags & TOF_TS) && __predict_false(TSTMP_LT(to->to_tsval, tp->ts_recent))) { 8820 /* Timestamp is behind .. old ack with seq wrap? */ 8821 return (0); 8822 } 8823 if (__predict_false(IN_RECOVERY(tp->t_flags))) { 8824 /* Still recovering */ 8825 return (0); 8826 } 8827 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 8828 if (__predict_false(bbr->r_ctl.rc_resend != NULL)) { 8829 /* We are retransmitting */ 8830 return (0); 8831 } 8832 if (__predict_false(bbr->rc_in_persist != 0)) { 8833 /* In persist mode */ 8834 return (0); 8835 } 8836 if (bbr->r_ctl.rc_sacked) { 8837 /* We have sack holes on our scoreboard */ 8838 return (0); 8839 } 8840 /* Ok if we reach here, we can process a fast-ack */ 8841 nsegs = max(1, m->m_pkthdr.lro_nsegs); 8842 sack_changed = bbr_log_ack(tp, to, th, &prev_acked); 8843 /* 8844 * We never detect loss in fast ack [we can't 8845 * have a sack and can't be in recovery so 8846 * we always pass 0 (nothing detected)]. 8847 */ 8848 bbr_lt_bw_sampling(bbr, bbr->r_ctl.rc_rcvtime, 0); 8849 /* Did the window get updated? */ 8850 if (tiwin != tp->snd_wnd) { 8851 tp->snd_wnd = tiwin; 8852 tp->snd_wl1 = th->th_seq; 8853 if (tp->snd_wnd > tp->max_sndwnd) 8854 tp->max_sndwnd = tp->snd_wnd; 8855 } 8856 /* Do we need to exit persists? */ 8857 if ((bbr->rc_in_persist != 0) && 8858 (tp->snd_wnd >= min((bbr->r_ctl.rc_high_rwnd/2), 8859 bbr_minseg(bbr)))) { 8860 bbr_exit_persist(tp, bbr, bbr->r_ctl.rc_rcvtime, __LINE__); 8861 bbr->r_wanted_output = 1; 8862 } 8863 /* Do we need to enter persists? */ 8864 if ((bbr->rc_in_persist == 0) && 8865 (tp->snd_wnd < min((bbr->r_ctl.rc_high_rwnd/2), bbr_minseg(bbr))) && 8866 TCPS_HAVEESTABLISHED(tp->t_state) && 8867 (tp->snd_max == tp->snd_una) && 8868 sbavail(&tp->t_inpcb->inp_socket->so_snd) && 8869 (sbavail(&tp->t_inpcb->inp_socket->so_snd) > tp->snd_wnd)) { 8870 /* No send window.. we must enter persist */ 8871 bbr_enter_persist(tp, bbr, bbr->r_ctl.rc_rcvtime, __LINE__); 8872 } 8873 /* 8874 * If last ACK falls within this segment's sequence numbers, record 8875 * the timestamp. NOTE that the test is modified according to the 8876 * latest proposal of the tcplw@cray.com list (Braden 1993/04/26). 8877 */ 8878 if ((to->to_flags & TOF_TS) != 0 && 8879 SEQ_LEQ(th->th_seq, tp->last_ack_sent)) { 8880 tp->ts_recent_age = bbr->r_ctl.rc_rcvtime; 8881 tp->ts_recent = to->to_tsval; 8882 } 8883 /* 8884 * This is a pure ack for outstanding data. 8885 */ 8886 TCPSTAT_INC(tcps_predack); 8887 8888 /* 8889 * "bad retransmit" recovery. 8890 */ 8891 if (tp->t_flags & TF_PREVVALID) { 8892 tp->t_flags &= ~TF_PREVVALID; 8893 if (tp->t_rxtshift == 1 && 8894 (int)(ticks - tp->t_badrxtwin) < 0) 8895 bbr_cong_signal(tp, th, CC_RTO_ERR, NULL); 8896 } 8897 /* 8898 * Recalculate the transmit timer / rtt. 8899 * 8900 * Some boxes send broken timestamp replies during the SYN+ACK 8901 * phase, ignore timestamps of 0 or we could calculate a huge RTT 8902 * and blow up the retransmit timer. 8903 */ 8904 acked = BYTES_THIS_ACK(tp, th); 8905 8906 #ifdef TCP_HHOOK 8907 /* Run HHOOK_TCP_ESTABLISHED_IN helper hooks. */ 8908 hhook_run_tcp_est_in(tp, th, to); 8909 #endif 8910 8911 TCPSTAT_ADD(tcps_rcvackpack, (int)nsegs); 8912 TCPSTAT_ADD(tcps_rcvackbyte, acked); 8913 sbdrop(&so->so_snd, acked); 8914 8915 if (SEQ_GT(th->th_ack, tp->snd_una)) 8916 bbr_collapse_rtt(tp, bbr, TCP_REXMTVAL(tp)); 8917 tp->snd_una = th->th_ack; 8918 if (tp->snd_wnd < ctf_outstanding(tp)) 8919 /* The peer collapsed its window on us */ 8920 bbr_collapsed_window(bbr); 8921 else if (bbr->rc_has_collapsed) 8922 bbr_un_collapse_window(bbr); 8923 8924 if (SEQ_GT(tp->snd_una, tp->snd_recover)) { 8925 tp->snd_recover = tp->snd_una; 8926 } 8927 bbr_ack_received(tp, bbr, th, acked, sack_changed, prev_acked, __LINE__, 0); 8928 /* 8929 * Pull snd_wl2 up to prevent seq wrap relative to th_ack. 8930 */ 8931 tp->snd_wl2 = th->th_ack; 8932 m_freem(m); 8933 /* 8934 * If all outstanding data are acked, stop retransmit timer, 8935 * otherwise restart timer using current (possibly backed-off) 8936 * value. If process is waiting for space, wakeup/selwakeup/signal. 8937 * If data are ready to send, let tcp_output decide between more 8938 * output or persist. 8939 */ 8940 #ifdef TCPDEBUG 8941 if (so->so_options & SO_DEBUG) 8942 tcp_trace(TA_INPUT, ostate, tp, 8943 (void *)tcp_saveipgen, 8944 &tcp_savetcp, 0); 8945 #endif 8946 /* Wake up the socket if we have room to write more */ 8947 sowwakeup(so); 8948 if (tp->snd_una == tp->snd_max) { 8949 /* Nothing left outstanding */ 8950 bbr_log_progress_event(bbr, tp, ticks, PROGRESS_CLEAR, __LINE__); 8951 if (sbavail(&tp->t_inpcb->inp_socket->so_snd) == 0) 8952 bbr->rc_tp->t_acktime = 0; 8953 bbr_timer_cancel(bbr, __LINE__, bbr->r_ctl.rc_rcvtime); 8954 if (bbr->rc_in_persist == 0) { 8955 bbr->r_ctl.rc_went_idle_time = bbr->r_ctl.rc_rcvtime; 8956 } 8957 sack_filter_clear(&bbr->r_ctl.bbr_sf, tp->snd_una); 8958 bbr_log_ack_clear(bbr, bbr->r_ctl.rc_rcvtime); 8959 /* 8960 * We invalidate the last ack here since we 8961 * don't want to transfer forward the time 8962 * for our sum's calculations. 8963 */ 8964 bbr->r_wanted_output = 1; 8965 } 8966 if (sbavail(&so->so_snd)) { 8967 bbr->r_wanted_output = 1; 8968 } 8969 return (1); 8970 } 8971 8972 /* 8973 * Return value of 1, the TCB is unlocked and most 8974 * likely gone, return value of 0, the TCB is still 8975 * locked. 8976 */ 8977 static int 8978 bbr_do_syn_sent(struct mbuf *m, struct tcphdr *th, struct socket *so, 8979 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, 8980 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt) 8981 { 8982 int32_t todrop; 8983 int32_t ourfinisacked = 0; 8984 struct tcp_bbr *bbr; 8985 int32_t ret_val = 0; 8986 8987 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 8988 ctf_calc_rwin(so, tp); 8989 /* 8990 * If the state is SYN_SENT: if seg contains an ACK, but not for our 8991 * SYN, drop the input. if seg contains a RST, then drop the 8992 * connection. if seg does not contain SYN, then drop it. Otherwise 8993 * this is an acceptable SYN segment initialize tp->rcv_nxt and 8994 * tp->irs if seg contains ack then advance tp->snd_una. BRR does 8995 * not support ECN so we will not say we are capable. if SYN has 8996 * been acked change to ESTABLISHED else SYN_RCVD state arrange for 8997 * segment to be acked (eventually) continue processing rest of 8998 * data/controls, beginning with URG 8999 */ 9000 if ((thflags & TH_ACK) && 9001 (SEQ_LEQ(th->th_ack, tp->iss) || 9002 SEQ_GT(th->th_ack, tp->snd_max))) { 9003 ctf_do_dropwithreset(m, tp, th, BANDLIM_RST_OPENPORT, tlen); 9004 return (1); 9005 } 9006 if ((thflags & (TH_ACK | TH_RST)) == (TH_ACK | TH_RST)) { 9007 TCP_PROBE5(connect__refused, NULL, tp, 9008 mtod(m, const char *), tp, th); 9009 tp = tcp_drop(tp, ECONNREFUSED); 9010 ctf_do_drop(m, tp); 9011 return (1); 9012 } 9013 if (thflags & TH_RST) { 9014 ctf_do_drop(m, tp); 9015 return (1); 9016 } 9017 if (!(thflags & TH_SYN)) { 9018 ctf_do_drop(m, tp); 9019 return (1); 9020 } 9021 tp->irs = th->th_seq; 9022 tcp_rcvseqinit(tp); 9023 if (thflags & TH_ACK) { 9024 int tfo_partial = 0; 9025 9026 TCPSTAT_INC(tcps_connects); 9027 soisconnected(so); 9028 #ifdef MAC 9029 mac_socketpeer_set_from_mbuf(m, so); 9030 #endif 9031 /* Do window scaling on this connection? */ 9032 if ((tp->t_flags & (TF_RCVD_SCALE | TF_REQ_SCALE)) == 9033 (TF_RCVD_SCALE | TF_REQ_SCALE)) { 9034 tp->rcv_scale = tp->request_r_scale; 9035 } 9036 tp->rcv_adv += min(tp->rcv_wnd, 9037 TCP_MAXWIN << tp->rcv_scale); 9038 /* 9039 * If not all the data that was sent in the TFO SYN 9040 * has been acked, resend the remainder right away. 9041 */ 9042 if (IS_FASTOPEN(tp->t_flags) && 9043 (tp->snd_una != tp->snd_max)) { 9044 tp->snd_nxt = th->th_ack; 9045 tfo_partial = 1; 9046 } 9047 /* 9048 * If there's data, delay ACK; if there's also a FIN ACKNOW 9049 * will be turned on later. 9050 */ 9051 if (DELAY_ACK(tp, bbr, 1) && tlen != 0 && (tfo_partial == 0)) { 9052 bbr->bbr_segs_rcvd += 1; 9053 tp->t_flags |= TF_DELACK; 9054 bbr_timer_cancel(bbr, __LINE__, bbr->r_ctl.rc_rcvtime); 9055 } else { 9056 bbr->r_wanted_output = 1; 9057 tp->t_flags |= TF_ACKNOW; 9058 } 9059 if (SEQ_GT(th->th_ack, tp->iss)) { 9060 /* 9061 * The SYN is acked 9062 * handle it specially. 9063 */ 9064 bbr_log_syn(tp, to); 9065 } 9066 if (SEQ_GT(th->th_ack, tp->snd_una)) { 9067 /* 9068 * We advance snd_una for the 9069 * fast open case. If th_ack is 9070 * acknowledging data beyond 9071 * snd_una we can't just call 9072 * ack-processing since the 9073 * data stream in our send-map 9074 * will start at snd_una + 1 (one 9075 * beyond the SYN). If its just 9076 * equal we don't need to do that 9077 * and there is no send_map. 9078 */ 9079 tp->snd_una++; 9080 } 9081 /* 9082 * Received <SYN,ACK> in SYN_SENT[*] state. Transitions: 9083 * SYN_SENT --> ESTABLISHED SYN_SENT* --> FIN_WAIT_1 9084 */ 9085 tp->t_starttime = ticks; 9086 if (tp->t_flags & TF_NEEDFIN) { 9087 tcp_state_change(tp, TCPS_FIN_WAIT_1); 9088 tp->t_flags &= ~TF_NEEDFIN; 9089 thflags &= ~TH_SYN; 9090 } else { 9091 tcp_state_change(tp, TCPS_ESTABLISHED); 9092 TCP_PROBE5(connect__established, NULL, tp, 9093 mtod(m, const char *), tp, th); 9094 cc_conn_init(tp); 9095 } 9096 } else { 9097 /* 9098 * Received initial SYN in SYN-SENT[*] state => simultaneous 9099 * open. If segment contains CC option and there is a 9100 * cached CC, apply TAO test. If it succeeds, connection is * 9101 * half-synchronized. Otherwise, do 3-way handshake: 9102 * SYN-SENT -> SYN-RECEIVED SYN-SENT* -> SYN-RECEIVED* If 9103 * there was no CC option, clear cached CC value. 9104 */ 9105 tp->t_flags |= (TF_ACKNOW | TF_NEEDSYN); 9106 tcp_state_change(tp, TCPS_SYN_RECEIVED); 9107 } 9108 INP_WLOCK_ASSERT(tp->t_inpcb); 9109 /* 9110 * Advance th->th_seq to correspond to first data byte. If data, 9111 * trim to stay within window, dropping FIN if necessary. 9112 */ 9113 th->th_seq++; 9114 if (tlen > tp->rcv_wnd) { 9115 todrop = tlen - tp->rcv_wnd; 9116 m_adj(m, -todrop); 9117 tlen = tp->rcv_wnd; 9118 thflags &= ~TH_FIN; 9119 TCPSTAT_INC(tcps_rcvpackafterwin); 9120 TCPSTAT_ADD(tcps_rcvbyteafterwin, todrop); 9121 } 9122 tp->snd_wl1 = th->th_seq - 1; 9123 tp->rcv_up = th->th_seq; 9124 /* 9125 * Client side of transaction: already sent SYN and data. If the 9126 * remote host used T/TCP to validate the SYN, our data will be 9127 * ACK'd; if so, enter normal data segment processing in the middle 9128 * of step 5, ack processing. Otherwise, goto step 6. 9129 */ 9130 if (thflags & TH_ACK) { 9131 if ((to->to_flags & TOF_TS) != 0) { 9132 uint32_t t, rtt; 9133 9134 t = tcp_tv_to_mssectick(&bbr->rc_tv); 9135 if (TSTMP_GEQ(t, to->to_tsecr)) { 9136 rtt = t - to->to_tsecr; 9137 if (rtt == 0) { 9138 rtt = 1; 9139 } 9140 rtt *= MS_IN_USEC; 9141 tcp_bbr_xmit_timer(bbr, rtt, 0, 0, 0); 9142 apply_filter_min_small(&bbr->r_ctl.rc_rttprop, 9143 rtt, bbr->r_ctl.rc_rcvtime); 9144 } 9145 } 9146 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val)) 9147 return (ret_val); 9148 /* We may have changed to FIN_WAIT_1 above */ 9149 if (tp->t_state == TCPS_FIN_WAIT_1) { 9150 /* 9151 * In FIN_WAIT_1 STATE in addition to the processing 9152 * for the ESTABLISHED state if our FIN is now 9153 * acknowledged then enter FIN_WAIT_2. 9154 */ 9155 if (ourfinisacked) { 9156 /* 9157 * If we can't receive any more data, then 9158 * closing user can proceed. Starting the 9159 * timer is contrary to the specification, 9160 * but if we don't get a FIN we'll hang 9161 * forever. 9162 * 9163 * XXXjl: we should release the tp also, and 9164 * use a compressed state. 9165 */ 9166 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { 9167 soisdisconnected(so); 9168 tcp_timer_activate(tp, TT_2MSL, 9169 (tcp_fast_finwait2_recycle ? 9170 tcp_finwait2_timeout : 9171 TP_MAXIDLE(tp))); 9172 } 9173 tcp_state_change(tp, TCPS_FIN_WAIT_2); 9174 } 9175 } 9176 } 9177 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9178 tiwin, thflags, nxt_pkt)); 9179 } 9180 9181 /* 9182 * Return value of 1, the TCB is unlocked and most 9183 * likely gone, return value of 0, the TCB is still 9184 * locked. 9185 */ 9186 static int 9187 bbr_do_syn_recv(struct mbuf *m, struct tcphdr *th, struct socket *so, 9188 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, 9189 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt) 9190 { 9191 int32_t ourfinisacked = 0; 9192 int32_t ret_val; 9193 struct tcp_bbr *bbr; 9194 9195 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 9196 ctf_calc_rwin(so, tp); 9197 if ((thflags & TH_ACK) && 9198 (SEQ_LEQ(th->th_ack, tp->snd_una) || 9199 SEQ_GT(th->th_ack, tp->snd_max))) { 9200 ctf_do_dropwithreset(m, tp, th, BANDLIM_RST_OPENPORT, tlen); 9201 return (1); 9202 } 9203 if (IS_FASTOPEN(tp->t_flags)) { 9204 /* 9205 * When a TFO connection is in SYN_RECEIVED, the only valid 9206 * packets are the initial SYN, a retransmit/copy of the 9207 * initial SYN (possibly with a subset of the original 9208 * data), a valid ACK, a FIN, or a RST. 9209 */ 9210 if ((thflags & (TH_SYN | TH_ACK)) == (TH_SYN | TH_ACK)) { 9211 ctf_do_dropwithreset(m, tp, th, BANDLIM_RST_OPENPORT, tlen); 9212 return (1); 9213 } else if (thflags & TH_SYN) { 9214 /* non-initial SYN is ignored */ 9215 if ((bbr->r_ctl.rc_hpts_flags & PACE_TMR_RXT) || 9216 (bbr->r_ctl.rc_hpts_flags & PACE_TMR_TLP) || 9217 (bbr->r_ctl.rc_hpts_flags & PACE_TMR_RACK)) { 9218 ctf_do_drop(m, NULL); 9219 return (0); 9220 } 9221 } else if (!(thflags & (TH_ACK | TH_FIN | TH_RST))) { 9222 ctf_do_drop(m, NULL); 9223 return (0); 9224 } 9225 } 9226 if ((thflags & TH_RST) || 9227 (tp->t_fin_is_rst && (thflags & TH_FIN))) 9228 return (ctf_process_rst(m, th, so, tp)); 9229 /* 9230 * RFC 1323 PAWS: If we have a timestamp reply on this segment and 9231 * it's less than ts_recent, drop it. 9232 */ 9233 if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent && 9234 TSTMP_LT(to->to_tsval, tp->ts_recent)) { 9235 if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val)) 9236 return (ret_val); 9237 } 9238 /* 9239 * In the SYN-RECEIVED state, validate that the packet belongs to 9240 * this connection before trimming the data to fit the receive 9241 * window. Check the sequence number versus IRS since we know the 9242 * sequence numbers haven't wrapped. This is a partial fix for the 9243 * "LAND" DoS attack. 9244 */ 9245 if (SEQ_LT(th->th_seq, tp->irs)) { 9246 ctf_do_dropwithreset(m, tp, th, BANDLIM_RST_OPENPORT, tlen); 9247 return (1); 9248 } 9249 INP_WLOCK_ASSERT(tp->t_inpcb); 9250 if (ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val)) { 9251 return (ret_val); 9252 } 9253 /* 9254 * If last ACK falls within this segment's sequence numbers, record 9255 * its timestamp. NOTE: 1) That the test incorporates suggestions 9256 * from the latest proposal of the tcplw@cray.com list (Braden 9257 * 1993/04/26). 2) That updating only on newer timestamps interferes 9258 * with our earlier PAWS tests, so this check should be solely 9259 * predicated on the sequence space of this segment. 3) That we 9260 * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ 9261 * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ + 9262 * SEG.Len, This modified check allows us to overcome RFC1323's 9263 * limitations as described in Stevens TCP/IP Illustrated Vol. 2 9264 * p.869. In such cases, we can still calculate the RTT correctly 9265 * when RCV.NXT == Last.ACK.Sent. 9266 */ 9267 if ((to->to_flags & TOF_TS) != 0 && 9268 SEQ_LEQ(th->th_seq, tp->last_ack_sent) && 9269 SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen + 9270 ((thflags & (TH_SYN | TH_FIN)) != 0))) { 9271 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv); 9272 tp->ts_recent = to->to_tsval; 9273 } 9274 tp->snd_wnd = tiwin; 9275 /* 9276 * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag 9277 * is on (half-synchronized state), then queue data for later 9278 * processing; else drop segment and return. 9279 */ 9280 if ((thflags & TH_ACK) == 0) { 9281 if (IS_FASTOPEN(tp->t_flags)) { 9282 cc_conn_init(tp); 9283 } 9284 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9285 tiwin, thflags, nxt_pkt)); 9286 } 9287 TCPSTAT_INC(tcps_connects); 9288 soisconnected(so); 9289 /* Do window scaling? */ 9290 if ((tp->t_flags & (TF_RCVD_SCALE | TF_REQ_SCALE)) == 9291 (TF_RCVD_SCALE | TF_REQ_SCALE)) { 9292 tp->rcv_scale = tp->request_r_scale; 9293 } 9294 /* 9295 * ok for the first time in lets see if we can use the ts to figure 9296 * out what the initial RTT was. 9297 */ 9298 if ((to->to_flags & TOF_TS) != 0) { 9299 uint32_t t, rtt; 9300 9301 t = tcp_tv_to_mssectick(&bbr->rc_tv); 9302 if (TSTMP_GEQ(t, to->to_tsecr)) { 9303 rtt = t - to->to_tsecr; 9304 if (rtt == 0) { 9305 rtt = 1; 9306 } 9307 rtt *= MS_IN_USEC; 9308 tcp_bbr_xmit_timer(bbr, rtt, 0, 0, 0); 9309 apply_filter_min_small(&bbr->r_ctl.rc_rttprop, rtt, bbr->r_ctl.rc_rcvtime); 9310 } 9311 } 9312 /* Drop off any SYN in the send map (probably not there) */ 9313 if (thflags & TH_ACK) 9314 bbr_log_syn(tp, to); 9315 if (IS_FASTOPEN(tp->t_flags) && tp->t_tfo_pending) { 9316 9317 tcp_fastopen_decrement_counter(tp->t_tfo_pending); 9318 tp->t_tfo_pending = NULL; 9319 /* 9320 * Account for the ACK of our SYN prior to regular 9321 * ACK processing below. 9322 */ 9323 tp->snd_una++; 9324 } 9325 /* 9326 * Make transitions: SYN-RECEIVED -> ESTABLISHED SYN-RECEIVED* -> 9327 * FIN-WAIT-1 9328 */ 9329 tp->t_starttime = ticks; 9330 if (tp->t_flags & TF_NEEDFIN) { 9331 tcp_state_change(tp, TCPS_FIN_WAIT_1); 9332 tp->t_flags &= ~TF_NEEDFIN; 9333 } else { 9334 tcp_state_change(tp, TCPS_ESTABLISHED); 9335 TCP_PROBE5(accept__established, NULL, tp, 9336 mtod(m, const char *), tp, th); 9337 /* 9338 * TFO connections call cc_conn_init() during SYN 9339 * processing. Calling it again here for such connections 9340 * is not harmless as it would undo the snd_cwnd reduction 9341 * that occurs when a TFO SYN|ACK is retransmitted. 9342 */ 9343 if (!IS_FASTOPEN(tp->t_flags)) 9344 cc_conn_init(tp); 9345 } 9346 /* 9347 * If segment contains data or ACK, will call tcp_reass() later; if 9348 * not, do so now to pass queued data to user. 9349 */ 9350 if (tlen == 0 && (thflags & TH_FIN) == 0) 9351 (void)tcp_reass(tp, (struct tcphdr *)0, NULL, 0, 9352 (struct mbuf *)0); 9353 tp->snd_wl1 = th->th_seq - 1; 9354 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val)) { 9355 return (ret_val); 9356 } 9357 if (tp->t_state == TCPS_FIN_WAIT_1) { 9358 /* We could have went to FIN_WAIT_1 (or EST) above */ 9359 /* 9360 * In FIN_WAIT_1 STATE in addition to the processing for the 9361 * ESTABLISHED state if our FIN is now acknowledged then 9362 * enter FIN_WAIT_2. 9363 */ 9364 if (ourfinisacked) { 9365 /* 9366 * If we can't receive any more data, then closing 9367 * user can proceed. Starting the timer is contrary 9368 * to the specification, but if we don't get a FIN 9369 * we'll hang forever. 9370 * 9371 * XXXjl: we should release the tp also, and use a 9372 * compressed state. 9373 */ 9374 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { 9375 soisdisconnected(so); 9376 tcp_timer_activate(tp, TT_2MSL, 9377 (tcp_fast_finwait2_recycle ? 9378 tcp_finwait2_timeout : 9379 TP_MAXIDLE(tp))); 9380 } 9381 tcp_state_change(tp, TCPS_FIN_WAIT_2); 9382 } 9383 } 9384 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9385 tiwin, thflags, nxt_pkt)); 9386 } 9387 9388 /* 9389 * Return value of 1, the TCB is unlocked and most 9390 * likely gone, return value of 0, the TCB is still 9391 * locked. 9392 */ 9393 static int 9394 bbr_do_established(struct mbuf *m, struct tcphdr *th, struct socket *so, 9395 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, 9396 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt) 9397 { 9398 struct tcp_bbr *bbr; 9399 int32_t ret_val; 9400 9401 /* 9402 * Header prediction: check for the two common cases of a 9403 * uni-directional data xfer. If the packet has no control flags, 9404 * is in-sequence, the window didn't change and we're not 9405 * retransmitting, it's a candidate. If the length is zero and the 9406 * ack moved forward, we're the sender side of the xfer. Just free 9407 * the data acked & wake any higher level process that was blocked 9408 * waiting for space. If the length is non-zero and the ack didn't 9409 * move, we're the receiver side. If we're getting packets in-order 9410 * (the reassembly queue is empty), add the data toc The socket 9411 * buffer and note that we need a delayed ack. Make sure that the 9412 * hidden state-flags are also off. Since we check for 9413 * TCPS_ESTABLISHED first, it can only be TH_NEEDSYN. 9414 */ 9415 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 9416 if (bbr->r_ctl.rc_delivered < (4 * tp->t_maxseg)) { 9417 /* 9418 * If we have delived under 4 segments increase the initial 9419 * window if raised by the peer. We use this to determine 9420 * dynamic and static rwnd's at the end of a connection. 9421 */ 9422 bbr->r_ctl.rc_init_rwnd = max(tiwin, tp->snd_wnd); 9423 } 9424 if (__predict_true(((to->to_flags & TOF_SACK) == 0)) && 9425 __predict_true((thflags & (TH_SYN | TH_FIN | TH_RST | TH_URG | TH_ACK)) == TH_ACK) && 9426 __predict_true(SEGQ_EMPTY(tp)) && 9427 __predict_true(th->th_seq == tp->rcv_nxt)) { 9428 if (tlen == 0) { 9429 if (bbr_fastack(m, th, so, tp, to, drop_hdrlen, tlen, 9430 tiwin, nxt_pkt)) { 9431 return (0); 9432 } 9433 } else { 9434 if (bbr_do_fastnewdata(m, th, so, tp, to, drop_hdrlen, tlen, 9435 tiwin, nxt_pkt)) { 9436 return (0); 9437 } 9438 } 9439 } 9440 ctf_calc_rwin(so, tp); 9441 9442 if ((thflags & TH_RST) || 9443 (tp->t_fin_is_rst && (thflags & TH_FIN))) 9444 return (ctf_process_rst(m, th, so, tp)); 9445 /* 9446 * RFC5961 Section 4.2 Send challenge ACK for any SYN in 9447 * synchronized state. 9448 */ 9449 if (thflags & TH_SYN) { 9450 ctf_challenge_ack(m, th, tp, &ret_val); 9451 return (ret_val); 9452 } 9453 /* 9454 * RFC 1323 PAWS: If we have a timestamp reply on this segment and 9455 * it's less than ts_recent, drop it. 9456 */ 9457 if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent && 9458 TSTMP_LT(to->to_tsval, tp->ts_recent)) { 9459 if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val)) 9460 return (ret_val); 9461 } 9462 INP_WLOCK_ASSERT(tp->t_inpcb); 9463 if (ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val)) { 9464 return (ret_val); 9465 } 9466 /* 9467 * If last ACK falls within this segment's sequence numbers, record 9468 * its timestamp. NOTE: 1) That the test incorporates suggestions 9469 * from the latest proposal of the tcplw@cray.com list (Braden 9470 * 1993/04/26). 2) That updating only on newer timestamps interferes 9471 * with our earlier PAWS tests, so this check should be solely 9472 * predicated on the sequence space of this segment. 3) That we 9473 * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ 9474 * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ + 9475 * SEG.Len, This modified check allows us to overcome RFC1323's 9476 * limitations as described in Stevens TCP/IP Illustrated Vol. 2 9477 * p.869. In such cases, we can still calculate the RTT correctly 9478 * when RCV.NXT == Last.ACK.Sent. 9479 */ 9480 if ((to->to_flags & TOF_TS) != 0 && 9481 SEQ_LEQ(th->th_seq, tp->last_ack_sent) && 9482 SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen + 9483 ((thflags & (TH_SYN | TH_FIN)) != 0))) { 9484 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv); 9485 tp->ts_recent = to->to_tsval; 9486 } 9487 /* 9488 * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag 9489 * is on (half-synchronized state), then queue data for later 9490 * processing; else drop segment and return. 9491 */ 9492 if ((thflags & TH_ACK) == 0) { 9493 if (tp->t_flags & TF_NEEDSYN) { 9494 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9495 tiwin, thflags, nxt_pkt)); 9496 } else if (tp->t_flags & TF_ACKNOW) { 9497 ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val); 9498 bbr->r_wanted_output = 1; 9499 return (ret_val); 9500 } else { 9501 ctf_do_drop(m, NULL); 9502 return (0); 9503 } 9504 } 9505 /* 9506 * Ack processing. 9507 */ 9508 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, NULL, thflags, &ret_val)) { 9509 return (ret_val); 9510 } 9511 if (sbavail(&so->so_snd)) { 9512 if (bbr_progress_timeout_check(bbr)) { 9513 ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen); 9514 return (1); 9515 } 9516 } 9517 /* State changes only happen in bbr_process_data() */ 9518 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9519 tiwin, thflags, nxt_pkt)); 9520 } 9521 9522 /* 9523 * Return value of 1, the TCB is unlocked and most 9524 * likely gone, return value of 0, the TCB is still 9525 * locked. 9526 */ 9527 static int 9528 bbr_do_close_wait(struct mbuf *m, struct tcphdr *th, struct socket *so, 9529 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, 9530 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt) 9531 { 9532 struct tcp_bbr *bbr; 9533 int32_t ret_val; 9534 9535 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 9536 ctf_calc_rwin(so, tp); 9537 if ((thflags & TH_RST) || 9538 (tp->t_fin_is_rst && (thflags & TH_FIN))) 9539 return (ctf_process_rst(m, th, so, tp)); 9540 /* 9541 * RFC5961 Section 4.2 Send challenge ACK for any SYN in 9542 * synchronized state. 9543 */ 9544 if (thflags & TH_SYN) { 9545 ctf_challenge_ack(m, th, tp, &ret_val); 9546 return (ret_val); 9547 } 9548 /* 9549 * RFC 1323 PAWS: If we have a timestamp reply on this segment and 9550 * it's less than ts_recent, drop it. 9551 */ 9552 if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent && 9553 TSTMP_LT(to->to_tsval, tp->ts_recent)) { 9554 if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val)) 9555 return (ret_val); 9556 } 9557 INP_WLOCK_ASSERT(tp->t_inpcb); 9558 if (ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val)) { 9559 return (ret_val); 9560 } 9561 /* 9562 * If last ACK falls within this segment's sequence numbers, record 9563 * its timestamp. NOTE: 1) That the test incorporates suggestions 9564 * from the latest proposal of the tcplw@cray.com list (Braden 9565 * 1993/04/26). 2) That updating only on newer timestamps interferes 9566 * with our earlier PAWS tests, so this check should be solely 9567 * predicated on the sequence space of this segment. 3) That we 9568 * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ 9569 * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ + 9570 * SEG.Len, This modified check allows us to overcome RFC1323's 9571 * limitations as described in Stevens TCP/IP Illustrated Vol. 2 9572 * p.869. In such cases, we can still calculate the RTT correctly 9573 * when RCV.NXT == Last.ACK.Sent. 9574 */ 9575 if ((to->to_flags & TOF_TS) != 0 && 9576 SEQ_LEQ(th->th_seq, tp->last_ack_sent) && 9577 SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen + 9578 ((thflags & (TH_SYN | TH_FIN)) != 0))) { 9579 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv); 9580 tp->ts_recent = to->to_tsval; 9581 } 9582 /* 9583 * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag 9584 * is on (half-synchronized state), then queue data for later 9585 * processing; else drop segment and return. 