1 /*- 2 * Copyright (c) 2016-2020 Netflix, Inc. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23 * SUCH DAMAGE. 24 * 25 */ 26 /** 27 * Author: Randall Stewart <rrs@netflix.com> 28 * This work is based on the ACM Queue paper 29 * BBR - Congestion Based Congestion Control 30 * and also numerous discussions with Neal, Yuchung and Van. 31 */ 32 33 #include <sys/cdefs.h> 34 __FBSDID("$FreeBSD$"); 35 36 #include "opt_inet.h" 37 #include "opt_inet6.h" 38 #include "opt_ipsec.h" 39 #include "opt_tcpdebug.h" 40 #include "opt_ratelimit.h" 41 #include <sys/param.h> 42 #include <sys/arb.h> 43 #include <sys/module.h> 44 #include <sys/kernel.h> 45 #include <sys/libkern.h> 46 #ifdef TCP_HHOOK 47 #include <sys/hhook.h> 48 #endif 49 #include <sys/malloc.h> 50 #include <sys/mbuf.h> 51 #include <sys/proc.h> 52 #include <sys/socket.h> 53 #include <sys/socketvar.h> 54 #include <sys/sysctl.h> 55 #include <sys/systm.h> 56 #ifdef STATS 57 #include <sys/qmath.h> 58 #include <sys/tree.h> 59 #include <sys/stats.h> /* Must come after qmath.h and tree.h */ 60 #endif 61 #include <sys/refcount.h> 62 #include <sys/queue.h> 63 #include <sys/eventhandler.h> 64 #include <sys/smp.h> 65 #include <sys/kthread.h> 66 #include <sys/lock.h> 67 #include <sys/mutex.h> 68 #include <sys/tim_filter.h> 69 #include <sys/time.h> 70 #include <sys/protosw.h> 71 #include <vm/uma.h> 72 #include <sys/kern_prefetch.h> 73 74 #include <net/route.h> 75 #include <net/route/nhop.h> 76 #include <net/vnet.h> 77 78 #define TCPSTATES /* for logging */ 79 80 #include <netinet/in.h> 81 #include <netinet/in_kdtrace.h> 82 #include <netinet/in_pcb.h> 83 #include <netinet/ip.h> 84 #include <netinet/ip_icmp.h> /* required for icmp_var.h */ 85 #include <netinet/icmp_var.h> /* for ICMP_BANDLIM */ 86 #include <netinet/ip_var.h> 87 #include <netinet/ip6.h> 88 #include <netinet6/in6_pcb.h> 89 #include <netinet6/ip6_var.h> 90 #define TCPOUTFLAGS 91 #include <netinet/tcp.h> 92 #include <netinet/tcp_fsm.h> 93 #include <netinet/tcp_seq.h> 94 #include <netinet/tcp_timer.h> 95 #include <netinet/tcp_var.h> 96 #include <netinet/tcpip.h> 97 #include <netinet/tcp_hpts.h> 98 #include <netinet/cc/cc.h> 99 #include <netinet/tcp_log_buf.h> 100 #include <netinet/tcp_ratelimit.h> 101 #include <netinet/tcp_lro.h> 102 #ifdef TCPDEBUG 103 #include <netinet/tcp_debug.h> 104 #endif /* TCPDEBUG */ 105 #ifdef TCP_OFFLOAD 106 #include <netinet/tcp_offload.h> 107 #endif 108 #ifdef INET6 109 #include <netinet6/tcp6_var.h> 110 #endif 111 #include <netinet/tcp_fastopen.h> 112 113 #include <netipsec/ipsec_support.h> 114 #include <net/if.h> 115 #include <net/if_var.h> 116 #include <net/ethernet.h> 117 118 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 119 #include <netipsec/ipsec.h> 120 #include <netipsec/ipsec6.h> 121 #endif /* IPSEC */ 122 123 #include <netinet/udp.h> 124 #include <netinet/udp_var.h> 125 #include <machine/in_cksum.h> 126 127 #ifdef MAC 128 #include <security/mac/mac_framework.h> 129 #endif 130 131 #include "sack_filter.h" 132 #include "tcp_bbr.h" 133 #include "rack_bbr_common.h" 134 uma_zone_t bbr_zone; 135 uma_zone_t bbr_pcb_zone; 136 137 struct sysctl_ctx_list bbr_sysctl_ctx; 138 struct sysctl_oid *bbr_sysctl_root; 139 140 #define TCPT_RANGESET_NOSLOP(tv, value, tvmin, tvmax) do { \ 141 (tv) = (value); \ 142 if ((u_long)(tv) < (u_long)(tvmin)) \ 143 (tv) = (tvmin); \ 144 if ((u_long)(tv) > (u_long)(tvmax)) \ 145 (tv) = (tvmax); \ 146 } while(0) 147 148 /*#define BBR_INVARIANT 1*/ 149 150 /* 151 * initial window 152 */ 153 static uint32_t bbr_def_init_win = 10; 154 static int32_t bbr_persist_min = 250000; /* 250ms */ 155 static int32_t bbr_persist_max = 1000000; /* 1 Second */ 156 static int32_t bbr_cwnd_may_shrink = 0; 157 static int32_t bbr_cwndtarget_rtt_touse = BBR_RTT_PROP; 158 static int32_t bbr_num_pktepo_for_del_limit = BBR_NUM_RTTS_FOR_DEL_LIMIT; 159 static int32_t bbr_hardware_pacing_limit = 8000; 160 static int32_t bbr_quanta = 3; /* How much extra quanta do we get? */ 161 static int32_t bbr_no_retran = 0; 162 163 static int32_t bbr_error_base_paceout = 10000; /* usec to pace */ 164 static int32_t bbr_max_net_error_cnt = 10; 165 /* Should the following be dynamic too -- loss wise */ 166 static int32_t bbr_rtt_gain_thresh = 0; 167 /* Measurement controls */ 168 static int32_t bbr_use_google_algo = 1; 169 static int32_t bbr_ts_limiting = 1; 170 static int32_t bbr_ts_can_raise = 0; 171 static int32_t bbr_do_red = 600; 172 static int32_t bbr_red_scale = 20000; 173 static int32_t bbr_red_mul = 1; 174 static int32_t bbr_red_div = 2; 175 static int32_t bbr_red_growth_restrict = 1; 176 static int32_t bbr_target_is_bbunit = 0; 177 static int32_t bbr_drop_limit = 0; 178 /* 179 * How much gain do we need to see to 180 * stay in startup? 181 */ 182 static int32_t bbr_marks_rxt_sack_passed = 0; 183 static int32_t bbr_start_exit = 25; 184 static int32_t bbr_low_start_exit = 25; /* When we are in reduced gain */ 185 static int32_t bbr_startup_loss_thresh = 2000; /* 20.00% loss */ 186 static int32_t bbr_hptsi_max_mul = 1; /* These two mul/div assure a min pacing */ 187 static int32_t bbr_hptsi_max_div = 2; /* time, 0 means turned off. We need this 188 * if we go back ever to where the pacer 189 * has priority over timers. 190 */ 191 static int32_t bbr_policer_call_from_rack_to = 0; 192 static int32_t bbr_policer_detection_enabled = 1; 193 static int32_t bbr_min_measurements_req = 1; /* We need at least 2 194 * measurments before we are 195 * "good" note that 2 == 1. 196 * This is because we use a > 197 * comparison. This means if 198 * min_measure was 0, it takes 199 * num-measures > min(0) and 200 * you get 1 measurement and 201 * you are good. Set to 1, you 202 * have to have two 203 * measurements (this is done 204 * to prevent it from being ok 205 * to have no measurements). */ 206 static int32_t bbr_no_pacing_until = 4; 207 208 static int32_t bbr_min_usec_delta = 20000; /* 20,000 usecs */ 209 static int32_t bbr_min_peer_delta = 20; /* 20 units */ 210 static int32_t bbr_delta_percent = 150; /* 15.0 % */ 211 212 static int32_t bbr_target_cwnd_mult_limit = 8; 213 /* 214 * bbr_cwnd_min_val is the number of 215 * segments we hold to in the RTT probe 216 * state typically 4. 217 */ 218 static int32_t bbr_cwnd_min_val = BBR_PROBERTT_NUM_MSS; 219 220 static int32_t bbr_cwnd_min_val_hs = BBR_HIGHSPEED_NUM_MSS; 221 222 static int32_t bbr_gain_to_target = 1; 223 static int32_t bbr_gain_gets_extra_too = 1; 224 /* 225 * bbr_high_gain is the 2/ln(2) value we need 226 * to double the sending rate in startup. This 227 * is used for both cwnd and hptsi gain's. 228 */ 229 static int32_t bbr_high_gain = BBR_UNIT * 2885 / 1000 + 1; 230 static int32_t bbr_startup_lower = BBR_UNIT * 1500 / 1000 + 1; 231 static int32_t bbr_use_lower_gain_in_startup = 1; 232 233 /* thresholds for reduction on drain in sub-states/drain */ 234 static int32_t bbr_drain_rtt = BBR_SRTT; 235 static int32_t bbr_drain_floor = 88; 236 static int32_t google_allow_early_out = 1; 237 static int32_t google_consider_lost = 1; 238 static int32_t bbr_drain_drop_mul = 4; 239 static int32_t bbr_drain_drop_div = 5; 240 static int32_t bbr_rand_ot = 50; 241 static int32_t bbr_can_force_probertt = 0; 242 static int32_t bbr_can_adjust_probertt = 1; 243 static int32_t bbr_probertt_sets_rtt = 0; 244 static int32_t bbr_can_use_ts_for_rtt = 1; 245 static int32_t bbr_is_ratio = 0; 246 static int32_t bbr_sub_drain_app_limit = 1; 247 static int32_t bbr_prtt_slam_cwnd = 1; 248 static int32_t bbr_sub_drain_slam_cwnd = 1; 249 static int32_t bbr_slam_cwnd_in_main_drain = 1; 250 static int32_t bbr_filter_len_sec = 6; /* How long does the rttProp filter 251 * hold */ 252 static uint32_t bbr_rtt_probe_limit = (USECS_IN_SECOND * 4); 253 /* 254 * bbr_drain_gain is the reverse of the high_gain 255 * designed to drain back out the standing queue 256 * that is formed in startup by causing a larger 257 * hptsi gain and thus drainging the packets 258 * in flight. 259 */ 260 static int32_t bbr_drain_gain = BBR_UNIT * 1000 / 2885; 261 static int32_t bbr_rttprobe_gain = 192; 262 263 /* 264 * The cwnd_gain is the default cwnd gain applied when 265 * calculating a target cwnd. Note that the cwnd is 266 * a secondary factor in the way BBR works (see the 267 * paper and think about it, it will take some time). 268 * Basically the hptsi_gain spreads the packets out 269 * so you never get more than BDP to the peer even 270 * if the cwnd is high. In our implemenation that 271 * means in non-recovery/retransmission scenarios 272 * cwnd will never be reached by the flight-size. 273 */ 274 static int32_t bbr_cwnd_gain = BBR_UNIT * 2; 275 static int32_t bbr_tlp_type_to_use = BBR_SRTT; 276 static int32_t bbr_delack_time = 100000; /* 100ms in useconds */ 277 static int32_t bbr_sack_not_required = 0; /* set to one to allow non-sack to use bbr */ 278 static int32_t bbr_initial_bw_bps = 62500; /* 500kbps in bytes ps */ 279 static int32_t bbr_ignore_data_after_close = 1; 280 static int16_t bbr_hptsi_gain[] = { 281 (BBR_UNIT *5 / 4), 282 (BBR_UNIT * 3 / 4), 283 BBR_UNIT, 284 BBR_UNIT, 285 BBR_UNIT, 286 BBR_UNIT, 287 BBR_UNIT, 288 BBR_UNIT 289 }; 290 int32_t bbr_use_rack_resend_cheat = 1; 291 int32_t bbr_sends_full_iwnd = 1; 292 293 #define BBR_HPTSI_GAIN_MAX 8 294 /* 295 * The BBR module incorporates a number of 296 * TCP ideas that have been put out into the IETF 297 * over the last few years: 298 * - Yuchung Cheng's RACK TCP (for which its named) that 299 * will stop us using the number of dup acks and instead 300 * use time as the gage of when we retransmit. 301 * - Reorder Detection of RFC4737 and the Tail-Loss probe draft 302 * of Dukkipati et.al. 303 * - Van Jacobson's et.al BBR. 304 * 305 * RACK depends on SACK, so if an endpoint arrives that 306 * cannot do SACK the state machine below will shuttle the 307 * connection back to using the "default" TCP stack that is 308 * in FreeBSD. 309 * 310 * To implement BBR and RACK the original TCP stack was first decomposed 311 * into a functional state machine with individual states 312 * for each of the possible TCP connection states. The do_segement 313 * functions role in life is to mandate the connection supports SACK 314 * initially and then assure that the RACK state matches the conenction 315 * state before calling the states do_segment function. Data processing 316 * of inbound segments also now happens in the hpts_do_segment in general 317 * with only one exception. This is so we can keep the connection on 318 * a single CPU. 319 * 320 * Each state is simplified due to the fact that the original do_segment 321 * has been decomposed and we *know* what state we are in (no 322 * switches on the state) and all tests for SACK are gone. This 323 * greatly simplifies what each state does. 324 * 325 * TCP output is also over-written with a new version since it 326 * must maintain the new rack scoreboard and has had hptsi 327 * integrated as a requirment. Still todo is to eliminate the 328 * use of the callout_() system and use the hpts for all 329 * timers as well. 330 */ 331 static uint32_t bbr_rtt_probe_time = 200000; /* 200ms in micro seconds */ 332 static uint32_t bbr_rtt_probe_cwndtarg = 4; /* How many mss's outstanding */ 333 static const int32_t bbr_min_req_free = 2; /* The min we must have on the 334 * free list */ 335 static int32_t bbr_tlp_thresh = 1; 336 static int32_t bbr_reorder_thresh = 2; 337 static int32_t bbr_reorder_fade = 60000000; /* 0 - never fade, def 338 * 60,000,000 - 60 seconds */ 339 static int32_t bbr_pkt_delay = 1000; 340 static int32_t bbr_min_to = 1000; /* Number of usec's minimum timeout */ 341 static int32_t bbr_incr_timers = 1; 342 343 static int32_t bbr_tlp_min = 10000; /* 10ms in usecs */ 344 static int32_t bbr_delayed_ack_time = 200000; /* 200ms in usecs */ 345 static int32_t bbr_exit_startup_at_loss = 1; 346 347 /* 348 * bbr_lt_bw_ratio is 1/8th 349 * bbr_lt_bw_diff is < 4 Kbit/sec 350 */ 351 static uint64_t bbr_lt_bw_diff = 4000 / 8; /* In bytes per second */ 352 static uint64_t bbr_lt_bw_ratio = 8; /* For 1/8th */ 353 static uint32_t bbr_lt_bw_max_rtts = 48; /* How many rtt's do we use 354 * the lt_bw for */ 355 static uint32_t bbr_lt_intvl_min_rtts = 4; /* Min num of RTT's to measure 356 * lt_bw */ 357 static int32_t bbr_lt_intvl_fp = 0; /* False positive epoch diff */ 358 static int32_t bbr_lt_loss_thresh = 196; /* Lost vs delivered % */ 359 static int32_t bbr_lt_fd_thresh = 100; /* false detection % */ 360 361 static int32_t bbr_verbose_logging = 0; 362 /* 363 * Currently regular tcp has a rto_min of 30ms 364 * the backoff goes 12 times so that ends up 365 * being a total of 122.850 seconds before a 366 * connection is killed. 367 */ 368 static int32_t bbr_rto_min_ms = 30; /* 30ms same as main freebsd */ 369 static int32_t bbr_rto_max_sec = 4; /* 4 seconds */ 370 371 /****************************************************/ 372 /* DEFAULT TSO SIZING (cpu performance impacting) */ 373 /****************************************************/ 374 /* What amount is our formula using to get TSO size */ 375 static int32_t bbr_hptsi_per_second = 1000; 376 377 /* 378 * For hptsi under bbr_cross_over connections what is delay 379 * target 7ms (in usec) combined with a seg_max of 2 380 * gets us close to identical google behavior in 381 * TSO size selection (possibly more 1MSS sends). 382 */ 383 static int32_t bbr_hptsi_segments_delay_tar = 7000; 384 385 /* Does pacing delay include overhead's in its time calculations? */ 386 static int32_t bbr_include_enet_oh = 0; 387 static int32_t bbr_include_ip_oh = 1; 388 static int32_t bbr_include_tcp_oh = 1; 389 static int32_t bbr_google_discount = 10; 390 391 /* Do we use (nf mode) pkt-epoch to drive us or rttProp? */ 392 static int32_t bbr_state_is_pkt_epoch = 0; 393 static int32_t bbr_state_drain_2_tar = 1; 394 /* What is the max the 0 - bbr_cross_over MBPS TSO target 395 * can reach using our delay target. Note that this 396 * value becomes the floor for the cross over 397 * algorithm. 398 */ 399 static int32_t bbr_hptsi_segments_max = 2; 400 static int32_t bbr_hptsi_segments_floor = 1; 401 static int32_t bbr_hptsi_utter_max = 0; 402 403 /* What is the min the 0 - bbr_cross-over MBPS TSO target can be */ 404 static int32_t bbr_hptsi_bytes_min = 1460; 405 static int32_t bbr_all_get_min = 0; 406 407 /* Cross over point from algo-a to algo-b */ 408 static uint32_t bbr_cross_over = TWENTY_THREE_MBPS; 409 410 /* Do we deal with our restart state? */ 411 static int32_t bbr_uses_idle_restart = 0; 412 static int32_t bbr_idle_restart_threshold = 100000; /* 100ms in useconds */ 413 414 /* Do we allow hardware pacing? */ 415 static int32_t bbr_allow_hdwr_pacing = 0; 416 static int32_t bbr_hdwr_pace_adjust = 2; /* multipler when we calc the tso size */ 417 static int32_t bbr_hdwr_pace_floor = 1; 418 static int32_t bbr_hdwr_pacing_delay_cnt = 10; 419 420 /****************************************************/ 421 static int32_t bbr_resends_use_tso = 0; 422 static int32_t bbr_tlp_max_resend = 2; 423 static int32_t bbr_sack_block_limit = 128; 424 425 #define BBR_MAX_STAT 19 426 counter_u64_t bbr_state_time[BBR_MAX_STAT]; 427 counter_u64_t bbr_state_lost[BBR_MAX_STAT]; 428 counter_u64_t bbr_state_resend[BBR_MAX_STAT]; 429 counter_u64_t bbr_stat_arry[BBR_STAT_SIZE]; 430 counter_u64_t bbr_opts_arry[BBR_OPTS_SIZE]; 431 counter_u64_t bbr_out_size[TCP_MSS_ACCT_SIZE]; 432 counter_u64_t bbr_flows_whdwr_pacing; 433 counter_u64_t bbr_flows_nohdwr_pacing; 434 435 counter_u64_t bbr_nohdwr_pacing_enobuf; 436 counter_u64_t bbr_hdwr_pacing_enobuf; 437 438 static inline uint64_t bbr_get_bw(struct tcp_bbr *bbr); 439 440 /* 441 * Static defintions we need for forward declarations. 442 */ 443 static uint32_t 444 bbr_get_pacing_length(struct tcp_bbr *bbr, uint16_t gain, 445 uint32_t useconds_time, uint64_t bw); 446 static uint32_t 447 bbr_get_a_state_target(struct tcp_bbr *bbr, uint32_t gain); 448 static void 449 bbr_set_state(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t win); 450 static void 451 bbr_set_probebw_gains(struct tcp_bbr *bbr, uint32_t cts, uint32_t losses); 452 static void 453 bbr_substate_change(struct tcp_bbr *bbr, uint32_t cts, int line, 454 int dolog); 455 static uint32_t 456 bbr_get_target_cwnd(struct tcp_bbr *bbr, uint64_t bw, uint32_t gain); 457 static void 458 bbr_state_change(struct tcp_bbr *bbr, uint32_t cts, int32_t epoch, 459 int32_t pkt_epoch, uint32_t losses); 460 static uint32_t 461 bbr_calc_thresh_rack(struct tcp_bbr *bbr, uint32_t srtt, uint32_t cts, struct bbr_sendmap *rsm); 462 static uint32_t bbr_initial_cwnd(struct tcp_bbr *bbr, struct tcpcb *tp); 463 static uint32_t 464 bbr_calc_thresh_tlp(struct tcpcb *tp, struct tcp_bbr *bbr, 465 struct bbr_sendmap *rsm, uint32_t srtt, 466 uint32_t cts); 467 static void 468 bbr_exit_persist(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts, 469 int32_t line); 470 static void 471 bbr_set_state_target(struct tcp_bbr *bbr, int line); 472 static void 473 bbr_enter_probe_rtt(struct tcp_bbr *bbr, uint32_t cts, int32_t line); 474 475 static void 476 bbr_log_progress_event(struct tcp_bbr *bbr, struct tcpcb *tp, uint32_t tick, int event, int line); 477 478 static void 479 tcp_bbr_tso_size_check(struct tcp_bbr *bbr, uint32_t cts); 480 481 static void 482 bbr_setup_red_bw(struct tcp_bbr *bbr, uint32_t cts); 483 484 static void 485 bbr_log_rtt_shrinks(struct tcp_bbr *bbr, uint32_t cts, uint32_t applied, uint32_t rtt, 486 uint32_t line, uint8_t is_start, uint16_t set); 487 488 static struct bbr_sendmap * 489 bbr_find_lowest_rsm(struct tcp_bbr *bbr); 490 static __inline uint32_t 491 bbr_get_rtt(struct tcp_bbr *bbr, int32_t rtt_type); 492 static void 493 bbr_log_to_start(struct tcp_bbr *bbr, uint32_t cts, uint32_t to, int32_t slot, uint8_t which); 494 495 static void 496 bbr_log_timer_var(struct tcp_bbr *bbr, int mode, uint32_t cts, uint32_t time_since_sent, uint32_t srtt, 497 uint32_t thresh, uint32_t to); 498 static void 499 bbr_log_hpts_diag(struct tcp_bbr *bbr, uint32_t cts, struct hpts_diag *diag); 500 501 static void 502 bbr_log_type_bbrsnd(struct tcp_bbr *bbr, uint32_t len, uint32_t slot, 503 uint32_t del_by, uint32_t cts, uint32_t sloton, uint32_t prev_delay); 504 505 static void 506 bbr_enter_persist(struct tcpcb *tp, struct tcp_bbr *bbr, 507 uint32_t cts, int32_t line); 508 static void 509 bbr_stop_all_timers(struct tcpcb *tp); 510 static void 511 bbr_exit_probe_rtt(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts); 512 static void 513 bbr_check_probe_rtt_limits(struct tcp_bbr *bbr, uint32_t cts); 514 static void 515 bbr_timer_cancel(struct tcp_bbr *bbr, int32_t line, uint32_t cts); 516 517 static void 518 bbr_log_pacing_delay_calc(struct tcp_bbr *bbr, uint16_t gain, uint32_t len, 519 uint32_t cts, uint32_t usecs, uint64_t bw, uint32_t override, int mod); 520 521 static inline uint8_t 522 bbr_state_val(struct tcp_bbr *bbr) 523 { 524 return(bbr->rc_bbr_substate); 525 } 526 527 static inline uint32_t 528 get_min_cwnd(struct tcp_bbr *bbr) 529 { 530 int mss; 531 532 mss = min((bbr->rc_tp->t_maxseg - bbr->rc_last_options), bbr->r_ctl.rc_pace_max_segs); 533 if (bbr_get_rtt(bbr, BBR_RTT_PROP) < BBR_HIGH_SPEED) 534 return (bbr_cwnd_min_val_hs * mss); 535 else 536 return (bbr_cwnd_min_val * mss); 537 } 538 539 static uint32_t 540 bbr_get_persists_timer_val(struct tcpcb *tp, struct tcp_bbr *bbr) 541 { 542 uint64_t srtt, var; 543 uint64_t ret_val; 544 545 bbr->r_ctl.rc_hpts_flags |= PACE_TMR_PERSIT; 546 if (tp->t_srtt == 0) { 547 srtt = (uint64_t)BBR_INITIAL_RTO; 548 var = 0; 549 } else { 550 srtt = ((uint64_t)TICKS_2_USEC(tp->t_srtt) >> TCP_RTT_SHIFT); 551 var = ((uint64_t)TICKS_2_USEC(tp->t_rttvar) >> TCP_RTT_SHIFT); 552 } 553 TCPT_RANGESET_NOSLOP(ret_val, ((srtt + var) * tcp_backoff[tp->t_rxtshift]), 554 bbr_persist_min, bbr_persist_max); 555 return ((uint32_t)ret_val); 556 } 557 558 static uint32_t 559 bbr_timer_start(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts) 560 { 561 /* 562 * Start the FR timer, we do this based on getting the first one in 563 * the rc_tmap. Note that if its NULL we must stop the timer. in all 564 * events we need to stop the running timer (if its running) before 565 * starting the new one. 566 */ 567 uint32_t thresh, exp, to, srtt, time_since_sent, tstmp_touse; 568 int32_t idx; 569 int32_t is_tlp_timer = 0; 570 struct bbr_sendmap *rsm; 571 572 if (bbr->rc_all_timers_stopped) { 573 /* All timers have been stopped none are to run */ 574 return (0); 575 } 576 if (bbr->rc_in_persist) { 577 /* We can't start any timer in persists */ 578 return (bbr_get_persists_timer_val(tp, bbr)); 579 } 580 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_tmap); 581 if ((rsm == NULL) || 582 ((tp->t_flags & TF_SACK_PERMIT) == 0) || 583 (tp->t_state < TCPS_ESTABLISHED)) { 584 /* Nothing on the send map */ 585 activate_rxt: 586 if (SEQ_LT(tp->snd_una, tp->snd_max) || sbavail(&(tp->t_inpcb->inp_socket->so_snd))) { 587 uint64_t tov; 588 589 time_since_sent = 0; 590 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_tmap); 591 if (rsm) { 592 idx = rsm->r_rtr_cnt - 1; 593 if (TSTMP_GEQ(rsm->r_tim_lastsent[idx], bbr->r_ctl.rc_tlp_rxt_last_time)) 594 tstmp_touse = rsm->r_tim_lastsent[idx]; 595 else 596 tstmp_touse = bbr->r_ctl.rc_tlp_rxt_last_time; 597 if (TSTMP_GT(tstmp_touse, cts)) 598 time_since_sent = cts - tstmp_touse; 599 } 600 bbr->r_ctl.rc_hpts_flags |= PACE_TMR_RXT; 601 if (tp->t_srtt == 0) 602 tov = BBR_INITIAL_RTO; 603 else 604 tov = ((uint64_t)(TICKS_2_USEC(tp->t_srtt) + 605 ((uint64_t)TICKS_2_USEC(tp->t_rttvar) * (uint64_t)4)) >> TCP_RTT_SHIFT); 606 if (tp->t_rxtshift) 607 tov *= tcp_backoff[tp->t_rxtshift]; 608 if (tov > time_since_sent) 609 tov -= time_since_sent; 610 else 611 tov = bbr->r_ctl.rc_min_to; 612 TCPT_RANGESET_NOSLOP(to, tov, 613 (bbr->r_ctl.rc_min_rto_ms * MS_IN_USEC), 614 (bbr->rc_max_rto_sec * USECS_IN_SECOND)); 615 bbr_log_timer_var(bbr, 2, cts, 0, srtt, 0, to); 616 return (to); 617 } 618 return (0); 619 } 620 if (rsm->r_flags & BBR_ACKED) { 621 rsm = bbr_find_lowest_rsm(bbr); 622 if (rsm == NULL) { 623 /* No lowest? */ 624 goto activate_rxt; 625 } 626 } 627 /* Convert from ms to usecs */ 628 if (rsm->r_flags & BBR_SACK_PASSED) { 629 if ((tp->t_flags & TF_SENTFIN) && 630 ((tp->snd_max - tp->snd_una) == 1) && 631 (rsm->r_flags & BBR_HAS_FIN)) { 632 /* 633 * We don't start a bbr rack timer if all we have is 634 * a FIN outstanding. 635 */ 636 goto activate_rxt; 637 } 638 srtt = bbr_get_rtt(bbr, BBR_RTT_RACK); 639 thresh = bbr_calc_thresh_rack(bbr, srtt, cts, rsm); 640 idx = rsm->r_rtr_cnt - 1; 641 exp = rsm->r_tim_lastsent[idx] + thresh; 642 if (SEQ_GEQ(exp, cts)) { 643 to = exp - cts; 644 if (to < bbr->r_ctl.rc_min_to) { 645 to = bbr->r_ctl.rc_min_to; 646 } 647 } else { 648 to = bbr->r_ctl.rc_min_to; 649 } 650 } else { 651 /* Ok we need to do a TLP not RACK */ 652 if (bbr->rc_tlp_in_progress != 0) { 653 /* 654 * The previous send was a TLP. 655 */ 656 goto activate_rxt; 657 } 658 rsm = TAILQ_LAST_FAST(&bbr->r_ctl.rc_tmap, bbr_sendmap, r_tnext); 659 if (rsm == NULL) { 660 /* We found no rsm to TLP with. */ 661 goto activate_rxt; 662 } 663 if (rsm->r_flags & BBR_HAS_FIN) { 664 /* If its a FIN we don't do TLP */ 665 rsm = NULL; 666 goto activate_rxt; 667 } 668 time_since_sent = 0; 669 idx = rsm->r_rtr_cnt - 1; 670 if (TSTMP_GEQ(rsm->r_tim_lastsent[idx], bbr->r_ctl.rc_tlp_rxt_last_time)) 671 tstmp_touse = rsm->r_tim_lastsent[idx]; 672 else 673 tstmp_touse = bbr->r_ctl.rc_tlp_rxt_last_time; 674 if (TSTMP_GT(tstmp_touse, cts)) 675 time_since_sent = cts - tstmp_touse; 676 is_tlp_timer = 1; 677 srtt = bbr_get_rtt(bbr, bbr_tlp_type_to_use); 678 thresh = bbr_calc_thresh_tlp(tp, bbr, rsm, srtt, cts); 679 if (thresh > time_since_sent) 680 to = thresh - time_since_sent; 681 else 682 to = bbr->r_ctl.rc_min_to; 683 if (to > (((uint32_t)bbr->rc_max_rto_sec) * USECS_IN_SECOND)) { 684 /* 685 * If the TLP time works out to larger than the max 686 * RTO lets not do TLP.. just RTO. 687 */ 688 goto activate_rxt; 689 } 690 if ((bbr->rc_tlp_rtx_out == 1) && 691 (rsm->r_start == bbr->r_ctl.rc_last_tlp_seq)) { 692 /* 693 * Second retransmit of the same TLP 694 * lets not. 695 */ 696 bbr->rc_tlp_rtx_out = 0; 697 goto activate_rxt; 698 } 699 if (rsm->r_start != bbr->r_ctl.rc_last_tlp_seq) { 700 /* 701 * The tail is no longer the last one I did a probe 702 * on 703 */ 704 bbr->r_ctl.rc_tlp_seg_send_cnt = 0; 705 bbr->r_ctl.rc_last_tlp_seq = rsm->r_start; 706 } 707 } 708 if (is_tlp_timer == 0) { 709 BBR_STAT_INC(bbr_to_arm_rack); 710 bbr->r_ctl.rc_hpts_flags |= PACE_TMR_RACK; 711 } else { 712 bbr_log_timer_var(bbr, 1, cts, time_since_sent, srtt, thresh, to); 713 if (bbr->r_ctl.rc_tlp_seg_send_cnt > bbr_tlp_max_resend) { 714 /* 715 * We have exceeded how many times we can retran the 716 * current TLP timer, switch to the RTO timer. 717 */ 718 goto activate_rxt; 719 } else { 720 BBR_STAT_INC(bbr_to_arm_tlp); 721 bbr->r_ctl.rc_hpts_flags |= PACE_TMR_TLP; 722 } 723 } 724 return (to); 725 } 726 727 static inline int32_t 728 bbr_minseg(struct tcp_bbr *bbr) 729 { 730 return (bbr->r_ctl.rc_pace_min_segs - bbr->rc_last_options); 731 } 732 733 static void 734 bbr_start_hpts_timer(struct tcp_bbr *bbr, struct tcpcb *tp, uint32_t cts, int32_t frm, int32_t slot, uint32_t tot_len) 735 { 736 struct inpcb *inp; 737 struct hpts_diag diag; 738 uint32_t delayed_ack = 0; 739 uint32_t left = 0; 740 uint32_t hpts_timeout; 741 uint8_t stopped; 742 int32_t delay_calc = 0; 743 uint32_t prev_delay = 0; 744 745 inp = tp->t_inpcb; 746 if (inp->inp_in_hpts) { 747 /* A previous call is already set up */ 748 return; 749 } 750 if ((tp->t_state == TCPS_CLOSED) || 751 (tp->t_state == TCPS_LISTEN)) { 752 return; 753 } 754 stopped = bbr->rc_tmr_stopped; 755 if (stopped && TSTMP_GT(bbr->r_ctl.rc_timer_exp, cts)) { 756 left = bbr->r_ctl.rc_timer_exp - cts; 757 } 758 bbr->r_ctl.rc_hpts_flags = 0; 759 bbr->r_ctl.rc_timer_exp = 0; 760 prev_delay = bbr->r_ctl.rc_last_delay_val; 761 if (bbr->r_ctl.rc_last_delay_val && 762 (slot == 0)) { 763 /* 764 * If a previous pacer delay was in place we 765 * are not coming from the output side (where 766 * we calculate a delay, more likely a timer). 767 */ 768 slot = bbr->r_ctl.rc_last_delay_val; 769 if (TSTMP_GT(cts, bbr->rc_pacer_started)) { 770 /* Compensate for time passed */ 771 delay_calc = cts - bbr->rc_pacer_started; 772 if (delay_calc <= slot) 773 slot -= delay_calc; 774 } 775 } 776 /* Do we have early to make up for by pushing out the pacing time? */ 777 if (bbr->r_agg_early_set) { 778 bbr_log_pacing_delay_calc(bbr, 0, bbr->r_ctl.rc_agg_early, cts, slot, 0, bbr->r_agg_early_set, 2); 779 slot += bbr->r_ctl.rc_agg_early; 780 bbr->r_ctl.rc_agg_early = 0; 781 bbr->r_agg_early_set = 0; 782 } 783 /* Are we running a total debt that needs to be compensated for? */ 784 if (bbr->r_ctl.rc_hptsi_agg_delay) { 785 if (slot > bbr->r_ctl.rc_hptsi_agg_delay) { 786 /* We nuke the delay */ 787 slot -= bbr->r_ctl.rc_hptsi_agg_delay; 788 bbr->r_ctl.rc_hptsi_agg_delay = 0; 789 } else { 790 /* We nuke some of the delay, put in a minimal 100usecs */ 791 bbr->r_ctl.rc_hptsi_agg_delay -= slot; 792 bbr->r_ctl.rc_last_delay_val = slot = 100; 793 } 794 } 795 bbr->r_ctl.rc_last_delay_val = slot; 796 hpts_timeout = bbr_timer_start(tp, bbr, cts); 797 if (tp->t_flags & TF_DELACK) { 798 if (bbr->rc_in_persist == 0) { 799 delayed_ack = bbr_delack_time; 800 } else { 801 /* 802 * We are in persists and have 803 * gotten a new data element. 804 */ 805 if (hpts_timeout > bbr_delack_time) { 806 /* 807 * Lets make the persists timer (which acks) 808 * be the smaller of hpts_timeout and bbr_delack_time. 809 */ 810 hpts_timeout = bbr_delack_time; 811 } 812 } 813 } 814 if (delayed_ack && 815 ((hpts_timeout == 0) || 816 (delayed_ack < hpts_timeout))) { 817 /* We need a Delayed ack timer */ 818 bbr->r_ctl.rc_hpts_flags = PACE_TMR_DELACK; 819 hpts_timeout = delayed_ack; 820 } 821 if (slot) { 822 /* Mark that we have a pacing timer up */ 823 BBR_STAT_INC(bbr_paced_segments); 824 bbr->r_ctl.rc_hpts_flags |= PACE_PKT_OUTPUT; 825 } 826 /* 827 * If no timers are going to run and we will fall off thfe hptsi 828 * wheel, we resort to a keep-alive timer if its configured. 829 */ 830 if ((hpts_timeout == 0) && 831 (slot == 0)) { 832 if ((V_tcp_always_keepalive || inp->inp_socket->so_options & SO_KEEPALIVE) && 833 (tp->t_state <= TCPS_CLOSING)) { 834 /* 835 * Ok we have no timer (persists, rack, tlp, rxt or 836 * del-ack), we don't have segments being paced. So 837 * all that is left is the keepalive timer. 838 */ 839 if (TCPS_HAVEESTABLISHED(tp->t_state)) { 840 hpts_timeout = TICKS_2_USEC(TP_KEEPIDLE(tp)); 841 } else { 842 hpts_timeout = TICKS_2_USEC(TP_KEEPINIT(tp)); 843 } 844 bbr->r_ctl.rc_hpts_flags |= PACE_TMR_KEEP; 845 } 846 } 847 if (left && (stopped & (PACE_TMR_KEEP | PACE_TMR_DELACK)) == 848 (bbr->r_ctl.rc_hpts_flags & PACE_TMR_MASK)) { 849 /* 850 * RACK, TLP, persists and RXT timers all are restartable 851 * based on actions input .. i.e we received a packet (ack 852 * or sack) and that changes things (rw, or snd_una etc). 853 * Thus we can restart them with a new value. For 854 * keep-alive, delayed_ack we keep track of what was left 855 * and restart the timer with a smaller value. 856 */ 857 if (left < hpts_timeout) 858 hpts_timeout = left; 859 } 860 if (bbr->r_ctl.rc_incr_tmrs && slot && 861 (bbr->r_ctl.rc_hpts_flags & (PACE_TMR_TLP|PACE_TMR_RXT))) { 862 /* 863 * If configured to do so, and the timer is either 864 * the TLP or RXT timer, we need to increase the timeout 865 * by the pacing time. Consider the bottleneck at my 866 * machine as an example, we are sending something 867 * to start a TLP on. The last packet won't be emitted 868 * fully until the pacing time (the bottleneck will hold 869 * the data in place). Once the packet is emitted that 870 * is when we want to start waiting for the TLP. This 871 * is most evident with hardware pacing (where the nic 872 * is holding the packet(s) before emitting). But it 873 * can also show up in the network so we do it for all 874 * cases. Technically we would take off one packet from 875 * this extra delay but this is easier and being more 876 * conservative is probably better. 877 */ 878 hpts_timeout += slot; 879 } 880 if (hpts_timeout) { 881 /* 882 * Hack alert for now we can't time-out over 2147 seconds (a 883 * bit more than 35min) 884 */ 885 if (hpts_timeout > 0x7ffffffe) 886 hpts_timeout = 0x7ffffffe; 887 bbr->r_ctl.rc_timer_exp = cts + hpts_timeout; 888 } else 889 bbr->r_ctl.rc_timer_exp = 0; 890 if ((slot) && 891 (bbr->rc_use_google || 892 bbr->output_error_seen || 893 (slot <= hpts_timeout)) ) { 894 /* 895 * Tell LRO that it can queue packets while 896 * we pace. 897 */ 898 bbr->rc_inp->inp_flags2 |= INP_MBUF_QUEUE_READY; 899 if ((bbr->r_ctl.rc_hpts_flags & PACE_TMR_RACK) && 900 (bbr->rc_cwnd_limited == 0)) { 901 /* 902 * If we are not cwnd limited and we 903 * are running a rack timer we put on 904 * the do not disturbe even for sack. 905 */ 906 inp->inp_flags2 |= INP_DONT_SACK_QUEUE; 907 } else 908 inp->inp_flags2 &= ~INP_DONT_SACK_QUEUE; 909 bbr->rc_pacer_started = cts; 910 911 (void)tcp_hpts_insert_diag(tp->t_inpcb, HPTS_USEC_TO_SLOTS(slot), 912 __LINE__, &diag); 913 bbr->rc_timer_first = 0; 914 bbr->bbr_timer_src = frm; 915 bbr_log_to_start(bbr, cts, hpts_timeout, slot, 1); 916 bbr_log_hpts_diag(bbr, cts, &diag); 917 } else if (hpts_timeout) { 918 (void)tcp_hpts_insert_diag(tp->t_inpcb, HPTS_USEC_TO_SLOTS(hpts_timeout), 919 __LINE__, &diag); 920 /* 921 * We add the flag here as well if the slot is set, 922 * since hpts will call in to clear the queue first before 923 * calling the output routine (which does our timers). 924 * We don't want to set the flag if its just a timer 925 * else the arrival of data might (that causes us 926 * to send more) might get delayed. Imagine being 927 * on a keep-alive timer and a request comes in for 928 * more data. 929 */ 930 if (slot) 931 bbr->rc_pacer_started = cts; 932 if ((bbr->r_ctl.rc_hpts_flags & PACE_TMR_RACK) && 933 (bbr->rc_cwnd_limited == 0)) { 934 /* 935 * For a rack timer, don't wake us even 936 * if a sack arrives as long as we are 937 * not cwnd limited. 938 */ 939 bbr->rc_inp->inp_flags2 |= INP_MBUF_QUEUE_READY; 940 inp->inp_flags2 |= INP_DONT_SACK_QUEUE; 941 } else { 942 /* All other timers wake us up */ 943 bbr->rc_inp->inp_flags2 &= ~INP_MBUF_QUEUE_READY; 944 inp->inp_flags2 &= ~INP_DONT_SACK_QUEUE; 945 } 946 bbr->bbr_timer_src = frm; 947 bbr_log_to_start(bbr, cts, hpts_timeout, slot, 0); 948 bbr_log_hpts_diag(bbr, cts, &diag); 949 bbr->rc_timer_first = 1; 950 } 951 bbr->rc_tmr_stopped = 0; 952 bbr_log_type_bbrsnd(bbr, tot_len, slot, delay_calc, cts, frm, prev_delay); 953 } 954 955 static void 956 bbr_timer_audit(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts, struct sockbuf *sb) 957 { 958 /* 959 * We received an ack, and then did not call send or were bounced 960 * out due to the hpts was running. Now a timer is up as well, is it 961 * the right timer? 962 */ 963 struct inpcb *inp; 964 struct bbr_sendmap *rsm; 965 uint32_t hpts_timeout; 966 int tmr_up; 967 968 tmr_up = bbr->r_ctl.rc_hpts_flags & PACE_TMR_MASK; 969 if (bbr->rc_in_persist && (tmr_up == PACE_TMR_PERSIT)) 970 return; 971 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_tmap); 972 if (((rsm == NULL) || (tp->t_state < TCPS_ESTABLISHED)) && 973 (tmr_up == PACE_TMR_RXT)) { 974 /* Should be an RXT */ 975 return; 976 } 977 inp = bbr->rc_inp; 978 if (rsm == NULL) { 979 /* Nothing outstanding? */ 980 if (tp->t_flags & TF_DELACK) { 981 if (tmr_up == PACE_TMR_DELACK) 982 /* 983 * We are supposed to have delayed ack up 984 * and we do 985 */ 986 return; 987 } else if (sbavail(&inp->inp_socket->so_snd) && 988 (tmr_up == PACE_TMR_RXT)) { 989 /* 990 * if we hit enobufs then we would expect the 991 * possiblity of nothing outstanding and the RXT up 992 * (and the hptsi timer). 993 */ 994 return; 995 } else if (((V_tcp_always_keepalive || 996 inp->inp_socket->so_options & SO_KEEPALIVE) && 997 (tp->t_state <= TCPS_CLOSING)) && 998 (tmr_up == PACE_TMR_KEEP) && 999 (tp->snd_max == tp->snd_una)) { 1000 /* We should have keep alive up and we do */ 1001 return; 1002 } 1003 } 1004 if (rsm && (rsm->r_flags & BBR_SACK_PASSED)) { 1005 if ((tp->t_flags & TF_SENTFIN) && 1006 ((tp->snd_max - tp->snd_una) == 1) && 1007 (rsm->r_flags & BBR_HAS_FIN)) { 1008 /* needs to be a RXT */ 1009 if (tmr_up == PACE_TMR_RXT) 1010 return; 1011 else 1012 goto wrong_timer; 1013 } else if (tmr_up == PACE_TMR_RACK) 1014 return; 1015 else 1016 goto wrong_timer; 1017 } else if (rsm && (tmr_up == PACE_TMR_RACK)) { 1018 /* Rack timer has priority if we have data out */ 1019 return; 1020 } else if (SEQ_GT(tp->snd_max, tp->snd_una) && 1021 ((tmr_up == PACE_TMR_TLP) || 1022 (tmr_up == PACE_TMR_RXT))) { 1023 /* 1024 * Either a TLP or RXT is fine if no sack-passed is in place 1025 * and data is outstanding. 1026 */ 1027 return; 1028 } else if (tmr_up == PACE_TMR_DELACK) { 1029 /* 1030 * If the delayed ack was going to go off before the 1031 * rtx/tlp/rack timer were going to expire, then that would 1032 * be the timer in control. Note we don't check the time 1033 * here trusting the code is correct. 1034 */ 1035 return; 1036 } 1037 if (SEQ_GT(tp->snd_max, tp->snd_una) && 1038 ((tmr_up == PACE_TMR_RXT) || 1039 (tmr_up == PACE_TMR_TLP) || 1040 (tmr_up == PACE_TMR_RACK))) { 1041 /* 1042 * We have outstanding data and 1043 * we *do* have a RACK, TLP or RXT 1044 * timer running. We won't restart 1045 * anything here since thats probably ok we 1046 * will get called with some timer here shortly. 1047 */ 1048 return; 1049 } 1050 /* 1051 * Ok the timer originally started is not what we want now. We will 1052 * force the hpts to be stopped if any, and restart with the slot 1053 * set to what was in the saved slot. 1054 */ 1055 wrong_timer: 1056 if ((bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) == 0) { 1057 if (inp->inp_in_hpts) 1058 tcp_hpts_remove(inp, HPTS_REMOVE_OUTPUT); 1059 bbr_timer_cancel(bbr, __LINE__, cts); 1060 bbr_start_hpts_timer(bbr, tp, cts, 1, bbr->r_ctl.rc_last_delay_val, 1061 0); 1062 } else { 1063 /* 1064 * Output is hptsi so we just need to switch the type of 1065 * timer. We don't bother with keep-alive, since when we 1066 * jump through the output, it will start the keep-alive if 1067 * nothing is sent. 1068 * 1069 * We only need a delayed-ack added and or the hpts_timeout. 1070 */ 1071 hpts_timeout = bbr_timer_start(tp, bbr, cts); 1072 if (tp->t_flags & TF_DELACK) { 1073 if (hpts_timeout == 0) { 1074 hpts_timeout = bbr_delack_time; 1075 bbr->r_ctl.rc_hpts_flags = PACE_TMR_DELACK; 1076 } 1077 else if (hpts_timeout > bbr_delack_time) { 1078 hpts_timeout = bbr_delack_time; 1079 bbr->r_ctl.rc_hpts_flags = PACE_TMR_DELACK; 1080 } 1081 } 1082 if (hpts_timeout) { 1083 if (hpts_timeout > 0x7ffffffe) 1084 hpts_timeout = 0x7ffffffe; 1085 bbr->r_ctl.rc_timer_exp = cts + hpts_timeout; 1086 } 1087 } 1088 } 1089 1090 int32_t bbr_clear_lost = 0; 1091 1092 /* 1093 * Considers the two time values now (cts) and earlier. 1094 * If cts is smaller than earlier, we could have 1095 * had a sequence wrap (our counter wraps every 1096 * 70 min or so) or it could be just clock skew 1097 * getting us two differnt time values. Clock skew 1098 * will show up within 10ms or so. So in such 1099 * a case (where cts is behind earlier time by 1100 * less than 10ms) we return 0. Otherwise we 1101 * return the true difference between them. 1102 */ 1103 static inline uint32_t 1104 bbr_calc_time(uint32_t cts, uint32_t earlier_time) { 1105 /* 1106 * Given two timestamps, the current time stamp cts, and some other 1107 * time-stamp taken in theory earlier return the difference. The 1108 * trick is here sometimes locking will get the other timestamp 1109 * after the cts. If this occurs we need to return 0. 1110 */ 1111 if (TSTMP_GEQ(cts, earlier_time)) 1112 return (cts - earlier_time); 1113 /* 1114 * cts is behind earlier_time if its less than 10ms consider it 0. 1115 * If its more than 10ms difference then we had a time wrap. Else 1116 * its just the normal locking foo. I wonder if we should not go to 1117 * 64bit TS and get rid of this issue. 1118 */ 1119 if (TSTMP_GEQ((cts + 10000), earlier_time)) 1120 return (0); 1121 /* 1122 * Ok the time must have wrapped. So we need to answer a large 1123 * amount of time, which the normal subtraction should do. 1124 */ 1125 return (cts - earlier_time); 1126 } 1127 1128 static int 1129 sysctl_bbr_clear_lost(SYSCTL_HANDLER_ARGS) 1130 { 1131 uint32_t stat; 1132 int32_t error; 1133 1134 error = SYSCTL_OUT(req, &bbr_clear_lost, sizeof(uint32_t)); 1135 if (error || req->newptr == NULL) 1136 return error; 1137 1138 error = SYSCTL_IN(req, &stat, sizeof(uint32_t)); 1139 if (error) 1140 return (error); 1141 if (stat == 1) { 1142 #ifdef BBR_INVARIANTS 1143 printf("Clearing BBR lost counters\n"); 1144 #endif 1145 COUNTER_ARRAY_ZERO(bbr_state_lost, BBR_MAX_STAT); 1146 COUNTER_ARRAY_ZERO(bbr_state_time, BBR_MAX_STAT); 1147 COUNTER_ARRAY_ZERO(bbr_state_resend, BBR_MAX_STAT); 1148 } else if (stat == 2) { 1149 #ifdef BBR_INVARIANTS 1150 printf("Clearing BBR option counters\n"); 1151 #endif 1152 COUNTER_ARRAY_ZERO(bbr_opts_arry, BBR_OPTS_SIZE); 1153 } else if (stat == 3) { 1154 #ifdef BBR_INVARIANTS 1155 printf("Clearing BBR stats counters\n"); 1156 #endif 1157 COUNTER_ARRAY_ZERO(bbr_stat_arry, BBR_STAT_SIZE); 1158 } else if (stat == 4) { 1159 #ifdef BBR_INVARIANTS 1160 printf("Clearing BBR out-size counters\n"); 1161 #endif 1162 COUNTER_ARRAY_ZERO(bbr_out_size, TCP_MSS_ACCT_SIZE); 1163 } 1164 bbr_clear_lost = 0; 1165 return (0); 1166 } 1167 1168 static void 1169 bbr_init_sysctls(void) 1170 { 1171 struct sysctl_oid *bbr_probertt; 1172 struct sysctl_oid *bbr_hptsi; 1173 struct sysctl_oid *bbr_measure; 1174 struct sysctl_oid *bbr_cwnd; 1175 struct sysctl_oid *bbr_timeout; 1176 struct sysctl_oid *bbr_states; 1177 struct sysctl_oid *bbr_startup; 1178 struct sysctl_oid *bbr_policer; 1179 1180 /* Probe rtt controls */ 1181 bbr_probertt = SYSCTL_ADD_NODE(&bbr_sysctl_ctx, 1182 SYSCTL_CHILDREN(bbr_sysctl_root), 1183 OID_AUTO, 1184 "probertt", 1185 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1186 ""); 1187 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1188 SYSCTL_CHILDREN(bbr_probertt), 1189 OID_AUTO, "gain", CTLFLAG_RW, 1190 &bbr_rttprobe_gain, 192, 1191 "What is the filter gain drop in probe_rtt (0=disable)?"); 1192 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1193 SYSCTL_CHILDREN(bbr_probertt), 1194 OID_AUTO, "cwnd", CTLFLAG_RW, 1195 &bbr_rtt_probe_cwndtarg, 4, 1196 "How many mss's are outstanding during probe-rtt"); 1197 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1198 SYSCTL_CHILDREN(bbr_probertt), 1199 OID_AUTO, "int", CTLFLAG_RW, 1200 &bbr_rtt_probe_limit, 4000000, 1201 "If RTT has not shrank in this many micro-seconds enter probe-rtt"); 1202 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1203 SYSCTL_CHILDREN(bbr_probertt), 1204 OID_AUTO, "mintime", CTLFLAG_RW, 1205 &bbr_rtt_probe_time, 200000, 1206 "How many microseconds in probe-rtt"); 1207 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1208 SYSCTL_CHILDREN(bbr_probertt), 1209 OID_AUTO, "filter_len_sec", CTLFLAG_RW, 1210 &bbr_filter_len_sec, 6, 1211 "How long in seconds does the rttProp filter run?"); 1212 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1213 SYSCTL_CHILDREN(bbr_probertt), 1214 OID_AUTO, "drain_rtt", CTLFLAG_RW, 1215 &bbr_drain_rtt, BBR_SRTT, 1216 "What is the drain rtt to use in probeRTT (rtt_prop=0, rtt_rack=1, rtt_pkt=2, rtt_srtt=3?"); 1217 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1218 SYSCTL_CHILDREN(bbr_probertt), 1219 OID_AUTO, "can_force", CTLFLAG_RW, 1220 &bbr_can_force_probertt, 0, 1221 "If we keep setting new low rtt's but delay going in probe-rtt can we force in??"); 1222 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1223 SYSCTL_CHILDREN(bbr_probertt), 1224 OID_AUTO, "enter_sets_force", CTLFLAG_RW, 1225 &bbr_probertt_sets_rtt, 0, 1226 "In NF mode, do we imitate google_mode and set the rttProp on entry to probe-rtt?"); 1227 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1228 SYSCTL_CHILDREN(bbr_probertt), 1229 OID_AUTO, "can_adjust", CTLFLAG_RW, 1230 &bbr_can_adjust_probertt, 1, 1231 "Can we dynamically adjust the probe-rtt limits and times?"); 1232 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1233 SYSCTL_CHILDREN(bbr_probertt), 1234 OID_AUTO, "is_ratio", CTLFLAG_RW, 1235 &bbr_is_ratio, 0, 1236 "is the limit to filter a ratio?"); 1237 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1238 SYSCTL_CHILDREN(bbr_probertt), 1239 OID_AUTO, "use_cwnd", CTLFLAG_RW, 1240 &bbr_prtt_slam_cwnd, 0, 1241 "Should we set/recover cwnd?"); 1242 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1243 SYSCTL_CHILDREN(bbr_probertt), 1244 OID_AUTO, "can_use_ts", CTLFLAG_RW, 1245 &bbr_can_use_ts_for_rtt, 1, 1246 "Can we use the ms timestamp if available for retransmistted rtt calculations?"); 1247 1248 /* Pacing controls */ 1249 bbr_hptsi = SYSCTL_ADD_NODE(&bbr_sysctl_ctx, 1250 SYSCTL_CHILDREN(bbr_sysctl_root), 1251 OID_AUTO, 1252 "pacing", 1253 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1254 ""); 1255 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1256 SYSCTL_CHILDREN(bbr_hptsi), 1257 OID_AUTO, "hw_pacing", CTLFLAG_RW, 1258 &bbr_allow_hdwr_pacing, 1, 1259 "Do we allow hardware pacing?"); 1260 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1261 SYSCTL_CHILDREN(bbr_hptsi), 1262 OID_AUTO, "hw_pacing_limit", CTLFLAG_RW, 1263 &bbr_hardware_pacing_limit, 4000, 1264 "Do we have a limited number of connections for pacing chelsio (0=no limit)?"); 1265 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1266 SYSCTL_CHILDREN(bbr_hptsi), 1267 OID_AUTO, "hw_pacing_adj", CTLFLAG_RW, 1268 &bbr_hdwr_pace_adjust, 2, 1269 "Multiplier to calculated tso size?"); 1270 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1271 SYSCTL_CHILDREN(bbr_hptsi), 1272 OID_AUTO, "hw_pacing_floor", CTLFLAG_RW, 1273 &bbr_hdwr_pace_floor, 1, 1274 "Do we invoke the hardware pacing floor?"); 1275 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1276 SYSCTL_CHILDREN(bbr_hptsi), 1277 OID_AUTO, "hw_pacing_delay_cnt", CTLFLAG_RW, 1278 &bbr_hdwr_pacing_delay_cnt, 10, 1279 "How many packets must be sent after hdwr pacing is enabled"); 1280 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1281 SYSCTL_CHILDREN(bbr_hptsi), 1282 OID_AUTO, "bw_cross", CTLFLAG_RW, 1283 &bbr_cross_over, 3000000, 1284 "What is the point where we cross over to linux like TSO size set"); 1285 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1286 SYSCTL_CHILDREN(bbr_hptsi), 1287 OID_AUTO, "seg_deltarg", CTLFLAG_RW, 1288 &bbr_hptsi_segments_delay_tar, 7000, 1289 "What is the worse case delay target for hptsi < 48Mbp connections"); 1290 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1291 SYSCTL_CHILDREN(bbr_hptsi), 1292 OID_AUTO, "enet_oh", CTLFLAG_RW, 1293 &bbr_include_enet_oh, 0, 1294 "Do we include the ethernet overhead in calculating pacing delay?"); 1295 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1296 SYSCTL_CHILDREN(bbr_hptsi), 1297 OID_AUTO, "ip_oh", CTLFLAG_RW, 1298 &bbr_include_ip_oh, 1, 1299 "Do we include the IP overhead in calculating pacing delay?"); 1300 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1301 SYSCTL_CHILDREN(bbr_hptsi), 1302 OID_AUTO, "tcp_oh", CTLFLAG_RW, 1303 &bbr_include_tcp_oh, 0, 1304 "Do we include the TCP overhead in calculating pacing delay?"); 1305 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1306 SYSCTL_CHILDREN(bbr_hptsi), 1307 OID_AUTO, "google_discount", CTLFLAG_RW, 1308 &bbr_google_discount, 10, 1309 "What is the default google discount percentage wise for pacing (11 = 1.1%%)?"); 1310 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1311 SYSCTL_CHILDREN(bbr_hptsi), 1312 OID_AUTO, "all_get_min", CTLFLAG_RW, 1313 &bbr_all_get_min, 0, 1314 "If you are less than a MSS do you just get the min?"); 1315 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1316 SYSCTL_CHILDREN(bbr_hptsi), 1317 OID_AUTO, "tso_min", CTLFLAG_RW, 1318 &bbr_hptsi_bytes_min, 1460, 1319 "For 0 -> 24Mbps what is floor number of segments for TSO"); 1320 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1321 SYSCTL_CHILDREN(bbr_hptsi), 1322 OID_AUTO, "seg_tso_max", CTLFLAG_RW, 1323 &bbr_hptsi_segments_max, 6, 1324 "For 0 -> 24Mbps what is top number of segments for TSO"); 1325 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1326 SYSCTL_CHILDREN(bbr_hptsi), 1327 OID_AUTO, "seg_floor", CTLFLAG_RW, 1328 &bbr_hptsi_segments_floor, 1, 1329 "Minimum TSO size we will fall too in segments"); 1330 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1331 SYSCTL_CHILDREN(bbr_hptsi), 1332 OID_AUTO, "utter_max", CTLFLAG_RW, 1333 &bbr_hptsi_utter_max, 0, 1334 "The absolute maximum that any pacing (outside of hardware) can be"); 1335 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1336 SYSCTL_CHILDREN(bbr_hptsi), 1337 OID_AUTO, "seg_divisor", CTLFLAG_RW, 1338 &bbr_hptsi_per_second, 100, 1339 "What is the divisor in our hptsi TSO calculation 512Mbps < X > 24Mbps "); 1340 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1341 SYSCTL_CHILDREN(bbr_hptsi), 1342 OID_AUTO, "srtt_mul", CTLFLAG_RW, 1343 &bbr_hptsi_max_mul, 1, 1344 "The multiplier for pace len max"); 1345 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1346 SYSCTL_CHILDREN(bbr_hptsi), 1347 OID_AUTO, "srtt_div", CTLFLAG_RW, 1348 &bbr_hptsi_max_div, 2, 1349 "The divisor for pace len max"); 1350 /* Measurement controls */ 1351 bbr_measure = SYSCTL_ADD_NODE(&bbr_sysctl_ctx, 1352 SYSCTL_CHILDREN(bbr_sysctl_root), 1353 OID_AUTO, 1354 "measure", 1355 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1356 "Measurement controls"); 1357 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1358 SYSCTL_CHILDREN(bbr_measure), 1359 OID_AUTO, "min_i_bw", CTLFLAG_RW, 1360 &bbr_initial_bw_bps, 62500, 1361 "Minimum initial b/w in bytes per second"); 1362 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1363 SYSCTL_CHILDREN(bbr_measure), 1364 OID_AUTO, "no_sack_needed", CTLFLAG_RW, 1365 &bbr_sack_not_required, 0, 1366 "Do we allow bbr to run on connections not supporting SACK?"); 1367 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1368 SYSCTL_CHILDREN(bbr_measure), 1369 OID_AUTO, "use_google", CTLFLAG_RW, 1370 &bbr_use_google_algo, 0, 1371 "Use has close to google V1.0 has possible?"); 1372 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1373 SYSCTL_CHILDREN(bbr_measure), 1374 OID_AUTO, "ts_limiting", CTLFLAG_RW, 1375 &bbr_ts_limiting, 1, 1376 "Do we attempt to use the peers timestamp to limit b/w caculations?"); 1377 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1378 SYSCTL_CHILDREN(bbr_measure), 1379 OID_AUTO, "ts_can_raise", CTLFLAG_RW, 1380 &bbr_ts_can_raise, 0, 1381 "Can we raise the b/w via timestamp b/w calculation?"); 1382 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1383 SYSCTL_CHILDREN(bbr_measure), 1384 OID_AUTO, "ts_delta", CTLFLAG_RW, 1385 &bbr_min_usec_delta, 20000, 1386 "How long in usec between ts of our sends in ts validation code?"); 1387 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1388 SYSCTL_CHILDREN(bbr_measure), 1389 OID_AUTO, "ts_peer_delta", CTLFLAG_RW, 1390 &bbr_min_peer_delta, 20, 1391 "What min numerical value should be between the peer deltas?"); 1392 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1393 SYSCTL_CHILDREN(bbr_measure), 1394 OID_AUTO, "ts_delta_percent", CTLFLAG_RW, 1395 &bbr_delta_percent, 150, 1396 "What percentage (150 = 15.0) do we allow variance for?"); 1397 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1398 SYSCTL_CHILDREN(bbr_measure), 1399 OID_AUTO, "min_measure_good_bw", CTLFLAG_RW, 1400 &bbr_min_measurements_req, 1, 1401 "What is the minimum measurment count we need before we switch to our b/w estimate"); 1402 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1403 SYSCTL_CHILDREN(bbr_measure), 1404 OID_AUTO, "min_measure_before_pace", CTLFLAG_RW, 1405 &bbr_no_pacing_until, 4, 1406 "How many pkt-epoch's (0 is off) do we need before pacing is on?"); 1407 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1408 SYSCTL_CHILDREN(bbr_measure), 1409 OID_AUTO, "quanta", CTLFLAG_RW, 1410 &bbr_quanta, 2, 1411 "Extra quanta to add when calculating the target (ID section 4.2.3.2)."); 1412 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1413 SYSCTL_CHILDREN(bbr_measure), 1414 OID_AUTO, "noretran", CTLFLAG_RW, 1415 &bbr_no_retran, 0, 1416 "Should google mode not use retransmission measurements for the b/w estimation?"); 1417 /* State controls */ 1418 bbr_states = SYSCTL_ADD_NODE(&bbr_sysctl_ctx, 1419 SYSCTL_CHILDREN(bbr_sysctl_root), 1420 OID_AUTO, 1421 "states", 1422 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1423 "State controls"); 1424 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1425 SYSCTL_CHILDREN(bbr_states), 1426 OID_AUTO, "idle_restart", CTLFLAG_RW, 1427 &bbr_uses_idle_restart, 0, 1428 "Do we use a new special idle_restart state to ramp back up quickly?"); 1429 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1430 SYSCTL_CHILDREN(bbr_states), 1431 OID_AUTO, "idle_restart_threshold", CTLFLAG_RW, 1432 &bbr_idle_restart_threshold, 100000, 1433 "How long must we be idle before we restart??"); 1434 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1435 SYSCTL_CHILDREN(bbr_states), 1436 OID_AUTO, "use_pkt_epoch", CTLFLAG_RW, 1437 &bbr_state_is_pkt_epoch, 0, 1438 "Do we use a pkt-epoch for substate if 0 rttProp?"); 1439 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1440 SYSCTL_CHILDREN(bbr_states), 1441 OID_AUTO, "startup_rtt_gain", CTLFLAG_RW, 1442 &bbr_rtt_gain_thresh, 0, 1443 "What increase in RTT triggers us to stop ignoring no-loss and possibly exit startup?"); 1444 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1445 SYSCTL_CHILDREN(bbr_states), 1446 OID_AUTO, "drain_floor", CTLFLAG_RW, 1447 &bbr_drain_floor, 88, 1448 "What is the lowest we can drain (pg) too?"); 1449 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1450 SYSCTL_CHILDREN(bbr_states), 1451 OID_AUTO, "drain_2_target", CTLFLAG_RW, 1452 &bbr_state_drain_2_tar, 1, 1453 "Do we drain to target in drain substate?"); 1454 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1455 SYSCTL_CHILDREN(bbr_states), 1456 OID_AUTO, "gain_2_target", CTLFLAG_RW, 1457 &bbr_gain_to_target, 1, 1458 "Does probe bw gain to target??"); 1459 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1460 SYSCTL_CHILDREN(bbr_states), 1461 OID_AUTO, "gain_extra_time", CTLFLAG_RW, 1462 &bbr_gain_gets_extra_too, 1, 1463 "Does probe bw gain get the extra time too?"); 1464 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1465 SYSCTL_CHILDREN(bbr_states), 1466 OID_AUTO, "ld_div", CTLFLAG_RW, 1467 &bbr_drain_drop_div, 5, 1468 "Long drain drop divider?"); 1469 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1470 SYSCTL_CHILDREN(bbr_states), 1471 OID_AUTO, "ld_mul", CTLFLAG_RW, 1472 &bbr_drain_drop_mul, 4, 1473 "Long drain drop multiplier?"); 1474 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1475 SYSCTL_CHILDREN(bbr_states), 1476 OID_AUTO, "rand_ot_disc", CTLFLAG_RW, 1477 &bbr_rand_ot, 50, 1478 "Random discount of the ot?"); 1479 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1480 SYSCTL_CHILDREN(bbr_states), 1481 OID_AUTO, "dr_filter_life", CTLFLAG_RW, 1482 &bbr_num_pktepo_for_del_limit, BBR_NUM_RTTS_FOR_DEL_LIMIT, 1483 "How many packet-epochs does the b/w delivery rate last?"); 1484 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1485 SYSCTL_CHILDREN(bbr_states), 1486 OID_AUTO, "subdrain_applimited", CTLFLAG_RW, 1487 &bbr_sub_drain_app_limit, 0, 1488 "Does our sub-state drain invoke app limited if its long?"); 1489 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1490 SYSCTL_CHILDREN(bbr_states), 1491 OID_AUTO, "use_cwnd_subdrain", CTLFLAG_RW, 1492 &bbr_sub_drain_slam_cwnd, 0, 1493 "Should we set/recover cwnd for sub-state drain?"); 1494 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1495 SYSCTL_CHILDREN(bbr_states), 1496 OID_AUTO, "use_cwnd_maindrain", CTLFLAG_RW, 1497 &bbr_slam_cwnd_in_main_drain, 0, 1498 "Should we set/recover cwnd for main-state drain?"); 1499 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1500 SYSCTL_CHILDREN(bbr_states), 1501 OID_AUTO, "google_gets_earlyout", CTLFLAG_RW, 1502 &google_allow_early_out, 1, 1503 "Should we allow google probe-bw/drain to exit early at flight target?"); 1504 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1505 SYSCTL_CHILDREN(bbr_states), 1506 OID_AUTO, "google_exit_loss", CTLFLAG_RW, 1507 &google_consider_lost, 1, 1508 "Should we have losses exit gain of probebw in google mode??"); 1509 /* Startup controls */ 1510 bbr_startup = SYSCTL_ADD_NODE(&bbr_sysctl_ctx, 1511 SYSCTL_CHILDREN(bbr_sysctl_root), 1512 OID_AUTO, 1513 "startup", 1514 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1515 "Startup controls"); 1516 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1517 SYSCTL_CHILDREN(bbr_startup), 1518 OID_AUTO, "cheat_iwnd", CTLFLAG_RW, 1519 &bbr_sends_full_iwnd, 1, 1520 "Do we not pace but burst out initial windows has our TSO size?"); 1521 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1522 SYSCTL_CHILDREN(bbr_startup), 1523 OID_AUTO, "loss_threshold", CTLFLAG_RW, 1524 &bbr_startup_loss_thresh, 2000, 1525 "In startup what is the loss threshold in a pe that will exit us from startup?"); 1526 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1527 SYSCTL_CHILDREN(bbr_startup), 1528 OID_AUTO, "use_lowerpg", CTLFLAG_RW, 1529 &bbr_use_lower_gain_in_startup, 1, 1530 "Should we use a lower hptsi gain if we see loss in startup?"); 1531 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1532 