9586 */ 9587 if ((thflags & TH_ACK) == 0) { 9588 if (tp->t_flags & TF_NEEDSYN) { 9589 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9590 tiwin, thflags, nxt_pkt)); 9591 } else if (tp->t_flags & TF_ACKNOW) { 9592 ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val); 9593 bbr->r_wanted_output = 1; 9594 return (ret_val); 9595 } else { 9596 ctf_do_drop(m, NULL); 9597 return (0); 9598 } 9599 } 9600 /* 9601 * Ack processing. 9602 */ 9603 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, NULL, thflags, &ret_val)) { 9604 return (ret_val); 9605 } 9606 if (sbavail(&so->so_snd)) { 9607 if (bbr_progress_timeout_check(bbr)) { 9608 ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen); 9609 return (1); 9610 } 9611 } 9612 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9613 tiwin, thflags, nxt_pkt)); 9614 } 9615 9616 static int 9617 bbr_check_data_after_close(struct mbuf *m, struct tcp_bbr *bbr, 9618 struct tcpcb *tp, int32_t * tlen, struct tcphdr *th, struct socket *so) 9619 { 9620 9621 if (bbr->rc_allow_data_af_clo == 0) { 9622 close_now: 9623 tp = tcp_close(tp); 9624 TCPSTAT_INC(tcps_rcvafterclose); 9625 ctf_do_dropwithreset(m, tp, th, BANDLIM_UNLIMITED, (*tlen)); 9626 return (1); 9627 } 9628 if (sbavail(&so->so_snd) == 0) 9629 goto close_now; 9630 /* Ok we allow data that is ignored and a followup reset */ 9631 tp->rcv_nxt = th->th_seq + *tlen; 9632 tp->t_flags2 |= TF2_DROP_AF_DATA; 9633 bbr->r_wanted_output = 1; 9634 *tlen = 0; 9635 return (0); 9636 } 9637 9638 /* 9639 * Return value of 1, the TCB is unlocked and most 9640 * likely gone, return value of 0, the TCB is still 9641 * locked. 9642 */ 9643 static int 9644 bbr_do_fin_wait_1(struct mbuf *m, struct tcphdr *th, struct socket *so, 9645 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, 9646 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt) 9647 { 9648 int32_t ourfinisacked = 0; 9649 int32_t ret_val; 9650 struct tcp_bbr *bbr; 9651 9652 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 9653 ctf_calc_rwin(so, tp); 9654 if ((thflags & TH_RST) || 9655 (tp->t_fin_is_rst && (thflags & TH_FIN))) 9656 return (ctf_process_rst(m, th, so, tp)); 9657 /* 9658 * RFC5961 Section 4.2 Send challenge ACK for any SYN in 9659 * synchronized state. 9660 */ 9661 if (thflags & TH_SYN) { 9662 ctf_challenge_ack(m, th, tp, &ret_val); 9663 return (ret_val); 9664 } 9665 /* 9666 * RFC 1323 PAWS: If we have a timestamp reply on this segment and 9667 * it's less than ts_recent, drop it. 9668 */ 9669 if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent && 9670 TSTMP_LT(to->to_tsval, tp->ts_recent)) { 9671 if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val)) 9672 return (ret_val); 9673 } 9674 INP_WLOCK_ASSERT(tp->t_inpcb); 9675 if (ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val)) { 9676 return (ret_val); 9677 } 9678 /* 9679 * If new data are received on a connection after the user processes 9680 * are gone, then RST the other end. 9681 */ 9682 if ((so->so_state & SS_NOFDREF) && tlen) { 9683 /* 9684 * We call a new function now so we might continue and setup 9685 * to reset at all data being ack'd. 9686 */ 9687 if (bbr_check_data_after_close(m, bbr, tp, &tlen, th, so)) 9688 return (1); 9689 } 9690 /* 9691 * If last ACK falls within this segment's sequence numbers, record 9692 * its timestamp. NOTE: 1) That the test incorporates suggestions 9693 * from the latest proposal of the tcplw@cray.com list (Braden 9694 * 1993/04/26). 2) That updating only on newer timestamps interferes 9695 * with our earlier PAWS tests, so this check should be solely 9696 * predicated on the sequence space of this segment. 3) That we 9697 * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ 9698 * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ + 9699 * SEG.Len, This modified check allows us to overcome RFC1323's 9700 * limitations as described in Stevens TCP/IP Illustrated Vol. 2 9701 * p.869. In such cases, we can still calculate the RTT correctly 9702 * when RCV.NXT == Last.ACK.Sent. 9703 */ 9704 if ((to->to_flags & TOF_TS) != 0 && 9705 SEQ_LEQ(th->th_seq, tp->last_ack_sent) && 9706 SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen + 9707 ((thflags & (TH_SYN | TH_FIN)) != 0))) { 9708 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv); 9709 tp->ts_recent = to->to_tsval; 9710 } 9711 /* 9712 * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag 9713 * is on (half-synchronized state), then queue data for later 9714 * processing; else drop segment and return. 9715 */ 9716 if ((thflags & TH_ACK) == 0) { 9717 if (tp->t_flags & TF_NEEDSYN) { 9718 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9719 tiwin, thflags, nxt_pkt)); 9720 } else if (tp->t_flags & TF_ACKNOW) { 9721 ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val); 9722 bbr->r_wanted_output = 1; 9723 return (ret_val); 9724 } else { 9725 ctf_do_drop(m, NULL); 9726 return (0); 9727 } 9728 } 9729 /* 9730 * Ack processing. 9731 */ 9732 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val)) { 9733 return (ret_val); 9734 } 9735 if (ourfinisacked) { 9736 /* 9737 * If we can't receive any more data, then closing user can 9738 * proceed. Starting the timer is contrary to the 9739 * specification, but if we don't get a FIN we'll hang 9740 * forever. 9741 * 9742 * XXXjl: we should release the tp also, and use a 9743 * compressed state. 9744 */ 9745 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { 9746 soisdisconnected(so); 9747 tcp_timer_activate(tp, TT_2MSL, 9748 (tcp_fast_finwait2_recycle ? 9749 tcp_finwait2_timeout : 9750 TP_MAXIDLE(tp))); 9751 } 9752 tcp_state_change(tp, TCPS_FIN_WAIT_2); 9753 } 9754 if (sbavail(&so->so_snd)) { 9755 if (bbr_progress_timeout_check(bbr)) { 9756 ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen); 9757 return (1); 9758 } 9759 } 9760 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9761 tiwin, thflags, nxt_pkt)); 9762 } 9763 9764 /* 9765 * Return value of 1, the TCB is unlocked and most 9766 * likely gone, return value of 0, the TCB is still 9767 * locked. 9768 */ 9769 static int 9770 bbr_do_closing(struct mbuf *m, struct tcphdr *th, struct socket *so, 9771 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, 9772 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt) 9773 { 9774 int32_t ourfinisacked = 0; 9775 int32_t ret_val; 9776 struct tcp_bbr *bbr; 9777 9778 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 9779 ctf_calc_rwin(so, tp); 9780 if ((thflags & TH_RST) || 9781 (tp->t_fin_is_rst && (thflags & TH_FIN))) 9782 return (ctf_process_rst(m, th, so, tp)); 9783 /* 9784 * RFC5961 Section 4.2 Send challenge ACK for any SYN in 9785 * synchronized state. 9786 */ 9787 if (thflags & TH_SYN) { 9788 ctf_challenge_ack(m, th, tp, &ret_val); 9789 return (ret_val); 9790 } 9791 /* 9792 * RFC 1323 PAWS: If we have a timestamp reply on this segment and 9793 * it's less than ts_recent, drop it. 9794 */ 9795 if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent && 9796 TSTMP_LT(to->to_tsval, tp->ts_recent)) { 9797 if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val)) 9798 return (ret_val); 9799 } 9800 INP_WLOCK_ASSERT(tp->t_inpcb); 9801 if (ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val)) { 9802 return (ret_val); 9803 } 9804 /* 9805 * If new data are received on a connection after the user processes 9806 * are gone, then RST the other end. 9807 */ 9808 if ((so->so_state & SS_NOFDREF) && tlen) { 9809 /* 9810 * We call a new function now so we might continue and setup 9811 * to reset at all data being ack'd. 9812 */ 9813 if (bbr_check_data_after_close(m, bbr, tp, &tlen, th, so)) 9814 return (1); 9815 } 9816 /* 9817 * If last ACK falls within this segment's sequence numbers, record 9818 * its timestamp. NOTE: 1) That the test incorporates suggestions 9819 * from the latest proposal of the tcplw@cray.com list (Braden 9820 * 1993/04/26). 2) That updating only on newer timestamps interferes 9821 * with our earlier PAWS tests, so this check should be solely 9822 * predicated on the sequence space of this segment. 3) That we 9823 * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ 9824 * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ + 9825 * SEG.Len, This modified check allows us to overcome RFC1323's 9826 * limitations as described in Stevens TCP/IP Illustrated Vol. 2 9827 * p.869. In such cases, we can still calculate the RTT correctly 9828 * when RCV.NXT == Last.ACK.Sent. 9829 */ 9830 if ((to->to_flags & TOF_TS) != 0 && 9831 SEQ_LEQ(th->th_seq, tp->last_ack_sent) && 9832 SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen + 9833 ((thflags & (TH_SYN | TH_FIN)) != 0))) { 9834 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv); 9835 tp->ts_recent = to->to_tsval; 9836 } 9837 /* 9838 * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag 9839 * is on (half-synchronized state), then queue data for later 9840 * processing; else drop segment and return. 9841 */ 9842 if ((thflags & TH_ACK) == 0) { 9843 if (tp->t_flags & TF_NEEDSYN) { 9844 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9845 tiwin, thflags, nxt_pkt)); 9846 } else if (tp->t_flags & TF_ACKNOW) { 9847 ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val); 9848 bbr->r_wanted_output = 1; 9849 return (ret_val); 9850 } else { 9851 ctf_do_drop(m, NULL); 9852 return (0); 9853 } 9854 } 9855 /* 9856 * Ack processing. 9857 */ 9858 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val)) { 9859 return (ret_val); 9860 } 9861 if (ourfinisacked) { 9862 tcp_twstart(tp); 9863 m_freem(m); 9864 return (1); 9865 } 9866 if (sbavail(&so->so_snd)) { 9867 if (bbr_progress_timeout_check(bbr)) { 9868 ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen); 9869 return (1); 9870 } 9871 } 9872 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9873 tiwin, thflags, nxt_pkt)); 9874 } 9875 9876 /* 9877 * Return value of 1, the TCB is unlocked and most 9878 * likely gone, return value of 0, the TCB is still 9879 * locked. 9880 */ 9881 static int 9882 bbr_do_lastack(struct mbuf *m, struct tcphdr *th, struct socket *so, 9883 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, 9884 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt) 9885 { 9886 int32_t ourfinisacked = 0; 9887 int32_t ret_val; 9888 struct tcp_bbr *bbr; 9889 9890 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 9891 ctf_calc_rwin(so, tp); 9892 if ((thflags & TH_RST) || 9893 (tp->t_fin_is_rst && (thflags & TH_FIN))) 9894 return (ctf_process_rst(m, th, so, tp)); 9895 /* 9896 * RFC5961 Section 4.2 Send challenge ACK for any SYN in 9897 * synchronized state. 9898 */ 9899 if (thflags & TH_SYN) { 9900 ctf_challenge_ack(m, th, tp, &ret_val); 9901 return (ret_val); 9902 } 9903 /* 9904 * RFC 1323 PAWS: If we have a timestamp reply on this segment and 9905 * it's less than ts_recent, drop it. 9906 */ 9907 if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent && 9908 TSTMP_LT(to->to_tsval, tp->ts_recent)) { 9909 if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val)) 9910 return (ret_val); 9911 } 9912 INP_WLOCK_ASSERT(tp->t_inpcb); 9913 if (ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val)) { 9914 return (ret_val); 9915 } 9916 /* 9917 * If new data are received on a connection after the user processes 9918 * are gone, then RST the other end. 9919 */ 9920 if ((so->so_state & SS_NOFDREF) && tlen) { 9921 /* 9922 * We call a new function now so we might continue and setup 9923 * to reset at all data being ack'd. 9924 */ 9925 if (bbr_check_data_after_close(m, bbr, tp, &tlen, th, so)) 9926 return (1); 9927 } 9928 /* 9929 * If last ACK falls within this segment's sequence numbers, record 9930 * its timestamp. NOTE: 1) That the test incorporates suggestions 9931 * from the latest proposal of the tcplw@cray.com list (Braden 9932 * 1993/04/26). 2) That updating only on newer timestamps interferes 9933 * with our earlier PAWS tests, so this check should be solely 9934 * predicated on the sequence space of this segment. 3) That we 9935 * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ 9936 * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ + 9937 * SEG.Len, This modified check allows us to overcome RFC1323's 9938 * limitations as described in Stevens TCP/IP Illustrated Vol. 2 9939 * p.869. In such cases, we can still calculate the RTT correctly 9940 * when RCV.NXT == Last.ACK.Sent. 9941 */ 9942 if ((to->to_flags & TOF_TS) != 0 && 9943 SEQ_LEQ(th->th_seq, tp->last_ack_sent) && 9944 SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen + 9945 ((thflags & (TH_SYN | TH_FIN)) != 0))) { 9946 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv); 9947 tp->ts_recent = to->to_tsval; 9948 } 9949 /* 9950 * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag 9951 * is on (half-synchronized state), then queue data for later 9952 * processing; else drop segment and return. 9953 */ 9954 if ((thflags & TH_ACK) == 0) { 9955 if (tp->t_flags & TF_NEEDSYN) { 9956 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9957 tiwin, thflags, nxt_pkt)); 9958 } else if (tp->t_flags & TF_ACKNOW) { 9959 ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val); 9960 bbr->r_wanted_output = 1; 9961 return (ret_val); 9962 } else { 9963 ctf_do_drop(m, NULL); 9964 return (0); 9965 } 9966 } 9967 /* 9968 * case TCPS_LAST_ACK: Ack processing. 9969 */ 9970 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val)) { 9971 return (ret_val); 9972 } 9973 if (ourfinisacked) { 9974 tp = tcp_close(tp); 9975 ctf_do_drop(m, tp); 9976 return (1); 9977 } 9978 if (sbavail(&so->so_snd)) { 9979 if (bbr_progress_timeout_check(bbr)) { 9980 ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen); 9981 return (1); 9982 } 9983 } 9984 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9985 tiwin, thflags, nxt_pkt)); 9986 } 9987 9988 9989 /* 9990 * Return value of 1, the TCB is unlocked and most 9991 * likely gone, return value of 0, the TCB is still 9992 * locked. 9993 */ 9994 static int 9995 bbr_do_fin_wait_2(struct mbuf *m, struct tcphdr *th, struct socket *so, 9996 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, 9997 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt) 9998 { 9999 int32_t ourfinisacked = 0; 10000 int32_t ret_val; 10001 struct tcp_bbr *bbr; 10002 10003 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 10004 ctf_calc_rwin(so, tp); 10005 /* Reset receive buffer auto scaling when not in bulk receive mode. */ 10006 if ((thflags & TH_RST) || 10007 (tp->t_fin_is_rst && (thflags & TH_FIN))) 10008 return (ctf_process_rst(m, th, so, tp)); 10009 10010 /* 10011 * RFC5961 Section 4.2 Send challenge ACK for any SYN in 10012 * synchronized state. 10013 */ 10014 if (thflags & TH_SYN) { 10015 ctf_challenge_ack(m, th, tp, &ret_val); 10016 return (ret_val); 10017 } 10018 INP_WLOCK_ASSERT(tp->t_inpcb); 10019 /* 10020 * RFC 1323 PAWS: If we have a timestamp reply on this segment and 10021 * it's less than ts_recent, drop it. 10022 */ 10023 if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent && 10024 TSTMP_LT(to->to_tsval, tp->ts_recent)) { 10025 if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val)) 10026 return (ret_val); 10027 } 10028 INP_WLOCK_ASSERT(tp->t_inpcb); 10029 if (ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val)) { 10030 return (ret_val); 10031 } 10032 /* 10033 * If new data are received on a connection after the user processes 10034 * are gone, then we may RST the other end depending on the outcome 10035 * of bbr_check_data_after_close. 10036 */ 10037 if ((so->so_state & SS_NOFDREF) && 10038 tlen) { 10039 /* 10040 * We call a new function now so we might continue and setup 10041 * to reset at all data being ack'd. 10042 */ 10043 if (bbr_check_data_after_close(m, bbr, tp, &tlen, th, so)) 10044 return (1); 10045 } 10046 INP_WLOCK_ASSERT(tp->t_inpcb); 10047 /* 10048 * If last ACK falls within this segment's sequence numbers, record 10049 * its timestamp. NOTE: 1) That the test incorporates suggestions 10050 * from the latest proposal of the tcplw@cray.com list (Braden 10051 * 1993/04/26). 2) That updating only on newer timestamps interferes 10052 * with our earlier PAWS tests, so this check should be solely 10053 * predicated on the sequence space of this segment. 3) That we 10054 * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ 10055 * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ + 10056 * SEG.Len, This modified check allows us to overcome RFC1323's 10057 * limitations as described in Stevens TCP/IP Illustrated Vol. 2 10058 * p.869. In such cases, we can still calculate the RTT correctly 10059 * when RCV.NXT == Last.ACK.Sent. 10060 */ 10061 INP_WLOCK_ASSERT(tp->t_inpcb); 10062 if ((to->to_flags & TOF_TS) != 0 && 10063 SEQ_LEQ(th->th_seq, tp->last_ack_sent) && 10064 SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen + 10065 ((thflags & (TH_SYN | TH_FIN)) != 0))) { 10066 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv); 10067 tp->ts_recent = to->to_tsval; 10068 } 10069 /* 10070 * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag 10071 * is on (half-synchronized state), then queue data for later 10072 * processing; else drop segment and return. 10073 */ 10074 if ((thflags & TH_ACK) == 0) { 10075 if (tp->t_flags & TF_NEEDSYN) { 10076 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 10077 tiwin, thflags, nxt_pkt)); 10078 } else if (tp->t_flags & TF_ACKNOW) { 10079 ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val); 10080 bbr->r_wanted_output = 1; 10081 return (ret_val); 10082 } else { 10083 ctf_do_drop(m, NULL); 10084 return (0); 10085 } 10086 } 10087 /* 10088 * Ack processing. 10089 */ 10090 INP_WLOCK_ASSERT(tp->t_inpcb); 10091 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val)) { 10092 return (ret_val); 10093 } 10094 if (sbavail(&so->so_snd)) { 10095 if (bbr_progress_timeout_check(bbr)) { 10096 ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen); 10097 return (1); 10098 } 10099 } 10100 INP_WLOCK_ASSERT(tp->t_inpcb); 10101 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 10102 tiwin, thflags, nxt_pkt)); 10103 } 10104 10105 static void 10106 bbr_stop_all_timers(struct tcpcb *tp) 10107 { 10108 struct tcp_bbr *bbr; 10109 10110 /* 10111 * Assure no timers are running. 10112 */ 10113 if (tcp_timer_active(tp, TT_PERSIST)) { 10114 /* We enter in persists, set the flag appropriately */ 10115 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 10116 bbr->rc_in_persist = 1; 10117 } 10118 tcp_timer_suspend(tp, TT_PERSIST); 10119 tcp_timer_suspend(tp, TT_REXMT); 10120 tcp_timer_suspend(tp, TT_KEEP); 10121 tcp_timer_suspend(tp, TT_DELACK); 10122 } 10123 10124 static void 10125 bbr_google_mode_on(struct tcp_bbr *bbr) 10126 { 10127 bbr->rc_use_google = 1; 10128 bbr->rc_no_pacing = 0; 10129 bbr->r_ctl.bbr_google_discount = bbr_google_discount; 10130 bbr->r_use_policer = bbr_policer_detection_enabled; 10131 bbr->r_ctl.rc_probertt_int = (USECS_IN_SECOND * 10); 10132 bbr->bbr_use_rack_cheat = 0; 10133 bbr->r_ctl.rc_incr_tmrs = 0; 10134 bbr->r_ctl.rc_inc_tcp_oh = 0; 10135 bbr->r_ctl.rc_inc_ip_oh = 0; 10136 bbr->r_ctl.rc_inc_enet_oh = 0; 10137 reset_time(&bbr->r_ctl.rc_delrate, 10138 BBR_NUM_RTTS_FOR_GOOG_DEL_LIMIT); 10139 reset_time_small(&bbr->r_ctl.rc_rttprop, 10140 (11 * USECS_IN_SECOND)); 10141 tcp_bbr_tso_size_check(bbr, tcp_get_usecs(&bbr->rc_tv)); 10142 } 10143 10144 static void 10145 bbr_google_mode_off(struct tcp_bbr *bbr) 10146 { 10147 bbr->rc_use_google = 0; 10148 bbr->r_ctl.bbr_google_discount = 0; 10149 bbr->no_pacing_until = bbr_no_pacing_until; 10150 bbr->r_use_policer = 0; 10151 if (bbr->no_pacing_until) 10152 bbr->rc_no_pacing = 1; 10153 else 10154 bbr->rc_no_pacing = 0; 10155 if (bbr_use_rack_resend_cheat) 10156 bbr->bbr_use_rack_cheat = 1; 10157 else 10158 bbr->bbr_use_rack_cheat = 0; 10159 if (bbr_incr_timers) 10160 bbr->r_ctl.rc_incr_tmrs = 1; 10161 else 10162 bbr->r_ctl.rc_incr_tmrs = 0; 10163 if (bbr_include_tcp_oh) 10164 bbr->r_ctl.rc_inc_tcp_oh = 1; 10165 else 10166 bbr->r_ctl.rc_inc_tcp_oh = 0; 10167 if (bbr_include_ip_oh) 10168 bbr->r_ctl.rc_inc_ip_oh = 1; 10169 else 10170 bbr->r_ctl.rc_inc_ip_oh = 0; 10171 if (bbr_include_enet_oh) 10172 bbr->r_ctl.rc_inc_enet_oh = 1; 10173 else 10174 bbr->r_ctl.rc_inc_enet_oh = 0; 10175 bbr->r_ctl.rc_probertt_int = bbr_rtt_probe_limit; 10176 reset_time(&bbr->r_ctl.rc_delrate, 10177 bbr_num_pktepo_for_del_limit); 10178 reset_time_small(&bbr->r_ctl.rc_rttprop, 10179 (bbr_filter_len_sec * USECS_IN_SECOND)); 10180 tcp_bbr_tso_size_check(bbr, tcp_get_usecs(&bbr->rc_tv)); 10181 } 10182 /* 10183 * Return 0 on success, non-zero on failure 10184 * which indicates the error (usually no memory). 10185 */ 10186 static int 10187 bbr_init(struct tcpcb *tp) 10188 { 10189 struct tcp_bbr *bbr = NULL; 10190 struct inpcb *inp; 10191 uint32_t cts; 10192 10193 tp->t_fb_ptr = uma_zalloc(bbr_pcb_zone, (M_NOWAIT | M_ZERO)); 10194 if (tp->t_fb_ptr == NULL) { 10195 /* 10196 * We need to allocate memory but cant. The INP and INP_INFO 10197 * locks and they are recusive (happens during setup. So a 10198 * scheme to drop the locks fails :( 10199 * 10200 */ 10201 return (ENOMEM); 10202 } 10203 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 10204 bbr->rtt_valid = 0; 10205 inp = tp->t_inpcb; 10206 inp->inp_flags2 |= INP_CANNOT_DO_ECN; 10207 inp->inp_flags2 |= INP_SUPPORTS_MBUFQ; 10208 TAILQ_INIT(&bbr->r_ctl.rc_map); 10209 TAILQ_INIT(&bbr->r_ctl.rc_free); 10210 TAILQ_INIT(&bbr->r_ctl.rc_tmap); 10211 bbr->rc_tp = tp; 10212 if (tp->t_inpcb) { 10213 bbr->rc_inp = tp->t_inpcb; 10214 } 10215 cts = tcp_get_usecs(&bbr->rc_tv); 10216 tp->t_acktime = 0; 10217 bbr->rc_allow_data_af_clo = bbr_ignore_data_after_close; 10218 bbr->r_ctl.rc_reorder_fade = bbr_reorder_fade; 10219 bbr->rc_tlp_threshold = bbr_tlp_thresh; 10220 bbr->r_ctl.rc_reorder_shift = bbr_reorder_thresh; 10221 bbr->r_ctl.rc_pkt_delay = bbr_pkt_delay; 10222 bbr->r_ctl.rc_min_to = bbr_min_to; 10223 bbr->rc_bbr_state = BBR_STATE_STARTUP; 10224 bbr->r_ctl.bbr_lost_at_state = 0; 10225 bbr->r_ctl.rc_lost_at_startup = 0; 10226 bbr->rc_all_timers_stopped = 0; 10227 bbr->r_ctl.rc_bbr_lastbtlbw = 0; 10228 bbr->r_ctl.rc_pkt_epoch_del = 0; 10229 bbr->r_ctl.rc_pkt_epoch = 0; 10230 bbr->r_ctl.rc_lowest_rtt = 0xffffffff; 10231 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_high_gain; 10232 bbr->r_ctl.rc_bbr_cwnd_gain = bbr_high_gain; 10233 bbr->r_ctl.rc_went_idle_time = cts; 10234 bbr->rc_pacer_started = cts; 10235 bbr->r_ctl.rc_pkt_epoch_time = cts; 10236 bbr->r_ctl.rc_rcvtime = cts; 10237 bbr->r_ctl.rc_bbr_state_time = cts; 10238 bbr->r_ctl.rc_del_time = cts; 10239 bbr->r_ctl.rc_tlp_rxt_last_time = cts; 10240 bbr->r_ctl.last_in_probertt = cts; 10241 bbr->skip_gain = 0; 10242 bbr->gain_is_limited = 0; 10243 bbr->no_pacing_until = bbr_no_pacing_until; 10244 if (bbr->no_pacing_until) 10245 bbr->rc_no_pacing = 1; 10246 if (bbr_use_google_algo) { 10247 bbr->rc_no_pacing = 0; 10248 bbr->rc_use_google = 1; 10249 bbr->r_ctl.bbr_google_discount = bbr_google_discount; 10250 bbr->r_use_policer = bbr_policer_detection_enabled; 10251 } else { 10252 bbr->rc_use_google = 0; 10253 bbr->r_ctl.bbr_google_discount = 0; 10254 bbr->r_use_policer = 0; 10255 } 10256 if (bbr_ts_limiting) 10257 bbr->rc_use_ts_limit = 1; 10258 else 10259 bbr->rc_use_ts_limit = 0; 10260 if (bbr_ts_can_raise) 10261 bbr->ts_can_raise = 1; 10262 else 10263 bbr->ts_can_raise = 0; 10264 if (V_tcp_delack_enabled == 1) 10265 tp->t_delayed_ack = 2; 10266 else if (V_tcp_delack_enabled == 0) 10267 tp->t_delayed_ack = 0; 10268 else if (V_tcp_delack_enabled < 100) 10269 tp->t_delayed_ack = V_tcp_delack_enabled; 10270 else 10271 tp->t_delayed_ack = 2; 10272 if (bbr->rc_use_google == 0) 10273 bbr->r_ctl.rc_probertt_int = bbr_rtt_probe_limit; 10274 else 10275 bbr->r_ctl.rc_probertt_int = (USECS_IN_SECOND * 10); 10276 bbr->r_ctl.rc_min_rto_ms = bbr_rto_min_ms; 10277 bbr->rc_max_rto_sec = bbr_rto_max_sec; 10278 bbr->rc_init_win = bbr_def_init_win; 10279 if (tp->t_flags & TF_REQ_TSTMP) 10280 bbr->rc_last_options = TCP_TS_OVERHEAD; 10281 bbr->r_ctl.rc_pace_max_segs = tp->t_maxseg - bbr->rc_last_options; 10282 bbr->r_ctl.rc_high_rwnd = tp->snd_wnd; 10283 bbr->r_init_rtt = 1; 10284 10285 counter_u64_add(bbr_flows_nohdwr_pacing, 1); 10286 if (bbr_allow_hdwr_pacing) 10287 bbr->bbr_hdw_pace_ena = 1; 10288 else 10289 bbr->bbr_hdw_pace_ena = 0; 10290 if (bbr_sends_full_iwnd) 10291 bbr->bbr_init_win_cheat = 1; 10292 else 10293 bbr->bbr_init_win_cheat = 0; 10294 bbr->r_ctl.bbr_utter_max = bbr_hptsi_utter_max; 10295 bbr->r_ctl.rc_drain_pg = bbr_drain_gain; 10296 bbr->r_ctl.rc_startup_pg = bbr_high_gain; 10297 bbr->rc_loss_exit = bbr_exit_startup_at_loss; 10298 bbr->r_ctl.bbr_rttprobe_gain_val = bbr_rttprobe_gain; 10299 bbr->r_ctl.bbr_hptsi_per_second = bbr_hptsi_per_second; 10300 bbr->r_ctl.bbr_hptsi_segments_delay_tar = bbr_hptsi_segments_delay_tar; 10301 bbr->r_ctl.bbr_hptsi_segments_max = bbr_hptsi_segments_max; 10302 bbr->r_ctl.bbr_hptsi_segments_floor = bbr_hptsi_segments_floor; 10303 bbr->r_ctl.bbr_hptsi_bytes_min = bbr_hptsi_bytes_min; 10304 bbr->r_ctl.bbr_cross_over = bbr_cross_over; 10305 bbr->r_ctl.rc_rtt_shrinks = cts; 10306 if (bbr->rc_use_google) { 10307 setup_time_filter(&bbr->r_ctl.rc_delrate, 10308 FILTER_TYPE_MAX, 10309 BBR_NUM_RTTS_FOR_GOOG_DEL_LIMIT); 10310 setup_time_filter_small(&bbr->r_ctl.rc_rttprop, 10311 FILTER_TYPE_MIN, (11 * USECS_IN_SECOND)); 10312 } else { 10313 setup_time_filter(&bbr->r_ctl.rc_delrate, 10314 FILTER_TYPE_MAX, 10315 bbr_num_pktepo_for_del_limit); 10316 setup_time_filter_small(&bbr->r_ctl.rc_rttprop, 10317 FILTER_TYPE_MIN, (bbr_filter_len_sec * USECS_IN_SECOND)); 10318 } 10319 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_INIT, 0); 10320 if (bbr_uses_idle_restart) 10321 bbr->rc_use_idle_restart = 1; 10322 else 10323 bbr->rc_use_idle_restart = 0; 10324 bbr->r_ctl.rc_bbr_cur_del_rate = 0; 10325 bbr->r_ctl.rc_initial_hptsi_bw = bbr_initial_bw_bps; 10326 if (bbr_resends_use_tso) 10327 bbr->rc_resends_use_tso = 1; 10328 #ifdef NETFLIX_PEAKRATE 10329 tp->t_peakrate_thr = tp->t_maxpeakrate; 10330 #endif 10331 if (tp->snd_una != tp->snd_max) { 10332 /* Create a send map for the current outstanding data */ 10333 struct bbr_sendmap *rsm; 10334 10335 rsm = bbr_alloc(bbr); 10336 if (rsm == NULL) { 10337 uma_zfree(bbr_pcb_zone, tp->t_fb_ptr); 10338 tp->t_fb_ptr = NULL; 10339 return (ENOMEM); 10340 } 10341 rsm->r_flags = BBR_OVERMAX; 10342 rsm->r_tim_lastsent[0] = cts; 10343 rsm->r_rtr_cnt = 1; 10344 rsm->r_rtr_bytes = 0; 10345 rsm->r_start = tp->snd_una; 10346 rsm->r_end = tp->snd_max; 10347 rsm->r_dupack = 0; 10348 rsm->r_delivered = bbr->r_ctl.rc_delivered; 10349 rsm->r_ts_valid = 0; 10350 rsm->r_del_ack_ts = tp->ts_recent; 10351 rsm->r_del_time = cts; 10352 if (bbr->r_ctl.r_app_limited_until) 10353 rsm->r_app_limited = 1; 10354 else 10355 rsm->r_app_limited = 0; 10356 TAILQ_INSERT_TAIL(&bbr->r_ctl.rc_map, rsm, r_next); 10357 TAILQ_INSERT_TAIL(&bbr->r_ctl.rc_tmap, rsm, r_tnext); 10358 rsm->r_in_tmap = 1; 10359 if (bbr->rc_bbr_state == BBR_STATE_PROBE_BW) 10360 rsm->r_bbr_state = bbr_state_val(bbr); 10361 else 10362 rsm->r_bbr_state = 8; 10363 } 10364 if (bbr_use_rack_resend_cheat && (bbr->rc_use_google == 0)) 10365 bbr->bbr_use_rack_cheat = 1; 10366 if (bbr_incr_timers && (bbr->rc_use_google == 0)) 10367 bbr->r_ctl.rc_incr_tmrs = 1; 10368 if (bbr_include_tcp_oh && (bbr->rc_use_google == 0)) 10369 bbr->r_ctl.rc_inc_tcp_oh = 1; 10370 if (bbr_include_ip_oh && (bbr->rc_use_google == 0)) 10371 bbr->r_ctl.rc_inc_ip_oh = 1; 10372 if (bbr_include_enet_oh && (bbr->rc_use_google == 0)) 10373 bbr->r_ctl.rc_inc_enet_oh = 1; 10374 10375 bbr_log_type_statechange(bbr, cts, __LINE__); 10376 if (TCPS_HAVEESTABLISHED(tp->t_state) && 10377 (tp->t_srtt)) { 10378 uint32_t rtt; 10379 10380 rtt = (TICKS_2_USEC(tp->t_srtt) >> TCP_RTT_SHIFT); 10381 apply_filter_min_small(&bbr->r_ctl.rc_rttprop, rtt, cts); 10382 } 10383 /* announce the settings and state */ 10384 bbr_log_settings_change(bbr, BBR_RECOVERY_LOWRTT); 10385 tcp_bbr_tso_size_check(bbr, cts); 10386 /* 10387 * Now call the generic function to start a timer. This will place 10388 * the TCB on the hptsi wheel if a timer is needed with appropriate 10389 * flags. 10390 */ 10391 bbr_stop_all_timers(tp); 10392 bbr_start_hpts_timer(bbr, tp, cts, 5, 0, 0); 10393 return (0); 10394 } 10395 10396 /* 10397 * Return 0 if we can accept the connection. Return 10398 * non-zero if we can't handle the connection. A EAGAIN 10399 * means you need to wait until the connection is up. 10400 * a EADDRNOTAVAIL means we can never handle the connection 10401 * (no SACK). 10402 */ 10403 static int 10404 bbr_handoff_ok(struct tcpcb *tp) 10405 { 10406 if ((tp->t_state == TCPS_CLOSED) || 10407 (tp->t_state == TCPS_LISTEN)) { 10408 /* Sure no problem though it may not stick */ 10409 return (0); 10410 } 10411 if ((tp->t_state == TCPS_SYN_SENT) || 10412 (tp->t_state == TCPS_SYN_RECEIVED)) { 10413 /* 10414 * We really don't know you have to get to ESTAB or beyond 10415 * to tell. 10416 */ 10417 return (EAGAIN); 10418 } 10419 if ((tp->t_flags & TF_SACK_PERMIT) || bbr_sack_not_required) { 10420 return (0); 10421 } 10422 /* 10423 * If we reach here we don't do SACK on this connection so we can 10424 * never do rack. 10425 */ 10426 return (EINVAL); 10427 } 10428 10429 static void 10430 bbr_fini(struct tcpcb *tp, int32_t tcb_is_purged) 10431 { 10432 if (tp->t_fb_ptr) { 10433 uint32_t calc; 10434 struct tcp_bbr *bbr; 10435 struct bbr_sendmap *rsm; 10436 10437 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 10438 if (bbr->r_ctl.crte) 10439 tcp_rel_pacing_rate(bbr->r_ctl.crte, bbr->rc_tp); 10440 bbr_log_flowend(bbr); 10441 bbr->rc_tp = NULL; 10442 if (tp->t_inpcb) { 10443 /* Backout any flags2 we applied */ 10444 tp->t_inpcb->inp_flags2 &= ~INP_CANNOT_DO_ECN; 10445 tp->t_inpcb->inp_flags2 &= ~INP_SUPPORTS_MBUFQ; 10446 tp->t_inpcb->inp_flags2 &= ~INP_MBUF_QUEUE_READY; 10447 } 10448 if (bbr->bbr_hdrw_pacing) 10449 counter_u64_add(bbr_flows_whdwr_pacing, -1); 10450 else 10451 counter_u64_add(bbr_flows_nohdwr_pacing, -1); 10452 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map); 10453 while (rsm) { 10454 TAILQ_REMOVE(&bbr->r_ctl.rc_map, rsm, r_next); 10455 uma_zfree(bbr_zone, rsm); 10456 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map); 10457 } 10458 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_free); 10459 while (rsm) { 10460 TAILQ_REMOVE(&bbr->r_ctl.rc_free, rsm, r_next); 10461 uma_zfree(bbr_zone, rsm); 10462 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_free); 10463 } 10464 calc = bbr->r_ctl.rc_high_rwnd - bbr->r_ctl.rc_init_rwnd; 10465 if (calc > (bbr->r_ctl.rc_init_rwnd / 10)) 10466 BBR_STAT_INC(bbr_dynamic_rwnd); 10467 else 10468 BBR_STAT_INC(bbr_static_rwnd); 10469 bbr->r_ctl.rc_free_cnt = 0; 10470 uma_zfree(bbr_pcb_zone, tp->t_fb_ptr); 10471 tp->t_fb_ptr = NULL; 10472 } 10473 /* Make sure snd_nxt is correctly set */ 10474 tp->snd_nxt = tp->snd_max; 10475 } 10476 10477 static void 10478 bbr_set_state(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t win) 10479 { 10480 switch (tp->t_state) { 10481 case TCPS_SYN_SENT: 10482 bbr->r_state = TCPS_SYN_SENT; 10483 bbr->r_substate = bbr_do_syn_sent; 10484 break; 10485 case TCPS_SYN_RECEIVED: 10486 bbr->r_state = TCPS_SYN_RECEIVED; 10487 bbr->r_substate = bbr_do_syn_recv; 10488 break; 10489 case TCPS_ESTABLISHED: 10490 bbr->r_ctl.rc_init_rwnd = max(win, bbr->rc_tp->snd_wnd); 10491 bbr->r_state = TCPS_ESTABLISHED; 10492 bbr->r_substate = bbr_do_established; 10493 break; 10494 case TCPS_CLOSE_WAIT: 10495 bbr->r_state = TCPS_CLOSE_WAIT; 10496 bbr->r_substate = bbr_do_close_wait; 10497 break; 10498 case TCPS_FIN_WAIT_1: 10499 bbr->r_state = TCPS_FIN_WAIT_1; 10500 bbr->r_substate = bbr_do_fin_wait_1; 10501 break; 10502 case TCPS_CLOSING: 10503 bbr->r_state = TCPS_CLOSING; 10504 bbr->r_substate = bbr_do_closing; 10505 break; 10506 case TCPS_LAST_ACK: 10507 bbr->r_state = TCPS_LAST_ACK; 10508 bbr->r_substate = bbr_do_lastack; 10509 break; 10510 case TCPS_FIN_WAIT_2: 10511 bbr->r_state = TCPS_FIN_WAIT_2; 10512 bbr->r_substate = bbr_do_fin_wait_2; 10513 break; 10514 case TCPS_LISTEN: 10515 case TCPS_CLOSED: 10516 case TCPS_TIME_WAIT: 10517 default: 10518 break; 10519 }; 10520 } 10521 10522 static void 10523 bbr_substate_change(struct tcp_bbr *bbr, uint32_t cts, int32_t line, int dolog) 10524 { 10525 /* 10526 * Now what state are we going into now? Is there adjustments 10527 * needed? 10528 */ 10529 int32_t old_state, old_gain; 10530 10531 10532 old_state = bbr_state_val(bbr); 10533 old_gain = bbr->r_ctl.rc_bbr_hptsi_gain; 10534 if (bbr_state_val(bbr) == BBR_SUB_LEVEL1) { 10535 /* Save the lowest srtt we saw in our end of the sub-state */ 10536 bbr->rc_hit_state_1 = 0; 10537 if (bbr->r_ctl.bbr_smallest_srtt_this_state != 0xffffffff) 10538 bbr->r_ctl.bbr_smallest_srtt_state2 = bbr->r_ctl.bbr_smallest_srtt_this_state; 10539 } 10540 bbr->rc_bbr_substate++; 10541 if (bbr->rc_bbr_substate >= BBR_SUBSTATE_COUNT) { 10542 /* Cycle back to first state-> gain */ 10543 bbr->rc_bbr_substate = 0; 10544 } 10545 if (bbr_state_val(bbr) == BBR_SUB_GAIN) { 10546 /* 10547 * We enter the gain(5/4) cycle (possibly less if 10548 * shallow buffer detection is enabled) 10549 */ 10550 if (bbr->skip_gain) { 10551 /* 10552 * Hardware pacing has set our rate to 10553 * the max and limited our b/w just 10554 * do level i.e. no gain. 10555 */ 10556 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_hptsi_gain[BBR_SUB_LEVEL1]; 10557 } else if (bbr->gain_is_limited && 10558 bbr->bbr_hdrw_pacing && 10559 bbr->r_ctl.crte) { 10560 /* 10561 * We can't gain above the hardware pacing 10562 * rate which is less than our rate + the gain 10563 * calculate the gain needed to reach the hardware 10564 * pacing rate.. 10565 */ 10566 uint64_t bw, rate, gain_calc; 10567 10568 bw = bbr_get_bw(bbr); 10569 rate = bbr->r_ctl.crte->rate; 10570 if ((rate > bw) && 10571 (((bw * (uint64_t)bbr_hptsi_gain[BBR_SUB_GAIN]) / (uint64_t)BBR_UNIT) > rate)) { 10572 gain_calc = (rate * BBR_UNIT) / bw; 10573 if (gain_calc < BBR_UNIT) 10574 gain_calc = BBR_UNIT; 10575 bbr->r_ctl.rc_bbr_hptsi_gain = (uint16_t)gain_calc; 10576 } else { 10577 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_hptsi_gain[BBR_SUB_GAIN]; 10578 } 10579 } else 10580 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_hptsi_gain[BBR_SUB_GAIN]; 10581 if ((bbr->rc_use_google == 0) && (bbr_gain_to_target == 0)) { 10582 bbr->r_ctl.rc_bbr_state_atflight = cts; 10583 } else 10584 bbr->r_ctl.rc_bbr_state_atflight = 0; 10585 } else if (bbr_state_val(bbr) == BBR_SUB_DRAIN) { 10586 bbr->rc_hit_state_1 = 1; 10587 bbr->r_ctl.rc_exta_time_gd = 0; 10588 bbr->r_ctl.flightsize_at_drain = ctf_flight_size(bbr->rc_tp, 10589 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 10590 if (bbr_state_drain_2_tar) { 10591 bbr->r_ctl.rc_bbr_state_atflight = 0; 10592 } else 10593 bbr->r_ctl.rc_bbr_state_atflight = cts; 10594 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_hptsi_gain[BBR_SUB_DRAIN]; 10595 } else { 10596 /* All other cycles hit here 2-7 */ 10597 if ((old_state == BBR_SUB_DRAIN) && bbr->rc_hit_state_1) { 10598 if (bbr_sub_drain_slam_cwnd && 10599 (bbr->rc_use_google == 0) && 10600 (bbr->rc_tp->snd_cwnd < bbr->r_ctl.rc_saved_cwnd)) { 10601 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_saved_cwnd; 10602 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 10603 } 10604 if ((cts - bbr->r_ctl.rc_bbr_state_time) > bbr_get_rtt(bbr, BBR_RTT_PROP)) 10605 bbr->r_ctl.rc_exta_time_gd += ((cts - bbr->r_ctl.rc_bbr_state_time) - 10606 bbr_get_rtt(bbr, BBR_RTT_PROP)); 10607 else 10608 bbr->r_ctl.rc_exta_time_gd = 0; 10609 if (bbr->r_ctl.rc_exta_time_gd) { 10610 bbr->r_ctl.rc_level_state_extra = bbr->r_ctl.rc_exta_time_gd; 10611 /* Now chop up the time for each state (div by 7) */ 10612 bbr->r_ctl.rc_level_state_extra /= 7; 10613 if (bbr_rand_ot && bbr->r_ctl.rc_level_state_extra) { 10614 /* Add a randomization */ 10615 bbr_randomize_extra_state_time(bbr); 10616 } 10617 } 10618 } 10619 bbr->r_ctl.rc_bbr_state_atflight = max(1, cts); 10620 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_hptsi_gain[bbr_state_val(bbr)]; 10621 } 10622 if (bbr->rc_use_google) { 10623 bbr->r_ctl.rc_bbr_state_atflight = max(1, cts); 10624 } 10625 bbr->r_ctl.bbr_lost_at_state = bbr->r_ctl.rc_lost; 10626 bbr->r_ctl.rc_bbr_cwnd_gain = bbr_cwnd_gain; 10627 if (dolog) 10628 bbr_log_type_statechange(bbr, cts, line); 10629 10630 if (SEQ_GT(cts, bbr->r_ctl.rc_bbr_state_time)) { 10631 uint32_t time_in; 10632 10633 time_in = cts - bbr->r_ctl.rc_bbr_state_time; 10634 if (bbr->rc_bbr_state == BBR_STATE_PROBE_BW) { 10635 counter_u64_add(bbr_state_time[(old_state + 5)], time_in); 10636 } else { 10637 counter_u64_add(bbr_state_time[bbr->rc_bbr_state], time_in); 10638 } 10639 } 10640 bbr->r_ctl.bbr_smallest_srtt_this_state = 0xffffffff; 10641 bbr_set_state_target(bbr, __LINE__); 10642 if (bbr_sub_drain_slam_cwnd && 10643 (bbr->rc_use_google == 0) && 10644 (bbr_state_val(bbr) == BBR_SUB_DRAIN)) { 10645 /* Slam down the cwnd */ 10646 bbr->r_ctl.rc_saved_cwnd = bbr->rc_tp->snd_cwnd; 10647 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_target_at_state; 10648 if (bbr_sub_drain_app_limit) { 10649 /* Go app limited if we are on a long drain */ 10650 bbr->r_ctl.r_app_limited_until = (bbr->r_ctl.rc_delivered + 10651 ctf_flight_size(bbr->rc_tp, 10652 (bbr->r_ctl.rc_sacked + 10653 bbr->r_ctl.rc_lost_bytes))); 10654 } 10655 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 10656 } 10657 if (bbr->rc_lt_use_bw) { 10658 /* In policed mode we clamp pacing_gain to BBR_UNIT */ 10659 bbr->r_ctl.rc_bbr_hptsi_gain = BBR_UNIT; 10660 } 10661 /* Google changes TSO size every cycle */ 10662 if (bbr->rc_use_google) 10663 tcp_bbr_tso_size_check(bbr, cts); 10664 bbr->r_ctl.gain_epoch = cts; 10665 bbr->r_ctl.rc_bbr_state_time = cts; 10666 bbr->r_ctl.substate_pe = bbr->r_ctl.rc_pkt_epoch; 10667 } 10668 10669 static void 10670 bbr_set_probebw_google_gains(struct tcp_bbr *bbr, uint32_t cts, uint32_t losses) 10671 { 10672 if ((bbr_state_val(bbr) == BBR_SUB_DRAIN) && 10673 (google_allow_early_out == 1) && 10674 (bbr->r_ctl.rc_flight_at_input <= bbr->r_ctl.rc_target_at_state)) { 10675 /* We have reached out target flight size possibly early */ 10676 goto change_state; 10677 } 10678 if (TSTMP_LT(cts, bbr->r_ctl.rc_bbr_state_time)) { 10679 return; 10680 } 10681 if ((cts - bbr->r_ctl.rc_bbr_state_time) < bbr_get_rtt(bbr, BBR_RTT_PROP)) { 10682 /* 10683 * Must be a rttProp movement forward before 10684 * we can change states. 10685 */ 10686 return; 10687 } 10688 if (bbr_state_val(bbr) == BBR_SUB_GAIN) { 10689 /* 10690 * The needed time has passed but for 10691 * the gain cycle extra rules apply: 10692 * 1) If we have seen loss, we exit 10693 * 2) If we have not reached the target 10694 * we stay in GAIN (gain-to-target). 10695 */ 10696 if (google_consider_lost && losses) 10697 goto change_state; 10698 if (bbr->r_ctl.rc_target_at_state > bbr->r_ctl.rc_flight_at_input) { 10699 return; 10700 } 10701 } 10702 change_state: 10703 /* For gain we must reach our target, all others last 1 rttProp */ 10704 bbr_substate_change(bbr, cts, __LINE__, 1); 10705 } 10706 10707 static void 10708 bbr_set_probebw_gains(struct tcp_bbr *bbr, uint32_t cts, uint32_t losses) 10709 { 10710 uint32_t flight, bbr_cur_cycle_time; 10711 10712 if (bbr->rc_use_google) { 10713 bbr_set_probebw_google_gains(bbr, cts, losses); 10714 return; 10715 } 10716 if (cts == 0) { 10717 /* 10718 * Never alow cts to be 0 we 10719 * do this so we can judge if 10720 * we have set a timestamp. 10721 */ 10722 cts = 1; 10723 } 10724 if (bbr_state_is_pkt_epoch) 10725 bbr_cur_cycle_time = bbr_get_rtt(bbr, BBR_RTT_PKTRTT); 10726 else 10727 bbr_cur_cycle_time = bbr_get_rtt(bbr, BBR_RTT_PROP); 10728 10729 if (bbr->r_ctl.rc_bbr_state_atflight == 0) { 10730 if (bbr_state_val(bbr) == BBR_SUB_DRAIN) { 10731 flight = ctf_flight_size(bbr->rc_tp, 10732 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 10733 if (bbr_sub_drain_slam_cwnd && bbr->rc_hit_state_1) { 10734 /* Keep it slam down */ 10735 if (bbr->rc_tp->snd_cwnd > bbr->r_ctl.rc_target_at_state) { 10736 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_target_at_state; 10737 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 10738 } 10739 if (bbr_sub_drain_app_limit) { 10740 /* Go app limited if we are on a long drain */ 10741 bbr->r_ctl.r_app_limited_until = (bbr->r_ctl.rc_delivered + flight); 10742 } 10743 } 10744 if (TSTMP_GT(cts, bbr->r_ctl.gain_epoch) && 10745 (((cts - bbr->r_ctl.gain_epoch) > bbr_get_rtt(bbr, BBR_RTT_PROP)) || 10746 (flight >= bbr->r_ctl.flightsize_at_drain))) { 10747 /* 10748 * Still here after the same time as 10749 * the gain. We need to drain harder 10750 * for the next srtt. Reduce by a set amount 10751 * the gain drop is capped at DRAIN states 10752 * value (88). 10753 */ 10754 bbr->r_ctl.flightsize_at_drain = flight; 10755 if (bbr_drain_drop_mul && 10756 bbr_drain_drop_div && 10757 (bbr_drain_drop_mul < bbr_drain_drop_div)) { 10758 /* Use your specific drop value (def 4/5 = 20%) */ 10759 bbr->r_ctl.rc_bbr_hptsi_gain *= bbr_drain_drop_mul; 10760 bbr->r_ctl.rc_bbr_hptsi_gain /= bbr_drain_drop_div; 10761 } else { 10762 /* You get drop of 20% */ 10763 bbr->r_ctl.rc_bbr_hptsi_gain *= 4; 10764 bbr->r_ctl.rc_bbr_hptsi_gain /= 5; 10765 } 10766 if (bbr->r_ctl.rc_bbr_hptsi_gain <= bbr_drain_floor) { 10767 /* Reduce our gain again to the bottom */ 10768 bbr->r_ctl.rc_bbr_hptsi_gain = max(bbr_drain_floor, 1); 10769 } 10770 bbr_log_exit_gain(bbr, cts, 4); 10771 /* 10772 * Extend out so we wait another 10773 * epoch before dropping again. 10774 */ 10775 bbr->r_ctl.gain_epoch = cts; 10776 } 10777 if (flight <= bbr->r_ctl.rc_target_at_state) { 10778 if (bbr_sub_drain_slam_cwnd && 10779 (bbr->rc_use_google == 0) && 10780 (bbr->rc_tp->snd_cwnd < bbr->r_ctl.rc_saved_cwnd)) { 10781 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_saved_cwnd; 10782 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 10783 } 10784 bbr->r_ctl.rc_bbr_state_atflight = max(cts, 1); 10785 bbr_log_exit_gain(bbr, cts, 3); 10786 } 10787 } else { 10788 /* Its a gain */ 10789 if (bbr->r_ctl.rc_lost > bbr->r_ctl.bbr_lost_at_state) { 10790 bbr->r_ctl.rc_bbr_state_atflight = max(cts, 1); 10791 goto change_state; 10792 } 10793 if ((ctf_outstanding(bbr->rc_tp) >= bbr->r_ctl.rc_target_at_state) || 10794 ((ctf_outstanding(bbr->rc_tp) + bbr->rc_tp->t_maxseg - 1) >= 10795 bbr->rc_tp->snd_wnd)) { 10796 bbr->r_ctl.rc_bbr_state_atflight = max(cts, 1); 10797 bbr_log_exit_gain(bbr, cts, 2); 10798 } 10799 } 10800 /** 10801 * We fall through and return always one of two things has 10802 * occured. 10803 * 1) We are still not at target 10804 * <or> 10805 * 2) We reached the target and set rc_bbr_state_atflight 10806 * which means we no longer hit this block 10807 * next time we are called. 10808 */ 10809 return; 10810 } 10811 change_state: 10812 if (TSTMP_LT(cts, bbr->r_ctl.rc_bbr_state_time)) 10813 return; 10814 if ((cts - bbr->r_ctl.rc_bbr_state_time) < bbr_cur_cycle_time) { 10815 /* Less than a full time-period has passed */ 10816 return; 10817 } 10818 if (bbr->r_ctl.rc_level_state_extra && 10819 (bbr_state_val(bbr) > BBR_SUB_DRAIN) && 10820 ((cts - bbr->r_ctl.rc_bbr_state_time) < 10821 (bbr_cur_cycle_time + bbr->r_ctl.rc_level_state_extra))) { 10822 /* Less than a full time-period + extra has passed */ 10823 return; 10824 } 10825 if (bbr_gain_gets_extra_too && 10826 bbr->r_ctl.rc_level_state_extra && 10827 (bbr_state_val(bbr) == BBR_SUB_GAIN) && 10828 ((cts - bbr->r_ctl.rc_bbr_state_time) < 10829 (bbr_cur_cycle_time + bbr->r_ctl.rc_level_state_extra))) { 10830 /* Less than a full time-period + extra has passed */ 10831 return; 10832 } 10833 bbr_substate_change(bbr, cts, __LINE__, 1); 10834 } 10835 10836 static uint32_t 10837 bbr_get_a_state_target(struct tcp_bbr *bbr, uint32_t gain) 10838 { 10839 uint32_t mss, tar; 10840 10841 if (bbr->rc_use_google) { 10842 /* Google just uses the cwnd target */ 10843 tar = bbr_get_target_cwnd(bbr, bbr_get_bw(bbr), gain); 10844 } else { 10845 mss = min((bbr->rc_tp->t_maxseg - bbr->rc_last_options), 10846 bbr->r_ctl.rc_pace_max_segs); 10847 /* Get the base cwnd with gain rounded to a mss */ 10848 tar = roundup(bbr_get_raw_target_cwnd(bbr, bbr_get_bw(bbr), 10849 gain), mss); 10850 /* Make sure it is within our min */ 10851 if (tar < get_min_cwnd(bbr)) 10852 return (get_min_cwnd(bbr)); 10853 } 10854 return (tar); 10855 } 10856 10857 static void 10858 bbr_set_state_target(struct tcp_bbr *bbr, int line) 10859 { 10860 uint32_t tar, meth; 10861 10862 if ((bbr->rc_bbr_state == BBR_STATE_PROBE_RTT) && 10863 ((bbr->r_ctl.bbr_rttprobe_gain_val == 0) || bbr->rc_use_google)) { 10864 /* Special case using old probe-rtt method */ 10865 tar = bbr_rtt_probe_cwndtarg * (bbr->rc_tp->t_maxseg - bbr->rc_last_options); 10866 meth = 1; 10867 } else { 10868 /* Non-probe-rtt case and reduced probe-rtt */ 10869 if ((bbr->rc_bbr_state == BBR_STATE_PROBE_BW) && 10870 (bbr->r_ctl.rc_bbr_hptsi_gain > BBR_UNIT)) { 10871 /* For gain cycle we use the hptsi gain */ 10872 tar = bbr_get_a_state_target(bbr, bbr->r_ctl.rc_bbr_hptsi_gain); 10873 meth = 2; 10874 } else if ((bbr_target_is_bbunit) || bbr->rc_use_google) { 10875 /* 10876 * If configured, or for google all other states 10877 * get BBR_UNIT. 10878 */ 10879 tar = bbr_get_a_state_target(bbr, BBR_UNIT); 10880 meth = 3; 10881 } else { 10882 /* 10883 * Or we set a target based on the pacing gain 10884 * for non-google mode and default (non-configured). 10885 * Note we don't set a target goal below drain (192). 10886 */ 10887 if (bbr->r_ctl.rc_bbr_hptsi_gain < bbr_hptsi_gain[BBR_SUB_DRAIN]) { 10888 tar = bbr_get_a_state_target(bbr, bbr_hptsi_gain[BBR_SUB_DRAIN]); 10889 meth = 4; 10890 } else { 10891 tar = bbr_get_a_state_target(bbr, bbr->r_ctl.rc_bbr_hptsi_gain); 10892 meth = 5; 10893 } 10894 } 10895 } 10896 bbr_log_set_of_state_target(bbr, tar, line, meth); 10897 bbr->r_ctl.rc_target_at_state = tar; 10898 } 10899 10900 static void 10901 bbr_enter_probe_rtt(struct tcp_bbr *bbr, uint32_t cts, int32_t line) 10902 { 10903 /* Change to probe_rtt */ 10904 uint32_t time_in; 10905 10906 bbr->r_ctl.bbr_lost_at_state = bbr->r_ctl.rc_lost; 10907 bbr->r_ctl.flightsize_at_drain = ctf_flight_size(bbr->rc_tp, 10908 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 10909 bbr->r_ctl.r_app_limited_until = (bbr->r_ctl.flightsize_at_drain 10910 + bbr->r_ctl.rc_delivered); 10911 /* Setup so we force feed the filter */ 10912 if (bbr->rc_use_google || bbr_probertt_sets_rtt) 10913 bbr->rc_prtt_set_ts = 1; 10914 if (SEQ_GT(cts, bbr->r_ctl.rc_bbr_state_time)) { 10915 time_in = cts - bbr->r_ctl.rc_bbr_state_time; 10916 counter_u64_add(bbr_state_time[bbr->rc_bbr_state], time_in); 10917 } 10918 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_ENTERPROBE, 0); 10919 bbr->r_ctl.rc_rtt_shrinks = cts; 10920 bbr->r_ctl.last_in_probertt = cts; 10921 bbr->r_ctl.rc_probertt_srttchktim = cts; 10922 bbr->r_ctl.rc_bbr_state_time = cts; 10923 bbr->rc_bbr_state = BBR_STATE_PROBE_RTT; 10924 /* We need to force the filter to update */ 10925 10926 if ((bbr_sub_drain_slam_cwnd) && 10927 bbr->rc_hit_state_1 && 10928 (bbr->rc_use_google == 0) && 10929 (bbr_state_val(bbr) == BBR_SUB_DRAIN)) { 10930 if (bbr->rc_tp->snd_cwnd > bbr->r_ctl.rc_saved_cwnd) 10931 bbr->r_ctl.rc_saved_cwnd = bbr->rc_tp->snd_cwnd; 10932 } else 10933 bbr->r_ctl.rc_saved_cwnd = bbr->rc_tp->snd_cwnd; 10934 /* Update the lost */ 10935 bbr->r_ctl.rc_lost_at_startup = bbr->r_ctl.rc_lost; 10936 if ((bbr->r_ctl.bbr_rttprobe_gain_val == 0) || bbr->rc_use_google){ 10937 /* Set to the non-configurable default of 4 (PROBE_RTT_MIN) */ 10938 bbr->rc_tp->snd_cwnd = bbr_rtt_probe_cwndtarg * (bbr->rc_tp->t_maxseg - bbr->rc_last_options); 10939 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 10940 bbr->r_ctl.rc_bbr_hptsi_gain = BBR_UNIT; 10941 bbr->r_ctl.rc_bbr_cwnd_gain = BBR_UNIT; 10942 bbr_log_set_of_state_target(bbr, bbr->rc_tp->snd_cwnd, __LINE__, 6); 10943 bbr->r_ctl.rc_target_at_state = bbr->rc_tp->snd_cwnd; 10944 } else { 10945 /* 10946 * We bring it down slowly by using a hptsi gain that is 10947 * probably 75%. This will slowly float down our outstanding 10948 * without tampering with the cwnd. 10949 */ 10950 bbr->r_ctl.rc_bbr_hptsi_gain = bbr->r_ctl.bbr_rttprobe_gain_val; 10951 bbr->r_ctl.rc_bbr_cwnd_gain = BBR_UNIT; 10952 bbr_set_state_target(bbr, __LINE__); 10953 if (bbr_prtt_slam_cwnd && 10954 (bbr->rc_tp->snd_cwnd > bbr->r_ctl.rc_target_at_state)) { 10955 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_target_at_state; 10956 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 10957 } 10958 } 10959 if (ctf_flight_size(bbr->rc_tp, 10960 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)) <= 10961 bbr->r_ctl.rc_target_at_state) { 10962 /* We are at target */ 10963 bbr->r_ctl.rc_bbr_enters_probertt = cts; 10964 } else { 10965 /* We need to come down to reach target before our time begins */ 10966 bbr->r_ctl.rc_bbr_enters_probertt = 0; 10967 } 10968 bbr->r_ctl.rc_pe_of_prtt = bbr->r_ctl.rc_pkt_epoch; 10969 BBR_STAT_INC(bbr_enter_probertt); 10970 bbr_log_exit_gain(bbr, cts, 0); 10971 bbr_log_type_statechange(bbr, cts, line); 10972 } 10973 10974 static void 10975 bbr_check_probe_rtt_limits(struct tcp_bbr *bbr, uint32_t cts) 10976 { 10977 /* 10978 * Sanity check on probe-rtt intervals. 10979 * In crazy situations where we are competing 10980 * against new-reno flows with huge buffers 10981 * our rtt-prop interval could come to dominate 10982 * things if we can't get through a full set 10983 * of cycles, we need to adjust it. 10984 */ 10985 if (bbr_can_adjust_probertt && 10986 (bbr->rc_use_google == 0)) { 10987 uint16_t val = 0; 10988 uint32_t cur_rttp, fval, newval, baseval; 10989 10990 /* Are we to small and go into probe-rtt to often? */ 10991 baseval = (bbr_get_rtt(bbr, BBR_RTT_PROP) * (BBR_SUBSTATE_COUNT + 1)); 10992 cur_rttp = roundup(baseval, USECS_IN_SECOND); 10993 fval = bbr_filter_len_sec * USECS_IN_SECOND; 10994 if (bbr_is_ratio == 0) { 10995 if (fval > bbr_rtt_probe_limit) 10996 newval = cur_rttp + (fval - bbr_rtt_probe_limit); 10997 else 10998 newval = cur_rttp; 10999 } else { 11000 int mul; 11001 11002 mul = fval / bbr_rtt_probe_limit; 11003 newval = cur_rttp * mul; 11004 } 11005 if (cur_rttp > bbr->r_ctl.rc_probertt_int) { 11006 bbr->r_ctl.rc_probertt_int = cur_rttp; 11007 reset_time_small(&bbr->r_ctl.rc_rttprop, newval); 11008 val = 1; 11009 } else { 11010 /* 11011 * No adjustments were made 11012 * do we need to shrink it? 11013 */ 11014 if (bbr->r_ctl.rc_probertt_int > bbr_rtt_probe_limit) { 11015 if (cur_rttp <= bbr_rtt_probe_limit) { 11016 /* 11017 * Things have calmed down lets 11018 * shrink all the way to default 11019 */ 11020 bbr->r_ctl.rc_probertt_int = bbr_rtt_probe_limit; 11021 reset_time_small(&bbr->r_ctl.rc_rttprop, 11022 (bbr_filter_len_sec * USECS_IN_SECOND)); 11023 cur_rttp = bbr_rtt_probe_limit; 11024 newval = (bbr_filter_len_sec * USECS_IN_SECOND); 11025 val = 2; 11026 } else { 11027 /* 11028 * Well does some adjustment make sense? 11029 */ 11030 if (cur_rttp < bbr->r_ctl.rc_probertt_int) { 11031 /* We can reduce interval time some */ 11032 bbr->r_ctl.rc_probertt_int = cur_rttp; 11033 reset_time_small(&bbr->r_ctl.rc_rttprop, newval); 11034 val = 3; 11035 } 11036 } 11037 } 11038 } 11039 if (val) 11040 bbr_log_rtt_shrinks(bbr, cts, cur_rttp, newval, __LINE__, BBR_RTTS_RESETS_VALUES, val); 11041 } 11042 } 11043 11044 static void 11045 bbr_exit_probe_rtt(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts) 11046 { 11047 /* Exit probe-rtt */ 11048 11049 if (tp->snd_cwnd < bbr->r_ctl.rc_saved_cwnd) { 11050 tp->snd_cwnd = bbr->r_ctl.rc_saved_cwnd; 11051 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 11052 } 11053 bbr_log_exit_gain(bbr, cts, 1); 11054 bbr->rc_hit_state_1 = 0; 11055 bbr->r_ctl.rc_rtt_shrinks = cts; 11056 bbr->r_ctl.last_in_probertt = cts; 11057 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_RTTPROBE, 0); 11058 bbr->r_ctl.bbr_lost_at_state = bbr->r_ctl.rc_lost; 11059 bbr->r_ctl.r_app_limited_until = (ctf_flight_size(tp, 11060 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)) + 11061 bbr->r_ctl.rc_delivered); 11062 if (SEQ_GT(cts, bbr->r_ctl.rc_bbr_state_time)) { 11063 uint32_t time_in; 11064 11065 time_in = cts - bbr->r_ctl.rc_bbr_state_time; 11066 counter_u64_add(bbr_state_time[bbr->rc_bbr_state], time_in); 11067 } 11068 if (bbr->rc_filled_pipe) { 11069 /* Switch to probe_bw */ 11070 bbr->rc_bbr_state = BBR_STATE_PROBE_BW; 11071 bbr->rc_bbr_substate = bbr_pick_probebw_substate(bbr, cts); 11072 bbr->r_ctl.rc_bbr_cwnd_gain = bbr_cwnd_gain; 11073 bbr_substate_change(bbr, cts, __LINE__, 0); 11074 bbr_log_type_statechange(bbr, cts, __LINE__); 11075 } else { 11076 /* Back to startup */ 11077 bbr->rc_bbr_state = BBR_STATE_STARTUP; 11078 bbr->r_ctl.rc_bbr_state_time = cts; 11079 /* 11080 * We don't want to give a complete free 3 11081 * measurements until we exit, so we use 11082 * the number of pe's we were in probe-rtt 11083 * to add to the startup_epoch. That way 11084 * we will still retain the old state. 11085 */ 11086 bbr->r_ctl.rc_bbr_last_startup_epoch += (bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_pe_of_prtt); 11087 bbr->r_ctl.rc_lost_at_startup = bbr->r_ctl.rc_lost; 11088 /* Make sure to use the lower pg when shifting back in */ 11089 if (bbr->r_ctl.rc_lost && 11090 bbr_use_lower_gain_in_startup && 11091 (bbr->rc_use_google == 0)) 11092 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_startup_lower; 11093 else 11094 bbr->r_ctl.rc_bbr_hptsi_gain = bbr->r_ctl.rc_startup_pg; 11095 bbr->r_ctl.rc_bbr_cwnd_gain = bbr->r_ctl.rc_startup_pg; 11096 /* Probably not needed but set it anyway */ 11097 bbr_set_state_target(bbr, __LINE__); 11098 bbr_log_type_statechange(bbr, cts, __LINE__); 11099 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch, 11100 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 0); 11101 } 11102 bbr_check_probe_rtt_limits(bbr, cts); 11103 } 11104 11105 static int32_t inline 11106 bbr_should_enter_probe_rtt(struct tcp_bbr *bbr, uint32_t cts) 11107 { 11108 if ((bbr->rc_past_init_win == 1) && 11109 (bbr->rc_in_persist == 0) && 11110 (bbr_calc_time(cts, bbr->r_ctl.rc_rtt_shrinks) >= bbr->r_ctl.rc_probertt_int)) { 11111 return (1); 11112 } 11113 if (bbr_can_force_probertt && 11114 (bbr->rc_in_persist == 0) && 11115 (TSTMP_GT(cts, bbr->r_ctl.last_in_probertt)) && 11116 ((cts - bbr->r_ctl.last_in_probertt) > bbr->r_ctl.rc_probertt_int)) { 11117 return (1); 11118 } 11119 return (0); 11120 } 11121 11122 11123 static int32_t 11124 bbr_google_startup(struct tcp_bbr *bbr, uint32_t cts, int32_t pkt_epoch) 11125 { 11126 uint64_t btlbw, gain; 11127 if (pkt_epoch == 0) { 11128 /* 11129 * Need to be on a pkt-epoch to continue. 