SYSCTL_CHILDREN(bbr_startup), 1533 OID_AUTO, "gain", CTLFLAG_RW, 1534 &bbr_start_exit, 25, 1535 "What gain percent do we need to see to stay in startup??"); 1536 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1537 SYSCTL_CHILDREN(bbr_startup), 1538 OID_AUTO, "low_gain", CTLFLAG_RW, 1539 &bbr_low_start_exit, 15, 1540 "What gain percent do we need to see to stay in the lower gain startup??"); 1541 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1542 SYSCTL_CHILDREN(bbr_startup), 1543 OID_AUTO, "loss_exit", CTLFLAG_RW, 1544 &bbr_exit_startup_at_loss, 1, 1545 "Should we exit startup at loss in an epoch if we are not gaining?"); 1546 /* CWND controls */ 1547 bbr_cwnd = SYSCTL_ADD_NODE(&bbr_sysctl_ctx, 1548 SYSCTL_CHILDREN(bbr_sysctl_root), 1549 OID_AUTO, 1550 "cwnd", 1551 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1552 "Cwnd controls"); 1553 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1554 SYSCTL_CHILDREN(bbr_cwnd), 1555 OID_AUTO, "tar_rtt", CTLFLAG_RW, 1556 &bbr_cwndtarget_rtt_touse, 0, 1557 "Target cwnd rtt measurment to use (0=rtt_prop, 1=rtt_rack, 2=pkt_rtt, 3=srtt)?"); 1558 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1559 SYSCTL_CHILDREN(bbr_cwnd), 1560 OID_AUTO, "may_shrink", CTLFLAG_RW, 1561 &bbr_cwnd_may_shrink, 0, 1562 "Can the cwnd shrink if it would grow to more than the target?"); 1563 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1564 SYSCTL_CHILDREN(bbr_cwnd), 1565 OID_AUTO, "max_target_limit", CTLFLAG_RW, 1566 &bbr_target_cwnd_mult_limit, 8, 1567 "Do we limit the cwnd to some multiple of the cwnd target if cwnd can't shrink 0=no?"); 1568 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1569 SYSCTL_CHILDREN(bbr_cwnd), 1570 OID_AUTO, "highspeed_min", CTLFLAG_RW, 1571 &bbr_cwnd_min_val_hs, BBR_HIGHSPEED_NUM_MSS, 1572 "What is the high-speed min cwnd (rttProp under 1ms)"); 1573 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1574 SYSCTL_CHILDREN(bbr_cwnd), 1575 OID_AUTO, "lowspeed_min", CTLFLAG_RW, 1576 &bbr_cwnd_min_val, BBR_PROBERTT_NUM_MSS, 1577 "What is the min cwnd (rttProp > 1ms)"); 1578 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1579 SYSCTL_CHILDREN(bbr_cwnd), 1580 OID_AUTO, "initwin", CTLFLAG_RW, 1581 &bbr_def_init_win, 10, 1582 "What is the BBR initial window, if 0 use tcp version"); 1583 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1584 SYSCTL_CHILDREN(bbr_cwnd), 1585 OID_AUTO, "do_loss_red", CTLFLAG_RW, 1586 &bbr_do_red, 600, 1587 "Do we reduce the b/w at exit from recovery based on ratio of prop/srtt (800=80.0, 0=off)?"); 1588 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1589 SYSCTL_CHILDREN(bbr_cwnd), 1590 OID_AUTO, "red_scale", CTLFLAG_RW, 1591 &bbr_red_scale, 20000, 1592 "What RTT do we scale with?"); 1593 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1594 SYSCTL_CHILDREN(bbr_cwnd), 1595 OID_AUTO, "red_growslow", CTLFLAG_RW, 1596 &bbr_red_growth_restrict, 1, 1597 "Do we restrict cwnd growth for whats in flight?"); 1598 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1599 SYSCTL_CHILDREN(bbr_cwnd), 1600 OID_AUTO, "red_div", CTLFLAG_RW, 1601 &bbr_red_div, 2, 1602 "If we reduce whats the divisor?"); 1603 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1604 SYSCTL_CHILDREN(bbr_cwnd), 1605 OID_AUTO, "red_mul", CTLFLAG_RW, 1606 &bbr_red_mul, 1, 1607 "If we reduce whats the mulitiplier?"); 1608 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1609 SYSCTL_CHILDREN(bbr_cwnd), 1610 OID_AUTO, "target_is_unit", CTLFLAG_RW, 1611 &bbr_target_is_bbunit, 0, 1612 "Is the state target the pacing_gain or BBR_UNIT?"); 1613 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1614 SYSCTL_CHILDREN(bbr_cwnd), 1615 OID_AUTO, "drop_limit", CTLFLAG_RW, 1616 &bbr_drop_limit, 0, 1617 "Number of segments limit for drop (0=use min_cwnd w/flight)?"); 1618 1619 /* Timeout controls */ 1620 bbr_timeout = SYSCTL_ADD_NODE(&bbr_sysctl_ctx, 1621 SYSCTL_CHILDREN(bbr_sysctl_root), 1622 OID_AUTO, 1623 "timeout", 1624 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1625 "Time out controls"); 1626 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1627 SYSCTL_CHILDREN(bbr_timeout), 1628 OID_AUTO, "delack", CTLFLAG_RW, 1629 &bbr_delack_time, 100000, 1630 "BBR's delayed ack time"); 1631 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1632 SYSCTL_CHILDREN(bbr_timeout), 1633 OID_AUTO, "tlp_uses", CTLFLAG_RW, 1634 &bbr_tlp_type_to_use, 3, 1635 "RTT that TLP uses in its calculations, 0=rttProp, 1=Rack_rtt, 2=pkt_rtt and 3=srtt"); 1636 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1637 SYSCTL_CHILDREN(bbr_timeout), 1638 OID_AUTO, "persmin", CTLFLAG_RW, 1639 &bbr_persist_min, 250000, 1640 "What is the minimum time in microseconds between persists"); 1641 SYSCTL_ADD_U32(&bbr_sysctl_ctx, 1642 SYSCTL_CHILDREN(bbr_timeout), 1643 OID_AUTO, "persmax", CTLFLAG_RW, 1644 &bbr_persist_max, 1000000, 1645 "What is the largest delay in microseconds between persists"); 1646 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1647 SYSCTL_CHILDREN(bbr_timeout), 1648 OID_AUTO, "tlp_minto", CTLFLAG_RW, 1649 &bbr_tlp_min, 10000, 1650 "TLP Min timeout in usecs"); 1651 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1652 SYSCTL_CHILDREN(bbr_timeout), 1653 OID_AUTO, "tlp_dack_time", CTLFLAG_RW, 1654 &bbr_delayed_ack_time, 200000, 1655 "TLP delayed ack compensation value"); 1656 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1657 SYSCTL_CHILDREN(bbr_sysctl_root), 1658 OID_AUTO, "minrto", CTLFLAG_RW, 1659 &bbr_rto_min_ms, 30, 1660 "Minimum RTO in ms"); 1661 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1662 SYSCTL_CHILDREN(bbr_timeout), 1663 OID_AUTO, "maxrto", CTLFLAG_RW, 1664 &bbr_rto_max_sec, 4, 1665 "Maxiumum RTO in seconds -- should be at least as large as min_rto"); 1666 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1667 SYSCTL_CHILDREN(bbr_timeout), 1668 OID_AUTO, "tlp_retry", CTLFLAG_RW, 1669 &bbr_tlp_max_resend, 2, 1670 "How many times does TLP retry a single segment or multiple with no ACK"); 1671 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1672 SYSCTL_CHILDREN(bbr_timeout), 1673 OID_AUTO, "minto", CTLFLAG_RW, 1674 &bbr_min_to, 1000, 1675 "Minimum rack timeout in useconds"); 1676 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1677 SYSCTL_CHILDREN(bbr_timeout), 1678 OID_AUTO, "pktdelay", CTLFLAG_RW, 1679 &bbr_pkt_delay, 1000, 1680 "Extra RACK time (in useconds) besides reordering thresh"); 1681 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1682 SYSCTL_CHILDREN(bbr_timeout), 1683 OID_AUTO, "incr_tmrs", CTLFLAG_RW, 1684 &bbr_incr_timers, 1, 1685 "Increase the RXT/TLP timer by the pacing time used?"); 1686 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1687 SYSCTL_CHILDREN(bbr_timeout), 1688 OID_AUTO, "rxtmark_sackpassed", CTLFLAG_RW, 1689 &bbr_marks_rxt_sack_passed, 0, 1690 "Mark sack passed on all those not ack'd when a RXT hits?"); 1691 /* Policer controls */ 1692 bbr_policer = SYSCTL_ADD_NODE(&bbr_sysctl_ctx, 1693 SYSCTL_CHILDREN(bbr_sysctl_root), 1694 OID_AUTO, 1695 "policer", 1696 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1697 "Policer controls"); 1698 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1699 SYSCTL_CHILDREN(bbr_policer), 1700 OID_AUTO, "detect_enable", CTLFLAG_RW, 1701 &bbr_policer_detection_enabled, 1, 1702 "Is policer detection enabled??"); 1703 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1704 SYSCTL_CHILDREN(bbr_policer), 1705 OID_AUTO, "min_pes", CTLFLAG_RW, 1706 &bbr_lt_intvl_min_rtts, 4, 1707 "Minimum number of PE's?"); 1708 SYSCTL_ADD_U64(&bbr_sysctl_ctx, 1709 SYSCTL_CHILDREN(bbr_policer), 1710 OID_AUTO, "bwdiff", CTLFLAG_RW, 1711 &bbr_lt_bw_diff, (4000/8), 1712 "Minimal bw diff?"); 1713 SYSCTL_ADD_U64(&bbr_sysctl_ctx, 1714 SYSCTL_CHILDREN(bbr_policer), 1715 OID_AUTO, "bwratio", CTLFLAG_RW, 1716 &bbr_lt_bw_ratio, 8, 1717 "Minimal bw diff?"); 1718 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1719 SYSCTL_CHILDREN(bbr_policer), 1720 OID_AUTO, "from_rack_rxt", CTLFLAG_RW, 1721 &bbr_policer_call_from_rack_to, 0, 1722 "Do we call the policer detection code from a rack-timeout?"); 1723 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1724 SYSCTL_CHILDREN(bbr_policer), 1725 OID_AUTO, "false_postive", CTLFLAG_RW, 1726 &bbr_lt_intvl_fp, 0, 1727 "What packet epoch do we do false-postive detection at (0=no)?"); 1728 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1729 SYSCTL_CHILDREN(bbr_policer), 1730 OID_AUTO, "loss_thresh", CTLFLAG_RW, 1731 &bbr_lt_loss_thresh, 196, 1732 "Loss threshold 196 = 19.6%?"); 1733 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1734 SYSCTL_CHILDREN(bbr_policer), 1735 OID_AUTO, "false_postive_thresh", CTLFLAG_RW, 1736 &bbr_lt_fd_thresh, 100, 1737 "What percentage is the false detection threshold (150=15.0)?"); 1738 /* All the rest */ 1739 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1740 SYSCTL_CHILDREN(bbr_sysctl_root), 1741 OID_AUTO, "cheat_rxt", CTLFLAG_RW, 1742 &bbr_use_rack_resend_cheat, 0, 1743 "Do we burst 1ms between sends on retransmissions (like rack)?"); 1744 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1745 SYSCTL_CHILDREN(bbr_sysctl_root), 1746 OID_AUTO, "error_paceout", CTLFLAG_RW, 1747 &bbr_error_base_paceout, 10000, 1748 "When we hit an error what is the min to pace out in usec's?"); 1749 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1750 SYSCTL_CHILDREN(bbr_sysctl_root), 1751 OID_AUTO, "kill_paceout", CTLFLAG_RW, 1752 &bbr_max_net_error_cnt, 10, 1753 "When we hit this many errors in a row, kill the session?"); 1754 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1755 SYSCTL_CHILDREN(bbr_sysctl_root), 1756 OID_AUTO, "data_after_close", CTLFLAG_RW, 1757 &bbr_ignore_data_after_close, 1, 1758 "Do we hold off sending a RST until all pending data is ack'd"); 1759 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1760 SYSCTL_CHILDREN(bbr_sysctl_root), 1761 OID_AUTO, "resend_use_tso", CTLFLAG_RW, 1762 &bbr_resends_use_tso, 0, 1763 "Can resends use TSO?"); 1764 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1765 SYSCTL_CHILDREN(bbr_sysctl_root), 1766 OID_AUTO, "sblklimit", CTLFLAG_RW, 1767 &bbr_sack_block_limit, 128, 1768 "When do we start ignoring small sack blocks"); 1769 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1770 SYSCTL_CHILDREN(bbr_sysctl_root), 1771 OID_AUTO, "bb_verbose", CTLFLAG_RW, 1772 &bbr_verbose_logging, 0, 1773 "Should BBR black box logging be verbose"); 1774 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1775 SYSCTL_CHILDREN(bbr_sysctl_root), 1776 OID_AUTO, "reorder_thresh", CTLFLAG_RW, 1777 &bbr_reorder_thresh, 2, 1778 "What factor for rack will be added when seeing reordering (shift right)"); 1779 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1780 SYSCTL_CHILDREN(bbr_sysctl_root), 1781 OID_AUTO, "reorder_fade", CTLFLAG_RW, 1782 &bbr_reorder_fade, 0, 1783 "Does reorder detection fade, if so how many ms (0 means never)"); 1784 SYSCTL_ADD_S32(&bbr_sysctl_ctx, 1785 SYSCTL_CHILDREN(bbr_sysctl_root), 1786 OID_AUTO, "rtt_tlp_thresh", CTLFLAG_RW, 1787 &bbr_tlp_thresh, 1, 1788 "what divisor for TLP rtt/retran will be added (1=rtt, 2=1/2 rtt etc)"); 1789 /* Stats and counters */ 1790 /* The pacing counters for hdwr/software can't be in the array */ 1791 bbr_nohdwr_pacing_enobuf = counter_u64_alloc(M_WAITOK); 1792 bbr_hdwr_pacing_enobuf = counter_u64_alloc(M_WAITOK); 1793 SYSCTL_ADD_COUNTER_U64(&bbr_sysctl_ctx, 1794 SYSCTL_CHILDREN(bbr_sysctl_root), 1795 OID_AUTO, "enob_hdwr_pacing", CTLFLAG_RD, 1796 &bbr_hdwr_pacing_enobuf, 1797 "Total number of enobufs for hardware paced flows"); 1798 SYSCTL_ADD_COUNTER_U64(&bbr_sysctl_ctx, 1799 SYSCTL_CHILDREN(bbr_sysctl_root), 1800 OID_AUTO, "enob_no_hdwr_pacing", CTLFLAG_RD, 1801 &bbr_nohdwr_pacing_enobuf, 1802 "Total number of enobufs for non-hardware paced flows"); 1803 1804 bbr_flows_whdwr_pacing = counter_u64_alloc(M_WAITOK); 1805 SYSCTL_ADD_COUNTER_U64(&bbr_sysctl_ctx, 1806 SYSCTL_CHILDREN(bbr_sysctl_root), 1807 OID_AUTO, "hdwr_pacing", CTLFLAG_RD, 1808 &bbr_flows_whdwr_pacing, 1809 "Total number of hardware paced flows"); 1810 bbr_flows_nohdwr_pacing = counter_u64_alloc(M_WAITOK); 1811 SYSCTL_ADD_COUNTER_U64(&bbr_sysctl_ctx, 1812 SYSCTL_CHILDREN(bbr_sysctl_root), 1813 OID_AUTO, "software_pacing", CTLFLAG_RD, 1814 &bbr_flows_nohdwr_pacing, 1815 "Total number of software paced flows"); 1816 COUNTER_ARRAY_ALLOC(bbr_stat_arry, BBR_STAT_SIZE, M_WAITOK); 1817 SYSCTL_ADD_COUNTER_U64_ARRAY(&bbr_sysctl_ctx, SYSCTL_CHILDREN(bbr_sysctl_root), 1818 OID_AUTO, "stats", CTLFLAG_RD, 1819 bbr_stat_arry, BBR_STAT_SIZE, "BBR Stats"); 1820 COUNTER_ARRAY_ALLOC(bbr_opts_arry, BBR_OPTS_SIZE, M_WAITOK); 1821 SYSCTL_ADD_COUNTER_U64_ARRAY(&bbr_sysctl_ctx, SYSCTL_CHILDREN(bbr_sysctl_root), 1822 OID_AUTO, "opts", CTLFLAG_RD, 1823 bbr_opts_arry, BBR_OPTS_SIZE, "BBR Option Stats"); 1824 COUNTER_ARRAY_ALLOC(bbr_state_lost, BBR_MAX_STAT, M_WAITOK); 1825 SYSCTL_ADD_COUNTER_U64_ARRAY(&bbr_sysctl_ctx, SYSCTL_CHILDREN(bbr_sysctl_root), 1826 OID_AUTO, "lost", CTLFLAG_RD, 1827 bbr_state_lost, BBR_MAX_STAT, "Stats of when losses occur"); 1828 COUNTER_ARRAY_ALLOC(bbr_state_resend, BBR_MAX_STAT, M_WAITOK); 1829 SYSCTL_ADD_COUNTER_U64_ARRAY(&bbr_sysctl_ctx, SYSCTL_CHILDREN(bbr_sysctl_root), 1830 OID_AUTO, "stateresend", CTLFLAG_RD, 1831 bbr_state_resend, BBR_MAX_STAT, "Stats of what states resend"); 1832 COUNTER_ARRAY_ALLOC(bbr_state_time, BBR_MAX_STAT, M_WAITOK); 1833 SYSCTL_ADD_COUNTER_U64_ARRAY(&bbr_sysctl_ctx, SYSCTL_CHILDREN(bbr_sysctl_root), 1834 OID_AUTO, "statetime", CTLFLAG_RD, 1835 bbr_state_time, BBR_MAX_STAT, "Stats of time spent in the states"); 1836 COUNTER_ARRAY_ALLOC(bbr_out_size, TCP_MSS_ACCT_SIZE, M_WAITOK); 1837 SYSCTL_ADD_COUNTER_U64_ARRAY(&bbr_sysctl_ctx, SYSCTL_CHILDREN(bbr_sysctl_root), 1838 OID_AUTO, "outsize", CTLFLAG_RD, 1839 bbr_out_size, TCP_MSS_ACCT_SIZE, "Size of output calls"); 1840 SYSCTL_ADD_PROC(&bbr_sysctl_ctx, 1841 SYSCTL_CHILDREN(bbr_sysctl_root), 1842 OID_AUTO, "clrlost", CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_MPSAFE, 1843 &bbr_clear_lost, 0, sysctl_bbr_clear_lost, "IU", "Clear lost counters"); 1844 } 1845 1846 static void 1847 bbr_counter_destroy(void) 1848 { 1849 COUNTER_ARRAY_FREE(bbr_stat_arry, BBR_STAT_SIZE); 1850 COUNTER_ARRAY_FREE(bbr_opts_arry, BBR_OPTS_SIZE); 1851 COUNTER_ARRAY_FREE(bbr_out_size, TCP_MSS_ACCT_SIZE); 1852 COUNTER_ARRAY_FREE(bbr_state_lost, BBR_MAX_STAT); 1853 COUNTER_ARRAY_FREE(bbr_state_time, BBR_MAX_STAT); 1854 COUNTER_ARRAY_FREE(bbr_state_resend, BBR_MAX_STAT); 1855 counter_u64_free(bbr_nohdwr_pacing_enobuf); 1856 counter_u64_free(bbr_hdwr_pacing_enobuf); 1857 counter_u64_free(bbr_flows_whdwr_pacing); 1858 counter_u64_free(bbr_flows_nohdwr_pacing); 1859 1860 } 1861 1862 static __inline void 1863 bbr_fill_in_logging_data(struct tcp_bbr *bbr, struct tcp_log_bbr *l, uint32_t cts) 1864 { 1865 memset(l, 0, sizeof(union tcp_log_stackspecific)); 1866 l->cur_del_rate = bbr->r_ctl.rc_bbr_cur_del_rate; 1867 l->delRate = get_filter_value(&bbr->r_ctl.rc_delrate); 1868 l->rttProp = get_filter_value_small(&bbr->r_ctl.rc_rttprop); 1869 l->bw_inuse = bbr_get_bw(bbr); 1870 l->inflight = ctf_flight_size(bbr->rc_tp, 1871 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 1872 l->applimited = bbr->r_ctl.r_app_limited_until; 1873 l->delivered = bbr->r_ctl.rc_delivered; 1874 l->timeStamp = cts; 1875 l->lost = bbr->r_ctl.rc_lost; 1876 l->bbr_state = bbr->rc_bbr_state; 1877 l->bbr_substate = bbr_state_val(bbr); 1878 l->epoch = bbr->r_ctl.rc_rtt_epoch; 1879 l->lt_epoch = bbr->r_ctl.rc_lt_epoch; 1880 l->pacing_gain = bbr->r_ctl.rc_bbr_hptsi_gain; 1881 l->cwnd_gain = bbr->r_ctl.rc_bbr_cwnd_gain; 1882 l->inhpts = bbr->rc_inp->inp_in_hpts; 1883 l->ininput = bbr->rc_inp->inp_in_input; 1884 l->use_lt_bw = bbr->rc_lt_use_bw; 1885 l->pkts_out = bbr->r_ctl.rc_flight_at_input; 1886 l->pkt_epoch = bbr->r_ctl.rc_pkt_epoch; 1887 } 1888 1889 static void 1890 bbr_log_type_bw_reduce(struct tcp_bbr *bbr, int reason) 1891 { 1892 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 1893 union tcp_log_stackspecific log; 1894 1895 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime); 1896 log.u_bbr.flex1 = 0; 1897 log.u_bbr.flex2 = 0; 1898 log.u_bbr.flex5 = 0; 1899 log.u_bbr.flex3 = 0; 1900 log.u_bbr.flex4 = bbr->r_ctl.rc_pkt_epoch_loss_rate; 1901 log.u_bbr.flex7 = reason; 1902 log.u_bbr.flex6 = bbr->r_ctl.rc_bbr_enters_probertt; 1903 log.u_bbr.flex8 = 0; 1904 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 1905 &bbr->rc_inp->inp_socket->so_rcv, 1906 &bbr->rc_inp->inp_socket->so_snd, 1907 BBR_LOG_BW_RED_EV, 0, 1908 0, &log, false, &bbr->rc_tv); 1909 } 1910 } 1911 1912 static void 1913 bbr_log_type_rwnd_collapse(struct tcp_bbr *bbr, int seq, int mode, uint32_t count) 1914 { 1915 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 1916 union tcp_log_stackspecific log; 1917 1918 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime); 1919 log.u_bbr.flex1 = seq; 1920 log.u_bbr.flex2 = count; 1921 log.u_bbr.flex8 = mode; 1922 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 1923 &bbr->rc_inp->inp_socket->so_rcv, 1924 &bbr->rc_inp->inp_socket->so_snd, 1925 BBR_LOG_LOWGAIN, 0, 1926 0, &log, false, &bbr->rc_tv); 1927 } 1928 } 1929 1930 static void 1931 bbr_log_type_just_return(struct tcp_bbr *bbr, uint32_t cts, uint32_t tlen, uint8_t hpts_calling, 1932 uint8_t reason, uint32_t p_maxseg, int len) 1933 { 1934 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 1935 union tcp_log_stackspecific log; 1936 1937 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 1938 log.u_bbr.flex1 = p_maxseg; 1939 log.u_bbr.flex2 = bbr->r_ctl.rc_hpts_flags; 1940 log.u_bbr.flex3 = bbr->r_ctl.rc_timer_exp; 1941 log.u_bbr.flex4 = reason; 1942 log.u_bbr.flex5 = bbr->rc_in_persist; 1943 log.u_bbr.flex6 = bbr->r_ctl.rc_last_delay_val; 1944 log.u_bbr.flex7 = p_maxseg; 1945 log.u_bbr.flex8 = bbr->rc_in_persist; 1946 log.u_bbr.pkts_out = 0; 1947 log.u_bbr.applimited = len; 1948 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 1949 &bbr->rc_inp->inp_socket->so_rcv, 1950 &bbr->rc_inp->inp_socket->so_snd, 1951 BBR_LOG_JUSTRET, 0, 1952 tlen, &log, false, &bbr->rc_tv); 1953 } 1954 } 1955 1956 static void 1957 bbr_log_type_enter_rec(struct tcp_bbr *bbr, uint32_t seq) 1958 { 1959 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 1960 union tcp_log_stackspecific log; 1961 1962 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime); 1963 log.u_bbr.flex1 = seq; 1964 log.u_bbr.flex2 = bbr->r_ctl.rc_cwnd_on_ent; 1965 log.u_bbr.flex3 = bbr->r_ctl.rc_recovery_start; 1966 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 1967 &bbr->rc_inp->inp_socket->so_rcv, 1968 &bbr->rc_inp->inp_socket->so_snd, 1969 BBR_LOG_ENTREC, 0, 1970 0, &log, false, &bbr->rc_tv); 1971 } 1972 } 1973 1974 static void 1975 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) 1976 { 1977 if (tp->t_logstate != TCP_LOG_STATE_OFF) { 1978 union tcp_log_stackspecific log; 1979 1980 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 1981 log.u_bbr.flex1 = tso; 1982 log.u_bbr.flex2 = maxseg; 1983 log.u_bbr.flex3 = mtu; 1984 log.u_bbr.flex4 = csum_flags; 1985 TCP_LOG_EVENTP(tp, NULL, 1986 &bbr->rc_inp->inp_socket->so_rcv, 1987 &bbr->rc_inp->inp_socket->so_snd, 1988 BBR_LOG_MSGSIZE, 0, 1989 0, &log, false, &bbr->rc_tv); 1990 } 1991 } 1992 1993 static void 1994 bbr_log_flowend(struct tcp_bbr *bbr) 1995 { 1996 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 1997 union tcp_log_stackspecific log; 1998 struct sockbuf *r, *s; 1999 struct timeval tv; 2000 2001 if (bbr->rc_inp->inp_socket) { 2002 r = &bbr->rc_inp->inp_socket->so_rcv; 2003 s = &bbr->rc_inp->inp_socket->so_snd; 2004 } else { 2005 r = s = NULL; 2006 } 2007 bbr_fill_in_logging_data(bbr, &log.u_bbr, tcp_get_usecs(&tv)); 2008 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2009 r, s, 2010 TCP_LOG_FLOWEND, 0, 2011 0, &log, false, &tv); 2012 } 2013 } 2014 2015 static void 2016 bbr_log_pkt_epoch(struct tcp_bbr *bbr, uint32_t cts, uint32_t line, 2017 uint32_t lost, uint32_t del) 2018 { 2019 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2020 union tcp_log_stackspecific log; 2021 2022 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2023 log.u_bbr.flex1 = lost; 2024 log.u_bbr.flex2 = del; 2025 log.u_bbr.flex3 = bbr->r_ctl.rc_bbr_lastbtlbw; 2026 log.u_bbr.flex4 = bbr->r_ctl.rc_pkt_epoch_rtt; 2027 log.u_bbr.flex5 = bbr->r_ctl.rc_bbr_last_startup_epoch; 2028 log.u_bbr.flex6 = bbr->r_ctl.rc_lost_at_startup; 2029 log.u_bbr.flex7 = line; 2030 log.u_bbr.flex8 = 0; 2031 log.u_bbr.inflight = bbr->r_ctl.r_measurement_count; 2032 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2033 &bbr->rc_inp->inp_socket->so_rcv, 2034 &bbr->rc_inp->inp_socket->so_snd, 2035 BBR_LOG_PKT_EPOCH, 0, 2036 0, &log, false, &bbr->rc_tv); 2037 } 2038 } 2039 2040 static void 2041 bbr_log_time_epoch(struct tcp_bbr *bbr, uint32_t cts, uint32_t line, uint32_t epoch_time) 2042 { 2043 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) { 2044 union tcp_log_stackspecific log; 2045 2046 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2047 log.u_bbr.flex1 = bbr->r_ctl.rc_lost; 2048 log.u_bbr.flex2 = bbr->rc_inp->inp_socket->so_snd.sb_lowat; 2049 log.u_bbr.flex3 = bbr->rc_inp->inp_socket->so_snd.sb_hiwat; 2050 log.u_bbr.flex7 = line; 2051 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2052 &bbr->rc_inp->inp_socket->so_rcv, 2053 &bbr->rc_inp->inp_socket->so_snd, 2054 BBR_LOG_TIME_EPOCH, 0, 2055 0, &log, false, &bbr->rc_tv); 2056 } 2057 } 2058 2059 static void 2060 bbr_log_set_of_state_target(struct tcp_bbr *bbr, uint32_t new_tar, int line, int meth) 2061 { 2062 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2063 union tcp_log_stackspecific log; 2064 2065 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime); 2066 log.u_bbr.flex1 = bbr->r_ctl.rc_target_at_state; 2067 log.u_bbr.flex2 = new_tar; 2068 log.u_bbr.flex3 = line; 2069 log.u_bbr.flex4 = bbr->r_ctl.rc_pace_max_segs; 2070 log.u_bbr.flex5 = bbr_quanta; 2071 log.u_bbr.flex6 = bbr->r_ctl.rc_pace_min_segs; 2072 log.u_bbr.flex7 = bbr->rc_last_options; 2073 log.u_bbr.flex8 = meth; 2074 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2075 &bbr->rc_inp->inp_socket->so_rcv, 2076 &bbr->rc_inp->inp_socket->so_snd, 2077 BBR_LOG_STATE_TARGET, 0, 2078 0, &log, false, &bbr->rc_tv); 2079 } 2080 2081 } 2082 2083 static void 2084 bbr_log_type_statechange(struct tcp_bbr *bbr, uint32_t cts, int32_t line) 2085 { 2086 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2087 union tcp_log_stackspecific log; 2088 2089 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2090 log.u_bbr.flex1 = line; 2091 log.u_bbr.flex2 = bbr->r_ctl.rc_rtt_shrinks; 2092 log.u_bbr.flex3 = bbr->r_ctl.rc_probertt_int; 2093 if (bbr_state_is_pkt_epoch) 2094 log.u_bbr.flex4 = bbr_get_rtt(bbr, BBR_RTT_PKTRTT); 2095 else 2096 log.u_bbr.flex4 = bbr_get_rtt(bbr, BBR_RTT_PROP); 2097 log.u_bbr.flex5 = bbr->r_ctl.rc_bbr_last_startup_epoch; 2098 log.u_bbr.flex6 = bbr->r_ctl.rc_lost_at_startup; 2099 log.u_bbr.flex7 = (bbr->r_ctl.rc_target_at_state/1000); 2100 log.u_bbr.lt_epoch = bbr->r_ctl.rc_level_state_extra; 2101 log.u_bbr.pkts_out = bbr->r_ctl.rc_target_at_state; 2102 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2103 &bbr->rc_inp->inp_socket->so_rcv, 2104 &bbr->rc_inp->inp_socket->so_snd, 2105 BBR_LOG_STATE, 0, 2106 0, &log, false, &bbr->rc_tv); 2107 } 2108 } 2109 2110 static void 2111 bbr_log_rtt_shrinks(struct tcp_bbr *bbr, uint32_t cts, uint32_t applied, 2112 uint32_t rtt, uint32_t line, uint8_t reas, uint16_t cond) 2113 { 2114 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2115 union tcp_log_stackspecific log; 2116 2117 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2118 log.u_bbr.flex1 = line; 2119 log.u_bbr.flex2 = bbr->r_ctl.rc_rtt_shrinks; 2120 log.u_bbr.flex3 = bbr->r_ctl.last_in_probertt; 2121 log.u_bbr.flex4 = applied; 2122 log.u_bbr.flex5 = rtt; 2123 log.u_bbr.flex6 = bbr->r_ctl.rc_target_at_state; 2124 log.u_bbr.flex7 = cond; 2125 log.u_bbr.flex8 = reas; 2126 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2127 &bbr->rc_inp->inp_socket->so_rcv, 2128 &bbr->rc_inp->inp_socket->so_snd, 2129 BBR_LOG_RTT_SHRINKS, 0, 2130 0, &log, false, &bbr->rc_tv); 2131 } 2132 } 2133 2134 static void 2135 bbr_log_type_exit_rec(struct tcp_bbr *bbr) 2136 { 2137 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2138 union tcp_log_stackspecific log; 2139 2140 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime); 2141 log.u_bbr.flex1 = bbr->r_ctl.rc_recovery_start; 2142 log.u_bbr.flex2 = bbr->r_ctl.rc_cwnd_on_ent; 2143 log.u_bbr.flex5 = bbr->r_ctl.rc_target_at_state; 2144 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2145 &bbr->rc_inp->inp_socket->so_rcv, 2146 &bbr->rc_inp->inp_socket->so_snd, 2147 BBR_LOG_EXITREC, 0, 2148 0, &log, false, &bbr->rc_tv); 2149 } 2150 } 2151 2152 static void 2153 bbr_log_type_cwndupd(struct tcp_bbr *bbr, uint32_t bytes_this_ack, uint32_t chg, 2154 uint32_t prev_acked, int32_t meth, uint32_t target, uint32_t th_ack, int32_t line) 2155 { 2156 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) { 2157 union tcp_log_stackspecific log; 2158 2159 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime); 2160 log.u_bbr.flex1 = line; 2161 log.u_bbr.flex2 = prev_acked; 2162 log.u_bbr.flex3 = bytes_this_ack; 2163 log.u_bbr.flex4 = chg; 2164 log.u_bbr.flex5 = th_ack; 2165 log.u_bbr.flex6 = target; 2166 log.u_bbr.flex8 = meth; 2167 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2168 &bbr->rc_inp->inp_socket->so_rcv, 2169 &bbr->rc_inp->inp_socket->so_snd, 2170 BBR_LOG_CWND, 0, 2171 0, &log, false, &bbr->rc_tv); 2172 } 2173 } 2174 2175 static void 2176 bbr_log_rtt_sample(struct tcp_bbr *bbr, uint32_t rtt, uint32_t tsin) 2177 { 2178 /* 2179 * Log the rtt sample we are applying to the srtt algorithm in 2180 * useconds. 2181 */ 2182 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2183 union tcp_log_stackspecific log; 2184 2185 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime); 2186 log.u_bbr.flex1 = rtt; 2187 log.u_bbr.flex2 = bbr->r_ctl.rc_bbr_state_time; 2188 log.u_bbr.flex3 = bbr->r_ctl.rc_ack_hdwr_delay; 2189 log.u_bbr.flex4 = bbr->rc_tp->ts_offset; 2190 log.u_bbr.flex5 = bbr->r_ctl.rc_target_at_state; 2191 log.u_bbr.pkts_out = tcp_tv_to_mssectick(&bbr->rc_tv); 2192 log.u_bbr.flex6 = tsin; 2193 log.u_bbr.flex7 = 0; 2194 log.u_bbr.flex8 = bbr->rc_ack_was_delayed; 2195 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2196 &bbr->rc_inp->inp_socket->so_rcv, 2197 &bbr->rc_inp->inp_socket->so_snd, 2198 TCP_LOG_RTT, 0, 2199 0, &log, false, &bbr->rc_tv); 2200 } 2201 } 2202 2203 static void 2204 bbr_log_type_pesist(struct tcp_bbr *bbr, uint32_t cts, uint32_t time_in, int32_t line, uint8_t enter_exit) 2205 { 2206 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) { 2207 union tcp_log_stackspecific log; 2208 2209 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2210 log.u_bbr.flex1 = time_in; 2211 log.u_bbr.flex2 = line; 2212 log.u_bbr.flex8 = enter_exit; 2213 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2214 &bbr->rc_inp->inp_socket->so_rcv, 2215 &bbr->rc_inp->inp_socket->so_snd, 2216 BBR_LOG_PERSIST, 0, 2217 0, &log, false, &bbr->rc_tv); 2218 } 2219 } 2220 static void 2221 bbr_log_ack_clear(struct tcp_bbr *bbr, uint32_t cts) 2222 { 2223 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) { 2224 union tcp_log_stackspecific log; 2225 2226 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2227 log.u_bbr.flex1 = bbr->rc_tp->ts_recent_age; 2228 log.u_bbr.flex2 = bbr->r_ctl.rc_rtt_shrinks; 2229 log.u_bbr.flex3 = bbr->r_ctl.rc_probertt_int; 2230 log.u_bbr.flex4 = bbr->r_ctl.rc_went_idle_time; 2231 log.u_bbr.flex5 = bbr->r_ctl.rc_target_at_state; 2232 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2233 &bbr->rc_inp->inp_socket->so_rcv, 2234 &bbr->rc_inp->inp_socket->so_snd, 2235 BBR_LOG_ACKCLEAR, 0, 2236 0, &log, false, &bbr->rc_tv); 2237 } 2238 } 2239 2240 static void 2241 bbr_log_ack_event(struct tcp_bbr *bbr, struct tcphdr *th, struct tcpopt *to, uint32_t tlen, 2242 uint16_t nsegs, uint32_t cts, int32_t nxt_pkt, struct mbuf *m) 2243 { 2244 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2245 union tcp_log_stackspecific log; 2246 struct timeval tv; 2247 2248 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2249 log.u_bbr.flex1 = nsegs; 2250 log.u_bbr.flex2 = bbr->r_ctl.rc_lost_bytes; 2251 if (m) { 2252 struct timespec ts; 2253 2254 log.u_bbr.flex3 = m->m_flags; 2255 if (m->m_flags & M_TSTMP) { 2256 mbuf_tstmp2timespec(m, &ts); 2257 tv.tv_sec = ts.tv_sec; 2258 tv.tv_usec = ts.tv_nsec / 1000; 2259 log.u_bbr.lt_epoch = tcp_tv_to_usectick(&tv); 2260 } else { 2261 log.u_bbr.lt_epoch = 0; 2262 } 2263 if (m->m_flags & M_TSTMP_LRO) { 2264 tv.tv_sec = m->m_pkthdr.rcv_tstmp / 1000000000; 2265 tv.tv_usec = (m->m_pkthdr.rcv_tstmp % 1000000000) / 1000; 2266 log.u_bbr.flex5 = tcp_tv_to_usectick(&tv); 2267 } else { 2268 /* No arrival timestamp */ 2269 log.u_bbr.flex5 = 0; 2270 } 2271 2272 log.u_bbr.pkts_out = tcp_get_usecs(&tv); 2273 } else { 2274 log.u_bbr.flex3 = 0; 2275 log.u_bbr.flex5 = 0; 2276 log.u_bbr.flex6 = 0; 2277 log.u_bbr.pkts_out = 0; 2278 } 2279 log.u_bbr.flex4 = bbr->r_ctl.rc_target_at_state; 2280 log.u_bbr.flex7 = bbr->r_wanted_output; 2281 log.u_bbr.flex8 = bbr->rc_in_persist; 2282 TCP_LOG_EVENTP(bbr->rc_tp, th, 2283 &bbr->rc_inp->inp_socket->so_rcv, 2284 &bbr->rc_inp->inp_socket->so_snd, 2285 TCP_LOG_IN, 0, 2286 tlen, &log, true, &bbr->rc_tv); 2287 } 2288 } 2289 2290 static void 2291 bbr_log_doseg_done(struct tcp_bbr *bbr, uint32_t cts, int32_t nxt_pkt, int32_t did_out) 2292 { 2293 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2294 union tcp_log_stackspecific log; 2295 2296 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2297 log.u_bbr.flex1 = did_out; 2298 log.u_bbr.flex2 = nxt_pkt; 2299 log.u_bbr.flex3 = bbr->r_ctl.rc_last_delay_val; 2300 log.u_bbr.flex4 = bbr->r_ctl.rc_hpts_flags; 2301 log.u_bbr.flex5 = bbr->r_ctl.rc_timer_exp; 2302 log.u_bbr.flex6 = bbr->r_ctl.rc_lost_bytes; 2303 log.u_bbr.flex7 = bbr->r_wanted_output; 2304 log.u_bbr.flex8 = bbr->rc_in_persist; 2305 log.u_bbr.pkts_out = bbr->r_ctl.highest_hdwr_delay; 2306 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2307 &bbr->rc_inp->inp_socket->so_rcv, 2308 &bbr->rc_inp->inp_socket->so_snd, 2309 BBR_LOG_DOSEG_DONE, 0, 2310 0, &log, true, &bbr->rc_tv); 2311 } 2312 } 2313 2314 static void 2315 bbr_log_enobuf_jmp(struct tcp_bbr *bbr, uint32_t len, uint32_t cts, 2316 int32_t line, uint32_t o_len, uint32_t segcnt, uint32_t segsiz) 2317 { 2318 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2319 union tcp_log_stackspecific log; 2320 2321 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2322 log.u_bbr.flex1 = line; 2323 log.u_bbr.flex2 = o_len; 2324 log.u_bbr.flex3 = segcnt; 2325 log.u_bbr.flex4 = segsiz; 2326 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2327 &bbr->rc_inp->inp_socket->so_rcv, 2328 &bbr->rc_inp->inp_socket->so_snd, 2329 BBR_LOG_ENOBUF_JMP, ENOBUFS, 2330 len, &log, true, &bbr->rc_tv); 2331 } 2332 } 2333 2334 static void 2335 bbr_log_to_processing(struct tcp_bbr *bbr, uint32_t cts, int32_t ret, int32_t timers, uint8_t hpts_calling) 2336 { 2337 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2338 union tcp_log_stackspecific log; 2339 2340 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2341 log.u_bbr.flex1 = timers; 2342 log.u_bbr.flex2 = ret; 2343 log.u_bbr.flex3 = bbr->r_ctl.rc_timer_exp; 2344 log.u_bbr.flex4 = bbr->r_ctl.rc_hpts_flags; 2345 log.u_bbr.flex5 = cts; 2346 log.u_bbr.flex6 = bbr->r_ctl.rc_target_at_state; 2347 log.u_bbr.flex8 = hpts_calling; 2348 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2349 &bbr->rc_inp->inp_socket->so_rcv, 2350 &bbr->rc_inp->inp_socket->so_snd, 2351 BBR_LOG_TO_PROCESS, 0, 2352 0, &log, false, &bbr->rc_tv); 2353 } 2354 } 2355 2356 static void 2357 bbr_log_to_event(struct tcp_bbr *bbr, uint32_t cts, int32_t to_num) 2358 { 2359 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2360 union tcp_log_stackspecific log; 2361 uint64_t ar; 2362 2363 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2364 log.u_bbr.flex1 = bbr->bbr_timer_src; 2365 log.u_bbr.flex2 = 0; 2366 log.u_bbr.flex3 = bbr->r_ctl.rc_hpts_flags; 2367 ar = (uint64_t)(bbr->r_ctl.rc_resend); 2368 ar >>= 32; 2369 ar &= 0x00000000ffffffff; 2370 log.u_bbr.flex4 = (uint32_t)ar; 2371 ar = (uint64_t)bbr->r_ctl.rc_resend; 2372 ar &= 0x00000000ffffffff; 2373 log.u_bbr.flex5 = (uint32_t)ar; 2374 log.u_bbr.flex6 = TICKS_2_USEC(bbr->rc_tp->t_rxtcur); 2375 log.u_bbr.flex8 = to_num; 2376 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2377 &bbr->rc_inp->inp_socket->so_rcv, 2378 &bbr->rc_inp->inp_socket->so_snd, 2379 BBR_LOG_RTO, 0, 2380 0, &log, false, &bbr->rc_tv); 2381 } 2382 } 2383 2384 static void 2385 bbr_log_startup_event(struct tcp_bbr *bbr, uint32_t cts, uint32_t flex1, uint32_t flex2, uint32_t flex3, uint8_t reason) 2386 { 2387 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2388 union tcp_log_stackspecific log; 2389 2390 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2391 log.u_bbr.flex1 = flex1; 2392 log.u_bbr.flex2 = flex2; 2393 log.u_bbr.flex3 = flex3; 2394 log.u_bbr.flex4 = 0; 2395 log.u_bbr.flex5 = bbr->r_ctl.rc_target_at_state; 2396 log.u_bbr.flex6 = bbr->r_ctl.rc_lost_at_startup; 2397 log.u_bbr.flex8 = reason; 2398 log.u_bbr.cur_del_rate = bbr->r_ctl.rc_bbr_lastbtlbw; 2399 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2400 &bbr->rc_inp->inp_socket->so_rcv, 2401 &bbr->rc_inp->inp_socket->so_snd, 2402 BBR_LOG_REDUCE, 0, 2403 0, &log, false, &bbr->rc_tv); 2404 } 2405 } 2406 2407 static void 2408 bbr_log_hpts_diag(struct tcp_bbr *bbr, uint32_t cts, struct hpts_diag *diag) 2409 { 2410 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) { 2411 union tcp_log_stackspecific log; 2412 2413 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2414 log.u_bbr.flex1 = diag->p_nxt_slot; 2415 log.u_bbr.flex2 = diag->p_cur_slot; 2416 log.u_bbr.flex3 = diag->slot_req; 2417 log.u_bbr.flex4 = diag->inp_hptsslot; 2418 log.u_bbr.flex5 = diag->slot_remaining; 2419 log.u_bbr.flex6 = diag->need_new_to; 2420 log.u_bbr.flex7 = diag->p_hpts_active; 2421 log.u_bbr.flex8 = diag->p_on_min_sleep; 2422 /* Hijack other fields as needed */ 2423 log.u_bbr.epoch = diag->have_slept; 2424 log.u_bbr.lt_epoch = diag->yet_to_sleep; 2425 log.u_bbr.pkts_out = diag->co_ret; 2426 log.u_bbr.applimited = diag->hpts_sleep_time; 2427 log.u_bbr.delivered = diag->p_prev_slot; 2428 log.u_bbr.inflight = diag->p_runningtick; 2429 log.u_bbr.bw_inuse = diag->wheel_tick; 2430 log.u_bbr.rttProp = diag->wheel_cts; 2431 log.u_bbr.delRate = diag->maxticks; 2432 log.u_bbr.cur_del_rate = diag->p_curtick; 2433 log.u_bbr.cur_del_rate <<= 32; 2434 log.u_bbr.cur_del_rate |= diag->p_lasttick; 2435 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2436 &bbr->rc_inp->inp_socket->so_rcv, 2437 &bbr->rc_inp->inp_socket->so_snd, 2438 BBR_LOG_HPTSDIAG, 0, 2439 0, &log, false, &bbr->rc_tv); 2440 } 2441 } 2442 2443 static void 2444 bbr_log_timer_var(struct tcp_bbr *bbr, int mode, uint32_t cts, uint32_t time_since_sent, uint32_t srtt, 2445 uint32_t thresh, uint32_t to) 2446 { 2447 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) { 2448 union tcp_log_stackspecific log; 2449 2450 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2451 log.u_bbr.flex1 = bbr->rc_tp->t_rttvar; 2452 log.u_bbr.flex2 = time_since_sent; 2453 log.u_bbr.flex3 = srtt; 2454 log.u_bbr.flex4 = thresh; 2455 log.u_bbr.flex5 = to; 2456 log.u_bbr.flex6 = bbr->rc_tp->t_srtt; 2457 log.u_bbr.flex8 = mode; 2458 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2459 &bbr->rc_inp->inp_socket->so_rcv, 2460 &bbr->rc_inp->inp_socket->so_snd, 2461 BBR_LOG_TIMERPREP, 0, 2462 0, &log, false, &bbr->rc_tv); 2463 } 2464 } 2465 2466 static void 2467 bbr_log_pacing_delay_calc(struct tcp_bbr *bbr, uint16_t gain, uint32_t len, 2468 uint32_t cts, uint32_t usecs, uint64_t bw, uint32_t override, int mod) 2469 { 2470 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2471 union tcp_log_stackspecific log; 2472 2473 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2474 log.u_bbr.flex1 = usecs; 2475 log.u_bbr.flex2 = len; 2476 log.u_bbr.flex3 = (uint32_t)((bw >> 32) & 0x00000000ffffffff); 2477 log.u_bbr.flex4 = (uint32_t)(bw & 0x00000000ffffffff); 2478 if (override) 2479 log.u_bbr.flex5 = (1 << 2); 2480 else 2481 log.u_bbr.flex5 = 0; 2482 log.u_bbr.flex6 = override; 2483 log.u_bbr.flex7 = gain; 2484 log.u_bbr.flex8 = mod; 2485 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2486 &bbr->rc_inp->inp_socket->so_rcv, 2487 &bbr->rc_inp->inp_socket->so_snd, 2488 BBR_LOG_HPTSI_CALC, 0, 2489 len, &log, false, &bbr->rc_tv); 2490 } 2491 } 2492 2493 static void 2494 bbr_log_to_start(struct tcp_bbr *bbr, uint32_t cts, uint32_t to, int32_t slot, uint8_t which) 2495 { 2496 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2497 union tcp_log_stackspecific log; 2498 2499 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2500 2501 log.u_bbr.flex1 = bbr->bbr_timer_src; 2502 log.u_bbr.flex2 = to; 2503 log.u_bbr.flex3 = bbr->r_ctl.rc_hpts_flags; 2504 log.u_bbr.flex4 = slot; 2505 log.u_bbr.flex5 = bbr->rc_inp->inp_hptsslot; 2506 log.u_bbr.flex6 = TICKS_2_USEC(bbr->rc_tp->t_rxtcur); 2507 log.u_bbr.pkts_out = bbr->rc_inp->inp_flags2; 2508 log.u_bbr.flex8 = which; 2509 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2510 &bbr->rc_inp->inp_socket->so_rcv, 2511 &bbr->rc_inp->inp_socket->so_snd, 2512 BBR_LOG_TIMERSTAR, 0, 2513 0, &log, false, &bbr->rc_tv); 2514 } 2515 } 2516 2517 static void 2518 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) 2519 { 2520 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) { 2521 union tcp_log_stackspecific log; 2522 2523 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2524 log.u_bbr.flex1 = thresh; 2525 log.u_bbr.flex2 = lro; 2526 log.u_bbr.flex3 = bbr->r_ctl.rc_reorder_ts; 2527 log.u_bbr.flex4 = rsm->r_tim_lastsent[(rsm->r_rtr_cnt - 1)]; 2528 log.u_bbr.flex5 = TICKS_2_USEC(bbr->rc_tp->t_rxtcur); 2529 log.u_bbr.flex6 = srtt; 2530 log.u_bbr.flex7 = bbr->r_ctl.rc_reorder_shift; 2531 log.u_bbr.flex8 = frm; 2532 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2533 &bbr->rc_inp->inp_socket->so_rcv, 2534 &bbr->rc_inp->inp_socket->so_snd, 2535 BBR_LOG_THRESH_CALC, 0, 2536 0, &log, false, &bbr->rc_tv); 2537 } 2538 } 2539 2540 static void 2541 bbr_log_to_cancel(struct tcp_bbr *bbr, int32_t line, uint32_t cts, uint8_t hpts_removed) 2542 { 2543 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2544 union tcp_log_stackspecific log; 2545 2546 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2547 log.u_bbr.flex1 = line; 2548 log.u_bbr.flex2 = bbr->bbr_timer_src; 2549 log.u_bbr.flex3 = bbr->r_ctl.rc_hpts_flags; 2550 log.u_bbr.flex4 = bbr->rc_in_persist; 2551 log.u_bbr.flex5 = bbr->r_ctl.rc_target_at_state; 2552 log.u_bbr.flex6 = TICKS_2_USEC(bbr->rc_tp->t_rxtcur); 2553 log.u_bbr.flex8 = hpts_removed; 2554 log.u_bbr.pkts_out = bbr->rc_pacer_started; 2555 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2556 &bbr->rc_inp->inp_socket->so_rcv, 2557 &bbr->rc_inp->inp_socket->so_snd, 2558 BBR_LOG_TIMERCANC, 0, 2559 0, &log, false, &bbr->rc_tv); 2560 } 2561 } 2562 2563 static void 2564 bbr_log_tstmp_validation(struct tcp_bbr *bbr, uint64_t peer_delta, uint64_t delta) 2565 { 2566 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2567 union tcp_log_stackspecific log; 2568 2569 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime); 2570 log.u_bbr.flex1 = bbr->r_ctl.bbr_peer_tsratio; 2571 log.u_bbr.flex2 = (peer_delta >> 32); 2572 log.u_bbr.flex3 = (peer_delta & 0x00000000ffffffff); 2573 log.u_bbr.flex4 = (delta >> 32); 2574 log.u_bbr.flex5 = (delta & 0x00000000ffffffff); 2575 log.u_bbr.flex7 = bbr->rc_ts_clock_set; 2576 log.u_bbr.flex8 = bbr->rc_ts_cant_be_used; 2577 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2578 &bbr->rc_inp->inp_socket->so_rcv, 2579 &bbr->rc_inp->inp_socket->so_snd, 2580 BBR_LOG_TSTMP_VAL, 0, 2581 0, &log, false, &bbr->rc_tv); 2582 } 2583 } 2584 2585 static void 2586 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) 2587 { 2588 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2589 union tcp_log_stackspecific log; 2590 2591 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2592 log.u_bbr.flex1 = tsosz; 2593 log.u_bbr.flex2 = tls; 2594 log.u_bbr.flex3 = tcp_min_hptsi_time; 2595 log.u_bbr.flex4 = bbr->r_ctl.bbr_hptsi_bytes_min; 2596 log.u_bbr.flex5 = old_val; 2597 log.u_bbr.flex6 = maxseg; 2598 log.u_bbr.flex7 = bbr->rc_no_pacing; 2599 log.u_bbr.flex7 <<= 1; 2600 log.u_bbr.flex7 |= bbr->rc_past_init_win; 2601 if (hdwr) 2602 log.u_bbr.flex8 = 0x80 | bbr->rc_use_google; 2603 else 2604 log.u_bbr.flex8 = bbr->rc_use_google; 2605 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2606 &bbr->rc_inp->inp_socket->so_rcv, 2607 &bbr->rc_inp->inp_socket->so_snd, 2608 BBR_LOG_BBRTSO, 0, 2609 0, &log, false, &bbr->rc_tv); 2610 } 2611 } 2612 2613 static void 2614 bbr_log_type_rsmclear(struct tcp_bbr *bbr, uint32_t cts, struct bbr_sendmap *rsm, 2615 uint32_t flags, uint32_t line) 2616 { 2617 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2618 union tcp_log_stackspecific log; 2619 2620 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2621 log.u_bbr.flex1 = line; 2622 log.u_bbr.flex2 = rsm->r_start; 2623 log.u_bbr.flex3 = rsm->r_end; 2624 log.u_bbr.flex4 = rsm->r_delivered; 2625 log.u_bbr.flex5 = rsm->r_rtr_cnt; 2626 log.u_bbr.flex6 = rsm->r_dupack; 2627 log.u_bbr.flex7 = rsm->r_tim_lastsent[0]; 2628 log.u_bbr.flex8 = rsm->r_flags; 2629 /* Hijack the pkts_out fids */ 2630 log.u_bbr.applimited = flags; 2631 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2632 &bbr->rc_inp->inp_socket->so_rcv, 2633 &bbr->rc_inp->inp_socket->so_snd, 2634 BBR_RSM_CLEARED, 0, 2635 0, &log, false, &bbr->rc_tv); 2636 } 2637 } 2638 2639 static void 2640 bbr_log_type_bbrupd(struct tcp_bbr *bbr, uint8_t flex8, uint32_t cts, 2641 uint32_t flex3, uint32_t flex2, uint32_t flex5, 2642 uint32_t flex6, uint32_t pkts_out, int flex7, 2643 uint32_t flex4, uint32_t flex1) 2644 { 2645 2646 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2647 union tcp_log_stackspecific log; 2648 2649 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2650 log.u_bbr.flex1 = flex1; 2651 log.u_bbr.flex2 = flex2; 2652 log.u_bbr.flex3 = flex3; 2653 log.u_bbr.flex4 = flex4; 2654 log.u_bbr.flex5 = flex5; 2655 log.u_bbr.flex6 = flex6; 2656 log.u_bbr.flex7 = flex7; 2657 /* Hijack the pkts_out fids */ 2658 log.u_bbr.pkts_out = pkts_out; 2659 log.u_bbr.flex8 = flex8; 2660 if (bbr->rc_ack_was_delayed) 2661 log.u_bbr.epoch = bbr->r_ctl.rc_ack_hdwr_delay; 2662 else 2663 log.u_bbr.epoch = 0; 2664 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2665 &bbr->rc_inp->inp_socket->so_rcv, 2666 &bbr->rc_inp->inp_socket->so_snd, 2667 BBR_LOG_BBRUPD, 0, 2668 flex2, &log, false, &bbr->rc_tv); 2669 } 2670 } 2671 2672 static void 2673 bbr_log_type_ltbw(struct tcp_bbr *bbr, uint32_t cts, int32_t reason, 2674 uint32_t newbw, uint32_t obw, uint32_t diff, 2675 uint32_t tim) 2676 { 2677 if (/*bbr_verbose_logging && */(bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) { 2678 union tcp_log_stackspecific log; 2679 2680 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2681 log.u_bbr.flex1 = reason; 2682 log.u_bbr.flex2 = newbw; 2683 log.u_bbr.flex3 = obw; 2684 log.u_bbr.flex4 = diff; 2685 log.u_bbr.flex5 = bbr->r_ctl.rc_lt_lost; 2686 log.u_bbr.flex6 = bbr->r_ctl.rc_lt_del; 2687 log.u_bbr.flex7 = bbr->rc_lt_is_sampling; 2688 log.u_bbr.pkts_out = tim; 2689 log.u_bbr.bw_inuse = bbr->r_ctl.rc_lt_bw; 2690 if (bbr->rc_lt_use_bw == 0) 2691 log.u_bbr.epoch = bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_lt_epoch; 2692 else 2693 log.u_bbr.epoch = bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_lt_epoch_use; 2694 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2695 &bbr->rc_inp->inp_socket->so_rcv, 2696 &bbr->rc_inp->inp_socket->so_snd, 2697 BBR_LOG_BWSAMP, 0, 2698 0, &log, false, &bbr->rc_tv); 2699 } 2700 } 2701 2702 static inline void 2703 bbr_log_progress_event(struct tcp_bbr *bbr, struct tcpcb *tp, uint32_t tick, int event, int line) 2704 { 2705 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) { 2706 union tcp_log_stackspecific log; 2707 2708 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime); 2709 log.u_bbr.flex1 = line; 2710 log.u_bbr.flex2 = tick; 2711 log.u_bbr.flex3 = tp->t_maxunacktime; 2712 log.u_bbr.flex4 = tp->t_acktime; 2713 log.u_bbr.flex8 = event; 2714 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2715 &bbr->rc_inp->inp_socket->so_rcv, 2716 &bbr->rc_inp->inp_socket->so_snd, 2717 BBR_LOG_PROGRESS, 0, 2718 0, &log, false, &bbr->rc_tv); 2719 } 2720 } 2721 2722 static void 2723 bbr_type_log_hdwr_pacing(struct tcp_bbr *bbr, const struct ifnet *ifp, 2724 uint64_t rate, uint64_t hw_rate, int line, uint32_t cts, 2725 int error) 2726 { 2727 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2728 union tcp_log_stackspecific log; 2729 2730 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2731 log.u_bbr.flex1 = ((hw_rate >> 32) & 0x00000000ffffffff); 2732 log.u_bbr.flex2 = (hw_rate & 0x00000000ffffffff); 2733 log.u_bbr.flex3 = (((uint64_t)ifp >> 32) & 0x00000000ffffffff); 2734 log.u_bbr.flex4 = ((uint64_t)ifp & 0x00000000ffffffff); 2735 log.u_bbr.bw_inuse = rate; 2736 log.u_bbr.flex5 = line; 2737 log.u_bbr.flex6 = error; 2738 log.u_bbr.flex8 = bbr->skip_gain; 2739 log.u_bbr.flex8 <<= 1; 2740 log.u_bbr.flex8 |= bbr->gain_is_limited; 2741 log.u_bbr.flex8 <<= 1; 2742 log.u_bbr.flex8 |= bbr->bbr_hdrw_pacing; 2743 log.u_bbr.pkts_out = bbr->rc_tp->t_maxseg; 2744 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2745 &bbr->rc_inp->inp_socket->so_rcv, 2746 &bbr->rc_inp->inp_socket->so_snd, 2747 BBR_LOG_HDWR_PACE, 0, 2748 0, &log, false, &bbr->rc_tv); 2749 } 2750 } 2751 2752 static void 2753 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) 2754 { 2755 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2756 union tcp_log_stackspecific log; 2757 2758 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2759 log.u_bbr.flex1 = slot; 2760 log.u_bbr.flex2 = del_by; 2761 log.u_bbr.flex3 = prev_delay; 2762 log.u_bbr.flex4 = line; 2763 log.u_bbr.flex5 = bbr->r_ctl.rc_last_delay_val; 2764 log.u_bbr.flex6 = bbr->r_ctl.rc_hptsi_agg_delay; 2765 log.u_bbr.flex7 = (0x0000ffff & bbr->r_ctl.rc_hpts_flags); 2766 log.u_bbr.flex8 = bbr->rc_in_persist; 2767 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2768 &bbr->rc_inp->inp_socket->so_rcv, 2769 &bbr->rc_inp->inp_socket->so_snd, 2770 BBR_LOG_BBRSND, 0, 2771 len, &log, false, &bbr->rc_tv); 2772 } 2773 } 2774 2775 static void 2776 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) 2777 { 2778 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2779 union tcp_log_stackspecific log; 2780 2781 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2782 log.u_bbr.flex1 = bbr->r_ctl.rc_delivered; 2783 log.u_bbr.flex2 = 0; 2784 log.u_bbr.flex3 = bbr->r_ctl.rc_lowest_rtt; 2785 log.u_bbr.flex4 = end; 2786 log.u_bbr.flex5 = seq; 2787 log.u_bbr.flex6 = t; 2788 log.u_bbr.flex7 = match; 2789 log.u_bbr.flex8 = flags; 2790 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2791 &bbr->rc_inp->inp_socket->so_rcv, 2792 &bbr->rc_inp->inp_socket->so_snd, 2793 BBR_LOG_BBRRTT, 0, 2794 0, &log, false, &bbr->rc_tv); 2795 } 2796 } 2797 2798 static void 2799 bbr_log_exit_gain(struct tcp_bbr *bbr, uint32_t cts, int32_t entry_method) 2800 { 2801 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) { 2802 union tcp_log_stackspecific log; 2803 2804 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 2805 log.u_bbr.flex1 = bbr->r_ctl.rc_target_at_state; 2806 log.u_bbr.flex2 = (bbr->rc_tp->t_maxseg - bbr->rc_last_options); 2807 log.u_bbr.flex3 = bbr->r_ctl.gain_epoch; 2808 log.u_bbr.flex4 = bbr->r_ctl.rc_pace_max_segs; 2809 log.u_bbr.flex5 = bbr->r_ctl.rc_pace_min_segs; 2810 log.u_bbr.flex6 = bbr->r_ctl.rc_bbr_state_atflight; 2811 log.u_bbr.flex7 = 0; 2812 log.u_bbr.flex8 = entry_method; 2813 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2814 &bbr->rc_inp->inp_socket->so_rcv, 2815 &bbr->rc_inp->inp_socket->so_snd, 2816 BBR_LOG_EXIT_GAIN, 0, 2817 0, &log, false, &bbr->rc_tv); 2818 } 2819 } 2820 2821 static void 2822 bbr_log_settings_change(struct tcp_bbr *bbr, int settings_desired) 2823 { 2824 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) { 2825 union tcp_log_stackspecific log; 2826 2827 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime); 2828 /* R-HU */ 2829 log.u_bbr.flex1 = 0; 2830 log.u_bbr.flex2 = 0; 2831 log.u_bbr.flex3 = 0; 2832 log.u_bbr.flex4 = 0; 2833 log.u_bbr.flex7 = 0; 2834 log.u_bbr.flex8 = settings_desired; 2835 2836 TCP_LOG_EVENTP(bbr->rc_tp, NULL, 2837 &bbr->rc_inp->inp_socket->so_rcv, 2838 &bbr->rc_inp->inp_socket->so_snd, 2839 BBR_LOG_SETTINGS_CHG, 0, 2840 0, &log, false, &bbr->rc_tv); 2841 } 2842 } 2843 2844 /* 2845 * Returns the bw from the our filter. 2846 */ 2847 static inline uint64_t 2848 bbr_get_full_bw(struct tcp_bbr *bbr) 2849 { 2850 uint64_t bw; 2851 2852 bw = get_filter_value(&bbr->r_ctl.rc_delrate); 2853 2854 return (bw); 2855 } 2856 2857 static inline void 2858 bbr_set_pktepoch(struct tcp_bbr *bbr, uint32_t cts, int32_t line) 2859 { 2860 uint64_t calclr; 2861 uint32_t lost, del; 2862 2863 if (bbr->r_ctl.rc_lost > bbr->r_ctl.rc_lost_at_pktepoch) 2864 lost = bbr->r_ctl.rc_lost - bbr->r_ctl.rc_lost_at_pktepoch; 2865 else 2866 lost = 0; 2867 del = bbr->r_ctl.rc_delivered - bbr->r_ctl.rc_pkt_epoch_del; 2868 if (lost == 0) { 2869 calclr = 0; 2870 } else if (del) { 2871 calclr = lost; 2872 calclr *= (uint64_t)1000; 2873 calclr /= (uint64_t)del; 2874 } else { 2875 /* Nothing delivered? 100.0% loss */ 2876 calclr = 1000; 2877 } 2878 bbr->r_ctl.rc_pkt_epoch_loss_rate = (uint32_t)calclr; 2879 if (IN_RECOVERY(bbr->rc_tp->t_flags)) 2880 bbr->r_ctl.recovery_lr += (uint32_t)calclr; 2881 bbr->r_ctl.rc_pkt_epoch++; 2882 if (bbr->rc_no_pacing && 2883 (bbr->r_ctl.rc_pkt_epoch >= bbr->no_pacing_until)) { 2884 bbr->rc_no_pacing = 0; 2885 tcp_bbr_tso_size_check(bbr, cts); 2886 } 2887 bbr->r_ctl.rc_pkt_epoch_rtt = bbr_calc_time(cts, bbr->r_ctl.rc_pkt_epoch_time); 2888 bbr->r_ctl.rc_pkt_epoch_time = cts; 2889 /* What was our loss rate */ 2890 bbr_log_pkt_epoch(bbr, cts, line, lost, del); 2891 bbr->r_ctl.rc_pkt_epoch_del = bbr->r_ctl.rc_delivered; 2892 bbr->r_ctl.rc_lost_at_pktepoch = bbr->r_ctl.rc_lost; 2893 } 2894 2895 static inline void 2896 bbr_set_epoch(struct tcp_bbr *bbr, uint32_t cts, int32_t line) 2897 { 2898 uint32_t epoch_time; 2899 2900 /* Tick the RTT clock */ 2901 bbr->r_ctl.rc_rtt_epoch++; 2902 epoch_time = cts - bbr->r_ctl.rc_rcv_epoch_start; 2903 bbr_log_time_epoch(bbr, cts, line, epoch_time); 2904 bbr->r_ctl.rc_rcv_epoch_start = cts; 2905 } 2906 2907 static inline void 2908 bbr_isit_a_pkt_epoch(struct tcp_bbr *bbr, uint32_t cts, struct bbr_sendmap *rsm, int32_t line, int32_t cum_acked) 2909 { 2910 if (SEQ_GEQ(rsm->r_delivered, bbr->r_ctl.rc_pkt_epoch_del)) { 2911 bbr->rc_is_pkt_epoch_now = 1; 2912 } 2913 } 2914 2915 /* 2916 * Returns the bw from either the b/w filter 2917 * or from the lt_bw (if the connection is being 2918 * policed). 2919 */ 2920 static inline uint64_t 2921 __bbr_get_bw(struct tcp_bbr *bbr) 2922 { 2923 uint64_t bw, min_bw; 2924 uint64_t rtt; 2925 int gm_measure_cnt = 1; 2926 2927 /* 2928 * For startup we make, like google, a 2929 * minimum b/w. This is generated from the 2930 * IW and the rttProp. We do fall back to srtt 2931 * if for some reason (initial handshake) we don't 2932 * have a rttProp. We, in the worst case, fall back 2933 * to the configured min_bw (rc_initial_hptsi_bw). 2934 */ 2935 if (bbr->rc_bbr_state == BBR_STATE_STARTUP) { 2936 /* Attempt first to use rttProp */ 2937 rtt = (uint64_t)get_filter_value_small(&bbr->r_ctl.rc_rttprop); 2938 if (rtt && (rtt < 0xffffffff)) { 2939 measure: 2940 min_bw = (uint64_t)(bbr_initial_cwnd(bbr, bbr->rc_tp)) * 2941 ((uint64_t)1000000); 2942 min_bw /= rtt; 2943 if (min_bw < bbr->r_ctl.rc_initial_hptsi_bw) { 2944 min_bw = bbr->r_ctl.rc_initial_hptsi_bw; 2945 } 2946 2947 } else if (bbr->rc_tp->t_srtt != 0) { 2948 /* No rttProp, use srtt? */ 2949 rtt = bbr_get_rtt(bbr, BBR_SRTT); 2950 goto measure; 2951 } else { 2952 min_bw = bbr->r_ctl.rc_initial_hptsi_bw; 2953 } 2954 } else 2955 min_bw = 0; 2956 2957 if ((bbr->rc_past_init_win == 0) && 2958 (bbr->r_ctl.rc_delivered > bbr_initial_cwnd(bbr, bbr->rc_tp))) 2959 bbr->rc_past_init_win = 1; 2960 if ((bbr->rc_use_google) && (bbr->r_ctl.r_measurement_count >= 1)) 2961 gm_measure_cnt = 0; 2962 if (gm_measure_cnt && 2963 ((bbr->r_ctl.r_measurement_count < bbr_min_measurements_req) || 2964 (bbr->rc_past_init_win == 0))) { 2965 /* For google we use our guess rate until we get 1 measurement */ 2966 2967 use_initial_window: 2968 rtt = (uint64_t)get_filter_value_small(&bbr->r_ctl.rc_rttprop); 2969 if (rtt && (rtt < 0xffffffff)) { 2970 /* 2971 * We have an RTT measurment. Use that in 2972 * combination with our initial window to calculate 2973 * a b/w. 2974 */ 2975 bw = (uint64_t)(bbr_initial_cwnd(bbr, bbr->rc_tp)) * 2976 ((uint64_t)1000000); 2977 bw /= rtt; 2978 if (bw < bbr->r_ctl.rc_initial_hptsi_bw) { 2979 bw = bbr->r_ctl.rc_initial_hptsi_bw; 2980 } 2981 } else { 2982 /* Drop back to the 40 and punt to a default */ 2983 bw = bbr->r_ctl.rc_initial_hptsi_bw; 2984 } 2985 if (bw < 1) 2986 /* Probably should panic */ 2987 bw = 1; 2988 if (bw > min_bw) 2989 return (bw); 2990 else 2991 return (min_bw); 2992 } 2993 if (bbr->rc_lt_use_bw) 2994 bw = bbr->r_ctl.rc_lt_bw; 2995 else if (bbr->r_recovery_bw && (bbr->rc_use_google == 0)) 2996 bw = bbr->r_ctl.red_bw; 2997 else 2998 bw = get_filter_value(&bbr->r_ctl.rc_delrate); 2999 if (bbr->rc_tp->t_peakrate_thr && (bbr->rc_use_google == 0)) { 3000 /* 3001 * Enforce user set rate limit, keep in mind that 3002 * t_peakrate_thr is in B/s already 3003 */ 3004 bw = uqmin((uint64_t)bbr->rc_tp->t_peakrate_thr, bw); 3005 } 3006 if (bw == 0) { 3007 /* We should not be at 0, go to the initial window then */ 3008 goto use_initial_window; 3009 } 3010 if (bw < 1) 3011 /* Probably should panic */ 3012 bw = 1; 3013 if (bw < min_bw) 3014 bw = min_bw; 3015 return (bw); 3016 } 3017 3018 static inline uint64_t 3019 bbr_get_bw(struct tcp_bbr *bbr) 3020 { 3021 uint64_t bw; 3022 3023 bw = __bbr_get_bw(bbr); 3024 return (bw); 3025 } 3026 3027 static inline void 3028 bbr_reset_lt_bw_interval(struct tcp_bbr *bbr, uint32_t cts) 3029 { 3030 bbr->r_ctl.rc_lt_epoch = bbr->r_ctl.rc_pkt_epoch; 3031 bbr->r_ctl.rc_lt_time = bbr->r_ctl.rc_del_time; 3032 bbr->r_ctl.rc_lt_del = bbr->r_ctl.rc_delivered; 3033 bbr->r_ctl.rc_lt_lost = bbr->r_ctl.rc_lost; 3034 } 3035 3036 static inline void 3037 bbr_reset_lt_bw_sampling(struct tcp_bbr *bbr, uint32_t cts) 3038 { 3039 bbr->rc_lt_is_sampling = 0; 3040 bbr->rc_lt_use_bw = 0; 3041 bbr->r_ctl.rc_lt_bw = 0; 3042 bbr_reset_lt_bw_interval(bbr, cts); 3043 } 3044 3045 static inline void 3046 bbr_lt_bw_samp_done(struct tcp_bbr *bbr, uint64_t bw, uint32_t cts, uint32_t timin) 3047 { 3048 uint64_t diff; 3049 3050 /* Do we have a previous sample? */ 3051 if (bbr->r_ctl.rc_lt_bw) { 3052 /* Get the diff in bytes per second */ 3053 if (bbr->r_ctl.rc_lt_bw > bw) 3054 diff = bbr->r_ctl.rc_lt_bw - bw; 3055 else 3056 diff = bw - bbr->r_ctl.rc_lt_bw; 3057 if ((diff <= bbr_lt_bw_diff) || 3058 (diff <= (bbr->r_ctl.rc_lt_bw / bbr_lt_bw_ratio))) { 3059 /* Consider us policed */ 3060 uint32_t saved_bw; 3061 3062 saved_bw = (uint32_t)bbr->r_ctl.rc_lt_bw; 3063 bbr->r_ctl.rc_lt_bw = (bw + bbr->r_ctl.rc_lt_bw) / 2; /* average of two */ 3064 bbr->rc_lt_use_bw = 1; 3065 bbr->r_ctl.rc_bbr_hptsi_gain = BBR_UNIT; 3066 /* 3067 * Use pkt based epoch for measuring length of 3068 * policer up 3069 */ 3070 bbr->r_ctl.rc_lt_epoch_use = bbr->r_ctl.rc_pkt_epoch; 3071 /* 3072 * reason 4 is we need to start consider being 3073 * policed 3074 */ 3075 bbr_log_type_ltbw(bbr, cts, 4, (uint32_t)bw, saved_bw, (uint32_t)diff, timin); 3076 return; 3077 } 3078 } 3079 bbr->r_ctl.rc_lt_bw = bw; 3080 bbr_reset_lt_bw_interval(bbr, cts); 3081 bbr_log_type_ltbw(bbr, cts, 5, 0, (uint32_t)bw, 0, timin); 3082 } 3083 3084 static void 3085 bbr_randomize_extra_state_time(struct tcp_bbr *bbr) 3086 { 3087 uint32_t ran, deduct; 3088 3089 ran = arc4random_uniform(bbr_rand_ot); 3090 if (ran) { 3091 deduct = bbr->r_ctl.rc_level_state_extra / ran; 3092 bbr->r_ctl.rc_level_state_extra -= deduct; 3093 } 3094 } 3095 /* 3096 * Return randomly the starting state 3097 * to use in probebw. 