11130 */ 11131 return (0); 11132 } 11133 btlbw = bbr_get_full_bw(bbr); 11134 gain = ((bbr->r_ctl.rc_bbr_lastbtlbw * 11135 (uint64_t)bbr_start_exit) / (uint64_t)100) + bbr->r_ctl.rc_bbr_lastbtlbw; 11136 if (btlbw >= gain) { 11137 bbr->r_ctl.rc_bbr_last_startup_epoch = bbr->r_ctl.rc_pkt_epoch; 11138 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch, 11139 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 3); 11140 bbr->r_ctl.rc_bbr_lastbtlbw = btlbw; 11141 } 11142 if ((bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_bbr_last_startup_epoch) >= BBR_STARTUP_EPOCHS) 11143 return (1); 11144 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch, 11145 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 8); 11146 return(0); 11147 } 11148 11149 static int32_t inline 11150 bbr_state_startup(struct tcp_bbr *bbr, uint32_t cts, int32_t epoch, int32_t pkt_epoch) 11151 { 11152 /* Have we gained 25% in the last 3 packet based epoch's? */ 11153 uint64_t btlbw, gain; 11154 int do_exit; 11155 int delta, rtt_gain; 11156 11157 if ((bbr->rc_tp->snd_una == bbr->rc_tp->snd_max) && 11158 (bbr_calc_time(cts, bbr->r_ctl.rc_went_idle_time) >= bbr_rtt_probe_time)) { 11159 /* 11160 * This qualifies as a RTT_PROBE session since we drop the 11161 * data outstanding to nothing and waited more than 11162 * bbr_rtt_probe_time. 11163 */ 11164 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_WASIDLE, 0); 11165 bbr_set_reduced_rtt(bbr, cts, __LINE__); 11166 } 11167 if (bbr_should_enter_probe_rtt(bbr, cts)) { 11168 bbr_enter_probe_rtt(bbr, cts, __LINE__); 11169 return (0); 11170 } 11171 if (bbr->rc_use_google) 11172 return (bbr_google_startup(bbr, cts, pkt_epoch)); 11173 11174 if ((bbr->r_ctl.rc_lost > bbr->r_ctl.rc_lost_at_startup) && 11175 (bbr_use_lower_gain_in_startup)) { 11176 /* Drop to a lower gain 1.5 x since we saw loss */ 11177 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_startup_lower; 11178 } 11179 if (pkt_epoch == 0) { 11180 /* 11181 * Need to be on a pkt-epoch to continue. 11182 */ 11183 return (0); 11184 } 11185 if (bbr_rtt_gain_thresh) { 11186 /* 11187 * Do we allow a flow to stay 11188 * in startup with no loss and no 11189 * gain in rtt over a set threshold? 11190 */ 11191 if (bbr->r_ctl.rc_pkt_epoch_rtt && 11192 bbr->r_ctl.startup_last_srtt && 11193 (bbr->r_ctl.rc_pkt_epoch_rtt > bbr->r_ctl.startup_last_srtt)) { 11194 delta = bbr->r_ctl.rc_pkt_epoch_rtt - bbr->r_ctl.startup_last_srtt; 11195 rtt_gain = (delta * 100) / bbr->r_ctl.startup_last_srtt; 11196 } else 11197 rtt_gain = 0; 11198 if ((bbr->r_ctl.startup_last_srtt == 0) || 11199 (bbr->r_ctl.rc_pkt_epoch_rtt < bbr->r_ctl.startup_last_srtt)) 11200 /* First time or new lower value */ 11201 bbr->r_ctl.startup_last_srtt = bbr->r_ctl.rc_pkt_epoch_rtt; 11202 11203 if ((bbr->r_ctl.rc_lost == 0) && 11204 (rtt_gain < bbr_rtt_gain_thresh)) { 11205 /* 11206 * No loss, and we are under 11207 * our gain threhold for 11208 * increasing RTT. 11209 */ 11210 if (bbr->r_ctl.rc_bbr_last_startup_epoch < bbr->r_ctl.rc_pkt_epoch) 11211 bbr->r_ctl.rc_bbr_last_startup_epoch++; 11212 bbr_log_startup_event(bbr, cts, rtt_gain, 11213 delta, bbr->r_ctl.startup_last_srtt, 10); 11214 return (0); 11215 } 11216 } 11217 if ((bbr->r_ctl.r_measurement_count == bbr->r_ctl.last_startup_measure) && 11218 (bbr->r_ctl.rc_lost_at_startup == bbr->r_ctl.rc_lost) && 11219 (!IN_RECOVERY(bbr->rc_tp->t_flags))) { 11220 /* 11221 * We only assess if we have a new measurment when 11222 * we have no loss and are not in recovery. 11223 * Drag up by one our last_startup epoch so we will hold 11224 * the number of non-gain we have already accumulated. 11225 */ 11226 if (bbr->r_ctl.rc_bbr_last_startup_epoch < bbr->r_ctl.rc_pkt_epoch) 11227 bbr->r_ctl.rc_bbr_last_startup_epoch++; 11228 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch, 11229 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 9); 11230 return (0); 11231 } 11232 /* Case where we reduced the lost (bad retransmit) */ 11233 if (bbr->r_ctl.rc_lost_at_startup > bbr->r_ctl.rc_lost) 11234 bbr->r_ctl.rc_lost_at_startup = bbr->r_ctl.rc_lost; 11235 bbr->r_ctl.last_startup_measure = bbr->r_ctl.r_measurement_count; 11236 btlbw = bbr_get_full_bw(bbr); 11237 if (bbr->r_ctl.rc_bbr_hptsi_gain == bbr_startup_lower) 11238 gain = ((bbr->r_ctl.rc_bbr_lastbtlbw * 11239 (uint64_t)bbr_low_start_exit) / (uint64_t)100) + bbr->r_ctl.rc_bbr_lastbtlbw; 11240 else 11241 gain = ((bbr->r_ctl.rc_bbr_lastbtlbw * 11242 (uint64_t)bbr_start_exit) / (uint64_t)100) + bbr->r_ctl.rc_bbr_lastbtlbw; 11243 do_exit = 0; 11244 if (btlbw > bbr->r_ctl.rc_bbr_lastbtlbw) 11245 bbr->r_ctl.rc_bbr_lastbtlbw = btlbw; 11246 if (btlbw >= gain) { 11247 bbr->r_ctl.rc_bbr_last_startup_epoch = bbr->r_ctl.rc_pkt_epoch; 11248 /* Update the lost so we won't exit in next set of tests */ 11249 bbr->r_ctl.rc_lost_at_startup = bbr->r_ctl.rc_lost; 11250 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch, 11251 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 3); 11252 } 11253 if ((bbr->rc_loss_exit && 11254 (bbr->r_ctl.rc_lost > bbr->r_ctl.rc_lost_at_startup) && 11255 (bbr->r_ctl.rc_pkt_epoch_loss_rate > bbr_startup_loss_thresh)) && 11256 ((bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_bbr_last_startup_epoch) >= BBR_STARTUP_EPOCHS)) { 11257 /* 11258 * If we had no gain, we had loss and that loss was above 11259 * our threshould, the rwnd is not constrained, and we have 11260 * had at least 3 packet epochs exit. Note that this is 11261 * switched off by sysctl. Google does not do this by the 11262 * way. 11263 */ 11264 if ((ctf_flight_size(bbr->rc_tp, 11265 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)) + 11266 (2 * max(bbr->r_ctl.rc_pace_max_segs, bbr->rc_tp->t_maxseg))) <= bbr->rc_tp->snd_wnd) { 11267 do_exit = 1; 11268 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch, 11269 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 4); 11270 } else { 11271 /* Just record an updated loss value */ 11272 bbr->r_ctl.rc_lost_at_startup = bbr->r_ctl.rc_lost; 11273 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch, 11274 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 5); 11275 } 11276 } else 11277 bbr->r_ctl.rc_lost_at_startup = bbr->r_ctl.rc_lost; 11278 if (((bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_bbr_last_startup_epoch) >= BBR_STARTUP_EPOCHS) || 11279 do_exit) { 11280 /* Return 1 to exit the startup state. */ 11281 return (1); 11282 } 11283 /* Stay in startup */ 11284 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch, 11285 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 8); 11286 return (0); 11287 } 11288 11289 static void 11290 bbr_state_change(struct tcp_bbr *bbr, uint32_t cts, int32_t epoch, int32_t pkt_epoch, uint32_t losses) 11291 { 11292 /* 11293 * A tick occured in the rtt epoch do we need to do anything? 11294 */ 11295 #ifdef BBR_INVARIANTS 11296 if ((bbr->rc_bbr_state != BBR_STATE_STARTUP) && 11297 (bbr->rc_bbr_state != BBR_STATE_DRAIN) && 11298 (bbr->rc_bbr_state != BBR_STATE_PROBE_RTT) && 11299 (bbr->rc_bbr_state != BBR_STATE_IDLE_EXIT) && 11300 (bbr->rc_bbr_state != BBR_STATE_PROBE_BW)) { 11301 /* Debug code? */ 11302 panic("Unknown BBR state %d?\n", bbr->rc_bbr_state); 11303 } 11304 #endif 11305 if (bbr->rc_bbr_state == BBR_STATE_STARTUP) { 11306 /* Do we exit the startup state? */ 11307 if (bbr_state_startup(bbr, cts, epoch, pkt_epoch)) { 11308 uint32_t time_in; 11309 11310 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch, 11311 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 6); 11312 bbr->rc_filled_pipe = 1; 11313 bbr->r_ctl.bbr_lost_at_state = bbr->r_ctl.rc_lost; 11314 if (SEQ_GT(cts, bbr->r_ctl.rc_bbr_state_time)) { 11315 11316 time_in = cts - bbr->r_ctl.rc_bbr_state_time; 11317 counter_u64_add(bbr_state_time[bbr->rc_bbr_state], time_in); 11318 } else 11319 time_in = 0; 11320 if (bbr->rc_no_pacing) 11321 bbr->rc_no_pacing = 0; 11322 bbr->r_ctl.rc_bbr_state_time = cts; 11323 bbr->r_ctl.rc_bbr_hptsi_gain = bbr->r_ctl.rc_drain_pg; 11324 bbr->rc_bbr_state = BBR_STATE_DRAIN; 11325 bbr_set_state_target(bbr, __LINE__); 11326 if ((bbr->rc_use_google == 0) && 11327 bbr_slam_cwnd_in_main_drain) { 11328 /* Here we don't have to worry about probe-rtt */ 11329 bbr->r_ctl.rc_saved_cwnd = bbr->rc_tp->snd_cwnd; 11330 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_target_at_state; 11331 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 11332 } 11333 bbr->r_ctl.rc_bbr_cwnd_gain = bbr_high_gain; 11334 bbr_log_type_statechange(bbr, cts, __LINE__); 11335 if (ctf_flight_size(bbr->rc_tp, 11336 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)) <= 11337 bbr->r_ctl.rc_target_at_state) { 11338 /* 11339 * Switch to probe_bw if we are already 11340 * there 11341 */ 11342 bbr->rc_bbr_substate = bbr_pick_probebw_substate(bbr, cts); 11343 bbr_substate_change(bbr, cts, __LINE__, 0); 11344 bbr->rc_bbr_state = BBR_STATE_PROBE_BW; 11345 bbr_log_type_statechange(bbr, cts, __LINE__); 11346 } 11347 } 11348 } else if (bbr->rc_bbr_state == BBR_STATE_IDLE_EXIT) { 11349 uint32_t inflight; 11350 struct tcpcb *tp; 11351 11352 tp = bbr->rc_tp; 11353 inflight = ctf_flight_size(tp, 11354 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 11355 if (inflight >= bbr->r_ctl.rc_target_at_state) { 11356 /* We have reached a flight of the cwnd target */ 11357 bbr->rc_bbr_state = BBR_STATE_PROBE_BW; 11358 bbr->r_ctl.rc_bbr_hptsi_gain = BBR_UNIT; 11359 bbr->r_ctl.rc_bbr_cwnd_gain = BBR_UNIT; 11360 bbr_set_state_target(bbr, __LINE__); 11361 /* 11362 * Rig it so we don't do anything crazy and 11363 * start fresh with a new randomization. 11364 */ 11365 bbr->r_ctl.bbr_smallest_srtt_this_state = 0xffffffff; 11366 bbr->rc_bbr_substate = BBR_SUB_LEVEL6; 11367 bbr_substate_change(bbr, cts, __LINE__, 1); 11368 } 11369 } else if (bbr->rc_bbr_state == BBR_STATE_DRAIN) { 11370 /* Has in-flight reached the bdp (or less)? */ 11371 uint32_t inflight; 11372 struct tcpcb *tp; 11373 11374 tp = bbr->rc_tp; 11375 inflight = ctf_flight_size(tp, 11376 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 11377 if ((bbr->rc_use_google == 0) && 11378 bbr_slam_cwnd_in_main_drain && 11379 (bbr->rc_tp->snd_cwnd > bbr->r_ctl.rc_target_at_state)) { 11380 /* 11381 * Here we don't have to worry about probe-rtt 11382 * re-slam it, but keep it slammed down. 11383 */ 11384 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_target_at_state; 11385 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 11386 } 11387 if (inflight <= bbr->r_ctl.rc_target_at_state) { 11388 /* We have drained */ 11389 bbr->rc_bbr_state = BBR_STATE_PROBE_BW; 11390 bbr->r_ctl.bbr_lost_at_state = bbr->r_ctl.rc_lost; 11391 if (SEQ_GT(cts, bbr->r_ctl.rc_bbr_state_time)) { 11392 uint32_t time_in; 11393 11394 time_in = cts - bbr->r_ctl.rc_bbr_state_time; 11395 counter_u64_add(bbr_state_time[bbr->rc_bbr_state], time_in); 11396 } 11397 if ((bbr->rc_use_google == 0) && 11398 bbr_slam_cwnd_in_main_drain && 11399 (tp->snd_cwnd < bbr->r_ctl.rc_saved_cwnd)) { 11400 /* Restore the cwnd */ 11401 tp->snd_cwnd = bbr->r_ctl.rc_saved_cwnd; 11402 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 11403 } 11404 /* Setup probe-rtt has being done now RRS-HERE */ 11405 bbr->r_ctl.rc_rtt_shrinks = cts; 11406 bbr->r_ctl.last_in_probertt = cts; 11407 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_LEAVE_DRAIN, 0); 11408 /* Randomly pick a sub-state */ 11409 bbr->rc_bbr_substate = bbr_pick_probebw_substate(bbr, cts); 11410 bbr_substate_change(bbr, cts, __LINE__, 0); 11411 bbr_log_type_statechange(bbr, cts, __LINE__); 11412 } 11413 } else if (bbr->rc_bbr_state == BBR_STATE_PROBE_RTT) { 11414 uint32_t flight; 11415 11416 flight = ctf_flight_size(bbr->rc_tp, 11417 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 11418 bbr->r_ctl.r_app_limited_until = (flight + bbr->r_ctl.rc_delivered); 11419 if (((bbr->r_ctl.bbr_rttprobe_gain_val == 0) || bbr->rc_use_google) && 11420 (bbr->rc_tp->snd_cwnd > bbr->r_ctl.rc_target_at_state)) { 11421 /* 11422 * We must keep cwnd at the desired MSS. 11423 */ 11424 bbr->rc_tp->snd_cwnd = bbr_rtt_probe_cwndtarg * (bbr->rc_tp->t_maxseg - bbr->rc_last_options); 11425 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 11426 } else if ((bbr_prtt_slam_cwnd) && 11427 (bbr->rc_tp->snd_cwnd > bbr->r_ctl.rc_target_at_state)) { 11428 /* Re-slam it */ 11429 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_target_at_state; 11430 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 11431 } 11432 if (bbr->r_ctl.rc_bbr_enters_probertt == 0) { 11433 /* Has outstanding reached our target? */ 11434 if (flight <= bbr->r_ctl.rc_target_at_state) { 11435 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_REACHTAR, 0); 11436 bbr->r_ctl.rc_bbr_enters_probertt = cts; 11437 /* If time is exactly 0, be 1usec off */ 11438 if (bbr->r_ctl.rc_bbr_enters_probertt == 0) 11439 bbr->r_ctl.rc_bbr_enters_probertt = 1; 11440 if (bbr->rc_use_google == 0) { 11441 /* 11442 * Restore any lowering that as occured to 11443 * reach here 11444 */ 11445 if (bbr->r_ctl.bbr_rttprobe_gain_val) 11446 bbr->r_ctl.rc_bbr_hptsi_gain = bbr->r_ctl.bbr_rttprobe_gain_val; 11447 else 11448 bbr->r_ctl.rc_bbr_hptsi_gain = BBR_UNIT; 11449 } 11450 } 11451 if ((bbr->r_ctl.rc_bbr_enters_probertt == 0) && 11452 (bbr->rc_use_google == 0) && 11453 bbr->r_ctl.bbr_rttprobe_gain_val && 11454 (((cts - bbr->r_ctl.rc_probertt_srttchktim) > bbr_get_rtt(bbr, bbr_drain_rtt)) || 11455 (flight >= bbr->r_ctl.flightsize_at_drain))) { 11456 /* 11457 * We have doddled with our current hptsi 11458 * gain an srtt and have still not made it 11459 * to target, or we have increased our flight. 11460 * Lets reduce the gain by xx% 11461 * flooring the reduce at DRAIN (based on 11462 * mul/div) 11463 */ 11464 int red; 11465 11466 bbr->r_ctl.flightsize_at_drain = flight; 11467 bbr->r_ctl.rc_probertt_srttchktim = cts; 11468 red = max((bbr->r_ctl.bbr_rttprobe_gain_val / 10), 1); 11469 if ((bbr->r_ctl.rc_bbr_hptsi_gain - red) > max(bbr_drain_floor, 1)) { 11470 /* Reduce our gain again */ 11471 bbr->r_ctl.rc_bbr_hptsi_gain -= red; 11472 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_SHRINK_PG, 0); 11473 } else if (bbr->r_ctl.rc_bbr_hptsi_gain > max(bbr_drain_floor, 1)) { 11474 /* one more chance before we give up */ 11475 bbr->r_ctl.rc_bbr_hptsi_gain = max(bbr_drain_floor, 1); 11476 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_SHRINK_PG_FINAL, 0); 11477 } else { 11478 /* At the very bottom */ 11479 bbr->r_ctl.rc_bbr_hptsi_gain = max((bbr_drain_floor-1), 1); 11480 } 11481 } 11482 } 11483 if (bbr->r_ctl.rc_bbr_enters_probertt && 11484 (TSTMP_GT(cts, bbr->r_ctl.rc_bbr_enters_probertt)) && 11485 ((cts - bbr->r_ctl.rc_bbr_enters_probertt) >= bbr_rtt_probe_time)) { 11486 /* Time to exit probe RTT normally */ 11487 bbr_exit_probe_rtt(bbr->rc_tp, bbr, cts); 11488 } 11489 } else if (bbr->rc_bbr_state == BBR_STATE_PROBE_BW) { 11490 if ((bbr->rc_tp->snd_una == bbr->rc_tp->snd_max) && 11491 (bbr_calc_time(cts, bbr->r_ctl.rc_went_idle_time) >= bbr_rtt_probe_time)) { 11492 /* 11493 * This qualifies as a RTT_PROBE session since we 11494 * drop the data outstanding to nothing and waited 11495 * more than bbr_rtt_probe_time. 11496 */ 11497 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_WASIDLE, 0); 11498 bbr_set_reduced_rtt(bbr, cts, __LINE__); 11499 } 11500 if (bbr_should_enter_probe_rtt(bbr, cts)) { 11501 bbr_enter_probe_rtt(bbr, cts, __LINE__); 11502 } else { 11503 bbr_set_probebw_gains(bbr, cts, losses); 11504 } 11505 } 11506 } 11507 11508 static void 11509 bbr_check_bbr_for_state(struct tcp_bbr *bbr, uint32_t cts, int32_t line, uint32_t losses) 11510 { 11511 int32_t epoch = 0; 11512 11513 if ((cts - bbr->r_ctl.rc_rcv_epoch_start) >= bbr_get_rtt(bbr, BBR_RTT_PROP)) { 11514 bbr_set_epoch(bbr, cts, line); 11515 /* At each epoch doe lt bw sampling */ 11516 epoch = 1; 11517 } 11518 bbr_state_change(bbr, cts, epoch, bbr->rc_is_pkt_epoch_now, losses); 11519 } 11520 11521 static int 11522 bbr_do_segment_nounlock(struct mbuf *m, struct tcphdr *th, struct socket *so, 11523 struct tcpcb *tp, int32_t drop_hdrlen, int32_t tlen, uint8_t iptos, 11524 int32_t nxt_pkt, struct timeval *tv) 11525 { 11526 int32_t thflags, retval; 11527 uint32_t cts, lcts; 11528 uint32_t tiwin; 11529 struct tcpopt to; 11530 struct tcp_bbr *bbr; 11531 struct bbr_sendmap *rsm; 11532 struct timeval ltv; 11533 int32_t did_out = 0; 11534 int32_t in_recovery; 11535 uint16_t nsegs; 11536 int32_t prev_state; 11537 uint32_t lost; 11538 11539 nsegs = max(1, m->m_pkthdr.lro_nsegs); 11540 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 11541 /* add in our stats */ 11542 kern_prefetch(bbr, &prev_state); 11543 prev_state = 0; 11544 thflags = th->th_flags; 11545 /* 11546 * If this is either a state-changing packet or current state isn't 11547 * established, we require a write lock on tcbinfo. Otherwise, we 11548 * allow the tcbinfo to be in either alocked or unlocked, as the 11549 * caller may have unnecessarily acquired a write lock due to a 11550 * race. 11551 */ 11552 INP_WLOCK_ASSERT(tp->t_inpcb); 11553 KASSERT(tp->t_state > TCPS_LISTEN, ("%s: TCPS_LISTEN", 11554 __func__)); 11555 KASSERT(tp->t_state != TCPS_TIME_WAIT, ("%s: TCPS_TIME_WAIT", 11556 __func__)); 11557 11558 tp->t_rcvtime = ticks; 11559 /* 11560 * Unscale the window into a 32-bit value. For the SYN_SENT state 11561 * the scale is zero. 11562 */ 11563 tiwin = th->th_win << tp->snd_scale; 11564 #ifdef NETFLIX_STATS 11565 stats_voi_update_abs_ulong(tp->t_stats, VOI_TCP_FRWIN, tiwin); 11566 #endif 11567 /* 11568 * Parse options on any incoming segment. 11569 */ 11570 tcp_dooptions(&to, (u_char *)(th + 1), 11571 (th->th_off << 2) - sizeof(struct tcphdr), 11572 (thflags & TH_SYN) ? TO_SYN : 0); 11573 11574 if (m->m_flags & M_TSTMP) { 11575 /* Prefer the hardware timestamp if present */ 11576 struct timespec ts; 11577 11578 mbuf_tstmp2timespec(m, &ts); 11579 bbr->rc_tv.tv_sec = ts.tv_sec; 11580 bbr->rc_tv.tv_usec = ts.tv_nsec / 1000; 11581 bbr->r_ctl.rc_rcvtime = cts = tcp_tv_to_usectick(&bbr->rc_tv); 11582 } else if (m->m_flags & M_TSTMP_LRO) { 11583 /* Next the arrival timestamp */ 11584 struct timespec ts; 11585 11586 mbuf_tstmp2timespec(m, &ts); 11587 bbr->rc_tv.tv_sec = ts.tv_sec; 11588 bbr->rc_tv.tv_usec = ts.tv_nsec / 1000; 11589 bbr->r_ctl.rc_rcvtime = cts = tcp_tv_to_usectick(&bbr->rc_tv); 11590 } else { 11591 /* 11592 * Ok just get the current time. 11593 */ 11594 bbr->r_ctl.rc_rcvtime = lcts = cts = tcp_get_usecs(&bbr->rc_tv); 11595 } 11596 /* 11597 * If echoed timestamp is later than the current time, fall back to 11598 * non RFC1323 RTT calculation. Normalize timestamp if syncookies 11599 * were used when this connection was established. 11600 */ 11601 if ((to.to_flags & TOF_TS) && (to.to_tsecr != 0)) { 11602 to.to_tsecr -= tp->ts_offset; 11603 if (TSTMP_GT(to.to_tsecr, tcp_tv_to_mssectick(&bbr->rc_tv))) 11604 to.to_tsecr = 0; 11605 } 11606 /* 11607 * If its the first time in we need to take care of options and 11608 * verify we can do SACK for rack! 11609 */ 11610 if (bbr->r_state == 0) { 11611 /* 11612 * Process options only when we get SYN/ACK back. The SYN 11613 * case for incoming connections is handled in tcp_syncache. 11614 * According to RFC1323 the window field in a SYN (i.e., a 11615 * <SYN> or <SYN,ACK>) segment itself is never scaled. XXX 11616 * this is traditional behavior, may need to be cleaned up. 11617 */ 11618 if (bbr->rc_inp == NULL) { 11619 bbr->rc_inp = tp->t_inpcb; 11620 } 11621 /* 11622 * We need to init rc_inp here since its not init'd when 11623 * bbr_init is called 11624 */ 11625 if (tp->t_state == TCPS_SYN_SENT && (thflags & TH_SYN)) { 11626 if ((to.to_flags & TOF_SCALE) && 11627 (tp->t_flags & TF_REQ_SCALE)) { 11628 tp->t_flags |= TF_RCVD_SCALE; 11629 tp->snd_scale = to.to_wscale; 11630 } 11631 /* 11632 * Initial send window. It will be updated with the 11633 * next incoming segment to the scaled value. 11634 */ 11635 tp->snd_wnd = th->th_win; 11636 if (to.to_flags & TOF_TS) { 11637 tp->t_flags |= TF_RCVD_TSTMP; 11638 tp->ts_recent = to.to_tsval; 11639 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv); 11640 } 11641 if (to.to_flags & TOF_MSS) 11642 tcp_mss(tp, to.to_mss); 11643 if ((tp->t_flags & TF_SACK_PERMIT) && 11644 (to.to_flags & TOF_SACKPERM) == 0) 11645 tp->t_flags &= ~TF_SACK_PERMIT; 11646 if (IS_FASTOPEN(tp->t_flags)) { 11647 if (to.to_flags & TOF_FASTOPEN) { 11648 uint16_t mss; 11649 11650 if (to.to_flags & TOF_MSS) 11651 mss = to.to_mss; 11652 else 11653 if ((tp->t_inpcb->inp_vflag & INP_IPV6) != 0) 11654 mss = TCP6_MSS; 11655 else 11656 mss = TCP_MSS; 11657 tcp_fastopen_update_cache(tp, mss, 11658 to.to_tfo_len, to.to_tfo_cookie); 11659 } else 11660 tcp_fastopen_disable_path(tp); 11661 } 11662 } 11663 /* 11664 * At this point we are at the initial call. Here we decide 11665 * if we are doing RACK or not. We do this by seeing if 11666 * TF_SACK_PERMIT is set, if not rack is *not* possible and 11667 * we switch to the default code. 11668 */ 11669 if ((tp->t_flags & TF_SACK_PERMIT) == 0) { 11670 /* Bail */ 11671 tcp_switch_back_to_default(tp); 11672 (*tp->t_fb->tfb_tcp_do_segment) (m, th, so, tp, drop_hdrlen, 11673 tlen, iptos); 11674 return (1); 11675 } 11676 /* Set the flag */ 11677 bbr->r_is_v6 = (tp->t_inpcb->inp_vflag & INP_IPV6) != 0; 11678 tcp_set_hpts(tp->t_inpcb); 11679 sack_filter_clear(&bbr->r_ctl.bbr_sf, th->th_ack); 11680 } 11681 if (thflags & TH_ACK) { 11682 /* Track ack types */ 11683 if (to.to_flags & TOF_SACK) 11684 BBR_STAT_INC(bbr_acks_with_sacks); 11685 else 11686 BBR_STAT_INC(bbr_plain_acks); 11687 } 11688 /* 11689 * This is the one exception case where we set the rack state 11690 * always. All other times (timers etc) we must have a rack-state 11691 * set (so we assure we have done the checks above for SACK). 11692 */ 11693 if (bbr->r_state != tp->t_state) 11694 bbr_set_state(tp, bbr, tiwin); 11695 11696 if (SEQ_GT(th->th_ack, tp->snd_una) && (rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map)) != NULL) 11697 kern_prefetch(rsm, &prev_state); 11698 prev_state = bbr->r_state; 11699 bbr->rc_ack_was_delayed = 0; 11700 lost = bbr->r_ctl.rc_lost; 11701 bbr->rc_is_pkt_epoch_now = 0; 11702 if (m->m_flags & (M_TSTMP|M_TSTMP_LRO)) { 11703 /* Get the real time into lcts and figure the real delay */ 11704 lcts = tcp_get_usecs(<v); 11705 if (TSTMP_GT(lcts, cts)) { 11706 bbr->r_ctl.rc_ack_hdwr_delay = lcts - cts; 11707 bbr->rc_ack_was_delayed = 1; 11708 if (TSTMP_GT(bbr->r_ctl.rc_ack_hdwr_delay, 11709 bbr->r_ctl.highest_hdwr_delay)) 11710 bbr->r_ctl.highest_hdwr_delay = bbr->r_ctl.rc_ack_hdwr_delay; 11711 } else { 11712 bbr->r_ctl.rc_ack_hdwr_delay = 0; 11713 bbr->rc_ack_was_delayed = 0; 11714 } 11715 } else { 11716 bbr->r_ctl.rc_ack_hdwr_delay = 0; 11717 bbr->rc_ack_was_delayed = 0; 11718 } 11719 bbr_log_ack_event(bbr, th, &to, tlen, nsegs, cts, nxt_pkt, m); 11720 if ((thflags & TH_SYN) && (thflags & TH_FIN) && V_drop_synfin) { 11721 retval = 0; 11722 m_freem(m); 11723 goto done_with_input; 11724 } 11725 /* 11726 * If a segment with the ACK-bit set arrives in the SYN-SENT state 11727 * check SEQ.ACK first as described on page 66 of RFC 793, section 3.9. 11728 */ 11729 if ((tp->t_state == TCPS_SYN_SENT) && (thflags & TH_ACK) && 11730 (SEQ_LEQ(th->th_ack, tp->iss) || SEQ_GT(th->th_ack, tp->snd_max))) { 11731 ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen); 11732 return (1); 11733 } 11734 in_recovery = IN_RECOVERY(tp->t_flags); 11735 if (tiwin > bbr->r_ctl.rc_high_rwnd) 11736 bbr->r_ctl.rc_high_rwnd = tiwin; 11737 #ifdef BBR_INVARIANTS 11738 if ((tp->t_inpcb->inp_flags & INP_DROPPED) || 11739 (tp->t_inpcb->inp_flags2 & INP_FREED)) { 11740 panic("tp:%p bbr:%p given a dropped inp:%p", 11741 tp, bbr, tp->t_inpcb); 11742 } 11743 #endif 11744 bbr->r_ctl.rc_flight_at_input = ctf_flight_size(tp, 11745 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 11746 bbr->rtt_valid = 0; 11747 if (to.to_flags & TOF_TS) { 11748 bbr->rc_ts_valid = 1; 11749 bbr->r_ctl.last_inbound_ts = to.to_tsval; 11750 } else { 11751 bbr->rc_ts_valid = 0; 11752 bbr->r_ctl.last_inbound_ts = 0; 11753 } 11754 retval = (*bbr->r_substate) (m, th, so, 11755 tp, &to, drop_hdrlen, 11756 tlen, tiwin, thflags, nxt_pkt); 11757 #ifdef BBR_INVARIANTS 11758 if ((retval == 0) && 11759 (tp->t_inpcb == NULL)) { 11760 panic("retval:%d tp:%p t_inpcb:NULL state:%d", 11761 retval, tp, prev_state); 11762 } 11763 #endif 11764 if (nxt_pkt == 0) 11765 BBR_STAT_INC(bbr_rlock_left_ret0); 11766 else 11767 BBR_STAT_INC(bbr_rlock_left_ret1); 11768 if (retval == 0) { 11769 /* 11770 * If retval is 1 the tcb is unlocked and most likely the tp 11771 * is gone. 11772 */ 11773 INP_WLOCK_ASSERT(tp->t_inpcb); 11774 tcp_bbr_xmit_timer_commit(bbr, tp, cts); 11775 if (bbr->rc_is_pkt_epoch_now) 11776 bbr_set_pktepoch(bbr, cts, __LINE__); 11777 bbr_check_bbr_for_state(bbr, cts, __LINE__, (bbr->r_ctl.rc_lost - lost)); 11778 if (nxt_pkt == 0) { 11779 if (bbr->r_wanted_output != 0) { 11780 bbr->rc_output_starts_timer = 0; 11781 did_out = 1; 11782 (void)tp->t_fb->tfb_tcp_output(tp); 11783 } else 11784 bbr_start_hpts_timer(bbr, tp, cts, 6, 0, 0); 11785 } 11786 if ((nxt_pkt == 0) && 11787 ((bbr->r_ctl.rc_hpts_flags & PACE_TMR_MASK) == 0) && 11788 (SEQ_GT(tp->snd_max, tp->snd_una) || 11789 (tp->t_flags & TF_DELACK) || 11790 ((tcp_always_keepalive || bbr->rc_inp->inp_socket->so_options & SO_KEEPALIVE) && 11791 (tp->t_state <= TCPS_CLOSING)))) { 11792 /* 11793 * We could not send (probably in the hpts but 11794 * stopped the timer)? 11795 */ 11796 if ((tp->snd_max == tp->snd_una) && 11797 ((tp->t_flags & TF_DELACK) == 0) && 11798 (bbr->rc_inp->inp_in_hpts) && 11799 (bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT)) { 11800 /* 11801 * keep alive not needed if we are hptsi 11802 * output yet 11803 */ 11804 ; 11805 } else { 11806 if (bbr->rc_inp->inp_in_hpts) { 11807 tcp_hpts_remove(bbr->rc_inp, HPTS_REMOVE_OUTPUT); 11808 if ((bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) && 11809 (TSTMP_GT(lcts, bbr->rc_pacer_started))) { 11810 uint32_t del; 11811 11812 del = lcts - bbr->rc_pacer_started; 11813 if (bbr->r_ctl.rc_last_delay_val > del) { 11814 BBR_STAT_INC(bbr_force_timer_start); 11815 bbr->r_ctl.rc_last_delay_val -= del; 11816 bbr->rc_pacer_started = lcts; 11817 } else { 11818 /* We are late */ 11819 bbr->r_ctl.rc_last_delay_val = 0; 11820 BBR_STAT_INC(bbr_force_output); 11821 (void)tp->t_fb->tfb_tcp_output(tp); 11822 } 11823 } 11824 } 11825 bbr_start_hpts_timer(bbr, tp, cts, 8, bbr->r_ctl.rc_last_delay_val, 11826 0); 11827 } 11828 } else if ((bbr->rc_output_starts_timer == 0) && (nxt_pkt == 0)) { 11829 /* Do we have the correct timer running? */ 11830 bbr_timer_audit(tp, bbr, lcts, &so->so_snd); 11831 } 11832 /* Do we have a new state */ 11833 if (bbr->r_state != tp->t_state) 11834 bbr_set_state(tp, bbr, tiwin); 11835 done_with_input: 11836 bbr_log_doseg_done(bbr, cts, nxt_pkt, did_out); 11837 if (did_out) 11838 bbr->r_wanted_output = 0; 11839 #ifdef BBR_INVARIANTS 11840 if (tp->t_inpcb == NULL) { 11841 panic("OP:%d retval:%d tp:%p t_inpcb:NULL state:%d", 11842 did_out, 11843 retval, tp, prev_state); 11844 } 11845 #endif 11846 } 11847 return (retval); 11848 } 11849 11850 static void 11851 bbr_log_type_hrdwtso(struct tcpcb *tp, struct tcp_bbr *bbr, int len, int mod, int what_we_can_send) 11852 { 11853 if (tp->t_logstate != TCP_LOG_STATE_OFF) { 11854 union tcp_log_stackspecific log; 11855 struct timeval tv; 11856 uint32_t cts; 11857 11858 cts = tcp_get_usecs(&tv); 11859 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 11860 log.u_bbr.flex1 = bbr->r_ctl.rc_pace_min_segs; 11861 log.u_bbr.flex2 = what_we_can_send; 11862 log.u_bbr.flex3 = bbr->r_ctl.rc_pace_max_segs; 11863 log.u_bbr.flex4 = len; 11864 log.u_bbr.flex5 = 0; 11865 log.u_bbr.flex7 = mod; 11866 log.u_bbr.flex8 = 1; 11867 TCP_LOG_EVENTP(tp, NULL, 11868 &tp->t_inpcb->inp_socket->so_rcv, 11869 &tp->t_inpcb->inp_socket->so_snd, 11870 TCP_HDWR_TLS, 0, 11871 0, &log, false, &tv); 11872 } 11873 } 11874 11875 static void 11876 bbr_do_segment(struct mbuf *m, struct tcphdr *th, struct socket *so, 11877 struct tcpcb *tp, int32_t drop_hdrlen, int32_t tlen, uint8_t iptos) 11878 { 11879 struct timeval tv; 11880 int retval; 11881 11882 /* First lets see if we have old packets */ 11883 if (tp->t_in_pkt) { 11884 if (ctf_do_queued_segments(so, tp, 1)) { 11885 m_freem(m); 11886 return; 11887 } 11888 } 11889 if (m->m_flags & M_TSTMP_LRO) { 11890 tv.tv_sec = m->m_pkthdr.rcv_tstmp /1000000000; 11891 tv.tv_usec = (m->m_pkthdr.rcv_tstmp % 1000000000)/1000; 11892 } else { 11893 /* Should not be should we kassert instead? */ 11894 tcp_get_usecs(&tv); 11895 } 11896 retval = bbr_do_segment_nounlock(m, th, so, tp, 11897 drop_hdrlen, tlen, iptos, 0, &tv); 11898 if (retval == 0) 11899 INP_WUNLOCK(tp->t_inpcb); 11900 } 11901 11902 /* 11903 * Return how much data can be sent without violating the 11904 * cwnd or rwnd. 11905 */ 11906 11907 static inline uint32_t 11908 bbr_what_can_we_send(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t sendwin, 11909 uint32_t avail, int32_t sb_offset, uint32_t cts) 11910 { 11911 uint32_t len; 11912 11913 if (ctf_outstanding(tp) >= tp->snd_wnd) { 11914 /* We never want to go over our peers rcv-window */ 11915 len = 0; 11916 } else { 11917 uint32_t flight; 11918 11919 flight = ctf_flight_size(tp, (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 11920 if (flight >= sendwin) { 11921 /* 11922 * We have in flight what we are allowed by cwnd (if 11923 * it was rwnd blocking it would have hit above out 11924 * >= tp->snd_wnd). 11925 */ 11926 return (0); 11927 } 11928 len = sendwin - flight; 11929 if ((len + ctf_outstanding(tp)) > tp->snd_wnd) { 11930 /* We would send too much (beyond the rwnd) */ 11931 len = tp->snd_wnd - ctf_outstanding(tp); 11932 } 11933 if ((len + sb_offset) > avail) { 11934 /* 11935 * We don't have that much in the SB, how much is 11936 * there? 11937 */ 11938 len = avail - sb_offset; 11939 } 11940 } 11941 return (len); 11942 } 11943 11944 static inline void 11945 bbr_do_error_accounting(struct tcpcb *tp, struct tcp_bbr *bbr, struct bbr_sendmap *rsm, int32_t len, int32_t error) 11946 { 11947 #ifdef NETFLIX_STATS 11948 TCPSTAT_INC(tcps_sndpack_error); 11949 TCPSTAT_ADD(tcps_sndbyte_error, len); 11950 #endif 11951 } 11952 11953 static inline void 11954 bbr_do_send_accounting(struct tcpcb *tp, struct tcp_bbr *bbr, struct bbr_sendmap *rsm, int32_t len, int32_t error) 11955 { 11956 if (error) { 11957 bbr_do_error_accounting(tp, bbr, rsm, len, error); 11958 return; 11959 } 11960 if ((tp->t_flags & TF_FORCEDATA) && len == 1) { 11961 /* Window probe */ 11962 TCPSTAT_INC(tcps_sndprobe); 11963 #ifdef NETFLIX_STATS 11964 stats_voi_update_abs_u32(tp->t_stats, 11965 VOI_TCP_RETXPB, len); 11966 #endif 11967 } else if (rsm) { 11968 if (rsm->r_flags & BBR_TLP) { 11969 /* 11970 * TLP should not count in retran count, but in its 11971 * own bin 11972 */ 11973 #ifdef NETFLIX_STATS 11974 tp->t_sndtlppack++; 11975 tp->t_sndtlpbyte += len; 11976 TCPSTAT_INC(tcps_tlpresends); 11977 TCPSTAT_ADD(tcps_tlpresend_bytes, len); 11978 #endif 11979 } else { 11980 /* Retransmit */ 11981 tp->t_sndrexmitpack++; 11982 TCPSTAT_INC(tcps_sndrexmitpack); 11983 TCPSTAT_ADD(tcps_sndrexmitbyte, len); 11984 #ifdef NETFLIX_STATS 11985 stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_RETXPB, 11986 len); 11987 #endif 11988 } 11989 /* 11990 * Logs in 0 - 8, 8 is all non probe_bw states 0-7 is 11991 * sub-state 11992 */ 11993 counter_u64_add(bbr_state_lost[rsm->r_bbr_state], len); 11994 if (bbr->rc_bbr_state != BBR_STATE_PROBE_BW) { 11995 /* Non probe_bw log in 1, 2, or 4. */ 11996 counter_u64_add(bbr_state_resend[bbr->rc_bbr_state], len); 11997 } else { 11998 /* 11999 * Log our probe state 3, and log also 5-13 to show 12000 * us the recovery sub-state for the send. This 12001 * means that 3 == (5+6+7+8+9+10+11+12+13) 12002 */ 12003 counter_u64_add(bbr_state_resend[BBR_STATE_PROBE_BW], len); 12004 counter_u64_add(bbr_state_resend[(bbr_state_val(bbr) + 5)], len); 12005 } 12006 /* Place in both 16's the totals of retransmitted */ 12007 counter_u64_add(bbr_state_lost[16], len); 12008 counter_u64_add(bbr_state_resend[16], len); 12009 /* Place in 17's the total sent */ 12010 counter_u64_add(bbr_state_resend[17], len); 12011 counter_u64_add(bbr_state_lost[17], len); 12012 12013 } else { 12014 /* New sends */ 12015 TCPSTAT_INC(tcps_sndpack); 12016 TCPSTAT_ADD(tcps_sndbyte, len); 12017 /* Place in 17's the total sent */ 12018 counter_u64_add(bbr_state_resend[17], len); 12019 counter_u64_add(bbr_state_lost[17], len); 12020 #ifdef NETFLIX_STATS 12021 stats_voi_update_abs_u64(tp->t_stats, VOI_TCP_TXPB, 12022 len); 12023 #endif 12024 } 12025 } 12026 12027 static void 12028 bbr_cwnd_limiting(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t in_level) 12029 { 12030 if (bbr->rc_filled_pipe && bbr_target_cwnd_mult_limit && (bbr->rc_use_google == 0)) { 12031 /* 12032 * Limit the cwnd to not be above N x the target plus whats 12033 * is outstanding. The target is based on the current b/w 12034 * estimate. 12035 */ 12036 uint32_t target; 12037 12038 target = bbr_get_target_cwnd(bbr, bbr_get_bw(bbr), BBR_UNIT); 12039 target += ctf_outstanding(tp); 12040 target *= bbr_target_cwnd_mult_limit; 12041 if (tp->snd_cwnd > target) 12042 tp->snd_cwnd = target; 12043 bbr_log_type_cwndupd(bbr, 0, 0, 0, 10, 0, 0, __LINE__); 12044 } 12045 } 12046 12047 static int 12048 bbr_window_update_needed(struct tcpcb *tp, struct socket *so, uint32_t recwin, int32_t maxseg) 12049 { 12050 /* 12051 * "adv" is the amount we could increase the window, taking into 12052 * account that we are limited by TCP_MAXWIN << tp->rcv_scale. 12053 */ 12054 uint32_t adv; 12055 int32_t oldwin; 12056 12057 adv = min(recwin, TCP_MAXWIN << tp->rcv_scale); 12058 if (SEQ_GT(tp->rcv_adv, tp->rcv_nxt)) { 12059 oldwin = (tp->rcv_adv - tp->rcv_nxt); 12060 adv -= oldwin; 12061 } else 12062 oldwin = 0; 12063 12064 /* 12065 * If the new window size ends up being the same as the old size 12066 * when it is scaled, then don't force a window update. 12067 */ 12068 if (oldwin >> tp->rcv_scale == (adv + oldwin) >> tp->rcv_scale) 12069 return (0); 12070 12071 if (adv >= (2 * maxseg) && 12072 (adv >= (so->so_rcv.sb_hiwat / 4) || 12073 recwin <= (so->so_rcv.sb_hiwat / 8) || 12074 so->so_rcv.sb_hiwat <= 8 * maxseg)) { 12075 return (1); 12076 } 12077 if (2 * adv >= (int32_t) so->so_rcv.sb_hiwat) 12078 return (1); 12079 return (0); 12080 } 12081 12082 /* 12083 * Return 0 on success and a errno on failure to send. 12084 * Note that a 0 return may not mean we sent anything 12085 * if the TCB was on the hpts. A non-zero return 12086 * does indicate the error we got from ip[6]_output. 12087 */ 12088 static int 12089 bbr_output_wtime(struct tcpcb *tp, const struct timeval *tv) 12090 { 12091 struct socket *so; 12092 int32_t len; 12093 uint32_t cts; 12094 uint32_t recwin, sendwin; 12095 int32_t sb_offset; 12096 int32_t flags, abandon, error = 0; 12097 struct tcp_log_buffer *lgb = NULL; 12098 struct mbuf *m; 12099 struct mbuf *mb; 12100 uint32_t if_hw_tsomaxsegcount = 0; 12101 uint32_t if_hw_tsomaxsegsize = 0; 12102 uint32_t if_hw_tsomax = 0; 12103 struct ip *ip = NULL; 12104 #ifdef TCPDEBUG 12105 struct ipovly *ipov = NULL; 12106 #endif 12107 struct tcp_bbr *bbr; 12108 struct tcphdr *th; 12109 #ifdef NETFLIX_TCPOUDP 12110 struct udphdr *udp = NULL; 12111 #endif 12112 u_char opt[TCP_MAXOLEN]; 12113 unsigned ipoptlen, optlen, hdrlen; 12114 #ifdef NETFLIX_TCPOUDP 12115 unsigned ulen; 12116 #endif 12117 uint32_t bbr_seq; 12118 uint32_t delay_calc=0; 12119 uint8_t doing_tlp = 0; 12120 uint8_t local_options; 12121 #ifdef BBR_INVARIANTS 12122 uint8_t doing_retran_from = 0; 12123 uint8_t picked_up_retran = 0; 12124 #endif 12125 uint8_t wanted_cookie = 0; 12126 uint8_t more_to_rxt=0; 12127 int32_t prefetch_so_done = 0; 12128 int32_t prefetch_rsm = 0; 12129 uint32_t what_we_can = 0; 12130 uint32_t tot_len = 0; 12131 uint32_t rtr_cnt = 0; 12132 uint32_t maxseg, pace_max_segs, p_maxseg; 12133 int32_t csum_flags; 12134 int32_t hw_tls; 12135 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 12136 unsigned ipsec_optlen = 0; 12137 12138 #endif 12139 volatile int32_t sack_rxmit; 12140 struct bbr_sendmap *rsm = NULL; 12141 int32_t tso, mtu; 12142 int force_tso = 0; 12143 struct tcpopt to; 12144 int32_t slot = 0; 12145 struct inpcb *inp; 12146 struct sockbuf *sb; 12147 uint32_t hpts_calling; 12148 #ifdef INET6 12149 struct ip6_hdr *ip6 = NULL; 12150 int32_t isipv6; 12151 #endif 12152 uint8_t app_limited = BBR_JR_SENT_DATA; 12153 uint8_t filled_all = 0; 12154 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 12155 /* We take a cache hit here */ 12156 memcpy(&bbr->rc_tv, tv, sizeof(struct timeval)); 12157 cts = tcp_tv_to_usectick(&bbr->rc_tv); 12158 inp = bbr->rc_inp; 12159 so = inp->inp_socket; 12160 sb = &so->so_snd; 12161 #ifdef KERN_TLS 12162 if (sb->sb_flags & SB_TLS_IFNET) 12163 hw_tls = 1; 12164 else 12165 #endif 12166 hw_tls = 0; 12167 kern_prefetch(sb, &maxseg); 12168 maxseg = tp->t_maxseg - bbr->rc_last_options; 12169 if (bbr_minseg(bbr) < maxseg) { 12170 tcp_bbr_tso_size_check(bbr, cts); 12171 } 12172 /* Remove any flags that indicate we are pacing on the inp */ 12173 pace_max_segs = bbr->r_ctl.rc_pace_max_segs; 12174 p_maxseg = min(maxseg, pace_max_segs); 12175 INP_WLOCK_ASSERT(inp); 12176 #ifdef TCP_OFFLOAD 12177 if (tp->t_flags & TF_TOE) 12178 return (tcp_offload_output(tp)); 12179 #endif 12180 12181 #ifdef INET6 12182 if (bbr->r_state) { 12183 /* Use the cache line loaded if possible */ 12184 isipv6 = bbr->r_is_v6; 12185 } else { 12186 isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 12187 } 12188 #endif 12189 if (((bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) == 0) && 12190 inp->inp_in_hpts) { 12191 /* 12192 * We are on the hpts for some timer but not hptsi output. 12193 * Possibly remove from the hpts so we can send/recv etc. 12194 */ 12195 if ((tp->t_flags & TF_ACKNOW) == 0) { 12196 /* 12197 * No immediate demand right now to send an ack, but 12198 * the user may have read, making room for new data 12199 * (a window update). If so we may want to cancel 12200 * whatever timer is running (KEEP/DEL-ACK?) and 12201 * continue to send out a window update. Or we may 12202 * have gotten more data into the socket buffer to 12203 * send. 12204 */ 12205 recwin = min(max(sbspace(&so->so_rcv), 0), 12206 TCP_MAXWIN << tp->rcv_scale); 12207 if ((bbr_window_update_needed(tp, so, recwin, maxseg) == 0) && 12208 ((sbavail(sb) + ((tcp_outflags[tp->t_state] & TH_FIN) ? 1 : 0)) <= 12209 (tp->snd_max - tp->snd_una))) { 12210 /* 12211 * Nothing new to send and no window update 12212 * is needed to send. Lets just return and 12213 * let the timer-run off. 12214 */ 12215 return (0); 12216 } 12217 } 12218 tcp_hpts_remove(inp, HPTS_REMOVE_OUTPUT); 12219 bbr_timer_cancel(bbr, __LINE__, cts); 12220 } 12221 if (bbr->r_ctl.rc_last_delay_val) { 12222 /* Calculate a rough delay for early escape to sending */ 12223 if (SEQ_GT(cts, bbr->rc_pacer_started)) 12224 delay_calc = cts - bbr->rc_pacer_started; 12225 if (delay_calc >= bbr->r_ctl.rc_last_delay_val) 12226 delay_calc -= bbr->r_ctl.rc_last_delay_val; 12227 else 12228 delay_calc = 0; 12229 } 12230 /* Mark that we have called bbr_output(). */ 12231 if ((bbr->r_timer_override) || 12232 (tp->t_flags & TF_FORCEDATA) || 12233 (tp->t_state < TCPS_ESTABLISHED)) { 12234 /* Timeouts or early states are exempt */ 12235 if (inp->inp_in_hpts) 12236 tcp_hpts_remove(inp, HPTS_REMOVE_OUTPUT); 12237 } else if (inp->inp_in_hpts) { 12238 if ((bbr->r_ctl.rc_last_delay_val) && 12239 (bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) && 12240 delay_calc) { 12241 /* 12242 * We were being paced for output and the delay has 12243 * already exceeded when we were supposed to be 12244 * called, lets go ahead and pull out of the hpts 12245 * and call output. 12246 */ 12247 counter_u64_add(bbr_out_size[TCP_MSS_ACCT_LATE], 1); 12248 bbr->r_ctl.rc_last_delay_val = 0; 12249 tcp_hpts_remove(inp, HPTS_REMOVE_OUTPUT); 12250 } else if (tp->t_state == TCPS_CLOSED) { 12251 bbr->r_ctl.rc_last_delay_val = 0; 12252 tcp_hpts_remove(inp, HPTS_REMOVE_OUTPUT); 12253 } else { 12254 /* 12255 * On the hpts, you shall not pass! even if ACKNOW 12256 * is on, we will when the hpts fires, unless of 12257 * course we are overdue. 12258 */ 12259 counter_u64_add(bbr_out_size[TCP_MSS_ACCT_INPACE], 1); 12260 return (0); 12261 } 12262 } 12263 bbr->rc_cwnd_limited = 0; 12264 if (bbr->r_ctl.rc_last_delay_val) { 12265 /* recalculate the real delay and deal with over/under */ 12266 if (SEQ_GT(cts, bbr->rc_pacer_started)) 12267 delay_calc = cts - bbr->rc_pacer_started; 12268 else 12269 delay_calc = 0; 12270 if (delay_calc >= bbr->r_ctl.rc_last_delay_val) 12271 /* Setup the delay which will be added in */ 12272 delay_calc -= bbr->r_ctl.rc_last_delay_val; 12273 else { 12274 /* 12275 * We are early setup to adjust 12276 * our slot time. 12277 */ 12278 uint64_t merged_val; 12279 12280 bbr->r_ctl.rc_agg_early += (bbr->r_ctl.rc_last_delay_val - delay_calc); 12281 bbr->r_agg_early_set = 1; 12282 if (bbr->r_ctl.rc_hptsi_agg_delay) { 12283 if (bbr->r_ctl.rc_hptsi_agg_delay >= bbr->r_ctl.rc_agg_early) { 12284 /* Nope our previous late cancels out the early */ 12285 bbr->r_ctl.rc_hptsi_agg_delay -= bbr->r_ctl.rc_agg_early; 12286 bbr->r_agg_early_set = 0; 12287 bbr->r_ctl.rc_agg_early = 0; 12288 } else { 12289 bbr->r_ctl.rc_agg_early -= bbr->r_ctl.rc_hptsi_agg_delay; 12290 bbr->r_ctl.rc_hptsi_agg_delay = 0; 12291 } 12292 } 12293 merged_val = bbr->rc_pacer_started; 12294 merged_val <<= 32; 12295 merged_val |= bbr->r_ctl.rc_last_delay_val; 12296 bbr_log_pacing_delay_calc(bbr, inp->inp_hpts_calls, 12297 bbr->r_ctl.rc_agg_early, cts, delay_calc, merged_val, 12298 bbr->r_agg_early_set, 3); 12299 bbr->r_ctl.rc_last_delay_val = 0; 12300 BBR_STAT_INC(bbr_early); 12301 delay_calc = 0; 12302 } 12303 } else { 12304 /* We were not delayed due to hptsi */ 12305 if (bbr->r_agg_early_set) 12306 bbr->r_ctl.rc_agg_early = 0; 12307 bbr->r_agg_early_set = 0; 12308 delay_calc = 0; 12309 } 12310 if (delay_calc) { 12311 /* 12312 * We had a hptsi delay which means we are falling behind on 12313 * sending at the expected rate. Calculate an extra amount 12314 * of data we can send, if any, to put us back on track. 12315 */ 12316 if ((bbr->r_ctl.rc_hptsi_agg_delay + delay_calc) < bbr->r_ctl.rc_hptsi_agg_delay) 12317 bbr->r_ctl.rc_hptsi_agg_delay = 0xffffffff; 12318 else 12319 bbr->r_ctl.rc_hptsi_agg_delay += delay_calc; 12320 } 12321 sendwin = min(tp->snd_wnd, tp->snd_cwnd); 12322 if ((tp->snd_una == tp->snd_max) && 12323 (bbr->rc_bbr_state != BBR_STATE_IDLE_EXIT) && 12324 (sbavail(sb))) { 12325 /* 12326 * Ok we have been idle with nothing outstanding 12327 * we possibly need to start fresh with either a new 12328 * suite of states or a fast-ramp up. 12329 */ 12330 bbr_restart_after_idle(bbr, 12331 cts, bbr_calc_time(cts, bbr->r_ctl.rc_went_idle_time)); 12332 } 12333 /* 12334 * Now was there a hptsi delay where we are behind? We only count 12335 * being behind if: a) We are not in recovery. b) There was a delay. 12336 * <and> c) We had room to send something. 12337 * 12338 */ 12339 hpts_calling = inp->inp_hpts_calls; 12340 inp->inp_hpts_calls = 0; 12341 if (bbr->r_ctl.rc_hpts_flags & PACE_TMR_MASK) { 12342 if (bbr_process_timers(tp, bbr, cts, hpts_calling)) { 12343 counter_u64_add(bbr_out_size[TCP_MSS_ACCT_ATIMER], 1); 12344 return (0); 12345 } 12346 } 12347 bbr->rc_inp->inp_flags2 &= ~INP_MBUF_QUEUE_READY; 12348 if (hpts_calling && 12349 (bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT)) { 12350 bbr->r_ctl.rc_last_delay_val = 0; 12351 } 12352 bbr->r_timer_override = 0; 12353 bbr->r_wanted_output = 0; 12354 /* 12355 * For TFO connections in SYN_RECEIVED, only allow the initial 12356 * SYN|ACK and those sent by the retransmit timer. 12357 */ 12358 if (IS_FASTOPEN(tp->t_flags) && 12359 ((tp->t_state == TCPS_SYN_RECEIVED) || 12360 (tp->t_state == TCPS_SYN_SENT)) && 12361 SEQ_GT(tp->snd_max, tp->snd_una) && /* inital SYN or SYN|ACK sent */ 12362 (tp->t_rxtshift == 0)) { /* not a retransmit */ 12363 return (0); 12364 } 12365 /* 12366 * Before sending anything check for a state update. For hpts 12367 * calling without input this is important. If its input calling 12368 * then this was already done. 12369 */ 12370 if (bbr->rc_use_google == 0) 12371 bbr_check_bbr_for_state(bbr, cts, __LINE__, 0); 12372 again: 12373 /* 12374 * If we've recently taken a timeout, snd_max will be greater than 12375 * snd_max. BBR in general does not pay much attention to snd_nxt 12376 * for historic reasons the persist timer still uses it. This means 12377 * we have to look at it. All retransmissions that are not persits 12378 * use the rsm that needs to be sent so snd_nxt is ignored. At the 12379 * end of this routine we pull snd_nxt always up to snd_max. 12380 */ 12381 doing_tlp = 0; 12382 #ifdef BBR_INVARIANTS 12383 doing_retran_from = picked_up_retran = 0; 12384 #endif 12385 error = 0; 12386 tso = 0; 12387 slot = 0; 12388 mtu = 0; 12389 sendwin = min(tp->snd_wnd, tp->snd_cwnd); 12390 sb_offset = tp->snd_max - tp->snd_una; 12391 flags = tcp_outflags[tp->t_state]; 12392 sack_rxmit = 0; 12393 len = 0; 12394 rsm = NULL; 12395 if (flags & TH_RST) { 12396 SOCKBUF_LOCK(sb); 12397 goto send; 12398 } 12399 recheck_resend: 12400 while (bbr->r_ctl.rc_free_cnt < bbr_min_req_free) { 12401 /* We need to always have one in reserve */ 12402 rsm = bbr_alloc(bbr); 12403 if (rsm == NULL) { 12404 error = ENOMEM; 12405 /* Lie to get on the hpts */ 12406 tot_len = tp->t_maxseg; 12407 if (hpts_calling) 12408 /* Retry in a ms */ 12409 slot = 1001; 12410 goto just_return_nolock; 12411 } 12412 TAILQ_INSERT_TAIL(&bbr->r_ctl.rc_free, rsm, r_next); 12413 bbr->r_ctl.rc_free_cnt++; 12414 rsm = NULL; 12415 } 12416 /* What do we send, a resend? */ 12417 if (bbr->r_ctl.rc_resend == NULL) { 12418 /* Check for rack timeout */ 12419 bbr->r_ctl.rc_resend = bbr_check_recovery_mode(tp, bbr, cts); 12420 if (bbr->r_ctl.rc_resend) { 12421 #ifdef BBR_INVARIANTS 12422 picked_up_retran = 1; 12423 #endif 12424 bbr_cong_signal(tp, NULL, CC_NDUPACK, bbr->r_ctl.rc_resend); 12425 } 12426 } 12427 if (bbr->r_ctl.rc_resend) { 12428 rsm = bbr->r_ctl.rc_resend; 12429 #ifdef BBR_INVARIANTS 12430 doing_retran_from = 1; 12431 #endif 12432 /* Remove any TLP flags its a RACK or T-O */ 12433 rsm->r_flags &= ~BBR_TLP; 12434 bbr->r_ctl.rc_resend = NULL; 12435 if (SEQ_LT(rsm->r_start, tp->snd_una)) { 12436 #ifdef BBR_INVARIANTS 12437 panic("Huh, tp:%p bbr:%p rsm:%p start:%u < snd_una:%u\n", 12438 tp, bbr, rsm, rsm->r_start, tp->snd_una); 12439 goto recheck_resend; 12440 #else 12441 /* TSNH */ 12442 rsm = NULL; 12443 goto recheck_resend; 12444 #endif 12445 } 12446 rtr_cnt++; 12447 if (rsm->r_flags & BBR_HAS_SYN) { 12448 /* Only retransmit a SYN by itself */ 12449 len = 0; 12450 if ((flags & TH_SYN) == 0) { 12451 /* Huh something is wrong */ 12452 rsm->r_start++; 12453 if (rsm->r_start == rsm->r_end) { 12454 /* Clean it up, somehow we missed the ack? */ 12455 bbr_log_syn(tp, NULL); 12456 } else { 12457 /* TFO with data? */ 12458 rsm->r_flags &= ~BBR_HAS_SYN; 12459 len = rsm->r_end - rsm->r_start; 12460 } 12461 } else { 12462 /* Retransmitting SYN */ 12463 rsm = NULL; 12464 SOCKBUF_LOCK(sb); 12465 goto send; 12466 } 12467 } else 12468 len = rsm->r_end - rsm->r_start; 12469 if ((bbr->rc_resends_use_tso == 0) && 12470 #ifdef KERN_TLS 12471 ((sb->sb_flags & SB_TLS_IFNET) == 0) && 12472 #endif 12473 (len > maxseg)) { 12474 len = maxseg; 12475 more_to_rxt = 1; 12476 } 12477 sb_offset = rsm->r_start - tp->snd_una; 12478 if (len > 0) { 12479 sack_rxmit = 1; 12480 TCPSTAT_INC(tcps_sack_rexmits); 12481 TCPSTAT_ADD(tcps_sack_rexmit_bytes, 12482 min(len, maxseg)); 12483 } else { 12484 /* I dont think this can happen */ 12485 rsm = NULL; 12486 goto recheck_resend; 12487 } 12488 BBR_STAT_INC(bbr_resends_set); 12489 } else if (bbr->r_ctl.rc_tlp_send) { 12490 /* 12491 * Tail loss probe 12492 */ 12493 doing_tlp = 1; 12494 rsm = bbr->r_ctl.rc_tlp_send; 12495 bbr->r_ctl.rc_tlp_send = NULL; 12496 sack_rxmit = 1; 12497 len = rsm->r_end - rsm->r_start; 12498 rtr_cnt++; 12499 if ((bbr->rc_resends_use_tso == 0) && (len > maxseg)) 12500 len = maxseg; 12501 12502 if (SEQ_GT(tp->snd_una, rsm->r_start)) { 12503 #ifdef BBR_INVARIANTS 12504 panic("tp:%p bbc:%p snd_una:%u rsm:%p r_start:%u", 12505 tp, bbr, tp->snd_una, rsm, rsm->r_start); 12506 #else 12507 /* TSNH */ 12508 rsm = NULL; 12509 goto recheck_resend; 12510 #endif 12511 } 12512 sb_offset = rsm->r_start - tp->snd_una; 12513 BBR_STAT_INC(bbr_tlp_set); 12514 } 12515 /* 12516 * Enforce a connection sendmap count limit if set 12517 * as long as we are not retransmiting. 12518 */ 12519 if ((rsm == NULL) && 12520 (bbr_tcp_map_entries_limit > 0) && 12521 (bbr->r_ctl.rc_num_maps_alloced >= bbr_tcp_map_entries_limit)) { 12522 BBR_STAT_INC(bbr_alloc_limited); 12523 if (!bbr->alloc_limit_reported) { 12524 bbr->alloc_limit_reported = 1; 12525 BBR_STAT_INC(bbr_alloc_limited_conns); 12526 } 12527 goto just_return_nolock; 12528 } 12529 #ifdef BBR_INVARIANTS 12530 if (rsm && SEQ_LT(rsm->r_start, tp->snd_una)) { 12531 panic("tp:%p bbr:%p rsm:%p sb_offset:%u len:%u", 12532 tp, bbr, rsm, sb_offset, len); 12533 } 12534 #endif 12535 /* 12536 * Get standard flags, and add SYN or FIN if requested by 'hidden' 12537 * state flags. 12538 */ 12539 if (tp->t_flags & TF_NEEDFIN && (rsm == NULL)) 12540 flags |= TH_FIN; 12541 if (tp->t_flags & TF_NEEDSYN) 12542 flags |= TH_SYN; 12543 12544 if (rsm && (rsm->r_flags & BBR_HAS_FIN)) { 12545 /* we are retransmitting the fin */ 12546 len--; 12547 if (len) { 12548 /* 12549 * When retransmitting data do *not* include the 12550 * FIN. This could happen from a TLP probe if we 12551 * allowed data with a FIN. 12552 */ 12553 flags &= ~TH_FIN; 12554 } 12555 } else if (rsm) { 12556 if (flags & TH_FIN) 12557 flags &= ~TH_FIN; 12558 } 12559 if ((sack_rxmit == 0) && (prefetch_rsm == 0)) { 12560 void *end_rsm; 12561 12562 end_rsm = TAILQ_LAST_FAST(&bbr->r_ctl.rc_tmap, bbr_sendmap, r_tnext); 12563 if (end_rsm) 12564 kern_prefetch(end_rsm, &prefetch_rsm); 12565 prefetch_rsm = 1; 12566 } 12567 SOCKBUF_LOCK(sb); 12568 /* 12569 * If in persist timeout with window of 0, send 1 byte. Otherwise, 12570 * if window is small but nonzero and time TF_SENTFIN expired, we 12571 * will send what we can and go to transmit state. 12572 */ 12573 if (tp->t_flags & TF_FORCEDATA) { 12574 if ((sendwin == 0) || (sendwin <= (tp->snd_max - tp->snd_una))) { 12575 /* 12576 * If we still have some data to send, then clear 12577 * the FIN bit. Usually this would happen below 12578 * when it realizes that we aren't sending all the 12579 * data. However, if we have exactly 1 byte of 12580 * unsent data, then it won't clear the FIN bit 12581 * below, and if we are in persist state, we wind up 12582 * sending the packet without recording that we sent 12583 * the FIN bit. 12584 * 12585 * We can't just blindly clear the FIN bit, because 12586 * if we don't have any more data to send then the 12587 * probe will be the FIN itself. 12588 */ 12589 if (sb_offset < sbused(sb)) 12590 flags &= ~TH_FIN; 12591 sendwin = 1; 12592 } else { 12593 if ((bbr->rc_in_persist != 0) && 12594 (tp->snd_wnd >= min((bbr->r_ctl.rc_high_rwnd/2), 12595 bbr_minseg(bbr)))) { 12596 /* Exit persists if there is space */ 12597 bbr_exit_persist(tp, bbr, cts, __LINE__); 12598 } 12599 if (rsm == NULL) { 12600 /* 12601 * If we are dropping persist mode then we 12602 * need to correct sb_offset if not a 12603 * retransmit. 12604 */ 12605 sb_offset = tp->snd_max - tp->snd_una; 12606 } 12607 } 12608 } 12609 /* 12610 * If snd_nxt == snd_max and we have transmitted a FIN, the 12611 * sb_offset will be > 0 even if so_snd.sb_cc is 0, resulting in a 12612 * negative length. This can also occur when TCP opens up its 12613 * congestion window while receiving additional duplicate acks after 12614 * fast-retransmit because TCP will reset snd_nxt to snd_max after 12615 * the fast-retransmit. 12616 * 12617 * In the normal retransmit-FIN-only case, however, snd_nxt will be 12618 * set to snd_una, the sb_offset will be 0, and the length may wind 12619 * up 0. 12620 * 12621 * If sack_rxmit is true we are retransmitting from the scoreboard 12622 * in which case len is already set. 12623 */ 12624 if (sack_rxmit == 0) { 12625 uint32_t avail; 12626 12627 avail = sbavail(sb); 12628 if (SEQ_GT(tp->snd_max, tp->snd_una)) 12629 sb_offset = tp->snd_max - tp->snd_una; 12630 else 12631 sb_offset = 0; 12632 if (bbr->rc_tlp_new_data) { 12633 /* TLP is forcing out new data */ 12634 uint32_t tlplen; 12635 12636 doing_tlp = 1; 12637 tlplen = maxseg; 12638 12639 if (tlplen > (uint32_t)(avail - sb_offset)) { 12640 tlplen = (uint32_t)(avail - sb_offset); 12641 } 12642 if (tlplen > tp->snd_wnd) { 12643 len = tp->snd_wnd; 12644 } else { 12645 len = tlplen; 12646 } 12647 bbr->rc_tlp_new_data = 0; 12648 } else { 12649 what_we_can = len = bbr_what_can_we_send(tp, bbr, sendwin, avail, sb_offset, cts); 12650 if ((len < p_maxseg) && 12651 (bbr->rc_in_persist == 0) && 12652 (ctf_outstanding(tp) >= (2 * p_maxseg)) && 12653 ((avail - sb_offset) >= p_maxseg)) { 12654 /* 12655 * We are not completing whats in the socket 12656 * buffer (i.e. there is at least a segment 12657 * waiting to send) and we have 2 or more 12658 * segments outstanding. There is no sense 12659 * of sending a little piece. Lets defer and 12660 * and wait until we can send a whole 12661 * segment. 