3098 */ 3099 static uint8_t 3100 bbr_pick_probebw_substate(struct tcp_bbr *bbr, uint32_t cts) 3101 { 3102 uint32_t ran; 3103 uint8_t ret_val; 3104 3105 /* Initialize the offset to 0 */ 3106 bbr->r_ctl.rc_exta_time_gd = 0; 3107 bbr->rc_hit_state_1 = 0; 3108 bbr->r_ctl.rc_level_state_extra = 0; 3109 ran = arc4random_uniform((BBR_SUBSTATE_COUNT-1)); 3110 /* 3111 * The math works funny here :) the return value is used to set the 3112 * substate and then the state change is called which increments by 3113 * one. So if we return 1 (DRAIN) we will increment to 2 (LEVEL1) when 3114 * we fully enter the state. Note that the (8 - 1 - ran) assures that 3115 * we return 1 - 7, so we dont return 0 and end up starting in 3116 * state 1 (DRAIN). 3117 */ 3118 ret_val = BBR_SUBSTATE_COUNT - 1 - ran; 3119 /* Set an epoch */ 3120 if ((cts - bbr->r_ctl.rc_rcv_epoch_start) >= bbr_get_rtt(bbr, BBR_RTT_PROP)) 3121 bbr_set_epoch(bbr, cts, __LINE__); 3122 3123 bbr->r_ctl.bbr_lost_at_state = bbr->r_ctl.rc_lost; 3124 return (ret_val); 3125 } 3126 3127 static void 3128 bbr_lt_bw_sampling(struct tcp_bbr *bbr, uint32_t cts, int32_t loss_detected) 3129 { 3130 uint32_t diff, d_time; 3131 uint64_t del_time, bw, lost, delivered; 3132 3133 if (bbr->r_use_policer == 0) 3134 return; 3135 if (bbr->rc_lt_use_bw) { 3136 /* We are using lt bw do we stop yet? */ 3137 diff = bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_lt_epoch_use; 3138 if (diff > bbr_lt_bw_max_rtts) { 3139 /* Reset it all */ 3140 reset_all: 3141 bbr_reset_lt_bw_sampling(bbr, cts); 3142 if (bbr->rc_filled_pipe) { 3143 bbr_set_epoch(bbr, cts, __LINE__); 3144 bbr->rc_bbr_substate = bbr_pick_probebw_substate(bbr, cts); 3145 bbr_substate_change(bbr, cts, __LINE__, 0); 3146 bbr->rc_bbr_state = BBR_STATE_PROBE_BW; 3147 bbr_log_type_statechange(bbr, cts, __LINE__); 3148 } else { 3149 /* 3150 * This should not happen really 3151 * unless we remove the startup/drain 3152 * restrictions above. 3153 */ 3154 bbr->rc_bbr_state = BBR_STATE_STARTUP; 3155 bbr_set_epoch(bbr, cts, __LINE__); 3156 bbr->r_ctl.rc_bbr_state_time = cts; 3157 bbr->r_ctl.rc_lost_at_startup = bbr->r_ctl.rc_lost; 3158 bbr->r_ctl.rc_bbr_hptsi_gain = bbr->r_ctl.rc_startup_pg; 3159 bbr->r_ctl.rc_bbr_cwnd_gain = bbr->r_ctl.rc_startup_pg; 3160 bbr_set_state_target(bbr, __LINE__); 3161 bbr_log_type_statechange(bbr, cts, __LINE__); 3162 } 3163 /* reason 0 is to stop using lt-bw */ 3164 bbr_log_type_ltbw(bbr, cts, 0, 0, 0, 0, 0); 3165 return; 3166 } 3167 if (bbr_lt_intvl_fp == 0) { 3168 /* Not doing false-postive detection */ 3169 return; 3170 } 3171 /* False positive detection */ 3172 if (diff == bbr_lt_intvl_fp) { 3173 /* At bbr_lt_intvl_fp we record the lost */ 3174 bbr->r_ctl.rc_lt_del = bbr->r_ctl.rc_delivered; 3175 bbr->r_ctl.rc_lt_lost = bbr->r_ctl.rc_lost; 3176 } else if (diff > (bbr_lt_intvl_min_rtts + bbr_lt_intvl_fp)) { 3177 /* Now is our loss rate still high? */ 3178 lost = bbr->r_ctl.rc_lost - bbr->r_ctl.rc_lt_lost; 3179 delivered = bbr->r_ctl.rc_delivered - bbr->r_ctl.rc_lt_del; 3180 if ((delivered == 0) || 3181 (((lost * 1000)/delivered) < bbr_lt_fd_thresh)) { 3182 /* No still below our threshold */ 3183 bbr_log_type_ltbw(bbr, cts, 7, lost, delivered, 0, 0); 3184 } else { 3185 /* Yikes its still high, it must be a false positive */ 3186 bbr_log_type_ltbw(bbr, cts, 8, lost, delivered, 0, 0); 3187 goto reset_all; 3188 } 3189 } 3190 return; 3191 } 3192 /* 3193 * Wait for the first loss before sampling, to let the policer 3194 * exhaust its tokens and estimate the steady-state rate allowed by 3195 * the policer. Starting samples earlier includes bursts that 3196 * over-estimate the bw. 3197 */ 3198 if (bbr->rc_lt_is_sampling == 0) { 3199 /* reason 1 is to begin doing the sampling */ 3200 if (loss_detected == 0) 3201 return; 3202 bbr_reset_lt_bw_interval(bbr, cts); 3203 bbr->rc_lt_is_sampling = 1; 3204 bbr_log_type_ltbw(bbr, cts, 1, 0, 0, 0, 0); 3205 return; 3206 } 3207 /* Now how long were we delivering long term last> */ 3208 if (TSTMP_GEQ(bbr->r_ctl.rc_del_time, bbr->r_ctl.rc_lt_time)) 3209 d_time = bbr->r_ctl.rc_del_time - bbr->r_ctl.rc_lt_time; 3210 else 3211 d_time = 0; 3212 3213 /* To avoid underestimates, reset sampling if we run out of data. */ 3214 if (bbr->r_ctl.r_app_limited_until) { 3215 /* Can not measure in app-limited state */ 3216 bbr_reset_lt_bw_sampling(bbr, cts); 3217 /* reason 2 is to reset sampling due to app limits */ 3218 bbr_log_type_ltbw(bbr, cts, 2, 0, 0, 0, d_time); 3219 return; 3220 } 3221 diff = bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_lt_epoch; 3222 if (diff < bbr_lt_intvl_min_rtts) { 3223 /* 3224 * need more samples (we don't 3225 * start on a round like linux so 3226 * we need 1 more). 3227 */ 3228 /* 6 is not_enough time or no-loss */ 3229 bbr_log_type_ltbw(bbr, cts, 6, 0, 0, 0, d_time); 3230 return; 3231 } 3232 if (diff > (4 * bbr_lt_intvl_min_rtts)) { 3233 /* 3234 * For now if we wait too long, reset all sampling. We need 3235 * to do some research here, its possible that we should 3236 * base this on how much loss as occurred.. something like 3237 * if its under 10% (or some thresh) reset all otherwise 3238 * don't. Thats for phase II I guess. 3239 */ 3240 bbr_reset_lt_bw_sampling(bbr, cts); 3241 /* reason 3 is to reset sampling due too long of sampling */ 3242 bbr_log_type_ltbw(bbr, cts, 3, 0, 0, 0, d_time); 3243 return; 3244 } 3245 /* 3246 * End sampling interval when a packet is lost, so we estimate the 3247 * policer tokens were exhausted. Stopping the sampling before the 3248 * tokens are exhausted under-estimates the policed rate. 3249 */ 3250 if (loss_detected == 0) { 3251 /* 6 is not_enough time or no-loss */ 3252 bbr_log_type_ltbw(bbr, cts, 6, 0, 0, 0, d_time); 3253 return; 3254 } 3255 /* Calculate packets lost and delivered in sampling interval. */ 3256 lost = bbr->r_ctl.rc_lost - bbr->r_ctl.rc_lt_lost; 3257 delivered = bbr->r_ctl.rc_delivered - bbr->r_ctl.rc_lt_del; 3258 if ((delivered == 0) || 3259 (((lost * 1000)/delivered) < bbr_lt_loss_thresh)) { 3260 bbr_log_type_ltbw(bbr, cts, 6, lost, delivered, 0, d_time); 3261 return; 3262 } 3263 if (d_time < 1000) { 3264 /* Not enough time. wait */ 3265 /* 6 is not_enough time or no-loss */ 3266 bbr_log_type_ltbw(bbr, cts, 6, 0, 0, 0, d_time); 3267 return; 3268 } 3269 if (d_time >= (0xffffffff / USECS_IN_MSEC)) { 3270 /* Too long */ 3271 bbr_reset_lt_bw_sampling(bbr, cts); 3272 /* reason 3 is to reset sampling due too long of sampling */ 3273 bbr_log_type_ltbw(bbr, cts, 3, 0, 0, 0, d_time); 3274 return; 3275 } 3276 del_time = d_time; 3277 bw = delivered; 3278 bw *= (uint64_t)USECS_IN_SECOND; 3279 bw /= del_time; 3280 bbr_lt_bw_samp_done(bbr, bw, cts, d_time); 3281 } 3282 3283 /* 3284 * Allocate a sendmap from our zone. 3285 */ 3286 static struct bbr_sendmap * 3287 bbr_alloc(struct tcp_bbr *bbr) 3288 { 3289 struct bbr_sendmap *rsm; 3290 3291 BBR_STAT_INC(bbr_to_alloc); 3292 rsm = uma_zalloc(bbr_zone, (M_NOWAIT | M_ZERO)); 3293 if (rsm) { 3294 bbr->r_ctl.rc_num_maps_alloced++; 3295 return (rsm); 3296 } 3297 if (bbr->r_ctl.rc_free_cnt) { 3298 BBR_STAT_INC(bbr_to_alloc_emerg); 3299 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_free); 3300 TAILQ_REMOVE(&bbr->r_ctl.rc_free, rsm, r_next); 3301 bbr->r_ctl.rc_free_cnt--; 3302 return (rsm); 3303 } 3304 BBR_STAT_INC(bbr_to_alloc_failed); 3305 return (NULL); 3306 } 3307 3308 static struct bbr_sendmap * 3309 bbr_alloc_full_limit(struct tcp_bbr *bbr) 3310 { 3311 if ((V_tcp_map_entries_limit > 0) && 3312 (bbr->r_ctl.rc_num_maps_alloced >= V_tcp_map_entries_limit)) { 3313 BBR_STAT_INC(bbr_alloc_limited); 3314 if (!bbr->alloc_limit_reported) { 3315 bbr->alloc_limit_reported = 1; 3316 BBR_STAT_INC(bbr_alloc_limited_conns); 3317 } 3318 return (NULL); 3319 } 3320 return (bbr_alloc(bbr)); 3321 } 3322 3323 /* wrapper to allocate a sendmap entry, subject to a specific limit */ 3324 static struct bbr_sendmap * 3325 bbr_alloc_limit(struct tcp_bbr *bbr, uint8_t limit_type) 3326 { 3327 struct bbr_sendmap *rsm; 3328 3329 if (limit_type) { 3330 /* currently there is only one limit type */ 3331 if (V_tcp_map_split_limit > 0 && 3332 bbr->r_ctl.rc_num_split_allocs >= V_tcp_map_split_limit) { 3333 BBR_STAT_INC(bbr_split_limited); 3334 if (!bbr->alloc_limit_reported) { 3335 bbr->alloc_limit_reported = 1; 3336 BBR_STAT_INC(bbr_alloc_limited_conns); 3337 } 3338 return (NULL); 3339 } 3340 } 3341 3342 /* allocate and mark in the limit type, if set */ 3343 rsm = bbr_alloc(bbr); 3344 if (rsm != NULL && limit_type) { 3345 rsm->r_limit_type = limit_type; 3346 bbr->r_ctl.rc_num_split_allocs++; 3347 } 3348 return (rsm); 3349 } 3350 3351 static void 3352 bbr_free(struct tcp_bbr *bbr, struct bbr_sendmap *rsm) 3353 { 3354 if (rsm->r_limit_type) { 3355 /* currently there is only one limit type */ 3356 bbr->r_ctl.rc_num_split_allocs--; 3357 } 3358 if (rsm->r_is_smallmap) 3359 bbr->r_ctl.rc_num_small_maps_alloced--; 3360 if (bbr->r_ctl.rc_tlp_send == rsm) 3361 bbr->r_ctl.rc_tlp_send = NULL; 3362 if (bbr->r_ctl.rc_resend == rsm) { 3363 bbr->r_ctl.rc_resend = NULL; 3364 } 3365 if (bbr->r_ctl.rc_next == rsm) 3366 bbr->r_ctl.rc_next = NULL; 3367 if (bbr->r_ctl.rc_sacklast == rsm) 3368 bbr->r_ctl.rc_sacklast = NULL; 3369 if (bbr->r_ctl.rc_free_cnt < bbr_min_req_free) { 3370 memset(rsm, 0, sizeof(struct bbr_sendmap)); 3371 TAILQ_INSERT_TAIL(&bbr->r_ctl.rc_free, rsm, r_next); 3372 rsm->r_limit_type = 0; 3373 bbr->r_ctl.rc_free_cnt++; 3374 return; 3375 } 3376 bbr->r_ctl.rc_num_maps_alloced--; 3377 uma_zfree(bbr_zone, rsm); 3378 } 3379 3380 /* 3381 * Returns the BDP. 3382 */ 3383 static uint64_t 3384 bbr_get_bw_delay_prod(uint64_t rtt, uint64_t bw) { 3385 /* 3386 * Calculate the bytes in flight needed given the bw (in bytes per 3387 * second) and the specifyed rtt in useconds. We need to put out the 3388 * returned value per RTT to match that rate. Gain will normaly 3389 * raise it up from there. 3390 * 3391 * This should not overflow as long as the bandwidth is below 1 3392 * TByte per second (bw < 10**12 = 2**40) and the rtt is smaller 3393 * than 1000 seconds (rtt < 10**3 * 10**6 = 10**9 = 2**30). 3394 */ 3395 uint64_t usec_per_sec; 3396 3397 usec_per_sec = USECS_IN_SECOND; 3398 return ((rtt * bw) / usec_per_sec); 3399 } 3400 3401 /* 3402 * Return the initial cwnd. 3403 */ 3404 static uint32_t 3405 bbr_initial_cwnd(struct tcp_bbr *bbr, struct tcpcb *tp) 3406 { 3407 uint32_t i_cwnd; 3408 3409 if (bbr->rc_init_win) { 3410 i_cwnd = bbr->rc_init_win * tp->t_maxseg; 3411 } else if (V_tcp_initcwnd_segments) 3412 i_cwnd = min((V_tcp_initcwnd_segments * tp->t_maxseg), 3413 max(2 * tp->t_maxseg, 14600)); 3414 else if (V_tcp_do_rfc3390) 3415 i_cwnd = min(4 * tp->t_maxseg, 3416 max(2 * tp->t_maxseg, 4380)); 3417 else { 3418 /* Per RFC5681 Section 3.1 */ 3419 if (tp->t_maxseg > 2190) 3420 i_cwnd = 2 * tp->t_maxseg; 3421 else if (tp->t_maxseg > 1095) 3422 i_cwnd = 3 * tp->t_maxseg; 3423 else 3424 i_cwnd = 4 * tp->t_maxseg; 3425 } 3426 return (i_cwnd); 3427 } 3428 3429 /* 3430 * Given a specified gain, return the target 3431 * cwnd based on that gain. 3432 */ 3433 static uint32_t 3434 bbr_get_raw_target_cwnd(struct tcp_bbr *bbr, uint32_t gain, uint64_t bw) 3435 { 3436 uint64_t bdp, rtt; 3437 uint32_t cwnd; 3438 3439 if ((get_filter_value_small(&bbr->r_ctl.rc_rttprop) == 0xffffffff) || 3440 (bbr_get_full_bw(bbr) == 0)) { 3441 /* No measurements yet */ 3442 return (bbr_initial_cwnd(bbr, bbr->rc_tp)); 3443 } 3444 /* 3445 * Get bytes per RTT needed (rttProp is normally in 3446 * bbr_cwndtarget_rtt_touse) 3447 */ 3448 rtt = bbr_get_rtt(bbr, bbr_cwndtarget_rtt_touse); 3449 /* Get the bdp from the two values */ 3450 bdp = bbr_get_bw_delay_prod(rtt, bw); 3451 /* Now apply the gain */ 3452 cwnd = (uint32_t)(((bdp * ((uint64_t)gain)) + (uint64_t)(BBR_UNIT - 1)) / ((uint64_t)BBR_UNIT)); 3453 3454 return (cwnd); 3455 } 3456 3457 static uint32_t 3458 bbr_get_target_cwnd(struct tcp_bbr *bbr, uint64_t bw, uint32_t gain) 3459 { 3460 uint32_t cwnd, mss; 3461 3462 mss = min((bbr->rc_tp->t_maxseg - bbr->rc_last_options), bbr->r_ctl.rc_pace_max_segs); 3463 /* Get the base cwnd with gain rounded to a mss */ 3464 cwnd = roundup(bbr_get_raw_target_cwnd(bbr, bw, gain), mss); 3465 /* 3466 * Add in N (2 default since we do not have a 3467 * fq layer to trap packets in) quanta's per the I-D 3468 * section 4.2.3.2 quanta adjust. 3469 */ 3470 cwnd += (bbr_quanta * bbr->r_ctl.rc_pace_max_segs); 3471 if (bbr->rc_use_google) { 3472 if((bbr->rc_bbr_state == BBR_STATE_PROBE_BW) && 3473 (bbr_state_val(bbr) == BBR_SUB_GAIN)) { 3474 /* 3475 * The linux implementation adds 3476 * an extra 2 x mss in gain cycle which 3477 * is documented no-where except in the code. 3478 * so we add more for Neal undocumented feature 3479 */ 3480 cwnd += 2 * mss; 3481 } 3482 if ((cwnd / mss) & 0x1) { 3483 /* Round up for odd num mss */ 3484 cwnd += mss; 3485 } 3486 } 3487 /* Are we below the min cwnd? */ 3488 if (cwnd < get_min_cwnd(bbr)) 3489 return (get_min_cwnd(bbr)); 3490 return (cwnd); 3491 } 3492 3493 static uint16_t 3494 bbr_gain_adjust(struct tcp_bbr *bbr, uint16_t gain) 3495 { 3496 if (gain < 1) 3497 gain = 1; 3498 return (gain); 3499 } 3500 3501 static uint32_t 3502 bbr_get_header_oh(struct tcp_bbr *bbr) 3503 { 3504 int seg_oh; 3505 3506 seg_oh = 0; 3507 if (bbr->r_ctl.rc_inc_tcp_oh) { 3508 /* Do we include TCP overhead? */ 3509 seg_oh = (bbr->rc_last_options + sizeof(struct tcphdr)); 3510 } 3511 if (bbr->r_ctl.rc_inc_ip_oh) { 3512 /* Do we include IP overhead? */ 3513 #ifdef INET6 3514 if (bbr->r_is_v6) 3515 seg_oh += sizeof(struct ip6_hdr); 3516 else 3517 #endif 3518 #ifdef INET 3519 seg_oh += sizeof(struct ip); 3520 #endif 3521 } 3522 if (bbr->r_ctl.rc_inc_enet_oh) { 3523 /* Do we include the ethernet overhead? */ 3524 seg_oh += sizeof(struct ether_header); 3525 } 3526 return(seg_oh); 3527 } 3528 3529 static uint32_t 3530 bbr_get_pacing_length(struct tcp_bbr *bbr, uint16_t gain, uint32_t useconds_time, uint64_t bw) 3531 { 3532 uint64_t divor, res, tim; 3533 3534 if (useconds_time == 0) 3535 return (0); 3536 gain = bbr_gain_adjust(bbr, gain); 3537 divor = (uint64_t)USECS_IN_SECOND * (uint64_t)BBR_UNIT; 3538 tim = useconds_time; 3539 res = (tim * bw * gain) / divor; 3540 if (res == 0) 3541 res = 1; 3542 return ((uint32_t)res); 3543 } 3544 3545 /* 3546 * Given a gain and a length return the delay in useconds that 3547 * should be used to evenly space out packets 3548 * on the connection (based on the gain factor). 3549 */ 3550 static uint32_t 3551 bbr_get_pacing_delay(struct tcp_bbr *bbr, uint16_t gain, int32_t len, uint32_t cts, int nolog) 3552 { 3553 uint64_t bw, lentim, res; 3554 uint32_t usecs, srtt, over = 0; 3555 uint32_t seg_oh, num_segs, maxseg; 3556 3557 if (len == 0) 3558 return (0); 3559 3560 maxseg = bbr->rc_tp->t_maxseg - bbr->rc_last_options; 3561 num_segs = (len + maxseg - 1) / maxseg; 3562 if (bbr->rc_use_google == 0) { 3563 seg_oh = bbr_get_header_oh(bbr); 3564 len += (num_segs * seg_oh); 3565 } 3566 gain = bbr_gain_adjust(bbr, gain); 3567 bw = bbr_get_bw(bbr); 3568 if (bbr->rc_use_google) { 3569 uint64_t cbw; 3570 3571 /* 3572 * Reduce the b/w by the google discount 3573 * factor 10 = 1%. 3574 */ 3575 cbw = bw * (uint64_t)(1000 - bbr->r_ctl.bbr_google_discount); 3576 cbw /= (uint64_t)1000; 3577 /* We don't apply a discount if it results in 0 */ 3578 if (cbw > 0) 3579 bw = cbw; 3580 } 3581 lentim = ((uint64_t)len * 3582 (uint64_t)USECS_IN_SECOND * 3583 (uint64_t)BBR_UNIT); 3584 res = lentim / ((uint64_t)gain * bw); 3585 if (res == 0) 3586 res = 1; 3587 usecs = (uint32_t)res; 3588 srtt = bbr_get_rtt(bbr, BBR_SRTT); 3589 if (bbr_hptsi_max_mul && bbr_hptsi_max_div && 3590 (bbr->rc_use_google == 0) && 3591 (usecs > ((srtt * bbr_hptsi_max_mul) / bbr_hptsi_max_div))) { 3592 /* 3593 * We cannot let the delay be more than 1/2 the srtt time. 3594 * Otherwise we cannot pace out or send properly. 3595 */ 3596 over = usecs = (srtt * bbr_hptsi_max_mul) / bbr_hptsi_max_div; 3597 BBR_STAT_INC(bbr_hpts_min_time); 3598 } 3599 if (!nolog) 3600 bbr_log_pacing_delay_calc(bbr, gain, len, cts, usecs, bw, over, 1); 3601 return (usecs); 3602 } 3603 3604 static void 3605 bbr_ack_received(struct tcpcb *tp, struct tcp_bbr *bbr, struct tcphdr *th, uint32_t bytes_this_ack, 3606 uint32_t sack_changed, uint32_t prev_acked, int32_t line, uint32_t losses) 3607 { 3608 INP_WLOCK_ASSERT(tp->t_inpcb); 3609 uint64_t bw; 3610 uint32_t cwnd, target_cwnd, saved_bytes, maxseg; 3611 int32_t meth; 3612 3613 #ifdef STATS 3614 if ((tp->t_flags & TF_GPUTINPROG) && 3615 SEQ_GEQ(th->th_ack, tp->gput_ack)) { 3616 /* 3617 * Strech acks and compressed acks will cause this to 3618 * oscillate but we are doing it the same way as the main 3619 * stack so it will be compariable (though possibly not 3620 * ideal). 3621 */ 3622 int32_t cgput; 3623 int64_t gput, time_stamp; 3624 3625 gput = (int64_t) (th->th_ack - tp->gput_seq) * 8; 3626 time_stamp = max(1, ((bbr->r_ctl.rc_rcvtime - tp->gput_ts) / 1000)); 3627 cgput = gput / time_stamp; 3628 stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_GPUT, 3629 cgput); 3630 if (tp->t_stats_gput_prev > 0) 3631 stats_voi_update_abs_s32(tp->t_stats, 3632 VOI_TCP_GPUT_ND, 3633 ((gput - tp->t_stats_gput_prev) * 100) / 3634 tp->t_stats_gput_prev); 3635 tp->t_flags &= ~TF_GPUTINPROG; 3636 tp->t_stats_gput_prev = cgput; 3637 } 3638 #endif 3639 if ((bbr->rc_bbr_state == BBR_STATE_PROBE_RTT) && 3640 ((bbr->r_ctl.bbr_rttprobe_gain_val == 0) || bbr->rc_use_google)) { 3641 /* We don't change anything in probe-rtt */ 3642 return; 3643 } 3644 maxseg = tp->t_maxseg - bbr->rc_last_options; 3645 saved_bytes = bytes_this_ack; 3646 bytes_this_ack += sack_changed; 3647 if (bytes_this_ack > prev_acked) { 3648 bytes_this_ack -= prev_acked; 3649 /* 3650 * A byte ack'd gives us a full mss 3651 * to be like linux i.e. they count packets. 3652 */ 3653 if ((bytes_this_ack < maxseg) && bbr->rc_use_google) 3654 bytes_this_ack = maxseg; 3655 } else { 3656 /* Unlikely */ 3657 bytes_this_ack = 0; 3658 } 3659 cwnd = tp->snd_cwnd; 3660 bw = get_filter_value(&bbr->r_ctl.rc_delrate); 3661 if (bw) 3662 target_cwnd = bbr_get_target_cwnd(bbr, 3663 bw, 3664 (uint32_t)bbr->r_ctl.rc_bbr_cwnd_gain); 3665 else 3666 target_cwnd = bbr_initial_cwnd(bbr, bbr->rc_tp); 3667 if (IN_RECOVERY(tp->t_flags) && 3668 (bbr->bbr_prev_in_rec == 0)) { 3669 /* 3670 * We are entering recovery and 3671 * thus packet conservation. 3672 */ 3673 bbr->pkt_conservation = 1; 3674 bbr->r_ctl.rc_recovery_start = bbr->r_ctl.rc_rcvtime; 3675 cwnd = ctf_flight_size(tp, 3676 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)) + 3677 bytes_this_ack; 3678 } 3679 if (IN_RECOVERY(tp->t_flags)) { 3680 uint32_t flight; 3681 3682 bbr->bbr_prev_in_rec = 1; 3683 if (cwnd > losses) { 3684 cwnd -= losses; 3685 if (cwnd < maxseg) 3686 cwnd = maxseg; 3687 } else 3688 cwnd = maxseg; 3689 flight = ctf_flight_size(tp, 3690 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 3691 bbr_log_type_cwndupd(bbr, flight, 0, 3692 losses, 10, 0, 0, line); 3693 if (bbr->pkt_conservation) { 3694 uint32_t time_in; 3695 3696 if (TSTMP_GEQ(bbr->r_ctl.rc_rcvtime, bbr->r_ctl.rc_recovery_start)) 3697 time_in = bbr->r_ctl.rc_rcvtime - bbr->r_ctl.rc_recovery_start; 3698 else 3699 time_in = 0; 3700 3701 if (time_in >= bbr_get_rtt(bbr, BBR_RTT_PROP)) { 3702 /* Clear packet conservation after an rttProp */ 3703 bbr->pkt_conservation = 0; 3704 } else { 3705 if ((flight + bytes_this_ack) > cwnd) 3706 cwnd = flight + bytes_this_ack; 3707 if (cwnd < get_min_cwnd(bbr)) 3708 cwnd = get_min_cwnd(bbr); 3709 tp->snd_cwnd = cwnd; 3710 bbr_log_type_cwndupd(bbr, saved_bytes, sack_changed, 3711 prev_acked, 1, target_cwnd, th->th_ack, line); 3712 return; 3713 } 3714 } 3715 } else 3716 bbr->bbr_prev_in_rec = 0; 3717 if ((bbr->rc_use_google == 0) && bbr->r_ctl.restrict_growth) { 3718 bbr->r_ctl.restrict_growth--; 3719 if (bytes_this_ack > maxseg) 3720 bytes_this_ack = maxseg; 3721 } 3722 if (bbr->rc_filled_pipe) { 3723 /* 3724 * Here we have exited startup and filled the pipe. We will 3725 * thus allow the cwnd to shrink to the target. We hit here 3726 * mostly. 3727 */ 3728 uint32_t s_cwnd; 3729 3730 meth = 2; 3731 s_cwnd = min((cwnd + bytes_this_ack), target_cwnd); 3732 if (s_cwnd > cwnd) 3733 cwnd = s_cwnd; 3734 else if (bbr_cwnd_may_shrink || bbr->rc_use_google || bbr->rc_no_pacing) 3735 cwnd = s_cwnd; 3736 } else { 3737 /* 3738 * Here we are still in startup, we increase cwnd by what 3739 * has been acked. 3740 */ 3741 if ((cwnd < target_cwnd) || 3742 (bbr->rc_past_init_win == 0)) { 3743 meth = 3; 3744 cwnd += bytes_this_ack; 3745 } else { 3746 /* 3747 * Method 4 means we are at target so no gain in 3748 * startup and past the initial window. 3749 */ 3750 meth = 4; 3751 } 3752 } 3753 tp->snd_cwnd = max(cwnd, get_min_cwnd(bbr)); 3754 bbr_log_type_cwndupd(bbr, saved_bytes, sack_changed, prev_acked, meth, target_cwnd, th->th_ack, line); 3755 } 3756 3757 static void 3758 tcp_bbr_partialack(struct tcpcb *tp) 3759 { 3760 struct tcp_bbr *bbr; 3761 3762 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 3763 INP_WLOCK_ASSERT(tp->t_inpcb); 3764 if (ctf_flight_size(tp, 3765 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)) <= 3766 tp->snd_cwnd) { 3767 bbr->r_wanted_output = 1; 3768 } 3769 } 3770 3771 static void 3772 bbr_post_recovery(struct tcpcb *tp) 3773 { 3774 struct tcp_bbr *bbr; 3775 uint32_t flight; 3776 3777 INP_WLOCK_ASSERT(tp->t_inpcb); 3778 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 3779 /* 3780 * Here we just exit recovery. 3781 */ 3782 EXIT_RECOVERY(tp->t_flags); 3783 /* Lock in our b/w reduction for the specified number of pkt-epochs */ 3784 bbr->r_recovery_bw = 0; 3785 tp->snd_recover = tp->snd_una; 3786 tcp_bbr_tso_size_check(bbr, bbr->r_ctl.rc_rcvtime); 3787 bbr->pkt_conservation = 0; 3788 if (bbr->rc_use_google == 0) { 3789 /* 3790 * For non-google mode lets 3791 * go ahead and make sure we clear 3792 * the recovery state so if we 3793 * bounce back in to recovery we 3794 * will do PC. 3795 */ 3796 bbr->bbr_prev_in_rec = 0; 3797 } 3798 bbr_log_type_exit_rec(bbr); 3799 if (bbr->rc_bbr_state != BBR_STATE_PROBE_RTT) { 3800 tp->snd_cwnd = max(tp->snd_cwnd, bbr->r_ctl.rc_cwnd_on_ent); 3801 bbr_log_type_cwndupd(bbr, 0, 0, 0, 15, 0, 0, __LINE__); 3802 } else { 3803 /* For probe-rtt case lets fix up its saved_cwnd */ 3804 if (bbr->r_ctl.rc_saved_cwnd < bbr->r_ctl.rc_cwnd_on_ent) { 3805 bbr->r_ctl.rc_saved_cwnd = bbr->r_ctl.rc_cwnd_on_ent; 3806 bbr_log_type_cwndupd(bbr, 0, 0, 0, 16, 0, 0, __LINE__); 3807 } 3808 } 3809 flight = ctf_flight_size(tp, 3810 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 3811 if ((bbr->rc_use_google == 0) && 3812 bbr_do_red) { 3813 uint64_t val, lr2use; 3814 uint32_t maxseg, newcwnd, acks_inflight, ratio, cwnd; 3815 uint32_t *cwnd_p; 3816 3817 if (bbr_get_rtt(bbr, BBR_SRTT)) { 3818 val = ((uint64_t)bbr_get_rtt(bbr, BBR_RTT_PROP) * (uint64_t)1000); 3819 val /= bbr_get_rtt(bbr, BBR_SRTT); 3820 ratio = (uint32_t)val; 3821 } else 3822 ratio = 1000; 3823 3824 bbr_log_type_cwndupd(bbr, bbr_red_mul, bbr_red_div, 3825 bbr->r_ctl.recovery_lr, 21, 3826 ratio, 3827 bbr->r_ctl.rc_red_cwnd_pe, 3828 __LINE__); 3829 if ((ratio < bbr_do_red) || (bbr_do_red == 0)) 3830 goto done; 3831 if (((bbr->rc_bbr_state == BBR_STATE_PROBE_RTT) && 3832 bbr_prtt_slam_cwnd) || 3833 (bbr_sub_drain_slam_cwnd && 3834 (bbr->rc_bbr_state == BBR_STATE_PROBE_BW) && 3835 bbr->rc_hit_state_1 && 3836 (bbr_state_val(bbr) == BBR_SUB_DRAIN)) || 3837 ((bbr->rc_bbr_state == BBR_STATE_DRAIN) && 3838 bbr_slam_cwnd_in_main_drain)) { 3839 /* 3840 * Here we must poke at the saved cwnd 3841 * as well as the cwnd. 3842 */ 3843 cwnd = bbr->r_ctl.rc_saved_cwnd; 3844 cwnd_p = &bbr->r_ctl.rc_saved_cwnd; 3845 } else { 3846 cwnd = tp->snd_cwnd; 3847 cwnd_p = &tp->snd_cwnd; 3848 } 3849 maxseg = tp->t_maxseg - bbr->rc_last_options; 3850 /* Add the overall lr with the recovery lr */ 3851 if (bbr->r_ctl.rc_lost == 0) 3852 lr2use = 0; 3853 else if (bbr->r_ctl.rc_delivered == 0) 3854 lr2use = 1000; 3855 else { 3856 lr2use = bbr->r_ctl.rc_lost * 1000; 3857 lr2use /= bbr->r_ctl.rc_delivered; 3858 } 3859 lr2use += bbr->r_ctl.recovery_lr; 3860 acks_inflight = (flight / (maxseg * 2)); 3861 if (bbr_red_scale) { 3862 lr2use *= bbr_get_rtt(bbr, BBR_SRTT); 3863 lr2use /= bbr_red_scale; 3864 if ((bbr_red_growth_restrict) && 3865 ((bbr_get_rtt(bbr, BBR_SRTT)/bbr_red_scale) > 1)) 3866 bbr->r_ctl.restrict_growth += acks_inflight; 3867 } 3868 if (lr2use) { 3869 val = (uint64_t)cwnd * lr2use; 3870 val /= 1000; 3871 if (cwnd > val) 3872 newcwnd = roundup((cwnd - val), maxseg); 3873 else 3874 newcwnd = maxseg; 3875 } else { 3876 val = (uint64_t)cwnd * (uint64_t)bbr_red_mul; 3877 val /= (uint64_t)bbr_red_div; 3878 newcwnd = roundup((uint32_t)val, maxseg); 3879 } 3880 /* with standard delayed acks how many acks can I expect? */ 3881 if (bbr_drop_limit == 0) { 3882 /* 3883 * Anticpate how much we will 3884 * raise the cwnd based on the acks. 3885 */ 3886 if ((newcwnd + (acks_inflight * maxseg)) < get_min_cwnd(bbr)) { 3887 /* We do enforce the min (with the acks) */ 3888 newcwnd = (get_min_cwnd(bbr) - acks_inflight); 3889 } 3890 } else { 3891 /* 3892 * A strict drop limit of N is is inplace 3893 */ 3894 if (newcwnd < (bbr_drop_limit * maxseg)) { 3895 newcwnd = bbr_drop_limit * maxseg; 3896 } 3897 } 3898 /* For the next N acks do we restrict the growth */ 3899 *cwnd_p = newcwnd; 3900 if (tp->snd_cwnd > newcwnd) 3901 tp->snd_cwnd = newcwnd; 3902 bbr_log_type_cwndupd(bbr, bbr_red_mul, bbr_red_div, val, 22, 3903 (uint32_t)lr2use, 3904 bbr_get_rtt(bbr, BBR_SRTT), __LINE__); 3905 bbr->r_ctl.rc_red_cwnd_pe = bbr->r_ctl.rc_pkt_epoch; 3906 } 3907 done: 3908 bbr->r_ctl.recovery_lr = 0; 3909 if (flight <= tp->snd_cwnd) { 3910 bbr->r_wanted_output = 1; 3911 } 3912 tcp_bbr_tso_size_check(bbr, bbr->r_ctl.rc_rcvtime); 3913 } 3914 3915 static void 3916 bbr_setup_red_bw(struct tcp_bbr *bbr, uint32_t cts) 3917 { 3918 bbr->r_ctl.red_bw = get_filter_value(&bbr->r_ctl.rc_delrate); 3919 /* Limit the drop in b/w to 1/2 our current filter. */ 3920 if (bbr->r_ctl.red_bw > bbr->r_ctl.rc_bbr_cur_del_rate) 3921 bbr->r_ctl.red_bw = bbr->r_ctl.rc_bbr_cur_del_rate; 3922 if (bbr->r_ctl.red_bw < (get_filter_value(&bbr->r_ctl.rc_delrate) / 2)) 3923 bbr->r_ctl.red_bw = get_filter_value(&bbr->r_ctl.rc_delrate) / 2; 3924 tcp_bbr_tso_size_check(bbr, cts); 3925 } 3926 3927 static void 3928 bbr_cong_signal(struct tcpcb *tp, struct tcphdr *th, uint32_t type, struct bbr_sendmap *rsm) 3929 { 3930 struct tcp_bbr *bbr; 3931 3932 INP_WLOCK_ASSERT(tp->t_inpcb); 3933 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 3934 switch (type) { 3935 case CC_NDUPACK: 3936 if (!IN_RECOVERY(tp->t_flags)) { 3937 tp->snd_recover = tp->snd_max; 3938 /* Start a new epoch */ 3939 bbr_set_pktepoch(bbr, bbr->r_ctl.rc_rcvtime, __LINE__); 3940 if (bbr->rc_lt_is_sampling || bbr->rc_lt_use_bw) { 3941 /* 3942 * Move forward the lt epoch 3943 * so it won't count the truncated 3944 * epoch. 3945 */ 3946 bbr->r_ctl.rc_lt_epoch++; 3947 } 3948 if (bbr->rc_bbr_state == BBR_STATE_STARTUP) { 3949 /* 3950 * Just like the policer detection code 3951 * if we are in startup we must push 3952 * forward the last startup epoch 3953 * to hide the truncated PE. 3954 */ 3955 bbr->r_ctl.rc_bbr_last_startup_epoch++; 3956 } 3957 bbr->r_ctl.rc_cwnd_on_ent = tp->snd_cwnd; 3958 ENTER_RECOVERY(tp->t_flags); 3959 bbr->rc_tlp_rtx_out = 0; 3960 bbr->r_ctl.recovery_lr = bbr->r_ctl.rc_pkt_epoch_loss_rate; 3961 tcp_bbr_tso_size_check(bbr, bbr->r_ctl.rc_rcvtime); 3962 if (bbr->rc_inp->inp_in_hpts && 3963 ((bbr->r_ctl.rc_hpts_flags & PACE_TMR_RACK) == 0)) { 3964 /* 3965 * When we enter recovery, we need to restart 3966 * any timers. This may mean we gain an agg 3967 * early, which will be made up for at the last 3968 * rxt out. 3969 */ 3970 bbr->rc_timer_first = 1; 3971 bbr_timer_cancel(bbr, __LINE__, bbr->r_ctl.rc_rcvtime); 3972 } 3973 /* 3974 * Calculate a new cwnd based on to the current 3975 * delivery rate with no gain. We get the bdp 3976 * without gaining it up like we normally would and 3977 * we use the last cur_del_rate. 3978 */ 3979 if ((bbr->rc_use_google == 0) && 3980 (bbr->r_ctl.bbr_rttprobe_gain_val || 3981 (bbr->rc_bbr_state != BBR_STATE_PROBE_RTT))) { 3982 tp->snd_cwnd = ctf_flight_size(tp, 3983 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)) + 3984 (tp->t_maxseg - bbr->rc_last_options); 3985 if (tp->snd_cwnd < get_min_cwnd(bbr)) { 3986 /* We always gate to min cwnd */ 3987 tp->snd_cwnd = get_min_cwnd(bbr); 3988 } 3989 bbr_log_type_cwndupd(bbr, 0, 0, 0, 14, 0, 0, __LINE__); 3990 } 3991 bbr_log_type_enter_rec(bbr, rsm->r_start); 3992 } 3993 break; 3994 case CC_RTO_ERR: 3995 KMOD_TCPSTAT_INC(tcps_sndrexmitbad); 3996 /* RTO was unnecessary, so reset everything. */ 3997 bbr_reset_lt_bw_sampling(bbr, bbr->r_ctl.rc_rcvtime); 3998 if (bbr->rc_bbr_state != BBR_STATE_PROBE_RTT) { 3999 tp->snd_cwnd = tp->snd_cwnd_prev; 4000 tp->snd_ssthresh = tp->snd_ssthresh_prev; 4001 tp->snd_recover = tp->snd_recover_prev; 4002 tp->snd_cwnd = max(tp->snd_cwnd, bbr->r_ctl.rc_cwnd_on_ent); 4003 bbr_log_type_cwndupd(bbr, 0, 0, 0, 13, 0, 0, __LINE__); 4004 } 4005 tp->t_badrxtwin = 0; 4006 break; 4007 } 4008 } 4009 4010 /* 4011 * Indicate whether this ack should be delayed. We can delay the ack if 4012 * following conditions are met: 4013 * - There is no delayed ack timer in progress. 4014 * - Our last ack wasn't a 0-sized window. We never want to delay 4015 * the ack that opens up a 0-sized window. 4016 * - LRO wasn't used for this segment. We make sure by checking that the 4017 * segment size is not larger than the MSS. 4018 * - Delayed acks are enabled or this is a half-synchronized T/TCP 4019 * connection. 4020 * - The data being acked is less than a full segment (a stretch ack 4021 * of more than a segment we should ack. 4022 * - nsegs is 1 (if its more than that we received more than 1 ack). 4023 */ 4024 #define DELAY_ACK(tp, bbr, nsegs) \ 4025 (((tp->t_flags & TF_RXWIN0SENT) == 0) && \ 4026 ((tp->t_flags & TF_DELACK) == 0) && \ 4027 ((bbr->bbr_segs_rcvd + nsegs) < tp->t_delayed_ack) && \ 4028 (tp->t_delayed_ack || (tp->t_flags & TF_NEEDSYN))) 4029 4030 /* 4031 * Return the lowest RSM in the map of 4032 * packets still in flight that is not acked. 4033 * This should normally find on the first one 4034 * since we remove packets from the send 4035 * map after they are marked ACKED. 4036 */ 4037 static struct bbr_sendmap * 4038 bbr_find_lowest_rsm(struct tcp_bbr *bbr) 4039 { 4040 struct bbr_sendmap *rsm; 4041 4042 /* 4043 * Walk the time-order transmitted list looking for an rsm that is 4044 * not acked. This will be the one that was sent the longest time 4045 * ago that is still outstanding. 4046 */ 4047 TAILQ_FOREACH(rsm, &bbr->r_ctl.rc_tmap, r_tnext) { 4048 if (rsm->r_flags & BBR_ACKED) { 4049 continue; 4050 } 4051 goto finish; 4052 } 4053 finish: 4054 return (rsm); 4055 } 4056 4057 static struct bbr_sendmap * 4058 bbr_find_high_nonack(struct tcp_bbr *bbr, struct bbr_sendmap *rsm) 4059 { 4060 struct bbr_sendmap *prsm; 4061 4062 /* 4063 * Walk the sequence order list backward until we hit and arrive at 4064 * the highest seq not acked. In theory when this is called it 4065 * should be the last segment (which it was not). 4066 */ 4067 prsm = rsm; 4068 TAILQ_FOREACH_REVERSE_FROM(prsm, &bbr->r_ctl.rc_map, bbr_head, r_next) { 4069 if (prsm->r_flags & (BBR_ACKED | BBR_HAS_FIN)) { 4070 continue; 4071 } 4072 return (prsm); 4073 } 4074 return (NULL); 4075 } 4076 4077 /* 4078 * Returns to the caller the number of microseconds that 4079 * the packet can be outstanding before we think we 4080 * should have had an ack returned. 4081 */ 4082 static uint32_t 4083 bbr_calc_thresh_rack(struct tcp_bbr *bbr, uint32_t srtt, uint32_t cts, struct bbr_sendmap *rsm) 4084 { 4085 /* 4086 * lro is the flag we use to determine if we have seen reordering. 4087 * If it gets set we have seen reordering. The reorder logic either 4088 * works in one of two ways: 4089 * 4090 * If reorder-fade is configured, then we track the last time we saw 4091 * re-ordering occur. If we reach the point where enough time as 4092 * passed we no longer consider reordering has occuring. 4093 * 4094 * Or if reorder-face is 0, then once we see reordering we consider 4095 * the connection to alway be subject to reordering and just set lro 4096 * to 1. 4097 * 4098 * In the end if lro is non-zero we add the extra time for 4099 * reordering in. 4100 */ 4101 int32_t lro; 4102 uint32_t thresh, t_rxtcur; 4103 4104 if (srtt == 0) 4105 srtt = 1; 4106 if (bbr->r_ctl.rc_reorder_ts) { 4107 if (bbr->r_ctl.rc_reorder_fade) { 4108 if (SEQ_GEQ(cts, bbr->r_ctl.rc_reorder_ts)) { 4109 lro = cts - bbr->r_ctl.rc_reorder_ts; 4110 if (lro == 0) { 4111 /* 4112 * No time as passed since the last 4113 * reorder, mark it as reordering. 4114 */ 4115 lro = 1; 4116 } 4117 } else { 4118 /* Negative time? */ 4119 lro = 0; 4120 } 4121 if (lro > bbr->r_ctl.rc_reorder_fade) { 4122 /* Turn off reordering seen too */ 4123 bbr->r_ctl.rc_reorder_ts = 0; 4124 lro = 0; 4125 } 4126 } else { 4127 /* Reodering does not fade */ 4128 lro = 1; 4129 } 4130 } else { 4131 lro = 0; 4132 } 4133 thresh = srtt + bbr->r_ctl.rc_pkt_delay; 4134 if (lro) { 4135 /* It must be set, if not you get 1/4 rtt */ 4136 if (bbr->r_ctl.rc_reorder_shift) 4137 thresh += (srtt >> bbr->r_ctl.rc_reorder_shift); 4138 else 4139 thresh += (srtt >> 2); 4140 } else { 4141 thresh += 1000; 4142 } 4143 /* We don't let the rack timeout be above a RTO */ 4144 if ((bbr->rc_tp)->t_srtt == 0) 4145 t_rxtcur = BBR_INITIAL_RTO; 4146 else 4147 t_rxtcur = TICKS_2_USEC(bbr->rc_tp->t_rxtcur); 4148 if (thresh > t_rxtcur) { 4149 thresh = t_rxtcur; 4150 } 4151 /* And we don't want it above the RTO max either */ 4152 if (thresh > (((uint32_t)bbr->rc_max_rto_sec) * USECS_IN_SECOND)) { 4153 thresh = (((uint32_t)bbr->rc_max_rto_sec) * USECS_IN_SECOND); 4154 } 4155 bbr_log_thresh_choice(bbr, cts, thresh, lro, srtt, rsm, BBR_TO_FRM_RACK); 4156 return (thresh); 4157 } 4158 4159 /* 4160 * Return to the caller the amount of time in mico-seconds 4161 * that should be used for the TLP timer from the last 4162 * send time of this packet. 4163 */ 4164 static uint32_t 4165 bbr_calc_thresh_tlp(struct tcpcb *tp, struct tcp_bbr *bbr, 4166 struct bbr_sendmap *rsm, uint32_t srtt, 4167 uint32_t cts) 4168 { 4169 uint32_t thresh, len, maxseg, t_rxtcur; 4170 struct bbr_sendmap *prsm; 4171 4172 if (srtt == 0) 4173 srtt = 1; 4174 if (bbr->rc_tlp_threshold) 4175 thresh = srtt + (srtt / bbr->rc_tlp_threshold); 4176 else 4177 thresh = (srtt * 2); 4178 maxseg = tp->t_maxseg - bbr->rc_last_options; 4179 /* Get the previous sent packet, if any */ 4180 len = rsm->r_end - rsm->r_start; 4181 4182 /* 2.1 behavior */ 4183 prsm = TAILQ_PREV(rsm, bbr_head, r_tnext); 4184 if (prsm && (len <= maxseg)) { 4185 /* 4186 * Two packets outstanding, thresh should be (2*srtt) + 4187 * possible inter-packet delay (if any). 4188 */ 4189 uint32_t inter_gap = 0; 4190 int idx, nidx; 4191 4192 idx = rsm->r_rtr_cnt - 1; 4193 nidx = prsm->r_rtr_cnt - 1; 4194 if (TSTMP_GEQ(rsm->r_tim_lastsent[nidx], prsm->r_tim_lastsent[idx])) { 4195 /* Yes it was sent later (or at the same time) */ 4196 inter_gap = rsm->r_tim_lastsent[idx] - prsm->r_tim_lastsent[nidx]; 4197 } 4198 thresh += inter_gap; 4199 } else if (len <= maxseg) { 4200 /* 4201 * Possibly compensate for delayed-ack. 4202 */ 4203 uint32_t alt_thresh; 4204 4205 alt_thresh = srtt + (srtt / 2) + bbr_delayed_ack_time; 4206 if (alt_thresh > thresh) 4207 thresh = alt_thresh; 4208 } 4209 /* Not above the current RTO */ 4210 if (tp->t_srtt == 0) 4211 t_rxtcur = BBR_INITIAL_RTO; 4212 else 4213 t_rxtcur = TICKS_2_USEC(tp->t_rxtcur); 4214 4215 bbr_log_thresh_choice(bbr, cts, thresh, t_rxtcur, srtt, rsm, BBR_TO_FRM_TLP); 4216 /* Not above an RTO */ 4217 if (thresh > t_rxtcur) { 4218 thresh = t_rxtcur; 4219 } 4220 /* Not above a RTO max */ 4221 if (thresh > (((uint32_t)bbr->rc_max_rto_sec) * USECS_IN_SECOND)) { 4222 thresh = (((uint32_t)bbr->rc_max_rto_sec) * USECS_IN_SECOND); 4223 } 4224 /* And now apply the user TLP min */ 4225 if (thresh < bbr_tlp_min) { 4226 thresh = bbr_tlp_min; 4227 } 4228 return (thresh); 4229 } 4230 4231 /* 4232 * Return one of three RTTs to use (in microseconds). 4233 */ 4234 static __inline uint32_t 4235 bbr_get_rtt(struct tcp_bbr *bbr, int32_t rtt_type) 4236 { 4237 uint32_t f_rtt; 4238 uint32_t srtt; 4239 4240 f_rtt = get_filter_value_small(&bbr->r_ctl.rc_rttprop); 4241 if (get_filter_value_small(&bbr->r_ctl.rc_rttprop) == 0xffffffff) { 4242 /* We have no rtt at all */ 4243 if (bbr->rc_tp->t_srtt == 0) 4244 f_rtt = BBR_INITIAL_RTO; 4245 else 4246 f_rtt = (TICKS_2_USEC(bbr->rc_tp->t_srtt) >> TCP_RTT_SHIFT); 4247 /* 4248 * Since we don't know how good the rtt is apply a 4249 * delayed-ack min 4250 */ 4251 if (f_rtt < bbr_delayed_ack_time) { 4252 f_rtt = bbr_delayed_ack_time; 4253 } 4254 } 4255 /* Take the filter version or last measured pkt-rtt */ 4256 if (rtt_type == BBR_RTT_PROP) { 4257 srtt = f_rtt; 4258 } else if (rtt_type == BBR_RTT_PKTRTT) { 4259 if (bbr->r_ctl.rc_pkt_epoch_rtt) { 4260 srtt = bbr->r_ctl.rc_pkt_epoch_rtt; 4261 } else { 4262 /* No pkt rtt yet */ 4263 srtt = f_rtt; 4264 } 4265 } else if (rtt_type == BBR_RTT_RACK) { 4266 srtt = bbr->r_ctl.rc_last_rtt; 4267 /* We need to add in any internal delay for our timer */ 4268 if (bbr->rc_ack_was_delayed) 4269 srtt += bbr->r_ctl.rc_ack_hdwr_delay; 4270 } else if (rtt_type == BBR_SRTT) { 4271 srtt = (TICKS_2_USEC(bbr->rc_tp->t_srtt) >> TCP_RTT_SHIFT); 4272 } else { 4273 /* TSNH */ 4274 srtt = f_rtt; 4275 #ifdef BBR_INVARIANTS 4276 panic("Unknown rtt request type %d", rtt_type); 4277 #endif 4278 } 4279 return (srtt); 4280 } 4281 4282 static int 4283 bbr_is_lost(struct tcp_bbr *bbr, struct bbr_sendmap *rsm, uint32_t cts) 4284 { 4285 uint32_t thresh; 4286 4287 thresh = bbr_calc_thresh_rack(bbr, bbr_get_rtt(bbr, BBR_RTT_RACK), 4288 cts, rsm); 4289 if ((cts - rsm->r_tim_lastsent[(rsm->r_rtr_cnt - 1)]) >= thresh) { 4290 /* It is lost (past time) */ 4291 return (1); 4292 } 4293 return (0); 4294 } 4295 4296 /* 4297 * Return a sendmap if we need to retransmit something. 4298 */ 4299 static struct bbr_sendmap * 4300 bbr_check_recovery_mode(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts) 4301 { 4302 /* 4303 * Check to see that we don't need to fall into recovery. We will 4304 * need to do so if our oldest transmit is past the time we should 4305 * have had an ack. 4306 */ 4307 4308 struct bbr_sendmap *rsm; 4309 int32_t idx; 4310 4311 if (TAILQ_EMPTY(&bbr->r_ctl.rc_map)) { 4312 /* Nothing outstanding that we know of */ 4313 return (NULL); 4314 } 4315 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_tmap); 4316 if (rsm == NULL) { 4317 /* Nothing in the transmit map */ 4318 return (NULL); 4319 } 4320 if (tp->t_flags & TF_SENTFIN) { 4321 /* Fin restricted, don't find anything once a fin is sent */ 4322 return (NULL); 4323 } 4324 if (rsm->r_flags & BBR_ACKED) { 4325 /* 4326 * Ok the first one is acked (this really should not happen 4327 * since we remove the from the tmap once they are acked) 4328 */ 4329 rsm = bbr_find_lowest_rsm(bbr); 4330 if (rsm == NULL) 4331 return (NULL); 4332 } 4333 idx = rsm->r_rtr_cnt - 1; 4334 if (SEQ_LEQ(cts, rsm->r_tim_lastsent[idx])) { 4335 /* Send timestamp is the same or less? can't be ready */ 4336 return (NULL); 4337 } 4338 /* Get our RTT time */ 4339 if (bbr_is_lost(bbr, rsm, cts) && 4340 ((rsm->r_dupack >= DUP_ACK_THRESHOLD) || 4341 (rsm->r_flags & BBR_SACK_PASSED))) { 4342 if ((rsm->r_flags & BBR_MARKED_LOST) == 0) { 4343 rsm->r_flags |= BBR_MARKED_LOST; 4344 bbr->r_ctl.rc_lost += rsm->r_end - rsm->r_start; 4345 bbr->r_ctl.rc_lost_bytes += rsm->r_end - rsm->r_start; 4346 } 4347 bbr_cong_signal(tp, NULL, CC_NDUPACK, rsm); 4348 #ifdef BBR_INVARIANTS 4349 if ((rsm->r_end - rsm->r_start) == 0) 4350 panic("tp:%p bbr:%p rsm:%p length is 0?", tp, bbr, rsm); 4351 #endif 4352 return (rsm); 4353 } 4354 return (NULL); 4355 } 4356 4357 /* 4358 * RACK Timer, here we simply do logging and house keeping. 4359 * the normal bbr_output_wtime() function will call the 4360 * appropriate thing to check if we need to do a RACK retransmit. 4361 * We return 1, saying don't proceed with bbr_output_wtime only 4362 * when all timers have been stopped (destroyed PCB?). 4363 */ 4364 static int 4365 bbr_timeout_rack(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts) 4366 { 4367 /* 4368 * This timer simply provides an internal trigger to send out data. 4369 * The check_recovery_mode call will see if there are needed 4370 * retransmissions, if so we will enter fast-recovery. The output 4371 * call may or may not do the same thing depending on sysctl 4372 * settings. 4373 */ 4374 uint32_t lost; 4375 4376 if (bbr->rc_all_timers_stopped) { 4377 return (1); 4378 } 4379 if (TSTMP_LT(cts, bbr->r_ctl.rc_timer_exp)) { 4380 /* Its not time yet */ 4381 return (0); 4382 } 4383 BBR_STAT_INC(bbr_to_tot); 4384 lost = bbr->r_ctl.rc_lost; 4385 if (bbr->r_state && (bbr->r_state != tp->t_state)) 4386 bbr_set_state(tp, bbr, 0); 4387 bbr_log_to_event(bbr, cts, BBR_TO_FRM_RACK); 4388 if (bbr->r_ctl.rc_resend == NULL) { 4389 /* Lets do the check here */ 4390 bbr->r_ctl.rc_resend = bbr_check_recovery_mode(tp, bbr, cts); 4391 } 4392 if (bbr_policer_call_from_rack_to) 4393 bbr_lt_bw_sampling(bbr, cts, (bbr->r_ctl.rc_lost > lost)); 4394 bbr->r_ctl.rc_hpts_flags &= ~PACE_TMR_RACK; 4395 return (0); 4396 } 4397 4398 static __inline void 4399 bbr_clone_rsm(struct tcp_bbr *bbr, struct bbr_sendmap *nrsm, struct bbr_sendmap *rsm, uint32_t start) 4400 { 4401 int idx; 4402 4403 nrsm->r_start = start; 4404 nrsm->r_end = rsm->r_end; 4405 nrsm->r_rtr_cnt = rsm->r_rtr_cnt; 4406 nrsm->r_flags = rsm->r_flags; 4407 /* We don't transfer forward the SYN flag */ 4408 nrsm->r_flags &= ~BBR_HAS_SYN; 4409 /* We move forward the FIN flag, not that this should happen */ 4410 rsm->r_flags &= ~BBR_HAS_FIN; 4411 nrsm->r_dupack = rsm->r_dupack; 4412 nrsm->r_rtr_bytes = 0; 4413 nrsm->r_is_gain = rsm->r_is_gain; 4414 nrsm->r_is_drain = rsm->r_is_drain; 4415 nrsm->r_delivered = rsm->r_delivered; 4416 nrsm->r_ts_valid = rsm->r_ts_valid; 4417 nrsm->r_del_ack_ts = rsm->r_del_ack_ts; 4418 nrsm->r_del_time = rsm->r_del_time; 4419 nrsm->r_app_limited = rsm->r_app_limited; 4420 nrsm->r_first_sent_time = rsm->r_first_sent_time; 4421 nrsm->r_flight_at_send = rsm->r_flight_at_send; 4422 /* We split a piece the lower section looses any just_ret flag. */ 4423 nrsm->r_bbr_state = rsm->r_bbr_state; 4424 for (idx = 0; idx < nrsm->r_rtr_cnt; idx++) { 4425 nrsm->r_tim_lastsent[idx] = rsm->r_tim_lastsent[idx]; 4426 } 4427 rsm->r_end = nrsm->r_start; 4428 idx = min((bbr->rc_tp->t_maxseg - bbr->rc_last_options), bbr->r_ctl.rc_pace_max_segs); 4429 idx /= 8; 4430 /* Check if we got too small */ 4431 if ((rsm->r_is_smallmap == 0) && 4432 ((rsm->r_end - rsm->r_start) <= idx)) { 4433 bbr->r_ctl.rc_num_small_maps_alloced++; 4434 rsm->r_is_smallmap = 1; 4435 } 4436 /* Check the new one as well */ 4437 if ((nrsm->r_end - nrsm->r_start) <= idx) { 4438 bbr->r_ctl.rc_num_small_maps_alloced++; 4439 nrsm->r_is_smallmap = 1; 4440 } 4441 } 4442 4443 static int 4444 bbr_sack_mergable(struct bbr_sendmap *at, 4445 uint32_t start, uint32_t end) 4446 { 4447 /* 4448 * Given a sack block defined by 4449 * start and end, and a current postion 4450 * at. Return 1 if either side of at 4451 * would show that the block is mergable 4452 * to that side. A block to be mergable 4453 * must have overlap with the start/end 4454 * and be in the SACK'd state. 4455 */ 4456 struct bbr_sendmap *l_rsm; 4457 struct bbr_sendmap *r_rsm; 4458 4459 /* first get the either side blocks */ 4460 l_rsm = TAILQ_PREV(at, bbr_head, r_next); 4461 r_rsm = TAILQ_NEXT(at, r_next); 4462 if (l_rsm && (l_rsm->r_flags & BBR_ACKED)) { 4463 /* Potentially mergeable */ 4464 if ((l_rsm->r_end == start) || 4465 (SEQ_LT(start, l_rsm->r_end) && 4466 SEQ_GT(end, l_rsm->r_end))) { 4467 /* 4468 * map blk |------| 4469 * sack blk |------| 4470 * <or> 4471 * map blk |------| 4472 * sack blk |------| 4473 */ 4474 return (1); 4475 } 4476 } 4477 if (r_rsm && (r_rsm->r_flags & BBR_ACKED)) { 4478 /* Potentially mergeable */ 4479 if ((r_rsm->r_start == end) || 4480 (SEQ_LT(start, r_rsm->r_start) && 4481 SEQ_GT(end, r_rsm->r_start))) { 4482 /* 4483 * map blk |---------| 4484 * sack blk |----| 4485 * <or> 4486 * map blk |---------| 4487 * sack blk |-------| 4488 */ 4489 return (1); 4490 } 4491 } 4492 return (0); 4493 } 4494 4495 static struct bbr_sendmap * 4496 bbr_merge_rsm(struct tcp_bbr *bbr, 4497 struct bbr_sendmap *l_rsm, 4498 struct bbr_sendmap *r_rsm) 4499 { 4500 /* 4501 * We are merging two ack'd RSM's, 4502 * the l_rsm is on the left (lower seq 4503 * values) and the r_rsm is on the right 4504 * (higher seq value). The simplest way 4505 * to merge these is to move the right 4506 * one into the left. I don't think there 4507 * is any reason we need to try to find 4508 * the oldest (or last oldest retransmitted). 4509 */ 4510 l_rsm->r_end = r_rsm->r_end; 4511 if (l_rsm->r_dupack < r_rsm->r_dupack) 4512 l_rsm->r_dupack = r_rsm->r_dupack; 4513 if (r_rsm->r_rtr_bytes) 4514 l_rsm->r_rtr_bytes += r_rsm->r_rtr_bytes; 4515 if (r_rsm->r_in_tmap) { 4516 /* This really should not happen */ 4517 TAILQ_REMOVE(&bbr->r_ctl.rc_tmap, r_rsm, r_tnext); 4518 } 4519 if (r_rsm->r_app_limited) 4520 l_rsm->r_app_limited = r_rsm->r_app_limited; 4521 /* Now the flags */ 4522 if (r_rsm->r_flags & BBR_HAS_FIN) 4523 l_rsm->r_flags |= BBR_HAS_FIN; 4524 if (r_rsm->r_flags & BBR_TLP) 4525 l_rsm->r_flags |= BBR_TLP; 4526 if (r_rsm->r_flags & BBR_RWND_COLLAPSED) 4527 l_rsm->r_flags |= BBR_RWND_COLLAPSED; 4528 if (r_rsm->r_flags & BBR_MARKED_LOST) { 4529 /* This really should not happen */ 4530 bbr->r_ctl.rc_lost_bytes -= r_rsm->r_end - r_rsm->r_start; 4531 } 4532 TAILQ_REMOVE(&bbr->r_ctl.rc_map, r_rsm, r_next); 4533 if ((r_rsm->r_limit_type == 0) && (l_rsm->r_limit_type != 0)) { 4534 /* Transfer the split limit to the map we free */ 4535 r_rsm->r_limit_type = l_rsm->r_limit_type; 4536 l_rsm->r_limit_type = 0; 4537 } 4538 bbr_free(bbr, r_rsm); 4539 return(l_rsm); 4540 } 4541 4542 /* 4543 * TLP Timer, here we simply setup what segment we want to 4544 * have the TLP expire on, the normal bbr_output_wtime() will then 4545 * send it out. 4546 * 4547 * We return 1, saying don't proceed with bbr_output_wtime only 4548 * when all timers have been stopped (destroyed PCB?). 4549 */ 4550 static int 4551 bbr_timeout_tlp(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts) 4552 { 4553 /* 4554 * Tail Loss Probe. 4555 */ 4556 struct bbr_sendmap *rsm = NULL; 4557 struct socket *so; 4558 uint32_t amm; 4559 uint32_t out, avail; 4560 uint32_t maxseg; 4561 int collapsed_win = 0; 4562 4563 if (bbr->rc_all_timers_stopped) { 4564 return (1); 4565 } 4566 if (TSTMP_LT(cts, bbr->r_ctl.rc_timer_exp)) { 4567 /* Its not time yet */ 4568 return (0); 4569 } 4570 if (ctf_progress_timeout_check(tp, true)) { 4571 bbr_log_progress_event(bbr, tp, tick, PROGRESS_DROP, __LINE__); 4572 tcp_set_inp_to_drop(bbr->rc_inp, ETIMEDOUT); 4573 return (1); 4574 } 4575 /* Did we somehow get into persists? */ 4576 if (bbr->rc_in_persist) { 4577 return (0); 4578 } 4579 if (bbr->r_state && (bbr->r_state != tp->t_state)) 4580 bbr_set_state(tp, bbr, 0); 4581 BBR_STAT_INC(bbr_tlp_tot); 4582 maxseg = tp->t_maxseg - bbr->rc_last_options; 4583 /* 4584 * A TLP timer has expired. We have been idle for 2 rtts. So we now 4585 * need to figure out how to force a full MSS segment out. 4586 */ 4587 so = tp->t_inpcb->inp_socket; 4588 avail = sbavail(&so->so_snd); 4589 out = ctf_outstanding(tp); 4590 if (out > tp->snd_wnd) { 4591 /* special case, we need a retransmission */ 4592 collapsed_win = 1; 4593 goto need_retran; 4594 } 4595 if (avail > out) { 4596 /* New data is available */ 4597 amm = avail - out; 4598 if (amm > maxseg) { 4599 amm = maxseg; 4600 } else if ((amm < maxseg) && ((tp->t_flags & TF_NODELAY) == 0)) { 4601 /* not enough to fill a MTU and no-delay is off */ 4602 goto need_retran; 4603 } 4604 /* Set the send-new override */ 4605 if ((out + amm) <= tp->snd_wnd) { 4606 bbr->rc_tlp_new_data = 1; 4607 } else { 4608 goto need_retran; 4609 } 4610 bbr->r_ctl.rc_tlp_seg_send_cnt = 0; 4611 bbr->r_ctl.rc_last_tlp_seq = tp->snd_max; 4612 bbr->r_ctl.rc_tlp_send = NULL; 4613 /* cap any slots */ 4614 BBR_STAT_INC(bbr_tlp_newdata); 4615 goto send; 4616 } 4617 need_retran: 4618 /* 4619 * Ok we need to arrange the last un-acked segment to be re-sent, or 4620 * optionally the first un-acked segment. 4621 */ 4622 if (collapsed_win == 0) { 4623 rsm = TAILQ_LAST_FAST(&bbr->r_ctl.rc_map, bbr_sendmap, r_next); 4624 if (rsm && (BBR_ACKED | BBR_HAS_FIN)) { 4625 rsm = bbr_find_high_nonack(bbr, rsm); 4626 } 4627 if (rsm == NULL) { 4628 goto restore; 4629 } 4630 } else { 4631 /* 4632 * We must find the last segment 4633 * that was acceptable by the client. 4634 */ 4635 TAILQ_FOREACH_REVERSE(rsm, &bbr->r_ctl.rc_map, bbr_head, r_next) { 4636 if ((rsm->r_flags & BBR_RWND_COLLAPSED) == 0) { 4637 /* Found one */ 4638 break; 4639 } 4640 } 4641 if (rsm == NULL) { 4642 /* None? if so send the first */ 4643 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map); 4644 if (rsm == NULL) 4645 goto restore; 4646 } 4647 } 4648 if ((rsm->r_end - rsm->r_start) > maxseg) { 4649 /* 4650 * We need to split this the last segment in two. 4651 */ 4652 struct bbr_sendmap *nrsm; 4653 4654 nrsm = bbr_alloc_full_limit(bbr); 4655 if (nrsm == NULL) { 4656 /* 4657 * We can't get memory to split, we can either just 4658 * not split it. Or retransmit the whole piece, lets 4659 * do the large send (BTLP :-) ). 4660 */ 4661 goto go_for_it; 4662 } 4663 bbr_clone_rsm(bbr, nrsm, rsm, (rsm->r_end - maxseg)); 4664 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_map, rsm, nrsm, r_next); 4665 if (rsm->r_in_tmap) { 4666 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, rsm, nrsm, r_tnext); 4667 nrsm->r_in_tmap = 1; 4668 } 4669 rsm->r_flags &= (~BBR_HAS_FIN); 4670 rsm = nrsm; 4671 } 4672 go_for_it: 4673 bbr->r_ctl.rc_tlp_send = rsm; 4674 bbr->rc_tlp_rtx_out = 1; 4675 if (rsm->r_start == bbr->r_ctl.rc_last_tlp_seq) { 4676 bbr->r_ctl.rc_tlp_seg_send_cnt++; 4677 tp->t_rxtshift++; 4678 } else { 4679 bbr->r_ctl.rc_last_tlp_seq = rsm->r_start; 4680 bbr->r_ctl.rc_tlp_seg_send_cnt = 1; 4681 } 4682 send: 4683 if (bbr->r_ctl.rc_tlp_seg_send_cnt > bbr_tlp_max_resend) { 4684 /* 4685 * Can't [re]/transmit a segment we have retranmitted the 4686 * max times. We need the retransmit timer to take over. 4687 */ 4688 restore: 4689 bbr->rc_tlp_new_data = 0; 4690 bbr->r_ctl.rc_tlp_send = NULL; 4691 if (rsm) 4692 rsm->r_flags &= ~BBR_TLP; 4693 BBR_STAT_INC(bbr_tlp_retran_fail); 4694 return (0); 4695 } else if (rsm) { 4696 rsm->r_flags |= BBR_TLP; 4697 } 4698 if (rsm && (rsm->r_start == bbr->r_ctl.rc_last_tlp_seq) && 4699 (bbr->r_ctl.rc_tlp_seg_send_cnt > bbr_tlp_max_resend)) { 4700 /* 4701 * We have retransmitted to many times for TLP. Switch to 4702 * the regular RTO timer 4703 */ 4704 goto restore; 4705 } 4706 bbr_log_to_event(bbr, cts, BBR_TO_FRM_TLP); 4707 bbr->r_ctl.rc_hpts_flags &= ~PACE_TMR_TLP; 4708 return (0); 4709 } 4710 4711 /* 4712 * Delayed ack Timer, here we simply need to setup the 4713 * ACK_NOW flag and remove the DELACK flag. From there 4714 * the output routine will send the ack out. 4715 * 4716 * We only return 1, saying don't proceed, if all timers 4717 * are stopped (destroyed PCB?). 4718 */ 4719 static int 4720 bbr_timeout_delack(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts) 4721 { 4722 if (bbr->rc_all_timers_stopped) { 4723 return (1); 4724 } 4725 bbr_log_to_event(bbr, cts, BBR_TO_FRM_DELACK); 4726 tp->t_flags &= ~TF_DELACK; 4727 tp->t_flags |= TF_ACKNOW; 4728 KMOD_TCPSTAT_INC(tcps_delack); 4729 bbr->r_ctl.rc_hpts_flags &= ~PACE_TMR_DELACK; 4730 return (0); 4731 } 4732 4733 /* 4734 * Here we send a KEEP-ALIVE like probe to the 4735 * peer, we do not send data. 4736 * 4737 * We only return 1, saying don't proceed, if all timers 4738 * are stopped (destroyed PCB?). 4739 */ 4740 static int 4741 bbr_timeout_persist(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts) 4742 { 4743 struct tcptemp *t_template; 4744 int32_t retval = 1; 4745 4746 if (bbr->rc_all_timers_stopped) { 4747 return (1); 4748 } 4749 if (bbr->rc_in_persist == 0) 4750 return (0); 4751 KASSERT(tp->t_inpcb != NULL, 4752 ("%s: tp %p tp->t_inpcb == NULL", __func__, tp)); 4753 /* 4754 * Persistence timer into zero window. Force a byte to be output, if 4755 * possible. 4756 */ 4757 bbr_log_to_event(bbr, cts, BBR_TO_FRM_PERSIST); 4758 bbr->r_ctl.rc_hpts_flags &= ~PACE_TMR_PERSIT; 4759 KMOD_TCPSTAT_INC(tcps_persisttimeo); 4760 /* 4761 * Have we exceeded the user specified progress time? 4762 */ 4763 if (ctf_progress_timeout_check(tp, true)) { 4764 bbr_log_progress_event(bbr, tp, tick, PROGRESS_DROP, __LINE__); 4765 tcp_set_inp_to_drop(bbr->rc_inp, ETIMEDOUT); 4766 goto out; 4767 } 4768 /* 4769 * Hack: if the peer is dead/unreachable, we do not time out if the 4770 * window is closed. After a full backoff, drop the connection if 4771 * the idle time (no responses to probes) reaches the maximum 4772 * backoff that we would use if retransmitting. 4773 */ 4774 if (tp->t_rxtshift == TCP_MAXRXTSHIFT && 4775 (ticks - tp->t_rcvtime >= tcp_maxpersistidle || 4776 ticks - tp->t_rcvtime >= TCP_REXMTVAL(tp) * tcp_totbackoff)) { 4777 KMOD_TCPSTAT_INC(tcps_persistdrop); 4778 tcp_log_end_status(tp, TCP_EI_STATUS_PERSIST_MAX); 4779 tcp_set_inp_to_drop(bbr->rc_inp, ETIMEDOUT); 4780 goto out; 4781 } 4782 if ((sbavail(&bbr->rc_inp->inp_socket->so_snd) == 0) && 4783 tp->snd_una == tp->snd_max) { 4784 bbr_exit_persist(tp, bbr, cts, __LINE__); 4785 retval = 0; 4786 goto out; 4787 } 4788 /* 4789 * If the user has closed the socket then drop a persisting 4790 * connection after a much reduced timeout. 4791 */ 4792 if (tp->t_state > TCPS_CLOSE_WAIT && 4793 (ticks - tp->t_rcvtime) >= TCPTV_PERSMAX) { 4794 KMOD_TCPSTAT_INC(tcps_persistdrop); 4795 tcp_log_end_status(tp, TCP_EI_STATUS_PERSIST_MAX); 4796 tcp_set_inp_to_drop(bbr->rc_inp, ETIMEDOUT); 4797 goto out; 4798 } 4799 t_template = tcpip_maketemplate(bbr->rc_inp); 4800 if (t_template) { 4801 tcp_respond(tp, t_template->tt_ipgen, 4802 &t_template->tt_t, (struct mbuf *)NULL, 4803 tp->rcv_nxt, tp->snd_una - 1, 0); 4804 /* This sends an ack */ 4805 if (tp->t_flags & TF_DELACK) 4806 tp->t_flags &= ~TF_DELACK; 4807 free(t_template, M_TEMP); 4808 } 4809 if (tp->t_rxtshift < TCP_MAXRXTSHIFT) 4810 tp->t_rxtshift++; 4811 bbr_start_hpts_timer(bbr, tp, cts, 3, 0, 0); 4812 out: 4813 return (retval); 4814 } 4815 4816 /* 4817 * If a keepalive goes off, we had no other timers 4818 * happening. We always return 1 here since this 4819 * routine either drops the connection or sends 4820 * out a segment with respond. 