12662 */ 12663 len = 0; 12664 } 12665 if ((tp->t_flags & TF_FORCEDATA) && (bbr->rc_in_persist)) { 12666 /* 12667 * We are in persists, figure out if 12668 * a retransmit is available (maybe the previous 12669 * persists we sent) or if we have to send new 12670 * data. 12671 */ 12672 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map); 12673 if (rsm) { 12674 len = rsm->r_end - rsm->r_start; 12675 if (rsm->r_flags & BBR_HAS_FIN) 12676 len--; 12677 if ((bbr->rc_resends_use_tso == 0) && (len > maxseg)) 12678 len = maxseg; 12679 if (len > 1) 12680 BBR_STAT_INC(bbr_persist_reneg); 12681 /* 12682 * XXXrrs we could force the len to 12683 * 1 byte here to cause the chunk to 12684 * split apart.. but that would then 12685 * mean we always retransmit it as 12686 * one byte even after the window 12687 * opens. 12688 */ 12689 sack_rxmit = 1; 12690 sb_offset = rsm->r_start - tp->snd_una; 12691 } else { 12692 /* 12693 * First time through in persists or peer 12694 * acked our one byte. Though we do have 12695 * to have something in the sb. 12696 */ 12697 len = 1; 12698 sb_offset = 0; 12699 if (avail == 0) 12700 len = 0; 12701 } 12702 } 12703 } 12704 } 12705 if (prefetch_so_done == 0) { 12706 kern_prefetch(so, &prefetch_so_done); 12707 prefetch_so_done = 1; 12708 } 12709 /* 12710 * Lop off SYN bit if it has already been sent. However, if this is 12711 * SYN-SENT state and if segment contains data and if we don't know 12712 * that foreign host supports TAO, suppress sending segment. 12713 */ 12714 if ((flags & TH_SYN) && (rsm == NULL) && 12715 SEQ_GT(tp->snd_max, tp->snd_una)) { 12716 if (tp->t_state != TCPS_SYN_RECEIVED) 12717 flags &= ~TH_SYN; 12718 /* 12719 * When sending additional segments following a TFO SYN|ACK, 12720 * do not include the SYN bit. 12721 */ 12722 if (IS_FASTOPEN(tp->t_flags) && 12723 (tp->t_state == TCPS_SYN_RECEIVED)) 12724 flags &= ~TH_SYN; 12725 sb_offset--, len++; 12726 if (sbavail(sb) == 0) 12727 len = 0; 12728 } else if ((flags & TH_SYN) && rsm) { 12729 /* 12730 * Subtract one from the len for the SYN being 12731 * retransmitted. 12732 */ 12733 len--; 12734 } 12735 /* 12736 * Be careful not to send data and/or FIN on SYN segments. This 12737 * measure is needed to prevent interoperability problems with not 12738 * fully conformant TCP implementations. 12739 */ 12740 if ((flags & TH_SYN) && (tp->t_flags & TF_NOOPT)) { 12741 len = 0; 12742 flags &= ~TH_FIN; 12743 } 12744 /* 12745 * On TFO sockets, ensure no data is sent in the following cases: 12746 * 12747 * - When retransmitting SYN|ACK on a passively-created socket 12748 * - When retransmitting SYN on an actively created socket 12749 * - When sending a zero-length cookie (cookie request) on an 12750 * actively created socket 12751 * - When the socket is in the CLOSED state (RST is being sent) 12752 */ 12753 if (IS_FASTOPEN(tp->t_flags) && 12754 (((flags & TH_SYN) && (tp->t_rxtshift > 0)) || 12755 ((tp->t_state == TCPS_SYN_SENT) && 12756 (tp->t_tfo_client_cookie_len == 0)) || 12757 (flags & TH_RST))) { 12758 len = 0; 12759 sack_rxmit = 0; 12760 rsm = NULL; 12761 } 12762 /* Without fast-open there should never be data sent on a SYN */ 12763 if ((flags & TH_SYN) && (!IS_FASTOPEN(tp->t_flags))) 12764 len = 0; 12765 if (len <= 0) { 12766 /* 12767 * If FIN has been sent but not acked, but we haven't been 12768 * called to retransmit, len will be < 0. Otherwise, window 12769 * shrank after we sent into it. If window shrank to 0, 12770 * cancel pending retransmit, pull snd_nxt back to (closed) 12771 * window, and set the persist timer if it isn't already 12772 * going. If the window didn't close completely, just wait 12773 * for an ACK. 12774 * 12775 * We also do a general check here to ensure that we will 12776 * set the persist timer when we have data to send, but a 12777 * 0-byte window. This makes sure the persist timer is set 12778 * even if the packet hits one of the "goto send" lines 12779 * below. 12780 */ 12781 len = 0; 12782 if ((tp->snd_wnd == 0) && 12783 (TCPS_HAVEESTABLISHED(tp->t_state)) && 12784 (tp->snd_una == tp->snd_max) && 12785 (sb_offset < (int)sbavail(sb))) { 12786 /* 12787 * Not enough room in the rwnd to send 12788 * a paced segment out. 12789 */ 12790 bbr_enter_persist(tp, bbr, cts, __LINE__); 12791 } 12792 } else if ((rsm == NULL) && 12793 (doing_tlp == 0) && 12794 (len < bbr->r_ctl.rc_pace_max_segs)) { 12795 /* 12796 * We are not sending a full segment for 12797 * some reason. Should we not send anything (think 12798 * sws or persists)? 12799 */ 12800 if ((tp->snd_wnd < min((bbr->r_ctl.rc_high_rwnd/2), bbr_minseg(bbr))) && 12801 (TCPS_HAVEESTABLISHED(tp->t_state)) && 12802 (len < (int)(sbavail(sb) - sb_offset))) { 12803 /* 12804 * Here the rwnd is less than 12805 * the pacing size, this is not a retransmit, 12806 * we are established and 12807 * the send is not the last in the socket buffer 12808 * lets not send, and possibly enter persists. 12809 */ 12810 len = 0; 12811 if (tp->snd_max == tp->snd_una) 12812 bbr_enter_persist(tp, bbr, cts, __LINE__); 12813 } else if ((tp->snd_cwnd >= bbr->r_ctl.rc_pace_max_segs) && 12814 (ctf_flight_size(tp, (bbr->r_ctl.rc_sacked + 12815 bbr->r_ctl.rc_lost_bytes)) > (2 * maxseg)) && 12816 (len < (int)(sbavail(sb) - sb_offset)) && 12817 (len < bbr_minseg(bbr))) { 12818 /* 12819 * Here we are not retransmitting, and 12820 * the cwnd is not so small that we could 12821 * not send at least a min size (rxt timer 12822 * not having gone off), We have 2 segments or 12823 * more already in flight, its not the tail end 12824 * of the socket buffer and the cwnd is blocking 12825 * us from sending out minimum pacing segment size. 12826 * Lets not send anything. 12827 */ 12828 bbr->rc_cwnd_limited = 1; 12829 len = 0; 12830 } else if (((tp->snd_wnd - ctf_outstanding(tp)) < 12831 min((bbr->r_ctl.rc_high_rwnd/2), bbr_minseg(bbr))) && 12832 (ctf_flight_size(tp, (bbr->r_ctl.rc_sacked + 12833 bbr->r_ctl.rc_lost_bytes)) > (2 * maxseg)) && 12834 (len < (int)(sbavail(sb) - sb_offset)) && 12835 (TCPS_HAVEESTABLISHED(tp->t_state))) { 12836 /* 12837 * Here we have a send window but we have 12838 * filled it up and we can't send another pacing segment. 12839 * We also have in flight more than 2 segments 12840 * and we are not completing the sb i.e. we allow 12841 * the last bytes of the sb to go out even if 12842 * its not a full pacing segment. 12843 */ 12844 len = 0; 12845 } 12846 } 12847 /* len will be >= 0 after this point. */ 12848 KASSERT(len >= 0, ("[%s:%d]: len < 0", __func__, __LINE__)); 12849 tcp_sndbuf_autoscale(tp, so, sendwin); 12850 /* 12851 * 12852 */ 12853 if (bbr->rc_in_persist && 12854 len && 12855 (rsm == NULL) && 12856 (len < min((bbr->r_ctl.rc_high_rwnd/2), bbr->r_ctl.rc_pace_max_segs))) { 12857 /* 12858 * We are in persist, not doing a retransmit and don't have enough space 12859 * yet to send a full TSO. So is it at the end of the sb 12860 * if so we need to send else nuke to 0 and don't send. 12861 */ 12862 int sbleft; 12863 if (sbavail(sb) > sb_offset) 12864 sbleft = sbavail(sb) - sb_offset; 12865 else 12866 sbleft = 0; 12867 if (sbleft >= min((bbr->r_ctl.rc_high_rwnd/2), bbr->r_ctl.rc_pace_max_segs)) { 12868 /* not at end of sb lets not send */ 12869 len = 0; 12870 } 12871 } 12872 /* 12873 * Decide if we can use TCP Segmentation Offloading (if supported by 12874 * hardware). 12875 * 12876 * TSO may only be used if we are in a pure bulk sending state. The 12877 * presence of TCP-MD5, SACK retransmits, SACK advertizements and IP 12878 * options prevent using TSO. With TSO the TCP header is the same 12879 * (except for the sequence number) for all generated packets. This 12880 * makes it impossible to transmit any options which vary per 12881 * generated segment or packet. 12882 * 12883 * IPv4 handling has a clear separation of ip options and ip header 12884 * flags while IPv6 combines both in in6p_outputopts. ip6_optlen() 12885 * does the right thing below to provide length of just ip options 12886 * and thus checking for ipoptlen is enough to decide if ip options 12887 * are present. 12888 */ 12889 #ifdef INET6 12890 if (isipv6) 12891 ipoptlen = ip6_optlen(inp); 12892 else 12893 #endif 12894 if (inp->inp_options) 12895 ipoptlen = inp->inp_options->m_len - 12896 offsetof(struct ipoption, ipopt_list); 12897 else 12898 ipoptlen = 0; 12899 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 12900 /* 12901 * Pre-calculate here as we save another lookup into the darknesses 12902 * of IPsec that way and can actually decide if TSO is ok. 12903 */ 12904 #ifdef INET6 12905 if (isipv6 && IPSEC_ENABLED(ipv6)) 12906 ipsec_optlen = IPSEC_HDRSIZE(ipv6, inp); 12907 #ifdef INET 12908 else 12909 #endif 12910 #endif /* INET6 */ 12911 #ifdef INET 12912 if (IPSEC_ENABLED(ipv4)) 12913 ipsec_optlen = IPSEC_HDRSIZE(ipv4, inp); 12914 #endif /* INET */ 12915 #endif /* IPSEC */ 12916 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 12917 ipoptlen += ipsec_optlen; 12918 #endif 12919 if ((tp->t_flags & TF_TSO) && V_tcp_do_tso && 12920 (len > maxseg) && 12921 (tp->t_port == 0) && 12922 ((tp->t_flags & TF_SIGNATURE) == 0) && 12923 tp->rcv_numsacks == 0 && 12924 ipoptlen == 0) 12925 tso = 1; 12926 12927 recwin = min(max(sbspace(&so->so_rcv), 0), 12928 TCP_MAXWIN << tp->rcv_scale); 12929 /* 12930 * Sender silly window avoidance. We transmit under the following 12931 * conditions when len is non-zero: 12932 * 12933 * - We have a full segment (or more with TSO) - This is the last 12934 * buffer in a write()/send() and we are either idle or running 12935 * NODELAY - we've timed out (e.g. persist timer) - we have more 12936 * then 1/2 the maximum send window's worth of data (receiver may be 12937 * limited the window size) - we need to retransmit 12938 */ 12939 if (rsm) 12940 goto send; 12941 if (len) { 12942 if (sack_rxmit) 12943 goto send; 12944 if (len >= p_maxseg) 12945 goto send; 12946 /* 12947 * NOTE! on localhost connections an 'ack' from the remote 12948 * end may occur synchronously with the output and cause us 12949 * to flush a buffer queued with moretocome. XXX 12950 * 12951 */ 12952 if (((tp->t_flags & TF_MORETOCOME) == 0) && /* normal case */ 12953 ((tp->t_flags & TF_NODELAY) || 12954 ((uint32_t)len + (uint32_t)sb_offset) >= sbavail(&so->so_snd)) && 12955 (tp->t_flags & TF_NOPUSH) == 0) { 12956 goto send; 12957 } 12958 if ((tp->snd_una == tp->snd_max) && len) { /* Nothing outstanding */ 12959 goto send; 12960 } 12961 if (tp->t_flags & TF_FORCEDATA) { /* typ. timeout case */ 12962 goto send; 12963 } 12964 if (len >= tp->max_sndwnd / 2 && tp->max_sndwnd > 0) { 12965 goto send; 12966 } 12967 } 12968 /* 12969 * Sending of standalone window updates. 12970 * 12971 * Window updates are important when we close our window due to a 12972 * full socket buffer and are opening it again after the application 12973 * reads data from it. Once the window has opened again and the 12974 * remote end starts to send again the ACK clock takes over and 12975 * provides the most current window information. 12976 * 12977 * We must avoid the silly window syndrome whereas every read from 12978 * the receive buffer, no matter how small, causes a window update 12979 * to be sent. We also should avoid sending a flurry of window 12980 * updates when the socket buffer had queued a lot of data and the 12981 * application is doing small reads. 12982 * 12983 * Prevent a flurry of pointless window updates by only sending an 12984 * update when we can increase the advertized window by more than 12985 * 1/4th of the socket buffer capacity. When the buffer is getting 12986 * full or is very small be more aggressive and send an update 12987 * whenever we can increase by two mss sized segments. In all other 12988 * situations the ACK's to new incoming data will carry further 12989 * window increases. 12990 * 12991 * Don't send an independent window update if a delayed ACK is 12992 * pending (it will get piggy-backed on it) or the remote side 12993 * already has done a half-close and won't send more data. Skip 12994 * this if the connection is in T/TCP half-open state. 12995 */ 12996 if (recwin > 0 && !(tp->t_flags & TF_NEEDSYN) && 12997 !(tp->t_flags & TF_DELACK) && 12998 !TCPS_HAVERCVDFIN(tp->t_state)) { 12999 /* Check to see if we should do a window update */ 13000 if (bbr_window_update_needed(tp, so, recwin, maxseg)) 13001 goto send; 13002 } 13003 /* 13004 * Send if we owe the peer an ACK, RST, SYN, or urgent data. ACKNOW 13005 * is also a catch-all for the retransmit timer timeout case. 13006 */ 13007 if (tp->t_flags & TF_ACKNOW) { 13008 goto send; 13009 } 13010 if (((flags & TH_SYN) && (tp->t_flags & TF_NEEDSYN) == 0)) { 13011 goto send; 13012 } 13013 if (SEQ_GT(tp->snd_up, tp->snd_una)) { 13014 goto send; 13015 } 13016 /* 13017 * If our state indicates that FIN should be sent and we have not 13018 * yet done so, then we need to send. 13019 */ 13020 if (flags & TH_FIN && 13021 ((tp->t_flags & TF_SENTFIN) == 0)) { 13022 goto send; 13023 } 13024 /* 13025 * No reason to send a segment, just return. 13026 */ 13027 just_return: 13028 SOCKBUF_UNLOCK(sb); 13029 just_return_nolock: 13030 if (tot_len) 13031 slot = bbr_get_pacing_delay(bbr, bbr->r_ctl.rc_bbr_hptsi_gain, tot_len, cts, 0); 13032 if (bbr->rc_no_pacing) 13033 slot = 0; 13034 if (tot_len == 0) { 13035 if ((ctf_outstanding(tp) + min((bbr->r_ctl.rc_high_rwnd/2), bbr_minseg(bbr))) >= 13036 tp->snd_wnd) { 13037 BBR_STAT_INC(bbr_rwnd_limited); 13038 app_limited = BBR_JR_RWND_LIMITED; 13039 bbr_cwnd_limiting(tp, bbr, ctf_outstanding(tp)); 13040 if ((bbr->rc_in_persist == 0) && 13041 TCPS_HAVEESTABLISHED(tp->t_state) && 13042 (tp->snd_max == tp->snd_una) && 13043 sbavail(&tp->t_inpcb->inp_socket->so_snd)) { 13044 /* No send window.. we must enter persist */ 13045 bbr_enter_persist(tp, bbr, bbr->r_ctl.rc_rcvtime, __LINE__); 13046 } 13047 } else if (ctf_outstanding(tp) >= sbavail(sb)) { 13048 BBR_STAT_INC(bbr_app_limited); 13049 app_limited = BBR_JR_APP_LIMITED; 13050 bbr_cwnd_limiting(tp, bbr, ctf_outstanding(tp)); 13051 } else if ((ctf_flight_size(tp, (bbr->r_ctl.rc_sacked + 13052 bbr->r_ctl.rc_lost_bytes)) + p_maxseg) >= tp->snd_cwnd) { 13053 BBR_STAT_INC(bbr_cwnd_limited); 13054 app_limited = BBR_JR_CWND_LIMITED; 13055 bbr_cwnd_limiting(tp, bbr, ctf_flight_size(tp, (bbr->r_ctl.rc_sacked + 13056 bbr->r_ctl.rc_lost_bytes))); 13057 bbr->rc_cwnd_limited = 1; 13058 } else { 13059 BBR_STAT_INC(bbr_app_limited); 13060 app_limited = BBR_JR_APP_LIMITED; 13061 bbr_cwnd_limiting(tp, bbr, ctf_outstanding(tp)); 13062 } 13063 bbr->r_ctl.rc_hptsi_agg_delay = 0; 13064 bbr->r_agg_early_set = 0; 13065 bbr->r_ctl.rc_agg_early = 0; 13066 bbr->r_ctl.rc_last_delay_val = 0; 13067 } else if (bbr->rc_use_google == 0) 13068 bbr_check_bbr_for_state(bbr, cts, __LINE__, 0); 13069 /* Are we app limited? */ 13070 if ((app_limited == BBR_JR_APP_LIMITED) || 13071 (app_limited == BBR_JR_RWND_LIMITED)) { 13072 /** 13073 * We are application limited. 13074 */ 13075 bbr->r_ctl.r_app_limited_until = (ctf_flight_size(tp, (bbr->r_ctl.rc_sacked + 13076 bbr->r_ctl.rc_lost_bytes)) + bbr->r_ctl.rc_delivered); 13077 } 13078 if (tot_len == 0) 13079 counter_u64_add(bbr_out_size[TCP_MSS_ACCT_JUSTRET], 1); 13080 tp->t_flags &= ~TF_FORCEDATA; 13081 /* Dont update the time if we did not send */ 13082 bbr->r_ctl.rc_last_delay_val = 0; 13083 bbr->rc_output_starts_timer = 1; 13084 bbr_start_hpts_timer(bbr, tp, cts, 9, slot, tot_len); 13085 bbr_log_type_just_return(bbr, cts, tot_len, hpts_calling, app_limited, p_maxseg, len); 13086 if (SEQ_LT(tp->snd_nxt, tp->snd_max)) { 13087 /* Make sure snd_nxt is drug up */ 13088 tp->snd_nxt = tp->snd_max; 13089 } 13090 return (error); 13091 13092 send: 13093 if (doing_tlp == 0) { 13094 /* 13095 * Data not a TLP, and its not the rxt firing. If it is the 13096 * rxt firing, we want to leave the tlp_in_progress flag on 13097 * so we don't send another TLP. It has to be a rack timer 13098 * or normal send (response to acked data) to clear the tlp 13099 * in progress flag. 13100 */ 13101 bbr->rc_tlp_in_progress = 0; 13102 bbr->rc_tlp_rtx_out = 0; 13103 } else { 13104 /* 13105 * Its a TLP. 13106 */ 13107 bbr->rc_tlp_in_progress = 1; 13108 } 13109 bbr_timer_cancel(bbr, __LINE__, cts); 13110 if (rsm == NULL) { 13111 if (sbused(sb) > 0) { 13112 /* 13113 * This is sub-optimal. We only send a stand alone 13114 * FIN on its own segment. 13115 */ 13116 if (flags & TH_FIN) { 13117 flags &= ~TH_FIN; 13118 if ((len == 0) && ((tp->t_flags & TF_ACKNOW) == 0)) { 13119 /* Lets not send this */ 13120 slot = 0; 13121 goto just_return; 13122 } 13123 } 13124 } 13125 } else { 13126 /* 13127 * We do *not* send a FIN on a retransmit if it has data. 13128 * The if clause here where len > 1 should never come true. 13129 */ 13130 if ((len > 0) && 13131 (((rsm->r_flags & BBR_HAS_FIN) == 0) && 13132 (flags & TH_FIN))) { 13133 flags &= ~TH_FIN; 13134 len--; 13135 } 13136 } 13137 SOCKBUF_LOCK_ASSERT(sb); 13138 if (len > 0) { 13139 if ((tp->snd_una == tp->snd_max) && 13140 (bbr_calc_time(cts, bbr->r_ctl.rc_went_idle_time) >= bbr_rtt_probe_time)) { 13141 /* 13142 * This qualifies as a RTT_PROBE session since we 13143 * drop the data outstanding to nothing and waited 13144 * more than bbr_rtt_probe_time. 13145 */ 13146 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_WASIDLE, 0); 13147 bbr_set_reduced_rtt(bbr, cts, __LINE__); 13148 } 13149 if (len >= maxseg) 13150 tp->t_flags2 |= TF2_PLPMTU_MAXSEGSNT; 13151 else 13152 tp->t_flags2 &= ~TF2_PLPMTU_MAXSEGSNT; 13153 } 13154 /* 13155 * Before ESTABLISHED, force sending of initial options unless TCP 13156 * set not to do any options. NOTE: we assume that the IP/TCP header 13157 * plus TCP options always fit in a single mbuf, leaving room for a 13158 * maximum link header, i.e. max_linkhdr + sizeof (struct tcpiphdr) 13159 * + optlen <= MCLBYTES 13160 */ 13161 optlen = 0; 13162 #ifdef INET6 13163 if (isipv6) 13164 hdrlen = sizeof(struct ip6_hdr) + sizeof(struct tcphdr); 13165 else 13166 #endif 13167 hdrlen = sizeof(struct tcpiphdr); 13168 13169 /* 13170 * Compute options for segment. We only have to care about SYN and 13171 * established connection segments. Options for SYN-ACK segments 13172 * are handled in TCP syncache. 13173 */ 13174 to.to_flags = 0; 13175 local_options = 0; 13176 if ((tp->t_flags & TF_NOOPT) == 0) { 13177 /* Maximum segment size. */ 13178 if (flags & TH_SYN) { 13179 to.to_mss = tcp_mssopt(&inp->inp_inc); 13180 #ifdef NETFLIX_TCPOUDP 13181 if (tp->t_port) 13182 to.to_mss -= V_tcp_udp_tunneling_overhead; 13183 #endif 13184 to.to_flags |= TOF_MSS; 13185 /* 13186 * On SYN or SYN|ACK transmits on TFO connections, 13187 * only include the TFO option if it is not a 13188 * retransmit, as the presence of the TFO option may 13189 * have caused the original SYN or SYN|ACK to have 13190 * been dropped by a middlebox. 13191 */ 13192 if (IS_FASTOPEN(tp->t_flags) && 13193 (tp->t_rxtshift == 0)) { 13194 if (tp->t_state == TCPS_SYN_RECEIVED) { 13195 to.to_tfo_len = TCP_FASTOPEN_COOKIE_LEN; 13196 to.to_tfo_cookie = 13197 (u_int8_t *)&tp->t_tfo_cookie.server; 13198 to.to_flags |= TOF_FASTOPEN; 13199 wanted_cookie = 1; 13200 } else if (tp->t_state == TCPS_SYN_SENT) { 13201 to.to_tfo_len = 13202 tp->t_tfo_client_cookie_len; 13203 to.to_tfo_cookie = 13204 tp->t_tfo_cookie.client; 13205 to.to_flags |= TOF_FASTOPEN; 13206 wanted_cookie = 1; 13207 } 13208 } 13209 } 13210 /* Window scaling. */ 13211 if ((flags & TH_SYN) && (tp->t_flags & TF_REQ_SCALE)) { 13212 to.to_wscale = tp->request_r_scale; 13213 to.to_flags |= TOF_SCALE; 13214 } 13215 /* Timestamps. */ 13216 if ((tp->t_flags & TF_RCVD_TSTMP) || 13217 ((flags & TH_SYN) && (tp->t_flags & TF_REQ_TSTMP))) { 13218 to.to_tsval = tcp_tv_to_mssectick(&bbr->rc_tv) + tp->ts_offset; 13219 to.to_tsecr = tp->ts_recent; 13220 to.to_flags |= TOF_TS; 13221 local_options += TCPOLEN_TIMESTAMP + 2; 13222 } 13223 /* Set receive buffer autosizing timestamp. */ 13224 if (tp->rfbuf_ts == 0 && 13225 (so->so_rcv.sb_flags & SB_AUTOSIZE)) 13226 tp->rfbuf_ts = tcp_tv_to_mssectick(&bbr->rc_tv); 13227 /* Selective ACK's. */ 13228 if (flags & TH_SYN) 13229 to.to_flags |= TOF_SACKPERM; 13230 else if (TCPS_HAVEESTABLISHED(tp->t_state) && 13231 tp->rcv_numsacks > 0) { 13232 to.to_flags |= TOF_SACK; 13233 to.to_nsacks = tp->rcv_numsacks; 13234 to.to_sacks = (u_char *)tp->sackblks; 13235 } 13236 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 13237 /* TCP-MD5 (RFC2385). */ 13238 if (tp->t_flags & TF_SIGNATURE) 13239 to.to_flags |= TOF_SIGNATURE; 13240 #endif /* TCP_SIGNATURE */ 13241 13242 /* Processing the options. */ 13243 hdrlen += (optlen = tcp_addoptions(&to, opt)); 13244 /* 13245 * If we wanted a TFO option to be added, but it was unable 13246 * to fit, ensure no data is sent. 13247 */ 13248 if (IS_FASTOPEN(tp->t_flags) && wanted_cookie && 13249 !(to.to_flags & TOF_FASTOPEN)) 13250 len = 0; 13251 } 13252 #ifdef NETFLIX_TCPOUDP 13253 if (tp->t_port) { 13254 if (V_tcp_udp_tunneling_port == 0) { 13255 /* The port was removed?? */ 13256 SOCKBUF_UNLOCK(&so->so_snd); 13257 return (EHOSTUNREACH); 13258 } 13259 13260 hdrlen += sizeof(struct udphdr); 13261 } 13262 #endif 13263 #ifdef INET6 13264 if (isipv6) 13265 ipoptlen = ip6_optlen(tp->t_inpcb); 13266 else 13267 #endif 13268 if (tp->t_inpcb->inp_options) 13269 ipoptlen = tp->t_inpcb->inp_options->m_len - 13270 offsetof(struct ipoption, ipopt_list); 13271 else 13272 ipoptlen = 0; 13273 ipoptlen = 0; 13274 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 13275 ipoptlen += ipsec_optlen; 13276 #endif 13277 if (bbr->rc_last_options != local_options) { 13278 /* 13279 * Cache the options length this generally does not change 13280 * on a connection. We use this to calculate TSO. 13281 */ 13282 bbr->rc_last_options = local_options; 13283 } 13284 maxseg = tp->t_maxseg - (ipoptlen + optlen); 13285 p_maxseg = min(maxseg, pace_max_segs); 13286 /* 13287 * Adjust data length if insertion of options will bump the packet 13288 * length beyond the t_maxseg length. Clear the FIN bit because we 13289 * cut off the tail of the segment. 13290 */ 13291 #ifdef KERN_TLS 13292 /* force TSO for so TLS offload can get mss */ 13293 if (sb->sb_flags & SB_TLS_IFNET) { 13294 force_tso = 1; 13295 } 13296 #endif 13297 13298 if (len > maxseg) { 13299 if (len != 0 && (flags & TH_FIN)) { 13300 flags &= ~TH_FIN; 13301 } 13302 if (tso) { 13303 uint32_t moff; 13304 int32_t max_len; 13305 13306 /* extract TSO information */ 13307 if_hw_tsomax = tp->t_tsomax; 13308 if_hw_tsomaxsegcount = tp->t_tsomaxsegcount; 13309 if_hw_tsomaxsegsize = tp->t_tsomaxsegsize; 13310 KASSERT(ipoptlen == 0, 13311 ("%s: TSO can't do IP options", __func__)); 13312 13313 /* 13314 * Check if we should limit by maximum payload 13315 * length: 13316 */ 13317 if (if_hw_tsomax != 0) { 13318 /* compute maximum TSO length */ 13319 max_len = (if_hw_tsomax - hdrlen - 13320 max_linkhdr); 13321 if (max_len <= 0) { 13322 len = 0; 13323 } else if (len > max_len) { 13324 len = max_len; 13325 } 13326 } 13327 /* 13328 * Prevent the last segment from being fractional 13329 * unless the send sockbuf can be emptied: 13330 */ 13331 if (((sb_offset + len) < sbavail(sb)) && 13332 (hw_tls == 0)) { 13333 moff = len % (uint32_t)maxseg; 13334 if (moff != 0) { 13335 len -= moff; 13336 } 13337 } 13338 /* 13339 * In case there are too many small fragments don't 13340 * use TSO: 13341 */ 13342 if (len <= maxseg) { 13343 len = maxseg; 13344 tso = 0; 13345 } 13346 } else { 13347 /* Not doing TSO */ 13348 if (optlen + ipoptlen >= tp->t_maxseg) { 13349 /* 13350 * Since we don't have enough space to put 13351 * the IP header chain and the TCP header in 13352 * one packet as required by RFC 7112, don't 13353 * send it. Also ensure that at least one 13354 * byte of the payload can be put into the 13355 * TCP segment. 13356 */ 13357 SOCKBUF_UNLOCK(&so->so_snd); 13358 error = EMSGSIZE; 13359 sack_rxmit = 0; 13360 goto out; 13361 } 13362 len = maxseg; 13363 } 13364 } else { 13365 /* Not doing TSO */ 13366 if_hw_tsomaxsegcount = 0; 13367 tso = 0; 13368 } 13369 KASSERT(len + hdrlen + ipoptlen <= IP_MAXPACKET, 13370 ("%s: len > IP_MAXPACKET", __func__)); 13371 #ifdef DIAGNOSTIC 13372 #ifdef INET6 13373 if (max_linkhdr + hdrlen > MCLBYTES) 13374 #else 13375 if (max_linkhdr + hdrlen > MHLEN) 13376 #endif 13377 panic("tcphdr too big"); 13378 #endif 13379 /* 13380 * This KASSERT is here to catch edge cases at a well defined place. 13381 * Before, those had triggered (random) panic conditions further 13382 * down. 13383 */ 13384 #ifdef BBR_INVARIANTS 13385 if (sack_rxmit) { 13386 if (SEQ_LT(rsm->r_start, tp->snd_una)) { 13387 panic("RSM:%p TP:%p bbr:%p start:%u is < snd_una:%u", 13388 rsm, tp, bbr, rsm->r_start, tp->snd_una); 13389 } 13390 } 13391 #endif 13392 KASSERT(len >= 0, ("[%s:%d]: len < 0", __func__, __LINE__)); 13393 if ((len == 0) && 13394 (flags & TH_FIN) && 13395 (sbused(sb))) { 13396 /* 13397 * We have outstanding data, don't send a fin by itself!. 13398 */ 13399 slot = 0; 13400 goto just_return; 13401 } 13402 /* 13403 * Grab a header mbuf, attaching a copy of data to be transmitted, 13404 * and initialize the header from the template for sends on this 13405 * connection. 13406 */ 13407 if (len) { 13408 uint32_t moff; 13409 uint32_t orig_len; 13410 13411 /* 13412 * We place a limit on sending with hptsi. 13413 */ 13414 if ((rsm == NULL) && len > pace_max_segs) 13415 len = pace_max_segs; 13416 if (len <= maxseg) 13417 tso = 0; 13418 #ifdef INET6 13419 if (MHLEN < hdrlen + max_linkhdr) 13420 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); 13421 else 13422 #endif 13423 m = m_gethdr(M_NOWAIT, MT_DATA); 13424 13425 if (m == NULL) { 13426 BBR_STAT_INC(bbr_failed_mbuf_aloc); 13427 bbr_log_enobuf_jmp(bbr, len, cts, __LINE__, len, 0, 0); 13428 SOCKBUF_UNLOCK(sb); 13429 error = ENOBUFS; 13430 sack_rxmit = 0; 13431 goto out; 13432 } 13433 m->m_data += max_linkhdr; 13434 m->m_len = hdrlen; 13435 /* 13436 * Start the m_copy functions from the closest mbuf to the 13437 * sb_offset in the socket buffer chain. 13438 */ 13439 if ((sb_offset > sbavail(sb)) || ((len + sb_offset) > sbavail(sb))) { 13440 #ifdef BBR_INVARIANTS 13441 if ((len + sb_offset) > (sbavail(sb) + ((flags & (TH_FIN | TH_SYN)) ? 1 : 0))) 13442 panic("tp:%p bbr:%p len:%u sb_offset:%u sbavail:%u rsm:%p %u:%u:%u", 13443 tp, bbr, len, sb_offset, sbavail(sb), rsm, 13444 doing_retran_from, 13445 picked_up_retran, 13446 doing_tlp); 13447 13448 #endif 13449 /* 13450 * In this messed up situation we have two choices, 13451 * a) pretend the send worked, and just start timers 13452 * and what not (not good since that may lead us 13453 * back here a lot). <or> b) Send the lowest segment 13454 * in the map. <or> c) Drop the connection. Lets do 13455 * <b> which if it continues to happen will lead to 13456 * <c> via timeouts. 