4821 */ 4822 static int 4823 bbr_timeout_keepalive(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts) 4824 { 4825 struct tcptemp *t_template; 4826 struct inpcb *inp; 4827 4828 if (bbr->rc_all_timers_stopped) { 4829 return (1); 4830 } 4831 bbr->r_ctl.rc_hpts_flags &= ~PACE_TMR_KEEP; 4832 inp = tp->t_inpcb; 4833 bbr_log_to_event(bbr, cts, BBR_TO_FRM_KEEP); 4834 /* 4835 * Keep-alive timer went off; send something or drop connection if 4836 * idle for too long. 4837 */ 4838 KMOD_TCPSTAT_INC(tcps_keeptimeo); 4839 if (tp->t_state < TCPS_ESTABLISHED) 4840 goto dropit; 4841 if ((V_tcp_always_keepalive || inp->inp_socket->so_options & SO_KEEPALIVE) && 4842 tp->t_state <= TCPS_CLOSING) { 4843 if (ticks - tp->t_rcvtime >= TP_KEEPIDLE(tp) + TP_MAXIDLE(tp)) 4844 goto dropit; 4845 /* 4846 * Send a packet designed to force a response if the peer is 4847 * up and reachable: either an ACK if the connection is 4848 * still alive, or an RST if the peer has closed the 4849 * connection due to timeout or reboot. Using sequence 4850 * number tp->snd_una-1 causes the transmitted zero-length 4851 * segment to lie outside the receive window; by the 4852 * protocol spec, this requires the correspondent TCP to 4853 * respond. 4854 */ 4855 KMOD_TCPSTAT_INC(tcps_keepprobe); 4856 t_template = tcpip_maketemplate(inp); 4857 if (t_template) { 4858 tcp_respond(tp, t_template->tt_ipgen, 4859 &t_template->tt_t, (struct mbuf *)NULL, 4860 tp->rcv_nxt, tp->snd_una - 1, 0); 4861 free(t_template, M_TEMP); 4862 } 4863 } 4864 bbr_start_hpts_timer(bbr, tp, cts, 4, 0, 0); 4865 return (1); 4866 dropit: 4867 KMOD_TCPSTAT_INC(tcps_keepdrops); 4868 tcp_log_end_status(tp, TCP_EI_STATUS_KEEP_MAX); 4869 tcp_set_inp_to_drop(bbr->rc_inp, ETIMEDOUT); 4870 return (1); 4871 } 4872 4873 /* 4874 * Retransmit helper function, clear up all the ack 4875 * flags and take care of important book keeping. 4876 */ 4877 static void 4878 bbr_remxt_tmr(struct tcpcb *tp) 4879 { 4880 /* 4881 * The retransmit timer went off, all sack'd blocks must be 4882 * un-acked. 4883 */ 4884 struct bbr_sendmap *rsm, *trsm = NULL; 4885 struct tcp_bbr *bbr; 4886 uint32_t cts, lost; 4887 4888 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 4889 cts = tcp_get_usecs(&bbr->rc_tv); 4890 lost = bbr->r_ctl.rc_lost; 4891 if (bbr->r_state && (bbr->r_state != tp->t_state)) 4892 bbr_set_state(tp, bbr, 0); 4893 4894 TAILQ_FOREACH(rsm, &bbr->r_ctl.rc_map, r_next) { 4895 if (rsm->r_flags & BBR_ACKED) { 4896 uint32_t old_flags; 4897 4898 rsm->r_dupack = 0; 4899 if (rsm->r_in_tmap == 0) { 4900 /* We must re-add it back to the tlist */ 4901 if (trsm == NULL) { 4902 TAILQ_INSERT_HEAD(&bbr->r_ctl.rc_tmap, rsm, r_tnext); 4903 } else { 4904 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, trsm, rsm, r_tnext); 4905 } 4906 rsm->r_in_tmap = 1; 4907 } 4908 old_flags = rsm->r_flags; 4909 rsm->r_flags |= BBR_RXT_CLEARED; 4910 rsm->r_flags &= ~(BBR_ACKED | BBR_SACK_PASSED | BBR_WAS_SACKPASS); 4911 bbr_log_type_rsmclear(bbr, cts, rsm, old_flags, __LINE__); 4912 } else { 4913 if ((tp->t_state < TCPS_ESTABLISHED) && 4914 (rsm->r_start == tp->snd_una)) { 4915 /* 4916 * Special case for TCP FO. Where 4917 * we sent more data beyond the snd_max. 4918 * We don't mark that as lost and stop here. 4919 */ 4920 break; 4921 } 4922 if ((rsm->r_flags & BBR_MARKED_LOST) == 0) { 4923 bbr->r_ctl.rc_lost += rsm->r_end - rsm->r_start; 4924 bbr->r_ctl.rc_lost_bytes += rsm->r_end - rsm->r_start; 4925 } 4926 if (bbr_marks_rxt_sack_passed) { 4927 /* 4928 * With this option, we will rack out 4929 * in 1ms increments the rest of the packets. 4930 */ 4931 rsm->r_flags |= BBR_SACK_PASSED | BBR_MARKED_LOST; 4932 rsm->r_flags &= ~BBR_WAS_SACKPASS; 4933 } else { 4934 /* 4935 * With this option we only mark them lost 4936 * and remove all sack'd markings. We will run 4937 * another RXT or a TLP. This will cause 4938 * us to eventually send more based on what 4939 * ack's come in. 4940 */ 4941 rsm->r_flags |= BBR_MARKED_LOST; 4942 rsm->r_flags &= ~BBR_WAS_SACKPASS; 4943 rsm->r_flags &= ~BBR_SACK_PASSED; 4944 } 4945 } 4946 trsm = rsm; 4947 } 4948 bbr->r_ctl.rc_resend = TAILQ_FIRST(&bbr->r_ctl.rc_map); 4949 /* Clear the count (we just un-acked them) */ 4950 bbr_log_to_event(bbr, cts, BBR_TO_FRM_TMR); 4951 bbr->rc_tlp_new_data = 0; 4952 bbr->r_ctl.rc_tlp_seg_send_cnt = 0; 4953 /* zap the behindness on a rxt */ 4954 bbr->r_ctl.rc_hptsi_agg_delay = 0; 4955 bbr->r_agg_early_set = 0; 4956 bbr->r_ctl.rc_agg_early = 0; 4957 bbr->rc_tlp_rtx_out = 0; 4958 bbr->r_ctl.rc_sacked = 0; 4959 bbr->r_ctl.rc_sacklast = NULL; 4960 bbr->r_timer_override = 1; 4961 bbr_lt_bw_sampling(bbr, cts, (bbr->r_ctl.rc_lost > lost)); 4962 } 4963 4964 /* 4965 * Re-transmit timeout! If we drop the PCB we will return 1, otherwise 4966 * we will setup to retransmit the lowest seq number outstanding. 4967 */ 4968 static int 4969 bbr_timeout_rxt(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts) 4970 { 4971 int32_t rexmt; 4972 int32_t retval = 0; 4973 bool isipv6; 4974 4975 bbr->r_ctl.rc_hpts_flags &= ~PACE_TMR_RXT; 4976 if (bbr->rc_all_timers_stopped) { 4977 return (1); 4978 } 4979 if (TCPS_HAVEESTABLISHED(tp->t_state) && 4980 (tp->snd_una == tp->snd_max)) { 4981 /* Nothing outstanding .. nothing to do */ 4982 return (0); 4983 } 4984 /* 4985 * Retransmission timer went off. Message has not been acked within 4986 * retransmit interval. Back off to a longer retransmit interval 4987 * and retransmit one segment. 4988 */ 4989 if (ctf_progress_timeout_check(tp, true)) { 4990 retval = 1; 4991 bbr_log_progress_event(bbr, tp, tick, PROGRESS_DROP, __LINE__); 4992 tcp_set_inp_to_drop(bbr->rc_inp, ETIMEDOUT); 4993 goto out; 4994 } 4995 bbr_remxt_tmr(tp); 4996 if ((bbr->r_ctl.rc_resend == NULL) || 4997 ((bbr->r_ctl.rc_resend->r_flags & BBR_RWND_COLLAPSED) == 0)) { 4998 /* 4999 * If the rwnd collapsed on 5000 * the one we are retransmitting 5001 * it does not count against the 5002 * rxt count. 5003 */ 5004 tp->t_rxtshift++; 5005 } 5006 if (tp->t_rxtshift > TCP_MAXRXTSHIFT) { 5007 tp->t_rxtshift = TCP_MAXRXTSHIFT; 5008 KMOD_TCPSTAT_INC(tcps_timeoutdrop); 5009 retval = 1; 5010 tcp_log_end_status(tp, TCP_EI_STATUS_RETRAN); 5011 tcp_set_inp_to_drop(bbr->rc_inp, 5012 (tp->t_softerror ? (uint16_t) tp->t_softerror : ETIMEDOUT)); 5013 goto out; 5014 } 5015 if (tp->t_state == TCPS_SYN_SENT) { 5016 /* 5017 * If the SYN was retransmitted, indicate CWND to be limited 5018 * to 1 segment in cc_conn_init(). 5019 */ 5020 tp->snd_cwnd = 1; 5021 } else if (tp->t_rxtshift == 1) { 5022 /* 5023 * first retransmit; record ssthresh and cwnd so they can be 5024 * recovered if this turns out to be a "bad" retransmit. A 5025 * retransmit is considered "bad" if an ACK for this segment 5026 * is received within RTT/2 interval; the assumption here is 5027 * that the ACK was already in flight. See "On Estimating 5028 * End-to-End Network Path Properties" by Allman and Paxson 5029 * for more details. 5030 */ 5031 tp->snd_cwnd = tp->t_maxseg - bbr->rc_last_options; 5032 if (!IN_RECOVERY(tp->t_flags)) { 5033 tp->snd_cwnd_prev = tp->snd_cwnd; 5034 tp->snd_ssthresh_prev = tp->snd_ssthresh; 5035 tp->snd_recover_prev = tp->snd_recover; 5036 tp->t_badrxtwin = ticks + (tp->t_srtt >> (TCP_RTT_SHIFT + 1)); 5037 tp->t_flags |= TF_PREVVALID; 5038 } else { 5039 tp->t_flags &= ~TF_PREVVALID; 5040 } 5041 tp->snd_cwnd = tp->t_maxseg - bbr->rc_last_options; 5042 } else { 5043 tp->snd_cwnd = tp->t_maxseg - bbr->rc_last_options; 5044 tp->t_flags &= ~TF_PREVVALID; 5045 } 5046 KMOD_TCPSTAT_INC(tcps_rexmttimeo); 5047 if ((tp->t_state == TCPS_SYN_SENT) || 5048 (tp->t_state == TCPS_SYN_RECEIVED)) 5049 rexmt = USEC_2_TICKS(BBR_INITIAL_RTO) * tcp_backoff[tp->t_rxtshift]; 5050 else 5051 rexmt = TCP_REXMTVAL(tp) * tcp_backoff[tp->t_rxtshift]; 5052 TCPT_RANGESET(tp->t_rxtcur, rexmt, 5053 MSEC_2_TICKS(bbr->r_ctl.rc_min_rto_ms), 5054 MSEC_2_TICKS(((uint32_t)bbr->rc_max_rto_sec) * 1000)); 5055 /* 5056 * We enter the path for PLMTUD if connection is established or, if 5057 * connection is FIN_WAIT_1 status, reason for the last is that if 5058 * amount of data we send is very small, we could send it in couple 5059 * of packets and process straight to FIN. In that case we won't 5060 * catch ESTABLISHED state. 5061 */ 5062 #ifdef INET6 5063 isipv6 = (tp->t_inpcb->inp_vflag & INP_IPV6) ? true : false; 5064 #else 5065 isipv6 = false; 5066 #endif 5067 if (((V_tcp_pmtud_blackhole_detect == 1) || 5068 (V_tcp_pmtud_blackhole_detect == 2 && !isipv6) || 5069 (V_tcp_pmtud_blackhole_detect == 3 && isipv6)) && 5070 ((tp->t_state == TCPS_ESTABLISHED) || 5071 (tp->t_state == TCPS_FIN_WAIT_1))) { 5072 /* 5073 * Idea here is that at each stage of mtu probe (usually, 5074 * 1448 -> 1188 -> 524) should be given 2 chances to recover 5075 * before further clamping down. 'tp->t_rxtshift % 2 == 0' 5076 * should take care of that. 5077 */ 5078 if (((tp->t_flags2 & (TF2_PLPMTU_PMTUD | TF2_PLPMTU_MAXSEGSNT)) == 5079 (TF2_PLPMTU_PMTUD | TF2_PLPMTU_MAXSEGSNT)) && 5080 (tp->t_rxtshift >= 2 && tp->t_rxtshift < 6 && 5081 tp->t_rxtshift % 2 == 0)) { 5082 /* 5083 * Enter Path MTU Black-hole Detection mechanism: - 5084 * Disable Path MTU Discovery (IP "DF" bit). - 5085 * Reduce MTU to lower value than what we negotiated 5086 * with peer. 5087 */ 5088 if ((tp->t_flags2 & TF2_PLPMTU_BLACKHOLE) == 0) { 5089 /* 5090 * Record that we may have found a black 5091 * hole. 5092 */ 5093 tp->t_flags2 |= TF2_PLPMTU_BLACKHOLE; 5094 /* Keep track of previous MSS. */ 5095 tp->t_pmtud_saved_maxseg = tp->t_maxseg; 5096 } 5097 /* 5098 * Reduce the MSS to blackhole value or to the 5099 * default in an attempt to retransmit. 5100 */ 5101 #ifdef INET6 5102 isipv6 = bbr->r_is_v6; 5103 if (isipv6 && 5104 tp->t_maxseg > V_tcp_v6pmtud_blackhole_mss) { 5105 /* Use the sysctl tuneable blackhole MSS. */ 5106 tp->t_maxseg = V_tcp_v6pmtud_blackhole_mss; 5107 KMOD_TCPSTAT_INC(tcps_pmtud_blackhole_activated); 5108 } else if (isipv6) { 5109 /* Use the default MSS. */ 5110 tp->t_maxseg = V_tcp_v6mssdflt; 5111 /* 5112 * Disable Path MTU Discovery when we switch 5113 * to minmss. 5114 */ 5115 tp->t_flags2 &= ~TF2_PLPMTU_PMTUD; 5116 KMOD_TCPSTAT_INC(tcps_pmtud_blackhole_activated_min_mss); 5117 } 5118 #endif 5119 #if defined(INET6) && defined(INET) 5120 else 5121 #endif 5122 #ifdef INET 5123 if (tp->t_maxseg > V_tcp_pmtud_blackhole_mss) { 5124 /* Use the sysctl tuneable blackhole MSS. */ 5125 tp->t_maxseg = V_tcp_pmtud_blackhole_mss; 5126 KMOD_TCPSTAT_INC(tcps_pmtud_blackhole_activated); 5127 } else { 5128 /* Use the default MSS. */ 5129 tp->t_maxseg = V_tcp_mssdflt; 5130 /* 5131 * Disable Path MTU Discovery when we switch 5132 * to minmss. 5133 */ 5134 tp->t_flags2 &= ~TF2_PLPMTU_PMTUD; 5135 KMOD_TCPSTAT_INC(tcps_pmtud_blackhole_activated_min_mss); 5136 } 5137 #endif 5138 } else { 5139 /* 5140 * If further retransmissions are still unsuccessful 5141 * with a lowered MTU, maybe this isn't a blackhole 5142 * and we restore the previous MSS and blackhole 5143 * detection flags. The limit '6' is determined by 5144 * giving each probe stage (1448, 1188, 524) 2 5145 * chances to recover. 5146 */ 5147 if ((tp->t_flags2 & TF2_PLPMTU_BLACKHOLE) && 5148 (tp->t_rxtshift >= 6)) { 5149 tp->t_flags2 |= TF2_PLPMTU_PMTUD; 5150 tp->t_flags2 &= ~TF2_PLPMTU_BLACKHOLE; 5151 tp->t_maxseg = tp->t_pmtud_saved_maxseg; 5152 KMOD_TCPSTAT_INC(tcps_pmtud_blackhole_failed); 5153 } 5154 } 5155 } 5156 /* 5157 * Disable RFC1323 and SACK if we haven't got any response to our 5158 * third SYN to work-around some broken terminal servers (most of 5159 * which have hopefully been retired) that have bad VJ header 5160 * compression code which trashes TCP segments containing 5161 * unknown-to-them TCP options. 5162 */ 5163 if (tcp_rexmit_drop_options && (tp->t_state == TCPS_SYN_SENT) && 5164 (tp->t_rxtshift == 3)) 5165 tp->t_flags &= ~(TF_REQ_SCALE | TF_REQ_TSTMP | TF_SACK_PERMIT); 5166 /* 5167 * If we backed off this far, our srtt estimate is probably bogus. 5168 * Clobber it so we'll take the next rtt measurement as our srtt; 5169 * move the current srtt into rttvar to keep the current retransmit 5170 * times until then. 5171 */ 5172 if (tp->t_rxtshift > TCP_MAXRXTSHIFT / 4) { 5173 #ifdef INET6 5174 if (bbr->r_is_v6) 5175 in6_losing(tp->t_inpcb); 5176 else 5177 #endif 5178 in_losing(tp->t_inpcb); 5179 tp->t_rttvar += (tp->t_srtt >> TCP_RTT_SHIFT); 5180 tp->t_srtt = 0; 5181 } 5182 sack_filter_clear(&bbr->r_ctl.bbr_sf, tp->snd_una); 5183 tp->snd_recover = tp->snd_max; 5184 tp->t_flags |= TF_ACKNOW; 5185 tp->t_rtttime = 0; 5186 out: 5187 return (retval); 5188 } 5189 5190 static int 5191 bbr_process_timers(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts, uint8_t hpts_calling) 5192 { 5193 int32_t ret = 0; 5194 int32_t timers = (bbr->r_ctl.rc_hpts_flags & PACE_TMR_MASK); 5195 5196 if (timers == 0) { 5197 return (0); 5198 } 5199 if (tp->t_state == TCPS_LISTEN) { 5200 /* no timers on listen sockets */ 5201 if (bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) 5202 return (0); 5203 return (1); 5204 } 5205 if (TSTMP_LT(cts, bbr->r_ctl.rc_timer_exp)) { 5206 uint32_t left; 5207 5208 if (bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) { 5209 ret = -1; 5210 bbr_log_to_processing(bbr, cts, ret, 0, hpts_calling); 5211 return (0); 5212 } 5213 if (hpts_calling == 0) { 5214 ret = -2; 5215 bbr_log_to_processing(bbr, cts, ret, 0, hpts_calling); 5216 return (0); 5217 } 5218 /* 5219 * Ok our timer went off early and we are not paced false 5220 * alarm, go back to sleep. 5221 */ 5222 left = bbr->r_ctl.rc_timer_exp - cts; 5223 ret = -3; 5224 bbr_log_to_processing(bbr, cts, ret, left, hpts_calling); 5225 tcp_hpts_insert(tp->t_inpcb, HPTS_USEC_TO_SLOTS(left)); 5226 return (1); 5227 } 5228 bbr->rc_tmr_stopped = 0; 5229 bbr->r_ctl.rc_hpts_flags &= ~PACE_TMR_MASK; 5230 if (timers & PACE_TMR_DELACK) { 5231 ret = bbr_timeout_delack(tp, bbr, cts); 5232 } else if (timers & PACE_TMR_PERSIT) { 5233 ret = bbr_timeout_persist(tp, bbr, cts); 5234 } else if (timers & PACE_TMR_RACK) { 5235 bbr->r_ctl.rc_tlp_rxt_last_time = cts; 5236 ret = bbr_timeout_rack(tp, bbr, cts); 5237 } else if (timers & PACE_TMR_TLP) { 5238 bbr->r_ctl.rc_tlp_rxt_last_time = cts; 5239 ret = bbr_timeout_tlp(tp, bbr, cts); 5240 } else if (timers & PACE_TMR_RXT) { 5241 bbr->r_ctl.rc_tlp_rxt_last_time = cts; 5242 ret = bbr_timeout_rxt(tp, bbr, cts); 5243 } else if (timers & PACE_TMR_KEEP) { 5244 ret = bbr_timeout_keepalive(tp, bbr, cts); 5245 } 5246 bbr_log_to_processing(bbr, cts, ret, timers, hpts_calling); 5247 return (ret); 5248 } 5249 5250 static void 5251 bbr_timer_cancel(struct tcp_bbr *bbr, int32_t line, uint32_t cts) 5252 { 5253 if (bbr->r_ctl.rc_hpts_flags & PACE_TMR_MASK) { 5254 uint8_t hpts_removed = 0; 5255 5256 if (bbr->rc_inp->inp_in_hpts && 5257 (bbr->rc_timer_first == 1)) { 5258 /* 5259 * If we are canceling timer's when we have the 5260 * timer ahead of the output being paced. We also 5261 * must remove ourselves from the hpts. 5262 */ 5263 hpts_removed = 1; 5264 tcp_hpts_remove(bbr->rc_inp, HPTS_REMOVE_OUTPUT); 5265 if (bbr->r_ctl.rc_last_delay_val) { 5266 /* Update the last hptsi delay too */ 5267 uint32_t time_since_send; 5268 5269 if (TSTMP_GT(cts, bbr->rc_pacer_started)) 5270 time_since_send = cts - bbr->rc_pacer_started; 5271 else 5272 time_since_send = 0; 5273 if (bbr->r_ctl.rc_last_delay_val > time_since_send) { 5274 /* Cut down our slot time */ 5275 bbr->r_ctl.rc_last_delay_val -= time_since_send; 5276 } else { 5277 bbr->r_ctl.rc_last_delay_val = 0; 5278 } 5279 bbr->rc_pacer_started = cts; 5280 } 5281 } 5282 bbr->rc_timer_first = 0; 5283 bbr_log_to_cancel(bbr, line, cts, hpts_removed); 5284 bbr->rc_tmr_stopped = bbr->r_ctl.rc_hpts_flags & PACE_TMR_MASK; 5285 bbr->r_ctl.rc_hpts_flags &= ~(PACE_TMR_MASK); 5286 } 5287 } 5288 5289 static void 5290 bbr_timer_stop(struct tcpcb *tp, uint32_t timer_type) 5291 { 5292 struct tcp_bbr *bbr; 5293 5294 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 5295 bbr->rc_all_timers_stopped = 1; 5296 return; 5297 } 5298 5299 /* 5300 * stop all timers always returning 0. 5301 */ 5302 static int 5303 bbr_stopall(struct tcpcb *tp) 5304 { 5305 return (0); 5306 } 5307 5308 static void 5309 bbr_timer_activate(struct tcpcb *tp, uint32_t timer_type, uint32_t delta) 5310 { 5311 return; 5312 } 5313 5314 /* 5315 * return true if a bbr timer (rack or tlp) is active. 5316 */ 5317 static int 5318 bbr_timer_active(struct tcpcb *tp, uint32_t timer_type) 5319 { 5320 return (0); 5321 } 5322 5323 static uint32_t 5324 bbr_get_earliest_send_outstanding(struct tcp_bbr *bbr, struct bbr_sendmap *u_rsm, uint32_t cts) 5325 { 5326 struct bbr_sendmap *rsm; 5327 5328 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_tmap); 5329 if ((rsm == NULL) || (u_rsm == rsm)) 5330 return (cts); 5331 return(rsm->r_tim_lastsent[(rsm->r_rtr_cnt-1)]); 5332 } 5333 5334 static void 5335 bbr_update_rsm(struct tcpcb *tp, struct tcp_bbr *bbr, 5336 struct bbr_sendmap *rsm, uint32_t cts, uint32_t pacing_time) 5337 { 5338 int32_t idx; 5339 5340 rsm->r_rtr_cnt++; 5341 rsm->r_dupack = 0; 5342 if (rsm->r_rtr_cnt > BBR_NUM_OF_RETRANS) { 5343 rsm->r_rtr_cnt = BBR_NUM_OF_RETRANS; 5344 rsm->r_flags |= BBR_OVERMAX; 5345 } 5346 if (rsm->r_flags & BBR_RWND_COLLAPSED) { 5347 /* Take off the collapsed flag at rxt */ 5348 rsm->r_flags &= ~BBR_RWND_COLLAPSED; 5349 } 5350 if (rsm->r_flags & BBR_MARKED_LOST) { 5351 /* We have retransmitted, its no longer lost */ 5352 rsm->r_flags &= ~BBR_MARKED_LOST; 5353 bbr->r_ctl.rc_lost_bytes -= rsm->r_end - rsm->r_start; 5354 } 5355 if (rsm->r_flags & BBR_RXT_CLEARED) { 5356 /* 5357 * We hit a RXT timer on it and 5358 * we cleared the "acked" flag. 5359 * We now have it going back into 5360 * flight, we can remove the cleared 5361 * flag and possibly do accounting on 5362 * this piece. 5363 */ 5364 rsm->r_flags &= ~BBR_RXT_CLEARED; 5365 } 5366 if ((rsm->r_rtr_cnt > 1) && ((rsm->r_flags & BBR_TLP) == 0)) { 5367 bbr->r_ctl.rc_holes_rxt += (rsm->r_end - rsm->r_start); 5368 rsm->r_rtr_bytes += (rsm->r_end - rsm->r_start); 5369 } 5370 idx = rsm->r_rtr_cnt - 1; 5371 rsm->r_tim_lastsent[idx] = cts; 5372 rsm->r_pacing_delay = pacing_time; 5373 rsm->r_delivered = bbr->r_ctl.rc_delivered; 5374 rsm->r_ts_valid = bbr->rc_ts_valid; 5375 if (bbr->rc_ts_valid) 5376 rsm->r_del_ack_ts = bbr->r_ctl.last_inbound_ts; 5377 if (bbr->r_ctl.r_app_limited_until) 5378 rsm->r_app_limited = 1; 5379 else 5380 rsm->r_app_limited = 0; 5381 if (bbr->rc_bbr_state == BBR_STATE_PROBE_BW) 5382 rsm->r_bbr_state = bbr_state_val(bbr); 5383 else 5384 rsm->r_bbr_state = 8; 5385 if (rsm->r_flags & BBR_ACKED) { 5386 /* Problably MTU discovery messing with us */ 5387 uint32_t old_flags; 5388 5389 old_flags = rsm->r_flags; 5390 rsm->r_flags &= ~BBR_ACKED; 5391 bbr_log_type_rsmclear(bbr, cts, rsm, old_flags, __LINE__); 5392 bbr->r_ctl.rc_sacked -= (rsm->r_end - rsm->r_start); 5393 if (bbr->r_ctl.rc_sacked == 0) 5394 bbr->r_ctl.rc_sacklast = NULL; 5395 } 5396 if (rsm->r_in_tmap) { 5397 TAILQ_REMOVE(&bbr->r_ctl.rc_tmap, rsm, r_tnext); 5398 } 5399 TAILQ_INSERT_TAIL(&bbr->r_ctl.rc_tmap, rsm, r_tnext); 5400 rsm->r_in_tmap = 1; 5401 if (rsm->r_flags & BBR_SACK_PASSED) { 5402 /* We have retransmitted due to the SACK pass */ 5403 rsm->r_flags &= ~BBR_SACK_PASSED; 5404 rsm->r_flags |= BBR_WAS_SACKPASS; 5405 } 5406 rsm->r_first_sent_time = bbr_get_earliest_send_outstanding(bbr, rsm, cts); 5407 rsm->r_flight_at_send = ctf_flight_size(bbr->rc_tp, 5408 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 5409 bbr->r_ctl.rc_next = TAILQ_NEXT(rsm, r_next); 5410 if (bbr->r_ctl.rc_bbr_hptsi_gain > BBR_UNIT) { 5411 rsm->r_is_gain = 1; 5412 rsm->r_is_drain = 0; 5413 } else if (bbr->r_ctl.rc_bbr_hptsi_gain < BBR_UNIT) { 5414 rsm->r_is_drain = 1; 5415 rsm->r_is_gain = 0; 5416 } else { 5417 rsm->r_is_drain = 0; 5418 rsm->r_is_gain = 0; 5419 } 5420 rsm->r_del_time = bbr->r_ctl.rc_del_time; /* TEMP GOOGLE CODE */ 5421 } 5422 5423 /* 5424 * Returns 0, or the sequence where we stopped 5425 * updating. We also update the lenp to be the amount 5426 * of data left. 5427 */ 5428 5429 static uint32_t 5430 bbr_update_entry(struct tcpcb *tp, struct tcp_bbr *bbr, 5431 struct bbr_sendmap *rsm, uint32_t cts, int32_t *lenp, uint32_t pacing_time) 5432 { 5433 /* 5434 * We (re-)transmitted starting at rsm->r_start for some length 5435 * (possibly less than r_end. 5436 */ 5437 struct bbr_sendmap *nrsm; 5438 uint32_t c_end; 5439 int32_t len; 5440 5441 len = *lenp; 5442 c_end = rsm->r_start + len; 5443 if (SEQ_GEQ(c_end, rsm->r_end)) { 5444 /* 5445 * We retransmitted the whole piece or more than the whole 5446 * slopping into the next rsm. 5447 */ 5448 bbr_update_rsm(tp, bbr, rsm, cts, pacing_time); 5449 if (c_end == rsm->r_end) { 5450 *lenp = 0; 5451 return (0); 5452 } else { 5453 int32_t act_len; 5454 5455 /* Hangs over the end return whats left */ 5456 act_len = rsm->r_end - rsm->r_start; 5457 *lenp = (len - act_len); 5458 return (rsm->r_end); 5459 } 5460 /* We don't get out of this block. */ 5461 } 5462 /* 5463 * Here we retransmitted less than the whole thing which means we 5464 * have to split this into what was transmitted and what was not. 5465 */ 5466 nrsm = bbr_alloc_full_limit(bbr); 5467 if (nrsm == NULL) { 5468 *lenp = 0; 5469 return (0); 5470 } 5471 /* 5472 * So here we are going to take the original rsm and make it what we 5473 * retransmitted. nrsm will be the tail portion we did not 5474 * retransmit. For example say the chunk was 1, 11 (10 bytes). And 5475 * we retransmitted 5 bytes i.e. 1, 5. The original piece shrinks to 5476 * 1, 6 and the new piece will be 6, 11. 5477 */ 5478 bbr_clone_rsm(bbr, nrsm, rsm, c_end); 5479 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_map, rsm, nrsm, r_next); 5480 nrsm->r_dupack = 0; 5481 if (rsm->r_in_tmap) { 5482 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, rsm, nrsm, r_tnext); 5483 nrsm->r_in_tmap = 1; 5484 } 5485 rsm->r_flags &= (~BBR_HAS_FIN); 5486 bbr_update_rsm(tp, bbr, rsm, cts, pacing_time); 5487 *lenp = 0; 5488 return (0); 5489 } 5490 5491 static uint64_t 5492 bbr_get_hardware_rate(struct tcp_bbr *bbr) 5493 { 5494 uint64_t bw; 5495 5496 bw = bbr_get_bw(bbr); 5497 bw *= (uint64_t)bbr_hptsi_gain[BBR_SUB_GAIN]; 5498 bw /= (uint64_t)BBR_UNIT; 5499 return(bw); 5500 } 5501 5502 static void 5503 bbr_setup_less_of_rate(struct tcp_bbr *bbr, uint32_t cts, 5504 uint64_t act_rate, uint64_t rate_wanted) 5505 { 5506 /* 5507 * We could not get a full gains worth 5508 * of rate. 5509 */ 5510 if (get_filter_value(&bbr->r_ctl.rc_delrate) >= act_rate) { 5511 /* we can't even get the real rate */ 5512 uint64_t red; 5513 5514 bbr->skip_gain = 1; 5515 bbr->gain_is_limited = 0; 5516 red = get_filter_value(&bbr->r_ctl.rc_delrate) - act_rate; 5517 if (red) 5518 filter_reduce_by(&bbr->r_ctl.rc_delrate, red, cts); 5519 } else { 5520 /* We can use a lower gain */ 5521 bbr->skip_gain = 0; 5522 bbr->gain_is_limited = 1; 5523 } 5524 } 5525 5526 static void 5527 bbr_update_hardware_pacing_rate(struct tcp_bbr *bbr, uint32_t cts) 5528 { 5529 const struct tcp_hwrate_limit_table *nrte; 5530 int error, rate = -1; 5531 5532 if (bbr->r_ctl.crte == NULL) 5533 return; 5534 if ((bbr->rc_inp->inp_route.ro_nh == NULL) || 5535 (bbr->rc_inp->inp_route.ro_nh->nh_ifp == NULL)) { 5536 /* Lost our routes? */ 5537 /* Clear the way for a re-attempt */ 5538 bbr->bbr_attempt_hdwr_pace = 0; 5539 lost_rate: 5540 bbr->gain_is_limited = 0; 5541 bbr->skip_gain = 0; 5542 bbr->bbr_hdrw_pacing = 0; 5543 counter_u64_add(bbr_flows_whdwr_pacing, -1); 5544 counter_u64_add(bbr_flows_nohdwr_pacing, 1); 5545 tcp_bbr_tso_size_check(bbr, cts); 5546 return; 5547 } 5548 rate = bbr_get_hardware_rate(bbr); 5549 nrte = tcp_chg_pacing_rate(bbr->r_ctl.crte, 5550 bbr->rc_tp, 5551 bbr->rc_inp->inp_route.ro_nh->nh_ifp, 5552 rate, 5553 (RS_PACING_GEQ|RS_PACING_SUB_OK), 5554 &error); 5555 if (nrte == NULL) { 5556 goto lost_rate; 5557 } 5558 if (nrte != bbr->r_ctl.crte) { 5559 bbr->r_ctl.crte = nrte; 5560 if (error == 0) { 5561 BBR_STAT_INC(bbr_hdwr_rl_mod_ok); 5562 if (bbr->r_ctl.crte->rate < rate) { 5563 /* We have a problem */ 5564 bbr_setup_less_of_rate(bbr, cts, 5565 bbr->r_ctl.crte->rate, rate); 5566 } else { 5567 /* We are good */ 5568 bbr->gain_is_limited = 0; 5569 bbr->skip_gain = 0; 5570 } 5571 } else { 5572 /* A failure should release the tag */ 5573 BBR_STAT_INC(bbr_hdwr_rl_mod_fail); 5574 bbr->gain_is_limited = 0; 5575 bbr->skip_gain = 0; 5576 bbr->bbr_hdrw_pacing = 0; 5577 } 5578 bbr_type_log_hdwr_pacing(bbr, 5579 bbr->r_ctl.crte->ptbl->rs_ifp, 5580 rate, 5581 ((bbr->r_ctl.crte == NULL) ? 0 : bbr->r_ctl.crte->rate), 5582 __LINE__, 5583 cts, 5584 error); 5585 } 5586 } 5587 5588 static void 5589 bbr_adjust_for_hw_pacing(struct tcp_bbr *bbr, uint32_t cts) 5590 { 5591 /* 5592 * If we have hardware pacing support 5593 * we need to factor that in for our 5594 * TSO size. 5595 */ 5596 const struct tcp_hwrate_limit_table *rlp; 5597 uint32_t cur_delay, seg_sz, maxseg, new_tso, delta, hdwr_delay; 5598 5599 if ((bbr->bbr_hdrw_pacing == 0) || 5600 (IN_RECOVERY(bbr->rc_tp->t_flags)) || 5601 (bbr->r_ctl.crte == NULL)) 5602 return; 5603 if (bbr->hw_pacing_set == 0) { 5604 /* Not yet by the hdwr pacing count delay */ 5605 return; 5606 } 5607 if (bbr_hdwr_pace_adjust == 0) { 5608 /* No adjustment */ 5609 return; 5610 } 5611 rlp = bbr->r_ctl.crte; 5612 if (bbr->rc_tp->t_maxseg > bbr->rc_last_options) 5613 maxseg = bbr->rc_tp->t_maxseg - bbr->rc_last_options; 5614 else 5615 maxseg = BBR_MIN_SEG - bbr->rc_last_options; 5616 /* 5617 * So lets first get the 5618 * time we will take between 5619 * TSO sized sends currently without 5620 * hardware help. 5621 */ 5622 cur_delay = bbr_get_pacing_delay(bbr, BBR_UNIT, 5623 bbr->r_ctl.rc_pace_max_segs, cts, 1); 5624 hdwr_delay = bbr->r_ctl.rc_pace_max_segs / maxseg; 5625 hdwr_delay *= rlp->time_between; 5626 if (cur_delay > hdwr_delay) 5627 delta = cur_delay - hdwr_delay; 5628 else 5629 delta = 0; 5630 bbr_log_type_tsosize(bbr, cts, delta, cur_delay, hdwr_delay, 5631 (bbr->r_ctl.rc_pace_max_segs / maxseg), 5632 1); 5633 if (delta && 5634 (delta < (max(rlp->time_between, 5635 bbr->r_ctl.bbr_hptsi_segments_delay_tar)))) { 5636 /* 5637 * Now lets divide by the pacing 5638 * time between each segment the 5639 * hardware sends rounding up and 5640 * derive a bytes from that. We multiply 5641 * that by bbr_hdwr_pace_adjust to get 5642 * more bang for our buck. 5643 * 5644 * The goal is to have the software pacer 5645 * waiting no more than an additional 5646 * pacing delay if we can (without the 5647 * compensation i.e. x bbr_hdwr_pace_adjust). 5648 */ 5649 seg_sz = max(((cur_delay + rlp->time_between)/rlp->time_between), 5650 (bbr->r_ctl.rc_pace_max_segs/maxseg)); 5651 seg_sz *= bbr_hdwr_pace_adjust; 5652 if (bbr_hdwr_pace_floor && 5653 (seg_sz < bbr->r_ctl.crte->ptbl->rs_min_seg)) { 5654 /* Currently hardware paces 5655 * out rs_min_seg segments at a time. 5656 * We need to make sure we always send at least 5657 * a full burst of bbr_hdwr_pace_floor down. 5658 */ 5659 seg_sz = bbr->r_ctl.crte->ptbl->rs_min_seg; 5660 } 5661 seg_sz *= maxseg; 5662 } else if (delta == 0) { 5663 /* 5664 * The highest pacing rate is 5665 * above our b/w gained. This means 5666 * we probably are going quite fast at 5667 * the hardware highest rate. Lets just multiply 5668 * the calculated TSO size by the 5669 * multiplier factor (its probably 5670 * 4 segments in the default config for 5671 * mlx). 5672 */ 5673 seg_sz = bbr->r_ctl.rc_pace_max_segs * bbr_hdwr_pace_adjust; 5674 if (bbr_hdwr_pace_floor && 5675 (seg_sz < bbr->r_ctl.crte->ptbl->rs_min_seg)) { 5676 /* Currently hardware paces 5677 * out rs_min_seg segments at a time. 5678 * We need to make sure we always send at least 5679 * a full burst of bbr_hdwr_pace_floor down. 5680 */ 5681 seg_sz = bbr->r_ctl.crte->ptbl->rs_min_seg; 5682 } 5683 } else { 5684 /* 5685 * The pacing time difference is so 5686 * big that the hardware will 5687 * pace out more rapidly then we 5688 * really want and then we 5689 * will have a long delay. Lets just keep 5690 * the same TSO size so its as if 5691 * we were not using hdwr pacing (we 5692 * just gain a bit of spacing from the 5693 * hardware if seg_sz > 1). 5694 */ 5695 seg_sz = bbr->r_ctl.rc_pace_max_segs; 5696 } 5697 if (seg_sz > bbr->r_ctl.rc_pace_max_segs) 5698 new_tso = seg_sz; 5699 else 5700 new_tso = bbr->r_ctl.rc_pace_max_segs; 5701 if (new_tso >= (PACE_MAX_IP_BYTES-maxseg)) 5702 new_tso = PACE_MAX_IP_BYTES - maxseg; 5703 5704 if (new_tso != bbr->r_ctl.rc_pace_max_segs) { 5705 bbr_log_type_tsosize(bbr, cts, new_tso, 0, bbr->r_ctl.rc_pace_max_segs, maxseg, 0); 5706 bbr->r_ctl.rc_pace_max_segs = new_tso; 5707 } 5708 } 5709 5710 static void 5711 tcp_bbr_tso_size_check(struct tcp_bbr *bbr, uint32_t cts) 5712 { 5713 uint64_t bw; 5714 uint32_t old_tso = 0, new_tso; 5715 uint32_t maxseg, bytes; 5716 uint32_t tls_seg=0; 5717 /* 5718 * Google/linux uses the following algorithm to determine 5719 * the TSO size based on the b/w of the link (from Neal Cardwell email 9/27/18): 5720 * 5721 * bytes = bw_in_bytes_per_second / 1000 5722 * bytes = min(bytes, 64k) 5723 * tso_segs = bytes / MSS 5724 * if (bw < 1.2Mbs) 5725 * min_tso_segs = 1 5726 * else 5727 * min_tso_segs = 2 5728 * tso_segs = max(tso_segs, min_tso_segs) 5729 * 5730 * * Note apply a device specific limit (we apply this in the 5731 * tcp_m_copym). 5732 * Note that before the initial measurement is made google bursts out 5733 * a full iwnd just like new-reno/cubic. 5734 * 5735 * We do not use this algorithm. Instead we 5736 * use a two phased approach: 5737 * 5738 * if ( bw <= per-tcb-cross-over) 5739 * goal_tso = calculate how much with this bw we 5740 * can send in goal-time seconds. 5741 * if (goal_tso > mss) 5742 * seg = goal_tso / mss 5743 * tso = seg * mss 5744 * else 5745 * tso = mss 5746 * if (tso > per-tcb-max) 5747 * tso = per-tcb-max 5748 * else if ( bw > 512Mbps) 5749 * tso = max-tso (64k/mss) 5750 * else 5751 * goal_tso = bw / per-tcb-divsor 5752 * seg = (goal_tso + mss-1)/mss 5753 * tso = seg * mss 5754 * 5755 * if (tso < per-tcb-floor) 5756 * tso = per-tcb-floor 5757 * if (tso > per-tcb-utter_max) 5758 * tso = per-tcb-utter_max 5759 * 5760 * Note the default per-tcb-divisor is 1000 (same as google). 5761 * the goal cross over is 30Mbps however. To recreate googles 5762 * algorithm you need to set: 5763 * 5764 * cross-over = 23,168,000 bps 5765 * goal-time = 18000 5766 * per-tcb-max = 2 5767 * per-tcb-divisor = 1000 5768 * per-tcb-floor = 1 5769 * 5770 * This will get you "google bbr" behavior with respect to tso size. 5771 * 5772 * Note we do set anything TSO size until we are past the initial 5773 * window. Before that we gnerally use either a single MSS 5774 * or we use the full IW size (so we burst a IW at a time) 5775 */ 5776 5777 if (bbr->rc_tp->t_maxseg > bbr->rc_last_options) { 5778 maxseg = bbr->rc_tp->t_maxseg - bbr->rc_last_options; 5779 } else { 5780 maxseg = BBR_MIN_SEG - bbr->rc_last_options; 5781 } 5782 old_tso = bbr->r_ctl.rc_pace_max_segs; 5783 if (bbr->rc_past_init_win == 0) { 5784 /* 5785 * Not enough data has been acknowledged to make a 5786 * judgement. Set up the initial TSO based on if we 5787 * are sending a full IW at once or not. 5788 */ 5789 if (bbr->rc_use_google) 5790 bbr->r_ctl.rc_pace_max_segs = ((bbr->rc_tp->t_maxseg - bbr->rc_last_options) * 2); 5791 else if (bbr->bbr_init_win_cheat) 5792 bbr->r_ctl.rc_pace_max_segs = bbr_initial_cwnd(bbr, bbr->rc_tp); 5793 else 5794 bbr->r_ctl.rc_pace_max_segs = bbr->rc_tp->t_maxseg - bbr->rc_last_options; 5795 if (bbr->r_ctl.rc_pace_min_segs != bbr->rc_tp->t_maxseg) 5796 bbr->r_ctl.rc_pace_min_segs = bbr->rc_tp->t_maxseg; 5797 if (bbr->r_ctl.rc_pace_max_segs == 0) { 5798 bbr->r_ctl.rc_pace_max_segs = maxseg; 5799 } 5800 bbr_log_type_tsosize(bbr, cts, bbr->r_ctl.rc_pace_max_segs, tls_seg, old_tso, maxseg, 0); 5801 bbr_adjust_for_hw_pacing(bbr, cts); 5802 return; 5803 } 5804 /** 5805 * Now lets set the TSO goal based on our delivery rate in 5806 * bytes per second. Note we only do this if 5807 * we have acked at least the initial cwnd worth of data. 5808 */ 5809 bw = bbr_get_bw(bbr); 5810 if (IN_RECOVERY(bbr->rc_tp->t_flags) && 5811 (bbr->rc_use_google == 0)) { 5812 /* We clamp to one MSS in recovery */ 5813 new_tso = maxseg; 5814 } else if (bbr->rc_use_google) { 5815 int min_tso_segs; 5816 5817 /* Google considers the gain too */ 5818 if (bbr->r_ctl.rc_bbr_hptsi_gain != BBR_UNIT) { 5819 bw *= bbr->r_ctl.rc_bbr_hptsi_gain; 5820 bw /= BBR_UNIT; 5821 } 5822 bytes = bw / 1024; 5823 if (bytes > (64 * 1024)) 5824 bytes = 64 * 1024; 5825 new_tso = bytes / maxseg; 5826 if (bw < ONE_POINT_TWO_MEG) 5827 min_tso_segs = 1; 5828 else 5829 min_tso_segs = 2; 5830 if (new_tso < min_tso_segs) 5831 new_tso = min_tso_segs; 5832 new_tso *= maxseg; 5833 } else if (bbr->rc_no_pacing) { 5834 new_tso = (PACE_MAX_IP_BYTES / maxseg) * maxseg; 5835 } else if (bw <= bbr->r_ctl.bbr_cross_over) { 5836 /* 5837 * Calculate the worse case b/w TSO if we are inserting no 5838 * more than a delay_target number of TSO's. 5839 */ 5840 uint32_t tso_len, min_tso; 5841 5842 tso_len = bbr_get_pacing_length(bbr, BBR_UNIT, bbr->r_ctl.bbr_hptsi_segments_delay_tar, bw); 5843 if (tso_len > maxseg) { 5844 new_tso = tso_len / maxseg; 5845 if (new_tso > bbr->r_ctl.bbr_hptsi_segments_max) 5846 new_tso = bbr->r_ctl.bbr_hptsi_segments_max; 5847 new_tso *= maxseg; 5848 } else { 5849 /* 5850 * less than a full sized frame yikes.. long rtt or 5851 * low bw? 5852 */ 5853 min_tso = bbr_minseg(bbr); 5854 if ((tso_len > min_tso) && (bbr_all_get_min == 0)) 5855 new_tso = rounddown(tso_len, min_tso); 5856 else 5857 new_tso = min_tso; 5858 } 5859 } else if (bw > FIVETWELVE_MBPS) { 5860 /* 5861 * This guy is so fast b/w wise that we can TSO as large as 5862 * possible of segments that the NIC will allow. 5863 */ 5864 new_tso = rounddown(PACE_MAX_IP_BYTES, maxseg); 5865 } else { 5866 /* 5867 * This formula is based on attempting to send a segment or 5868 * more every bbr_hptsi_per_second. The default is 1000 5869 * which means you are targeting what you can send every 1ms 5870 * based on the peers bw. 5871 * 5872 * If the number drops to say 500, then you are looking more 5873 * at 2ms and you will raise how much we send in a single 5874 * TSO thus saving CPU (less bbr_output_wtime() calls). The 5875 * trade off of course is you will send more at once and 5876 * thus tend to clump up the sends into larger "bursts" 5877 * building a queue. 5878 */ 5879 bw /= bbr->r_ctl.bbr_hptsi_per_second; 5880 new_tso = roundup(bw, (uint64_t)maxseg); 5881 /* 5882 * Gate the floor to match what our lower than 48Mbps 5883 * algorithm does. The ceiling (bbr_hptsi_segments_max) thus 5884 * becomes the floor for this calculation. 5885 */ 5886 if (new_tso < (bbr->r_ctl.bbr_hptsi_segments_max * maxseg)) 5887 new_tso = (bbr->r_ctl.bbr_hptsi_segments_max * maxseg); 5888 } 5889 if (bbr->r_ctl.bbr_hptsi_segments_floor && (new_tso < (maxseg * bbr->r_ctl.bbr_hptsi_segments_floor))) 5890 new_tso = maxseg * bbr->r_ctl.bbr_hptsi_segments_floor; 5891 if (new_tso > PACE_MAX_IP_BYTES) 5892 new_tso = rounddown(PACE_MAX_IP_BYTES, maxseg); 5893 /* Enforce an utter maximum. */ 5894 if (bbr->r_ctl.bbr_utter_max && (new_tso > (bbr->r_ctl.bbr_utter_max * maxseg))) { 5895 new_tso = bbr->r_ctl.bbr_utter_max * maxseg; 5896 } 5897 if (old_tso != new_tso) { 5898 /* Only log changes */ 5899 bbr_log_type_tsosize(bbr, cts, new_tso, tls_seg, old_tso, maxseg, 0); 5900 bbr->r_ctl.rc_pace_max_segs = new_tso; 5901 } 5902 /* We have hardware pacing! */ 5903 bbr_adjust_for_hw_pacing(bbr, cts); 5904 } 5905 5906 static void 5907 bbr_log_output(struct tcp_bbr *bbr, struct tcpcb *tp, struct tcpopt *to, int32_t len, 5908 uint32_t seq_out, uint8_t th_flags, int32_t err, uint32_t cts, 5909 struct mbuf *mb, int32_t * abandon, struct bbr_sendmap *hintrsm, uint32_t delay_calc, 5910 struct sockbuf *sb) 5911 { 5912 5913 struct bbr_sendmap *rsm, *nrsm; 5914 register uint32_t snd_max, snd_una; 5915 uint32_t pacing_time; 5916 /* 5917 * Add to the RACK log of packets in flight or retransmitted. If 5918 * there is a TS option we will use the TS echoed, if not we will 5919 * grab a TS. 5920 * 5921 * Retransmissions will increment the count and move the ts to its 5922 * proper place. Note that if options do not include TS's then we 5923 * won't be able to effectively use the ACK for an RTT on a retran. 5924 * 5925 * Notes about r_start and r_end. Lets consider a send starting at 5926 * sequence 1 for 10 bytes. In such an example the r_start would be 5927 * 1 (starting sequence) but the r_end would be r_start+len i.e. 11. 5928 * This means that r_end is actually the first sequence for the next 5929 * slot (11). 5930 * 5931 */ 5932 INP_WLOCK_ASSERT(tp->t_inpcb); 5933 if (err) { 5934 /* 5935 * We don't log errors -- we could but snd_max does not 5936 * advance in this case either. 5937 */ 5938 return; 5939 } 5940 if (th_flags & TH_RST) { 5941 /* 5942 * We don't log resets and we return immediately from 5943 * sending 5944 */ 5945 *abandon = 1; 5946 return; 5947 } 5948 snd_una = tp->snd_una; 5949 if (th_flags & (TH_SYN | TH_FIN) && (hintrsm == NULL)) { 5950 /* 5951 * The call to bbr_log_output is made before bumping 5952 * snd_max. This means we can record one extra byte on a SYN 5953 * or FIN if seq_out is adding more on and a FIN is present 5954 * (and we are not resending). 5955 */ 5956 if ((th_flags & TH_SYN) && (tp->iss == seq_out)) 5957 len++; 5958 if (th_flags & TH_FIN) 5959 len++; 5960 } 5961 if (SEQ_LEQ((seq_out + len), snd_una)) { 5962 /* Are sending an old segment to induce an ack (keep-alive)? */ 5963 return; 5964 } 5965 if (SEQ_LT(seq_out, snd_una)) { 5966 /* huh? should we panic? */ 5967 uint32_t end; 5968 5969 end = seq_out + len; 5970 seq_out = snd_una; 5971 len = end - seq_out; 5972 } 5973 snd_max = tp->snd_max; 5974 if (len == 0) { 5975 /* We don't log zero window probes */ 5976 return; 5977 } 5978 pacing_time = bbr_get_pacing_delay(bbr, bbr->r_ctl.rc_bbr_hptsi_gain, len, cts, 1); 5979 /* First question is it a retransmission? */ 5980 if (seq_out == snd_max) { 5981 again: 5982 rsm = bbr_alloc(bbr); 5983 if (rsm == NULL) { 5984 return; 5985 } 5986 rsm->r_flags = 0; 5987 if (th_flags & TH_SYN) 5988 rsm->r_flags |= BBR_HAS_SYN; 5989 if (th_flags & TH_FIN) 5990 rsm->r_flags |= BBR_HAS_FIN; 5991 rsm->r_tim_lastsent[0] = cts; 5992 rsm->r_rtr_cnt = 1; 5993 rsm->r_rtr_bytes = 0; 5994 rsm->r_start = seq_out; 5995 rsm->r_end = rsm->r_start + len; 5996 rsm->r_dupack = 0; 5997 rsm->r_delivered = bbr->r_ctl.rc_delivered; 5998 rsm->r_pacing_delay = pacing_time; 5999 rsm->r_ts_valid = bbr->rc_ts_valid; 6000 if (bbr->rc_ts_valid) 6001 rsm->r_del_ack_ts = bbr->r_ctl.last_inbound_ts; 6002 rsm->r_del_time = bbr->r_ctl.rc_del_time; 6003 if (bbr->r_ctl.r_app_limited_until) 6004 rsm->r_app_limited = 1; 6005 else 6006 rsm->r_app_limited = 0; 6007 rsm->r_first_sent_time = bbr_get_earliest_send_outstanding(bbr, rsm, cts); 6008 rsm->r_flight_at_send = ctf_flight_size(bbr->rc_tp, 6009 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 6010 /* 6011 * Here we must also add in this rsm since snd_max 6012 * is updated after we return from a new send. 6013 */ 6014 rsm->r_flight_at_send += len; 6015 TAILQ_INSERT_TAIL(&bbr->r_ctl.rc_map, rsm, r_next); 6016 TAILQ_INSERT_TAIL(&bbr->r_ctl.rc_tmap, rsm, r_tnext); 6017 rsm->r_in_tmap = 1; 6018 if (bbr->rc_bbr_state == BBR_STATE_PROBE_BW) 6019 rsm->r_bbr_state = bbr_state_val(bbr); 6020 else 6021 rsm->r_bbr_state = 8; 6022 if (bbr->r_ctl.rc_bbr_hptsi_gain > BBR_UNIT) { 6023 rsm->r_is_gain = 1; 6024 rsm->r_is_drain = 0; 6025 } else if (bbr->r_ctl.rc_bbr_hptsi_gain < BBR_UNIT) { 6026 rsm->r_is_drain = 1; 6027 rsm->r_is_gain = 0; 6028 } else { 6029 rsm->r_is_drain = 0; 6030 rsm->r_is_gain = 0; 6031 } 6032 return; 6033 } 6034 /* 6035 * If we reach here its a retransmission and we need to find it. 6036 */ 6037 more: 6038 if (hintrsm && (hintrsm->r_start == seq_out)) { 6039 rsm = hintrsm; 6040 hintrsm = NULL; 6041 } else if (bbr->r_ctl.rc_next) { 6042 /* We have a hint from a previous run */ 6043 rsm = bbr->r_ctl.rc_next; 6044 } else { 6045 /* No hints sorry */ 6046 rsm = NULL; 6047 } 6048 if ((rsm) && (rsm->r_start == seq_out)) { 6049 /* 6050 * We used rc_next or hintrsm to retransmit, hopefully the 6051 * likely case. 6052 */ 6053 seq_out = bbr_update_entry(tp, bbr, rsm, cts, &len, pacing_time); 6054 if (len == 0) { 6055 return; 6056 } else { 6057 goto more; 6058 } 6059 } 6060 /* Ok it was not the last pointer go through it the hard way. */ 6061 TAILQ_FOREACH(rsm, &bbr->r_ctl.rc_map, r_next) { 6062 if (rsm->r_start == seq_out) { 6063 seq_out = bbr_update_entry(tp, bbr, rsm, cts, &len, pacing_time); 6064 bbr->r_ctl.rc_next = TAILQ_NEXT(rsm, r_next); 6065 if (len == 0) { 6066 return; 6067 } else { 6068 continue; 6069 } 6070 } 6071 if (SEQ_GEQ(seq_out, rsm->r_start) && SEQ_LT(seq_out, rsm->r_end)) { 6072 /* Transmitted within this piece */ 6073 /* 6074 * Ok we must split off the front and then let the 6075 * update do the rest 6076 */ 6077 nrsm = bbr_alloc_full_limit(bbr); 6078 if (nrsm == NULL) { 6079 bbr_update_rsm(tp, bbr, rsm, cts, pacing_time); 6080 return; 6081 } 6082 /* 6083 * copy rsm to nrsm and then trim the front of rsm 6084 * to not include this part. 6085 */ 6086 bbr_clone_rsm(bbr, nrsm, rsm, seq_out); 6087 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_map, rsm, nrsm, r_next); 6088 if (rsm->r_in_tmap) { 6089 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, rsm, nrsm, r_tnext); 6090 nrsm->r_in_tmap = 1; 6091 } 6092 rsm->r_flags &= (~BBR_HAS_FIN); 6093 seq_out = bbr_update_entry(tp, bbr, nrsm, cts, &len, pacing_time); 6094 if (len == 0) { 6095 return; 6096 } 6097 } 6098 } 6099 /* 6100 * Hmm not found in map did they retransmit both old and on into the 6101 * new? 6102 */ 6103 if (seq_out == tp->snd_max) { 6104 goto again; 6105 } else if (SEQ_LT(seq_out, tp->snd_max)) { 6106 #ifdef BBR_INVARIANTS 6107 printf("seq_out:%u len:%d snd_una:%u snd_max:%u -- but rsm not found?\n", 6108 seq_out, len, tp->snd_una, tp->snd_max); 6109 printf("Starting Dump of all rack entries\n"); 6110 TAILQ_FOREACH(rsm, &bbr->r_ctl.rc_map, r_next) { 6111 printf("rsm:%p start:%u end:%u\n", 6112 rsm, rsm->r_start, rsm->r_end); 6113 } 6114 printf("Dump complete\n"); 6115 panic("seq_out not found rack:%p tp:%p", 6116 bbr, tp); 6117 #endif 6118 } else { 6119 #ifdef BBR_INVARIANTS 6120 /* 6121 * Hmm beyond sndmax? (only if we are using the new rtt-pack 6122 * flag) 6123 */ 6124 panic("seq_out:%u(%d) is beyond snd_max:%u tp:%p", 6125 seq_out, len, tp->snd_max, tp); 6126 #endif 6127 } 6128 } 6129 6130 static void 6131 bbr_collapse_rtt(struct tcpcb *tp, struct tcp_bbr *bbr, int32_t rtt) 6132 { 6133 /* 6134 * Collapse timeout back the cum-ack moved. 6135 */ 6136 tp->t_rxtshift = 0; 6137 tp->t_softerror = 0; 6138 } 6139 6140 static void 6141 tcp_bbr_xmit_timer(struct tcp_bbr *bbr, uint32_t rtt_usecs, uint32_t rsm_send_time, uint32_t r_start, uint32_t tsin) 6142 { 6143 bbr->rtt_valid = 1; 6144 bbr->r_ctl.cur_rtt = rtt_usecs; 6145 bbr->r_ctl.ts_in = tsin; 6146 if (rsm_send_time) 6147 bbr->r_ctl.cur_rtt_send_time = rsm_send_time; 6148 } 6149 6150 static void 6151 bbr_make_timestamp_determination(struct tcp_bbr *bbr) 6152 { 6153 /** 6154 * We have in our bbr control: 6155 * 1) The timestamp we started observing cum-acks (bbr->r_ctl.bbr_ts_check_tstmp). 6156 * 2) Our timestamp indicating when we sent that packet (bbr->r_ctl.rsm->bbr_ts_check_our_cts). 6157 * 3) The current timestamp that just came in (bbr->r_ctl.last_inbound_ts) 6158 * 4) The time that the packet that generated that ack was sent (bbr->r_ctl.cur_rtt_send_time) 6159 * 6160 * Now we can calculate the time between the sends by doing: 6161 * 6162 * delta = bbr->r_ctl.cur_rtt_send_time - bbr->r_ctl.bbr_ts_check_our_cts 6163 * 6164 * And the peer's time between receiving them by doing: 6165 * 6166 * peer_delta = bbr->r_ctl.last_inbound_ts - bbr->r_ctl.bbr_ts_check_tstmp 6167 * 6168 * We want to figure out if the timestamp values are in msec, 10msec or usec. 6169 * We also may find that we can't use the timestamps if say we see 6170 * that the peer_delta indicates that though we may have taken 10ms to 6171 * pace out the data, it only saw 1ms between the two packets. This would 6172 * indicate that somewhere on the path is a batching entity that is giving 6173 * out time-slices of the actual b/w. This would mean we could not use 6174 * reliably the peers timestamps. 6175 * 6176 * We expect delta > peer_delta initially. Until we figure out the 6177 * timestamp difference which we will store in bbr->r_ctl.bbr_peer_tsratio. 6178 * If we place 1000 there then its a ms vs our usec. If we place 10000 there 6179 * then its 10ms vs our usec. If the peer is running a usec clock we would 6180 * put a 1 there. If the value is faster then ours, we will disable the 6181 * use of timestamps (though we could revist this later if we find it to be not 6182 * just an isolated one or two flows)). 6183 * 6184 * To detect the batching middle boxes we will come up with our compensation and 6185 * if with it in place, we find the peer is drastically off (by some margin) in 6186 * the smaller direction, then we will assume the worst case and disable use of timestamps. 6187 * 6188 */ 6189 uint64_t delta, peer_delta, delta_up; 6190 6191 delta = bbr->r_ctl.cur_rtt_send_time - bbr->r_ctl.bbr_ts_check_our_cts; 6192 if (delta < bbr_min_usec_delta) { 6193 /* 6194 * Have not seen a min amount of time 6195 * between our send times so we can 6196 * make a determination of the timestamp 6197 * yet. 6198 */ 6199 return; 6200 } 6201 peer_delta = bbr->r_ctl.last_inbound_ts - bbr->r_ctl.bbr_ts_check_tstmp; 6202 if (peer_delta < bbr_min_peer_delta) { 6203 /* 6204 * We may have enough in the form of 6205 * our delta but the peers number 6206 * has not changed that much. It could 6207 * be its clock ratio is such that 6208 * we need more data (10ms tick) or 6209 * there may be other compression scenarios 6210 * going on. In any event we need the 6211 * spread to be larger. 6212 */ 6213 return; 6214 } 6215 /* Ok lets first see which way our delta is going */ 6216 if (peer_delta > delta) { 6217 /* Very unlikely, the peer without 6218 * compensation shows that it saw 6219 * the two sends arrive further apart 6220 * then we saw then in micro-seconds. 6221 */ 6222 if (peer_delta < (delta + ((delta * (uint64_t)1000)/ (uint64_t)bbr_delta_percent))) { 6223 /* well it looks like the peer is a micro-second clock. */ 6224 bbr->rc_ts_clock_set = 1; 6225 bbr->r_ctl.bbr_peer_tsratio = 1; 6226 } else { 6227 bbr->rc_ts_cant_be_used = 1; 6228 bbr->rc_ts_clock_set = 1; 6229 } 6230 return; 6231 } 6232 /* Ok we know that the peer_delta is smaller than our send distance */ 6233 bbr->rc_ts_clock_set = 1; 6234 /* First question is it within the percentage that they are using usec time? */ 6235 delta_up = (peer_delta * 1000) / (uint64_t)bbr_delta_percent; 6236 if ((peer_delta + delta_up) >= delta) { 6237 /* Its a usec clock */ 6238 bbr->r_ctl.bbr_peer_tsratio = 1; 6239 bbr_log_tstmp_validation(bbr, peer_delta, delta); 6240 return; 6241 } 6242 /* Ok if not usec, what about 10usec (though unlikely)? */ 6243 delta_up = (peer_delta * 1000 * 10) / (uint64_t)bbr_delta_percent; 6244 if (((peer_delta * 10) + delta_up) >= delta) { 6245 bbr->r_ctl.bbr_peer_tsratio = 10; 6246 bbr_log_tstmp_validation(bbr, peer_delta, delta); 6247 return; 6248 } 6249 /* And what about 100usec (though again unlikely)? */ 6250 delta_up = (peer_delta * 1000 * 100) / (uint64_t)bbr_delta_percent; 6251 if (((peer_delta * 100) + delta_up) >= delta) { 6252 bbr->r_ctl.bbr_peer_tsratio = 100; 6253 bbr_log_tstmp_validation(bbr, peer_delta, delta); 6254 return; 6255 } 6256 /* And how about 1 msec (the most likely one)? */ 6257 delta_up = (peer_delta * 1000 * 1000) / (uint64_t)bbr_delta_percent; 6258 if (((peer_delta * 1000) + delta_up) >= delta) { 6259 bbr->r_ctl.bbr_peer_tsratio = 1000; 6260 bbr_log_tstmp_validation(bbr, peer_delta, delta); 6261 return; 6262 } 6263 /* Ok if not msec could it be 10 msec? */ 6264 delta_up = (peer_delta * 1000 * 10000) / (uint64_t)bbr_delta_percent; 6265 if (((peer_delta * 10000) + delta_up) >= delta) { 6266 bbr->r_ctl.bbr_peer_tsratio = 10000; 6267 return; 6268 } 6269 /* If we fall down here the clock tick so slowly we can't use it */ 6270 bbr->rc_ts_cant_be_used = 1; 6271 bbr->r_ctl.bbr_peer_tsratio = 0; 6272 bbr_log_tstmp_validation(bbr, peer_delta, delta); 6273 } 6274 6275 /* 6276 * Collect new round-trip time estimate 6277 * and update averages and current timeout. 6278 */ 6279 static void 6280 tcp_bbr_xmit_timer_commit(struct tcp_bbr *bbr, struct tcpcb *tp, uint32_t cts) 6281 { 6282 int32_t delta; 6283 uint32_t rtt, tsin; 6284 int32_t rtt_ticks; 6285 6286 if (bbr->rtt_valid == 0) 6287 /* No valid sample */ 6288 return; 6289 6290 rtt = bbr->r_ctl.cur_rtt; 6291 tsin = bbr->r_ctl.ts_in; 6292 if (bbr->rc_prtt_set_ts) { 6293 /* 6294 * We are to force feed the rttProp filter due 6295 * to an entry into PROBE_RTT. This assures 6296 * that the times are sync'd between when we 6297 * go into PROBE_RTT and the filter expiration. 6298 * 6299 * Google does not use a true filter, so they do 6300 * this implicitly since they only keep one value 6301 * and when they enter probe-rtt they update the 6302 * value to the newest rtt. 6303 */ 6304 uint32_t rtt_prop; 6305 6306 bbr->rc_prtt_set_ts = 0; 6307 rtt_prop = get_filter_value_small(&bbr->r_ctl.rc_rttprop); 6308 if (rtt > rtt_prop) 6309 filter_increase_by_small(&bbr->r_ctl.rc_rttprop, (rtt - rtt_prop), cts); 6310 else 6311 apply_filter_min_small(&bbr->r_ctl.rc_rttprop, rtt, cts); 6312 } 6313 if (bbr->rc_ack_was_delayed) 6314 rtt += bbr->r_ctl.rc_ack_hdwr_delay; 6315 6316 if (rtt < bbr->r_ctl.rc_lowest_rtt) 6317 bbr->r_ctl.rc_lowest_rtt = rtt; 6318 bbr_log_rtt_sample(bbr, rtt, tsin); 6319 if (bbr->r_init_rtt) { 6320 /* 6321 * The initial rtt is not-trusted, nuke it and lets get 6322 * our first valid measurement in. 6323 */ 6324 bbr->r_init_rtt = 0; 6325 tp->t_srtt = 0; 6326 } 6327 if ((bbr->rc_ts_clock_set == 0) && bbr->rc_ts_valid) { 6328 /* 6329 * So we have not yet figured out 6330 * what the peers TSTMP value is 6331 * in (most likely ms). We need a 6332 * series of cum-ack's to determine 6333 * this reliably. 6334 */ 6335 if (bbr->rc_ack_is_cumack) { 6336 if (bbr->rc_ts_data_set) { 6337 /* Lets attempt to determine the timestamp granularity. */ 6338 bbr_make_timestamp_determination(bbr); 6339 } else { 6340 bbr->rc_ts_data_set = 1; 6341 bbr->r_ctl.bbr_ts_check_tstmp = bbr->r_ctl.last_inbound_ts; 6342 bbr->r_ctl.bbr_ts_check_our_cts = bbr->r_ctl.cur_rtt_send_time; 6343 } 6344 } else { 6345 /* 6346 * We have to have consecutive acks 6347 * reset any "filled" state to none. 6348 */ 6349 bbr->rc_ts_data_set = 0; 6350 } 6351 } 6352 /* Round it up */ 6353 rtt_ticks = USEC_2_TICKS((rtt + (USECS_IN_MSEC - 1))); 6354 if (rtt_ticks == 0) 6355 rtt_ticks = 1; 6356 if (tp->t_srtt != 0) { 6357 /* 6358 * srtt is stored as fixed point with 5 bits after the 6359 * binary point (i.e., scaled by 8). The following magic is 6360 * equivalent to the smoothing algorithm in rfc793 with an 6361 * alpha of .875 (srtt = rtt/8 + srtt*7/8 in fixed point). 6362 * Adjust rtt to origin 0. 6363 */ 6364 6365 delta = ((rtt_ticks - 1) << TCP_DELTA_SHIFT) 6366 - (tp->t_srtt >> (TCP_RTT_SHIFT - TCP_DELTA_SHIFT)); 6367 6368 tp->t_srtt += delta; 6369 if (tp->t_srtt <= 0) 6370 tp->t_srtt = 1; 6371 6372 /* 6373 * We accumulate a smoothed rtt variance (actually, a 6374 * smoothed mean difference), then set the retransmit timer 6375 * to smoothed rtt + 4 times the smoothed variance. rttvar 6376 * is stored as fixed point with 4 bits after the binary 6377 * point (scaled by 16). The following is equivalent to 6378 * rfc793 smoothing with an alpha of .75 (rttvar = 6379 * rttvar*3/4 + |delta| / 4). This replaces rfc793's 6380 * wired-in beta. 6381 */ 6382 if (delta < 0) 6383 delta = -delta; 6384 delta -= tp->t_rttvar >> (TCP_RTTVAR_SHIFT - TCP_DELTA_SHIFT); 6385 tp->t_rttvar += delta; 6386 if (tp->t_rttvar <= 0) 6387 tp->t_rttvar = 1; 6388 if (tp->t_rttbest > tp->t_srtt + tp->t_rttvar) 6389 tp->t_rttbest = tp->t_srtt + tp->t_rttvar; 6390 } else { 6391 /* 6392 * No rtt measurement yet - use the unsmoothed rtt. Set the 6393 * variance to half the rtt (so our first retransmit happens 6394 * at 3*rtt). 6395 */ 6396 tp->t_srtt = rtt_ticks << TCP_RTT_SHIFT; 6397 tp->t_rttvar = rtt_ticks << (TCP_RTTVAR_SHIFT - 1); 6398 tp->t_rttbest = tp->t_srtt + tp->t_rttvar; 6399 } 6400 KMOD_TCPSTAT_INC(tcps_rttupdated); 6401 tp->t_rttupdated++; 6402 #ifdef STATS 6403 stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_RTT, imax(0, rtt_ticks)); 6404 #endif 6405 /* 6406 * the retransmit should happen at rtt + 4 * rttvar. Because of the 6407 * way we do the smoothing, srtt and rttvar will each average +1/2 6408 * tick of bias. When we compute the retransmit timer, we want 1/2 6409 * tick of rounding and 1 extra tick because of +-1/2 tick 6410 * uncertainty in the firing of the timer. The bias will give us 6411 * exactly the 1.5 tick we need. But, because the bias is 6412 * statistical, we have to test that we don't drop below the minimum 6413 * feasible timer (which is 2 ticks). 6414 */ 6415 TCPT_RANGESET(tp->t_rxtcur, TCP_REXMTVAL(tp), 6416 max(MSEC_2_TICKS(bbr->r_ctl.rc_min_rto_ms), rtt_ticks + 2), 6417 MSEC_2_TICKS(((uint32_t)bbr->rc_max_rto_sec) * 1000)); 6418 6419 /* 6420 * We received an ack for a packet that wasn't retransmitted; it is 6421 * probably safe to discard any error indications we've received 6422 * recently. This isn't quite right, but close enough for now (a 6423 * route might have failed after we sent a segment, and the return 6424 * path might not be symmetrical). 6425 */ 6426 tp->t_softerror = 0; 6427 rtt = (TICKS_2_USEC(bbr->rc_tp->t_srtt) >> TCP_RTT_SHIFT); 6428 if (bbr->r_ctl.bbr_smallest_srtt_this_state > rtt) 6429 bbr->r_ctl.bbr_smallest_srtt_this_state = rtt; 6430 } 6431 6432 static void 6433 bbr_earlier_retran(struct tcpcb *tp, struct tcp_bbr *bbr, struct bbr_sendmap *rsm, 6434 uint32_t t, uint32_t cts, int ack_type) 6435 { 6436 /* 6437 * For this RSM, we acknowledged the data from a previous 6438 * transmission, not the last one we made. This means we did a false 6439 * retransmit. 6440 */ 6441 if (rsm->r_flags & BBR_HAS_FIN) { 6442 /* 6443 * The sending of the FIN often is multiple sent when we 6444 * have everything outstanding ack'd. We ignore this case 6445 * since its over now. 6446 */ 6447 return; 6448 } 6449 if (rsm->r_flags & BBR_TLP) { 6450 /* 6451 * We expect TLP's to have this occur often 6452 */ 6453 bbr->rc_tlp_rtx_out = 0; 6454 return; 6455 } 6456 if (ack_type != BBR_CUM_ACKED) { 6457 /* 6458 * If it was not a cum-ack we 6459 * don't really know for sure since 6460 * the timestamp could be from some 6461 * other transmission. 6462 */ 6463 return; 6464 } 6465 6466 if (rsm->r_flags & BBR_WAS_SACKPASS) { 6467 /* 6468 * We retransmitted based on a sack and the earlier 6469 * retransmission ack'd it - re-ordering is occuring. 6470 */ 6471 BBR_STAT_INC(bbr_reorder_seen); 6472 bbr->r_ctl.rc_reorder_ts = cts; 6473 } 6474 /* Back down the loss count */ 6475 if (rsm->r_flags & BBR_MARKED_LOST) { 6476 bbr->r_ctl.rc_lost -= rsm->r_end - rsm->r_start; 6477 bbr->r_ctl.rc_lost_bytes -= rsm->r_end - rsm->r_start; 6478 rsm->r_flags &= ~BBR_MARKED_LOST; 6479 if (SEQ_GT(bbr->r_ctl.rc_lt_lost, bbr->r_ctl.rc_lost)) 6480 /* LT sampling also needs adjustment */ 6481 bbr->r_ctl.rc_lt_lost = bbr->r_ctl.rc_lost; 6482 } 6483 /***** RRS HERE ************************/ 6484 /* Do we need to do this??? */ 6485 /* bbr_reset_lt_bw_sampling(bbr, cts); */ 6486 /***** RRS HERE ************************/ 6487 BBR_STAT_INC(bbr_badfr); 6488 BBR_STAT_ADD(bbr_badfr_bytes, (rsm->r_end - rsm->r_start)); 6489 } 6490 6491 static void 6492 bbr_set_reduced_rtt(struct tcp_bbr *bbr, uint32_t cts, uint32_t line) 6493 { 6494 bbr->r_ctl.rc_rtt_shrinks = cts; 6495 if (bbr_can_force_probertt && 6496 (TSTMP_GT(cts, bbr->r_ctl.last_in_probertt)) && 6497 ((cts - bbr->r_ctl.last_in_probertt) > bbr->r_ctl.rc_probertt_int)) { 6498 /* 6499 * We should enter probe-rtt its been too long 6500 * since we have been there. 