13457 */ 13458 BBR_STAT_INC(bbr_offset_recovery); 13459 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map); 13460 sb_offset = 0; 13461 if (rsm == NULL) { 13462 sack_rxmit = 0; 13463 len = sbavail(sb); 13464 } else { 13465 sack_rxmit = 1; 13466 if (rsm->r_start != tp->snd_una) { 13467 /* 13468 * Things are really messed up, <c> 13469 * is the only thing to do. 13470 */ 13471 BBR_STAT_INC(bbr_offset_drop); 13472 tcp_set_inp_to_drop(inp, EFAULT); 13473 return (0); 13474 } 13475 len = rsm->r_end - rsm->r_start; 13476 } 13477 if (len > sbavail(sb)) 13478 len = sbavail(sb); 13479 if (len > maxseg) 13480 len = maxseg; 13481 } 13482 mb = sbsndptr_noadv(sb, sb_offset, &moff); 13483 if (len <= MHLEN - hdrlen - max_linkhdr && !hw_tls) { 13484 m_copydata(mb, moff, (int)len, 13485 mtod(m, caddr_t)+hdrlen); 13486 if (rsm == NULL) 13487 sbsndptr_adv(sb, mb, len); 13488 m->m_len += len; 13489 } else { 13490 struct sockbuf *msb; 13491 13492 if (rsm) 13493 msb = NULL; 13494 else 13495 msb = sb; 13496 #ifdef BBR_INVARIANTS 13497 if ((len + moff) > (sbavail(sb) + ((flags & (TH_FIN | TH_SYN)) ? 1 : 0))) { 13498 if (rsm) { 13499 panic("tp:%p bbr:%p len:%u moff:%u sbavail:%u rsm:%p snd_una:%u rsm_start:%u flg:%x %u:%u:%u sr:%d ", 13500 tp, bbr, len, moff, 13501 sbavail(sb), rsm, 13502 tp->snd_una, rsm->r_flags, rsm->r_start, 13503 doing_retran_from, 13504 picked_up_retran, 13505 doing_tlp, sack_rxmit); 13506 } else { 13507 panic("tp:%p bbr:%p len:%u moff:%u sbavail:%u sb_offset:%u snd_una:%u", 13508 tp, bbr, len, moff, sbavail(sb), sb_offset, tp->snd_una); 13509 } 13510 } 13511 #endif 13512 orig_len = len; 13513 m->m_next = tcp_m_copym( 13514 #ifdef NETFLIX_COPY_ARGS 13515 tp, 13516 #endif 13517 mb, moff, &len, 13518 if_hw_tsomaxsegcount, 13519 if_hw_tsomaxsegsize, msb, 13520 ((rsm == NULL) ? hw_tls : 0) 13521 #ifdef NETFLIX_COPY_ARGS 13522 , &filled_all 13523 #endif 13524 ); 13525 if (len <= maxseg && !force_tso) { 13526 /* 13527 * Must have ran out of mbufs for the copy 13528 * shorten it to no longer need tso. Lets 13529 * not put on sendalot since we are low on 13530 * mbufs. 13531 */ 13532 tso = 0; 13533 } 13534 if (m->m_next == NULL) { 13535 SOCKBUF_UNLOCK(sb); 13536 (void)m_free(m); 13537 error = ENOBUFS; 13538 sack_rxmit = 0; 13539 goto out; 13540 } 13541 } 13542 #ifdef BBR_INVARIANTS 13543 if (tso && len < maxseg) { 13544 panic("tp:%p tso on, but len:%d < maxseg:%d", 13545 tp, len, maxseg); 13546 } 13547 if (tso && if_hw_tsomaxsegcount) { 13548 int32_t seg_cnt = 0; 13549 struct mbuf *foo; 13550 13551 foo = m; 13552 while (foo) { 13553 seg_cnt++; 13554 foo = foo->m_next; 13555 } 13556 if (seg_cnt > if_hw_tsomaxsegcount) { 13557 panic("seg_cnt:%d > max:%d", seg_cnt, if_hw_tsomaxsegcount); 13558 } 13559 } 13560 #endif 13561 /* 13562 * If we're sending everything we've got, set PUSH. (This 13563 * will keep happy those implementations which only give 13564 * data to the user when a buffer fills or a PUSH comes in.) 13565 */ 13566 if (sb_offset + len == sbused(sb) && 13567 sbused(sb) && 13568 !(flags & TH_SYN)) { 13569 flags |= TH_PUSH; 13570 } 13571 SOCKBUF_UNLOCK(sb); 13572 } else { 13573 SOCKBUF_UNLOCK(sb); 13574 if (tp->t_flags & TF_ACKNOW) 13575 TCPSTAT_INC(tcps_sndacks); 13576 else if (flags & (TH_SYN | TH_FIN | TH_RST)) 13577 TCPSTAT_INC(tcps_sndctrl); 13578 else if (SEQ_GT(tp->snd_up, tp->snd_una)) 13579 TCPSTAT_INC(tcps_sndurg); 13580 else 13581 TCPSTAT_INC(tcps_sndwinup); 13582 13583 m = m_gethdr(M_NOWAIT, MT_DATA); 13584 if (m == NULL) { 13585 BBR_STAT_INC(bbr_failed_mbuf_aloc); 13586 bbr_log_enobuf_jmp(bbr, len, cts, __LINE__, len, 0, 0); 13587 error = ENOBUFS; 13588 /* Fudge the send time since we could not send */ 13589 sack_rxmit = 0; 13590 goto out; 13591 } 13592 #ifdef INET6 13593 if (isipv6 && (MHLEN < hdrlen + max_linkhdr) && 13594 MHLEN >= hdrlen) { 13595 M_ALIGN(m, hdrlen); 13596 } else 13597 #endif 13598 m->m_data += max_linkhdr; 13599 m->m_len = hdrlen; 13600 } 13601 SOCKBUF_UNLOCK_ASSERT(sb); 13602 m->m_pkthdr.rcvif = (struct ifnet *)0; 13603 #ifdef MAC 13604 mac_inpcb_create_mbuf(inp, m); 13605 #endif 13606 #ifdef INET6 13607 if (isipv6) { 13608 ip6 = mtod(m, struct ip6_hdr *); 13609 #ifdef NETFLIX_TCPOUDP 13610 if (tp->t_port) { 13611 udp = (struct udphdr *)((caddr_t)ip6 + ipoptlen + sizeof(struct ip6_hdr)); 13612 udp->uh_sport = htons(V_tcp_udp_tunneling_port); 13613 udp->uh_dport = tp->t_port; 13614 ulen = hdrlen + len - sizeof(struct ip6_hdr); 13615 udp->uh_ulen = htons(ulen); 13616 th = (struct tcphdr *)(udp + 1); 13617 } else { 13618 #endif 13619 th = (struct tcphdr *)(ip6 + 1); 13620 13621 #ifdef NETFLIX_TCPOUDP 13622 } 13623 #endif 13624 tcpip_fillheaders(inp, 13625 #ifdef NETFLIX_TCPOUDP 13626 tp->t_port, 13627 #endif 13628 ip6, th); 13629 } else 13630 #endif /* INET6 */ 13631 { 13632 ip = mtod(m, struct ip *); 13633 #ifdef TCPDEBUG 13634 ipov = (struct ipovly *)ip; 13635 #endif 13636 #ifdef NETFLIX_TCPOUDP 13637 if (tp->t_port) { 13638 udp = (struct udphdr *)((caddr_t)ip + ipoptlen + sizeof(struct ip)); 13639 udp->uh_sport = htons(V_tcp_udp_tunneling_port); 13640 udp->uh_dport = tp->t_port; 13641 ulen = hdrlen + len - sizeof(struct ip); 13642 udp->uh_ulen = htons(ulen); 13643 th = (struct tcphdr *)(udp + 1); 13644 } else 13645 #endif 13646 th = (struct tcphdr *)(ip + 1); 13647 tcpip_fillheaders(inp, 13648 #ifdef NETFLIX_TCPOUDP 13649 tp->t_port, 13650 #endif 13651 ip, th); 13652 } 13653 /* 13654 * If we are doing retransmissions, then snd_nxt will not reflect 13655 * the first unsent octet. For ACK only packets, we do not want the 13656 * sequence number of the retransmitted packet, we want the sequence 13657 * number of the next unsent octet. So, if there is no data (and no 13658 * SYN or FIN), use snd_max instead of snd_nxt when filling in 13659 * ti_seq. But if we are in persist state, snd_max might reflect 13660 * one byte beyond the right edge of the window, so use snd_nxt in 13661 * that case, since we know we aren't doing a retransmission. 13662 * (retransmit and persist are mutually exclusive...) 13663 */ 13664 if (sack_rxmit == 0) { 13665 if (len && ((flags & (TH_FIN | TH_SYN | TH_RST)) == 0)) { 13666 /* New data (including new persists) */ 13667 th->th_seq = htonl(tp->snd_max); 13668 bbr_seq = tp->snd_max; 13669 } else if (flags & TH_SYN) { 13670 /* Syn's always send from iss */ 13671 th->th_seq = htonl(tp->iss); 13672 bbr_seq = tp->iss; 13673 } else if (flags & TH_FIN) { 13674 if (flags & TH_FIN && tp->t_flags & TF_SENTFIN) { 13675 /* 13676 * If we sent the fin already its 1 minus 13677 * snd_max 13678 */ 13679 th->th_seq = (htonl(tp->snd_max - 1)); 13680 bbr_seq = (tp->snd_max - 1); 13681 } else { 13682 /* First time FIN use snd_max */ 13683 th->th_seq = htonl(tp->snd_max); 13684 bbr_seq = tp->snd_max; 13685 } 13686 } else if (flags & TH_RST) { 13687 /* 13688 * For a Reset send the last cum ack in sequence 13689 * (this like any other choice may still generate a 13690 * challenge ack, if a ack-update packet is in 13691 * flight). 13692 */ 13693 th->th_seq = htonl(tp->snd_una); 13694 bbr_seq = tp->snd_una; 13695 } else { 13696 /* 13697 * len == 0 and not persist we use snd_max, sending 13698 * an ack unless we have sent the fin then its 1 13699 * minus. 13700 */ 13701 /* 13702 * XXXRRS Question if we are in persists and we have 13703 * nothing outstanding to send and we have not sent 13704 * a FIN, we will send an ACK. In such a case it 13705 * might be better to send (tp->snd_una - 1) which 13706 * would force the peer to ack. 13707 */ 13708 if (tp->t_flags & TF_SENTFIN) { 13709 th->th_seq = htonl(tp->snd_max - 1); 13710 bbr_seq = (tp->snd_max - 1); 13711 } else { 13712 th->th_seq = htonl(tp->snd_max); 13713 bbr_seq = tp->snd_max; 13714 } 13715 } 13716 } else { 13717 /* All retransmits use the rsm to guide the send */ 13718 th->th_seq = htonl(rsm->r_start); 13719 bbr_seq = rsm->r_start; 13720 } 13721 th->th_ack = htonl(tp->rcv_nxt); 13722 if (optlen) { 13723 bcopy(opt, th + 1, optlen); 13724 th->th_off = (sizeof(struct tcphdr) + optlen) >> 2; 13725 } 13726 th->th_flags = flags; 13727 /* 13728 * Calculate receive window. Don't shrink window, but avoid silly 13729 * window syndrome. 13730 */ 13731 if ((flags & TH_RST) || ((recwin < (so->so_rcv.sb_hiwat / 4) && 13732 recwin < maxseg))) 13733 recwin = 0; 13734 if (SEQ_GT(tp->rcv_adv, tp->rcv_nxt) && 13735 recwin < (tp->rcv_adv - tp->rcv_nxt)) 13736 recwin = (tp->rcv_adv - tp->rcv_nxt); 13737 if (recwin > TCP_MAXWIN << tp->rcv_scale) 13738 recwin = TCP_MAXWIN << tp->rcv_scale; 13739 13740 /* 13741 * According to RFC1323 the window field in a SYN (i.e., a <SYN> or 13742 * <SYN,ACK>) segment itself is never scaled. The <SYN,ACK> case is 13743 * handled in syncache. 13744 */ 13745 if (flags & TH_SYN) 13746 th->th_win = htons((u_short) 13747 (min(sbspace(&so->so_rcv), TCP_MAXWIN))); 13748 else 13749 th->th_win = htons((u_short)(recwin >> tp->rcv_scale)); 13750 /* 13751 * Adjust the RXWIN0SENT flag - indicate that we have advertised a 0 13752 * window. This may cause the remote transmitter to stall. This 13753 * flag tells soreceive() to disable delayed acknowledgements when 13754 * draining the buffer. This can occur if the receiver is 13755 * attempting to read more data than can be buffered prior to 13756 * transmitting on the connection. 13757 */ 13758 if (th->th_win == 0) { 13759 tp->t_sndzerowin++; 13760 tp->t_flags |= TF_RXWIN0SENT; 13761 } else 13762 tp->t_flags &= ~TF_RXWIN0SENT; 13763 if (SEQ_GT(tp->snd_up, tp->snd_max)) { 13764 th->th_urp = htons((u_short)(tp->snd_up - tp->snd_max)); 13765 th->th_flags |= TH_URG; 13766 } else 13767 /* 13768 * If no urgent pointer to send, then we pull the urgent 13769 * pointer to the left edge of the send window so that it 13770 * doesn't drift into the send window on sequence number 13771 * wraparound. 13772 */ 13773 tp->snd_up = tp->snd_una; /* drag it along */ 13774 13775 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 13776 if (to.to_flags & TOF_SIGNATURE) { 13777 /* 13778 * Calculate MD5 signature and put it into the place 13779 * determined before. NOTE: since TCP options buffer doesn't 13780 * point into mbuf's data, calculate offset and use it. 13781 */ 13782 if (!TCPMD5_ENABLED() || TCPMD5_OUTPUT(m, th, 13783 (u_char *)(th + 1) + (to.to_signature - opt)) != 0) { 13784 /* 13785 * Do not send segment if the calculation of MD5 13786 * digest has failed. 13787 */ 13788 goto out; 13789 } 13790 } 13791 #endif 13792 13793 /* 13794 * Put TCP length in extended header, and then checksum extended 13795 * header and data. 13796 */ 13797 m->m_pkthdr.len = hdrlen + len; /* in6_cksum() need this */ 13798 #ifdef INET6 13799 if (isipv6) { 13800 /* 13801 * ip6_plen is not need to be filled now, and will be filled 13802 * in ip6_output. 13803 */ 13804 #ifdef NETFLIX_TCPOUDP 13805 if (tp->t_port) { 13806 m->m_pkthdr.csum_flags = CSUM_UDP_IPV6; 13807 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 13808 udp->uh_sum = in6_cksum_pseudo(ip6, ulen, IPPROTO_UDP, 0); 13809 th->th_sum = htons(0); 13810 UDPSTAT_INC(udps_opackets); 13811 } else { 13812 #endif 13813 csum_flags = m->m_pkthdr.csum_flags = CSUM_TCP_IPV6; 13814 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 13815 th->th_sum = in6_cksum_pseudo(ip6, sizeof(struct tcphdr) + 13816 optlen + len, IPPROTO_TCP, 0); 13817 #ifdef NETFLIX_TCPOUDP 13818 } 13819 #endif 13820 } 13821 #endif 13822 #if defined(INET6) && defined(INET) 13823 else 13824 #endif 13825 #ifdef INET 13826 { 13827 #ifdef NETFLIX_TCPOUDP 13828 if (tp->t_port) { 13829 m->m_pkthdr.csum_flags = CSUM_UDP; 13830 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 13831 udp->uh_sum = in_pseudo(ip->ip_src.s_addr, 13832 ip->ip_dst.s_addr, htons(ulen + IPPROTO_UDP)); 13833 th->th_sum = htons(0); 13834 UDPSTAT_INC(udps_opackets); 13835 } else { 13836 #endif 13837 csum_flags = m->m_pkthdr.csum_flags = CSUM_TCP; 13838 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 13839 th->th_sum = in_pseudo(ip->ip_src.s_addr, 13840 ip->ip_dst.s_addr, htons(sizeof(struct tcphdr) + 13841 IPPROTO_TCP + len + optlen)); 13842 #ifdef NETFLIX_TCPOUDP 13843 } 13844 #endif 13845 /* IP version must be set here for ipv4/ipv6 checking later */ 13846 KASSERT(ip->ip_v == IPVERSION, 13847 ("%s: IP version incorrect: %d", __func__, ip->ip_v)); 13848 } 13849 #endif 13850 13851 /* 13852 * Enable TSO and specify the size of the segments. The TCP pseudo 13853 * header checksum is always provided. XXX: Fixme: This is currently 13854 * not the case for IPv6. 13855 */ 13856 if (tso || force_tso) { 13857 KASSERT(force_tso || len > maxseg, 13858 ("%s: len:%d <= tso_segsz:%d", __func__, len, maxseg)); 13859 m->m_pkthdr.csum_flags |= CSUM_TSO; 13860 csum_flags |= CSUM_TSO; 13861 m->m_pkthdr.tso_segsz = maxseg; 13862 } 13863 KASSERT(len + hdrlen == m_length(m, NULL), 13864 ("%s: mbuf chain different than expected: %d + %u != %u", 13865 __func__, len, hdrlen, m_length(m, NULL))); 13866 13867 #ifdef TCP_HHOOK 13868 /* Run HHOOK_TC_ESTABLISHED_OUT helper hooks. */ 13869 hhook_run_tcp_est_out(tp, th, &to, len, tso); 13870 #endif 13871 #ifdef TCPDEBUG 13872 /* 13873 * Trace. 13874 */ 13875 if (so->so_options & SO_DEBUG) { 13876 u_short save = 0; 13877 13878 #ifdef INET6 13879 if (!isipv6) 13880 #endif 13881 { 13882 save = ipov->ih_len; 13883 ipov->ih_len = htons(m->m_pkthdr.len /* - hdrlen + 13884 * (th->th_off << 2) */ ); 13885 } 13886 tcp_trace(TA_OUTPUT, tp->t_state, tp, mtod(m, void *), th, 0); 13887 #ifdef INET6 13888 if (!isipv6) 13889 #endif 13890 ipov->ih_len = save; 13891 } 13892 #endif /* TCPDEBUG */ 13893 13894 /* Log to the black box */ 13895 if (tp->t_logstate != TCP_LOG_STATE_OFF) { 13896 union tcp_log_stackspecific log; 13897 13898 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 13899 /* Record info on type of transmission */ 13900 log.u_bbr.flex1 = bbr->r_ctl.rc_hptsi_agg_delay; 13901 log.u_bbr.flex2 = (bbr->r_recovery_bw << 3); 13902 log.u_bbr.flex3 = maxseg; 13903 log.u_bbr.flex4 = delay_calc; 13904 /* Encode filled_all into the upper flex5 bit */ 13905 log.u_bbr.flex5 = bbr->rc_past_init_win; 13906 log.u_bbr.flex5 <<= 1; 13907 log.u_bbr.flex5 |= bbr->rc_no_pacing; 13908 log.u_bbr.flex5 <<= 29; 13909 if (filled_all) 13910 log.u_bbr.flex5 |= 0x80000000; 13911 log.u_bbr.flex5 |= tp->t_maxseg; 13912 log.u_bbr.flex6 = bbr->r_ctl.rc_pace_max_segs; 13913 log.u_bbr.flex7 = (bbr->rc_bbr_state << 8) | bbr_state_val(bbr); 13914 /* lets poke in the low and the high here for debugging */ 13915 log.u_bbr.pkts_out = bbr->rc_tp->t_maxseg; 13916 if (rsm || sack_rxmit) { 13917 if (doing_tlp) 13918 log.u_bbr.flex8 = 2; 13919 else 13920 log.u_bbr.flex8 = 1; 13921 } else { 13922 log.u_bbr.flex8 = 0; 13923 } 13924 lgb = tcp_log_event_(tp, th, &so->so_rcv, &so->so_snd, TCP_LOG_OUT, ERRNO_UNK, 13925 len, &log, false, NULL, NULL, 0, tv); 13926 } else { 13927 lgb = NULL; 13928 } 13929 /* 13930 * Fill in IP length and desired time to live and send to IP level. 13931 * There should be a better way to handle ttl and tos; we could keep 13932 * them in the template, but need a way to checksum without them. 13933 */ 13934 /* 13935 * m->m_pkthdr.len should have been set before cksum calcuration, 13936 * because in6_cksum() need it. 13937 */ 13938 #ifdef INET6 13939 if (isipv6) { 13940 /* 13941 * we separately set hoplimit for every segment, since the 13942 * user might want to change the value via setsockopt. Also, 13943 * desired default hop limit might be changed via Neighbor 13944 * Discovery. 13945 */ 13946 ip6->ip6_hlim = in6_selecthlim(inp, NULL); 13947 13948 /* 13949 * Set the packet size here for the benefit of DTrace 13950 * probes. ip6_output() will set it properly; it's supposed 13951 * to include the option header lengths as well. 13952 */ 13953 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(*ip6)); 13954 13955 if (V_path_mtu_discovery && maxseg > V_tcp_minmss) 13956 tp->t_flags2 |= TF2_PLPMTU_PMTUD; 13957 else 13958 tp->t_flags2 &= ~TF2_PLPMTU_PMTUD; 13959 13960 if (tp->t_state == TCPS_SYN_SENT) 13961 TCP_PROBE5(connect__request, NULL, tp, ip6, tp, th); 13962 13963 TCP_PROBE5(send, NULL, tp, ip6, tp, th); 13964 /* TODO: IPv6 IP6TOS_ECT bit on */ 13965 error = ip6_output(m, inp->in6p_outputopts, 13966 &inp->inp_route6, 13967 ((rsm || sack_rxmit) ? IP_NO_SND_TAG_RL : 0), 13968 NULL, NULL, inp); 13969 13970 if (error == EMSGSIZE && inp->inp_route6.ro_rt != NULL) 13971 mtu = inp->inp_route6.ro_rt->rt_mtu; 13972 } 13973 #endif /* INET6 */ 13974 #if defined(INET) && defined(INET6) 13975 else 13976 #endif 13977 #ifdef INET 13978 { 13979 ip->ip_len = htons(m->m_pkthdr.len); 13980 #ifdef INET6 13981 if (isipv6) 13982 ip->ip_ttl = in6_selecthlim(inp, NULL); 13983 #endif /* INET6 */ 13984 /* 13985 * If we do path MTU discovery, then we set DF on every 13986 * packet. This might not be the best thing to do according 13987 * to RFC3390 Section 2. However the tcp hostcache migitates 13988 * the problem so it affects only the first tcp connection 13989 * with a host. 13990 * 13991 * NB: Don't set DF on small MTU/MSS to have a safe 13992 * fallback. 13993 */ 13994 if (V_path_mtu_discovery && tp->t_maxseg > V_tcp_minmss) { 13995 tp->t_flags2 |= TF2_PLPMTU_PMTUD; 13996 if (tp->t_port == 0 || len < V_tcp_minmss) { 13997 ip->ip_off |= htons(IP_DF); 13998 } 13999 } else { 14000 tp->t_flags2 &= ~TF2_PLPMTU_PMTUD; 14001 } 14002 14003 if (tp->t_state == TCPS_SYN_SENT) 14004 TCP_PROBE5(connect__request, NULL, tp, ip, tp, th); 14005 14006 TCP_PROBE5(send, NULL, tp, ip, tp, th); 14007 14008 error = ip_output(m, inp->inp_options, &inp->inp_route, 14009 ((rsm || sack_rxmit) ? IP_NO_SND_TAG_RL : 0), 0, 14010 inp); 14011 if (error == EMSGSIZE && inp->inp_route.ro_rt != NULL) 14012 mtu = inp->inp_route.ro_rt->rt_mtu; 14013 } 14014 #endif /* INET */ 14015 out: 14016 14017 if (lgb) { 14018 lgb->tlb_errno = error; 14019 lgb = NULL; 14020 } 14021 /* 14022 * In transmit state, time the transmission and arrange for the 14023 * retransmit. In persist state, just set snd_max. 14024 */ 14025 if (error == 0) { 14026 if (TCPS_HAVEESTABLISHED(tp->t_state) && 14027 (tp->t_flags & TF_SACK_PERMIT) && 14028 tp->rcv_numsacks > 0) 14029 tcp_clean_dsack_blocks(tp); 14030 /* We sent an ack clear the bbr_segs_rcvd count */ 14031 bbr->output_error_seen = 0; 14032 bbr->oerror_cnt = 0; 14033 bbr->bbr_segs_rcvd = 0; 14034 if (len == 0) 14035 counter_u64_add(bbr_out_size[TCP_MSS_ACCT_SNDACK], 1); 14036 else if (hw_tls) { 14037 if (filled_all || 14038 (len >= bbr->r_ctl.rc_pace_max_segs)) 14039 BBR_STAT_INC(bbr_meets_tso_thresh); 14040 else { 14041 if (doing_tlp) { 14042 BBR_STAT_INC(bbr_miss_tlp); 14043 bbr_log_type_hrdwtso(tp, bbr, len, 1, what_we_can); 14044 14045 14046 } else if (rsm) { 14047 BBR_STAT_INC(bbr_miss_retran); 14048 bbr_log_type_hrdwtso(tp, bbr, len, 2, what_we_can); 14049 } else if ((ctf_outstanding(tp) + bbr->r_ctl.rc_pace_max_segs) > sbavail(sb)) { 14050 BBR_STAT_INC(bbr_miss_tso_app); 14051 bbr_log_type_hrdwtso(tp, bbr, len, 3, what_we_can); 14052 } else if ((ctf_flight_size(tp, (bbr->r_ctl.rc_sacked + 14053 bbr->r_ctl.rc_lost_bytes)) + bbr->r_ctl.rc_pace_max_segs) > tp->snd_cwnd) { 14054 BBR_STAT_INC(bbr_miss_tso_cwnd); 14055 bbr_log_type_hrdwtso(tp, bbr, len, 4, what_we_can); 14056 } else if ((ctf_outstanding(tp) + bbr->r_ctl.rc_pace_max_segs) > tp->snd_wnd) { 14057 BBR_STAT_INC(bbr_miss_tso_rwnd); 14058 bbr_log_type_hrdwtso(tp, bbr, len, 5, what_we_can); 14059 } else { 14060 BBR_STAT_INC(bbr_miss_unknown); 14061 bbr_log_type_hrdwtso(tp, bbr, len, 6, what_we_can); 14062 } 14063 } 14064 } 14065 /* Do accounting for new sends */ 14066 if ((len > 0) && (rsm == NULL)) { 14067 int idx; 14068 if (tp->snd_una == tp->snd_max) { 14069 /* 14070 * Special case to match google, when 14071 * nothing is in flight the delivered 14072 * time does get updated to the current 14073 * time (see tcp_rate_bsd.c). 14074 */ 14075 bbr->r_ctl.rc_del_time = cts; 14076 } 14077 if (len >= maxseg) { 14078 idx = (len / maxseg) + 3; 14079 if (idx >= TCP_MSS_ACCT_ATIMER) 14080 counter_u64_add(bbr_out_size[(TCP_MSS_ACCT_ATIMER - 1)], 1); 14081 else 14082 counter_u64_add(bbr_out_size[idx], 1); 14083 } else { 14084 /* smaller than a MSS */ 14085 idx = len / (bbr_hptsi_bytes_min - bbr->rc_last_options); 14086 if (idx >= TCP_MSS_SMALL_MAX_SIZE_DIV) 14087 idx = (TCP_MSS_SMALL_MAX_SIZE_DIV - 1); 14088 counter_u64_add(bbr_out_size[(idx + TCP_MSS_SMALL_SIZE_OFF)], 1); 14089 } 14090 } 14091 } 14092 abandon = 0; 14093 /* 14094 * We must do the send accounting before we log the output, 14095 * otherwise the state of the rsm could change and we account to the 14096 * wrong bucket. 14097 */ 14098 if (len > 0) { 14099 bbr_do_send_accounting(tp, bbr, rsm, len, error); 14100 if (error == 0) { 14101 if (tp->snd_una == tp->snd_max) 14102 bbr->r_ctl.rc_tlp_rxt_last_time = cts; 14103 } 14104 } 14105 bbr_log_output(bbr, tp, &to, len, bbr_seq, (uint8_t) flags, error, 14106 cts, mb, &abandon, rsm, 0, sb); 14107 if (abandon) { 14108 /* 14109 * If bbr_log_output destroys the TCB or sees a TH_RST being 14110 * sent we should hit this condition. 14111 */ 14112 return (0); 14113 } 14114 if (((tp->t_flags & TF_FORCEDATA) == 0) || 14115 (bbr->rc_in_persist == 0)) { 14116 /* 14117 * Advance snd_nxt over sequence space of this segment. 14118 */ 14119 if (error) 14120 /* We don't log or do anything with errors */ 14121 goto skip_upd; 14122 14123 if (tp->snd_una == tp->snd_max && 14124 (len || (flags & (TH_SYN | TH_FIN)))) { 14125 /* 14126 * Update the time we just added data since none was 14127 * outstanding. 14128 */ 14129 bbr_log_progress_event(bbr, tp, ticks, PROGRESS_START, __LINE__); 14130 bbr->rc_tp->t_acktime = ticks; 14131 } 14132 if (flags & (TH_SYN | TH_FIN) && (rsm == NULL)) { 14133 if (flags & TH_SYN) { 14134 tp->snd_max++; 14135 } 14136 if ((flags & TH_FIN) && ((tp->t_flags & TF_SENTFIN) == 0)) { 14137 tp->snd_max++; 14138 tp->t_flags |= TF_SENTFIN; 14139 } 14140 } 14141 if (sack_rxmit == 0) 14142 tp->snd_max += len; 14143 skip_upd: 14144 if ((error == 0) && len) 14145 tot_len += len; 14146 } else { 14147 /* Persists case */ 14148 int32_t xlen = len; 14149 14150 if (error) 14151 goto nomore; 14152 14153 if (flags & TH_SYN) 14154 ++xlen; 14155 if ((flags & TH_FIN) && ((tp->t_flags & TF_SENTFIN) == 0)) { 14156 ++xlen; 14157 tp->t_flags |= TF_SENTFIN; 14158 } 14159 if (xlen && (tp->snd_una == tp->snd_max)) { 14160 /* 14161 * Update the time we just added data since none was 14162 * outstanding. 14163 */ 14164 bbr_log_progress_event(bbr, tp, ticks, PROGRESS_START, __LINE__); 14165 bbr->rc_tp->t_acktime = ticks; 14166 } 14167 if (sack_rxmit == 0) 14168 tp->snd_max += xlen; 14169 tot_len += (len + optlen + ipoptlen); 14170 } 14171 nomore: 14172 if (error) { 14173 /* 14174 * Failures do not advance the seq counter above. For the 14175 * case of ENOBUFS we will fall out and become ack-clocked. 14176 * capping the cwnd at the current flight. 14177 * Everything else will just have to retransmit with the timer 14178 * (no pacer). 14179 */ 14180 SOCKBUF_UNLOCK_ASSERT(sb); 14181 BBR_STAT_INC(bbr_saw_oerr); 14182 /* Clear all delay/early tracks */ 14183 bbr->r_ctl.rc_hptsi_agg_delay = 0; 14184 bbr->r_ctl.rc_agg_early = 0; 14185 bbr->r_agg_early_set = 0; 14186 bbr->output_error_seen = 1; 14187 if (bbr->oerror_cnt < 0xf) 14188 bbr->oerror_cnt++; 14189 if (bbr_max_net_error_cnt && (bbr->oerror_cnt >= bbr_max_net_error_cnt)) { 14190 /* drop the session */ 14191 tcp_set_inp_to_drop(inp, ENETDOWN); 14192 } 14193 switch (error) { 14194 case ENOBUFS: 14195 /* 14196 * Make this guy have to get ack's to send 14197 * more but lets make sure we don't 14198 * slam him below a T-O (1MSS). 14199 */ 14200 if (bbr->rc_bbr_state != BBR_STATE_PROBE_RTT) { 14201 tp->snd_cwnd = ctf_flight_size(tp, (bbr->r_ctl.rc_sacked + 14202 bbr->r_ctl.rc_lost_bytes)) - maxseg; 14203 if (tp->snd_cwnd < maxseg) 14204 tp->snd_cwnd = maxseg; 14205 } 14206 slot = (bbr_error_base_paceout + 1) << bbr->oerror_cnt; 14207 BBR_STAT_INC(bbr_saw_enobuf); 14208 if (bbr->bbr_hdrw_pacing) 14209 counter_u64_add(bbr_hdwr_pacing_enobuf, 1); 14210 else 14211 counter_u64_add(bbr_nohdwr_pacing_enobuf, 1); 14212 /* 14213 * Here even in the enobuf's case we want to do our 14214 * state update. The reason being we may have been 14215 * called by the input function. If so we have had 14216 * things change. 14217 */ 14218 error = 0; 14219 goto enobufs; 14220 case EMSGSIZE: 14221 /* 14222 * For some reason the interface we used initially 14223 * to send segments changed to another or lowered 14224 * its MTU. If TSO was active we either got an 14225 * interface without TSO capabilits or TSO was 14226 * turned off. If we obtained mtu from ip_output() 14227 * then update it and try again. 14228 */ 14229 /* Turn on tracing (or try to) */ 14230 { 14231 int old_maxseg; 14232 14233 old_maxseg = tp->t_maxseg; 14234 BBR_STAT_INC(bbr_saw_emsgsiz); 14235 bbr_log_msgsize_fail(bbr, tp, len, maxseg, mtu, csum_flags, tso, cts); 14236 if (mtu != 0) 14237 tcp_mss_update(tp, -1, mtu, NULL, NULL); 14238 if (old_maxseg <= tp->t_maxseg) { 14239 /* Huh it did not shrink? */ 14240 tp->t_maxseg = old_maxseg - 40; 14241 bbr_log_msgsize_fail(bbr, tp, len, maxseg, mtu, 0, tso, cts); 14242 } 14243 tp->t_flags &= ~TF_FORCEDATA; 14244 /* 14245 * Nuke all other things that can interfere 14246 * with slot 14247 */ 14248 if ((tot_len + len) && (len >= tp->t_maxseg)) { 14249 slot = bbr_get_pacing_delay(bbr, 14250 bbr->r_ctl.rc_bbr_hptsi_gain, 14251 (tot_len + len), cts, 0); 14252 if (slot < bbr_error_base_paceout) 14253 slot = (bbr_error_base_paceout + 2) << bbr->oerror_cnt; 14254 } else 14255 slot = (bbr_error_base_paceout + 2) << bbr->oerror_cnt; 14256 bbr->rc_output_starts_timer = 1; 14257 bbr_start_hpts_timer(bbr, tp, cts, 10, slot, 14258 tot_len); 14259 return (error); 14260 } 14261 case EPERM: 14262 tp->t_softerror = error; 14263 /* Fall through */ 14264 case EHOSTDOWN: 14265 case EHOSTUNREACH: 14266 case ENETDOWN: 14267 case ENETUNREACH: 14268 if (TCPS_HAVERCVDSYN(tp->t_state)) { 14269 tp->t_softerror = error; 14270 } 14271 /* FALLTHROUGH */ 14272 default: 14273 tp->t_flags &= ~TF_FORCEDATA; 14274 slot = (bbr_error_base_paceout + 3) << bbr->oerror_cnt; 14275 bbr->rc_output_starts_timer = 1; 14276 bbr_start_hpts_timer(bbr, tp, cts, 11, slot, 0); 14277 return (error); 14278 } 14279 #ifdef NETFLIX_STATS 14280 } else if (((tp->t_flags & TF_GPUTINPROG) == 0) && 14281 len && 14282 (rsm == NULL) && 14283 (bbr->rc_in_persist == 0)) { 14284 tp->gput_seq = bbr_seq; 14285 tp->gput_ack = bbr_seq + 14286 min(sbavail(&so->so_snd) - sb_offset, sendwin); 14287 tp->gput_ts = cts; 14288 tp->t_flags |= TF_GPUTINPROG; 14289 #endif 14290 } 14291 TCPSTAT_INC(tcps_sndtotal); 14292 if ((bbr->bbr_hdw_pace_ena) && 14293 (bbr->bbr_attempt_hdwr_pace == 0) && 14294 (bbr->rc_past_init_win) && 14295 (bbr->rc_bbr_state != BBR_STATE_STARTUP) && 14296 (get_filter_value(&bbr->r_ctl.rc_delrate)) && 14297 (inp->inp_route.ro_rt && 14298 inp->inp_route.ro_rt->rt_ifp)) { 14299 /* 14300 * We are past the initial window and 14301 * have at least one measurement so we 14302 * could use hardware pacing if its available. 14303 * We have an interface and we have not attempted 14304 * to setup hardware pacing, lets try to now. 14305 */ 14306 uint64_t rate_wanted; 14307 int err = 0; 14308 14309 rate_wanted = bbr_get_hardware_rate(bbr); 14310 bbr->bbr_attempt_hdwr_pace = 1; 14311 bbr->r_ctl.crte = tcp_set_pacing_rate(bbr->rc_tp, 14312 inp->inp_route.ro_rt->rt_ifp, 14313 rate_wanted, 14314 (RS_PACING_GEQ|RS_PACING_SUB_OK), 14315 &err); 14316 if (bbr->r_ctl.crte) { 14317 bbr_type_log_hdwr_pacing(bbr, 14318 bbr->r_ctl.crte->ptbl->rs_ifp, 14319 rate_wanted, 14320 bbr->r_ctl.crte->rate, 14321 __LINE__, cts, err); 14322 BBR_STAT_INC(bbr_hdwr_rl_add_ok); 14323 counter_u64_add(bbr_flows_nohdwr_pacing, -1); 14324 counter_u64_add(bbr_flows_whdwr_pacing, 1); 14325 bbr->bbr_hdrw_pacing = 1; 14326 /* Now what is our gain status? */ 14327 if (bbr->r_ctl.crte->rate < rate_wanted) { 14328 /* We have a problem */ 14329 bbr_setup_less_of_rate(bbr, cts, 14330 bbr->r_ctl.crte->rate, rate_wanted); 14331 } else { 14332 /* We are good */ 14333 bbr->gain_is_limited = 0; 14334 bbr->skip_gain = 0; 14335 } 14336 tcp_bbr_tso_size_check(bbr, cts); 14337 } else { 14338 bbr_type_log_hdwr_pacing(bbr, 14339 inp->inp_route.ro_rt->rt_ifp, 14340 rate_wanted, 14341 0, 14342 __LINE__, cts, err); 14343 BBR_STAT_INC(bbr_hdwr_rl_add_fail); 14344 } 14345 } 14346 if (bbr->bbr_hdrw_pacing) { 14347 /* 14348 * Worry about cases where the route 14349 * changes or something happened that we 14350 * lost our hardware pacing possibly during 14351 * the last ip_output call. 14352 */ 14353 if (inp->inp_snd_tag == NULL) { 14354 /* A change during ip output disabled hw pacing? */ 14355 bbr->bbr_hdrw_pacing = 0; 14356 } else if ((inp->inp_route.ro_rt == NULL) || 14357 (inp->inp_route.ro_rt->rt_ifp != inp->inp_snd_tag->ifp)) { 14358 /* 14359 * We had an interface or route change, 14360 * detach from the current hdwr pacing 14361 * and setup to re-attempt next go 14362 * round. 14363 */ 14364 bbr->bbr_hdrw_pacing = 0; 14365 bbr->bbr_attempt_hdwr_pace = 0; 14366 tcp_rel_pacing_rate(bbr->r_ctl.crte, bbr->rc_tp); 14367 tcp_bbr_tso_size_check(bbr, cts); 14368 } 14369 } 14370 /* 14371 * Data sent (as far as we can tell). If this advertises a larger 14372 * window than any other segment, then remember the size of the 14373 * advertised window. Any pending ACK has now been sent. 14374 */ 14375 if (SEQ_GT(tp->rcv_nxt + recwin, tp->rcv_adv)) 14376 tp->rcv_adv = tp->rcv_nxt + recwin; 14377 14378 tp->last_ack_sent = tp->rcv_nxt; 14379 if ((error == 0) && 14380 (bbr->r_ctl.rc_pace_max_segs > tp->t_maxseg) && 14381 (doing_tlp == 0) && 14382 (tso == 0) && 14383 (hw_tls == 0) && 14384 (len > 0) && 14385 ((flags & TH_RST) == 0) && 14386 (IN_RECOVERY(tp->t_flags) == 0) && 14387 (bbr->rc_in_persist == 0) && 14388 ((tp->t_flags & TF_FORCEDATA) == 0) && 14389 (tot_len < bbr->r_ctl.rc_pace_max_segs)) { 14390 /* 14391 * For non-tso we need to goto again until we have sent out 14392 * enough data to match what we are hptsi out every hptsi 14393 * interval. 14394 */ 14395 if (SEQ_LT(tp->snd_nxt, tp->snd_max)) { 14396 /* Make sure snd_nxt is drug up */ 14397 tp->snd_nxt = tp->snd_max; 14398 } 14399 if (rsm != NULL) { 14400 rsm = NULL; 14401 goto skip_again; 14402 } 14403 rsm = NULL; 14404 sack_rxmit = 0; 14405 tp->t_flags &= ~(TF_ACKNOW | TF_DELACK | TF_FORCEDATA); 14406 goto again; 14407 } 14408 skip_again: 14409 if (((flags & (TH_RST | TH_SYN | TH_FIN)) == 0) && tot_len) { 14410 /* 14411 * Calculate/Re-Calculate the hptsi slot in usecs based on 14412 * what we have sent so far 14413 */ 14414 slot = bbr_get_pacing_delay(bbr, bbr->r_ctl.rc_bbr_hptsi_gain, tot_len, cts, 0); 14415 if (bbr->rc_no_pacing) 14416 slot = 0; 14417 } 14418 tp->t_flags &= ~(TF_ACKNOW | TF_DELACK | TF_FORCEDATA); 14419 enobufs: 14420 if (bbr->rc_use_google == 0) 14421 bbr_check_bbr_for_state(bbr, cts, __LINE__, 0); 14422 bbr_cwnd_limiting(tp, bbr, ctf_flight_size(tp, (bbr->r_ctl.rc_sacked + 14423 bbr->r_ctl.rc_lost_bytes))); 14424 bbr->rc_output_starts_timer = 1; 14425 if (bbr->bbr_use_rack_cheat && 14426 (more_to_rxt || 14427 ((bbr->r_ctl.rc_resend = bbr_check_recovery_mode(tp, bbr, cts)) != NULL))) { 14428 /* Rack cheats and shotguns out all rxt's 1ms apart */ 14429 if (slot > 1000) 14430 slot = 1000; 14431 } 14432 if (bbr->bbr_hdrw_pacing && (bbr->hw_pacing_set == 0)) { 14433 /* 14434 * We don't change the tso size until some number of sends 14435 * to give the hardware commands time to get down 14436 * to the interface. 14437 */ 14438 bbr->r_ctl.bbr_hdwr_cnt_noset_snt++; 14439 if (bbr->r_ctl.bbr_hdwr_cnt_noset_snt >= bbr_hdwr_pacing_delay_cnt) { 14440 bbr->hw_pacing_set = 1; 14441 tcp_bbr_tso_size_check(bbr, cts); 14442 } 14443 } 14444 bbr_start_hpts_timer(bbr, tp, cts, 12, slot, tot_len); 14445 if (SEQ_LT(tp->snd_nxt, tp->snd_max)) { 14446 /* Make sure snd_nxt is drug up */ 14447 tp->snd_nxt = tp->snd_max; 14448 } 14449 return (error); 14450 14451 } 14452 14453 /* 14454 * See bbr_output_wtime() for return values. 14455 */ 14456 static int 14457 bbr_output(struct tcpcb *tp) 14458 { 14459 int32_t ret; 14460 struct timeval tv; 14461 struct tcp_bbr *bbr; 14462 14463 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 14464 INP_WLOCK_ASSERT(tp->t_inpcb); 14465 (void)tcp_get_usecs(&tv); 14466 ret = bbr_output_wtime(tp, &tv); 14467 return (ret); 14468 } 14469 14470 static void 14471 bbr_mtu_chg(struct tcpcb *tp) 14472 { 14473 struct tcp_bbr *bbr; 14474 struct bbr_sendmap *rsm, *frsm = NULL; 14475 uint32_t maxseg; 14476 14477 /* 14478 * The MTU has changed. a) Clear the sack filter. b) Mark everything 14479 * over the current size as SACK_PASS so a retransmit will occur. 14480 */ 14481 14482 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 14483 maxseg = tp->t_maxseg - bbr->rc_last_options; 14484 sack_filter_clear(&bbr->r_ctl.bbr_sf, tp->snd_una); 14485 TAILQ_FOREACH(rsm, &bbr->r_ctl.rc_map, r_next) { 14486 /* Don't mess with ones acked (by sack?) */ 14487 if (rsm->r_flags & BBR_ACKED) 14488 continue; 14489 if ((rsm->r_end - rsm->r_start) > maxseg) { 14490 /* 14491 * We mark sack-passed on all the previous large 14492 * sends we did. This will force them to retransmit. 14493 */ 14494 rsm->r_flags |= BBR_SACK_PASSED; 14495 if (((rsm->r_flags & BBR_MARKED_LOST) == 0) && 14496 bbr_is_lost(bbr, rsm, bbr->r_ctl.rc_rcvtime)) { 14497 bbr->r_ctl.rc_lost_bytes += rsm->r_end - rsm->r_start; 14498 bbr->r_ctl.rc_lost += rsm->r_end - rsm->r_start; 14499 rsm->r_flags |= BBR_MARKED_LOST; 14500 } 14501 if (frsm == NULL) 14502 frsm = rsm; 14503 } 14504 } 14505 if (frsm) { 14506 bbr->r_ctl.rc_resend = frsm; 14507 } 14508 } 14509 14510 /* 14511 * bbr_ctloutput() must drop the inpcb lock before performing copyin on 14512 * socket option arguments. When it re-acquires the lock after the copy, it 14513 * has to revalidate that the connection is still valid for the socket 14514 * option. 14515 */ 14516 static int 14517 bbr_set_sockopt(struct socket *so, struct sockopt *sopt, 14518 struct inpcb *inp, struct tcpcb *tp, struct tcp_bbr *bbr) 14519 { 14520 int32_t error = 0, optval; 14521 14522 switch (sopt->sopt_name) { 14523 case TCP_RACK_PACE_MAX_SEG: 14524 case TCP_RACK_MIN_TO: 14525 case TCP_RACK_REORD_THRESH: 14526 case TCP_RACK_REORD_FADE: 14527 case TCP_RACK_TLP_THRESH: 14528 case TCP_RACK_PKT_DELAY: 14529 case TCP_BBR_ALGORITHM: 14530 case TCP_BBR_TSLIMITS: 14531 case TCP_BBR_IWINTSO: 14532 case TCP_BBR_RECFORCE: 14533 case TCP_BBR_STARTUP_PG: 14534 case TCP_BBR_DRAIN_PG: 14535 case TCP_BBR_RWND_IS_APP: 14536 case TCP_BBR_PROBE_RTT_INT: 14537 case TCP_BBR_PROBE_RTT_GAIN: 14538 case TCP_BBR_PROBE_RTT_LEN: 14539 case TCP_BBR_STARTUP_LOSS_EXIT: 14540 case TCP_BBR_USEDEL_RATE: 14541 case TCP_BBR_MIN_RTO: 14542 case TCP_BBR_MAX_RTO: 14543 case TCP_BBR_PACE_PER_SEC: 14544 case TCP_DELACK: 14545 case TCP_BBR_PACE_DEL_TAR: 14546 case TCP_BBR_SEND_IWND_IN_TSO: 14547 case TCP_BBR_EXTRA_STATE: 14548 case TCP_BBR_UTTER_MAX_TSO: 14549 case TCP_BBR_MIN_TOPACEOUT: 14550 case TCP_BBR_FLOOR_MIN_TSO: 14551 case TCP_BBR_TSTMP_RAISES: 14552 case TCP_BBR_POLICER_DETECT: 14553 case TCP_BBR_USE_RACK_CHEAT: 14554 case TCP_DATA_AFTER_CLOSE: 14555 case TCP_BBR_HDWR_PACE: 14556 case TCP_BBR_PACE_SEG_MAX: 14557 case TCP_BBR_PACE_SEG_MIN: 14558 case TCP_BBR_PACE_CROSS: 14559 case TCP_BBR_PACE_OH: 14560 #ifdef NETFLIX_PEAKRATE 14561 case TCP_MAXPEAKRATE: 14562 #endif 14563 case TCP_BBR_TMR_PACE_OH: 14564 case TCP_BBR_RACK_RTT_USE: 14565 case TCP_BBR_RETRAN_WTSO: 14566 break; 14567 default: 14568 return (tcp_default_ctloutput(so, sopt, inp, tp)); 14569 break; 14570 } 14571 INP_WUNLOCK(inp); 14572 error = sooptcopyin(sopt, &optval, sizeof(optval), sizeof(optval)); 14573 if (error) 14574 return (error); 14575 INP_WLOCK(inp); 14576 if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) { 14577 INP_WUNLOCK(inp); 14578 return (ECONNRESET); 14579 } 14580 tp = intotcpcb(inp); 14581 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 14582 switch (sopt->sopt_name) { 14583 case TCP_BBR_PACE_PER_SEC: 14584 BBR_OPTS_INC(tcp_bbr_pace_per_sec); 14585 bbr->r_ctl.bbr_hptsi_per_second = optval; 14586 break; 14587 case TCP_BBR_PACE_DEL_TAR: 14588 BBR_OPTS_INC(tcp_bbr_pace_del_tar); 14589 bbr->r_ctl.bbr_hptsi_segments_delay_tar = optval; 14590 break; 14591 case TCP_BBR_PACE_SEG_MAX: 14592 BBR_OPTS_INC(tcp_bbr_pace_seg_max); 14593 bbr->r_ctl.bbr_hptsi_segments_max = optval; 14594 break; 14595 case TCP_BBR_PACE_SEG_MIN: 14596 BBR_OPTS_INC(tcp_bbr_pace_seg_min); 14597 bbr->r_ctl.bbr_hptsi_bytes_min = optval; 14598 break; 14599 case TCP_BBR_PACE_CROSS: 14600 BBR_OPTS_INC(tcp_bbr_pace_cross); 14601 bbr->r_ctl.bbr_cross_over = optval; 14602 break; 14603 case TCP_BBR_ALGORITHM: 14604 BBR_OPTS_INC(tcp_bbr_algorithm); 14605 if (optval && (bbr->rc_use_google == 0)) { 14606 /* Turn on the google mode */ 14607 bbr_google_mode_on(bbr); 14608 if ((optval > 3) && (optval < 500)) { 14609 /* 14610 * Must be at least greater than .3% 14611 * and must be less than 50.0%. 14612 */ 14613 bbr->r_ctl.bbr_google_discount = optval; 14614 } 14615 } else if ((optval == 0) && (bbr->rc_use_google == 1)) { 14616 /* Turn off the google mode */ 14617 bbr_google_mode_off(bbr); 14618 } 14619 break; 14620 case TCP_BBR_TSLIMITS: 14621 BBR_OPTS_INC(tcp_bbr_tslimits); 14622 if (optval == 1) 14623 bbr->rc_use_ts_limit = 1; 14624 else if (optval == 0) 14625 bbr->rc_use_ts_limit = 0; 14626 else 14627 error = EINVAL; 14628 break; 14629 14630 case TCP_BBR_IWINTSO: 14631 BBR_OPTS_INC(tcp_bbr_iwintso); 14632 if ((optval >= 0) && (optval < 128)) { 14633 uint32_t twin; 14634 14635 bbr->rc_init_win = optval; 14636 twin = bbr_initial_cwnd(bbr, tp); 14637 if ((bbr->rc_past_init_win == 0) && (twin > tp->snd_cwnd)) 14638 tp->snd_cwnd = twin; 14639 else 14640 error = EBUSY; 14641 } else 14642 error = EINVAL; 14643 break; 14644 case TCP_BBR_STARTUP_PG: 14645 BBR_OPTS_INC(tcp_bbr_startup_pg); 14646 if ((optval > 0) && (optval < BBR_MAX_GAIN_VALUE)) { 14647 bbr->r_ctl.rc_startup_pg = optval; 14648 if (bbr->rc_bbr_state == BBR_STATE_STARTUP) { 14649 bbr->r_ctl.rc_bbr_hptsi_gain = optval; 14650 } 14651 } else 14652 error = EINVAL; 14653 break; 14654 case TCP_BBR_DRAIN_PG: 14655 BBR_OPTS_INC(tcp_bbr_drain_pg); 14656 if ((optval > 0) && (optval < BBR_MAX_GAIN_VALUE)) 14657 bbr->r_ctl.rc_drain_pg = optval; 14658 else 14659 error = EINVAL; 14660 break; 14661 case TCP_BBR_PROBE_RTT_LEN: 14662 BBR_OPTS_INC(tcp_bbr_probertt_len); 14663 if (optval <= 1) 14664 reset_time_small(&bbr->r_ctl.rc_rttprop, (optval * USECS_IN_SECOND)); 14665 else 14666 error = EINVAL; 14667 break; 14668 case TCP_BBR_PROBE_RTT_GAIN: 14669 BBR_OPTS_INC(tcp_bbr_probertt_gain); 14670 if (optval <= BBR_UNIT) 14671 bbr->r_ctl.bbr_rttprobe_gain_val = optval; 14672 else 14673 error = EINVAL; 14674 break; 14675 case TCP_BBR_PROBE_RTT_INT: 14676 BBR_OPTS_INC(tcp_bbr_probe_rtt_int); 14677 if (optval > 1000) 14678 bbr->r_ctl.rc_probertt_int = optval; 14679 else 14680 error = EINVAL; 14681 break; 14682 case TCP_BBR_MIN_TOPACEOUT: 14683 BBR_OPTS_INC(tcp_bbr_topaceout); 14684 if (optval == 0) { 14685 bbr->no_pacing_until = 0; 14686 bbr->rc_no_pacing = 0; 14687 } else if (optval <= 0x00ff) { 14688 bbr->no_pacing_until = optval; 14689 if ((bbr->r_ctl.rc_pkt_epoch < bbr->no_pacing_until) && 14690 (bbr->rc_bbr_state == BBR_STATE_STARTUP)){ 14691 /* Turn on no pacing */ 14692 bbr->rc_no_pacing = 1; 14693 } 14694 } else 14695 error = EINVAL; 14696 break; 14697 case TCP_BBR_STARTUP_LOSS_EXIT: 14698 BBR_OPTS_INC(tcp_bbr_startup_loss_exit); 14699 bbr->rc_loss_exit = optval; 14700 break; 14701 case TCP_BBR_USEDEL_RATE: 14702 error = EINVAL; 14703 break; 14704 case TCP_BBR_MIN_RTO: 14705 BBR_OPTS_INC(tcp_bbr_min_rto); 14706 bbr->r_ctl.rc_min_rto_ms = optval; 14707 break; 14708 case TCP_BBR_MAX_RTO: 14709 BBR_OPTS_INC(tcp_bbr_max_rto); 14710 bbr->rc_max_rto_sec = optval; 14711 break; 14712 case TCP_RACK_MIN_TO: 14713 /* Minimum time between rack t-o's in ms */ 14714 BBR_OPTS_INC(tcp_rack_min_to); 14715 bbr->r_ctl.rc_min_to = optval; 14716 break; 14717 case TCP_RACK_REORD_THRESH: 14718 /* RACK reorder threshold (shift amount) */ 14719 BBR_OPTS_INC(tcp_rack_reord_thresh); 14720 if ((optval > 0) && (optval < 31)) 14721 bbr->r_ctl.rc_reorder_shift = optval; 14722 else 14723 error = EINVAL; 14724 break; 14725 case TCP_RACK_REORD_FADE: 14726 /* Does reordering fade after ms time */ 14727 BBR_OPTS_INC(tcp_rack_reord_fade); 14728 bbr->r_ctl.rc_reorder_fade = optval; 14729 break; 14730 case TCP_RACK_TLP_THRESH: 14731 /* RACK TLP theshold i.e. srtt+(srtt/N) */ 14732 BBR_OPTS_INC(tcp_rack_tlp_thresh); 14733 if (optval) 14734 bbr->rc_tlp_threshold = optval; 14735 else 14736 error = EINVAL; 14737 break; 14738 case TCP_BBR_USE_RACK_CHEAT: 14739 BBR_OPTS_INC(tcp_use_rackcheat); 14740 if (bbr->rc_use_google) { 14741 error = EINVAL; 14742 break; 14743 } 14744 BBR_OPTS_INC(tcp_rack_cheat); 14745 if (optval) 14746 bbr->bbr_use_rack_cheat = 1; 14747 else 14748 bbr->bbr_use_rack_cheat = 0; 14749 break; 14750 case TCP_BBR_FLOOR_MIN_TSO: 14751 BBR_OPTS_INC(tcp_utter_max_tso); 14752 if ((optval >= 0) && (optval < 40)) 14753 bbr->r_ctl.bbr_hptsi_segments_floor = optval; 14754 else 14755 error = EINVAL; 14756 break; 14757 case TCP_BBR_UTTER_MAX_TSO: 14758 BBR_OPTS_INC(tcp_utter_max_tso); 14759 if ((optval >= 0) && (optval < 0xffff)) 14760 bbr->r_ctl.bbr_utter_max = optval; 14761 else 14762 error = EINVAL; 14763 break; 14764 14765 case TCP_BBR_EXTRA_STATE: 14766 BBR_OPTS_INC(tcp_extra_state); 14767 if (optval) 14768 bbr->rc_use_idle_restart = 1; 14769 else 14770 bbr->rc_use_idle_restart = 0; 14771 break; 14772 case TCP_BBR_SEND_IWND_IN_TSO: 14773 BBR_OPTS_INC(tcp_iwnd_tso); 14774 if (optval) { 14775 bbr->bbr_init_win_cheat = 1; 14776 if (bbr->rc_past_init_win == 0) { 14777 uint32_t cts; 14778 cts = tcp_get_usecs(&bbr->rc_tv); 14779 tcp_bbr_tso_size_check(bbr, cts); 14780 } 14781 } else 14782 bbr->bbr_init_win_cheat = 0; 14783 break; 14784 case TCP_BBR_HDWR_PACE: 14785 BBR_OPTS_INC(tcp_hdwr_pacing); 14786 if (optval){ 14787 bbr->bbr_hdw_pace_ena = 1; 14788 bbr->bbr_attempt_hdwr_pace = 0; 14789 } else { 14790 bbr->bbr_hdw_pace_ena = 0; 14791 #ifdef RATELIMIT 14792 if (bbr->bbr_hdrw_pacing) { 14793 bbr->bbr_hdrw_pacing = 0; 14794 in_pcbdetach_txrtlmt(bbr->rc_inp); 14795 } 14796 #endif 14797 } 14798 break; 14799 14800 case TCP_DELACK: 14801 BBR_OPTS_INC(tcp_delack); 14802 if (optval < 100) { 14803 if (optval == 0) /* off */ 14804 tp->t_delayed_ack = 0; 14805 else if (optval == 1) /* on which is 2 */ 14806 tp->t_delayed_ack = 2; 14807 else /* higher than 2 and less than 100 */ 14808 tp->t_delayed_ack = optval; 14809 if (tp->t_flags & TF_DELACK) { 14810 tp->t_flags &= ~TF_DELACK; 14811 tp->t_flags |= TF_ACKNOW; 14812 bbr_output(tp); 14813 } 14814 } else 14815 error = EINVAL; 14816 break; 14817 case TCP_RACK_PKT_DELAY: 14818 /* RACK added ms i.e. rack-rtt + reord + N */ 14819 BBR_OPTS_INC(tcp_rack_pkt_delay); 14820 bbr->r_ctl.rc_pkt_delay = optval; 14821 break; 14822 #ifdef NETFLIX_PEAKRATE 14823 case TCP_MAXPEAKRATE: 14824 BBR_OPTS_INC(tcp_maxpeak); 14825 error = tcp_set_maxpeakrate(tp, optval); 14826 if (!error) 14827 tp->t_peakrate_thr = tp->t_maxpeakrate; 14828 break; 14829 #endif 14830 case TCP_BBR_RETRAN_WTSO: 14831 BBR_OPTS_INC(tcp_retran_wtso); 14832 if (optval) 14833 bbr->rc_resends_use_tso = 1; 14834 else 14835 bbr->rc_resends_use_tso = 0; 14836 break; 14837 case TCP_DATA_AFTER_CLOSE: 14838 BBR_OPTS_INC(tcp_data_ac); 14839 if (optval) 14840 bbr->rc_allow_data_af_clo = 1; 14841 else 14842 bbr->rc_allow_data_af_clo = 0; 14843 break; 14844 case TCP_BBR_POLICER_DETECT: 14845 BBR_OPTS_INC(tcp_policer_det); 14846 if (bbr->rc_use_google == 0) 14847 error = EINVAL; 14848 else if (optval) 14849 bbr->r_use_policer = 1; 14850 else 14851 bbr->r_use_policer = 0; 14852 break; 14853 14854 case TCP_BBR_TSTMP_RAISES: 14855 BBR_OPTS_INC(tcp_ts_raises); 14856 if (optval) 14857 bbr->ts_can_raise = 1; 14858 else 14859 bbr->ts_can_raise = 0; 14860 break; 14861 case TCP_BBR_TMR_PACE_OH: 14862 BBR_OPTS_INC(tcp_pacing_oh_tmr); 14863 if (bbr->rc_use_google) { 14864 error = EINVAL; 14865 } else { 14866 if (optval) 14867 bbr->r_ctl.rc_incr_tmrs = 1; 14868 else 14869 bbr->r_ctl.rc_incr_tmrs = 0; 14870 } 14871 break; 14872 case TCP_BBR_PACE_OH: 14873 BBR_OPTS_INC(tcp_pacing_oh); 14874 if (bbr->rc_use_google) { 14875 error = EINVAL; 14876 } else { 14877 if (optval > (BBR_INCL_TCP_OH| 14878 BBR_INCL_IP_OH| 14879 BBR_INCL_ENET_OH)) { 14880 error = EINVAL; 14881 break; 14882 } 14883 if (optval & BBR_INCL_TCP_OH) 14884 bbr->r_ctl.rc_inc_tcp_oh = 1; 14885 else 14886 bbr->r_ctl.rc_inc_tcp_oh = 0; 14887 if (optval & BBR_INCL_IP_OH) 14888 bbr->r_ctl.rc_inc_ip_oh = 1; 14889 else 14890 bbr->r_ctl.rc_inc_ip_oh = 0; 14891 if (optval & BBR_INCL_ENET_OH) 14892 bbr->r_ctl.rc_inc_enet_oh = 1; 14893 else 14894 bbr->r_ctl.rc_inc_enet_oh = 0; 14895 } 14896 break; 14897 default: 14898 return (tcp_default_ctloutput(so, sopt, inp, tp)); 14899 break; 14900 } 14901 #ifdef NETFLIX_STATS 14902 tcp_log_socket_option(tp, sopt->sopt_name, optval, error); 14903 #endif 14904 INP_WUNLOCK(inp); 14905 return (error); 14906 } 14907 14908 /* 14909 * return 0 on success, error-num on failure 14910 */ 14911 static int 14912 bbr_get_sockopt(struct socket *so, struct sockopt *sopt, 14913 struct inpcb *inp, struct tcpcb *tp, struct tcp_bbr *bbr) 14914 { 14915 int32_t error, optval; 14916 14917 /* 14918 * Because all our options are either boolean or an int, we can just 14919 * pull everything into optval and then unlock and copy. If we ever 14920 * add a option that is not a int, then this will have quite an 14921 * impact to this routine. 14922 */ 14923 switch (sopt->sopt_name) { 14924 case TCP_BBR_PACE_PER_SEC: 14925 optval = bbr->r_ctl.bbr_hptsi_per_second; 14926 break; 14927 case TCP_BBR_PACE_DEL_TAR: 14928 optval = bbr->r_ctl.bbr_hptsi_segments_delay_tar; 14929 break; 14930 case TCP_BBR_PACE_SEG_MAX: 14931 optval = bbr->r_ctl.bbr_hptsi_segments_max; 14932 break; 14933 case TCP_BBR_MIN_TOPACEOUT: 14934 optval = bbr->no_pacing_until; 14935 break; 14936 case TCP_BBR_PACE_SEG_MIN: 14937 optval = bbr->r_ctl.bbr_hptsi_bytes_min; 14938 break; 14939 case TCP_BBR_PACE_CROSS: 14940 optval = bbr->r_ctl.bbr_cross_over; 14941 break; 14942 case TCP_BBR_ALGORITHM: 14943 optval = bbr->rc_use_google; 14944 break; 14945 case TCP_BBR_TSLIMITS: 14946 optval = bbr->rc_use_ts_limit; 14947 break; 14948 case TCP_BBR_IWINTSO: 14949 optval = bbr->rc_init_win; 14950 break; 14951 case TCP_BBR_STARTUP_PG: 14952 optval = bbr->r_ctl.rc_startup_pg; 14953 break; 14954 case TCP_BBR_DRAIN_PG: 14955 optval = bbr->r_ctl.rc_drain_pg; 14956 break; 14957 case TCP_BBR_PROBE_RTT_INT: 14958 optval = bbr->r_ctl.rc_probertt_int; 14959 break; 14960 case TCP_BBR_PROBE_RTT_LEN: 14961 optval = (bbr->r_ctl.rc_rttprop.cur_time_limit / USECS_IN_SECOND); 14962 break; 14963 case TCP_BBR_PROBE_RTT_GAIN: 14964 optval = bbr->r_ctl.bbr_rttprobe_gain_val; 14965 break; 14966 case TCP_BBR_STARTUP_LOSS_EXIT: 14967 optval = bbr->rc_loss_exit; 14968 break; 14969 case TCP_BBR_USEDEL_RATE: 14970 error = EINVAL; 14971 break; 14972 case TCP_BBR_MIN_RTO: 14973 optval = bbr->r_ctl.rc_min_rto_ms; 14974 break; 14975 case TCP_BBR_MAX_RTO: 14976 optval = bbr->rc_max_rto_sec; 14977 break; 14978 case TCP_RACK_PACE_MAX_SEG: 14979 /* Max segments in a pace */ 14980 optval = bbr->r_ctl.rc_pace_max_segs; 14981 break; 14982 case TCP_RACK_MIN_TO: 14983 /* Minimum time between rack t-o's in ms */ 14984 optval = bbr->r_ctl.rc_min_to; 14985 break; 14986 case TCP_RACK_REORD_THRESH: 14987 /* RACK reorder threshold (shift amount) */ 14988 optval = bbr->r_ctl.rc_reorder_shift; 14989 break; 14990 case TCP_RACK_REORD_FADE: 14991 /* Does reordering fade after ms time */ 14992 optval = bbr->r_ctl.rc_reorder_fade; 14993 break; 14994 case TCP_BBR_USE_RACK_CHEAT: 14995 /* Do we use the rack cheat for rxt */ 14996 optval = bbr->bbr_use_rack_cheat; 14997 break; 14998 case TCP_BBR_FLOOR_MIN_TSO: 14999 optval = bbr->r_ctl.bbr_hptsi_segments_floor; 15000 break; 15001 case TCP_BBR_UTTER_MAX_TSO: 15002 optval = bbr->r_ctl.bbr_utter_max; 15003 break; 15004 case TCP_BBR_SEND_IWND_IN_TSO: 15005 /* Do we send TSO size segments initially */ 15006 optval = bbr->bbr_init_win_cheat; 15007 break; 15008 case TCP_BBR_EXTRA_STATE: 15009 optval = bbr->rc_use_idle_restart; 15010 break; 15011 case TCP_RACK_TLP_THRESH: 15012 /* RACK TLP theshold i.e. srtt+(srtt/N) */ 15013 optval = bbr->rc_tlp_threshold; 15014 break; 15015 case TCP_RACK_PKT_DELAY: 15016 /* RACK added ms i.e. rack-rtt + reord + N */ 15017 optval = bbr->r_ctl.rc_pkt_delay; 15018 break; 15019 case TCP_BBR_RETRAN_WTSO: 15020 optval = bbr->rc_resends_use_tso; 15021 break; 15022 case TCP_DATA_AFTER_CLOSE: 15023 optval = bbr->rc_allow_data_af_clo; 15024 break; 15025 case TCP_DELACK: 15026 optval = tp->t_delayed_ack; 15027 break; 15028 case TCP_BBR_HDWR_PACE: 15029 optval = bbr->bbr_hdw_pace_ena; 15030 break; 15031 case TCP_BBR_POLICER_DETECT: 15032 optval = bbr->r_use_policer; 15033 break; 15034 case TCP_BBR_TSTMP_RAISES: 15035 optval = bbr->ts_can_raise; 15036 break; 15037 case TCP_BBR_TMR_PACE_OH: 15038 optval = bbr->r_ctl.rc_incr_tmrs; 15039 break; 15040 case TCP_BBR_PACE_OH: 15041 optval = 0; 15042 if (bbr->r_ctl.rc_inc_tcp_oh) 15043 optval |= BBR_INCL_TCP_OH; 15044 if (bbr->r_ctl.rc_inc_ip_oh) 15045 optval |= BBR_INCL_IP_OH; 15046 if (bbr->r_ctl.rc_inc_enet_oh) 15047 optval |= BBR_INCL_ENET_OH; 15048 break; 15049 default: 15050 return (tcp_default_ctloutput(so, sopt, inp, tp)); 15051 break; 15052 } 15053 INP_WUNLOCK(inp); 15054 error = sooptcopyout(sopt, &optval, sizeof optval); 15055 return (error); 15056 } 15057 15058 /* 15059 * return 0 on success, error-num on failure 15060 */ 15061 static int 15062 bbr_ctloutput(struct socket *so, struct sockopt *sopt, struct inpcb *inp, struct tcpcb *tp) 15063 { 15064 int32_t error = EINVAL; 15065 struct tcp_bbr *bbr; 15066 15067 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 15068 if (bbr == NULL) { 15069 /* Huh? */ 15070 goto out; 15071 } 15072 if (sopt->sopt_dir == SOPT_SET) { 15073 return (bbr_set_sockopt(so, sopt, inp, tp, bbr)); 15074 } else if (sopt->sopt_dir == SOPT_GET) { 15075 return (bbr_get_sockopt(so, sopt, inp, tp, bbr)); 15076 } 15077 out: 15078 INP_WUNLOCK(inp); 15079 return (error); 15080 } 15081 15082 15083 struct tcp_function_block __tcp_bbr = { 15084 .tfb_tcp_block_name = __XSTRING(STACKNAME), 15085 .tfb_tcp_output = bbr_output, 15086 .tfb_do_queued_segments = ctf_do_queued_segments, 15087 .tfb_do_segment_nounlock = bbr_do_segment_nounlock, 15088 .tfb_tcp_do_segment = bbr_do_segment, 15089 .tfb_tcp_ctloutput = bbr_ctloutput, 15090 .tfb_tcp_fb_init = bbr_init, 15091 .tfb_tcp_fb_fini = bbr_fini, 15092 .tfb_tcp_timer_stop_all = bbr_stopall, 15093 .tfb_tcp_timer_activate = bbr_timer_activate, 15094 .tfb_tcp_timer_active = bbr_timer_active, 15095 .tfb_tcp_timer_stop = bbr_timer_stop, 15096 .tfb_tcp_rexmit_tmr = bbr_remxt_tmr, 15097 .tfb_tcp_handoff_ok = bbr_handoff_ok, 15098 .tfb_tcp_mtu_chg = bbr_mtu_chg 15099 }; 15100 15101 static const char *bbr_stack_names[] = { 15102 __XSTRING(STACKNAME), 15103 #ifdef STACKALIAS 15104 __XSTRING(STACKALIAS), 15105 #endif 15106 }; 15107 15108 static bool bbr_mod_inited = false; 15109 15110 static int 15111 tcp_addbbr(module_t mod, int32_t type, void *data) 15112 { 15113 int32_t err = 0; 15114 int num_stacks; 15115 15116 switch (type) { 15117 case MOD_LOAD: 15118 printf("Attempting to load " __XSTRING(MODNAME) "\n"); 15119 bbr_zone = uma_zcreate(__XSTRING(MODNAME) "_map", 15120 sizeof(struct bbr_sendmap), 15121 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 15122 bbr_pcb_zone = uma_zcreate(__XSTRING(MODNAME) "_pcb", 15123 sizeof(struct tcp_bbr), 15124 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0); 15125 sysctl_ctx_init(&bbr_sysctl_ctx); 15126 bbr_sysctl_root = SYSCTL_ADD_NODE(&bbr_sysctl_ctx, 15127 SYSCTL_STATIC_CHILDREN(_net_inet_tcp), 15128 OID_AUTO, 15129 #ifdef STACKALIAS 15130 __XSTRING(STACKALIAS), 15131 #else 15132 __XSTRING(STACKNAME), 15133 #endif 15134 CTLFLAG_RW, 0, 15135 ""); 15136 if (bbr_sysctl_root == NULL) { 15137 printf("Failed to add sysctl node\n"); 15138 err = EFAULT; 15139 goto free_uma; 15140 } 15141 bbr_init_sysctls(); 15142 num_stacks = nitems(bbr_stack_names); 15143 err = register_tcp_functions_as_names(&__tcp_bbr, M_WAITOK, 15144 bbr_stack_names, &num_stacks); 15145 if (err) { 15146 printf("Failed to register %s stack name for " 15147 "%s module\n", bbr_stack_names[num_stacks], 15148 __XSTRING(MODNAME)); 15149 sysctl_ctx_free(&bbr_sysctl_ctx); 15150 free_uma: 15151 uma_zdestroy(bbr_zone); 15152 uma_zdestroy(bbr_pcb_zone); 15153 bbr_counter_destroy(); 15154 printf("Failed to register " __XSTRING(MODNAME) 15155 " module err:%d\n", err); 15156 return (err); 15157 } 15158 tcp_lro_reg_mbufq(); 15159 bbr_mod_inited = true; 15160 printf(__XSTRING(MODNAME) " is now available\n"); 15161 break; 15162 case MOD_QUIESCE: 15163 err = deregister_tcp_functions(&__tcp_bbr, true, false); 15164 break; 15165 case MOD_UNLOAD: 15166 err = deregister_tcp_functions(&__tcp_bbr, false, true); 15167 if (err == EBUSY) 15168 break; 15169 if (bbr_mod_inited) { 15170 uma_zdestroy(bbr_zone); 15171 uma_zdestroy(bbr_pcb_zone); 15172 sysctl_ctx_free(&bbr_sysctl_ctx); 15173 bbr_counter_destroy(); 15174 printf(__XSTRING(MODNAME) 15175 " is now no longer available\n"); 15176 bbr_mod_inited = false; 15177 } 15178 tcp_lro_dereg_mbufq(); 15179 err = 0; 15180 break; 15181 default: 15182 return (EOPNOTSUPP); 15183 } 15184 return (err); 15185 } 15186 15187 static moduledata_t tcp_bbr = { 15188 .name = __XSTRING(MODNAME), 15189 .evhand = tcp_addbbr, 15190 .priv = 0 15191 }; 15192 15193 MODULE_VERSION(MODNAME, 1); 15194 DECLARE_MODULE(MODNAME, tcp_bbr, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY); 15195 MODULE_DEPEND(MODNAME, tcphpts, 1, 1, 1); 15196