6501 */ 6502 bbr_enter_probe_rtt(bbr, cts, __LINE__); 6503 } else 6504 bbr_check_probe_rtt_limits(bbr, cts); 6505 } 6506 6507 static void 6508 tcp_bbr_commit_bw(struct tcp_bbr *bbr, uint32_t cts) 6509 { 6510 uint64_t orig_bw; 6511 6512 if (bbr->r_ctl.rc_bbr_cur_del_rate == 0) { 6513 /* We never apply a zero measurment */ 6514 bbr_log_type_bbrupd(bbr, 20, cts, 0, 0, 6515 0, 0, 0, 0, 0, 0); 6516 return; 6517 } 6518 if (bbr->r_ctl.r_measurement_count < 0xffffffff) 6519 bbr->r_ctl.r_measurement_count++; 6520 orig_bw = get_filter_value(&bbr->r_ctl.rc_delrate); 6521 apply_filter_max(&bbr->r_ctl.rc_delrate, bbr->r_ctl.rc_bbr_cur_del_rate, bbr->r_ctl.rc_pkt_epoch); 6522 bbr_log_type_bbrupd(bbr, 21, cts, (uint32_t)orig_bw, 6523 (uint32_t)get_filter_value(&bbr->r_ctl.rc_delrate), 6524 0, 0, 0, 0, 0, 0); 6525 if (orig_bw && 6526 (orig_bw != get_filter_value(&bbr->r_ctl.rc_delrate))) { 6527 if (bbr->bbr_hdrw_pacing) { 6528 /* 6529 * Apply a new rate to the hardware 6530 * possibly. 6531 */ 6532 bbr_update_hardware_pacing_rate(bbr, cts); 6533 } 6534 bbr_set_state_target(bbr, __LINE__); 6535 tcp_bbr_tso_size_check(bbr, cts); 6536 if (bbr->r_recovery_bw) { 6537 bbr_setup_red_bw(bbr, cts); 6538 bbr_log_type_bw_reduce(bbr, BBR_RED_BW_USELRBW); 6539 } 6540 } else if ((orig_bw == 0) && get_filter_value(&bbr->r_ctl.rc_delrate)) 6541 tcp_bbr_tso_size_check(bbr, cts); 6542 } 6543 6544 static void 6545 bbr_nf_measurement(struct tcp_bbr *bbr, struct bbr_sendmap *rsm, uint32_t rtt, uint32_t cts) 6546 { 6547 if (bbr->rc_in_persist == 0) { 6548 /* We log only when not in persist */ 6549 /* Translate to a Bytes Per Second */ 6550 uint64_t tim, bw, ts_diff, ts_bw; 6551 uint32_t upper, lower, delivered; 6552 6553 if (TSTMP_GT(bbr->r_ctl.rc_del_time, rsm->r_del_time)) 6554 tim = (uint64_t)(bbr->r_ctl.rc_del_time - rsm->r_del_time); 6555 else 6556 tim = 1; 6557 /* 6558 * Now that we have processed the tim (skipping the sample 6559 * or possibly updating the time, go ahead and 6560 * calculate the cdr. 6561 */ 6562 delivered = (bbr->r_ctl.rc_delivered - rsm->r_delivered); 6563 bw = (uint64_t)delivered; 6564 bw *= (uint64_t)USECS_IN_SECOND; 6565 bw /= tim; 6566 if (bw == 0) { 6567 /* We must have a calculatable amount */ 6568 return; 6569 } 6570 upper = (bw >> 32) & 0x00000000ffffffff; 6571 lower = bw & 0x00000000ffffffff; 6572 /* 6573 * If we are using this b/w shove it in now so we 6574 * can see in the trace viewer if it gets over-ridden. 6575 */ 6576 if (rsm->r_ts_valid && 6577 bbr->rc_ts_valid && 6578 bbr->rc_ts_clock_set && 6579 (bbr->rc_ts_cant_be_used == 0) && 6580 bbr->rc_use_ts_limit) { 6581 ts_diff = max((bbr->r_ctl.last_inbound_ts - rsm->r_del_ack_ts), 1); 6582 ts_diff *= bbr->r_ctl.bbr_peer_tsratio; 6583 if ((delivered == 0) || 6584 (rtt < 1000)) { 6585 /* Can't use the ts */ 6586 bbr_log_type_bbrupd(bbr, 61, cts, 6587 ts_diff, 6588 bbr->r_ctl.last_inbound_ts, 6589 rsm->r_del_ack_ts, 0, 6590 0, 0, 0, delivered); 6591 } else { 6592 ts_bw = (uint64_t)delivered; 6593 ts_bw *= (uint64_t)USECS_IN_SECOND; 6594 ts_bw /= ts_diff; 6595 bbr_log_type_bbrupd(bbr, 62, cts, 6596 (ts_bw >> 32), 6597 (ts_bw & 0xffffffff), 0, 0, 6598 0, 0, ts_diff, delivered); 6599 if ((bbr->ts_can_raise) && 6600 (ts_bw > bw)) { 6601 bbr_log_type_bbrupd(bbr, 8, cts, 6602 delivered, 6603 ts_diff, 6604 (bw >> 32), 6605 (bw & 0x00000000ffffffff), 6606 0, 0, 0, 0); 6607 bw = ts_bw; 6608 } else if (ts_bw && (ts_bw < bw)) { 6609 bbr_log_type_bbrupd(bbr, 7, cts, 6610 delivered, 6611 ts_diff, 6612 (bw >> 32), 6613 (bw & 0x00000000ffffffff), 6614 0, 0, 0, 0); 6615 bw = ts_bw; 6616 } 6617 } 6618 } 6619 if (rsm->r_first_sent_time && 6620 TSTMP_GT(rsm->r_tim_lastsent[(rsm->r_rtr_cnt -1)],rsm->r_first_sent_time)) { 6621 uint64_t sbw, sti; 6622 /* 6623 * We use what was in flight at the time of our 6624 * send and the size of this send to figure 6625 * out what we have been sending at (amount). 6626 * For the time we take from the time of 6627 * the send of the first send outstanding 6628 * until this send plus this sends pacing 6629 * time. This gives us a good calculation 6630 * as to the rate we have been sending at. 6631 */ 6632 6633 sbw = (uint64_t)(rsm->r_flight_at_send); 6634 sbw *= (uint64_t)USECS_IN_SECOND; 6635 sti = rsm->r_tim_lastsent[(rsm->r_rtr_cnt -1)] - rsm->r_first_sent_time; 6636 sti += rsm->r_pacing_delay; 6637 sbw /= sti; 6638 if (sbw < bw) { 6639 bbr_log_type_bbrupd(bbr, 6, cts, 6640 delivered, 6641 (uint32_t)sti, 6642 (bw >> 32), 6643 (uint32_t)bw, 6644 rsm->r_first_sent_time, 0, (sbw >> 32), 6645 (uint32_t)sbw); 6646 bw = sbw; 6647 } 6648 } 6649 /* Use the google algorithm for b/w measurements */ 6650 bbr->r_ctl.rc_bbr_cur_del_rate = bw; 6651 if ((rsm->r_app_limited == 0) || 6652 (bw > get_filter_value(&bbr->r_ctl.rc_delrate))) { 6653 tcp_bbr_commit_bw(bbr, cts); 6654 bbr_log_type_bbrupd(bbr, 10, cts, (uint32_t)tim, delivered, 6655 0, 0, 0, 0, bbr->r_ctl.rc_del_time, rsm->r_del_time); 6656 } 6657 } 6658 } 6659 6660 static void 6661 bbr_google_measurement(struct tcp_bbr *bbr, struct bbr_sendmap *rsm, uint32_t rtt, uint32_t cts) 6662 { 6663 if (bbr->rc_in_persist == 0) { 6664 /* We log only when not in persist */ 6665 /* Translate to a Bytes Per Second */ 6666 uint64_t tim, bw; 6667 uint32_t upper, lower, delivered; 6668 int no_apply = 0; 6669 6670 if (TSTMP_GT(bbr->r_ctl.rc_del_time, rsm->r_del_time)) 6671 tim = (uint64_t)(bbr->r_ctl.rc_del_time - rsm->r_del_time); 6672 else 6673 tim = 1; 6674 /* 6675 * Now that we have processed the tim (skipping the sample 6676 * or possibly updating the time, go ahead and 6677 * calculate the cdr. 6678 */ 6679 delivered = (bbr->r_ctl.rc_delivered - rsm->r_delivered); 6680 bw = (uint64_t)delivered; 6681 bw *= (uint64_t)USECS_IN_SECOND; 6682 bw /= tim; 6683 if (tim < bbr->r_ctl.rc_lowest_rtt) { 6684 bbr_log_type_bbrupd(bbr, 99, cts, (uint32_t)tim, delivered, 6685 tim, bbr->r_ctl.rc_lowest_rtt, 0, 0, 0, 0); 6686 6687 no_apply = 1; 6688 } 6689 upper = (bw >> 32) & 0x00000000ffffffff; 6690 lower = bw & 0x00000000ffffffff; 6691 /* 6692 * If we are using this b/w shove it in now so we 6693 * can see in the trace viewer if it gets over-ridden. 6694 */ 6695 bbr->r_ctl.rc_bbr_cur_del_rate = bw; 6696 /* Gate by the sending rate */ 6697 if (rsm->r_first_sent_time && 6698 TSTMP_GT(rsm->r_tim_lastsent[(rsm->r_rtr_cnt -1)],rsm->r_first_sent_time)) { 6699 uint64_t sbw, sti; 6700 /* 6701 * We use what was in flight at the time of our 6702 * send and the size of this send to figure 6703 * out what we have been sending at (amount). 6704 * For the time we take from the time of 6705 * the send of the first send outstanding 6706 * until this send plus this sends pacing 6707 * time. This gives us a good calculation 6708 * as to the rate we have been sending at. 6709 */ 6710 6711 sbw = (uint64_t)(rsm->r_flight_at_send); 6712 sbw *= (uint64_t)USECS_IN_SECOND; 6713 sti = rsm->r_tim_lastsent[(rsm->r_rtr_cnt -1)] - rsm->r_first_sent_time; 6714 sti += rsm->r_pacing_delay; 6715 sbw /= sti; 6716 if (sbw < bw) { 6717 bbr_log_type_bbrupd(bbr, 6, cts, 6718 delivered, 6719 (uint32_t)sti, 6720 (bw >> 32), 6721 (uint32_t)bw, 6722 rsm->r_first_sent_time, 0, (sbw >> 32), 6723 (uint32_t)sbw); 6724 bw = sbw; 6725 } 6726 if ((sti > tim) && 6727 (sti < bbr->r_ctl.rc_lowest_rtt)) { 6728 bbr_log_type_bbrupd(bbr, 99, cts, (uint32_t)tim, delivered, 6729 (uint32_t)sti, bbr->r_ctl.rc_lowest_rtt, 0, 0, 0, 0); 6730 no_apply = 1; 6731 } else 6732 no_apply = 0; 6733 } 6734 bbr->r_ctl.rc_bbr_cur_del_rate = bw; 6735 if ((no_apply == 0) && 6736 ((rsm->r_app_limited == 0) || 6737 (bw > get_filter_value(&bbr->r_ctl.rc_delrate)))) { 6738 tcp_bbr_commit_bw(bbr, cts); 6739 bbr_log_type_bbrupd(bbr, 10, cts, (uint32_t)tim, delivered, 6740 0, 0, 0, 0, bbr->r_ctl.rc_del_time, rsm->r_del_time); 6741 } 6742 } 6743 } 6744 6745 static void 6746 bbr_update_bbr_info(struct tcp_bbr *bbr, struct bbr_sendmap *rsm, uint32_t rtt, uint32_t cts, uint32_t tsin, 6747 uint32_t uts, int32_t match, uint32_t rsm_send_time, int32_t ack_type, struct tcpopt *to) 6748 { 6749 uint64_t old_rttprop; 6750 6751 /* Update our delivery time and amount */ 6752 bbr->r_ctl.rc_delivered += (rsm->r_end - rsm->r_start); 6753 bbr->r_ctl.rc_del_time = cts; 6754 if (rtt == 0) { 6755 /* 6756 * 0 means its a retransmit, for now we don't use these for 6757 * the rest of BBR. 6758 */ 6759 return; 6760 } 6761 if ((bbr->rc_use_google == 0) && 6762 (match != BBR_RTT_BY_EXACTMATCH) && 6763 (match != BBR_RTT_BY_TIMESTAMP)){ 6764 /* 6765 * We get a lot of rtt updates, lets not pay attention to 6766 * any that are not an exact match. That way we don't have 6767 * to worry about timestamps and the whole nonsense of 6768 * unsure if its a retransmission etc (if we ever had the 6769 * timestamp fixed to always have the last thing sent this 6770 * would not be a issue). 6771 */ 6772 return; 6773 } 6774 if ((bbr_no_retran && bbr->rc_use_google) && 6775 (match != BBR_RTT_BY_EXACTMATCH) && 6776 (match != BBR_RTT_BY_TIMESTAMP)){ 6777 /* 6778 * We only do measurements in google mode 6779 * with bbr_no_retran on for sure things. 6780 */ 6781 return; 6782 } 6783 /* Only update srtt if we know by exact match */ 6784 tcp_bbr_xmit_timer(bbr, rtt, rsm_send_time, rsm->r_start, tsin); 6785 if (ack_type == BBR_CUM_ACKED) 6786 bbr->rc_ack_is_cumack = 1; 6787 else 6788 bbr->rc_ack_is_cumack = 0; 6789 old_rttprop = bbr_get_rtt(bbr, BBR_RTT_PROP); 6790 /* 6791 * Note the following code differs to the original 6792 * BBR spec. It calls for <= not <. However after a 6793 * long discussion in email with Neal, he acknowledged 6794 * that it should be < than so that we will have flows 6795 * going into probe-rtt (we were seeing cases where that 6796 * did not happen and caused ugly things to occur). We 6797 * have added this agreed upon fix to our code base. 6798 */ 6799 if (rtt < old_rttprop) { 6800 /* Update when we last saw a rtt drop */ 6801 bbr_log_rtt_shrinks(bbr, cts, 0, rtt, __LINE__, BBR_RTTS_NEWRTT, 0); 6802 bbr_set_reduced_rtt(bbr, cts, __LINE__); 6803 } 6804 bbr_log_type_bbrrttprop(bbr, rtt, (rsm ? rsm->r_end : 0), uts, cts, 6805 match, rsm->r_start, rsm->r_flags); 6806 apply_filter_min_small(&bbr->r_ctl.rc_rttprop, rtt, cts); 6807 if (old_rttprop != bbr_get_rtt(bbr, BBR_RTT_PROP)) { 6808 /* 6809 * The RTT-prop moved, reset the target (may be a 6810 * nop for some states). 6811 */ 6812 bbr_set_state_target(bbr, __LINE__); 6813 if (bbr->rc_bbr_state == BBR_STATE_PROBE_RTT) 6814 bbr_log_rtt_shrinks(bbr, cts, 0, 0, 6815 __LINE__, BBR_RTTS_NEW_TARGET, 0); 6816 else if (old_rttprop < bbr_get_rtt(bbr, BBR_RTT_PROP)) 6817 /* It went up */ 6818 bbr_check_probe_rtt_limits(bbr, cts); 6819 } 6820 if ((bbr->rc_use_google == 0) && 6821 (match == BBR_RTT_BY_TIMESTAMP)) { 6822 /* 6823 * We don't do b/w update with 6824 * these since they are not really 6825 * reliable. 6826 */ 6827 return; 6828 } 6829 if (bbr->r_ctl.r_app_limited_until && 6830 (bbr->r_ctl.rc_delivered >= bbr->r_ctl.r_app_limited_until)) { 6831 /* We are no longer app-limited */ 6832 bbr->r_ctl.r_app_limited_until = 0; 6833 } 6834 if (bbr->rc_use_google) { 6835 bbr_google_measurement(bbr, rsm, rtt, cts); 6836 } else { 6837 bbr_nf_measurement(bbr, rsm, rtt, cts); 6838 } 6839 } 6840 6841 /* 6842 * Convert a timestamp that the main stack 6843 * uses (milliseconds) into one that bbr uses 6844 * (microseconds). Return that converted timestamp. 6845 */ 6846 static uint32_t 6847 bbr_ts_convert(uint32_t cts) { 6848 uint32_t sec, msec; 6849 6850 sec = cts / MS_IN_USEC; 6851 msec = cts - (MS_IN_USEC * sec); 6852 return ((sec * USECS_IN_SECOND) + (msec * MS_IN_USEC)); 6853 } 6854 6855 /* 6856 * Return 0 if we did not update the RTT time, return 6857 * 1 if we did. 6858 */ 6859 static int 6860 bbr_update_rtt(struct tcpcb *tp, struct tcp_bbr *bbr, 6861 struct bbr_sendmap *rsm, struct tcpopt *to, uint32_t cts, int32_t ack_type, uint32_t th_ack) 6862 { 6863 int32_t i; 6864 uint32_t t, uts = 0; 6865 6866 if ((rsm->r_flags & BBR_ACKED) || 6867 (rsm->r_flags & BBR_WAS_RENEGED) || 6868 (rsm->r_flags & BBR_RXT_CLEARED)) { 6869 /* Already done */ 6870 return (0); 6871 } 6872 if (rsm->r_rtr_cnt == 1) { 6873 /* 6874 * Only one transmit. Hopefully the normal case. 6875 */ 6876 if (TSTMP_GT(cts, rsm->r_tim_lastsent[0])) 6877 t = cts - rsm->r_tim_lastsent[0]; 6878 else 6879 t = 1; 6880 if ((int)t <= 0) 6881 t = 1; 6882 bbr->r_ctl.rc_last_rtt = t; 6883 bbr_update_bbr_info(bbr, rsm, t, cts, to->to_tsecr, 0, 6884 BBR_RTT_BY_EXACTMATCH, rsm->r_tim_lastsent[0], ack_type, to); 6885 return (1); 6886 } 6887 /* Convert to usecs */ 6888 if ((bbr_can_use_ts_for_rtt == 1) && 6889 (bbr->rc_use_google == 1) && 6890 (ack_type == BBR_CUM_ACKED) && 6891 (to->to_flags & TOF_TS) && 6892 (to->to_tsecr != 0)) { 6893 t = tcp_tv_to_mssectick(&bbr->rc_tv) - to->to_tsecr; 6894 if (t < 1) 6895 t = 1; 6896 t *= MS_IN_USEC; 6897 bbr_update_bbr_info(bbr, rsm, t, cts, to->to_tsecr, 0, 6898 BBR_RTT_BY_TIMESTAMP, 6899 rsm->r_tim_lastsent[(rsm->r_rtr_cnt-1)], 6900 ack_type, to); 6901 return (1); 6902 } 6903 uts = bbr_ts_convert(to->to_tsecr); 6904 if ((to->to_flags & TOF_TS) && 6905 (to->to_tsecr != 0) && 6906 (ack_type == BBR_CUM_ACKED) && 6907 ((rsm->r_flags & BBR_OVERMAX) == 0)) { 6908 /* 6909 * Now which timestamp does it match? In this block the ACK 6910 * may be coming from a previous transmission. 6911 */ 6912 uint32_t fudge; 6913 6914 fudge = BBR_TIMER_FUDGE; 6915 for (i = 0; i < rsm->r_rtr_cnt; i++) { 6916 if ((SEQ_GEQ(uts, (rsm->r_tim_lastsent[i] - fudge))) && 6917 (SEQ_LEQ(uts, (rsm->r_tim_lastsent[i] + fudge)))) { 6918 if (TSTMP_GT(cts, rsm->r_tim_lastsent[i])) 6919 t = cts - rsm->r_tim_lastsent[i]; 6920 else 6921 t = 1; 6922 if ((int)t <= 0) 6923 t = 1; 6924 bbr->r_ctl.rc_last_rtt = t; 6925 bbr_update_bbr_info(bbr, rsm, t, cts, to->to_tsecr, uts, BBR_RTT_BY_TSMATCHING, 6926 rsm->r_tim_lastsent[i], ack_type, to); 6927 if ((i + 1) < rsm->r_rtr_cnt) { 6928 /* Likely */ 6929 bbr_earlier_retran(tp, bbr, rsm, t, cts, ack_type); 6930 } else if (rsm->r_flags & BBR_TLP) { 6931 bbr->rc_tlp_rtx_out = 0; 6932 } 6933 return (1); 6934 } 6935 } 6936 /* Fall through if we can't find a matching timestamp */ 6937 } 6938 /* 6939 * Ok its a SACK block that we retransmitted. or a windows 6940 * machine without timestamps. We can tell nothing from the 6941 * time-stamp since its not there or the time the peer last 6942 * recieved a segment that moved forward its cum-ack point. 6943 * 6944 * Lets look at the last retransmit and see what we can tell 6945 * (with BBR for space we only keep 2 note we have to keep 6946 * at least 2 so the map can not be condensed more). 6947 */ 6948 i = rsm->r_rtr_cnt - 1; 6949 if (TSTMP_GT(cts, rsm->r_tim_lastsent[i])) 6950 t = cts - rsm->r_tim_lastsent[i]; 6951 else 6952 goto not_sure; 6953 if (t < bbr->r_ctl.rc_lowest_rtt) { 6954 /* 6955 * We retransmitted and the ack came back in less 6956 * than the smallest rtt we have observed in the 6957 * windowed rtt. We most likey did an improper 6958 * retransmit as outlined in 4.2 Step 3 point 2 in 6959 * the rack-draft. 6960 * 6961 * Use the prior transmission to update all the 6962 * information as long as there is only one prior 6963 * transmission. 6964 */ 6965 if ((rsm->r_flags & BBR_OVERMAX) == 0) { 6966 #ifdef BBR_INVARIANTS 6967 if (rsm->r_rtr_cnt == 1) 6968 panic("rsm:%p bbr:%p rsm has overmax and only 1 retranmit flags:%x?", rsm, bbr, rsm->r_flags); 6969 #endif 6970 i = rsm->r_rtr_cnt - 2; 6971 if (TSTMP_GT(cts, rsm->r_tim_lastsent[i])) 6972 t = cts - rsm->r_tim_lastsent[i]; 6973 else 6974 t = 1; 6975 bbr_update_bbr_info(bbr, rsm, t, cts, to->to_tsecr, uts, BBR_RTT_BY_EARLIER_RET, 6976 rsm->r_tim_lastsent[i], ack_type, to); 6977 bbr_earlier_retran(tp, bbr, rsm, t, cts, ack_type); 6978 } else { 6979 /* 6980 * Too many prior transmissions, just 6981 * updated BBR delivered 6982 */ 6983 not_sure: 6984 bbr_update_bbr_info(bbr, rsm, 0, cts, to->to_tsecr, uts, 6985 BBR_RTT_BY_SOME_RETRAN, 0, ack_type, to); 6986 } 6987 } else { 6988 /* 6989 * We retransmitted it and the retransmit did the 6990 * job. 6991 */ 6992 if (rsm->r_flags & BBR_TLP) 6993 bbr->rc_tlp_rtx_out = 0; 6994 if ((rsm->r_flags & BBR_OVERMAX) == 0) 6995 bbr_update_bbr_info(bbr, rsm, t, cts, to->to_tsecr, uts, 6996 BBR_RTT_BY_THIS_RETRAN, 0, ack_type, to); 6997 else 6998 bbr_update_bbr_info(bbr, rsm, 0, cts, to->to_tsecr, uts, 6999 BBR_RTT_BY_SOME_RETRAN, 0, ack_type, to); 7000 return (1); 7001 } 7002 return (0); 7003 } 7004 7005 /* 7006 * Mark the SACK_PASSED flag on all entries prior to rsm send wise. 7007 */ 7008 static void 7009 bbr_log_sack_passed(struct tcpcb *tp, 7010 struct tcp_bbr *bbr, struct bbr_sendmap *rsm) 7011 { 7012 struct bbr_sendmap *nrsm; 7013 7014 nrsm = rsm; 7015 TAILQ_FOREACH_REVERSE_FROM(nrsm, &bbr->r_ctl.rc_tmap, 7016 bbr_head, r_tnext) { 7017 if (nrsm == rsm) { 7018 /* Skip orginal segment he is acked */ 7019 continue; 7020 } 7021 if (nrsm->r_flags & BBR_ACKED) { 7022 /* Skip ack'd segments */ 7023 continue; 7024 } 7025 if (nrsm->r_flags & BBR_SACK_PASSED) { 7026 /* 7027 * We found one that is already marked 7028 * passed, we have been here before and 7029 * so all others below this are marked. 7030 */ 7031 break; 7032 } 7033 BBR_STAT_INC(bbr_sack_passed); 7034 nrsm->r_flags |= BBR_SACK_PASSED; 7035 if (((nrsm->r_flags & BBR_MARKED_LOST) == 0) && 7036 bbr_is_lost(bbr, nrsm, bbr->r_ctl.rc_rcvtime)) { 7037 bbr->r_ctl.rc_lost += nrsm->r_end - nrsm->r_start; 7038 bbr->r_ctl.rc_lost_bytes += nrsm->r_end - nrsm->r_start; 7039 nrsm->r_flags |= BBR_MARKED_LOST; 7040 } 7041 nrsm->r_flags &= ~BBR_WAS_SACKPASS; 7042 } 7043 } 7044 7045 /* 7046 * Returns the number of bytes that were 7047 * newly ack'd by sack blocks. 7048 */ 7049 static uint32_t 7050 bbr_proc_sack_blk(struct tcpcb *tp, struct tcp_bbr *bbr, struct sackblk *sack, 7051 struct tcpopt *to, struct bbr_sendmap **prsm, uint32_t cts) 7052 { 7053 int32_t times = 0; 7054 uint32_t start, end, maxseg, changed = 0; 7055 struct bbr_sendmap *rsm, *nrsm; 7056 int32_t used_ref = 1; 7057 uint8_t went_back = 0, went_fwd = 0; 7058 7059 maxseg = tp->t_maxseg - bbr->rc_last_options; 7060 start = sack->start; 7061 end = sack->end; 7062 rsm = *prsm; 7063 if (rsm == NULL) 7064 used_ref = 0; 7065 7066 /* Do we locate the block behind where we last were? */ 7067 if (rsm && SEQ_LT(start, rsm->r_start)) { 7068 went_back = 1; 7069 TAILQ_FOREACH_REVERSE_FROM(rsm, &bbr->r_ctl.rc_map, bbr_head, r_next) { 7070 if (SEQ_GEQ(start, rsm->r_start) && 7071 SEQ_LT(start, rsm->r_end)) { 7072 goto do_rest_ofb; 7073 } 7074 } 7075 } 7076 start_at_beginning: 7077 went_fwd = 1; 7078 /* 7079 * Ok lets locate the block where this guy is fwd from rsm (if its 7080 * set) 7081 */ 7082 TAILQ_FOREACH_FROM(rsm, &bbr->r_ctl.rc_map, r_next) { 7083 if (SEQ_GEQ(start, rsm->r_start) && 7084 SEQ_LT(start, rsm->r_end)) { 7085 break; 7086 } 7087 } 7088 do_rest_ofb: 7089 if (rsm == NULL) { 7090 /* 7091 * This happens when we get duplicate sack blocks with the 7092 * same end. For example SACK 4: 100 SACK 3: 100 The sort 7093 * will not change there location so we would just start at 7094 * the end of the first one and get lost. 7095 */ 7096 if (tp->t_flags & TF_SENTFIN) { 7097 /* 7098 * Check to see if we have not logged the FIN that 7099 * went out. 7100 */ 7101 nrsm = TAILQ_LAST_FAST(&bbr->r_ctl.rc_map, bbr_sendmap, r_next); 7102 if (nrsm && (nrsm->r_end + 1) == tp->snd_max) { 7103 /* 7104 * Ok we did not get the FIN logged. 7105 */ 7106 nrsm->r_end++; 7107 rsm = nrsm; 7108 goto do_rest_ofb; 7109 } 7110 } 7111 if (times == 1) { 7112 #ifdef BBR_INVARIANTS 7113 panic("tp:%p bbr:%p sack:%p to:%p prsm:%p", 7114 tp, bbr, sack, to, prsm); 7115 #else 7116 goto out; 7117 #endif 7118 } 7119 times++; 7120 BBR_STAT_INC(bbr_sack_proc_restart); 7121 rsm = NULL; 7122 goto start_at_beginning; 7123 } 7124 /* Ok we have an ACK for some piece of rsm */ 7125 if (rsm->r_start != start) { 7126 /* 7127 * Need to split this in two pieces the before and after. 7128 */ 7129 if (bbr_sack_mergable(rsm, start, end)) 7130 nrsm = bbr_alloc_full_limit(bbr); 7131 else 7132 nrsm = bbr_alloc_limit(bbr, BBR_LIMIT_TYPE_SPLIT); 7133 if (nrsm == NULL) { 7134 /* We could not allocate ignore the sack */ 7135 struct sackblk blk; 7136 7137 blk.start = start; 7138 blk.end = end; 7139 sack_filter_reject(&bbr->r_ctl.bbr_sf, &blk); 7140 goto out; 7141 } 7142 bbr_clone_rsm(bbr, nrsm, rsm, start); 7143 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_map, rsm, nrsm, r_next); 7144 if (rsm->r_in_tmap) { 7145 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, rsm, nrsm, r_tnext); 7146 nrsm->r_in_tmap = 1; 7147 } 7148 rsm->r_flags &= (~BBR_HAS_FIN); 7149 rsm = nrsm; 7150 } 7151 if (SEQ_GEQ(end, rsm->r_end)) { 7152 /* 7153 * The end of this block is either beyond this guy or right 7154 * at this guy. 7155 */ 7156 if ((rsm->r_flags & BBR_ACKED) == 0) { 7157 bbr_update_rtt(tp, bbr, rsm, to, cts, BBR_SACKED, 0); 7158 changed += (rsm->r_end - rsm->r_start); 7159 bbr->r_ctl.rc_sacked += (rsm->r_end - rsm->r_start); 7160 bbr_log_sack_passed(tp, bbr, rsm); 7161 if (rsm->r_flags & BBR_MARKED_LOST) { 7162 bbr->r_ctl.rc_lost_bytes -= rsm->r_end - rsm->r_start; 7163 } 7164 /* Is Reordering occuring? */ 7165 if (rsm->r_flags & BBR_SACK_PASSED) { 7166 BBR_STAT_INC(bbr_reorder_seen); 7167 bbr->r_ctl.rc_reorder_ts = cts; 7168 if (rsm->r_flags & BBR_MARKED_LOST) { 7169 bbr->r_ctl.rc_lost -= rsm->r_end - rsm->r_start; 7170 if (SEQ_GT(bbr->r_ctl.rc_lt_lost, bbr->r_ctl.rc_lost)) 7171 /* LT sampling also needs adjustment */ 7172 bbr->r_ctl.rc_lt_lost = bbr->r_ctl.rc_lost; 7173 } 7174 } 7175 rsm->r_flags |= BBR_ACKED; 7176 rsm->r_flags &= ~(BBR_TLP|BBR_WAS_RENEGED|BBR_RXT_CLEARED|BBR_MARKED_LOST); 7177 if (rsm->r_in_tmap) { 7178 TAILQ_REMOVE(&bbr->r_ctl.rc_tmap, rsm, r_tnext); 7179 rsm->r_in_tmap = 0; 7180 } 7181 } 7182 bbr_isit_a_pkt_epoch(bbr, cts, rsm, __LINE__, BBR_SACKED); 7183 if (end == rsm->r_end) { 7184 /* This block only - done */ 7185 goto out; 7186 } 7187 /* There is more not coverend by this rsm move on */ 7188 start = rsm->r_end; 7189 nrsm = TAILQ_NEXT(rsm, r_next); 7190 rsm = nrsm; 7191 times = 0; 7192 goto do_rest_ofb; 7193 } 7194 if (rsm->r_flags & BBR_ACKED) { 7195 /* Been here done that */ 7196 goto out; 7197 } 7198 /* Ok we need to split off this one at the tail */ 7199 if (bbr_sack_mergable(rsm, start, end)) 7200 nrsm = bbr_alloc_full_limit(bbr); 7201 else 7202 nrsm = bbr_alloc_limit(bbr, BBR_LIMIT_TYPE_SPLIT); 7203 if (nrsm == NULL) { 7204 /* failed XXXrrs what can we do but loose the sack info? */ 7205 struct sackblk blk; 7206 7207 blk.start = start; 7208 blk.end = end; 7209 sack_filter_reject(&bbr->r_ctl.bbr_sf, &blk); 7210 goto out; 7211 } 7212 /* Clone it */ 7213 bbr_clone_rsm(bbr, nrsm, rsm, end); 7214 /* The sack block does not cover this guy fully */ 7215 rsm->r_flags &= (~BBR_HAS_FIN); 7216 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_map, rsm, nrsm, r_next); 7217 if (rsm->r_in_tmap) { 7218 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, rsm, nrsm, r_tnext); 7219 nrsm->r_in_tmap = 1; 7220 } 7221 nrsm->r_dupack = 0; 7222 bbr_update_rtt(tp, bbr, rsm, to, cts, BBR_SACKED, 0); 7223 bbr_isit_a_pkt_epoch(bbr, cts, rsm, __LINE__, BBR_SACKED); 7224 changed += (rsm->r_end - rsm->r_start); 7225 bbr->r_ctl.rc_sacked += (rsm->r_end - rsm->r_start); 7226 bbr_log_sack_passed(tp, bbr, rsm); 7227 /* Is Reordering occuring? */ 7228 if (rsm->r_flags & BBR_MARKED_LOST) { 7229 bbr->r_ctl.rc_lost_bytes -= rsm->r_end - rsm->r_start; 7230 } 7231 if (rsm->r_flags & BBR_SACK_PASSED) { 7232 BBR_STAT_INC(bbr_reorder_seen); 7233 bbr->r_ctl.rc_reorder_ts = cts; 7234 if (rsm->r_flags & BBR_MARKED_LOST) { 7235 bbr->r_ctl.rc_lost -= rsm->r_end - rsm->r_start; 7236 if (SEQ_GT(bbr->r_ctl.rc_lt_lost, bbr->r_ctl.rc_lost)) 7237 /* LT sampling also needs adjustment */ 7238 bbr->r_ctl.rc_lt_lost = bbr->r_ctl.rc_lost; 7239 } 7240 } 7241 rsm->r_flags &= ~(BBR_TLP|BBR_WAS_RENEGED|BBR_RXT_CLEARED|BBR_MARKED_LOST); 7242 rsm->r_flags |= BBR_ACKED; 7243 if (rsm->r_in_tmap) { 7244 TAILQ_REMOVE(&bbr->r_ctl.rc_tmap, rsm, r_tnext); 7245 rsm->r_in_tmap = 0; 7246 } 7247 out: 7248 if (rsm && (rsm->r_flags & BBR_ACKED)) { 7249 /* 7250 * Now can we merge this newly acked 7251 * block with either the previous or 7252 * next block? 7253 */ 7254 nrsm = TAILQ_NEXT(rsm, r_next); 7255 if (nrsm && 7256 (nrsm->r_flags & BBR_ACKED)) { 7257 /* yep this and next can be merged */ 7258 rsm = bbr_merge_rsm(bbr, rsm, nrsm); 7259 } 7260 /* Now what about the previous? */ 7261 nrsm = TAILQ_PREV(rsm, bbr_head, r_next); 7262 if (nrsm && 7263 (nrsm->r_flags & BBR_ACKED)) { 7264 /* yep the previous and this can be merged */ 7265 rsm = bbr_merge_rsm(bbr, nrsm, rsm); 7266 } 7267 } 7268 if (used_ref == 0) { 7269 BBR_STAT_INC(bbr_sack_proc_all); 7270 } else { 7271 BBR_STAT_INC(bbr_sack_proc_short); 7272 } 7273 if (went_fwd && went_back) { 7274 BBR_STAT_INC(bbr_sack_search_both); 7275 } else if (went_fwd) { 7276 BBR_STAT_INC(bbr_sack_search_fwd); 7277 } else if (went_back) { 7278 BBR_STAT_INC(bbr_sack_search_back); 7279 } 7280 /* Save off where the next seq is */ 7281 if (rsm) 7282 bbr->r_ctl.rc_sacklast = TAILQ_NEXT(rsm, r_next); 7283 else 7284 bbr->r_ctl.rc_sacklast = NULL; 7285 *prsm = rsm; 7286 return (changed); 7287 } 7288 7289 static void inline 7290 bbr_peer_reneges(struct tcp_bbr *bbr, struct bbr_sendmap *rsm, tcp_seq th_ack) 7291 { 7292 struct bbr_sendmap *tmap; 7293 7294 BBR_STAT_INC(bbr_reneges_seen); 7295 tmap = NULL; 7296 while (rsm && (rsm->r_flags & BBR_ACKED)) { 7297 /* Its no longer sacked, mark it so */ 7298 uint32_t oflags; 7299 bbr->r_ctl.rc_sacked -= (rsm->r_end - rsm->r_start); 7300 #ifdef BBR_INVARIANTS 7301 if (rsm->r_in_tmap) { 7302 panic("bbr:%p rsm:%p flags:0x%x in tmap?", 7303 bbr, rsm, rsm->r_flags); 7304 } 7305 #endif 7306 oflags = rsm->r_flags; 7307 if (rsm->r_flags & BBR_MARKED_LOST) { 7308 bbr->r_ctl.rc_lost -= rsm->r_end - rsm->r_start; 7309 bbr->r_ctl.rc_lost_bytes -= rsm->r_end - rsm->r_start; 7310 if (SEQ_GT(bbr->r_ctl.rc_lt_lost, bbr->r_ctl.rc_lost)) 7311 /* LT sampling also needs adjustment */ 7312 bbr->r_ctl.rc_lt_lost = bbr->r_ctl.rc_lost; 7313 } 7314 rsm->r_flags &= ~(BBR_ACKED | BBR_SACK_PASSED | BBR_WAS_SACKPASS | BBR_MARKED_LOST); 7315 rsm->r_flags |= BBR_WAS_RENEGED; 7316 rsm->r_flags |= BBR_RXT_CLEARED; 7317 bbr_log_type_rsmclear(bbr, bbr->r_ctl.rc_rcvtime, rsm, oflags, __LINE__); 7318 /* Rebuild it into our tmap */ 7319 if (tmap == NULL) { 7320 TAILQ_INSERT_HEAD(&bbr->r_ctl.rc_tmap, rsm, r_tnext); 7321 tmap = rsm; 7322 } else { 7323 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, tmap, rsm, r_tnext); 7324 tmap = rsm; 7325 } 7326 tmap->r_in_tmap = 1; 7327 /* 7328 * XXXrrs Delivered? Should we do anything here? 7329 * 7330 * Of course we don't on a rxt timeout so maybe its ok that 7331 * we don't? 7332 * 7333 * For now lets not. 7334 */ 7335 rsm = TAILQ_NEXT(rsm, r_next); 7336 } 7337 /* 7338 * Now lets possibly clear the sack filter so we start recognizing 7339 * sacks that cover this area. 7340 */ 7341 sack_filter_clear(&bbr->r_ctl.bbr_sf, th_ack); 7342 } 7343 7344 static void 7345 bbr_log_syn(struct tcpcb *tp, struct tcpopt *to) 7346 { 7347 struct tcp_bbr *bbr; 7348 struct bbr_sendmap *rsm; 7349 uint32_t cts; 7350 7351 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 7352 cts = bbr->r_ctl.rc_rcvtime; 7353 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map); 7354 if (rsm && (rsm->r_flags & BBR_HAS_SYN)) { 7355 if ((rsm->r_end - rsm->r_start) <= 1) { 7356 /* Log out the SYN completely */ 7357 bbr->r_ctl.rc_holes_rxt -= rsm->r_rtr_bytes; 7358 rsm->r_rtr_bytes = 0; 7359 TAILQ_REMOVE(&bbr->r_ctl.rc_map, rsm, r_next); 7360 if (rsm->r_in_tmap) { 7361 TAILQ_REMOVE(&bbr->r_ctl.rc_tmap, rsm, r_tnext); 7362 rsm->r_in_tmap = 0; 7363 } 7364 if (bbr->r_ctl.rc_next == rsm) { 7365 /* scoot along the marker */ 7366 bbr->r_ctl.rc_next = TAILQ_FIRST(&bbr->r_ctl.rc_map); 7367 } 7368 if (to != NULL) 7369 bbr_update_rtt(tp, bbr, rsm, to, cts, BBR_CUM_ACKED, 0); 7370 bbr_free(bbr, rsm); 7371 } else { 7372 /* There is more (Fast open)? strip out SYN. */ 7373 rsm->r_flags &= ~BBR_HAS_SYN; 7374 rsm->r_start++; 7375 } 7376 } 7377 } 7378 7379 /* 7380 * Returns the number of bytes that were 7381 * acknowledged by SACK blocks. 7382 */ 7383 7384 static uint32_t 7385 bbr_log_ack(struct tcpcb *tp, struct tcpopt *to, struct tcphdr *th, 7386 uint32_t *prev_acked) 7387 { 7388 uint32_t changed, last_seq, entered_recovery = 0; 7389 struct tcp_bbr *bbr; 7390 struct bbr_sendmap *rsm; 7391 struct sackblk sack, sack_blocks[TCP_MAX_SACK + 1]; 7392 register uint32_t th_ack; 7393 int32_t i, j, k, new_sb, num_sack_blks = 0; 7394 uint32_t cts, acked, ack_point, sack_changed = 0; 7395 uint32_t p_maxseg, maxseg, p_acked = 0; 7396 7397 INP_WLOCK_ASSERT(tp->t_inpcb); 7398 if (th->th_flags & TH_RST) { 7399 /* We don't log resets */ 7400 return (0); 7401 } 7402 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 7403 cts = bbr->r_ctl.rc_rcvtime; 7404 7405 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map); 7406 changed = 0; 7407 maxseg = tp->t_maxseg - bbr->rc_last_options; 7408 p_maxseg = min(bbr->r_ctl.rc_pace_max_segs, maxseg); 7409 th_ack = th->th_ack; 7410 if (SEQ_GT(th_ack, tp->snd_una)) { 7411 acked = th_ack - tp->snd_una; 7412 bbr_log_progress_event(bbr, tp, ticks, PROGRESS_UPDATE, __LINE__); 7413 bbr->rc_tp->t_acktime = ticks; 7414 } else 7415 acked = 0; 7416 if (SEQ_LEQ(th_ack, tp->snd_una)) { 7417 /* Only sent here for sack processing */ 7418 goto proc_sack; 7419 } 7420 if (rsm && SEQ_GT(th_ack, rsm->r_start)) { 7421 changed = th_ack - rsm->r_start; 7422 } else if ((rsm == NULL) && ((th_ack - 1) == tp->iss)) { 7423 /* 7424 * For the SYN incoming case we will not have called 7425 * tcp_output for the sending of the SYN, so there will be 7426 * no map. All other cases should probably be a panic. 7427 */ 7428 if ((to->to_flags & TOF_TS) && (to->to_tsecr != 0)) { 7429 /* 7430 * We have a timestamp that can be used to generate 7431 * an initial RTT. 7432 */ 7433 uint32_t ts, now, rtt; 7434 7435 ts = bbr_ts_convert(to->to_tsecr); 7436 now = bbr_ts_convert(tcp_tv_to_mssectick(&bbr->rc_tv)); 7437 rtt = now - ts; 7438 if (rtt < 1) 7439 rtt = 1; 7440 bbr_log_type_bbrrttprop(bbr, rtt, 7441 tp->iss, 0, cts, 7442 BBR_RTT_BY_TIMESTAMP, tp->iss, 0); 7443 apply_filter_min_small(&bbr->r_ctl.rc_rttprop, rtt, cts); 7444 changed = 1; 7445 bbr->r_wanted_output = 1; 7446 goto out; 7447 } 7448 goto proc_sack; 7449 } else if (rsm == NULL) { 7450 goto out; 7451 } 7452 if (changed) { 7453 /* 7454 * The ACK point is advancing to th_ack, we must drop off 7455 * the packets in the rack log and calculate any eligble 7456 * RTT's. 7457 */ 7458 bbr->r_wanted_output = 1; 7459 more: 7460 if (rsm == NULL) { 7461 if (tp->t_flags & TF_SENTFIN) { 7462 /* if we send a FIN we will not hav a map */ 7463 goto proc_sack; 7464 } 7465 #ifdef BBR_INVARIANTS 7466 panic("No rack map tp:%p for th:%p state:%d bbr:%p snd_una:%u snd_max:%u chg:%d\n", 7467 tp, 7468 th, tp->t_state, bbr, 7469 tp->snd_una, tp->snd_max, changed); 7470 #endif 7471 goto proc_sack; 7472 } 7473 } 7474 if (SEQ_LT(th_ack, rsm->r_start)) { 7475 /* Huh map is missing this */ 7476 #ifdef BBR_INVARIANTS 7477 printf("Rack map starts at r_start:%u for th_ack:%u huh? ts:%d rs:%d bbr:%p\n", 7478 rsm->r_start, 7479 th_ack, tp->t_state, 7480 bbr->r_state, bbr); 7481 panic("th-ack is bad bbr:%p tp:%p", bbr, tp); 7482 #endif 7483 goto proc_sack; 7484 } else if (th_ack == rsm->r_start) { 7485 /* None here to ack */ 7486 goto proc_sack; 7487 } 7488 /* 7489 * Clear the dup ack counter, it will 7490 * either be freed or if there is some 7491 * remaining we need to start it at zero. 7492 */ 7493 rsm->r_dupack = 0; 7494 /* Now do we consume the whole thing? */ 7495 if (SEQ_GEQ(th_ack, rsm->r_end)) { 7496 /* Its all consumed. */ 7497 uint32_t left; 7498 7499 if (rsm->r_flags & BBR_ACKED) { 7500 /* 7501 * It was acked on the scoreboard -- remove it from 7502 * total 7503 */ 7504 p_acked += (rsm->r_end - rsm->r_start); 7505 bbr->r_ctl.rc_sacked -= (rsm->r_end - rsm->r_start); 7506 if (bbr->r_ctl.rc_sacked == 0) 7507 bbr->r_ctl.rc_sacklast = NULL; 7508 } else { 7509 bbr_update_rtt(tp, bbr, rsm, to, cts, BBR_CUM_ACKED, th_ack); 7510 if (rsm->r_flags & BBR_MARKED_LOST) { 7511 bbr->r_ctl.rc_lost_bytes -= rsm->r_end - rsm->r_start; 7512 } 7513 if (rsm->r_flags & BBR_SACK_PASSED) { 7514 /* 7515 * There are acked segments ACKED on the 7516 * scoreboard further up. We are seeing 7517 * reordering. 7518 */ 7519 BBR_STAT_INC(bbr_reorder_seen); 7520 bbr->r_ctl.rc_reorder_ts = cts; 7521 if (rsm->r_flags & BBR_MARKED_LOST) { 7522 bbr->r_ctl.rc_lost -= rsm->r_end - rsm->r_start; 7523 if (SEQ_GT(bbr->r_ctl.rc_lt_lost, bbr->r_ctl.rc_lost)) 7524 /* LT sampling also needs adjustment */ 7525 bbr->r_ctl.rc_lt_lost = bbr->r_ctl.rc_lost; 7526 } 7527 } 7528 rsm->r_flags &= ~BBR_MARKED_LOST; 7529 } 7530 bbr->r_ctl.rc_holes_rxt -= rsm->r_rtr_bytes; 7531 rsm->r_rtr_bytes = 0; 7532 TAILQ_REMOVE(&bbr->r_ctl.rc_map, rsm, r_next); 7533 if (rsm->r_in_tmap) { 7534 TAILQ_REMOVE(&bbr->r_ctl.rc_tmap, rsm, r_tnext); 7535 rsm->r_in_tmap = 0; 7536 } 7537 if (bbr->r_ctl.rc_next == rsm) { 7538 /* scoot along the marker */ 7539 bbr->r_ctl.rc_next = TAILQ_FIRST(&bbr->r_ctl.rc_map); 7540 } 7541 bbr_isit_a_pkt_epoch(bbr, cts, rsm, __LINE__, BBR_CUM_ACKED); 7542 /* Adjust the packet counts */ 7543 left = th_ack - rsm->r_end; 7544 /* Free back to zone */ 7545 bbr_free(bbr, rsm); 7546 if (left) { 7547 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map); 7548 goto more; 7549 } 7550 goto proc_sack; 7551 } 7552 if (rsm->r_flags & BBR_ACKED) { 7553 /* 7554 * It was acked on the scoreboard -- remove it from total 7555 * for the part being cum-acked. 7556 */ 7557 p_acked += (rsm->r_end - rsm->r_start); 7558 bbr->r_ctl.rc_sacked -= (th_ack - rsm->r_start); 7559 if (bbr->r_ctl.rc_sacked == 0) 7560 bbr->r_ctl.rc_sacklast = NULL; 7561 } else { 7562 /* 7563 * It was acked up to th_ack point for the first time 7564 */ 7565 struct bbr_sendmap lrsm; 7566 7567 memcpy(&lrsm, rsm, sizeof(struct bbr_sendmap)); 7568 lrsm.r_end = th_ack; 7569 bbr_update_rtt(tp, bbr, &lrsm, to, cts, BBR_CUM_ACKED, th_ack); 7570 } 7571 if ((rsm->r_flags & BBR_MARKED_LOST) && 7572 ((rsm->r_flags & BBR_ACKED) == 0)) { 7573 /* 7574 * It was marked lost and partly ack'd now 7575 * for the first time. We lower the rc_lost_bytes 7576 * and still leave it MARKED. 7577 */ 7578 bbr->r_ctl.rc_lost_bytes -= th_ack - rsm->r_start; 7579 } 7580 bbr_isit_a_pkt_epoch(bbr, cts, rsm, __LINE__, BBR_CUM_ACKED); 7581 bbr->r_ctl.rc_holes_rxt -= rsm->r_rtr_bytes; 7582 rsm->r_rtr_bytes = 0; 7583 /* adjust packet count */ 7584 rsm->r_start = th_ack; 7585 proc_sack: 7586 /* Check for reneging */ 7587 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map); 7588 if (rsm && (rsm->r_flags & BBR_ACKED) && (th_ack == rsm->r_start)) { 7589 /* 7590 * The peer has moved snd_una up to the edge of this send, 7591 * i.e. one that it had previously acked. The only way that 7592 * can be true if the peer threw away data (space issues) 7593 * that it had previously sacked (else it would have given 7594 * us snd_una up to (rsm->r_end). We need to undo the acked 7595 * markings here. 7596 * 7597 * Note we have to look to make sure th_ack is our 7598 * rsm->r_start in case we get an old ack where th_ack is 7599 * behind snd_una. 7600 */ 7601 bbr_peer_reneges(bbr, rsm, th->th_ack); 7602 } 7603 if ((to->to_flags & TOF_SACK) == 0) { 7604 /* We are done nothing left to log */ 7605 goto out; 7606 } 7607 rsm = TAILQ_LAST_FAST(&bbr->r_ctl.rc_map, bbr_sendmap, r_next); 7608 if (rsm) { 7609 last_seq = rsm->r_end; 7610 } else { 7611 last_seq = tp->snd_max; 7612 } 7613 /* Sack block processing */ 7614 if (SEQ_GT(th_ack, tp->snd_una)) 7615 ack_point = th_ack; 7616 else 7617 ack_point = tp->snd_una; 7618 for (i = 0; i < to->to_nsacks; i++) { 7619 bcopy((to->to_sacks + i * TCPOLEN_SACK), 7620 &sack, sizeof(sack)); 7621 sack.start = ntohl(sack.start); 7622 sack.end = ntohl(sack.end); 7623 if (SEQ_GT(sack.end, sack.start) && 7624 SEQ_GT(sack.start, ack_point) && 7625 SEQ_LT(sack.start, tp->snd_max) && 7626 SEQ_GT(sack.end, ack_point) && 7627 SEQ_LEQ(sack.end, tp->snd_max)) { 7628 if ((bbr->r_ctl.rc_num_small_maps_alloced > bbr_sack_block_limit) && 7629 (SEQ_LT(sack.end, last_seq)) && 7630 ((sack.end - sack.start) < (p_maxseg / 8))) { 7631 /* 7632 * Not the last piece and its smaller than 7633 * 1/8th of a p_maxseg. We ignore this. 7634 */ 7635 BBR_STAT_INC(bbr_runt_sacks); 7636 continue; 7637 } 7638 sack_blocks[num_sack_blks] = sack; 7639 num_sack_blks++; 7640 #ifdef NETFLIX_STATS 7641 } else if (SEQ_LEQ(sack.start, th_ack) && 7642 SEQ_LEQ(sack.end, th_ack)) { 7643 /* 7644 * Its a D-SACK block. 7645 */ 7646 tcp_record_dsack(sack.start, sack.end); 7647 #endif 7648 } 7649 } 7650 if (num_sack_blks == 0) 7651 goto out; 7652 /* 7653 * Sort the SACK blocks so we can update the rack scoreboard with 7654 * just one pass. 7655 */ 7656 new_sb = sack_filter_blks(&bbr->r_ctl.bbr_sf, sack_blocks, 7657 num_sack_blks, th->th_ack); 7658 ctf_log_sack_filter(bbr->rc_tp, new_sb, sack_blocks); 7659 BBR_STAT_ADD(bbr_sack_blocks, num_sack_blks); 7660 BBR_STAT_ADD(bbr_sack_blocks_skip, (num_sack_blks - new_sb)); 7661 num_sack_blks = new_sb; 7662 if (num_sack_blks < 2) { 7663 goto do_sack_work; 7664 } 7665 /* Sort the sacks */ 7666 for (i = 0; i < num_sack_blks; i++) { 7667 for (j = i + 1; j < num_sack_blks; j++) { 7668 if (SEQ_GT(sack_blocks[i].end, sack_blocks[j].end)) { 7669 sack = sack_blocks[i]; 7670 sack_blocks[i] = sack_blocks[j]; 7671 sack_blocks[j] = sack; 7672 } 7673 } 7674 } 7675 /* 7676 * Now are any of the sack block ends the same (yes some 7677 * implememtations send these)? 7678 */ 7679 again: 7680 if (num_sack_blks > 1) { 7681 for (i = 0; i < num_sack_blks; i++) { 7682 for (j = i + 1; j < num_sack_blks; j++) { 7683 if (sack_blocks[i].end == sack_blocks[j].end) { 7684 /* 7685 * Ok these two have the same end we 7686 * want the smallest end and then 7687 * throw away the larger and start 7688 * again. 7689 */ 7690 if (SEQ_LT(sack_blocks[j].start, sack_blocks[i].start)) { 7691 /* 7692 * The second block covers 7693 * more area use that 7694 */ 7695 sack_blocks[i].start = sack_blocks[j].start; 7696 } 7697 /* 7698 * Now collapse out the dup-sack and 7699 * lower the count 7700 */ 7701 for (k = (j + 1); k < num_sack_blks; k++) { 7702 sack_blocks[j].start = sack_blocks[k].start; 7703 sack_blocks[j].end = sack_blocks[k].end; 7704 j++; 7705 } 7706 num_sack_blks--; 7707 goto again; 7708 } 7709 } 7710 } 7711 } 7712 do_sack_work: 7713 rsm = bbr->r_ctl.rc_sacklast; 7714 for (i = 0; i < num_sack_blks; i++) { 7715 acked = bbr_proc_sack_blk(tp, bbr, &sack_blocks[i], to, &rsm, cts); 7716 if (acked) { 7717 bbr->r_wanted_output = 1; 7718 changed += acked; 7719 sack_changed += acked; 7720 } 7721 } 7722 out: 7723 *prev_acked = p_acked; 7724 if ((sack_changed) && (!IN_RECOVERY(tp->t_flags))) { 7725 /* 7726 * Ok we have a high probability that we need to go in to 7727 * recovery since we have data sack'd 7728 */ 7729 struct bbr_sendmap *rsm; 7730 7731 rsm = bbr_check_recovery_mode(tp, bbr, cts); 7732 if (rsm) { 7733 /* Enter recovery */ 7734 entered_recovery = 1; 7735 bbr->r_wanted_output = 1; 7736 /* 7737 * When we enter recovery we need to assure we send 7738 * one packet. 7739 */ 7740 if (bbr->r_ctl.rc_resend == NULL) { 7741 bbr->r_ctl.rc_resend = rsm; 7742 } 7743 } 7744 } 7745 if (IN_RECOVERY(tp->t_flags) && (entered_recovery == 0)) { 7746 /* 7747 * See if we need to rack-retransmit anything if so set it 7748 * up as the thing to resend assuming something else is not 7749 * already in that position. 7750 */ 7751 if (bbr->r_ctl.rc_resend == NULL) { 7752 bbr->r_ctl.rc_resend = bbr_check_recovery_mode(tp, bbr, cts); 7753 } 7754 } 7755 /* 7756 * We return the amount that changed via sack, this is used by the 7757 * ack-received code to augment what was changed between th_ack <-> 7758 * snd_una. 7759 */ 7760 return (sack_changed); 7761 } 7762 7763 static void 7764 bbr_strike_dupack(struct tcp_bbr *bbr) 7765 { 7766 struct bbr_sendmap *rsm; 7767 7768 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_tmap); 7769 if (rsm && (rsm->r_dupack < 0xff)) { 7770 rsm->r_dupack++; 7771 if (rsm->r_dupack >= DUP_ACK_THRESHOLD) 7772 bbr->r_wanted_output = 1; 7773 } 7774 } 7775 7776 /* 7777 * Return value of 1, we do not need to call bbr_process_data(). 7778 * return value of 0, bbr_process_data can be called. 7779 * For ret_val if its 0 the TCB is locked and valid, if its non-zero 7780 * its unlocked and probably unsafe to touch the TCB. 7781 */ 7782 static int 7783 bbr_process_ack(struct mbuf *m, struct tcphdr *th, struct socket *so, 7784 struct tcpcb *tp, struct tcpopt *to, 7785 uint32_t tiwin, int32_t tlen, 7786 int32_t * ofia, int32_t thflags, int32_t * ret_val) 7787 { 7788 int32_t ourfinisacked = 0; 7789 int32_t acked_amount; 7790 uint16_t nsegs; 7791 int32_t acked; 7792 uint32_t lost, sack_changed = 0; 7793 struct mbuf *mfree; 7794 struct tcp_bbr *bbr; 7795 uint32_t prev_acked = 0; 7796 7797 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 7798 lost = bbr->r_ctl.rc_lost; 7799 nsegs = max(1, m->m_pkthdr.lro_nsegs); 7800 if (SEQ_GT(th->th_ack, tp->snd_max)) { 7801 ctf_do_dropafterack(m, tp, th, thflags, tlen, ret_val); 7802 bbr->r_wanted_output = 1; 7803 return (1); 7804 } 7805 if (SEQ_GEQ(th->th_ack, tp->snd_una) || to->to_nsacks) { 7806 /* Process the ack */ 7807 if (bbr->rc_in_persist) 7808 tp->t_rxtshift = 0; 7809 if ((th->th_ack == tp->snd_una) && (tiwin == tp->snd_wnd)) 7810 bbr_strike_dupack(bbr); 7811 sack_changed = bbr_log_ack(tp, to, th, &prev_acked); 7812 } 7813 bbr_lt_bw_sampling(bbr, bbr->r_ctl.rc_rcvtime, (bbr->r_ctl.rc_lost > lost)); 7814 if (__predict_false(SEQ_LEQ(th->th_ack, tp->snd_una))) { 7815 /* 7816 * Old ack, behind the last one rcv'd or a duplicate ack 7817 * with SACK info. 7818 */ 7819 if (th->th_ack == tp->snd_una) { 7820 bbr_ack_received(tp, bbr, th, 0, sack_changed, prev_acked, __LINE__, 0); 7821 if (bbr->r_state == TCPS_SYN_SENT) { 7822 /* 7823 * Special case on where we sent SYN. When 7824 * the SYN-ACK is processed in syn_sent 7825 * state it bumps the snd_una. This causes 7826 * us to hit here even though we did ack 1 7827 * byte. 7828 * 7829 * Go through the nothing left case so we 7830 * send data. 7831 */ 7832 goto nothing_left; 7833 } 7834 } 7835 return (0); 7836 } 7837 /* 7838 * If we reach this point, ACK is not a duplicate, i.e., it ACKs 7839 * something we sent. 7840 */ 7841 if (tp->t_flags & TF_NEEDSYN) { 7842 /* 7843 * T/TCP: Connection was half-synchronized, and our SYN has 7844 * been ACK'd (so connection is now fully synchronized). Go 7845 * to non-starred state, increment snd_una for ACK of SYN, 7846 * and check if we can do window scaling. 7847 */ 7848 tp->t_flags &= ~TF_NEEDSYN; 7849 tp->snd_una++; 7850 /* Do window scaling? */ 7851 if ((tp->t_flags & (TF_RCVD_SCALE | TF_REQ_SCALE)) == 7852 (TF_RCVD_SCALE | TF_REQ_SCALE)) { 7853 tp->rcv_scale = tp->request_r_scale; 7854 /* Send window already scaled. */ 7855 } 7856 } 7857 INP_WLOCK_ASSERT(tp->t_inpcb); 7858 7859 acked = BYTES_THIS_ACK(tp, th); 7860 KMOD_TCPSTAT_ADD(tcps_rcvackpack, (int)nsegs); 7861 KMOD_TCPSTAT_ADD(tcps_rcvackbyte, acked); 7862 7863 /* 7864 * If we just performed our first retransmit, and the ACK arrives 7865 * within our recovery window, then it was a mistake to do the 7866 * retransmit in the first place. Recover our original cwnd and 7867 * ssthresh, and proceed to transmit where we left off. 7868 */ 7869 if (tp->t_flags & TF_PREVVALID) { 7870 tp->t_flags &= ~TF_PREVVALID; 7871 if (tp->t_rxtshift == 1 && 7872 (int)(ticks - tp->t_badrxtwin) < 0) 7873 bbr_cong_signal(tp, th, CC_RTO_ERR, NULL); 7874 } 7875 SOCKBUF_LOCK(&so->so_snd); 7876 acked_amount = min(acked, (int)sbavail(&so->so_snd)); 7877 tp->snd_wnd -= acked_amount; 7878 mfree = sbcut_locked(&so->so_snd, acked_amount); 7879 /* NB: sowwakeup_locked() does an implicit unlock. */ 7880 sowwakeup_locked(so); 7881 m_freem(mfree); 7882 if (SEQ_GT(th->th_ack, tp->snd_una)) { 7883 bbr_collapse_rtt(tp, bbr, TCP_REXMTVAL(tp)); 7884 } 7885 tp->snd_una = th->th_ack; 7886 bbr_ack_received(tp, bbr, th, acked, sack_changed, prev_acked, __LINE__, (bbr->r_ctl.rc_lost - lost)); 7887 if (IN_RECOVERY(tp->t_flags)) { 7888 if (SEQ_LT(th->th_ack, tp->snd_recover) && 7889 (SEQ_LT(th->th_ack, tp->snd_max))) { 7890 tcp_bbr_partialack(tp); 7891 } else { 7892 bbr_post_recovery(tp); 7893 } 7894 } 7895 if (SEQ_GT(tp->snd_una, tp->snd_recover)) { 7896 tp->snd_recover = tp->snd_una; 7897 } 7898 if (SEQ_LT(tp->snd_nxt, tp->snd_max)) { 7899 tp->snd_nxt = tp->snd_max; 7900 } 7901 if (tp->snd_una == tp->snd_max) { 7902 /* Nothing left outstanding */ 7903 nothing_left: 7904 bbr_log_progress_event(bbr, tp, ticks, PROGRESS_CLEAR, __LINE__); 7905 if (sbavail(&tp->t_inpcb->inp_socket->so_snd) == 0) 7906 bbr->rc_tp->t_acktime = 0; 7907 if ((sbused(&so->so_snd) == 0) && 7908 (tp->t_flags & TF_SENTFIN)) { 7909 ourfinisacked = 1; 7910 } 7911 bbr_timer_cancel(bbr, __LINE__, bbr->r_ctl.rc_rcvtime); 7912 if (bbr->rc_in_persist == 0) { 7913 bbr->r_ctl.rc_went_idle_time = bbr->r_ctl.rc_rcvtime; 7914 } 7915 sack_filter_clear(&bbr->r_ctl.bbr_sf, tp->snd_una); 7916 bbr_log_ack_clear(bbr, bbr->r_ctl.rc_rcvtime); 7917 /* 7918 * We invalidate the last ack here since we 7919 * don't want to transfer forward the time 7920 * for our sum's calculations. 7921 */ 7922 if ((tp->t_state >= TCPS_FIN_WAIT_1) && 7923 (sbavail(&so->so_snd) == 0) && 7924 (tp->t_flags2 & TF2_DROP_AF_DATA)) { 7925 /* 7926 * The socket was gone and the peer sent data, time 7927 * to reset him. 7928 */ 7929 *ret_val = 1; 7930 tcp_log_end_status(tp, TCP_EI_STATUS_DATA_A_CLOSE); 7931 /* tcp_close will kill the inp pre-log the Reset */ 7932 tcp_log_end_status(tp, TCP_EI_STATUS_SERVER_RST); 7933 tp = tcp_close(tp); 7934 ctf_do_dropwithreset(m, tp, th, BANDLIM_UNLIMITED, tlen); 7935 BBR_STAT_INC(bbr_dropped_af_data); 7936 return (1); 7937 } 7938 /* Set need output so persist might get set */ 7939 bbr->r_wanted_output = 1; 7940 } 7941 if (ofia) 7942 *ofia = ourfinisacked; 7943 return (0); 7944 } 7945 7946 static void 7947 bbr_enter_persist(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts, int32_t line) 7948 { 7949 if (bbr->rc_in_persist == 0) { 7950 bbr_timer_cancel(bbr, __LINE__, cts); 7951 bbr->r_ctl.rc_last_delay_val = 0; 7952 tp->t_rxtshift = 0; 7953 bbr->rc_in_persist = 1; 7954 bbr->r_ctl.rc_went_idle_time = cts; 7955 /* We should be capped when rw went to 0 but just in case */ 7956 bbr_log_type_pesist(bbr, cts, 0, line, 1); 7957 /* Time freezes for the state, so do the accounting now */ 7958 if (SEQ_GT(cts, bbr->r_ctl.rc_bbr_state_time)) { 7959 uint32_t time_in; 7960 7961 time_in = cts - bbr->r_ctl.rc_bbr_state_time; 7962 if (bbr->rc_bbr_state == BBR_STATE_PROBE_BW) { 7963 int32_t idx; 7964 7965 idx = bbr_state_val(bbr); 7966 counter_u64_add(bbr_state_time[(idx + 5)], time_in); 7967 } else { 7968 counter_u64_add(bbr_state_time[bbr->rc_bbr_state], time_in); 7969 } 7970 } 7971 bbr->r_ctl.rc_bbr_state_time = cts; 7972 } 7973 } 7974 7975 static void 7976 bbr_restart_after_idle(struct tcp_bbr *bbr, uint32_t cts, uint32_t idle_time) 7977 { 7978 /* 7979 * Note that if idle time does not exceed our 7980 * threshold, we do nothing continuing the state 7981 * transitions we were last walking through. 7982 */ 7983 if (idle_time >= bbr_idle_restart_threshold) { 7984 if (bbr->rc_use_idle_restart) { 7985 bbr->rc_bbr_state = BBR_STATE_IDLE_EXIT; 7986 /* 7987 * Set our target using BBR_UNIT, so 7988 * we increase at a dramatic rate but 7989 * we stop when we get the pipe 7990 * full again for our current b/w estimate. 7991 */ 7992 bbr->r_ctl.rc_bbr_hptsi_gain = BBR_UNIT; 7993 bbr->r_ctl.rc_bbr_cwnd_gain = BBR_UNIT; 7994 bbr_set_state_target(bbr, __LINE__); 7995 /* Now setup our gains to ramp up */ 7996 bbr->r_ctl.rc_bbr_hptsi_gain = bbr->r_ctl.rc_startup_pg; 7997 bbr->r_ctl.rc_bbr_cwnd_gain = bbr->r_ctl.rc_startup_pg; 7998 bbr_log_type_statechange(bbr, cts, __LINE__); 7999 } else if (bbr->rc_bbr_state == BBR_STATE_PROBE_BW) { 8000 bbr_substate_change(bbr, cts, __LINE__, 1); 8001 } 8002 } 8003 } 8004 8005 static void 8006 bbr_exit_persist(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts, int32_t line) 8007 { 8008 uint32_t idle_time; 8009 8010 if (bbr->rc_in_persist == 0) 8011 return; 8012 idle_time = bbr_calc_time(cts, bbr->r_ctl.rc_went_idle_time); 8013 bbr->rc_in_persist = 0; 8014 bbr->rc_hit_state_1 = 0; 8015 bbr->r_ctl.rc_del_time = cts; 8016 /* 8017 * We invalidate the last ack here since we 8018 * don't want to transfer forward the time 8019 * for our sum's calculations. 8020 */ 8021 if (bbr->rc_inp->inp_in_hpts) { 8022 tcp_hpts_remove(bbr->rc_inp, HPTS_REMOVE_OUTPUT); 8023 bbr->rc_timer_first = 0; 8024 bbr->r_ctl.rc_hpts_flags = 0; 8025 bbr->r_ctl.rc_last_delay_val = 0; 8026 bbr->r_ctl.rc_hptsi_agg_delay = 0; 8027 bbr->r_agg_early_set = 0; 8028 bbr->r_ctl.rc_agg_early = 0; 8029 } 8030 bbr_log_type_pesist(bbr, cts, idle_time, line, 0); 8031 if (idle_time >= bbr_rtt_probe_time) { 8032 /* 8033 * This qualifies as a RTT_PROBE session since we drop the 8034 * data outstanding to nothing and waited more than 8035 * bbr_rtt_probe_time. 8036 */ 8037 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_PERSIST, 0); 8038 bbr->r_ctl.last_in_probertt = bbr->r_ctl.rc_rtt_shrinks = cts; 8039 } 8040 tp->t_rxtshift = 0; 8041 /* 8042 * If in probeBW and we have persisted more than an RTT lets do 8043 * special handling. 8044 */ 8045 /* Force a time based epoch */ 8046 bbr_set_epoch(bbr, cts, __LINE__); 8047 /* 8048 * Setup the lost so we don't count anything against the guy 8049 * we have been stuck with during persists. 8050 */ 8051 bbr->r_ctl.bbr_lost_at_state = bbr->r_ctl.rc_lost; 8052 /* Time un-freezes for the state */ 8053 bbr->r_ctl.rc_bbr_state_time = cts; 8054 if ((bbr->rc_bbr_state == BBR_STATE_PROBE_BW) || 8055 (bbr->rc_bbr_state == BBR_STATE_PROBE_RTT)) { 8056 /* 8057 * If we are going back to probe-bw 8058 * or probe_rtt, we may need to possibly 8059 * do a fast restart. 8060 */ 8061 bbr_restart_after_idle(bbr, cts, idle_time); 8062 } 8063 } 8064 8065 static void 8066 bbr_collapsed_window(struct tcp_bbr *bbr) 8067 { 8068 /* 8069 * Now we must walk the 8070 * send map and divide the 8071 * ones left stranded. These 8072 * guys can't cause us to abort 8073 * the connection and are really 8074 * "unsent". However if a buggy 8075 * client actually did keep some 8076 * of the data i.e. collapsed the win 8077 * and refused to ack and then opened 8078 * the win and acked that data. We would 8079 * get into an ack war, the simplier 8080 * method then of just pretending we 8081 * did not send those segments something 8082 * won't work. 8083 */ 8084 struct bbr_sendmap *rsm, *nrsm; 8085 tcp_seq max_seq; 8086 uint32_t maxseg; 8087 int can_split = 0; 8088 int fnd = 0; 8089 8090 maxseg = bbr->rc_tp->t_maxseg - bbr->rc_last_options; 8091 max_seq = bbr->rc_tp->snd_una + bbr->rc_tp->snd_wnd; 8092 bbr_log_type_rwnd_collapse(bbr, max_seq, 1, 0); 8093 TAILQ_FOREACH(rsm, &bbr->r_ctl.rc_map, r_next) { 8094 /* Find the first seq past or at maxseq */ 8095 if (rsm->r_flags & BBR_RWND_COLLAPSED) 8096 rsm->r_flags &= ~BBR_RWND_COLLAPSED; 8097 if (SEQ_GEQ(max_seq, rsm->r_start) && 8098 SEQ_GEQ(rsm->r_end, max_seq)) { 8099 fnd = 1; 8100 break; 8101 } 8102 } 8103 bbr->rc_has_collapsed = 0; 8104 if (!fnd) { 8105 /* Nothing to do strange */ 8106 return; 8107 } 8108 /* 8109 * Now can we split? 8110 * 8111 * We don't want to split if splitting 8112 * would generate too many small segments 8113 * less we let an attacker fragment our 8114 * send_map and leave us out of memory. 8115 */ 8116 if ((max_seq != rsm->r_start) && 8117 (max_seq != rsm->r_end)){ 8118 /* can we split? */ 8119 int res1, res2; 8120 8121 res1 = max_seq - rsm->r_start; 8122 res2 = rsm->r_end - max_seq; 8123 if ((res1 >= (maxseg/8)) && 8124 (res2 >= (maxseg/8))) { 8125 /* No small pieces here */ 8126 can_split = 1; 8127 } else if (bbr->r_ctl.rc_num_small_maps_alloced < bbr_sack_block_limit) { 8128 /* We are under the limit */ 8129 can_split = 1; 8130 } 8131 } 8132 /* Ok do we need to split this rsm? */ 8133 if (max_seq == rsm->r_start) { 8134 /* It's this guy no split required */ 8135 nrsm = rsm; 8136 } else if (max_seq == rsm->r_end) { 8137 /* It's the next one no split required. */ 8138 nrsm = TAILQ_NEXT(rsm, r_next); 8139 if (nrsm == NULL) { 8140 /* Huh? */ 8141 return; 8142 } 8143 } else if (can_split && SEQ_LT(max_seq, rsm->r_end)) { 8144 /* yep we need to split it */ 8145 nrsm = bbr_alloc_limit(bbr, BBR_LIMIT_TYPE_SPLIT); 8146 if (nrsm == NULL) { 8147 /* failed XXXrrs what can we do mark the whole? */ 8148 nrsm = rsm; 8149 goto no_split; 8150 } 8151 /* Clone it */ 8152 bbr_log_type_rwnd_collapse(bbr, max_seq, 3, 0); 8153 bbr_clone_rsm(bbr, nrsm, rsm, max_seq); 8154 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_map, rsm, nrsm, r_next); 8155 if (rsm->r_in_tmap) { 8156 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, rsm, nrsm, r_tnext); 8157 nrsm->r_in_tmap = 1; 8158 } 8159 } else { 8160 /* 8161 * Split not allowed just start here just 8162 * use this guy. 8163 */ 8164 nrsm = rsm; 8165 } 8166 no_split: 8167 BBR_STAT_INC(bbr_collapsed_win); 8168 /* reuse fnd as a count */ 8169 fnd = 0; 8170 TAILQ_FOREACH_FROM(nrsm, &bbr->r_ctl.rc_map, r_next) { 8171 nrsm->r_flags |= BBR_RWND_COLLAPSED; 8172 fnd++; 8173 bbr->rc_has_collapsed = 1; 8174 } 8175 bbr_log_type_rwnd_collapse(bbr, max_seq, 4, fnd); 8176 } 8177 8178 static void 8179 bbr_un_collapse_window(struct tcp_bbr *bbr) 8180 { 8181 struct bbr_sendmap *rsm; 8182 int cleared = 0; 8183 8184 TAILQ_FOREACH_REVERSE(rsm, &bbr->r_ctl.rc_map, bbr_head, r_next) { 8185 if (rsm->r_flags & BBR_RWND_COLLAPSED) { 8186 /* Clear the flag */ 8187 rsm->r_flags &= ~BBR_RWND_COLLAPSED; 8188 cleared++; 8189 } else 8190 break; 8191 } 8192 bbr_log_type_rwnd_collapse(bbr, 8193 (bbr->rc_tp->snd_una + bbr->rc_tp->snd_wnd), 0, cleared); 8194 bbr->rc_has_collapsed = 0; 8195 } 8196 8197 /* 8198 * Return value of 1, the TCB is unlocked and most 8199 * likely gone, return value of 0, the TCB is still 8200 * locked. 8201 */ 8202 static int 8203 bbr_process_data(struct mbuf *m, struct tcphdr *th, struct socket *so, 8204 struct tcpcb *tp, int32_t drop_hdrlen, int32_t tlen, 8205 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt) 8206 { 8207 /* 8208 * Update window information. Don't look at window if no ACK: TAC's 8209 * send garbage on first SYN. 8210 */ 8211 uint16_t nsegs; 8212 int32_t tfo_syn; 8213 struct tcp_bbr *bbr; 8214 8215 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 8216 INP_WLOCK_ASSERT(tp->t_inpcb); 8217 nsegs = max(1, m->m_pkthdr.lro_nsegs); 8218 if ((thflags & TH_ACK) && 8219 (SEQ_LT(tp->snd_wl1, th->th_seq) || 8220 (tp->snd_wl1 == th->th_seq && (SEQ_LT(tp->snd_wl2, th->th_ack) || 8221 (tp->snd_wl2 == th->th_ack && tiwin > tp->snd_wnd))))) { 8222 /* keep track of pure window updates */ 8223 if (tlen == 0 && 8224 tp->snd_wl2 == th->th_ack && tiwin > tp->snd_wnd) 8225 KMOD_TCPSTAT_INC(tcps_rcvwinupd); 8226 tp->snd_wnd = tiwin; 8227 tp->snd_wl1 = th->th_seq; 8228 tp->snd_wl2 = th->th_ack; 8229 if (tp->snd_wnd > tp->max_sndwnd) 8230 tp->max_sndwnd = tp->snd_wnd; 8231 bbr->r_wanted_output = 1; 8232 } else if (thflags & TH_ACK) { 8233 if ((tp->snd_wl2 == th->th_ack) && (tiwin < tp->snd_wnd)) { 8234 tp->snd_wnd = tiwin; 8235 tp->snd_wl1 = th->th_seq; 8236 tp->snd_wl2 = th->th_ack; 8237 } 8238 } 8239 if (tp->snd_wnd < ctf_outstanding(tp)) 8240 /* The peer collapsed its window on us */ 8241 bbr_collapsed_window(bbr); 8242 else if (bbr->rc_has_collapsed) 8243 bbr_un_collapse_window(bbr); 8244 /* Was persist timer active and now we have window space? */ 8245 if ((bbr->rc_in_persist != 0) && 8246 (tp->snd_wnd >= min((bbr->r_ctl.rc_high_rwnd/2), 8247 bbr_minseg(bbr)))) { 8248 /* 8249 * Make the rate persist at end of persist mode if idle long 8250 * enough 8251 */ 8252 bbr_exit_persist(tp, bbr, bbr->r_ctl.rc_rcvtime, __LINE__); 8253 8254 /* Make sure we output to start the timer */ 8255 bbr->r_wanted_output = 1; 8256 } 8257 /* Do we need to enter persist? */ 8258 if ((bbr->rc_in_persist == 0) && 8259 (tp->snd_wnd < min((bbr->r_ctl.rc_high_rwnd/2), bbr_minseg(bbr))) && 8260 TCPS_HAVEESTABLISHED(tp->t_state) && 8261 (tp->snd_max == tp->snd_una) && 8262 sbavail(&tp->t_inpcb->inp_socket->so_snd) && 8263 (sbavail(&tp->t_inpcb->inp_socket->so_snd) > tp->snd_wnd)) { 8264 /* No send window.. we must enter persist */ 8265 bbr_enter_persist(tp, bbr, bbr->r_ctl.rc_rcvtime, __LINE__); 8266 } 8267 if (tp->t_flags2 & TF2_DROP_AF_DATA) { 8268 m_freem(m); 8269 return (0); 8270 } 8271 /* 8272 * We don't support urgent data but 8273 * drag along the up just to make sure 8274 * if there is a stack switch no one 8275 * is surprised. 8276 */ 8277 tp->rcv_up = tp->rcv_nxt; 8278 INP_WLOCK_ASSERT(tp->t_inpcb); 8279 8280 /* 8281 * Process the segment text, merging it into the TCP sequencing 8282 * queue, and arranging for acknowledgment of receipt if necessary. 8283 * This process logically involves adjusting tp->rcv_wnd as data is 8284 * presented to the user (this happens in tcp_usrreq.c, case 8285 * PRU_RCVD). If a FIN has already been received on this connection 8286 * then we just ignore the text. 8287 */ 8288 tfo_syn = ((tp->t_state == TCPS_SYN_RECEIVED) && 8289 IS_FASTOPEN(tp->t_flags)); 8290 if ((tlen || (thflags & TH_FIN) || (tfo_syn && tlen > 0)) && 8291 TCPS_HAVERCVDFIN(tp->t_state) == 0) { 8292 tcp_seq save_start = th->th_seq; 8293 tcp_seq save_rnxt = tp->rcv_nxt; 8294 int save_tlen = tlen; 8295 8296 m_adj(m, drop_hdrlen); /* delayed header drop */ 8297 /* 8298 * Insert segment which includes th into TCP reassembly 8299 * queue with control block tp. Set thflags to whether 8300 * reassembly now includes a segment with FIN. This handles 8301 * the common case inline (segment is the next to be 8302 * received on an established connection, and the queue is 8303 * empty), avoiding linkage into and removal from the queue 8304 * and repetition of various conversions. Set DELACK for 8305 * segments received in order, but ack immediately when 8306 * segments are out of order (so fast retransmit can work). 8307 */ 8308 if (th->th_seq == tp->rcv_nxt && 8309 SEGQ_EMPTY(tp) && 8310 (TCPS_HAVEESTABLISHED(tp->t_state) || 8311 tfo_syn)) { 8312 #ifdef NETFLIX_SB_LIMITS 8313 u_int mcnt, appended; 8314 8315 if (so->so_rcv.sb_shlim) { 8316 mcnt = m_memcnt(m); 8317 appended = 0; 8318 if (counter_fo_get(so->so_rcv.sb_shlim, mcnt, 8319 CFO_NOSLEEP, NULL) == false) { 8320 counter_u64_add(tcp_sb_shlim_fails, 1); 8321 m_freem(m); 8322 return (0); 8323 } 8324 } 8325 8326 #endif 8327 if (DELAY_ACK(tp, bbr, nsegs) || tfo_syn) { 8328 bbr->bbr_segs_rcvd += max(1, nsegs); 8329 tp->t_flags |= TF_DELACK; 8330 bbr_timer_cancel(bbr, __LINE__, bbr->r_ctl.rc_rcvtime); 8331 } else { 8332 bbr->r_wanted_output = 1; 8333 tp->t_flags |= TF_ACKNOW; 8334 } 8335 tp->rcv_nxt += tlen; 8336 if (tlen && 8337 ((tp->t_flags2 & TF2_FBYTES_COMPLETE) == 0) && 8338 (tp->t_fbyte_in == 0)) { 8339 tp->t_fbyte_in = ticks; 8340 if (tp->t_fbyte_in == 0) 8341 tp->t_fbyte_in = 1; 8342 if (tp->t_fbyte_out && tp->t_fbyte_in) 8343 tp->t_flags2 |= TF2_FBYTES_COMPLETE; 8344 } 8345 thflags = th->th_flags & TH_FIN; 8346 KMOD_TCPSTAT_ADD(tcps_rcvpack, (int)nsegs); 8347 KMOD_TCPSTAT_ADD(tcps_rcvbyte, tlen); 8348 SOCKBUF_LOCK(&so->so_rcv); 8349 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) 8350 m_freem(m); 8351 else 8352 #ifdef NETFLIX_SB_LIMITS 8353 appended = 8354 #endif 8355 sbappendstream_locked(&so->so_rcv, m, 0); 8356 /* NB: sorwakeup_locked() does an implicit unlock. */ 8357 sorwakeup_locked(so); 8358 #ifdef NETFLIX_SB_LIMITS 8359 if (so->so_rcv.sb_shlim && appended != mcnt) 8360 counter_fo_release(so->so_rcv.sb_shlim, 8361 mcnt - appended); 8362 #endif 8363 } else { 8364 /* 8365 * XXX: Due to the header drop above "th" is 8366 * theoretically invalid by now. Fortunately 8367 * m_adj() doesn't actually frees any mbufs when 8368 * trimming from the head. 8369 */ 8370 tcp_seq temp = save_start; 8371 thflags = tcp_reass(tp, th, &temp, &tlen, m); 8372 tp->t_flags |= TF_ACKNOW; 8373 } 8374 if ((tp->t_flags & TF_SACK_PERMIT) && (save_tlen > 0)) { 8375 if ((tlen == 0) && (SEQ_LT(save_start, save_rnxt))) { 8376 /* 8377 * DSACK actually handled in the fastpath 8378 * above. 8379 */ 8380 tcp_update_sack_list(tp, save_start, 8381 save_start + save_tlen); 8382 } else if ((tlen > 0) && SEQ_GT(tp->rcv_nxt, save_rnxt)) { 8383 if ((tp->rcv_numsacks >= 1) && 8384 (tp->sackblks[0].end == save_start)) { 8385 /* 8386 * Partial overlap, recorded at todrop 8387 * above. 8388 */ 8389 tcp_update_sack_list(tp, 8390 tp->sackblks[0].start, 8391 tp->sackblks[0].end); 8392 } else { 8393 tcp_update_dsack_list(tp, save_start, 8394 save_start + save_tlen); 8395 } 8396 } else if (tlen >= save_tlen) { 8397 /* Update of sackblks. */ 8398 tcp_update_dsack_list(tp, save_start, 8399 save_start + save_tlen); 8400 } else if (tlen > 0) { 8401 tcp_update_dsack_list(tp, save_start, 8402 save_start + tlen); 8403 } 8404 } 8405 } else { 8406 m_freem(m); 8407 thflags &= ~TH_FIN; 8408 } 8409 8410 /* 8411 * If FIN is received ACK the FIN and let the user know that the 8412 * connection is closing. 8413 */ 8414 if (thflags & TH_FIN) { 8415 if (TCPS_HAVERCVDFIN(tp->t_state) == 0) { 8416 socantrcvmore(so); 8417 /* 8418 * If connection is half-synchronized (ie NEEDSYN 8419 * flag on) then delay ACK, so it may be piggybacked 8420 * when SYN is sent. Otherwise, since we received a 8421 * FIN then no more input can be expected, send ACK 8422 * now. 8423 */ 8424 if (tp->t_flags & TF_NEEDSYN) { 8425 tp->t_flags |= TF_DELACK; 8426 bbr_timer_cancel(bbr, 8427 __LINE__, bbr->r_ctl.rc_rcvtime); 8428 } else { 8429 tp->t_flags |= TF_ACKNOW; 8430 } 8431 tp->rcv_nxt++; 8432 } 8433 switch (tp->t_state) { 8434 /* 8435 * In SYN_RECEIVED and ESTABLISHED STATES enter the 8436 * CLOSE_WAIT state. 8437 */ 8438 case TCPS_SYN_RECEIVED: 8439 tp->t_starttime = ticks; 8440 /* FALLTHROUGH */ 8441 case TCPS_ESTABLISHED: 8442 tcp_state_change(tp, TCPS_CLOSE_WAIT); 8443 break; 8444 8445 /* 8446 * If still in FIN_WAIT_1 STATE FIN has not been 8447 * acked so enter the CLOSING state. 8448 */ 8449 case TCPS_FIN_WAIT_1: 8450 tcp_state_change(tp, TCPS_CLOSING); 8451 break; 8452 8453 /* 8454 * In FIN_WAIT_2 state enter the TIME_WAIT state, 8455 * starting the time-wait timer, turning off the 8456 * other standard timers. 8457 */ 8458 case TCPS_FIN_WAIT_2: 8459 bbr->rc_timer_first = 1; 8460 bbr_timer_cancel(bbr, 8461 __LINE__, bbr->r_ctl.rc_rcvtime); 8462 INP_WLOCK_ASSERT(tp->t_inpcb); 8463 tcp_twstart(tp); 8464 return (1); 8465 } 8466 } 8467 /* 8468 * Return any desired output. 8469 */ 8470 if ((tp->t_flags & TF_ACKNOW) || 8471 (sbavail(&so->so_snd) > ctf_outstanding(tp))) { 8472 bbr->r_wanted_output = 1; 8473 } 8474 INP_WLOCK_ASSERT(tp->t_inpcb); 8475 return (0); 8476 } 8477 8478 /* 8479 * Here nothing is really faster, its just that we 8480 * have broken out the fast-data path also just like 8481 * the fast-ack. Return 1 if we processed the packet 8482 * return 0 if you need to take the "slow-path". 8483 */ 8484 static int 8485 bbr_do_fastnewdata(struct mbuf *m, struct tcphdr *th, struct socket *so, 8486 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, 8487 uint32_t tiwin, int32_t nxt_pkt) 8488 { 8489 uint16_t nsegs; 8490 int32_t newsize = 0; /* automatic sockbuf scaling */ 8491 struct tcp_bbr *bbr; 8492 #ifdef NETFLIX_SB_LIMITS 8493 u_int mcnt, appended; 8494 #endif 8495 #ifdef TCPDEBUG 8496 /* 8497 * The size of tcp_saveipgen must be the size of the max ip header, 8498 * now IPv6. 8499 */ 8500 u_char tcp_saveipgen[IP6_HDR_LEN]; 8501 struct tcphdr tcp_savetcp; 8502 short ostate = 0; 8503 8504 #endif 8505 /* On the hpts and we would have called output */ 8506 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 8507 8508 /* 8509 * If last ACK falls within this segment's sequence numbers, record 8510 * the timestamp. NOTE that the test is modified according to the 8511 * latest proposal of the tcplw@cray.com list (Braden 1993/04/26). 8512 */ 8513 if (bbr->r_ctl.rc_resend != NULL) { 8514 return (0); 8515 } 8516 if (tiwin && tiwin != tp->snd_wnd) { 8517 return (0); 8518 } 8519 if (__predict_false((tp->t_flags & (TF_NEEDSYN | TF_NEEDFIN)))) { 8520 return (0); 8521 } 8522 if (__predict_false((to->to_flags & TOF_TS) && 8523 (TSTMP_LT(to->to_tsval, tp->ts_recent)))) { 8524 return (0); 8525 } 8526 if (__predict_false((th->th_ack != tp->snd_una))) { 8527 return (0); 8528 } 8529 if (__predict_false(tlen > sbspace(&so->so_rcv))) { 8530 return (0); 8531 } 8532 if ((to->to_flags & TOF_TS) != 0 && 8533 SEQ_LEQ(th->th_seq, tp->last_ack_sent)) { 8534 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv); 8535 tp->ts_recent = to->to_tsval; 8536 } 8537 /* 8538 * This is a pure, in-sequence data packet with nothing on the 8539 * reassembly queue and we have enough buffer space to take it. 8540 */ 8541 nsegs = max(1, m->m_pkthdr.lro_nsegs); 8542 8543 #ifdef NETFLIX_SB_LIMITS 8544 if (so->so_rcv.sb_shlim) { 8545 mcnt = m_memcnt(m); 8546 appended = 0; 8547 if (counter_fo_get(so->so_rcv.sb_shlim, mcnt, 8548 CFO_NOSLEEP, NULL) == false) { 8549 counter_u64_add(tcp_sb_shlim_fails, 1); 8550 m_freem(m); 8551 return (1); 8552 } 8553 } 8554 #endif 8555 /* Clean receiver SACK report if present */ 8556 if (tp->rcv_numsacks) 8557 tcp_clean_sackreport(tp); 8558 KMOD_TCPSTAT_INC(tcps_preddat); 8559 tp->rcv_nxt += tlen; 8560 if (tlen && 8561 ((tp->t_flags2 & TF2_FBYTES_COMPLETE) == 0) && 8562 (tp->t_fbyte_in == 0)) { 8563 tp->t_fbyte_in = ticks; 8564 if (tp->t_fbyte_in == 0) 8565 tp->t_fbyte_in = 1; 8566 if (tp->t_fbyte_out && tp->t_fbyte_in) 8567 tp->t_flags2 |= TF2_FBYTES_COMPLETE; 8568 } 8569 /* 8570 * Pull snd_wl1 up to prevent seq wrap relative to th_seq. 8571 */ 8572 tp->snd_wl1 = th->th_seq; 8573 /* 8574 * Pull rcv_up up to prevent seq wrap relative to rcv_nxt. 8575 */ 8576 tp->rcv_up = tp->rcv_nxt; 8577 KMOD_TCPSTAT_ADD(tcps_rcvpack, (int)nsegs); 8578 KMOD_TCPSTAT_ADD(tcps_rcvbyte, tlen); 8579 #ifdef TCPDEBUG 8580 if (so->so_options & SO_DEBUG) 8581 tcp_trace(TA_INPUT, ostate, tp, 8582 (void *)tcp_saveipgen, &tcp_savetcp, 0); 8583 #endif 8584 newsize = tcp_autorcvbuf(m, th, so, tp, tlen); 8585 8586 /* Add data to socket buffer. */ 8587 SOCKBUF_LOCK(&so->so_rcv); 8588 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { 8589 m_freem(m); 8590 } else { 8591 /* 8592 * Set new socket buffer size. Give up when limit is 8593 * reached. 8594 */ 8595 if (newsize) 8596 if (!sbreserve_locked(&so->so_rcv, 8597 newsize, so, NULL)) 8598 so->so_rcv.sb_flags &= ~SB_AUTOSIZE; 8599 m_adj(m, drop_hdrlen); /* delayed header drop */ 8600 8601 #ifdef NETFLIX_SB_LIMITS 8602 appended = 8603 #endif 8604 sbappendstream_locked(&so->so_rcv, m, 0); 8605 ctf_calc_rwin(so, tp); 8606 } 8607 /* NB: sorwakeup_locked() does an implicit unlock. */ 8608 sorwakeup_locked(so); 8609 #ifdef NETFLIX_SB_LIMITS 8610 if (so->so_rcv.sb_shlim && mcnt != appended) 8611 counter_fo_release(so->so_rcv.sb_shlim, mcnt - appended); 8612 #endif 8613 if (DELAY_ACK(tp, bbr, nsegs)) { 8614 bbr->bbr_segs_rcvd += max(1, nsegs); 8615 tp->t_flags |= TF_DELACK; 8616 bbr_timer_cancel(bbr, __LINE__, bbr->r_ctl.rc_rcvtime); 8617 } else { 8618 bbr->r_wanted_output = 1; 8619 tp->t_flags |= TF_ACKNOW; 8620 } 8621 return (1); 8622 } 8623 8624 /* 8625 * This subfunction is used to try to highly optimize the 8626 * fast path. We again allow window updates that are 8627 * in sequence to remain in the fast-path. We also add 8628 * in the __predict's to attempt to help the compiler. 8629 * Note that if we return a 0, then we can *not* process 8630 * it and the caller should push the packet into the 8631 * slow-path. If we return 1, then all is well and 8632 * the packet is fully processed. 8633 */ 8634 static int 8635 bbr_fastack(struct mbuf *m, struct tcphdr *th, struct socket *so, 8636 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, 8637 uint32_t tiwin, int32_t nxt_pkt, uint8_t iptos) 8638 { 8639 int32_t acked; 8640 uint16_t nsegs; 8641 uint32_t sack_changed; 8642 #ifdef TCPDEBUG 8643 /* 8644 * The size of tcp_saveipgen must be the size of the max ip header, 8645 * now IPv6. 8646 */ 8647 u_char tcp_saveipgen[IP6_HDR_LEN]; 8648 struct tcphdr tcp_savetcp; 8649 short ostate = 0; 8650 8651 #endif 8652 uint32_t prev_acked = 0; 8653 struct tcp_bbr *bbr; 8654 8655 if (__predict_false(SEQ_LEQ(th->th_ack, tp->snd_una))) { 8656 /* Old ack, behind (or duplicate to) the last one rcv'd */ 8657 return (0); 8658 } 8659 if (__predict_false(SEQ_GT(th->th_ack, tp->snd_max))) { 8660 /* Above what we have sent? */ 8661 return (0); 8662 } 8663 if (__predict_false(tiwin == 0)) { 8664 /* zero window */ 8665 return (0); 8666 } 8667 if (__predict_false(tp->t_flags & (TF_NEEDSYN | TF_NEEDFIN))) { 8668 /* We need a SYN or a FIN, unlikely.. */ 8669 return (0); 8670 } 8671 if ((to->to_flags & TOF_TS) && __predict_false(TSTMP_LT(to->to_tsval, tp->ts_recent))) { 8672 /* Timestamp is behind .. old ack with seq wrap? */ 8673 return (0); 8674 } 8675 if (__predict_false(IN_RECOVERY(tp->t_flags))) { 8676 /* Still recovering */ 8677 return (0); 8678 } 8679 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 8680 if (__predict_false(bbr->r_ctl.rc_resend != NULL)) { 8681 /* We are retransmitting */ 8682 return (0); 8683 } 8684 if (__predict_false(bbr->rc_in_persist != 0)) { 8685 /* In persist mode */ 8686 return (0); 8687 } 8688 if (bbr->r_ctl.rc_sacked) { 8689 /* We have sack holes on our scoreboard */ 8690 return (0); 8691 } 8692 /* Ok if we reach here, we can process a fast-ack */ 8693 nsegs = max(1, m->m_pkthdr.lro_nsegs); 8694 sack_changed = bbr_log_ack(tp, to, th, &prev_acked); 8695 /* 8696 * We never detect loss in fast ack [we can't 8697 * have a sack and can't be in recovery so 8698 * we always pass 0 (nothing detected)]. 8699 */ 8700 bbr_lt_bw_sampling(bbr, bbr->r_ctl.rc_rcvtime, 0); 8701 /* Did the window get updated? */ 8702 if (tiwin != tp->snd_wnd) { 8703 tp->snd_wnd = tiwin; 8704 tp->snd_wl1 = th->th_seq; 8705 if (tp->snd_wnd > tp->max_sndwnd) 8706 tp->max_sndwnd = tp->snd_wnd; 8707 } 8708 /* Do we need to exit persists? */ 8709 if ((bbr->rc_in_persist != 0) && 8710 (tp->snd_wnd >= min((bbr->r_ctl.rc_high_rwnd/2), 8711 bbr_minseg(bbr)))) { 8712 bbr_exit_persist(tp, bbr, bbr->r_ctl.rc_rcvtime, __LINE__); 8713 bbr->r_wanted_output = 1; 8714 } 8715 /* Do we need to enter persists? */ 8716 if ((bbr->rc_in_persist == 0) && 8717 (tp->snd_wnd < min((bbr->r_ctl.rc_high_rwnd/2), bbr_minseg(bbr))) && 8718 TCPS_HAVEESTABLISHED(tp->t_state) && 8719 (tp->snd_max == tp->snd_una) && 8720 sbavail(&tp->t_inpcb->inp_socket->so_snd) && 8721 (sbavail(&tp->t_inpcb->inp_socket->so_snd) > tp->snd_wnd)) { 8722 /* No send window.. we must enter persist */ 8723 bbr_enter_persist(tp, bbr, bbr->r_ctl.rc_rcvtime, __LINE__); 8724 } 8725 /* 8726 * If last ACK falls within this segment's sequence numbers, record 8727 * the timestamp. NOTE that the test is modified according to the 8728 * latest proposal of the tcplw@cray.com list (Braden 1993/04/26). 8729 */ 8730 if ((to->to_flags & TOF_TS) != 0 && 8731 SEQ_LEQ(th->th_seq, tp->last_ack_sent)) { 8732 tp->ts_recent_age = bbr->r_ctl.rc_rcvtime; 8733 tp->ts_recent = to->to_tsval; 8734 } 8735 /* 8736 * This is a pure ack for outstanding data. 8737 */ 8738 KMOD_TCPSTAT_INC(tcps_predack); 8739 8740 /* 8741 * "bad retransmit" recovery. 8742 */ 8743 if (tp->t_flags & TF_PREVVALID) { 8744 tp->t_flags &= ~TF_PREVVALID; 8745 if (tp->t_rxtshift == 1 && 8746 (int)(ticks - tp->t_badrxtwin) < 0) 8747 bbr_cong_signal(tp, th, CC_RTO_ERR, NULL); 8748 } 8749 /* 8750 * Recalculate the transmit timer / rtt. 8751 * 8752 * Some boxes send broken timestamp replies during the SYN+ACK 8753 * phase, ignore timestamps of 0 or we could calculate a huge RTT 8754 * and blow up the retransmit timer. 8755 */ 8756 acked = BYTES_THIS_ACK(tp, th); 8757 8758 #ifdef TCP_HHOOK 8759 /* Run HHOOK_TCP_ESTABLISHED_IN helper hooks. */ 8760 hhook_run_tcp_est_in(tp, th, to); 8761 #endif 8762 8763 KMOD_TCPSTAT_ADD(tcps_rcvackpack, (int)nsegs); 8764 KMOD_TCPSTAT_ADD(tcps_rcvackbyte, acked); 8765 sbdrop(&so->so_snd, acked); 8766 8767 if (SEQ_GT(th->th_ack, tp->snd_una)) 8768 bbr_collapse_rtt(tp, bbr, TCP_REXMTVAL(tp)); 8769 tp->snd_una = th->th_ack; 8770 if (tp->snd_wnd < ctf_outstanding(tp)) 8771 /* The peer collapsed its window on us */ 8772 bbr_collapsed_window(bbr); 8773 else if (bbr->rc_has_collapsed) 8774 bbr_un_collapse_window(bbr); 8775 8776 if (SEQ_GT(tp->snd_una, tp->snd_recover)) { 8777 tp->snd_recover = tp->snd_una; 8778 } 8779 bbr_ack_received(tp, bbr, th, acked, sack_changed, prev_acked, __LINE__, 0); 8780 /* 8781 * Pull snd_wl2 up to prevent seq wrap relative to th_ack. 8782 */ 8783 tp->snd_wl2 = th->th_ack; 8784 m_freem(m); 8785 /* 8786 * If all outstanding data are acked, stop retransmit timer, 8787 * otherwise restart timer using current (possibly backed-off) 8788 * value. If process is waiting for space, wakeup/selwakeup/signal. 8789 * If data are ready to send, let tcp_output decide between more 8790 * output or persist. 8791 */ 8792 #ifdef TCPDEBUG 8793 if (so->so_options & SO_DEBUG) 8794 tcp_trace(TA_INPUT, ostate, tp, 8795 (void *)tcp_saveipgen, 8796 &tcp_savetcp, 0); 8797 #endif 8798 /* Wake up the socket if we have room to write more */ 8799 sowwakeup(so); 8800 if (tp->snd_una == tp->snd_max) { 8801 /* Nothing left outstanding */ 8802 bbr_log_progress_event(bbr, tp, ticks, PROGRESS_CLEAR, __LINE__); 8803 if (sbavail(&tp->t_inpcb->inp_socket->so_snd) == 0) 8804 bbr->rc_tp->t_acktime = 0; 8805 bbr_timer_cancel(bbr, __LINE__, bbr->r_ctl.rc_rcvtime); 8806 if (bbr->rc_in_persist == 0) { 8807 bbr->r_ctl.rc_went_idle_time = bbr->r_ctl.rc_rcvtime; 8808 } 8809 sack_filter_clear(&bbr->r_ctl.bbr_sf, tp->snd_una); 8810 bbr_log_ack_clear(bbr, bbr->r_ctl.rc_rcvtime); 8811 /* 8812 * We invalidate the last ack here since we 8813 * don't want to transfer forward the time 8814 * for our sum's calculations. 8815 */ 8816 bbr->r_wanted_output = 1; 8817 } 8818 if (sbavail(&so->so_snd)) { 8819 bbr->r_wanted_output = 1; 8820 } 8821 return (1); 8822 } 8823 8824 /* 8825 * Return value of 1, the TCB is unlocked and most 8826 * likely gone, return value of 0, the TCB is still 8827 * locked. 8828 */ 8829 static int 8830 bbr_do_syn_sent(struct mbuf *m, struct tcphdr *th, struct socket *so, 8831 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, 8832 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos) 8833 { 8834 int32_t todrop; 8835 int32_t ourfinisacked = 0; 8836 struct tcp_bbr *bbr; 8837 int32_t ret_val = 0; 8838 8839 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 8840 ctf_calc_rwin(so, tp); 8841 /* 8842 * If the state is SYN_SENT: if seg contains an ACK, but not for our 8843 * SYN, drop the input. if seg contains a RST, then drop the 8844 * connection. if seg does not contain SYN, then drop it. Otherwise 8845 * this is an acceptable SYN segment initialize tp->rcv_nxt and 8846 * tp->irs if seg contains ack then advance tp->snd_una. BRR does 8847 * not support ECN so we will not say we are capable. if SYN has 8848 * been acked change to ESTABLISHED else SYN_RCVD state arrange for 8849 * segment to be acked (eventually) continue processing rest of 8850 * data/controls, beginning with URG 8851 */ 8852 if ((thflags & TH_ACK) && 8853 (SEQ_LEQ(th->th_ack, tp->iss) || 8854 SEQ_GT(th->th_ack, tp->snd_max))) { 8855 tcp_log_end_status(tp, TCP_EI_STATUS_RST_IN_FRONT); 8856 ctf_do_dropwithreset(m, tp, th, BANDLIM_RST_OPENPORT, tlen); 8857 return (1); 8858 } 8859 if ((thflags & (TH_ACK | TH_RST)) == (TH_ACK | TH_RST)) { 8860 TCP_PROBE5(connect__refused, NULL, tp, 8861 mtod(m, const char *), tp, th); 8862 tp = tcp_drop(tp, ECONNREFUSED); 8863 ctf_do_drop(m, tp); 8864 return (1); 8865 } 8866 if (thflags & TH_RST) { 8867 ctf_do_drop(m, tp); 8868 return (1); 8869 } 8870 if (!(thflags & TH_SYN)) { 8871 ctf_do_drop(m, tp); 8872 return (1); 8873 } 8874 tp->irs = th->th_seq; 8875 tcp_rcvseqinit(tp); 8876 if (thflags & TH_ACK) { 8877 int tfo_partial = 0; 8878 8879 KMOD_TCPSTAT_INC(tcps_connects); 8880 soisconnected(so); 8881 #ifdef MAC 8882 mac_socketpeer_set_from_mbuf(m, so); 8883 #endif 8884 /* Do window scaling on this connection? */ 8885 if ((tp->t_flags & (TF_RCVD_SCALE | TF_REQ_SCALE)) == 8886 (TF_RCVD_SCALE | TF_REQ_SCALE)) { 8887 tp->rcv_scale = tp->request_r_scale; 8888 } 8889 tp->rcv_adv += min(tp->rcv_wnd, 8890 TCP_MAXWIN << tp->rcv_scale); 8891 /* 8892 * If not all the data that was sent in the TFO SYN 8893 * has been acked, resend the remainder right away. 8894 */ 8895 if (IS_FASTOPEN(tp->t_flags) && 8896 (tp->snd_una != tp->snd_max)) { 8897 tp->snd_nxt = th->th_ack; 8898 tfo_partial = 1; 8899 } 8900 /* 8901 * If there's data, delay ACK; if there's also a FIN ACKNOW 8902 * will be turned on later. 8903 */ 8904 if (DELAY_ACK(tp, bbr, 1) && tlen != 0 && !tfo_partial) { 8905 bbr->bbr_segs_rcvd += 1; 8906 tp->t_flags |= TF_DELACK; 8907 bbr_timer_cancel(bbr, __LINE__, bbr->r_ctl.rc_rcvtime); 8908 } else { 8909 bbr->r_wanted_output = 1; 8910 tp->t_flags |= TF_ACKNOW; 8911 } 8912 if (SEQ_GT(th->th_ack, tp->iss)) { 8913 /* 8914 * The SYN is acked 8915 * handle it specially. 8916 */ 8917 bbr_log_syn(tp, to); 8918 } 8919 if (SEQ_GT(th->th_ack, tp->snd_una)) { 8920 /* 8921 * We advance snd_una for the 8922 * fast open case. If th_ack is 8923 * acknowledging data beyond 8924 * snd_una we can't just call 8925 * ack-processing since the 8926 * data stream in our send-map 8927 * will start at snd_una + 1 (one 8928 * beyond the SYN). If its just 8929 * equal we don't need to do that 8930 * and there is no send_map. 8931 */ 8932 tp->snd_una++; 8933 } 8934 /* 8935 * Received <SYN,ACK> in SYN_SENT[*] state. Transitions: 8936 * SYN_SENT --> ESTABLISHED SYN_SENT* --> FIN_WAIT_1 8937 */ 8938 tp->t_starttime = ticks; 8939 if (tp->t_flags & TF_NEEDFIN) { 8940 tcp_state_change(tp, TCPS_FIN_WAIT_1); 8941 tp->t_flags &= ~TF_NEEDFIN; 8942 thflags &= ~TH_SYN; 8943 } else { 8944 tcp_state_change(tp, TCPS_ESTABLISHED); 8945 TCP_PROBE5(connect__established, NULL, tp, 8946 mtod(m, const char *), tp, th); 8947 cc_conn_init(tp); 8948 } 8949 } else { 8950 /* 8951 * Received initial SYN in SYN-SENT[*] state => simultaneous 8952 * open. If segment contains CC option and there is a 8953 * cached CC, apply TAO test. If it succeeds, connection is * 8954 * half-synchronized. Otherwise, do 3-way handshake: 8955 * SYN-SENT -> SYN-RECEIVED SYN-SENT* -> SYN-RECEIVED* If 8956 * there was no CC option, clear cached CC value. 8957 */ 8958 tp->t_flags |= (TF_ACKNOW | TF_NEEDSYN); 8959 tcp_state_change(tp, TCPS_SYN_RECEIVED); 8960 } 8961 INP_WLOCK_ASSERT(tp->t_inpcb); 8962 /* 8963 * Advance th->th_seq to correspond to first data byte. If data, 8964 * trim to stay within window, dropping FIN if necessary. 8965 */ 8966 th->th_seq++; 8967 if (tlen > tp->rcv_wnd) { 8968 todrop = tlen - tp->rcv_wnd; 8969 m_adj(m, -todrop); 8970 tlen = tp->rcv_wnd; 8971 thflags &= ~TH_FIN; 8972 KMOD_TCPSTAT_INC(tcps_rcvpackafterwin); 8973 KMOD_TCPSTAT_ADD(tcps_rcvbyteafterwin, todrop); 8974 } 8975 tp->snd_wl1 = th->th_seq - 1; 8976 tp->rcv_up = th->th_seq; 8977 /* 8978 * Client side of transaction: already sent SYN and data. If the 8979 * remote host used T/TCP to validate the SYN, our data will be 8980 * ACK'd; if so, enter normal data segment processing in the middle 8981 * of step 5, ack processing. Otherwise, goto step 6. 8982 */ 8983 if (thflags & TH_ACK) { 8984 if ((to->to_flags & TOF_TS) != 0) { 8985 uint32_t t, rtt; 8986 8987 t = tcp_tv_to_mssectick(&bbr->rc_tv); 8988 if (TSTMP_GEQ(t, to->to_tsecr)) { 8989 rtt = t - to->to_tsecr; 8990 if (rtt == 0) { 8991 rtt = 1; 8992 } 8993 rtt *= MS_IN_USEC; 8994 tcp_bbr_xmit_timer(bbr, rtt, 0, 0, 0); 8995 apply_filter_min_small(&bbr->r_ctl.rc_rttprop, 8996 rtt, bbr->r_ctl.rc_rcvtime); 8997 } 8998 } 8999 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val)) 9000 return (ret_val); 9001 /* We may have changed to FIN_WAIT_1 above */ 9002 if (tp->t_state == TCPS_FIN_WAIT_1) { 9003 /* 9004 * In FIN_WAIT_1 STATE in addition to the processing 9005 * for the ESTABLISHED state if our FIN is now 9006 * acknowledged then enter FIN_WAIT_2. 9007 */ 9008 if (ourfinisacked) { 9009 /* 9010 * If we can't receive any more data, then 9011 * closing user can proceed. Starting the 9012 * timer is contrary to the specification, 9013 * but if we don't get a FIN we'll hang 9014 * forever. 9015 * 9016 * XXXjl: we should release the tp also, and 9017 * use a compressed state. 9018 */ 9019 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { 9020 soisdisconnected(so); 9021 tcp_timer_activate(tp, TT_2MSL, 9022 (tcp_fast_finwait2_recycle ? 9023 tcp_finwait2_timeout : 9024 TP_MAXIDLE(tp))); 9025 } 9026 tcp_state_change(tp, TCPS_FIN_WAIT_2); 9027 } 9028 } 9029 } 9030 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9031 tiwin, thflags, nxt_pkt)); 9032 } 9033 9034 /* 9035 * Return value of 1, the TCB is unlocked and most 9036 * likely gone, return value of 0, the TCB is still 9037 * locked. 9038 */ 9039 static int 9040 bbr_do_syn_recv(struct mbuf *m, struct tcphdr *th, struct socket *so, 9041 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, 9042 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos) 9043 { 9044 int32_t ourfinisacked = 0; 9045 int32_t ret_val; 9046 struct tcp_bbr *bbr; 9047 9048 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 9049 ctf_calc_rwin(so, tp); 9050 if ((thflags & TH_ACK) && 9051 (SEQ_LEQ(th->th_ack, tp->snd_una) || 9052 SEQ_GT(th->th_ack, tp->snd_max))) { 9053 tcp_log_end_status(tp, TCP_EI_STATUS_RST_IN_FRONT); 9054 ctf_do_dropwithreset(m, tp, th, BANDLIM_RST_OPENPORT, tlen); 9055 return (1); 9056 } 9057 if (IS_FASTOPEN(tp->t_flags)) { 9058 /* 9059 * When a TFO connection is in SYN_RECEIVED, the only valid 9060 * packets are the initial SYN, a retransmit/copy of the 9061 * initial SYN (possibly with a subset of the original 9062 * data), a valid ACK, a FIN, or a RST. 9063 */ 9064 if ((thflags & (TH_SYN | TH_ACK)) == (TH_SYN | TH_ACK)) { 9065 tcp_log_end_status(tp, TCP_EI_STATUS_RST_IN_FRONT); 9066 ctf_do_dropwithreset(m, tp, th, BANDLIM_RST_OPENPORT, tlen); 9067 return (1); 9068 } else if (thflags & TH_SYN) { 9069 /* non-initial SYN is ignored */ 9070 if ((bbr->r_ctl.rc_hpts_flags & PACE_TMR_RXT) || 9071 (bbr->r_ctl.rc_hpts_flags & PACE_TMR_TLP) || 9072 (bbr->r_ctl.rc_hpts_flags & PACE_TMR_RACK)) { 9073 ctf_do_drop(m, NULL); 9074 return (0); 9075 } 9076 } else if (!(thflags & (TH_ACK | TH_FIN | TH_RST))) { 9077 ctf_do_drop(m, NULL); 9078 return (0); 9079 } 9080 } 9081 if ((thflags & TH_RST) || 9082 (tp->t_fin_is_rst && (thflags & TH_FIN))) 9083 return (ctf_process_rst(m, th, so, tp)); 9084 /* 9085 * RFC 1323 PAWS: If we have a timestamp reply on this segment and 9086 * it's less than ts_recent, drop it. 9087 */ 9088 if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent && 9089 TSTMP_LT(to->to_tsval, tp->ts_recent)) { 9090 if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val)) 9091 return (ret_val); 9092 } 9093 /* 9094 * In the SYN-RECEIVED state, validate that the packet belongs to 9095 * this connection before trimming the data to fit the receive 9096 * window. Check the sequence number versus IRS since we know the 9097 * sequence numbers haven't wrapped. This is a partial fix for the 9098 * "LAND" DoS attack. 9099 */ 9100 if (SEQ_LT(th->th_seq, tp->irs)) { 9101 tcp_log_end_status(tp, TCP_EI_STATUS_RST_IN_FRONT); 9102 ctf_do_dropwithreset(m, tp, th, BANDLIM_RST_OPENPORT, tlen); 9103 return (1); 9104 } 9105 INP_WLOCK_ASSERT(tp->t_inpcb); 9106 if (ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val)) { 9107 return (ret_val); 9108 } 9109 /* 9110 * If last ACK falls within this segment's sequence numbers, record 9111 * its timestamp. NOTE: 1) That the test incorporates suggestions 9112 * from the latest proposal of the tcplw@cray.com list (Braden 9113 * 1993/04/26). 2) That updating only on newer timestamps interferes 9114 * with our earlier PAWS tests, so this check should be solely 9115 * predicated on the sequence space of this segment. 3) That we 9116 * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ 9117 * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ + 9118 * SEG.Len, This modified check allows us to overcome RFC1323's 9119 * limitations as described in Stevens TCP/IP Illustrated Vol. 2 9120 * p.869. In such cases, we can still calculate the RTT correctly 9121 * when RCV.NXT == Last.ACK.Sent. 9122 */ 9123 if ((to->to_flags & TOF_TS) != 0 && 9124 SEQ_LEQ(th->th_seq, tp->last_ack_sent) && 9125 SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen + 9126 ((thflags & (TH_SYN | TH_FIN)) != 0))) { 9127 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv); 9128 tp->ts_recent = to->to_tsval; 9129 } 9130 tp->snd_wnd = tiwin; 9131 /* 9132 * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag 9133 * is on (half-synchronized state), then queue data for later 9134 * processing; else drop segment and return. 9135 */ 9136 if ((thflags & TH_ACK) == 0) { 9137 if (IS_FASTOPEN(tp->t_flags)) { 9138 cc_conn_init(tp); 9139 } 9140 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9141 tiwin, thflags, nxt_pkt)); 9142 } 9143 KMOD_TCPSTAT_INC(tcps_connects); 9144 soisconnected(so); 9145 /* Do window scaling? */ 9146 if ((tp->t_flags & (TF_RCVD_SCALE | TF_REQ_SCALE)) == 9147 (TF_RCVD_SCALE | TF_REQ_SCALE)) { 9148 tp->rcv_scale = tp->request_r_scale; 9149 } 9150 /* 9151 * ok for the first time in lets see if we can use the ts to figure 9152 * out what the initial RTT was. 9153 */ 9154 if ((to->to_flags & TOF_TS) != 0) { 9155 uint32_t t, rtt; 9156 9157 t = tcp_tv_to_mssectick(&bbr->rc_tv); 9158 if (TSTMP_GEQ(t, to->to_tsecr)) { 9159 rtt = t - to->to_tsecr; 9160 if (rtt == 0) { 9161 rtt = 1; 9162 } 9163 rtt *= MS_IN_USEC; 9164 tcp_bbr_xmit_timer(bbr, rtt, 0, 0, 0); 9165 apply_filter_min_small(&bbr->r_ctl.rc_rttprop, rtt, bbr->r_ctl.rc_rcvtime); 9166 } 9167 } 9168 /* Drop off any SYN in the send map (probably not there) */ 9169 if (thflags & TH_ACK) 9170 bbr_log_syn(tp, to); 9171 if (IS_FASTOPEN(tp->t_flags) && tp->t_tfo_pending) { 9172 tcp_fastopen_decrement_counter(tp->t_tfo_pending); 9173 tp->t_tfo_pending = NULL; 9174 } 9175 /* 9176 * Make transitions: SYN-RECEIVED -> ESTABLISHED SYN-RECEIVED* -> 9177 * FIN-WAIT-1 9178 */ 9179 tp->t_starttime = ticks; 9180 if (tp->t_flags & TF_NEEDFIN) { 9181 tcp_state_change(tp, TCPS_FIN_WAIT_1); 9182 tp->t_flags &= ~TF_NEEDFIN; 9183 } else { 9184 tcp_state_change(tp, TCPS_ESTABLISHED); 9185 TCP_PROBE5(accept__established, NULL, tp, 9186 mtod(m, const char *), tp, th); 9187 /* 9188 * TFO connections call cc_conn_init() during SYN 9189 * processing. Calling it again here for such connections 9190 * is not harmless as it would undo the snd_cwnd reduction 9191 * that occurs when a TFO SYN|ACK is retransmitted. 9192 */ 9193 if (!IS_FASTOPEN(tp->t_flags)) 9194 cc_conn_init(tp); 9195 } 9196 /* 9197 * Account for the ACK of our SYN prior to 9198 * regular ACK processing below, except for 9199 * simultaneous SYN, which is handled later. 9200 */ 9201 if (SEQ_GT(th->th_ack, tp->snd_una) && !(tp->t_flags & TF_NEEDSYN)) 9202 tp->snd_una++; 9203 /* 9204 * If segment contains data or ACK, will call tcp_reass() later; if 9205 * not, do so now to pass queued data to user. 9206 */ 9207 if (tlen == 0 && (thflags & TH_FIN) == 0) 9208 (void)tcp_reass(tp, (struct tcphdr *)0, NULL, 0, 9209 (struct mbuf *)0); 9210 tp->snd_wl1 = th->th_seq - 1; 9211 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val)) { 9212 return (ret_val); 9213 } 9214 if (tp->t_state == TCPS_FIN_WAIT_1) { 9215 /* We could have went to FIN_WAIT_1 (or EST) above */ 9216 /* 9217 * In FIN_WAIT_1 STATE in addition to the processing for the 9218 * ESTABLISHED state if our FIN is now acknowledged then 9219 * enter FIN_WAIT_2. 9220 */ 9221 if (ourfinisacked) { 9222 /* 9223 * If we can't receive any more data, then closing 9224 * user can proceed. Starting the timer is contrary 9225 * to the specification, but if we don't get a FIN 9226 * we'll hang forever. 9227 * 9228 * XXXjl: we should release the tp also, and use a 9229 * compressed state. 9230 */ 9231 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { 9232 soisdisconnected(so); 9233 tcp_timer_activate(tp, TT_2MSL, 9234 (tcp_fast_finwait2_recycle ? 9235 tcp_finwait2_timeout : 9236 TP_MAXIDLE(tp))); 9237 } 9238 tcp_state_change(tp, TCPS_FIN_WAIT_2); 9239 } 9240 } 9241 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9242 tiwin, thflags, nxt_pkt)); 9243 } 9244 9245 /* 9246 * Return value of 1, the TCB is unlocked and most 9247 * likely gone, return value of 0, the TCB is still 9248 * locked. 9249 */ 9250 static int 9251 bbr_do_established(struct mbuf *m, struct tcphdr *th, struct socket *so, 9252 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, 9253 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos) 9254 { 9255 struct tcp_bbr *bbr; 9256 int32_t ret_val; 9257 9258 /* 9259 * Header prediction: check for the two common cases of a 9260 * uni-directional data xfer. If the packet has no control flags, 9261 * is in-sequence, the window didn't change and we're not 9262 * retransmitting, it's a candidate. If the length is zero and the 9263 * ack moved forward, we're the sender side of the xfer. Just free 9264 * the data acked & wake any higher level process that was blocked 9265 * waiting for space. If the length is non-zero and the ack didn't 9266 * move, we're the receiver side. If we're getting packets in-order 9267 * (the reassembly queue is empty), add the data toc The socket 9268 * buffer and note that we need a delayed ack. Make sure that the 9269 * hidden state-flags are also off. Since we check for 9270 * TCPS_ESTABLISHED first, it can only be TH_NEEDSYN. 9271 */ 9272 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 9273 if (bbr->r_ctl.rc_delivered < (4 * tp->t_maxseg)) { 9274 /* 9275 * If we have delived under 4 segments increase the initial 9276 * window if raised by the peer. We use this to determine 9277 * dynamic and static rwnd's at the end of a connection. 9278 */ 9279 bbr->r_ctl.rc_init_rwnd = max(tiwin, tp->snd_wnd); 9280 } 9281 if (__predict_true(((to->to_flags & TOF_SACK) == 0)) && 9282 __predict_true((thflags & (TH_SYN | TH_FIN | TH_RST | TH_URG | TH_ACK)) == TH_ACK) && 9283 __predict_true(SEGQ_EMPTY(tp)) && 9284 __predict_true(th->th_seq == tp->rcv_nxt)) { 9285 if (tlen == 0) { 9286 if (bbr_fastack(m, th, so, tp, to, drop_hdrlen, tlen, 9287 tiwin, nxt_pkt, iptos)) { 9288 return (0); 9289 } 9290 } else { 9291 if (bbr_do_fastnewdata(m, th, so, tp, to, drop_hdrlen, tlen, 9292 tiwin, nxt_pkt)) { 9293 return (0); 9294 } 9295 } 9296 } 9297 ctf_calc_rwin(so, tp); 9298 9299 if ((thflags & TH_RST) || 9300 (tp->t_fin_is_rst && (thflags & TH_FIN))) 9301 return (ctf_process_rst(m, th, so, tp)); 9302 /* 9303 * RFC5961 Section 4.2 Send challenge ACK for any SYN in 9304 * synchronized state. 9305 */ 9306 if (thflags & TH_SYN) { 9307 ctf_challenge_ack(m, th, tp, &ret_val); 9308 return (ret_val); 9309 } 9310 /* 9311 * RFC 1323 PAWS: If we have a timestamp reply on this segment and 9312 * it's less than ts_recent, drop it. 9313 */ 9314 if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent && 9315 TSTMP_LT(to->to_tsval, tp->ts_recent)) { 9316 if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val)) 9317 return (ret_val); 9318 } 9319 INP_WLOCK_ASSERT(tp->t_inpcb); 9320 if (ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val)) { 9321 return (ret_val); 9322 } 9323 /* 9324 * If last ACK falls within this segment's sequence numbers, record 9325 * its timestamp. NOTE: 1) That the test incorporates suggestions 9326 * from the latest proposal of the tcplw@cray.com list (Braden 9327 * 1993/04/26). 2) That updating only on newer timestamps interferes 9328 * with our earlier PAWS tests, so this check should be solely 9329 * predicated on the sequence space of this segment. 3) That we 9330 * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ 9331 * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ + 9332 * SEG.Len, This modified check allows us to overcome RFC1323's 9333 * limitations as described in Stevens TCP/IP Illustrated Vol. 2 9334 * p.869. In such cases, we can still calculate the RTT correctly 9335 * when RCV.NXT == Last.ACK.Sent. 9336 */ 9337 if ((to->to_flags & TOF_TS) != 0 && 9338 SEQ_LEQ(th->th_seq, tp->last_ack_sent) && 9339 SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen + 9340 ((thflags & (TH_SYN | TH_FIN)) != 0))) { 9341 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv); 9342 tp->ts_recent = to->to_tsval; 9343 } 9344 /* 9345 * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag 9346 * is on (half-synchronized state), then queue data for later 9347 * processing; else drop segment and return. 9348 */ 9349 if ((thflags & TH_ACK) == 0) { 9350 if (tp->t_flags & TF_NEEDSYN) { 9351 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9352 tiwin, thflags, nxt_pkt)); 9353 } else if (tp->t_flags & TF_ACKNOW) { 9354 ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val); 9355 bbr->r_wanted_output = 1; 9356 return (ret_val); 9357 } else { 9358 ctf_do_drop(m, NULL); 9359 return (0); 9360 } 9361 } 9362 /* 9363 * Ack processing. 9364 */ 9365 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, NULL, thflags, &ret_val)) { 9366 return (ret_val); 9367 } 9368 if (sbavail(&so->so_snd)) { 9369 if (ctf_progress_timeout_check(tp, true)) { 9370 bbr_log_progress_event(bbr, tp, tick, PROGRESS_DROP, __LINE__); 9371 ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen); 9372 return (1); 9373 } 9374 } 9375 /* State changes only happen in bbr_process_data() */ 9376 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9377 tiwin, thflags, nxt_pkt)); 9378 } 9379 9380 /* 9381 * Return value of 1, the TCB is unlocked and most 9382 * likely gone, return value of 0, the TCB is still 9383 * locked. 9384 */ 9385 static int 9386 bbr_do_close_wait(struct mbuf *m, struct tcphdr *th, struct socket *so, 9387 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, 9388 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos) 9389 { 9390 struct tcp_bbr *bbr; 9391 int32_t ret_val; 9392 9393 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 9394 ctf_calc_rwin(so, tp); 9395 if ((thflags & TH_RST) || 9396 (tp->t_fin_is_rst && (thflags & TH_FIN))) 9397 return (ctf_process_rst(m, th, so, tp)); 9398 /* 9399 * RFC5961 Section 4.2 Send challenge ACK for any SYN in 9400 * synchronized state. 9401 */ 9402 if (thflags & TH_SYN) { 9403 ctf_challenge_ack(m, th, tp, &ret_val); 9404 return (ret_val); 9405 } 9406 /* 9407 * RFC 1323 PAWS: If we have a timestamp reply on this segment and 9408 * it's less than ts_recent, drop it. 9409 */ 9410 if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent && 9411 TSTMP_LT(to->to_tsval, tp->ts_recent)) { 9412 if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val)) 9413 return (ret_val); 9414 } 9415 INP_WLOCK_ASSERT(tp->t_inpcb); 9416 if (ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val)) { 9417 return (ret_val); 9418 } 9419 /* 9420 * If last ACK falls within this segment's sequence numbers, record 9421 * its timestamp. NOTE: 1) That the test incorporates suggestions 9422 * from the latest proposal of the tcplw@cray.com list (Braden 9423 * 1993/04/26). 2) That updating only on newer timestamps interferes 9424 * with our earlier PAWS tests, so this check should be solely 9425 * predicated on the sequence space of this segment. 3) That we 9426 * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ 9427 * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ + 9428 * SEG.Len, This modified check allows us to overcome RFC1323's 9429 * limitations as described in Stevens TCP/IP Illustrated Vol. 2 9430 * p.869. In such cases, we can still calculate the RTT correctly 9431 * when RCV.NXT == Last.ACK.Sent. 9432 */ 9433 if ((to->to_flags & TOF_TS) != 0 && 9434 SEQ_LEQ(th->th_seq, tp->last_ack_sent) && 9435 SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen + 9436 ((thflags & (TH_SYN | TH_FIN)) != 0))) { 9437 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv); 9438 tp->ts_recent = to->to_tsval; 9439 } 9440 /* 9441 * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag 9442 * is on (half-synchronized state), then queue data for later 9443 * processing; else drop segment and return. 9444 */ 9445 if ((thflags & TH_ACK) == 0) { 9446 if (tp->t_flags & TF_NEEDSYN) { 9447 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9448 tiwin, thflags, nxt_pkt)); 9449 } else if (tp->t_flags & TF_ACKNOW) { 9450 ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val); 9451 bbr->r_wanted_output = 1; 9452 return (ret_val); 9453 } else { 9454 ctf_do_drop(m, NULL); 9455 return (0); 9456 } 9457 } 9458 /* 9459 * Ack processing. 9460 */ 9461 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, NULL, thflags, &ret_val)) { 9462 return (ret_val); 9463 } 9464 if (sbavail(&so->so_snd)) { 9465 if (ctf_progress_timeout_check(tp, true)) { 9466 bbr_log_progress_event(bbr, tp, tick, PROGRESS_DROP, __LINE__); 9467 ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen); 9468 return (1); 9469 } 9470 } 9471 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9472 tiwin, thflags, nxt_pkt)); 9473 } 9474 9475 static int 9476 bbr_check_data_after_close(struct mbuf *m, struct tcp_bbr *bbr, 9477 struct tcpcb *tp, int32_t * tlen, struct tcphdr *th, struct socket *so) 9478 { 9479 9480 if (bbr->rc_allow_data_af_clo == 0) { 9481 close_now: 9482 tcp_log_end_status(tp, TCP_EI_STATUS_DATA_A_CLOSE); 9483 /* tcp_close will kill the inp pre-log the Reset */ 9484 tcp_log_end_status(tp, TCP_EI_STATUS_SERVER_RST); 9485 tp = tcp_close(tp); 9486 KMOD_TCPSTAT_INC(tcps_rcvafterclose); 9487 ctf_do_dropwithreset(m, tp, th, BANDLIM_UNLIMITED, (*tlen)); 9488 return (1); 9489 } 9490 if (sbavail(&so->so_snd) == 0) 9491 goto close_now; 9492 /* Ok we allow data that is ignored and a followup reset */ 9493 tp->rcv_nxt = th->th_seq + *tlen; 9494 tp->t_flags2 |= TF2_DROP_AF_DATA; 9495 bbr->r_wanted_output = 1; 9496 *tlen = 0; 9497 return (0); 9498 } 9499 9500 /* 9501 * Return value of 1, the TCB is unlocked and most 9502 * likely gone, return value of 0, the TCB is still 9503 * locked. 9504 */ 9505 static int 9506 bbr_do_fin_wait_1(struct mbuf *m, struct tcphdr *th, struct socket *so, 9507 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, 9508 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos) 9509 { 9510 int32_t ourfinisacked = 0; 9511 int32_t ret_val; 9512 struct tcp_bbr *bbr; 9513 9514 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 9515 ctf_calc_rwin(so, tp); 9516 if ((thflags & TH_RST) || 9517 (tp->t_fin_is_rst && (thflags & TH_FIN))) 9518 return (ctf_process_rst(m, th, so, tp)); 9519 /* 9520 * RFC5961 Section 4.2 Send challenge ACK for any SYN in 9521 * synchronized state. 9522 */ 9523 if (thflags & TH_SYN) { 9524 ctf_challenge_ack(m, th, tp, &ret_val); 9525 return (ret_val); 9526 } 9527 /* 9528 * RFC 1323 PAWS: If we have a timestamp reply on this segment and 9529 * it's less than ts_recent, drop it. 9530 */ 9531 if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent && 9532 TSTMP_LT(to->to_tsval, tp->ts_recent)) { 9533 if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val)) 9534 return (ret_val); 9535 } 9536 INP_WLOCK_ASSERT(tp->t_inpcb); 9537 if (ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val)) { 9538 return (ret_val); 9539 } 9540 /* 9541 * If new data are received on a connection after the user processes 9542 * are gone, then RST the other end. 9543 */ 9544 if ((so->so_state & SS_NOFDREF) && tlen) { 9545 /* 9546 * We call a new function now so we might continue and setup 9547 * to reset at all data being ack'd. 9548 */ 9549 if (bbr_check_data_after_close(m, bbr, tp, &tlen, th, so)) 9550 return (1); 9551 } 9552 /* 9553 * If last ACK falls within this segment's sequence numbers, record 9554 * its timestamp. NOTE: 1) That the test incorporates suggestions 9555 * from the latest proposal of the tcplw@cray.com list (Braden 9556 * 1993/04/26). 2) That updating only on newer timestamps interferes 9557 * with our earlier PAWS tests, so this check should be solely 9558 * predicated on the sequence space of this segment. 3) That we 9559 * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ 9560 * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ + 9561 * SEG.Len, This modified check allows us to overcome RFC1323's 9562 * limitations as described in Stevens TCP/IP Illustrated Vol. 2 9563 * p.869. In such cases, we can still calculate the RTT correctly 9564 * when RCV.NXT == Last.ACK.Sent. 9565 */ 9566 if ((to->to_flags & TOF_TS) != 0 && 9567 SEQ_LEQ(th->th_seq, tp->last_ack_sent) && 9568 SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen + 9569 ((thflags & (TH_SYN | TH_FIN)) != 0))) { 9570 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv); 9571 tp->ts_recent = to->to_tsval; 9572 } 9573 /* 9574 * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag 9575 * is on (half-synchronized state), then queue data for later 9576 * processing; else drop segment and return. 9577 */ 9578 if ((thflags & TH_ACK) == 0) { 9579 if (tp->t_flags & TF_NEEDSYN) { 9580 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9581 tiwin, thflags, nxt_pkt)); 9582 } else if (tp->t_flags & TF_ACKNOW) { 9583 ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val); 9584 bbr->r_wanted_output = 1; 9585 return (ret_val); 9586 } else { 9587 ctf_do_drop(m, NULL); 9588 return (0); 9589 } 9590 } 9591 /* 9592 * Ack processing. 9593 */ 9594 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val)) { 9595 return (ret_val); 9596 } 9597 if (ourfinisacked) { 9598 /* 9599 * If we can't receive any more data, then closing user can 9600 * proceed. Starting the timer is contrary to the 9601 * specification, but if we don't get a FIN we'll hang 9602 * forever. 9603 * 9604 * XXXjl: we should release the tp also, and use a 9605 * compressed state. 9606 */ 9607 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { 9608 soisdisconnected(so); 9609 tcp_timer_activate(tp, TT_2MSL, 9610 (tcp_fast_finwait2_recycle ? 9611 tcp_finwait2_timeout : 9612 TP_MAXIDLE(tp))); 9613 } 9614 tcp_state_change(tp, TCPS_FIN_WAIT_2); 9615 } 9616 if (sbavail(&so->so_snd)) { 9617 if (ctf_progress_timeout_check(tp, true)) { 9618 bbr_log_progress_event(bbr, tp, tick, PROGRESS_DROP, __LINE__); 9619 ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen); 9620 return (1); 9621 } 9622 } 9623 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9624 tiwin, thflags, nxt_pkt)); 9625 } 9626 9627 /* 9628 * Return value of 1, the TCB is unlocked and most 9629 * likely gone, return value of 0, the TCB is still 9630 * locked. 9631 */ 9632 static int 9633 bbr_do_closing(struct mbuf *m, struct tcphdr *th, struct socket *so, 9634 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, 9635 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos) 9636 { 9637 int32_t ourfinisacked = 0; 9638 int32_t ret_val; 9639 struct tcp_bbr *bbr; 9640 9641 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 9642 ctf_calc_rwin(so, tp); 9643 if ((thflags & TH_RST) || 9644 (tp->t_fin_is_rst && (thflags & TH_FIN))) 9645 return (ctf_process_rst(m, th, so, tp)); 9646 /* 9647 * RFC5961 Section 4.2 Send challenge ACK for any SYN in 9648 * synchronized state. 9649 */ 9650 if (thflags & TH_SYN) { 9651 ctf_challenge_ack(m, th, tp, &ret_val); 9652 return (ret_val); 9653 } 9654 /* 9655 * RFC 1323 PAWS: If we have a timestamp reply on this segment and 9656 * it's less than ts_recent, drop it. 9657 */ 9658 if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent && 9659 TSTMP_LT(to->to_tsval, tp->ts_recent)) { 9660 if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val)) 9661 return (ret_val); 9662 } 9663 INP_WLOCK_ASSERT(tp->t_inpcb); 9664 if (ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val)) { 9665 return (ret_val); 9666 } 9667 /* 9668 * If new data are received on a connection after the user processes 9669 * are gone, then RST the other end. 9670 */ 9671 if ((so->so_state & SS_NOFDREF) && tlen) { 9672 /* 9673 * We call a new function now so we might continue and setup 9674 * to reset at all data being ack'd. 9675 */ 9676 if (bbr_check_data_after_close(m, bbr, tp, &tlen, th, so)) 9677 return (1); 9678 } 9679 /* 9680 * If last ACK falls within this segment's sequence numbers, record 9681 * its timestamp. NOTE: 1) That the test incorporates suggestions 9682 * from the latest proposal of the tcplw@cray.com list (Braden 9683 * 1993/04/26). 2) That updating only on newer timestamps interferes 9684 * with our earlier PAWS tests, so this check should be solely 9685 * predicated on the sequence space of this segment. 3) That we 9686 * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ 9687 * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ + 9688 * SEG.Len, This modified check allows us to overcome RFC1323's 9689 * limitations as described in Stevens TCP/IP Illustrated Vol. 2 9690 * p.869. In such cases, we can still calculate the RTT correctly 9691 * when RCV.NXT == Last.ACK.Sent. 9692 */ 9693 if ((to->to_flags & TOF_TS) != 0 && 9694 SEQ_LEQ(th->th_seq, tp->last_ack_sent) && 9695 SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen + 9696 ((thflags & (TH_SYN | TH_FIN)) != 0))) { 9697 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv); 9698 tp->ts_recent = to->to_tsval; 9699 } 9700 /* 9701 * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag 9702 * is on (half-synchronized state), then queue data for later 9703 * processing; else drop segment and return. 9704 */ 9705 if ((thflags & TH_ACK) == 0) { 9706 if (tp->t_flags & TF_NEEDSYN) { 9707 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9708 tiwin, thflags, nxt_pkt)); 9709 } else if (tp->t_flags & TF_ACKNOW) { 9710 ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val); 9711 bbr->r_wanted_output = 1; 9712 return (ret_val); 9713 } else { 9714 ctf_do_drop(m, NULL); 9715 return (0); 9716 } 9717 } 9718 /* 9719 * Ack processing. 9720 */ 9721 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val)) { 9722 return (ret_val); 9723 } 9724 if (ourfinisacked) { 9725 tcp_twstart(tp); 9726 m_freem(m); 9727 return (1); 9728 } 9729 if (sbavail(&so->so_snd)) { 9730 if (ctf_progress_timeout_check(tp, true)) { 9731 bbr_log_progress_event(bbr, tp, tick, PROGRESS_DROP, __LINE__); 9732 ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen); 9733 return (1); 9734 } 9735 } 9736 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9737 tiwin, thflags, nxt_pkt)); 9738 } 9739 9740 /* 9741 * Return value of 1, the TCB is unlocked and most 9742 * likely gone, return value of 0, the TCB is still 9743 * locked. 9744 */ 9745 static int 9746 bbr_do_lastack(struct mbuf *m, struct tcphdr *th, struct socket *so, 9747 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, 9748 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos) 9749 { 9750 int32_t ourfinisacked = 0; 9751 int32_t ret_val; 9752 struct tcp_bbr *bbr; 9753 9754 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 9755 ctf_calc_rwin(so, tp); 9756 if ((thflags & TH_RST) || 9757 (tp->t_fin_is_rst && (thflags & TH_FIN))) 9758 return (ctf_process_rst(m, th, so, tp)); 9759 /* 9760 * RFC5961 Section 4.2 Send challenge ACK for any SYN in 9761 * synchronized state. 9762 */ 9763 if (thflags & TH_SYN) { 9764 ctf_challenge_ack(m, th, tp, &ret_val); 9765 return (ret_val); 9766 } 9767 /* 9768 * RFC 1323 PAWS: If we have a timestamp reply on this segment and 9769 * it's less than ts_recent, drop it. 9770 */ 9771 if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent && 9772 TSTMP_LT(to->to_tsval, tp->ts_recent)) { 9773 if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val)) 9774 return (ret_val); 9775 } 9776 INP_WLOCK_ASSERT(tp->t_inpcb); 9777 if (ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val)) { 9778 return (ret_val); 9779 } 9780 /* 9781 * If new data are received on a connection after the user processes 9782 * are gone, then RST the other end. 9783 */ 9784 if ((so->so_state & SS_NOFDREF) && tlen) { 9785 /* 9786 * We call a new function now so we might continue and setup 9787 * to reset at all data being ack'd. 9788 */ 9789 if (bbr_check_data_after_close(m, bbr, tp, &tlen, th, so)) 9790 return (1); 9791 } 9792 /* 9793 * If last ACK falls within this segment's sequence numbers, record 9794 * its timestamp. NOTE: 1) That the test incorporates suggestions 9795 * from the latest proposal of the tcplw@cray.com list (Braden 9796 * 1993/04/26). 2) That updating only on newer timestamps interferes 9797 * with our earlier PAWS tests, so this check should be solely 9798 * predicated on the sequence space of this segment. 3) That we 9799 * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ 9800 * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ + 9801 * SEG.Len, This modified check allows us to overcome RFC1323's 9802 * limitations as described in Stevens TCP/IP Illustrated Vol. 2 9803 * p.869. In such cases, we can still calculate the RTT correctly 9804 * when RCV.NXT == Last.ACK.Sent. 9805 */ 9806 if ((to->to_flags & TOF_TS) != 0 && 9807 SEQ_LEQ(th->th_seq, tp->last_ack_sent) && 9808 SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen + 9809 ((thflags & (TH_SYN | TH_FIN)) != 0))) { 9810 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv); 9811 tp->ts_recent = to->to_tsval; 9812 } 9813 /* 9814 * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag 9815 * is on (half-synchronized state), then queue data for later 9816 * processing; else drop segment and return. 9817 */ 9818 if ((thflags & TH_ACK) == 0) { 9819 if (tp->t_flags & TF_NEEDSYN) { 9820 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9821 tiwin, thflags, nxt_pkt)); 9822 } else if (tp->t_flags & TF_ACKNOW) { 9823 ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val); 9824 bbr->r_wanted_output = 1; 9825 return (ret_val); 9826 } else { 9827 ctf_do_drop(m, NULL); 9828 return (0); 9829 } 9830 } 9831 /* 9832 * case TCPS_LAST_ACK: Ack processing. 9833 */ 9834 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val)) { 9835 return (ret_val); 9836 } 9837 if (ourfinisacked) { 9838 tp = tcp_close(tp); 9839 ctf_do_drop(m, tp); 9840 return (1); 9841 } 9842 if (sbavail(&so->so_snd)) { 9843 if (ctf_progress_timeout_check(tp, true)) { 9844 bbr_log_progress_event(bbr, tp, tick, PROGRESS_DROP, __LINE__); 9845 ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen); 9846 return (1); 9847 } 9848 } 9849 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9850 tiwin, thflags, nxt_pkt)); 9851 } 9852 9853 /* 9854 * Return value of 1, the TCB is unlocked and most 9855 * likely gone, return value of 0, the TCB is still 9856 * locked. 9857 */ 9858 static int 9859 bbr_do_fin_wait_2(struct mbuf *m, struct tcphdr *th, struct socket *so, 9860 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen, 9861 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos) 9862 { 9863 int32_t ourfinisacked = 0; 9864 int32_t ret_val; 9865 struct tcp_bbr *bbr; 9866 9867 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 9868 ctf_calc_rwin(so, tp); 9869 /* Reset receive buffer auto scaling when not in bulk receive mode. */ 9870 if ((thflags & TH_RST) || 9871 (tp->t_fin_is_rst && (thflags & TH_FIN))) 9872 return (ctf_process_rst(m, th, so, tp)); 9873 9874 /* 9875 * RFC5961 Section 4.2 Send challenge ACK for any SYN in 9876 * synchronized state. 9877 */ 9878 if (thflags & TH_SYN) { 9879 ctf_challenge_ack(m, th, tp, &ret_val); 9880 return (ret_val); 9881 } 9882 INP_WLOCK_ASSERT(tp->t_inpcb); 9883 /* 9884 * RFC 1323 PAWS: If we have a timestamp reply on this segment and 9885 * it's less than ts_recent, drop it. 9886 */ 9887 if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent && 9888 TSTMP_LT(to->to_tsval, tp->ts_recent)) { 9889 if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val)) 9890 return (ret_val); 9891 } 9892 INP_WLOCK_ASSERT(tp->t_inpcb); 9893 if (ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val)) { 9894 return (ret_val); 9895 } 9896 /* 9897 * If new data are received on a connection after the user processes 9898 * are gone, then we may RST the other end depending on the outcome 9899 * of bbr_check_data_after_close. 9900 */ 9901 if ((so->so_state & SS_NOFDREF) && 9902 tlen) { 9903 /* 9904 * We call a new function now so we might continue and setup 9905 * to reset at all data being ack'd. 9906 */ 9907 if (bbr_check_data_after_close(m, bbr, tp, &tlen, th, so)) 9908 return (1); 9909 } 9910 INP_WLOCK_ASSERT(tp->t_inpcb); 9911 /* 9912 * If last ACK falls within this segment's sequence numbers, record 9913 * its timestamp. NOTE: 1) That the test incorporates suggestions 9914 * from the latest proposal of the tcplw@cray.com list (Braden 9915 * 1993/04/26). 2) That updating only on newer timestamps interferes 9916 * with our earlier PAWS tests, so this check should be solely 9917 * predicated on the sequence space of this segment. 3) That we 9918 * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ 9919 * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ + 9920 * SEG.Len, This modified check allows us to overcome RFC1323's 9921 * limitations as described in Stevens TCP/IP Illustrated Vol. 2 9922 * p.869. In such cases, we can still calculate the RTT correctly 9923 * when RCV.NXT == Last.ACK.Sent. 9924 */ 9925 INP_WLOCK_ASSERT(tp->t_inpcb); 9926 if ((to->to_flags & TOF_TS) != 0 && 9927 SEQ_LEQ(th->th_seq, tp->last_ack_sent) && 9928 SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen + 9929 ((thflags & (TH_SYN | TH_FIN)) != 0))) { 9930 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv); 9931 tp->ts_recent = to->to_tsval; 9932 } 9933 /* 9934 * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag 9935 * is on (half-synchronized state), then queue data for later 9936 * processing; else drop segment and return. 9937 */ 9938 if ((thflags & TH_ACK) == 0) { 9939 if (tp->t_flags & TF_NEEDSYN) { 9940 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9941 tiwin, thflags, nxt_pkt)); 9942 } else if (tp->t_flags & TF_ACKNOW) { 9943 ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val); 9944 bbr->r_wanted_output = 1; 9945 return (ret_val); 9946 } else { 9947 ctf_do_drop(m, NULL); 9948 return (0); 9949 } 9950 } 9951 /* 9952 * Ack processing. 9953 */ 9954 INP_WLOCK_ASSERT(tp->t_inpcb); 9955 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val)) { 9956 return (ret_val); 9957 } 9958 if (sbavail(&so->so_snd)) { 9959 if (ctf_progress_timeout_check(tp, true)) { 9960 bbr_log_progress_event(bbr, tp, tick, PROGRESS_DROP, __LINE__); 9961 ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen); 9962 return (1); 9963 } 9964 } 9965 INP_WLOCK_ASSERT(tp->t_inpcb); 9966 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen, 9967 tiwin, thflags, nxt_pkt)); 9968 } 9969 9970 static void 9971 bbr_stop_all_timers(struct tcpcb *tp) 9972 { 9973 struct tcp_bbr *bbr; 9974 9975 /* 9976 * Assure no timers are running. 9977 */ 9978 if (tcp_timer_active(tp, TT_PERSIST)) { 9979 /* We enter in persists, set the flag appropriately */ 9980 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 9981 bbr->rc_in_persist = 1; 9982 } 9983 tcp_timer_suspend(tp, TT_PERSIST); 9984 tcp_timer_suspend(tp, TT_REXMT); 9985 tcp_timer_suspend(tp, TT_KEEP); 9986 tcp_timer_suspend(tp, TT_DELACK); 9987 } 9988 9989 static void 9990 bbr_google_mode_on(struct tcp_bbr *bbr) 9991 { 9992 bbr->rc_use_google = 1; 9993 bbr->rc_no_pacing = 0; 9994 bbr->r_ctl.bbr_google_discount = bbr_google_discount; 9995 bbr->r_use_policer = bbr_policer_detection_enabled; 9996 bbr->r_ctl.rc_probertt_int = (USECS_IN_SECOND * 10); 9997 bbr->bbr_use_rack_cheat = 0; 9998 bbr->r_ctl.rc_incr_tmrs = 0; 9999 bbr->r_ctl.rc_inc_tcp_oh = 0; 10000 bbr->r_ctl.rc_inc_ip_oh = 0; 10001 bbr->r_ctl.rc_inc_enet_oh = 0; 10002 reset_time(&bbr->r_ctl.rc_delrate, 10003 BBR_NUM_RTTS_FOR_GOOG_DEL_LIMIT); 10004 reset_time_small(&bbr->r_ctl.rc_rttprop, 10005 (11 * USECS_IN_SECOND)); 10006 tcp_bbr_tso_size_check(bbr, tcp_get_usecs(&bbr->rc_tv)); 10007 } 10008 10009 static void 10010 bbr_google_mode_off(struct tcp_bbr *bbr) 10011 { 10012 bbr->rc_use_google = 0; 10013 bbr->r_ctl.bbr_google_discount = 0; 10014 bbr->no_pacing_until = bbr_no_pacing_until; 10015 bbr->r_use_policer = 0; 10016 if (bbr->no_pacing_until) 10017 bbr->rc_no_pacing = 1; 10018 else 10019 bbr->rc_no_pacing = 0; 10020 if (bbr_use_rack_resend_cheat) 10021 bbr->bbr_use_rack_cheat = 1; 10022 else 10023 bbr->bbr_use_rack_cheat = 0; 10024 if (bbr_incr_timers) 10025 bbr->r_ctl.rc_incr_tmrs = 1; 10026 else 10027 bbr->r_ctl.rc_incr_tmrs = 0; 10028 if (bbr_include_tcp_oh) 10029 bbr->r_ctl.rc_inc_tcp_oh = 1; 10030 else 10031 bbr->r_ctl.rc_inc_tcp_oh = 0; 10032 if (bbr_include_ip_oh) 10033 bbr->r_ctl.rc_inc_ip_oh = 1; 10034 else 10035 bbr->r_ctl.rc_inc_ip_oh = 0; 10036 if (bbr_include_enet_oh) 10037 bbr->r_ctl.rc_inc_enet_oh = 1; 10038 else 10039 bbr->r_ctl.rc_inc_enet_oh = 0; 10040 bbr->r_ctl.rc_probertt_int = bbr_rtt_probe_limit; 10041 reset_time(&bbr->r_ctl.rc_delrate, 10042 bbr_num_pktepo_for_del_limit); 10043 reset_time_small(&bbr->r_ctl.rc_rttprop, 10044 (bbr_filter_len_sec * USECS_IN_SECOND)); 10045 tcp_bbr_tso_size_check(bbr, tcp_get_usecs(&bbr->rc_tv)); 10046 } 10047 /* 10048 * Return 0 on success, non-zero on failure 10049 * which indicates the error (usually no memory). 10050 */ 10051 static int 10052 bbr_init(struct tcpcb *tp) 10053 { 10054 struct tcp_bbr *bbr = NULL; 10055 struct inpcb *inp; 10056 uint32_t cts; 10057 10058 tp->t_fb_ptr = uma_zalloc(bbr_pcb_zone, (M_NOWAIT | M_ZERO)); 10059 if (tp->t_fb_ptr == NULL) { 10060 /* 10061 * We need to allocate memory but cant. The INP and INP_INFO 10062 * locks and they are recusive (happens during setup. So a 10063 * scheme to drop the locks fails :( 10064 * 10065 */ 10066 return (ENOMEM); 10067 } 10068 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 10069 bbr->rtt_valid = 0; 10070 inp = tp->t_inpcb; 10071 inp->inp_flags2 |= INP_CANNOT_DO_ECN; 10072 inp->inp_flags2 |= INP_SUPPORTS_MBUFQ; 10073 TAILQ_INIT(&bbr->r_ctl.rc_map); 10074 TAILQ_INIT(&bbr->r_ctl.rc_free); 10075 TAILQ_INIT(&bbr->r_ctl.rc_tmap); 10076 bbr->rc_tp = tp; 10077 if (tp->t_inpcb) { 10078 bbr->rc_inp = tp->t_inpcb; 10079 } 10080 cts = tcp_get_usecs(&bbr->rc_tv); 10081 tp->t_acktime = 0; 10082 bbr->rc_allow_data_af_clo = bbr_ignore_data_after_close; 10083 bbr->r_ctl.rc_reorder_fade = bbr_reorder_fade; 10084 bbr->rc_tlp_threshold = bbr_tlp_thresh; 10085 bbr->r_ctl.rc_reorder_shift = bbr_reorder_thresh; 10086 bbr->r_ctl.rc_pkt_delay = bbr_pkt_delay; 10087 bbr->r_ctl.rc_min_to = bbr_min_to; 10088 bbr->rc_bbr_state = BBR_STATE_STARTUP; 10089 bbr->r_ctl.bbr_lost_at_state = 0; 10090 bbr->r_ctl.rc_lost_at_startup = 0; 10091 bbr->rc_all_timers_stopped = 0; 10092 bbr->r_ctl.rc_bbr_lastbtlbw = 0; 10093 bbr->r_ctl.rc_pkt_epoch_del = 0; 10094 bbr->r_ctl.rc_pkt_epoch = 0; 10095 bbr->r_ctl.rc_lowest_rtt = 0xffffffff; 10096 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_high_gain; 10097 bbr->r_ctl.rc_bbr_cwnd_gain = bbr_high_gain; 10098 bbr->r_ctl.rc_went_idle_time = cts; 10099 bbr->rc_pacer_started = cts; 10100 bbr->r_ctl.rc_pkt_epoch_time = cts; 10101 bbr->r_ctl.rc_rcvtime = cts; 10102 bbr->r_ctl.rc_bbr_state_time = cts; 10103 bbr->r_ctl.rc_del_time = cts; 10104 bbr->r_ctl.rc_tlp_rxt_last_time = cts; 10105 bbr->r_ctl.last_in_probertt = cts; 10106 bbr->skip_gain = 0; 10107 bbr->gain_is_limited = 0; 10108 bbr->no_pacing_until = bbr_no_pacing_until; 10109 if (bbr->no_pacing_until) 10110 bbr->rc_no_pacing = 1; 10111 if (bbr_use_google_algo) { 10112 bbr->rc_no_pacing = 0; 10113 bbr->rc_use_google = 1; 10114 bbr->r_ctl.bbr_google_discount = bbr_google_discount; 10115 bbr->r_use_policer = bbr_policer_detection_enabled; 10116 } else { 10117 bbr->rc_use_google = 0; 10118 bbr->r_ctl.bbr_google_discount = 0; 10119 bbr->r_use_policer = 0; 10120 } 10121 if (bbr_ts_limiting) 10122 bbr->rc_use_ts_limit = 1; 10123 else 10124 bbr->rc_use_ts_limit = 0; 10125 if (bbr_ts_can_raise) 10126 bbr->ts_can_raise = 1; 10127 else 10128 bbr->ts_can_raise = 0; 10129 if (V_tcp_delack_enabled == 1) 10130 tp->t_delayed_ack = 2; 10131 else if (V_tcp_delack_enabled == 0) 10132 tp->t_delayed_ack = 0; 10133 else if (V_tcp_delack_enabled < 100) 10134 tp->t_delayed_ack = V_tcp_delack_enabled; 10135 else 10136 tp->t_delayed_ack = 2; 10137 if (bbr->rc_use_google == 0) 10138 bbr->r_ctl.rc_probertt_int = bbr_rtt_probe_limit; 10139 else 10140 bbr->r_ctl.rc_probertt_int = (USECS_IN_SECOND * 10); 10141 bbr->r_ctl.rc_min_rto_ms = bbr_rto_min_ms; 10142 bbr->rc_max_rto_sec = bbr_rto_max_sec; 10143 bbr->rc_init_win = bbr_def_init_win; 10144 if (tp->t_flags & TF_REQ_TSTMP) 10145 bbr->rc_last_options = TCP_TS_OVERHEAD; 10146 bbr->r_ctl.rc_pace_max_segs = tp->t_maxseg - bbr->rc_last_options; 10147 bbr->r_ctl.rc_high_rwnd = tp->snd_wnd; 10148 bbr->r_init_rtt = 1; 10149 10150 counter_u64_add(bbr_flows_nohdwr_pacing, 1); 10151 if (bbr_allow_hdwr_pacing) 10152 bbr->bbr_hdw_pace_ena = 1; 10153 else 10154 bbr->bbr_hdw_pace_ena = 0; 10155 if (bbr_sends_full_iwnd) 10156 bbr->bbr_init_win_cheat = 1; 10157 else 10158 bbr->bbr_init_win_cheat = 0; 10159 bbr->r_ctl.bbr_utter_max = bbr_hptsi_utter_max; 10160 bbr->r_ctl.rc_drain_pg = bbr_drain_gain; 10161 bbr->r_ctl.rc_startup_pg = bbr_high_gain; 10162 bbr->rc_loss_exit = bbr_exit_startup_at_loss; 10163 bbr->r_ctl.bbr_rttprobe_gain_val = bbr_rttprobe_gain; 10164 bbr->r_ctl.bbr_hptsi_per_second = bbr_hptsi_per_second; 10165 bbr->r_ctl.bbr_hptsi_segments_delay_tar = bbr_hptsi_segments_delay_tar; 10166 bbr->r_ctl.bbr_hptsi_segments_max = bbr_hptsi_segments_max; 10167 bbr->r_ctl.bbr_hptsi_segments_floor = bbr_hptsi_segments_floor; 10168 bbr->r_ctl.bbr_hptsi_bytes_min = bbr_hptsi_bytes_min; 10169 bbr->r_ctl.bbr_cross_over = bbr_cross_over; 10170 bbr->r_ctl.rc_rtt_shrinks = cts; 10171 if (bbr->rc_use_google) { 10172 setup_time_filter(&bbr->r_ctl.rc_delrate, 10173 FILTER_TYPE_MAX, 10174 BBR_NUM_RTTS_FOR_GOOG_DEL_LIMIT); 10175 setup_time_filter_small(&bbr->r_ctl.rc_rttprop, 10176 FILTER_TYPE_MIN, (11 * USECS_IN_SECOND)); 10177 } else { 10178 setup_time_filter(&bbr->r_ctl.rc_delrate, 10179 FILTER_TYPE_MAX, 10180 bbr_num_pktepo_for_del_limit); 10181 setup_time_filter_small(&bbr->r_ctl.rc_rttprop, 10182 FILTER_TYPE_MIN, (bbr_filter_len_sec * USECS_IN_SECOND)); 10183 } 10184 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_INIT, 0); 10185 if (bbr_uses_idle_restart) 10186 bbr->rc_use_idle_restart = 1; 10187 else 10188 bbr->rc_use_idle_restart = 0; 10189 bbr->r_ctl.rc_bbr_cur_del_rate = 0; 10190 bbr->r_ctl.rc_initial_hptsi_bw = bbr_initial_bw_bps; 10191 if (bbr_resends_use_tso) 10192 bbr->rc_resends_use_tso = 1; 10193 #ifdef NETFLIX_PEAKRATE 10194 tp->t_peakrate_thr = tp->t_maxpeakrate; 10195 #endif 10196 if (tp->snd_una != tp->snd_max) { 10197 /* Create a send map for the current outstanding data */ 10198 struct bbr_sendmap *rsm; 10199 10200 rsm = bbr_alloc(bbr); 10201 if (rsm == NULL) { 10202 uma_zfree(bbr_pcb_zone, tp->t_fb_ptr); 10203 tp->t_fb_ptr = NULL; 10204 return (ENOMEM); 10205 } 10206 rsm->r_flags = BBR_OVERMAX; 10207 rsm->r_tim_lastsent[0] = cts; 10208 rsm->r_rtr_cnt = 1; 10209 rsm->r_rtr_bytes = 0; 10210 rsm->r_start = tp->snd_una; 10211 rsm->r_end = tp->snd_max; 10212 rsm->r_dupack = 0; 10213 rsm->r_delivered = bbr->r_ctl.rc_delivered; 10214 rsm->r_ts_valid = 0; 10215 rsm->r_del_ack_ts = tp->ts_recent; 10216 rsm->r_del_time = cts; 10217 if (bbr->r_ctl.r_app_limited_until) 10218 rsm->r_app_limited = 1; 10219 else 10220 rsm->r_app_limited = 0; 10221 TAILQ_INSERT_TAIL(&bbr->r_ctl.rc_map, rsm, r_next); 10222 TAILQ_INSERT_TAIL(&bbr->r_ctl.rc_tmap, rsm, r_tnext); 10223 rsm->r_in_tmap = 1; 10224 if (bbr->rc_bbr_state == BBR_STATE_PROBE_BW) 10225 rsm->r_bbr_state = bbr_state_val(bbr); 10226 else 10227 rsm->r_bbr_state = 8; 10228 } 10229 if (bbr_use_rack_resend_cheat && (bbr->rc_use_google == 0)) 10230 bbr->bbr_use_rack_cheat = 1; 10231 if (bbr_incr_timers && (bbr->rc_use_google == 0)) 10232 bbr->r_ctl.rc_incr_tmrs = 1; 10233 if (bbr_include_tcp_oh && (bbr->rc_use_google == 0)) 10234 bbr->r_ctl.rc_inc_tcp_oh = 1; 10235 if (bbr_include_ip_oh && (bbr->rc_use_google == 0)) 10236 bbr->r_ctl.rc_inc_ip_oh = 1; 10237 if (bbr_include_enet_oh && (bbr->rc_use_google == 0)) 10238 bbr->r_ctl.rc_inc_enet_oh = 1; 10239 10240 bbr_log_type_statechange(bbr, cts, __LINE__); 10241 if (TCPS_HAVEESTABLISHED(tp->t_state) && 10242 (tp->t_srtt)) { 10243 uint32_t rtt; 10244 10245 rtt = (TICKS_2_USEC(tp->t_srtt) >> TCP_RTT_SHIFT); 10246 apply_filter_min_small(&bbr->r_ctl.rc_rttprop, rtt, cts); 10247 } 10248 /* announce the settings and state */ 10249 bbr_log_settings_change(bbr, BBR_RECOVERY_LOWRTT); 10250 tcp_bbr_tso_size_check(bbr, cts); 10251 /* 10252 * Now call the generic function to start a timer. This will place 10253 * the TCB on the hptsi wheel if a timer is needed with appropriate 10254 * flags. 10255 */ 10256 bbr_stop_all_timers(tp); 10257 bbr_start_hpts_timer(bbr, tp, cts, 5, 0, 0); 10258 return (0); 10259 } 10260 10261 /* 10262 * Return 0 if we can accept the connection. Return 10263 * non-zero if we can't handle the connection. A EAGAIN 10264 * means you need to wait until the connection is up. 10265 * a EADDRNOTAVAIL means we can never handle the connection 10266 * (no SACK). 10267 */ 10268 static int 10269 bbr_handoff_ok(struct tcpcb *tp) 10270 { 10271 if ((tp->t_state == TCPS_CLOSED) || 10272 (tp->t_state == TCPS_LISTEN)) { 10273 /* Sure no problem though it may not stick */ 10274 return (0); 10275 } 10276 if ((tp->t_state == TCPS_SYN_SENT) || 10277 (tp->t_state == TCPS_SYN_RECEIVED)) { 10278 /* 10279 * We really don't know you have to get to ESTAB or beyond 10280 * to tell. 10281 */ 10282 return (EAGAIN); 10283 } 10284 if (tp->t_flags & TF_SENTFIN) 10285 return (EINVAL); 10286 if ((tp->t_flags & TF_SACK_PERMIT) || bbr_sack_not_required) { 10287 return (0); 10288 } 10289 /* 10290 * If we reach here we don't do SACK on this connection so we can 10291 * never do rack. 10292 */ 10293 return (EINVAL); 10294 } 10295 10296 static void 10297 bbr_fini(struct tcpcb *tp, int32_t tcb_is_purged) 10298 { 10299 if (tp->t_fb_ptr) { 10300 uint32_t calc; 10301 struct tcp_bbr *bbr; 10302 struct bbr_sendmap *rsm; 10303 10304 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 10305 if (bbr->r_ctl.crte) 10306 tcp_rel_pacing_rate(bbr->r_ctl.crte, bbr->rc_tp); 10307 bbr_log_flowend(bbr); 10308 bbr->rc_tp = NULL; 10309 if (tp->t_inpcb) { 10310 /* Backout any flags2 we applied */ 10311 tp->t_inpcb->inp_flags2 &= ~INP_CANNOT_DO_ECN; 10312 tp->t_inpcb->inp_flags2 &= ~INP_SUPPORTS_MBUFQ; 10313 tp->t_inpcb->inp_flags2 &= ~INP_MBUF_QUEUE_READY; 10314 } 10315 if (bbr->bbr_hdrw_pacing) 10316 counter_u64_add(bbr_flows_whdwr_pacing, -1); 10317 else 10318 counter_u64_add(bbr_flows_nohdwr_pacing, -1); 10319 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map); 10320 while (rsm) { 10321 TAILQ_REMOVE(&bbr->r_ctl.rc_map, rsm, r_next); 10322 uma_zfree(bbr_zone, rsm); 10323 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map); 10324 } 10325 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_free); 10326 while (rsm) { 10327 TAILQ_REMOVE(&bbr->r_ctl.rc_free, rsm, r_next); 10328 uma_zfree(bbr_zone, rsm); 10329 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_free); 10330 } 10331 calc = bbr->r_ctl.rc_high_rwnd - bbr->r_ctl.rc_init_rwnd; 10332 if (calc > (bbr->r_ctl.rc_init_rwnd / 10)) 10333 BBR_STAT_INC(bbr_dynamic_rwnd); 10334 else 10335 BBR_STAT_INC(bbr_static_rwnd); 10336 bbr->r_ctl.rc_free_cnt = 0; 10337 uma_zfree(bbr_pcb_zone, tp->t_fb_ptr); 10338 tp->t_fb_ptr = NULL; 10339 } 10340 /* Make sure snd_nxt is correctly set */ 10341 tp->snd_nxt = tp->snd_max; 10342 } 10343 10344 static void 10345 bbr_set_state(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t win) 10346 { 10347 switch (tp->t_state) { 10348 case TCPS_SYN_SENT: 10349 bbr->r_state = TCPS_SYN_SENT; 10350 bbr->r_substate = bbr_do_syn_sent; 10351 break; 10352 case TCPS_SYN_RECEIVED: 10353 bbr->r_state = TCPS_SYN_RECEIVED; 10354 bbr->r_substate = bbr_do_syn_recv; 10355 break; 10356 case TCPS_ESTABLISHED: 10357 bbr->r_ctl.rc_init_rwnd = max(win, bbr->rc_tp->snd_wnd); 10358 bbr->r_state = TCPS_ESTABLISHED; 10359 bbr->r_substate = bbr_do_established; 10360 break; 10361 case TCPS_CLOSE_WAIT: 10362 bbr->r_state = TCPS_CLOSE_WAIT; 10363 bbr->r_substate = bbr_do_close_wait; 10364 break; 10365 case TCPS_FIN_WAIT_1: 10366 bbr->r_state = TCPS_FIN_WAIT_1; 10367 bbr->r_substate = bbr_do_fin_wait_1; 10368 break; 10369 case TCPS_CLOSING: 10370 bbr->r_state = TCPS_CLOSING; 10371 bbr->r_substate = bbr_do_closing; 10372 break; 10373 case TCPS_LAST_ACK: 10374 bbr->r_state = TCPS_LAST_ACK; 10375 bbr->r_substate = bbr_do_lastack; 10376 break; 10377 case TCPS_FIN_WAIT_2: 10378 bbr->r_state = TCPS_FIN_WAIT_2; 10379 bbr->r_substate = bbr_do_fin_wait_2; 10380 break; 10381 case TCPS_LISTEN: 10382 case TCPS_CLOSED: 10383 case TCPS_TIME_WAIT: 10384 default: 10385 break; 10386 }; 10387 } 10388 10389 static void 10390 bbr_substate_change(struct tcp_bbr *bbr, uint32_t cts, int32_t line, int dolog) 10391 { 10392 /* 10393 * Now what state are we going into now? Is there adjustments 10394 * needed? 10395 */ 10396 int32_t old_state, old_gain; 10397 10398 old_state = bbr_state_val(bbr); 10399 old_gain = bbr->r_ctl.rc_bbr_hptsi_gain; 10400 if (bbr_state_val(bbr) == BBR_SUB_LEVEL1) { 10401 /* Save the lowest srtt we saw in our end of the sub-state */ 10402 bbr->rc_hit_state_1 = 0; 10403 if (bbr->r_ctl.bbr_smallest_srtt_this_state != 0xffffffff) 10404 bbr->r_ctl.bbr_smallest_srtt_state2 = bbr->r_ctl.bbr_smallest_srtt_this_state; 10405 } 10406 bbr->rc_bbr_substate++; 10407 if (bbr->rc_bbr_substate >= BBR_SUBSTATE_COUNT) { 10408 /* Cycle back to first state-> gain */ 10409 bbr->rc_bbr_substate = 0; 10410 } 10411 if (bbr_state_val(bbr) == BBR_SUB_GAIN) { 10412 /* 10413 * We enter the gain(5/4) cycle (possibly less if 10414 * shallow buffer detection is enabled) 10415 */ 10416 if (bbr->skip_gain) { 10417 /* 10418 * Hardware pacing has set our rate to 10419 * the max and limited our b/w just 10420 * do level i.e. no gain. 10421 */ 10422 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_hptsi_gain[BBR_SUB_LEVEL1]; 10423 } else if (bbr->gain_is_limited && 10424 bbr->bbr_hdrw_pacing && 10425 bbr->r_ctl.crte) { 10426 /* 10427 * We can't gain above the hardware pacing 10428 * rate which is less than our rate + the gain 10429 * calculate the gain needed to reach the hardware 10430 * pacing rate.. 10431 */ 10432 uint64_t bw, rate, gain_calc; 10433 10434 bw = bbr_get_bw(bbr); 10435 rate = bbr->r_ctl.crte->rate; 10436 if ((rate > bw) && 10437 (((bw * (uint64_t)bbr_hptsi_gain[BBR_SUB_GAIN]) / (uint64_t)BBR_UNIT) > rate)) { 10438 gain_calc = (rate * BBR_UNIT) / bw; 10439 if (gain_calc < BBR_UNIT) 10440 gain_calc = BBR_UNIT; 10441 bbr->r_ctl.rc_bbr_hptsi_gain = (uint16_t)gain_calc; 10442 } else { 10443 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_hptsi_gain[BBR_SUB_GAIN]; 10444 } 10445 } else 10446 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_hptsi_gain[BBR_SUB_GAIN]; 10447 if ((bbr->rc_use_google == 0) && (bbr_gain_to_target == 0)) { 10448 bbr->r_ctl.rc_bbr_state_atflight = cts; 10449 } else 10450 bbr->r_ctl.rc_bbr_state_atflight = 0; 10451 } else if (bbr_state_val(bbr) == BBR_SUB_DRAIN) { 10452 bbr->rc_hit_state_1 = 1; 10453 bbr->r_ctl.rc_exta_time_gd = 0; 10454 bbr->r_ctl.flightsize_at_drain = ctf_flight_size(bbr->rc_tp, 10455 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 10456 if (bbr_state_drain_2_tar) { 10457 bbr->r_ctl.rc_bbr_state_atflight = 0; 10458 } else 10459 bbr->r_ctl.rc_bbr_state_atflight = cts; 10460 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_hptsi_gain[BBR_SUB_DRAIN]; 10461 } else { 10462 /* All other cycles hit here 2-7 */ 10463 if ((old_state == BBR_SUB_DRAIN) && bbr->rc_hit_state_1) { 10464 if (bbr_sub_drain_slam_cwnd && 10465 (bbr->rc_use_google == 0) && 10466 (bbr->rc_tp->snd_cwnd < bbr->r_ctl.rc_saved_cwnd)) { 10467 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_saved_cwnd; 10468 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 10469 } 10470 if ((cts - bbr->r_ctl.rc_bbr_state_time) > bbr_get_rtt(bbr, BBR_RTT_PROP)) 10471 bbr->r_ctl.rc_exta_time_gd += ((cts - bbr->r_ctl.rc_bbr_state_time) - 10472 bbr_get_rtt(bbr, BBR_RTT_PROP)); 10473 else 10474 bbr->r_ctl.rc_exta_time_gd = 0; 10475 if (bbr->r_ctl.rc_exta_time_gd) { 10476 bbr->r_ctl.rc_level_state_extra = bbr->r_ctl.rc_exta_time_gd; 10477 /* Now chop up the time for each state (div by 7) */ 10478 bbr->r_ctl.rc_level_state_extra /= 7; 10479 if (bbr_rand_ot && bbr->r_ctl.rc_level_state_extra) { 10480 /* Add a randomization */ 10481 bbr_randomize_extra_state_time(bbr); 10482 } 10483 } 10484 } 10485 bbr->r_ctl.rc_bbr_state_atflight = max(1, cts); 10486 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_hptsi_gain[bbr_state_val(bbr)]; 10487 } 10488 if (bbr->rc_use_google) { 10489 bbr->r_ctl.rc_bbr_state_atflight = max(1, cts); 10490 } 10491 bbr->r_ctl.bbr_lost_at_state = bbr->r_ctl.rc_lost; 10492 bbr->r_ctl.rc_bbr_cwnd_gain = bbr_cwnd_gain; 10493 if (dolog) 10494 bbr_log_type_statechange(bbr, cts, line); 10495 10496 if (SEQ_GT(cts, bbr->r_ctl.rc_bbr_state_time)) { 10497 uint32_t time_in; 10498 10499 time_in = cts - bbr->r_ctl.rc_bbr_state_time; 10500 if (bbr->rc_bbr_state == BBR_STATE_PROBE_BW) { 10501 counter_u64_add(bbr_state_time[(old_state + 5)], time_in); 10502 } else { 10503 counter_u64_add(bbr_state_time[bbr->rc_bbr_state], time_in); 10504 } 10505 } 10506 bbr->r_ctl.bbr_smallest_srtt_this_state = 0xffffffff; 10507 bbr_set_state_target(bbr, __LINE__); 10508 if (bbr_sub_drain_slam_cwnd && 10509 (bbr->rc_use_google == 0) && 10510 (bbr_state_val(bbr) == BBR_SUB_DRAIN)) { 10511 /* Slam down the cwnd */ 10512 bbr->r_ctl.rc_saved_cwnd = bbr->rc_tp->snd_cwnd; 10513 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_target_at_state; 10514 if (bbr_sub_drain_app_limit) { 10515 /* Go app limited if we are on a long drain */ 10516 bbr->r_ctl.r_app_limited_until = (bbr->r_ctl.rc_delivered + 10517 ctf_flight_size(bbr->rc_tp, 10518 (bbr->r_ctl.rc_sacked + 10519 bbr->r_ctl.rc_lost_bytes))); 10520 } 10521 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 10522 } 10523 if (bbr->rc_lt_use_bw) { 10524 /* In policed mode we clamp pacing_gain to BBR_UNIT */ 10525 bbr->r_ctl.rc_bbr_hptsi_gain = BBR_UNIT; 10526 } 10527 /* Google changes TSO size every cycle */ 10528 if (bbr->rc_use_google) 10529 tcp_bbr_tso_size_check(bbr, cts); 10530 bbr->r_ctl.gain_epoch = cts; 10531 bbr->r_ctl.rc_bbr_state_time = cts; 10532 bbr->r_ctl.substate_pe = bbr->r_ctl.rc_pkt_epoch; 10533 } 10534 10535 static void 10536 bbr_set_probebw_google_gains(struct tcp_bbr *bbr, uint32_t cts, uint32_t losses) 10537 { 10538 if ((bbr_state_val(bbr) == BBR_SUB_DRAIN) && 10539 (google_allow_early_out == 1) && 10540 (bbr->r_ctl.rc_flight_at_input <= bbr->r_ctl.rc_target_at_state)) { 10541 /* We have reached out target flight size possibly early */ 10542 goto change_state; 10543 } 10544 if (TSTMP_LT(cts, bbr->r_ctl.rc_bbr_state_time)) { 10545 return; 10546 } 10547 if ((cts - bbr->r_ctl.rc_bbr_state_time) < bbr_get_rtt(bbr, BBR_RTT_PROP)) { 10548 /* 10549 * Must be a rttProp movement forward before 10550 * we can change states. 10551 */ 10552 return; 10553 } 10554 if (bbr_state_val(bbr) == BBR_SUB_GAIN) { 10555 /* 10556 * The needed time has passed but for 10557 * the gain cycle extra rules apply: 10558 * 1) If we have seen loss, we exit 10559 * 2) If we have not reached the target 10560 * we stay in GAIN (gain-to-target). 10561 */ 10562 if (google_consider_lost && losses) 10563 goto change_state; 10564 if (bbr->r_ctl.rc_target_at_state > bbr->r_ctl.rc_flight_at_input) { 10565 return; 10566 } 10567 } 10568 change_state: 10569 /* For gain we must reach our target, all others last 1 rttProp */ 10570 bbr_substate_change(bbr, cts, __LINE__, 1); 10571 } 10572 10573 static void 10574 bbr_set_probebw_gains(struct tcp_bbr *bbr, uint32_t cts, uint32_t losses) 10575 { 10576 uint32_t flight, bbr_cur_cycle_time; 10577 10578 if (bbr->rc_use_google) { 10579 bbr_set_probebw_google_gains(bbr, cts, losses); 10580 return; 10581 } 10582 if (cts == 0) { 10583 /* 10584 * Never alow cts to be 0 we 10585 * do this so we can judge if 10586 * we have set a timestamp. 10587 */ 10588 cts = 1; 10589 } 10590 if (bbr_state_is_pkt_epoch) 10591 bbr_cur_cycle_time = bbr_get_rtt(bbr, BBR_RTT_PKTRTT); 10592 else 10593 bbr_cur_cycle_time = bbr_get_rtt(bbr, BBR_RTT_PROP); 10594 10595 if (bbr->r_ctl.rc_bbr_state_atflight == 0) { 10596 if (bbr_state_val(bbr) == BBR_SUB_DRAIN) { 10597 flight = ctf_flight_size(bbr->rc_tp, 10598 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 10599 if (bbr_sub_drain_slam_cwnd && bbr->rc_hit_state_1) { 10600 /* Keep it slam down */ 10601 if (bbr->rc_tp->snd_cwnd > bbr->r_ctl.rc_target_at_state) { 10602 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_target_at_state; 10603 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 10604 } 10605 if (bbr_sub_drain_app_limit) { 10606 /* Go app limited if we are on a long drain */ 10607 bbr->r_ctl.r_app_limited_until = (bbr->r_ctl.rc_delivered + flight); 10608 } 10609 } 10610 if (TSTMP_GT(cts, bbr->r_ctl.gain_epoch) && 10611 (((cts - bbr->r_ctl.gain_epoch) > bbr_get_rtt(bbr, BBR_RTT_PROP)) || 10612 (flight >= bbr->r_ctl.flightsize_at_drain))) { 10613 /* 10614 * Still here after the same time as 10615 * the gain. We need to drain harder 10616 * for the next srtt. Reduce by a set amount 10617 * the gain drop is capped at DRAIN states 10618 * value (88). 10619 */ 10620 bbr->r_ctl.flightsize_at_drain = flight; 10621 if (bbr_drain_drop_mul && 10622 bbr_drain_drop_div && 10623 (bbr_drain_drop_mul < bbr_drain_drop_div)) { 10624 /* Use your specific drop value (def 4/5 = 20%) */ 10625 bbr->r_ctl.rc_bbr_hptsi_gain *= bbr_drain_drop_mul; 10626 bbr->r_ctl.rc_bbr_hptsi_gain /= bbr_drain_drop_div; 10627 } else { 10628 /* You get drop of 20% */ 10629 bbr->r_ctl.rc_bbr_hptsi_gain *= 4; 10630 bbr->r_ctl.rc_bbr_hptsi_gain /= 5; 10631 } 10632 if (bbr->r_ctl.rc_bbr_hptsi_gain <= bbr_drain_floor) { 10633 /* Reduce our gain again to the bottom */ 10634 bbr->r_ctl.rc_bbr_hptsi_gain = max(bbr_drain_floor, 1); 10635 } 10636 bbr_log_exit_gain(bbr, cts, 4); 10637 /* 10638 * Extend out so we wait another 10639 * epoch before dropping again. 10640 */ 10641 bbr->r_ctl.gain_epoch = cts; 10642 } 10643 if (flight <= bbr->r_ctl.rc_target_at_state) { 10644 if (bbr_sub_drain_slam_cwnd && 10645 (bbr->rc_use_google == 0) && 10646 (bbr->rc_tp->snd_cwnd < bbr->r_ctl.rc_saved_cwnd)) { 10647 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_saved_cwnd; 10648 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 10649 } 10650 bbr->r_ctl.rc_bbr_state_atflight = max(cts, 1); 10651 bbr_log_exit_gain(bbr, cts, 3); 10652 } 10653 } else { 10654 /* Its a gain */ 10655 if (bbr->r_ctl.rc_lost > bbr->r_ctl.bbr_lost_at_state) { 10656 bbr->r_ctl.rc_bbr_state_atflight = max(cts, 1); 10657 goto change_state; 10658 } 10659 if ((ctf_outstanding(bbr->rc_tp) >= bbr->r_ctl.rc_target_at_state) || 10660 ((ctf_outstanding(bbr->rc_tp) + bbr->rc_tp->t_maxseg - 1) >= 10661 bbr->rc_tp->snd_wnd)) { 10662 bbr->r_ctl.rc_bbr_state_atflight = max(cts, 1); 10663 bbr_log_exit_gain(bbr, cts, 2); 10664 } 10665 } 10666 /** 10667 * We fall through and return always one of two things has 10668 * occured. 10669 * 1) We are still not at target 10670 * <or> 10671 * 2) We reached the target and set rc_bbr_state_atflight 10672 * which means we no longer hit this block 10673 * next time we are called. 10674 */ 10675 return; 10676 } 10677 change_state: 10678 if (TSTMP_LT(cts, bbr->r_ctl.rc_bbr_state_time)) 10679 return; 10680 if ((cts - bbr->r_ctl.rc_bbr_state_time) < bbr_cur_cycle_time) { 10681 /* Less than a full time-period has passed */ 10682 return; 10683 } 10684 if (bbr->r_ctl.rc_level_state_extra && 10685 (bbr_state_val(bbr) > BBR_SUB_DRAIN) && 10686 ((cts - bbr->r_ctl.rc_bbr_state_time) < 10687 (bbr_cur_cycle_time + bbr->r_ctl.rc_level_state_extra))) { 10688 /* Less than a full time-period + extra has passed */ 10689 return; 10690 } 10691 if (bbr_gain_gets_extra_too && 10692 bbr->r_ctl.rc_level_state_extra && 10693 (bbr_state_val(bbr) == BBR_SUB_GAIN) && 10694 ((cts - bbr->r_ctl.rc_bbr_state_time) < 10695 (bbr_cur_cycle_time + bbr->r_ctl.rc_level_state_extra))) { 10696 /* Less than a full time-period + extra has passed */ 10697 return; 10698 } 10699 bbr_substate_change(bbr, cts, __LINE__, 1); 10700 } 10701 10702 static uint32_t 10703 bbr_get_a_state_target(struct tcp_bbr *bbr, uint32_t gain) 10704 { 10705 uint32_t mss, tar; 10706 10707 if (bbr->rc_use_google) { 10708 /* Google just uses the cwnd target */ 10709 tar = bbr_get_target_cwnd(bbr, bbr_get_bw(bbr), gain); 10710 } else { 10711 mss = min((bbr->rc_tp->t_maxseg - bbr->rc_last_options), 10712 bbr->r_ctl.rc_pace_max_segs); 10713 /* Get the base cwnd with gain rounded to a mss */ 10714 tar = roundup(bbr_get_raw_target_cwnd(bbr, bbr_get_bw(bbr), 10715 gain), mss); 10716 /* Make sure it is within our min */ 10717 if (tar < get_min_cwnd(bbr)) 10718 return (get_min_cwnd(bbr)); 10719 } 10720 return (tar); 10721 } 10722 10723 static void 10724 bbr_set_state_target(struct tcp_bbr *bbr, int line) 10725 { 10726 uint32_t tar, meth; 10727 10728 if ((bbr->rc_bbr_state == BBR_STATE_PROBE_RTT) && 10729 ((bbr->r_ctl.bbr_rttprobe_gain_val == 0) || bbr->rc_use_google)) { 10730 /* Special case using old probe-rtt method */ 10731 tar = bbr_rtt_probe_cwndtarg * (bbr->rc_tp->t_maxseg - bbr->rc_last_options); 10732 meth = 1; 10733 } else { 10734 /* Non-probe-rtt case and reduced probe-rtt */ 10735 if ((bbr->rc_bbr_state == BBR_STATE_PROBE_BW) && 10736 (bbr->r_ctl.rc_bbr_hptsi_gain > BBR_UNIT)) { 10737 /* For gain cycle we use the hptsi gain */ 10738 tar = bbr_get_a_state_target(bbr, bbr->r_ctl.rc_bbr_hptsi_gain); 10739 meth = 2; 10740 } else if ((bbr_target_is_bbunit) || bbr->rc_use_google) { 10741 /* 10742 * If configured, or for google all other states 10743 * get BBR_UNIT. 10744 */ 10745 tar = bbr_get_a_state_target(bbr, BBR_UNIT); 10746 meth = 3; 10747 } else { 10748 /* 10749 * Or we set a target based on the pacing gain 10750 * for non-google mode and default (non-configured). 10751 * Note we don't set a target goal below drain (192). 10752 */ 10753 if (bbr->r_ctl.rc_bbr_hptsi_gain < bbr_hptsi_gain[BBR_SUB_DRAIN]) { 10754 tar = bbr_get_a_state_target(bbr, bbr_hptsi_gain[BBR_SUB_DRAIN]); 10755 meth = 4; 10756 } else { 10757 tar = bbr_get_a_state_target(bbr, bbr->r_ctl.rc_bbr_hptsi_gain); 10758 meth = 5; 10759 } 10760 } 10761 } 10762 bbr_log_set_of_state_target(bbr, tar, line, meth); 10763 bbr->r_ctl.rc_target_at_state = tar; 10764 } 10765 10766 static void 10767 bbr_enter_probe_rtt(struct tcp_bbr *bbr, uint32_t cts, int32_t line) 10768 { 10769 /* Change to probe_rtt */ 10770 uint32_t time_in; 10771 10772 bbr->r_ctl.bbr_lost_at_state = bbr->r_ctl.rc_lost; 10773 bbr->r_ctl.flightsize_at_drain = ctf_flight_size(bbr->rc_tp, 10774 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 10775 bbr->r_ctl.r_app_limited_until = (bbr->r_ctl.flightsize_at_drain 10776 + bbr->r_ctl.rc_delivered); 10777 /* Setup so we force feed the filter */ 10778 if (bbr->rc_use_google || bbr_probertt_sets_rtt) 10779 bbr->rc_prtt_set_ts = 1; 10780 if (SEQ_GT(cts, bbr->r_ctl.rc_bbr_state_time)) { 10781 time_in = cts - bbr->r_ctl.rc_bbr_state_time; 10782 counter_u64_add(bbr_state_time[bbr->rc_bbr_state], time_in); 10783 } 10784 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_ENTERPROBE, 0); 10785 bbr->r_ctl.rc_rtt_shrinks = cts; 10786 bbr->r_ctl.last_in_probertt = cts; 10787 bbr->r_ctl.rc_probertt_srttchktim = cts; 10788 bbr->r_ctl.rc_bbr_state_time = cts; 10789 bbr->rc_bbr_state = BBR_STATE_PROBE_RTT; 10790 /* We need to force the filter to update */ 10791 10792 if ((bbr_sub_drain_slam_cwnd) && 10793 bbr->rc_hit_state_1 && 10794 (bbr->rc_use_google == 0) && 10795 (bbr_state_val(bbr) == BBR_SUB_DRAIN)) { 10796 if (bbr->rc_tp->snd_cwnd > bbr->r_ctl.rc_saved_cwnd) 10797 bbr->r_ctl.rc_saved_cwnd = bbr->rc_tp->snd_cwnd; 10798 } else 10799 bbr->r_ctl.rc_saved_cwnd = bbr->rc_tp->snd_cwnd; 10800 /* Update the lost */ 10801 bbr->r_ctl.rc_lost_at_startup = bbr->r_ctl.rc_lost; 10802 if ((bbr->r_ctl.bbr_rttprobe_gain_val == 0) || bbr->rc_use_google){ 10803 /* Set to the non-configurable default of 4 (PROBE_RTT_MIN) */ 10804 bbr->rc_tp->snd_cwnd = bbr_rtt_probe_cwndtarg * (bbr->rc_tp->t_maxseg - bbr->rc_last_options); 10805 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 10806 bbr->r_ctl.rc_bbr_hptsi_gain = BBR_UNIT; 10807 bbr->r_ctl.rc_bbr_cwnd_gain = BBR_UNIT; 10808 bbr_log_set_of_state_target(bbr, bbr->rc_tp->snd_cwnd, __LINE__, 6); 10809 bbr->r_ctl.rc_target_at_state = bbr->rc_tp->snd_cwnd; 10810 } else { 10811 /* 10812 * We bring it down slowly by using a hptsi gain that is 10813 * probably 75%. This will slowly float down our outstanding 10814 * without tampering with the cwnd. 10815 */ 10816 bbr->r_ctl.rc_bbr_hptsi_gain = bbr->r_ctl.bbr_rttprobe_gain_val; 10817 bbr->r_ctl.rc_bbr_cwnd_gain = BBR_UNIT; 10818 bbr_set_state_target(bbr, __LINE__); 10819 if (bbr_prtt_slam_cwnd && 10820 (bbr->rc_tp->snd_cwnd > bbr->r_ctl.rc_target_at_state)) { 10821 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_target_at_state; 10822 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 10823 } 10824 } 10825 if (ctf_flight_size(bbr->rc_tp, 10826 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)) <= 10827 bbr->r_ctl.rc_target_at_state) { 10828 /* We are at target */ 10829 bbr->r_ctl.rc_bbr_enters_probertt = cts; 10830 } else { 10831 /* We need to come down to reach target before our time begins */ 10832 bbr->r_ctl.rc_bbr_enters_probertt = 0; 10833 } 10834 bbr->r_ctl.rc_pe_of_prtt = bbr->r_ctl.rc_pkt_epoch; 10835 BBR_STAT_INC(bbr_enter_probertt); 10836 bbr_log_exit_gain(bbr, cts, 0); 10837 bbr_log_type_statechange(bbr, cts, line); 10838 } 10839 10840 static void 10841 bbr_check_probe_rtt_limits(struct tcp_bbr *bbr, uint32_t cts) 10842 { 10843 /* 10844 * Sanity check on probe-rtt intervals. 10845 * In crazy situations where we are competing 10846 * against new-reno flows with huge buffers 10847 * our rtt-prop interval could come to dominate 10848 * things if we can't get through a full set 10849 * of cycles, we need to adjust it. 10850 */ 10851 if (bbr_can_adjust_probertt && 10852 (bbr->rc_use_google == 0)) { 10853 uint16_t val = 0; 10854 uint32_t cur_rttp, fval, newval, baseval; 10855 10856 /* Are we to small and go into probe-rtt to often? */ 10857 baseval = (bbr_get_rtt(bbr, BBR_RTT_PROP) * (BBR_SUBSTATE_COUNT + 1)); 10858 cur_rttp = roundup(baseval, USECS_IN_SECOND); 10859 fval = bbr_filter_len_sec * USECS_IN_SECOND; 10860 if (bbr_is_ratio == 0) { 10861 if (fval > bbr_rtt_probe_limit) 10862 newval = cur_rttp + (fval - bbr_rtt_probe_limit); 10863 else 10864 newval = cur_rttp; 10865 } else { 10866 int mul; 10867 10868 mul = fval / bbr_rtt_probe_limit; 10869 newval = cur_rttp * mul; 10870 } 10871 if (cur_rttp > bbr->r_ctl.rc_probertt_int) { 10872 bbr->r_ctl.rc_probertt_int = cur_rttp; 10873 reset_time_small(&bbr->r_ctl.rc_rttprop, newval); 10874 val = 1; 10875 } else { 10876 /* 10877 * No adjustments were made 10878 * do we need to shrink it? 10879 */ 10880 if (bbr->r_ctl.rc_probertt_int > bbr_rtt_probe_limit) { 10881 if (cur_rttp <= bbr_rtt_probe_limit) { 10882 /* 10883 * Things have calmed down lets 10884 * shrink all the way to default 10885 */ 10886 bbr->r_ctl.rc_probertt_int = bbr_rtt_probe_limit; 10887 reset_time_small(&bbr->r_ctl.rc_rttprop, 10888 (bbr_filter_len_sec * USECS_IN_SECOND)); 10889 cur_rttp = bbr_rtt_probe_limit; 10890 newval = (bbr_filter_len_sec * USECS_IN_SECOND); 10891 val = 2; 10892 } else { 10893 /* 10894 * Well does some adjustment make sense? 10895 */ 10896 if (cur_rttp < bbr->r_ctl.rc_probertt_int) { 10897 /* We can reduce interval time some */ 10898 bbr->r_ctl.rc_probertt_int = cur_rttp; 10899 reset_time_small(&bbr->r_ctl.rc_rttprop, newval); 10900 val = 3; 10901 } 10902 } 10903 } 10904 } 10905 if (val) 10906 bbr_log_rtt_shrinks(bbr, cts, cur_rttp, newval, __LINE__, BBR_RTTS_RESETS_VALUES, val); 10907 } 10908 } 10909 10910 static void 10911 bbr_exit_probe_rtt(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts) 10912 { 10913 /* Exit probe-rtt */ 10914 10915 if (tp->snd_cwnd < bbr->r_ctl.rc_saved_cwnd) { 10916 tp->snd_cwnd = bbr->r_ctl.rc_saved_cwnd; 10917 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 10918 } 10919 bbr_log_exit_gain(bbr, cts, 1); 10920 bbr->rc_hit_state_1 = 0; 10921 bbr->r_ctl.rc_rtt_shrinks = cts; 10922 bbr->r_ctl.last_in_probertt = cts; 10923 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_RTTPROBE, 0); 10924 bbr->r_ctl.bbr_lost_at_state = bbr->r_ctl.rc_lost; 10925 bbr->r_ctl.r_app_limited_until = (ctf_flight_size(tp, 10926 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)) + 10927 bbr->r_ctl.rc_delivered); 10928 if (SEQ_GT(cts, bbr->r_ctl.rc_bbr_state_time)) { 10929 uint32_t time_in; 10930 10931 time_in = cts - bbr->r_ctl.rc_bbr_state_time; 10932 counter_u64_add(bbr_state_time[bbr->rc_bbr_state], time_in); 10933 } 10934 if (bbr->rc_filled_pipe) { 10935 /* Switch to probe_bw */ 10936 bbr->rc_bbr_state = BBR_STATE_PROBE_BW; 10937 bbr->rc_bbr_substate = bbr_pick_probebw_substate(bbr, cts); 10938 bbr->r_ctl.rc_bbr_cwnd_gain = bbr_cwnd_gain; 10939 bbr_substate_change(bbr, cts, __LINE__, 0); 10940 bbr_log_type_statechange(bbr, cts, __LINE__); 10941 } else { 10942 /* Back to startup */ 10943 bbr->rc_bbr_state = BBR_STATE_STARTUP; 10944 bbr->r_ctl.rc_bbr_state_time = cts; 10945 /* 10946 * We don't want to give a complete free 3 10947 * measurements until we exit, so we use 10948 * the number of pe's we were in probe-rtt 10949 * to add to the startup_epoch. That way 10950 * we will still retain the old state. 10951 */ 10952 bbr->r_ctl.rc_bbr_last_startup_epoch += (bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_pe_of_prtt); 10953 bbr->r_ctl.rc_lost_at_startup = bbr->r_ctl.rc_lost; 10954 /* Make sure to use the lower pg when shifting back in */ 10955 if (bbr->r_ctl.rc_lost && 10956 bbr_use_lower_gain_in_startup && 10957 (bbr->rc_use_google == 0)) 10958 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_startup_lower; 10959 else 10960 bbr->r_ctl.rc_bbr_hptsi_gain = bbr->r_ctl.rc_startup_pg; 10961 bbr->r_ctl.rc_bbr_cwnd_gain = bbr->r_ctl.rc_startup_pg; 10962 /* Probably not needed but set it anyway */ 10963 bbr_set_state_target(bbr, __LINE__); 10964 bbr_log_type_statechange(bbr, cts, __LINE__); 10965 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch, 10966 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 0); 10967 } 10968 bbr_check_probe_rtt_limits(bbr, cts); 10969 } 10970 10971 static int32_t inline 10972 bbr_should_enter_probe_rtt(struct tcp_bbr *bbr, uint32_t cts) 10973 { 10974 if ((bbr->rc_past_init_win == 1) && 10975 (bbr->rc_in_persist == 0) && 10976 (bbr_calc_time(cts, bbr->r_ctl.rc_rtt_shrinks) >= bbr->r_ctl.rc_probertt_int)) { 10977 return (1); 10978 } 10979 if (bbr_can_force_probertt && 10980 (bbr->rc_in_persist == 0) && 10981 (TSTMP_GT(cts, bbr->r_ctl.last_in_probertt)) && 10982 ((cts - bbr->r_ctl.last_in_probertt) > bbr->r_ctl.rc_probertt_int)) { 10983 return (1); 10984 } 10985 return (0); 10986 } 10987 10988 static int32_t 10989 bbr_google_startup(struct tcp_bbr *bbr, uint32_t cts, int32_t pkt_epoch) 10990 { 10991 uint64_t btlbw, gain; 10992 if (pkt_epoch == 0) { 10993 /* 10994 * Need to be on a pkt-epoch to continue. 10995 */ 10996 return (0); 10997 } 10998 btlbw = bbr_get_full_bw(bbr); 10999 gain = ((bbr->r_ctl.rc_bbr_lastbtlbw * 11000 (uint64_t)bbr_start_exit) / (uint64_t)100) + bbr->r_ctl.rc_bbr_lastbtlbw; 11001 if (btlbw >= gain) { 11002 bbr->r_ctl.rc_bbr_last_startup_epoch = bbr->r_ctl.rc_pkt_epoch; 11003 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch, 11004 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 3); 11005 bbr->r_ctl.rc_bbr_lastbtlbw = btlbw; 11006 } 11007 if ((bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_bbr_last_startup_epoch) >= BBR_STARTUP_EPOCHS) 11008 return (1); 11009 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch, 11010 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 8); 11011 return(0); 11012 } 11013 11014 static int32_t inline 11015 bbr_state_startup(struct tcp_bbr *bbr, uint32_t cts, int32_t epoch, int32_t pkt_epoch) 11016 { 11017 /* Have we gained 25% in the last 3 packet based epoch's? */ 11018 uint64_t btlbw, gain; 11019 int do_exit; 11020 int delta, rtt_gain; 11021 11022 if ((bbr->rc_tp->snd_una == bbr->rc_tp->snd_max) && 11023 (bbr_calc_time(cts, bbr->r_ctl.rc_went_idle_time) >= bbr_rtt_probe_time)) { 11024 /* 11025 * This qualifies as a RTT_PROBE session since we drop the 11026 * data outstanding to nothing and waited more than 11027 * bbr_rtt_probe_time. 11028 */ 11029 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_WASIDLE, 0); 11030 bbr_set_reduced_rtt(bbr, cts, __LINE__); 11031 } 11032 if (bbr_should_enter_probe_rtt(bbr, cts)) { 11033 bbr_enter_probe_rtt(bbr, cts, __LINE__); 11034 return (0); 11035 } 11036 if (bbr->rc_use_google) 11037 return (bbr_google_startup(bbr, cts, pkt_epoch)); 11038 11039 if ((bbr->r_ctl.rc_lost > bbr->r_ctl.rc_lost_at_startup) && 11040 (bbr_use_lower_gain_in_startup)) { 11041 /* Drop to a lower gain 1.5 x since we saw loss */ 11042 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_startup_lower; 11043 } 11044 if (pkt_epoch == 0) { 11045 /* 11046 * Need to be on a pkt-epoch to continue. 11047 */ 11048 return (0); 11049 } 11050 if (bbr_rtt_gain_thresh) { 11051 /* 11052 * Do we allow a flow to stay 11053 * in startup with no loss and no 11054 * gain in rtt over a set threshold? 11055 */ 11056 if (bbr->r_ctl.rc_pkt_epoch_rtt && 11057 bbr->r_ctl.startup_last_srtt && 11058 (bbr->r_ctl.rc_pkt_epoch_rtt > bbr->r_ctl.startup_last_srtt)) { 11059 delta = bbr->r_ctl.rc_pkt_epoch_rtt - bbr->r_ctl.startup_last_srtt; 11060 rtt_gain = (delta * 100) / bbr->r_ctl.startup_last_srtt; 11061 } else 11062 rtt_gain = 0; 11063 if ((bbr->r_ctl.startup_last_srtt == 0) || 11064 (bbr->r_ctl.rc_pkt_epoch_rtt < bbr->r_ctl.startup_last_srtt)) 11065 /* First time or new lower value */ 11066 bbr->r_ctl.startup_last_srtt = bbr->r_ctl.rc_pkt_epoch_rtt; 11067 11068 if ((bbr->r_ctl.rc_lost == 0) && 11069 (rtt_gain < bbr_rtt_gain_thresh)) { 11070 /* 11071 * No loss, and we are under 11072 * our gain threhold for 11073 * increasing RTT. 11074 */ 11075 if (bbr->r_ctl.rc_bbr_last_startup_epoch < bbr->r_ctl.rc_pkt_epoch) 11076 bbr->r_ctl.rc_bbr_last_startup_epoch++; 11077 bbr_log_startup_event(bbr, cts, rtt_gain, 11078 delta, bbr->r_ctl.startup_last_srtt, 10); 11079 return (0); 11080 } 11081 } 11082 if ((bbr->r_ctl.r_measurement_count == bbr->r_ctl.last_startup_measure) && 11083 (bbr->r_ctl.rc_lost_at_startup == bbr->r_ctl.rc_lost) && 11084 (!IN_RECOVERY(bbr->rc_tp->t_flags))) { 11085 /* 11086 * We only assess if we have a new measurment when 11087 * we have no loss and are not in recovery. 11088 * Drag up by one our last_startup epoch so we will hold 11089 * the number of non-gain we have already accumulated. 11090 */ 11091 if (bbr->r_ctl.rc_bbr_last_startup_epoch < bbr->r_ctl.rc_pkt_epoch) 11092 bbr->r_ctl.rc_bbr_last_startup_epoch++; 11093 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch, 11094 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 9); 11095 return (0); 11096 } 11097 /* Case where we reduced the lost (bad retransmit) */ 11098 if (bbr->r_ctl.rc_lost_at_startup > bbr->r_ctl.rc_lost) 11099 bbr->r_ctl.rc_lost_at_startup = bbr->r_ctl.rc_lost; 11100 bbr->r_ctl.last_startup_measure = bbr->r_ctl.r_measurement_count; 11101 btlbw = bbr_get_full_bw(bbr); 11102 if (bbr->r_ctl.rc_bbr_hptsi_gain == bbr_startup_lower) 11103 gain = ((bbr->r_ctl.rc_bbr_lastbtlbw * 11104 (uint64_t)bbr_low_start_exit) / (uint64_t)100) + bbr->r_ctl.rc_bbr_lastbtlbw; 11105 else 11106 gain = ((bbr->r_ctl.rc_bbr_lastbtlbw * 11107 (uint64_t)bbr_start_exit) / (uint64_t)100) + bbr->r_ctl.rc_bbr_lastbtlbw; 11108 do_exit = 0; 11109 if (btlbw > bbr->r_ctl.rc_bbr_lastbtlbw) 11110 bbr->r_ctl.rc_bbr_lastbtlbw = btlbw; 11111 if (btlbw >= gain) { 11112 bbr->r_ctl.rc_bbr_last_startup_epoch = bbr->r_ctl.rc_pkt_epoch; 11113 /* Update the lost so we won't exit in next set of tests */ 11114 bbr->r_ctl.rc_lost_at_startup = bbr->r_ctl.rc_lost; 11115 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch, 11116 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 3); 11117 } 11118 if ((bbr->rc_loss_exit && 11119 (bbr->r_ctl.rc_lost > bbr->r_ctl.rc_lost_at_startup) && 11120 (bbr->r_ctl.rc_pkt_epoch_loss_rate > bbr_startup_loss_thresh)) && 11121 ((bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_bbr_last_startup_epoch) >= BBR_STARTUP_EPOCHS)) { 11122 /* 11123 * If we had no gain, we had loss and that loss was above 11124 * our threshould, the rwnd is not constrained, and we have 11125 * had at least 3 packet epochs exit. Note that this is 11126 * switched off by sysctl. Google does not do this by the 11127 * way. 11128 */ 11129 if ((ctf_flight_size(bbr->rc_tp, 11130 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)) + 11131 (2 * max(bbr->r_ctl.rc_pace_max_segs, bbr->rc_tp->t_maxseg))) <= bbr->rc_tp->snd_wnd) { 11132 do_exit = 1; 11133 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch, 11134 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 4); 11135 } else { 11136 /* Just record an updated loss value */ 11137 bbr->r_ctl.rc_lost_at_startup = bbr->r_ctl.rc_lost; 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, 5); 11140 } 11141 } else 11142 bbr->r_ctl.rc_lost_at_startup = bbr->r_ctl.rc_lost; 11143 if (((bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_bbr_last_startup_epoch) >= BBR_STARTUP_EPOCHS) || 11144 do_exit) { 11145 /* Return 1 to exit the startup state. */ 11146 return (1); 11147 } 11148 /* Stay in startup */ 11149 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch, 11150 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 8); 11151 return (0); 11152 } 11153 11154 static void 11155 bbr_state_change(struct tcp_bbr *bbr, uint32_t cts, int32_t epoch, int32_t pkt_epoch, uint32_t losses) 11156 { 11157 /* 11158 * A tick occured in the rtt epoch do we need to do anything? 11159 */ 11160 #ifdef BBR_INVARIANTS 11161 if ((bbr->rc_bbr_state != BBR_STATE_STARTUP) && 11162 (bbr->rc_bbr_state != BBR_STATE_DRAIN) && 11163 (bbr->rc_bbr_state != BBR_STATE_PROBE_RTT) && 11164 (bbr->rc_bbr_state != BBR_STATE_IDLE_EXIT) && 11165 (bbr->rc_bbr_state != BBR_STATE_PROBE_BW)) { 11166 /* Debug code? */ 11167 panic("Unknown BBR state %d?\n", bbr->rc_bbr_state); 11168 } 11169 #endif 11170 if (bbr->rc_bbr_state == BBR_STATE_STARTUP) { 11171 /* Do we exit the startup state? */ 11172 if (bbr_state_startup(bbr, cts, epoch, pkt_epoch)) { 11173 uint32_t time_in; 11174 11175 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch, 11176 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 6); 11177 bbr->rc_filled_pipe = 1; 11178 bbr->r_ctl.bbr_lost_at_state = bbr->r_ctl.rc_lost; 11179 if (SEQ_GT(cts, bbr->r_ctl.rc_bbr_state_time)) { 11180 time_in = cts - bbr->r_ctl.rc_bbr_state_time; 11181 counter_u64_add(bbr_state_time[bbr->rc_bbr_state], time_in); 11182 } else 11183 time_in = 0; 11184 if (bbr->rc_no_pacing) 11185 bbr->rc_no_pacing = 0; 11186 bbr->r_ctl.rc_bbr_state_time = cts; 11187 bbr->r_ctl.rc_bbr_hptsi_gain = bbr->r_ctl.rc_drain_pg; 11188 bbr->rc_bbr_state = BBR_STATE_DRAIN; 11189 bbr_set_state_target(bbr, __LINE__); 11190 if ((bbr->rc_use_google == 0) && 11191 bbr_slam_cwnd_in_main_drain) { 11192 /* Here we don't have to worry about probe-rtt */ 11193 bbr->r_ctl.rc_saved_cwnd = bbr->rc_tp->snd_cwnd; 11194 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_target_at_state; 11195 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 11196 } 11197 bbr->r_ctl.rc_bbr_cwnd_gain = bbr_high_gain; 11198 bbr_log_type_statechange(bbr, cts, __LINE__); 11199 if (ctf_flight_size(bbr->rc_tp, 11200 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)) <= 11201 bbr->r_ctl.rc_target_at_state) { 11202 /* 11203 * Switch to probe_bw if we are already 11204 * there 11205 */ 11206 bbr->rc_bbr_substate = bbr_pick_probebw_substate(bbr, cts); 11207 bbr_substate_change(bbr, cts, __LINE__, 0); 11208 bbr->rc_bbr_state = BBR_STATE_PROBE_BW; 11209 bbr_log_type_statechange(bbr, cts, __LINE__); 11210 } 11211 } 11212 } else if (bbr->rc_bbr_state == BBR_STATE_IDLE_EXIT) { 11213 uint32_t inflight; 11214 struct tcpcb *tp; 11215 11216 tp = bbr->rc_tp; 11217 inflight = ctf_flight_size(tp, 11218 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 11219 if (inflight >= bbr->r_ctl.rc_target_at_state) { 11220 /* We have reached a flight of the cwnd target */ 11221 bbr->rc_bbr_state = BBR_STATE_PROBE_BW; 11222 bbr->r_ctl.rc_bbr_hptsi_gain = BBR_UNIT; 11223 bbr->r_ctl.rc_bbr_cwnd_gain = BBR_UNIT; 11224 bbr_set_state_target(bbr, __LINE__); 11225 /* 11226 * Rig it so we don't do anything crazy and 11227 * start fresh with a new randomization. 11228 */ 11229 bbr->r_ctl.bbr_smallest_srtt_this_state = 0xffffffff; 11230 bbr->rc_bbr_substate = BBR_SUB_LEVEL6; 11231 bbr_substate_change(bbr, cts, __LINE__, 1); 11232 } 11233 } else if (bbr->rc_bbr_state == BBR_STATE_DRAIN) { 11234 /* Has in-flight reached the bdp (or less)? */ 11235 uint32_t inflight; 11236 struct tcpcb *tp; 11237 11238 tp = bbr->rc_tp; 11239 inflight = ctf_flight_size(tp, 11240 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 11241 if ((bbr->rc_use_google == 0) && 11242 bbr_slam_cwnd_in_main_drain && 11243 (bbr->rc_tp->snd_cwnd > bbr->r_ctl.rc_target_at_state)) { 11244 /* 11245 * Here we don't have to worry about probe-rtt 11246 * re-slam it, but keep it slammed down. 11247 */ 11248 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_target_at_state; 11249 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 11250 } 11251 if (inflight <= bbr->r_ctl.rc_target_at_state) { 11252 /* We have drained */ 11253 bbr->rc_bbr_state = BBR_STATE_PROBE_BW; 11254 bbr->r_ctl.bbr_lost_at_state = bbr->r_ctl.rc_lost; 11255 if (SEQ_GT(cts, bbr->r_ctl.rc_bbr_state_time)) { 11256 uint32_t time_in; 11257 11258 time_in = cts - bbr->r_ctl.rc_bbr_state_time; 11259 counter_u64_add(bbr_state_time[bbr->rc_bbr_state], time_in); 11260 } 11261 if ((bbr->rc_use_google == 0) && 11262 bbr_slam_cwnd_in_main_drain && 11263 (tp->snd_cwnd < bbr->r_ctl.rc_saved_cwnd)) { 11264 /* Restore the cwnd */ 11265 tp->snd_cwnd = bbr->r_ctl.rc_saved_cwnd; 11266 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 11267 } 11268 /* Setup probe-rtt has being done now RRS-HERE */ 11269 bbr->r_ctl.rc_rtt_shrinks = cts; 11270 bbr->r_ctl.last_in_probertt = cts; 11271 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_LEAVE_DRAIN, 0); 11272 /* Randomly pick a sub-state */ 11273 bbr->rc_bbr_substate = bbr_pick_probebw_substate(bbr, cts); 11274 bbr_substate_change(bbr, cts, __LINE__, 0); 11275 bbr_log_type_statechange(bbr, cts, __LINE__); 11276 } 11277 } else if (bbr->rc_bbr_state == BBR_STATE_PROBE_RTT) { 11278 uint32_t flight; 11279 11280 flight = ctf_flight_size(bbr->rc_tp, 11281 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 11282 bbr->r_ctl.r_app_limited_until = (flight + bbr->r_ctl.rc_delivered); 11283 if (((bbr->r_ctl.bbr_rttprobe_gain_val == 0) || bbr->rc_use_google) && 11284 (bbr->rc_tp->snd_cwnd > bbr->r_ctl.rc_target_at_state)) { 11285 /* 11286 * We must keep cwnd at the desired MSS. 11287 */ 11288 bbr->rc_tp->snd_cwnd = bbr_rtt_probe_cwndtarg * (bbr->rc_tp->t_maxseg - bbr->rc_last_options); 11289 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 11290 } else if ((bbr_prtt_slam_cwnd) && 11291 (bbr->rc_tp->snd_cwnd > bbr->r_ctl.rc_target_at_state)) { 11292 /* Re-slam it */ 11293 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_target_at_state; 11294 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__); 11295 } 11296 if (bbr->r_ctl.rc_bbr_enters_probertt == 0) { 11297 /* Has outstanding reached our target? */ 11298 if (flight <= bbr->r_ctl.rc_target_at_state) { 11299 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_REACHTAR, 0); 11300 bbr->r_ctl.rc_bbr_enters_probertt = cts; 11301 /* If time is exactly 0, be 1usec off */ 11302 if (bbr->r_ctl.rc_bbr_enters_probertt == 0) 11303 bbr->r_ctl.rc_bbr_enters_probertt = 1; 11304 if (bbr->rc_use_google == 0) { 11305 /* 11306 * Restore any lowering that as occured to 11307 * reach here 11308 */ 11309 if (bbr->r_ctl.bbr_rttprobe_gain_val) 11310 bbr->r_ctl.rc_bbr_hptsi_gain = bbr->r_ctl.bbr_rttprobe_gain_val; 11311 else 11312 bbr->r_ctl.rc_bbr_hptsi_gain = BBR_UNIT; 11313 } 11314 } 11315 if ((bbr->r_ctl.rc_bbr_enters_probertt == 0) && 11316 (bbr->rc_use_google == 0) && 11317 bbr->r_ctl.bbr_rttprobe_gain_val && 11318 (((cts - bbr->r_ctl.rc_probertt_srttchktim) > bbr_get_rtt(bbr, bbr_drain_rtt)) || 11319 (flight >= bbr->r_ctl.flightsize_at_drain))) { 11320 /* 11321 * We have doddled with our current hptsi 11322 * gain an srtt and have still not made it 11323 * to target, or we have increased our flight. 11324 * Lets reduce the gain by xx% 11325 * flooring the reduce at DRAIN (based on 11326 * mul/div) 11327 */ 11328 int red; 11329 11330 bbr->r_ctl.flightsize_at_drain = flight; 11331 bbr->r_ctl.rc_probertt_srttchktim = cts; 11332 red = max((bbr->r_ctl.bbr_rttprobe_gain_val / 10), 1); 11333 if ((bbr->r_ctl.rc_bbr_hptsi_gain - red) > max(bbr_drain_floor, 1)) { 11334 /* Reduce our gain again */ 11335 bbr->r_ctl.rc_bbr_hptsi_gain -= red; 11336 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_SHRINK_PG, 0); 11337 } else if (bbr->r_ctl.rc_bbr_hptsi_gain > max(bbr_drain_floor, 1)) { 11338 /* one more chance before we give up */ 11339 bbr->r_ctl.rc_bbr_hptsi_gain = max(bbr_drain_floor, 1); 11340 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_SHRINK_PG_FINAL, 0); 11341 } else { 11342 /* At the very bottom */ 11343 bbr->r_ctl.rc_bbr_hptsi_gain = max((bbr_drain_floor-1), 1); 11344 } 11345 } 11346 } 11347 if (bbr->r_ctl.rc_bbr_enters_probertt && 11348 (TSTMP_GT(cts, bbr->r_ctl.rc_bbr_enters_probertt)) && 11349 ((cts - bbr->r_ctl.rc_bbr_enters_probertt) >= bbr_rtt_probe_time)) { 11350 /* Time to exit probe RTT normally */ 11351 bbr_exit_probe_rtt(bbr->rc_tp, bbr, cts); 11352 } 11353 } else if (bbr->rc_bbr_state == BBR_STATE_PROBE_BW) { 11354 if ((bbr->rc_tp->snd_una == bbr->rc_tp->snd_max) && 11355 (bbr_calc_time(cts, bbr->r_ctl.rc_went_idle_time) >= bbr_rtt_probe_time)) { 11356 /* 11357 * This qualifies as a RTT_PROBE session since we 11358 * drop the data outstanding to nothing and waited 11359 * more than bbr_rtt_probe_time. 11360 */ 11361 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_WASIDLE, 0); 11362 bbr_set_reduced_rtt(bbr, cts, __LINE__); 11363 } 11364 if (bbr_should_enter_probe_rtt(bbr, cts)) { 11365 bbr_enter_probe_rtt(bbr, cts, __LINE__); 11366 } else { 11367 bbr_set_probebw_gains(bbr, cts, losses); 11368 } 11369 } 11370 } 11371 11372 static void 11373 bbr_check_bbr_for_state(struct tcp_bbr *bbr, uint32_t cts, int32_t line, uint32_t losses) 11374 { 11375 int32_t epoch = 0; 11376 11377 if ((cts - bbr->r_ctl.rc_rcv_epoch_start) >= bbr_get_rtt(bbr, BBR_RTT_PROP)) { 11378 bbr_set_epoch(bbr, cts, line); 11379 /* At each epoch doe lt bw sampling */ 11380 epoch = 1; 11381 } 11382 bbr_state_change(bbr, cts, epoch, bbr->rc_is_pkt_epoch_now, losses); 11383 } 11384 11385 static int 11386 bbr_do_segment_nounlock(struct mbuf *m, struct tcphdr *th, struct socket *so, 11387 struct tcpcb *tp, int32_t drop_hdrlen, int32_t tlen, uint8_t iptos, 11388 int32_t nxt_pkt, struct timeval *tv) 11389 { 11390 int32_t thflags, retval; 11391 uint32_t cts, lcts; 11392 uint32_t tiwin; 11393 struct tcpopt to; 11394 struct tcp_bbr *bbr; 11395 struct bbr_sendmap *rsm; 11396 struct timeval ltv; 11397 int32_t did_out = 0; 11398 int32_t in_recovery; 11399 uint16_t nsegs; 11400 int32_t prev_state; 11401 uint32_t lost; 11402 11403 nsegs = max(1, m->m_pkthdr.lro_nsegs); 11404 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 11405 /* add in our stats */ 11406 kern_prefetch(bbr, &prev_state); 11407 prev_state = 0; 11408 thflags = th->th_flags; 11409 /* 11410 * If this is either a state-changing packet or current state isn't 11411 * established, we require a write lock on tcbinfo. Otherwise, we 11412 * allow the tcbinfo to be in either alocked or unlocked, as the 11413 * caller may have unnecessarily acquired a write lock due to a 11414 * race. 11415 */ 11416 INP_WLOCK_ASSERT(tp->t_inpcb); 11417 KASSERT(tp->t_state > TCPS_LISTEN, ("%s: TCPS_LISTEN", 11418 __func__)); 11419 KASSERT(tp->t_state != TCPS_TIME_WAIT, ("%s: TCPS_TIME_WAIT", 11420 __func__)); 11421 11422 tp->t_rcvtime = ticks; 11423 /* 11424 * Unscale the window into a 32-bit value. For the SYN_SENT state 11425 * the scale is zero. 11426 */ 11427 tiwin = th->th_win << tp->snd_scale; 11428 #ifdef STATS 11429 stats_voi_update_abs_ulong(tp->t_stats, VOI_TCP_FRWIN, tiwin); 11430 #endif 11431 /* 11432 * Parse options on any incoming segment. 11433 */ 11434 tcp_dooptions(&to, (u_char *)(th + 1), 11435 (th->th_off << 2) - sizeof(struct tcphdr), 11436 (thflags & TH_SYN) ? TO_SYN : 0); 11437 11438 if (m->m_flags & M_TSTMP) { 11439 /* Prefer the hardware timestamp if present */ 11440 struct timespec ts; 11441 11442 mbuf_tstmp2timespec(m, &ts); 11443 bbr->rc_tv.tv_sec = ts.tv_sec; 11444 bbr->rc_tv.tv_usec = ts.tv_nsec / 1000; 11445 bbr->r_ctl.rc_rcvtime = cts = tcp_tv_to_usectick(&bbr->rc_tv); 11446 } else if (m->m_flags & M_TSTMP_LRO) { 11447 /* Next the arrival timestamp */ 11448 struct timespec ts; 11449 11450 mbuf_tstmp2timespec(m, &ts); 11451 bbr->rc_tv.tv_sec = ts.tv_sec; 11452 bbr->rc_tv.tv_usec = ts.tv_nsec / 1000; 11453 bbr->r_ctl.rc_rcvtime = cts = tcp_tv_to_usectick(&bbr->rc_tv); 11454 } else { 11455 /* 11456 * Ok just get the current time. 11457 */ 11458 bbr->r_ctl.rc_rcvtime = lcts = cts = tcp_get_usecs(&bbr->rc_tv); 11459 } 11460 /* 11461 * If echoed timestamp is later than the current time, fall back to 11462 * non RFC1323 RTT calculation. Normalize timestamp if syncookies 11463 * were used when this connection was established. 11464 */ 11465 if ((to.to_flags & TOF_TS) && (to.to_tsecr != 0)) { 11466 to.to_tsecr -= tp->ts_offset; 11467 if (TSTMP_GT(to.to_tsecr, tcp_tv_to_mssectick(&bbr->rc_tv))) 11468 to.to_tsecr = 0; 11469 } 11470 /* 11471 * If its the first time in we need to take care of options and 11472 * verify we can do SACK for rack! 11473 */ 11474 if (bbr->r_state == 0) { 11475 /* 11476 * Process options only when we get SYN/ACK back. The SYN 11477 * case for incoming connections is handled in tcp_syncache. 11478 * According to RFC1323 the window field in a SYN (i.e., a 11479 * <SYN> or <SYN,ACK>) segment itself is never scaled. XXX 11480 * this is traditional behavior, may need to be cleaned up. 11481 */ 11482 if (bbr->rc_inp == NULL) { 11483 bbr->rc_inp = tp->t_inpcb; 11484 } 11485 /* 11486 * We need to init rc_inp here since its not init'd when 11487 * bbr_init is called 11488 */ 11489 if (tp->t_state == TCPS_SYN_SENT && (thflags & TH_SYN)) { 11490 if ((to.to_flags & TOF_SCALE) && 11491 (tp->t_flags & TF_REQ_SCALE)) { 11492 tp->t_flags |= TF_RCVD_SCALE; 11493 tp->snd_scale = to.to_wscale; 11494 } else 11495 tp->t_flags &= ~TF_REQ_SCALE; 11496 /* 11497 * Initial send window. It will be updated with the 11498 * next incoming segment to the scaled value. 11499 */ 11500 tp->snd_wnd = th->th_win; 11501 if ((to.to_flags & TOF_TS) && 11502 (tp->t_flags & TF_REQ_TSTMP)) { 11503 tp->t_flags |= TF_RCVD_TSTMP; 11504 tp->ts_recent = to.to_tsval; 11505 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv); 11506 } else 11507 tp->t_flags &= ~TF_REQ_TSTMP; 11508 if (to.to_flags & TOF_MSS) 11509 tcp_mss(tp, to.to_mss); 11510 if ((tp->t_flags & TF_SACK_PERMIT) && 11511 (to.to_flags & TOF_SACKPERM) == 0) 11512 tp->t_flags &= ~TF_SACK_PERMIT; 11513 if (IS_FASTOPEN(tp->t_flags)) { 11514 if (to.to_flags & TOF_FASTOPEN) { 11515 uint16_t mss; 11516 11517 if (to.to_flags & TOF_MSS) 11518 mss = to.to_mss; 11519 else 11520 if ((tp->t_inpcb->inp_vflag & INP_IPV6) != 0) 11521 mss = TCP6_MSS; 11522 else 11523 mss = TCP_MSS; 11524 tcp_fastopen_update_cache(tp, mss, 11525 to.to_tfo_len, to.to_tfo_cookie); 11526 } else 11527 tcp_fastopen_disable_path(tp); 11528 } 11529 } 11530 /* 11531 * At this point we are at the initial call. Here we decide 11532 * if we are doing RACK or not. We do this by seeing if 11533 * TF_SACK_PERMIT is set, if not rack is *not* possible and 11534 * we switch to the default code. 11535 */ 11536 if ((tp->t_flags & TF_SACK_PERMIT) == 0) { 11537 /* Bail */ 11538 tcp_switch_back_to_default(tp); 11539 (*tp->t_fb->tfb_tcp_do_segment) (m, th, so, tp, drop_hdrlen, 11540 tlen, iptos); 11541 return (1); 11542 } 11543 /* Set the flag */ 11544 bbr->r_is_v6 = (tp->t_inpcb->inp_vflag & INP_IPV6) != 0; 11545 tcp_set_hpts(tp->t_inpcb); 11546 sack_filter_clear(&bbr->r_ctl.bbr_sf, th->th_ack); 11547 } 11548 if (thflags & TH_ACK) { 11549 /* Track ack types */ 11550 if (to.to_flags & TOF_SACK) 11551 BBR_STAT_INC(bbr_acks_with_sacks); 11552 else 11553 BBR_STAT_INC(bbr_plain_acks); 11554 } 11555 /* 11556 * This is the one exception case where we set the rack state 11557 * always. All other times (timers etc) we must have a rack-state 11558 * set (so we assure we have done the checks above for SACK). 11559 */ 11560 if (thflags & TH_FIN) 11561 tcp_log_end_status(tp, TCP_EI_STATUS_CLIENT_FIN); 11562 if (bbr->r_state != tp->t_state) 11563 bbr_set_state(tp, bbr, tiwin); 11564 11565 if (SEQ_GT(th->th_ack, tp->snd_una) && (rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map)) != NULL) 11566 kern_prefetch(rsm, &prev_state); 11567 prev_state = bbr->r_state; 11568 bbr->rc_ack_was_delayed = 0; 11569 lost = bbr->r_ctl.rc_lost; 11570 bbr->rc_is_pkt_epoch_now = 0; 11571 if (m->m_flags & (M_TSTMP|M_TSTMP_LRO)) { 11572 /* Get the real time into lcts and figure the real delay */ 11573 lcts = tcp_get_usecs(<v); 11574 if (TSTMP_GT(lcts, cts)) { 11575 bbr->r_ctl.rc_ack_hdwr_delay = lcts - cts; 11576 bbr->rc_ack_was_delayed = 1; 11577 if (TSTMP_GT(bbr->r_ctl.rc_ack_hdwr_delay, 11578 bbr->r_ctl.highest_hdwr_delay)) 11579 bbr->r_ctl.highest_hdwr_delay = bbr->r_ctl.rc_ack_hdwr_delay; 11580 } else { 11581 bbr->r_ctl.rc_ack_hdwr_delay = 0; 11582 bbr->rc_ack_was_delayed = 0; 11583 } 11584 } else { 11585 bbr->r_ctl.rc_ack_hdwr_delay = 0; 11586 bbr->rc_ack_was_delayed = 0; 11587 } 11588 bbr_log_ack_event(bbr, th, &to, tlen, nsegs, cts, nxt_pkt, m); 11589 if ((thflags & TH_SYN) && (thflags & TH_FIN) && V_drop_synfin) { 11590 retval = 0; 11591 m_freem(m); 11592 goto done_with_input; 11593 } 11594 /* 11595 * If a segment with the ACK-bit set arrives in the SYN-SENT state 11596 * check SEQ.ACK first as described on page 66 of RFC 793, section 3.9. 11597 */ 11598 if ((tp->t_state == TCPS_SYN_SENT) && (thflags & TH_ACK) && 11599 (SEQ_LEQ(th->th_ack, tp->iss) || SEQ_GT(th->th_ack, tp->snd_max))) { 11600 tcp_log_end_status(tp, TCP_EI_STATUS_RST_IN_FRONT); 11601 ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen); 11602 return (1); 11603 } 11604 in_recovery = IN_RECOVERY(tp->t_flags); 11605 if (tiwin > bbr->r_ctl.rc_high_rwnd) 11606 bbr->r_ctl.rc_high_rwnd = tiwin; 11607 #ifdef BBR_INVARIANTS 11608 if ((tp->t_inpcb->inp_flags & INP_DROPPED) || 11609 (tp->t_inpcb->inp_flags2 & INP_FREED)) { 11610 panic("tp:%p bbr:%p given a dropped inp:%p", 11611 tp, bbr, tp->t_inpcb); 11612 } 11613 #endif 11614 bbr->r_ctl.rc_flight_at_input = ctf_flight_size(tp, 11615 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 11616 bbr->rtt_valid = 0; 11617 if (to.to_flags & TOF_TS) { 11618 bbr->rc_ts_valid = 1; 11619 bbr->r_ctl.last_inbound_ts = to.to_tsval; 11620 } else { 11621 bbr->rc_ts_valid = 0; 11622 bbr->r_ctl.last_inbound_ts = 0; 11623 } 11624 retval = (*bbr->r_substate) (m, th, so, 11625 tp, &to, drop_hdrlen, 11626 tlen, tiwin, thflags, nxt_pkt, iptos); 11627 #ifdef BBR_INVARIANTS 11628 if ((retval == 0) && 11629 (tp->t_inpcb == NULL)) { 11630 panic("retval:%d tp:%p t_inpcb:NULL state:%d", 11631 retval, tp, prev_state); 11632 } 11633 #endif 11634 if (nxt_pkt == 0) 11635 BBR_STAT_INC(bbr_rlock_left_ret0); 11636 else 11637 BBR_STAT_INC(bbr_rlock_left_ret1); 11638 if (retval == 0) { 11639 /* 11640 * If retval is 1 the tcb is unlocked and most likely the tp 11641 * is gone. 11642 */ 11643 INP_WLOCK_ASSERT(tp->t_inpcb); 11644 tcp_bbr_xmit_timer_commit(bbr, tp, cts); 11645 if (bbr->rc_is_pkt_epoch_now) 11646 bbr_set_pktepoch(bbr, cts, __LINE__); 11647 bbr_check_bbr_for_state(bbr, cts, __LINE__, (bbr->r_ctl.rc_lost - lost)); 11648 if (nxt_pkt == 0) { 11649 if (bbr->r_wanted_output != 0) { 11650 bbr->rc_output_starts_timer = 0; 11651 did_out = 1; 11652 (void)tp->t_fb->tfb_tcp_output(tp); 11653 } else 11654 bbr_start_hpts_timer(bbr, tp, cts, 6, 0, 0); 11655 } 11656 if ((nxt_pkt == 0) && 11657 ((bbr->r_ctl.rc_hpts_flags & PACE_TMR_MASK) == 0) && 11658 (SEQ_GT(tp->snd_max, tp->snd_una) || 11659 (tp->t_flags & TF_DELACK) || 11660 ((V_tcp_always_keepalive || bbr->rc_inp->inp_socket->so_options & SO_KEEPALIVE) && 11661 (tp->t_state <= TCPS_CLOSING)))) { 11662 /* 11663 * We could not send (probably in the hpts but 11664 * stopped the timer)? 11665 */ 11666 if ((tp->snd_max == tp->snd_una) && 11667 ((tp->t_flags & TF_DELACK) == 0) && 11668 (bbr->rc_inp->inp_in_hpts) && 11669 (bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT)) { 11670 /* 11671 * keep alive not needed if we are hptsi 11672 * output yet 11673 */ 11674 ; 11675 } else { 11676 if (bbr->rc_inp->inp_in_hpts) { 11677 tcp_hpts_remove(bbr->rc_inp, HPTS_REMOVE_OUTPUT); 11678 if ((bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) && 11679 (TSTMP_GT(lcts, bbr->rc_pacer_started))) { 11680 uint32_t del; 11681 11682 del = lcts - bbr->rc_pacer_started; 11683 if (bbr->r_ctl.rc_last_delay_val > del) { 11684 BBR_STAT_INC(bbr_force_timer_start); 11685 bbr->r_ctl.rc_last_delay_val -= del; 11686 bbr->rc_pacer_started = lcts; 11687 } else { 11688 /* We are late */ 11689 bbr->r_ctl.rc_last_delay_val = 0; 11690 BBR_STAT_INC(bbr_force_output); 11691 (void)tp->t_fb->tfb_tcp_output(tp); 11692 } 11693 } 11694 } 11695 bbr_start_hpts_timer(bbr, tp, cts, 8, bbr->r_ctl.rc_last_delay_val, 11696 0); 11697 } 11698 } else if ((bbr->rc_output_starts_timer == 0) && (nxt_pkt == 0)) { 11699 /* Do we have the correct timer running? */ 11700 bbr_timer_audit(tp, bbr, lcts, &so->so_snd); 11701 } 11702 /* Do we have a new state */ 11703 if (bbr->r_state != tp->t_state) 11704 bbr_set_state(tp, bbr, tiwin); 11705 done_with_input: 11706 bbr_log_doseg_done(bbr, cts, nxt_pkt, did_out); 11707 if (did_out) 11708 bbr->r_wanted_output = 0; 11709 #ifdef BBR_INVARIANTS 11710 if (tp->t_inpcb == NULL) { 11711 panic("OP:%d retval:%d tp:%p t_inpcb:NULL state:%d", 11712 did_out, 11713 retval, tp, prev_state); 11714 } 11715 #endif 11716 } 11717 return (retval); 11718 } 11719 11720 static void 11721 bbr_do_segment(struct mbuf *m, struct tcphdr *th, struct socket *so, 11722 struct tcpcb *tp, int32_t drop_hdrlen, int32_t tlen, uint8_t iptos) 11723 { 11724 struct timeval tv; 11725 int retval; 11726 11727 /* First lets see if we have old packets */ 11728 if (tp->t_in_pkt) { 11729 if (ctf_do_queued_segments(so, tp, 1)) { 11730 m_freem(m); 11731 return; 11732 } 11733 } 11734 if (m->m_flags & M_TSTMP_LRO) { 11735 tv.tv_sec = m->m_pkthdr.rcv_tstmp /1000000000; 11736 tv.tv_usec = (m->m_pkthdr.rcv_tstmp % 1000000000)/1000; 11737 } else { 11738 /* Should not be should we kassert instead? */ 11739 tcp_get_usecs(&tv); 11740 } 11741 retval = bbr_do_segment_nounlock(m, th, so, tp, 11742 drop_hdrlen, tlen, iptos, 0, &tv); 11743 if (retval == 0) 11744 INP_WUNLOCK(tp->t_inpcb); 11745 } 11746 11747 /* 11748 * Return how much data can be sent without violating the 11749 * cwnd or rwnd. 11750 */ 11751 11752 static inline uint32_t 11753 bbr_what_can_we_send(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t sendwin, 11754 uint32_t avail, int32_t sb_offset, uint32_t cts) 11755 { 11756 uint32_t len; 11757 11758 if (ctf_outstanding(tp) >= tp->snd_wnd) { 11759 /* We never want to go over our peers rcv-window */ 11760 len = 0; 11761 } else { 11762 uint32_t flight; 11763 11764 flight = ctf_flight_size(tp, (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)); 11765 if (flight >= sendwin) { 11766 /* 11767 * We have in flight what we are allowed by cwnd (if 11768 * it was rwnd blocking it would have hit above out 11769 * >= tp->snd_wnd). 11770 */ 11771 return (0); 11772 } 11773 len = sendwin - flight; 11774 if ((len + ctf_outstanding(tp)) > tp->snd_wnd) { 11775 /* We would send too much (beyond the rwnd) */ 11776 len = tp->snd_wnd - ctf_outstanding(tp); 11777 } 11778 if ((len + sb_offset) > avail) { 11779 /* 11780 * We don't have that much in the SB, how much is 11781 * there? 11782 */ 11783 len = avail - sb_offset; 11784 } 11785 } 11786 return (len); 11787 } 11788 11789 static inline void 11790 bbr_do_error_accounting(struct tcpcb *tp, struct tcp_bbr *bbr, struct bbr_sendmap *rsm, int32_t len, int32_t error) 11791 { 11792 #ifdef NETFLIX_STATS 11793 KMOD_TCPSTAT_INC(tcps_sndpack_error); 11794 KMOD_TCPSTAT_ADD(tcps_sndbyte_error, len); 11795 #endif 11796 } 11797 11798 static inline void 11799 bbr_do_send_accounting(struct tcpcb *tp, struct tcp_bbr *bbr, struct bbr_sendmap *rsm, int32_t len, int32_t error) 11800 { 11801 if (error) { 11802 bbr_do_error_accounting(tp, bbr, rsm, len, error); 11803 return; 11804 } 11805 if (rsm) { 11806 if (rsm->r_flags & BBR_TLP) { 11807 /* 11808 * TLP should not count in retran count, but in its 11809 * own bin 11810 */ 11811 #ifdef NETFLIX_STATS 11812 tp->t_sndtlppack++; 11813 tp->t_sndtlpbyte += len; 11814 KMOD_TCPSTAT_INC(tcps_tlpresends); 11815 KMOD_TCPSTAT_ADD(tcps_tlpresend_bytes, len); 11816 #endif 11817 } else { 11818 /* Retransmit */ 11819 tp->t_sndrexmitpack++; 11820 KMOD_TCPSTAT_INC(tcps_sndrexmitpack); 11821 KMOD_TCPSTAT_ADD(tcps_sndrexmitbyte, len); 11822 #ifdef STATS 11823 stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_RETXPB, 11824 len); 11825 #endif 11826 } 11827 /* 11828 * Logs in 0 - 8, 8 is all non probe_bw states 0-7 is 11829 * sub-state 11830 */ 11831 counter_u64_add(bbr_state_lost[rsm->r_bbr_state], len); 11832 if (bbr->rc_bbr_state != BBR_STATE_PROBE_BW) { 11833 /* Non probe_bw log in 1, 2, or 4. */ 11834 counter_u64_add(bbr_state_resend[bbr->rc_bbr_state], len); 11835 } else { 11836 /* 11837 * Log our probe state 3, and log also 5-13 to show 11838 * us the recovery sub-state for the send. This 11839 * means that 3 == (5+6+7+8+9+10+11+12+13) 11840 */ 11841 counter_u64_add(bbr_state_resend[BBR_STATE_PROBE_BW], len); 11842 counter_u64_add(bbr_state_resend[(bbr_state_val(bbr) + 5)], len); 11843 } 11844 /* Place in both 16's the totals of retransmitted */ 11845 counter_u64_add(bbr_state_lost[16], len); 11846 counter_u64_add(bbr_state_resend[16], len); 11847 /* Place in 17's the total sent */ 11848 counter_u64_add(bbr_state_resend[17], len); 11849 counter_u64_add(bbr_state_lost[17], len); 11850 11851 } else { 11852 /* New sends */ 11853 KMOD_TCPSTAT_INC(tcps_sndpack); 11854 KMOD_TCPSTAT_ADD(tcps_sndbyte, len); 11855 /* Place in 17's the total sent */ 11856 counter_u64_add(bbr_state_resend[17], len); 11857 counter_u64_add(bbr_state_lost[17], len); 11858 #ifdef STATS 11859 stats_voi_update_abs_u64(tp->t_stats, VOI_TCP_TXPB, 11860 len); 11861 #endif 11862 } 11863 } 11864 11865 static void 11866 bbr_cwnd_limiting(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t in_level) 11867 { 11868 if (bbr->rc_filled_pipe && bbr_target_cwnd_mult_limit && (bbr->rc_use_google == 0)) { 11869 /* 11870 * Limit the cwnd to not be above N x the target plus whats 11871 * is outstanding. The target is based on the current b/w 11872 * estimate. 11873 */ 11874 uint32_t target; 11875 11876 target = bbr_get_target_cwnd(bbr, bbr_get_bw(bbr), BBR_UNIT); 11877 target += ctf_outstanding(tp); 11878 target *= bbr_target_cwnd_mult_limit; 11879 if (tp->snd_cwnd > target) 11880 tp->snd_cwnd = target; 11881 bbr_log_type_cwndupd(bbr, 0, 0, 0, 10, 0, 0, __LINE__); 11882 } 11883 } 11884 11885 static int 11886 bbr_window_update_needed(struct tcpcb *tp, struct socket *so, uint32_t recwin, int32_t maxseg) 11887 { 11888 /* 11889 * "adv" is the amount we could increase the window, taking into 11890 * account that we are limited by TCP_MAXWIN << tp->rcv_scale. 11891 */ 11892 int32_t adv; 11893 int32_t oldwin; 11894 11895 adv = recwin; 11896 if (SEQ_GT(tp->rcv_adv, tp->rcv_nxt)) { 11897 oldwin = (tp->rcv_adv - tp->rcv_nxt); 11898 if (adv > oldwin) 11899 adv -= oldwin; 11900 else { 11901 /* We can't increase the window */ 11902 adv = 0; 11903 } 11904 } else 11905 oldwin = 0; 11906 11907 /* 11908 * If the new window size ends up being the same as or less 11909 * than the old size when it is scaled, then don't force 11910 * a window update. 11911 */ 11912 if (oldwin >> tp->rcv_scale >= (adv + oldwin) >> tp->rcv_scale) 11913 return (0); 11914 11915 if (adv >= (2 * maxseg) && 11916 (adv >= (so->so_rcv.sb_hiwat / 4) || 11917 recwin <= (so->so_rcv.sb_hiwat / 8) || 11918 so->so_rcv.sb_hiwat <= 8 * maxseg)) { 11919 return (1); 11920 } 11921 if (2 * adv >= (int32_t) so->so_rcv.sb_hiwat) 11922 return (1); 11923 return (0); 11924 } 11925 11926 /* 11927 * Return 0 on success and a errno on failure to send. 11928 * Note that a 0 return may not mean we sent anything 11929 * if the TCB was on the hpts. A non-zero return 11930 * does indicate the error we got from ip[6]_output. 11931 */ 11932 static int 11933 bbr_output_wtime(struct tcpcb *tp, const struct timeval *tv) 11934 { 11935 struct socket *so; 11936 int32_t len; 11937 uint32_t cts; 11938 uint32_t recwin, sendwin; 11939 int32_t sb_offset; 11940 int32_t flags, abandon, error = 0; 11941 struct tcp_log_buffer *lgb = NULL; 11942 struct mbuf *m; 11943 struct mbuf *mb; 11944 uint32_t if_hw_tsomaxsegcount = 0; 11945 uint32_t if_hw_tsomaxsegsize = 0; 11946 uint32_t if_hw_tsomax = 0; 11947 struct ip *ip = NULL; 11948 #ifdef TCPDEBUG 11949 struct ipovly *ipov = NULL; 11950 #endif 11951 struct tcp_bbr *bbr; 11952 struct tcphdr *th; 11953 #ifdef NETFLIX_TCPOUDP 11954 struct udphdr *udp = NULL; 11955 #endif 11956 u_char opt[TCP_MAXOLEN]; 11957 unsigned ipoptlen, optlen, hdrlen; 11958 #ifdef NETFLIX_TCPOUDP 11959 unsigned ulen; 11960 #endif 11961 uint32_t bbr_seq; 11962 uint32_t delay_calc=0; 11963 uint8_t doing_tlp = 0; 11964 uint8_t local_options; 11965 #ifdef BBR_INVARIANTS 11966 uint8_t doing_retran_from = 0; 11967 uint8_t picked_up_retran = 0; 11968 #endif 11969 uint8_t wanted_cookie = 0; 11970 uint8_t more_to_rxt=0; 11971 int32_t prefetch_so_done = 0; 11972 int32_t prefetch_rsm = 0; 11973 uint32_t what_we_can = 0; 11974 uint32_t tot_len = 0; 11975 uint32_t rtr_cnt = 0; 11976 uint32_t maxseg, pace_max_segs, p_maxseg; 11977 int32_t csum_flags; 11978 int32_t hw_tls; 11979 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 11980 unsigned ipsec_optlen = 0; 11981 11982 #endif 11983 volatile int32_t sack_rxmit; 11984 struct bbr_sendmap *rsm = NULL; 11985 int32_t tso, mtu; 11986 struct tcpopt to; 11987 int32_t slot = 0; 11988 struct inpcb *inp; 11989 struct sockbuf *sb; 11990 uint32_t hpts_calling; 11991 #ifdef INET6 11992 struct ip6_hdr *ip6 = NULL; 11993 int32_t isipv6; 11994 #endif 11995 uint8_t app_limited = BBR_JR_SENT_DATA; 11996 uint8_t filled_all = 0; 11997 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 11998 /* We take a cache hit here */ 11999 memcpy(&bbr->rc_tv, tv, sizeof(struct timeval)); 12000 cts = tcp_tv_to_usectick(&bbr->rc_tv); 12001 inp = bbr->rc_inp; 12002 so = inp->inp_socket; 12003 sb = &so->so_snd; 12004 if (sb->sb_flags & SB_TLS_IFNET) 12005 hw_tls = 1; 12006 else 12007 hw_tls = 0; 12008 kern_prefetch(sb, &maxseg); 12009 maxseg = tp->t_maxseg - bbr->rc_last_options; 12010 if (bbr_minseg(bbr) < maxseg) { 12011 tcp_bbr_tso_size_check(bbr, cts); 12012 } 12013 /* Remove any flags that indicate we are pacing on the inp */ 12014 pace_max_segs = bbr->r_ctl.rc_pace_max_segs; 12015 p_maxseg = min(maxseg, pace_max_segs); 12016 INP_WLOCK_ASSERT(inp); 12017 #ifdef TCP_OFFLOAD 12018 if (tp->t_flags & TF_TOE) 12019 return (tcp_offload_output(tp)); 12020 #endif 12021 12022 #ifdef INET6 12023 if (bbr->r_state) { 12024 /* Use the cache line loaded if possible */ 12025 isipv6 = bbr->r_is_v6; 12026 } else { 12027 isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 12028 } 12029 #endif 12030 if (((bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) == 0) && 12031 inp->inp_in_hpts) { 12032 /* 12033 * We are on the hpts for some timer but not hptsi output. 12034 * Possibly remove from the hpts so we can send/recv etc. 12035 */ 12036 if ((tp->t_flags & TF_ACKNOW) == 0) { 12037 /* 12038 * No immediate demand right now to send an ack, but 12039 * the user may have read, making room for new data 12040 * (a window update). If so we may want to cancel 12041 * whatever timer is running (KEEP/DEL-ACK?) and 12042 * continue to send out a window update. Or we may 12043 * have gotten more data into the socket buffer to 12044 * send. 12045 */ 12046 recwin = lmin(lmax(sbspace(&so->so_rcv), 0), 12047 (long)TCP_MAXWIN << tp->rcv_scale); 12048 if ((bbr_window_update_needed(tp, so, recwin, maxseg) == 0) && 12049 ((tcp_outflags[tp->t_state] & TH_RST) == 0) && 12050 ((sbavail(sb) + ((tcp_outflags[tp->t_state] & TH_FIN) ? 1 : 0)) <= 12051 (tp->snd_max - tp->snd_una))) { 12052 /* 12053 * Nothing new to send and no window update 12054 * is needed to send. Lets just return and 12055 * let the timer-run off. 12056 */ 12057 return (0); 12058 } 12059 } 12060 tcp_hpts_remove(inp, HPTS_REMOVE_OUTPUT); 12061 bbr_timer_cancel(bbr, __LINE__, cts); 12062 } 12063 if (bbr->r_ctl.rc_last_delay_val) { 12064 /* Calculate a rough delay for early escape to sending */ 12065 if (SEQ_GT(cts, bbr->rc_pacer_started)) 12066 delay_calc = cts - bbr->rc_pacer_started; 12067 if (delay_calc >= bbr->r_ctl.rc_last_delay_val) 12068 delay_calc -= bbr->r_ctl.rc_last_delay_val; 12069 else 12070 delay_calc = 0; 12071 } 12072 /* Mark that we have called bbr_output(). */ 12073 if ((bbr->r_timer_override) || 12074 (tp->t_state < TCPS_ESTABLISHED)) { 12075 /* Timeouts or early states are exempt */ 12076 if (inp->inp_in_hpts) 12077 tcp_hpts_remove(inp, HPTS_REMOVE_OUTPUT); 12078 } else if (inp->inp_in_hpts) { 12079 if ((bbr->r_ctl.rc_last_delay_val) && 12080 (bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) && 12081 delay_calc) { 12082 /* 12083 * We were being paced for output and the delay has 12084 * already exceeded when we were supposed to be 12085 * called, lets go ahead and pull out of the hpts 12086 * and call output. 12087 */ 12088 counter_u64_add(bbr_out_size[TCP_MSS_ACCT_LATE], 1); 12089 bbr->r_ctl.rc_last_delay_val = 0; 12090 tcp_hpts_remove(inp, HPTS_REMOVE_OUTPUT); 12091 } else if (tp->t_state == TCPS_CLOSED) { 12092 bbr->r_ctl.rc_last_delay_val = 0; 12093 tcp_hpts_remove(inp, HPTS_REMOVE_OUTPUT); 12094 } else { 12095 /* 12096 * On the hpts, you shall not pass! even if ACKNOW 12097 * is on, we will when the hpts fires, unless of 12098 * course we are overdue. 12099 */ 12100 counter_u64_add(bbr_out_size[TCP_MSS_ACCT_INPACE], 1); 12101 return (0); 12102 } 12103 } 12104 bbr->rc_cwnd_limited = 0; 12105 if (bbr->r_ctl.rc_last_delay_val) { 12106 /* recalculate the real delay and deal with over/under */ 12107 if (SEQ_GT(cts, bbr->rc_pacer_started)) 12108 delay_calc = cts - bbr->rc_pacer_started; 12109 else 12110 delay_calc = 0; 12111 if (delay_calc >= bbr->r_ctl.rc_last_delay_val) 12112 /* Setup the delay which will be added in */ 12113 delay_calc -= bbr->r_ctl.rc_last_delay_val; 12114 else { 12115 /* 12116 * We are early setup to adjust 12117 * our slot time. 12118 */ 12119 uint64_t merged_val; 12120 12121 bbr->r_ctl.rc_agg_early += (bbr->r_ctl.rc_last_delay_val - delay_calc); 12122 bbr->r_agg_early_set = 1; 12123 if (bbr->r_ctl.rc_hptsi_agg_delay) { 12124 if (bbr->r_ctl.rc_hptsi_agg_delay >= bbr->r_ctl.rc_agg_early) { 12125 /* Nope our previous late cancels out the early */ 12126 bbr->r_ctl.rc_hptsi_agg_delay -= bbr->r_ctl.rc_agg_early; 12127 bbr->r_agg_early_set = 0; 12128 bbr->r_ctl.rc_agg_early = 0; 12129 } else { 12130 bbr->r_ctl.rc_agg_early -= bbr->r_ctl.rc_hptsi_agg_delay; 12131 bbr->r_ctl.rc_hptsi_agg_delay = 0; 12132 } 12133 } 12134 merged_val = bbr->rc_pacer_started; 12135 merged_val <<= 32; 12136 merged_val |= bbr->r_ctl.rc_last_delay_val; 12137 bbr_log_pacing_delay_calc(bbr, inp->inp_hpts_calls, 12138 bbr->r_ctl.rc_agg_early, cts, delay_calc, merged_val, 12139 bbr->r_agg_early_set, 3); 12140 bbr->r_ctl.rc_last_delay_val = 0; 12141 BBR_STAT_INC(bbr_early); 12142 delay_calc = 0; 12143 } 12144 } else { 12145 /* We were not delayed due to hptsi */ 12146 if (bbr->r_agg_early_set) 12147 bbr->r_ctl.rc_agg_early = 0; 12148 bbr->r_agg_early_set = 0; 12149 delay_calc = 0; 12150 } 12151 if (delay_calc) { 12152 /* 12153 * We had a hptsi delay which means we are falling behind on 12154 * sending at the expected rate. Calculate an extra amount 12155 * of data we can send, if any, to put us back on track. 12156 */ 12157 if ((bbr->r_ctl.rc_hptsi_agg_delay + delay_calc) < bbr->r_ctl.rc_hptsi_agg_delay) 12158 bbr->r_ctl.rc_hptsi_agg_delay = 0xffffffff; 12159 else 12160 bbr->r_ctl.rc_hptsi_agg_delay += delay_calc; 12161 } 12162 sendwin = min(tp->snd_wnd, tp->snd_cwnd); 12163 if ((tp->snd_una == tp->snd_max) && 12164 (bbr->rc_bbr_state != BBR_STATE_IDLE_EXIT) && 12165 (sbavail(sb))) { 12166 /* 12167 * Ok we have been idle with nothing outstanding 12168 * we possibly need to start fresh with either a new 12169 * suite of states or a fast-ramp up. 12170 */ 12171 bbr_restart_after_idle(bbr, 12172 cts, bbr_calc_time(cts, bbr->r_ctl.rc_went_idle_time)); 12173 } 12174 /* 12175 * Now was there a hptsi delay where we are behind? We only count 12176 * being behind if: a) We are not in recovery. b) There was a delay. 12177 * <and> c) We had room to send something. 12178 * 12179 */ 12180 hpts_calling = inp->inp_hpts_calls; 12181 inp->inp_hpts_calls = 0; 12182 if (bbr->r_ctl.rc_hpts_flags & PACE_TMR_MASK) { 12183 if (bbr_process_timers(tp, bbr, cts, hpts_calling)) { 12184 counter_u64_add(bbr_out_size[TCP_MSS_ACCT_ATIMER], 1); 12185 return (0); 12186 } 12187 } 12188 bbr->rc_inp->inp_flags2 &= ~INP_MBUF_QUEUE_READY; 12189 if (hpts_calling && 12190 (bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT)) { 12191 bbr->r_ctl.rc_last_delay_val = 0; 12192 } 12193 bbr->r_timer_override = 0; 12194 bbr->r_wanted_output = 0; 12195 /* 12196 * For TFO connections in SYN_RECEIVED, only allow the initial 12197 * SYN|ACK and those sent by the retransmit timer. 12198 */ 12199 if (IS_FASTOPEN(tp->t_flags) && 12200 ((tp->t_state == TCPS_SYN_RECEIVED) || 12201 (tp->t_state == TCPS_SYN_SENT)) && 12202 SEQ_GT(tp->snd_max, tp->snd_una) && /* initial SYN or SYN|ACK sent */ 12203 (tp->t_rxtshift == 0)) { /* not a retransmit */ 12204 len = 0; 12205 goto just_return_nolock; 12206 } 12207 /* 12208 * Before sending anything check for a state update. For hpts 12209 * calling without input this is important. If its input calling 12210 * then this was already done. 12211 */ 12212 if (bbr->rc_use_google == 0) 12213 bbr_check_bbr_for_state(bbr, cts, __LINE__, 0); 12214 again: 12215 /* 12216 * If we've recently taken a timeout, snd_max will be greater than 12217 * snd_max. BBR in general does not pay much attention to snd_nxt 12218 * for historic reasons the persist timer still uses it. This means 12219 * we have to look at it. All retransmissions that are not persits 12220 * use the rsm that needs to be sent so snd_nxt is ignored. At the 12221 * end of this routine we pull snd_nxt always up to snd_max. 12222 */ 12223 doing_tlp = 0; 12224 #ifdef BBR_INVARIANTS 12225 doing_retran_from = picked_up_retran = 0; 12226 #endif 12227 error = 0; 12228 tso = 0; 12229 slot = 0; 12230 mtu = 0; 12231 sendwin = min(tp->snd_wnd, tp->snd_cwnd); 12232 sb_offset = tp->snd_max - tp->snd_una; 12233 flags = tcp_outflags[tp->t_state]; 12234 sack_rxmit = 0; 12235 len = 0; 12236 rsm = NULL; 12237 if (flags & TH_RST) { 12238 SOCKBUF_LOCK(sb); 12239 goto send; 12240 } 12241 recheck_resend: 12242 while (bbr->r_ctl.rc_free_cnt < bbr_min_req_free) { 12243 /* We need to always have one in reserve */ 12244 rsm = bbr_alloc(bbr); 12245 if (rsm == NULL) { 12246 error = ENOMEM; 12247 /* Lie to get on the hpts */ 12248 tot_len = tp->t_maxseg; 12249 if (hpts_calling) 12250 /* Retry in a ms */ 12251 slot = 1001; 12252 goto just_return_nolock; 12253 } 12254 TAILQ_INSERT_TAIL(&bbr->r_ctl.rc_free, rsm, r_next); 12255 bbr->r_ctl.rc_free_cnt++; 12256 rsm = NULL; 12257 } 12258 /* What do we send, a resend? */ 12259 if (bbr->r_ctl.rc_resend == NULL) { 12260 /* Check for rack timeout */ 12261 bbr->r_ctl.rc_resend = bbr_check_recovery_mode(tp, bbr, cts); 12262 if (bbr->r_ctl.rc_resend) { 12263 #ifdef BBR_INVARIANTS 12264 picked_up_retran = 1; 12265 #endif 12266 bbr_cong_signal(tp, NULL, CC_NDUPACK, bbr->r_ctl.rc_resend); 12267 } 12268 } 12269 if (bbr->r_ctl.rc_resend) { 12270 rsm = bbr->r_ctl.rc_resend; 12271 #ifdef BBR_INVARIANTS 12272 doing_retran_from = 1; 12273 #endif 12274 /* Remove any TLP flags its a RACK or T-O */ 12275 rsm->r_flags &= ~BBR_TLP; 12276 bbr->r_ctl.rc_resend = NULL; 12277 if (SEQ_LT(rsm->r_start, tp->snd_una)) { 12278 #ifdef BBR_INVARIANTS 12279 panic("Huh, tp:%p bbr:%p rsm:%p start:%u < snd_una:%u\n", 12280 tp, bbr, rsm, rsm->r_start, tp->snd_una); 12281 goto recheck_resend; 12282 #else 12283 /* TSNH */ 12284 rsm = NULL; 12285 goto recheck_resend; 12286 #endif 12287 } 12288 rtr_cnt++; 12289 if (rsm->r_flags & BBR_HAS_SYN) { 12290 /* Only retransmit a SYN by itself */ 12291 len = 0; 12292 if ((flags & TH_SYN) == 0) { 12293 /* Huh something is wrong */ 12294 rsm->r_start++; 12295 if (rsm->r_start == rsm->r_end) { 12296 /* Clean it up, somehow we missed the ack? */ 12297 bbr_log_syn(tp, NULL); 12298 } else { 12299 /* TFO with data? */ 12300 rsm->r_flags &= ~BBR_HAS_SYN; 12301 len = rsm->r_end - rsm->r_start; 12302 } 12303 } else { 12304 /* Retransmitting SYN */ 12305 rsm = NULL; 12306 SOCKBUF_LOCK(sb); 12307 goto send; 12308 } 12309 } else 12310 len = rsm->r_end - rsm->r_start; 12311 if ((bbr->rc_resends_use_tso == 0) && 12312 (len > maxseg)) { 12313 len = maxseg; 12314 more_to_rxt = 1; 12315 } 12316 sb_offset = rsm->r_start - tp->snd_una; 12317 if (len > 0) { 12318 sack_rxmit = 1; 12319 KMOD_TCPSTAT_INC(tcps_sack_rexmits); 12320 KMOD_TCPSTAT_ADD(tcps_sack_rexmit_bytes, 12321 min(len, maxseg)); 12322 } else { 12323 /* I dont think this can happen */ 12324 rsm = NULL; 12325 goto recheck_resend; 12326 } 12327 BBR_STAT_INC(bbr_resends_set); 12328 } else if (bbr->r_ctl.rc_tlp_send) { 12329 /* 12330 * Tail loss probe 12331 */ 12332 doing_tlp = 1; 12333 rsm = bbr->r_ctl.rc_tlp_send; 12334 bbr->r_ctl.rc_tlp_send = NULL; 12335 sack_rxmit = 1; 12336 len = rsm->r_end - rsm->r_start; 12337 rtr_cnt++; 12338 if ((bbr->rc_resends_use_tso == 0) && (len > maxseg)) 12339 len = maxseg; 12340 12341 if (SEQ_GT(tp->snd_una, rsm->r_start)) { 12342 #ifdef BBR_INVARIANTS 12343 panic("tp:%p bbc:%p snd_una:%u rsm:%p r_start:%u", 12344 tp, bbr, tp->snd_una, rsm, rsm->r_start); 12345 #else 12346 /* TSNH */ 12347 rsm = NULL; 12348 goto recheck_resend; 12349 #endif 12350 } 12351 sb_offset = rsm->r_start - tp->snd_una; 12352 BBR_STAT_INC(bbr_tlp_set); 12353 } 12354 /* 12355 * Enforce a connection sendmap count limit if set 12356 * as long as we are not retransmiting. 12357 */ 12358 if ((rsm == NULL) && 12359 (V_tcp_map_entries_limit > 0) && 12360 (bbr->r_ctl.rc_num_maps_alloced >= V_tcp_map_entries_limit)) { 12361 BBR_STAT_INC(bbr_alloc_limited); 12362 if (!bbr->alloc_limit_reported) { 12363 bbr->alloc_limit_reported = 1; 12364 BBR_STAT_INC(bbr_alloc_limited_conns); 12365 } 12366 goto just_return_nolock; 12367 } 12368 #ifdef BBR_INVARIANTS 12369 if (rsm && SEQ_LT(rsm->r_start, tp->snd_una)) { 12370 panic("tp:%p bbr:%p rsm:%p sb_offset:%u len:%u", 12371 tp, bbr, rsm, sb_offset, len); 12372 } 12373 #endif 12374 /* 12375 * Get standard flags, and add SYN or FIN if requested by 'hidden' 12376 * state flags. 12377 */ 12378 if (tp->t_flags & TF_NEEDFIN && (rsm == NULL)) 12379 flags |= TH_FIN; 12380 if (tp->t_flags & TF_NEEDSYN) 12381 flags |= TH_SYN; 12382 12383 if (rsm && (rsm->r_flags & BBR_HAS_FIN)) { 12384 /* we are retransmitting the fin */ 12385 len--; 12386 if (len) { 12387 /* 12388 * When retransmitting data do *not* include the 12389 * FIN. This could happen from a TLP probe if we 12390 * allowed data with a FIN. 12391 */ 12392 flags &= ~TH_FIN; 12393 } 12394 } else if (rsm) { 12395 if (flags & TH_FIN) 12396 flags &= ~TH_FIN; 12397 } 12398 if ((sack_rxmit == 0) && (prefetch_rsm == 0)) { 12399 void *end_rsm; 12400 12401 end_rsm = TAILQ_LAST_FAST(&bbr->r_ctl.rc_tmap, bbr_sendmap, r_tnext); 12402 if (end_rsm) 12403 kern_prefetch(end_rsm, &prefetch_rsm); 12404 prefetch_rsm = 1; 12405 } 12406 SOCKBUF_LOCK(sb); 12407 /* 12408 * If snd_nxt == snd_max and we have transmitted a FIN, the 12409 * sb_offset will be > 0 even if so_snd.sb_cc is 0, resulting in a 12410 * negative length. This can also occur when TCP opens up its 12411 * congestion window while receiving additional duplicate acks after 12412 * fast-retransmit because TCP will reset snd_nxt to snd_max after 12413 * the fast-retransmit. 12414 * 12415 * In the normal retransmit-FIN-only case, however, snd_nxt will be 12416 * set to snd_una, the sb_offset will be 0, and the length may wind 12417 * up 0. 12418 * 12419 * If sack_rxmit is true we are retransmitting from the scoreboard 12420 * in which case len is already set. 12421 */ 12422 if (sack_rxmit == 0) { 12423 uint32_t avail; 12424 12425 avail = sbavail(sb); 12426 if (SEQ_GT(tp->snd_max, tp->snd_una)) 12427 sb_offset = tp->snd_max - tp->snd_una; 12428 else 12429 sb_offset = 0; 12430 if (bbr->rc_tlp_new_data) { 12431 /* TLP is forcing out new data */ 12432 uint32_t tlplen; 12433 12434 doing_tlp = 1; 12435 tlplen = maxseg; 12436 12437 if (tlplen > (uint32_t)(avail - sb_offset)) { 12438 tlplen = (uint32_t)(avail - sb_offset); 12439 } 12440 if (tlplen > tp->snd_wnd) { 12441 len = tp->snd_wnd; 12442 } else { 12443 len = tlplen; 12444 } 12445 bbr->rc_tlp_new_data = 0; 12446 } else { 12447 what_we_can = len = bbr_what_can_we_send(tp, bbr, sendwin, avail, sb_offset, cts); 12448 if ((len < p_maxseg) && 12449 (bbr->rc_in_persist == 0) && 12450 (ctf_outstanding(tp) >= (2 * p_maxseg)) && 12451 ((avail - sb_offset) >= p_maxseg)) { 12452 /* 12453 * We are not completing whats in the socket 12454 * buffer (i.e. there is at least a segment 12455 * waiting to send) and we have 2 or more 12456 * segments outstanding. There is no sense 12457 * of sending a little piece. Lets defer and 12458 * and wait until we can send a whole 12459 * segment. 12460 */ 12461 len = 0; 12462 } 12463 if (bbr->rc_in_persist) { 12464 /* 12465 * We are in persists, figure out if 12466 * a retransmit is available (maybe the previous 12467 * persists we sent) or if we have to send new 12468 * data. 12469 */ 12470 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map); 12471 if (rsm) { 12472 len = rsm->r_end - rsm->r_start; 12473 if (rsm->r_flags & BBR_HAS_FIN) 12474 len--; 12475 if ((bbr->rc_resends_use_tso == 0) && (len > maxseg)) 12476 len = maxseg; 12477 if (len > 1) 12478 BBR_STAT_INC(bbr_persist_reneg); 12479 /* 12480 * XXXrrs we could force the len to 12481 * 1 byte here to cause the chunk to 12482 * split apart.. but that would then 12483 * mean we always retransmit it as 12484 * one byte even after the window 12485 * opens. 12486 */ 12487 sack_rxmit = 1; 12488 sb_offset = rsm->r_start - tp->snd_una; 12489 } else { 12490 /* 12491 * First time through in persists or peer 12492 * acked our one byte. Though we do have 12493 * to have something in the sb. 12494 */ 12495 len = 1; 12496 sb_offset = 0; 12497 if (avail == 0) 12498 len = 0; 12499 } 12500 } 12501 } 12502 } 12503 if (prefetch_so_done == 0) { 12504 kern_prefetch(so, &prefetch_so_done); 12505 prefetch_so_done = 1; 12506 } 12507 /* 12508 * Lop off SYN bit if it has already been sent. However, if this is 12509 * SYN-SENT state and if segment contains data and if we don't know 12510 * that foreign host supports TAO, suppress sending segment. 12511 */ 12512 if ((flags & TH_SYN) && (rsm == NULL) && 12513 SEQ_GT(tp->snd_max, tp->snd_una)) { 12514 if (tp->t_state != TCPS_SYN_RECEIVED) 12515 flags &= ~TH_SYN; 12516 /* 12517 * When sending additional segments following a TFO SYN|ACK, 12518 * do not include the SYN bit. 12519 */ 12520 if (IS_FASTOPEN(tp->t_flags) && 12521 (tp->t_state == TCPS_SYN_RECEIVED)) 12522 flags &= ~TH_SYN; 12523 sb_offset--, len++; 12524 if (sbavail(sb) == 0) 12525 len = 0; 12526 } else if ((flags & TH_SYN) && rsm) { 12527 /* 12528 * Subtract one from the len for the SYN being 12529 * retransmitted. 12530 */ 12531 len--; 12532 } 12533 /* 12534 * Be careful not to send data and/or FIN on SYN segments. This 12535 * measure is needed to prevent interoperability problems with not 12536 * fully conformant TCP implementations. 12537 */ 12538 if ((flags & TH_SYN) && (tp->t_flags & TF_NOOPT)) { 12539 len = 0; 12540 flags &= ~TH_FIN; 12541 } 12542 /* 12543 * On TFO sockets, ensure no data is sent in the following cases: 12544 * 12545 * - When retransmitting SYN|ACK on a passively-created socket 12546 * - When retransmitting SYN on an actively created socket 12547 * - When sending a zero-length cookie (cookie request) on an 12548 * actively created socket 12549 * - When the socket is in the CLOSED state (RST is being sent) 12550 */ 12551 if (IS_FASTOPEN(tp->t_flags) && 12552 (((flags & TH_SYN) && (tp->t_rxtshift > 0)) || 12553 ((tp->t_state == TCPS_SYN_SENT) && 12554 (tp->t_tfo_client_cookie_len == 0)) || 12555 (flags & TH_RST))) { 12556 len = 0; 12557 sack_rxmit = 0; 12558 rsm = NULL; 12559 } 12560 /* Without fast-open there should never be data sent on a SYN */ 12561 if ((flags & TH_SYN) && (!IS_FASTOPEN(tp->t_flags))) 12562 len = 0; 12563 if (len <= 0) { 12564 /* 12565 * If FIN has been sent but not acked, but we haven't been 12566 * called to retransmit, len will be < 0. Otherwise, window 12567 * shrank after we sent into it. If window shrank to 0, 12568 * cancel pending retransmit, pull snd_nxt back to (closed) 12569 * window, and set the persist timer if it isn't already 12570 * going. If the window didn't close completely, just wait 12571 * for an ACK. 12572 * 12573 * We also do a general check here to ensure that we will 12574 * set the persist timer when we have data to send, but a 12575 * 0-byte window. This makes sure the persist timer is set 12576 * even if the packet hits one of the "goto send" lines 12577 * below. 12578 */ 12579 len = 0; 12580 if ((tp->snd_wnd == 0) && 12581 (TCPS_HAVEESTABLISHED(tp->t_state)) && 12582 (tp->snd_una == tp->snd_max) && 12583 (sb_offset < (int)sbavail(sb))) { 12584 /* 12585 * Not enough room in the rwnd to send 12586 * a paced segment out. 12587 */ 12588 bbr_enter_persist(tp, bbr, cts, __LINE__); 12589 } 12590 } else if ((rsm == NULL) && 12591 (doing_tlp == 0) && 12592 (len < bbr->r_ctl.rc_pace_max_segs)) { 12593 /* 12594 * We are not sending a full segment for 12595 * some reason. Should we not send anything (think 12596 * sws or persists)? 12597 */ 12598 if ((tp->snd_wnd < min((bbr->r_ctl.rc_high_rwnd/2), bbr_minseg(bbr))) && 12599 (TCPS_HAVEESTABLISHED(tp->t_state)) && 12600 (len < (int)(sbavail(sb) - sb_offset))) { 12601 /* 12602 * Here the rwnd is less than 12603 * the pacing size, this is not a retransmit, 12604 * we are established and 12605 * the send is not the last in the socket buffer 12606 * lets not send, and possibly enter persists. 12607 */ 12608 len = 0; 12609 if (tp->snd_max == tp->snd_una) 12610 bbr_enter_persist(tp, bbr, cts, __LINE__); 12611 } else if ((tp->snd_cwnd >= bbr->r_ctl.rc_pace_max_segs) && 12612 (ctf_flight_size(tp, (bbr->r_ctl.rc_sacked + 12613 bbr->r_ctl.rc_lost_bytes)) > (2 * maxseg)) && 12614 (len < (int)(sbavail(sb) - sb_offset)) && 12615 (len < bbr_minseg(bbr))) { 12616 /* 12617 * Here we are not retransmitting, and 12618 * the cwnd is not so small that we could 12619 * not send at least a min size (rxt timer 12620 * not having gone off), We have 2 segments or 12621 * more already in flight, its not the tail end 12622 * of the socket buffer and the cwnd is blocking 12623 * us from sending out minimum pacing segment size. 12624 * Lets not send anything. 12625 */ 12626 bbr->rc_cwnd_limited = 1; 12627 len = 0; 12628 } else if (((tp->snd_wnd - ctf_outstanding(tp)) < 12629 min((bbr->r_ctl.rc_high_rwnd/2), bbr_minseg(bbr))) && 12630 (ctf_flight_size(tp, (bbr->r_ctl.rc_sacked + 12631 bbr->r_ctl.rc_lost_bytes)) > (2 * maxseg)) && 12632 (len < (int)(sbavail(sb) - sb_offset)) && 12633 (TCPS_HAVEESTABLISHED(tp->t_state))) { 12634 /* 12635 * Here we have a send window but we have 12636 * filled it up and we can't send another pacing segment. 12637 * We also have in flight more than 2 segments 12638 * and we are not completing the sb i.e. we allow 12639 * the last bytes of the sb to go out even if 12640 * its not a full pacing segment. 12641 */ 12642 len = 0; 12643 } 12644 } 12645 /* len will be >= 0 after this point. */ 12646 KASSERT(len >= 0, ("[%s:%d]: len < 0", __func__, __LINE__)); 12647 tcp_sndbuf_autoscale(tp, so, sendwin); 12648 /* 12649 * 12650 */ 12651 if (bbr->rc_in_persist && 12652 len && 12653 (rsm == NULL) && 12654 (len < min((bbr->r_ctl.rc_high_rwnd/2), bbr->r_ctl.rc_pace_max_segs))) { 12655 /* 12656 * We are in persist, not doing a retransmit and don't have enough space 12657 * yet to send a full TSO. So is it at the end of the sb 12658 * if so we need to send else nuke to 0 and don't send. 12659 */ 12660 int sbleft; 12661 if (sbavail(sb) > sb_offset) 12662 sbleft = sbavail(sb) - sb_offset; 12663 else 12664 sbleft = 0; 12665 if (sbleft >= min((bbr->r_ctl.rc_high_rwnd/2), bbr->r_ctl.rc_pace_max_segs)) { 12666 /* not at end of sb lets not send */ 12667 len = 0; 12668 } 12669 } 12670 /* 12671 * Decide if we can use TCP Segmentation Offloading (if supported by 12672 * hardware). 12673 * 12674 * TSO may only be used if we are in a pure bulk sending state. The 12675 * presence of TCP-MD5, SACK retransmits, SACK advertizements and IP 12676 * options prevent using TSO. With TSO the TCP header is the same 12677 * (except for the sequence number) for all generated packets. This 12678 * makes it impossible to transmit any options which vary per 12679 * generated segment or packet. 12680 * 12681 * IPv4 handling has a clear separation of ip options and ip header 12682 * flags while IPv6 combines both in in6p_outputopts. ip6_optlen() 12683 * does the right thing below to provide length of just ip options 12684 * and thus checking for ipoptlen is enough to decide if ip options 12685 * are present. 12686 */ 12687 #ifdef INET6 12688 if (isipv6) 12689 ipoptlen = ip6_optlen(inp); 12690 else 12691 #endif 12692 if (inp->inp_options) 12693 ipoptlen = inp->inp_options->m_len - 12694 offsetof(struct ipoption, ipopt_list); 12695 else 12696 ipoptlen = 0; 12697 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 12698 /* 12699 * Pre-calculate here as we save another lookup into the darknesses 12700 * of IPsec that way and can actually decide if TSO is ok. 12701 */ 12702 #ifdef INET6 12703 if (isipv6 && IPSEC_ENABLED(ipv6)) 12704 ipsec_optlen = IPSEC_HDRSIZE(ipv6, inp); 12705 #ifdef INET 12706 else 12707 #endif 12708 #endif /* INET6 */ 12709 #ifdef INET 12710 if (IPSEC_ENABLED(ipv4)) 12711 ipsec_optlen = IPSEC_HDRSIZE(ipv4, inp); 12712 #endif /* INET */ 12713 #endif /* IPSEC */ 12714 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 12715 ipoptlen += ipsec_optlen; 12716 #endif 12717 if ((tp->t_flags & TF_TSO) && V_tcp_do_tso && 12718 (len > maxseg) && 12719 (tp->t_port == 0) && 12720 ((tp->t_flags & TF_SIGNATURE) == 0) && 12721 tp->rcv_numsacks == 0 && 12722 ipoptlen == 0) 12723 tso = 1; 12724 12725 recwin = lmin(lmax(sbspace(&so->so_rcv), 0), 12726 (long)TCP_MAXWIN << tp->rcv_scale); 12727 /* 12728 * Sender silly window avoidance. We transmit under the following 12729 * conditions when len is non-zero: 12730 * 12731 * - We have a full segment (or more with TSO) - This is the last 12732 * buffer in a write()/send() and we are either idle or running 12733 * NODELAY - we've timed out (e.g. persist timer) - we have more 12734 * then 1/2 the maximum send window's worth of data (receiver may be 12735 * limited the window size) - we need to retransmit 12736 */ 12737 if (rsm) 12738 goto send; 12739 if (len) { 12740 if (sack_rxmit) 12741 goto send; 12742 if (len >= p_maxseg) 12743 goto send; 12744 /* 12745 * NOTE! on localhost connections an 'ack' from the remote 12746 * end may occur synchronously with the output and cause us 12747 * to flush a buffer queued with moretocome. XXX 12748 * 12749 */ 12750 if (((tp->t_flags & TF_MORETOCOME) == 0) && /* normal case */ 12751 ((tp->t_flags & TF_NODELAY) || 12752 ((uint32_t)len + (uint32_t)sb_offset) >= sbavail(&so->so_snd)) && 12753 (tp->t_flags & TF_NOPUSH) == 0) { 12754 goto send; 12755 } 12756 if ((tp->snd_una == tp->snd_max) && len) { /* Nothing outstanding */ 12757 goto send; 12758 } 12759 if (len >= tp->max_sndwnd / 2 && tp->max_sndwnd > 0) { 12760 goto send; 12761 } 12762 } 12763 /* 12764 * Sending of standalone window updates. 12765 * 12766 * Window updates are important when we close our window due to a 12767 * full socket buffer and are opening it again after the application 12768 * reads data from it. Once the window has opened again and the 12769 * remote end starts to send again the ACK clock takes over and 12770 * provides the most current window information. 12771 * 12772 * We must avoid the silly window syndrome whereas every read from 12773 * the receive buffer, no matter how small, causes a window update 12774 * to be sent. We also should avoid sending a flurry of window 12775 * updates when the socket buffer had queued a lot of data and the 12776 * application is doing small reads. 12777 * 12778 * Prevent a flurry of pointless window updates by only sending an 12779 * update when we can increase the advertized window by more than 12780 * 1/4th of the socket buffer capacity. When the buffer is getting 12781 * full or is very small be more aggressive and send an update 12782 * whenever we can increase by two mss sized segments. In all other 12783 * situations the ACK's to new incoming data will carry further 12784 * window increases. 12785 * 12786 * Don't send an independent window update if a delayed ACK is 12787 * pending (it will get piggy-backed on it) or the remote side 12788 * already has done a half-close and won't send more data. Skip 12789 * this if the connection is in T/TCP half-open state. 12790 */ 12791 if (recwin > 0 && !(tp->t_flags & TF_NEEDSYN) && 12792 !(tp->t_flags & TF_DELACK) && 12793 !TCPS_HAVERCVDFIN(tp->t_state)) { 12794 /* Check to see if we should do a window update */ 12795 if (bbr_window_update_needed(tp, so, recwin, maxseg)) 12796 goto send; 12797 } 12798 /* 12799 * Send if we owe the peer an ACK, RST, SYN. ACKNOW 12800 * is also a catch-all for the retransmit timer timeout case. 12801 */ 12802 if (tp->t_flags & TF_ACKNOW) { 12803 goto send; 12804 } 12805 if (flags & TH_RST) { 12806 /* Always send a RST if one is due */ 12807 goto send; 12808 } 12809 if ((flags & TH_SYN) && (tp->t_flags & TF_NEEDSYN) == 0) { 12810 goto send; 12811 } 12812 /* 12813 * If our state indicates that FIN should be sent and we have not 12814 * yet done so, then we need to send. 12815 */ 12816 if (flags & TH_FIN && 12817 ((tp->t_flags & TF_SENTFIN) == 0)) { 12818 goto send; 12819 } 12820 /* 12821 * No reason to send a segment, just return. 12822 */ 12823 just_return: 12824 SOCKBUF_UNLOCK(sb); 12825 just_return_nolock: 12826 if (tot_len) 12827 slot = bbr_get_pacing_delay(bbr, bbr->r_ctl.rc_bbr_hptsi_gain, tot_len, cts, 0); 12828 if (bbr->rc_no_pacing) 12829 slot = 0; 12830 if (tot_len == 0) { 12831 if ((ctf_outstanding(tp) + min((bbr->r_ctl.rc_high_rwnd/2), bbr_minseg(bbr))) >= 12832 tp->snd_wnd) { 12833 BBR_STAT_INC(bbr_rwnd_limited); 12834 app_limited = BBR_JR_RWND_LIMITED; 12835 bbr_cwnd_limiting(tp, bbr, ctf_outstanding(tp)); 12836 if ((bbr->rc_in_persist == 0) && 12837 TCPS_HAVEESTABLISHED(tp->t_state) && 12838 (tp->snd_max == tp->snd_una) && 12839 sbavail(&tp->t_inpcb->inp_socket->so_snd)) { 12840 /* No send window.. we must enter persist */ 12841 bbr_enter_persist(tp, bbr, bbr->r_ctl.rc_rcvtime, __LINE__); 12842 } 12843 } else if (ctf_outstanding(tp) >= sbavail(sb)) { 12844 BBR_STAT_INC(bbr_app_limited); 12845 app_limited = BBR_JR_APP_LIMITED; 12846 bbr_cwnd_limiting(tp, bbr, ctf_outstanding(tp)); 12847 } else if ((ctf_flight_size(tp, (bbr->r_ctl.rc_sacked + 12848 bbr->r_ctl.rc_lost_bytes)) + p_maxseg) >= tp->snd_cwnd) { 12849 BBR_STAT_INC(bbr_cwnd_limited); 12850 app_limited = BBR_JR_CWND_LIMITED; 12851 bbr_cwnd_limiting(tp, bbr, ctf_flight_size(tp, (bbr->r_ctl.rc_sacked + 12852 bbr->r_ctl.rc_lost_bytes))); 12853 bbr->rc_cwnd_limited = 1; 12854 } else { 12855 BBR_STAT_INC(bbr_app_limited); 12856 app_limited = BBR_JR_APP_LIMITED; 12857 bbr_cwnd_limiting(tp, bbr, ctf_outstanding(tp)); 12858 } 12859 bbr->r_ctl.rc_hptsi_agg_delay = 0; 12860 bbr->r_agg_early_set = 0; 12861 bbr->r_ctl.rc_agg_early = 0; 12862 bbr->r_ctl.rc_last_delay_val = 0; 12863 } else if (bbr->rc_use_google == 0) 12864 bbr_check_bbr_for_state(bbr, cts, __LINE__, 0); 12865 /* Are we app limited? */ 12866 if ((app_limited == BBR_JR_APP_LIMITED) || 12867 (app_limited == BBR_JR_RWND_LIMITED)) { 12868 /** 12869 * We are application limited. 12870 */ 12871 bbr->r_ctl.r_app_limited_until = (ctf_flight_size(tp, (bbr->r_ctl.rc_sacked + 12872 bbr->r_ctl.rc_lost_bytes)) + bbr->r_ctl.rc_delivered); 12873 } 12874 if (tot_len == 0) 12875 counter_u64_add(bbr_out_size[TCP_MSS_ACCT_JUSTRET], 1); 12876 /* Dont update the time if we did not send */ 12877 bbr->r_ctl.rc_last_delay_val = 0; 12878 bbr->rc_output_starts_timer = 1; 12879 bbr_start_hpts_timer(bbr, tp, cts, 9, slot, tot_len); 12880 bbr_log_type_just_return(bbr, cts, tot_len, hpts_calling, app_limited, p_maxseg, len); 12881 if (SEQ_LT(tp->snd_nxt, tp->snd_max)) { 12882 /* Make sure snd_nxt is drug up */ 12883 tp->snd_nxt = tp->snd_max; 12884 } 12885 return (error); 12886 12887 send: 12888 if (doing_tlp == 0) { 12889 /* 12890 * Data not a TLP, and its not the rxt firing. If it is the 12891 * rxt firing, we want to leave the tlp_in_progress flag on 12892 * so we don't send another TLP. It has to be a rack timer 12893 * or normal send (response to acked data) to clear the tlp 12894 * in progress flag. 12895 */ 12896 bbr->rc_tlp_in_progress = 0; 12897 bbr->rc_tlp_rtx_out = 0; 12898 } else { 12899 /* 12900 * Its a TLP. 12901 */ 12902 bbr->rc_tlp_in_progress = 1; 12903 } 12904 bbr_timer_cancel(bbr, __LINE__, cts); 12905 if (rsm == NULL) { 12906 if (sbused(sb) > 0) { 12907 /* 12908 * This is sub-optimal. We only send a stand alone 12909 * FIN on its own segment. 12910 */ 12911 if (flags & TH_FIN) { 12912 flags &= ~TH_FIN; 12913 if ((len == 0) && ((tp->t_flags & TF_ACKNOW) == 0)) { 12914 /* Lets not send this */ 12915 slot = 0; 12916 goto just_return; 12917 } 12918 } 12919 } 12920 } else { 12921 /* 12922 * We do *not* send a FIN on a retransmit if it has data. 12923 * The if clause here where len > 1 should never come true. 12924 */ 12925 if ((len > 0) && 12926 (((rsm->r_flags & BBR_HAS_FIN) == 0) && 12927 (flags & TH_FIN))) { 12928 flags &= ~TH_FIN; 12929 len--; 12930 } 12931 } 12932 SOCKBUF_LOCK_ASSERT(sb); 12933 if (len > 0) { 12934 if ((tp->snd_una == tp->snd_max) && 12935 (bbr_calc_time(cts, bbr->r_ctl.rc_went_idle_time) >= bbr_rtt_probe_time)) { 12936 /* 12937 * This qualifies as a RTT_PROBE session since we 12938 * drop the data outstanding to nothing and waited 12939 * more than bbr_rtt_probe_time. 12940 */ 12941 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_WASIDLE, 0); 12942 bbr_set_reduced_rtt(bbr, cts, __LINE__); 12943 } 12944 if (len >= maxseg) 12945 tp->t_flags2 |= TF2_PLPMTU_MAXSEGSNT; 12946 else 12947 tp->t_flags2 &= ~TF2_PLPMTU_MAXSEGSNT; 12948 } 12949 /* 12950 * Before ESTABLISHED, force sending of initial options unless TCP 12951 * set not to do any options. NOTE: we assume that the IP/TCP header 12952 * plus TCP options always fit in a single mbuf, leaving room for a 12953 * maximum link header, i.e. max_linkhdr + sizeof (struct tcpiphdr) 12954 * + optlen <= MCLBYTES 12955 */ 12956 optlen = 0; 12957 #ifdef INET6 12958 if (isipv6) 12959 hdrlen = sizeof(struct ip6_hdr) + sizeof(struct tcphdr); 12960 else 12961 #endif 12962 hdrlen = sizeof(struct tcpiphdr); 12963 12964 /* 12965 * Compute options for segment. We only have to care about SYN and 12966 * established connection segments. Options for SYN-ACK segments 12967 * are handled in TCP syncache. 12968 */ 12969 to.to_flags = 0; 12970 local_options = 0; 12971 if ((tp->t_flags & TF_NOOPT) == 0) { 12972 /* Maximum segment size. */ 12973 if (flags & TH_SYN) { 12974 to.to_mss = tcp_mssopt(&inp->inp_inc); 12975 #ifdef NETFLIX_TCPOUDP 12976 if (tp->t_port) 12977 to.to_mss -= V_tcp_udp_tunneling_overhead; 12978 #endif 12979 to.to_flags |= TOF_MSS; 12980 /* 12981 * On SYN or SYN|ACK transmits on TFO connections, 12982 * only include the TFO option if it is not a 12983 * retransmit, as the presence of the TFO option may 12984 * have caused the original SYN or SYN|ACK to have 12985 * been dropped by a middlebox. 12986 */ 12987 if (IS_FASTOPEN(tp->t_flags) && 12988 (tp->t_rxtshift == 0)) { 12989 if (tp->t_state == TCPS_SYN_RECEIVED) { 12990 to.to_tfo_len = TCP_FASTOPEN_COOKIE_LEN; 12991 to.to_tfo_cookie = 12992 (u_int8_t *)&tp->t_tfo_cookie.server; 12993 to.to_flags |= TOF_FASTOPEN; 12994 wanted_cookie = 1; 12995 } else if (tp->t_state == TCPS_SYN_SENT) { 12996 to.to_tfo_len = 12997 tp->t_tfo_client_cookie_len; 12998 to.to_tfo_cookie = 12999 tp->t_tfo_cookie.client; 13000 to.to_flags |= TOF_FASTOPEN; 13001 wanted_cookie = 1; 13002 } 13003 } 13004 } 13005 /* Window scaling. */ 13006 if ((flags & TH_SYN) && (tp->t_flags & TF_REQ_SCALE)) { 13007 to.to_wscale = tp->request_r_scale; 13008 to.to_flags |= TOF_SCALE; 13009 } 13010 /* Timestamps. */ 13011 if ((tp->t_flags & TF_RCVD_TSTMP) || 13012 ((flags & TH_SYN) && (tp->t_flags & TF_REQ_TSTMP))) { 13013 to.to_tsval = tcp_tv_to_mssectick(&bbr->rc_tv) + tp->ts_offset; 13014 to.to_tsecr = tp->ts_recent; 13015 to.to_flags |= TOF_TS; 13016 local_options += TCPOLEN_TIMESTAMP + 2; 13017 } 13018 /* Set receive buffer autosizing timestamp. */ 13019 if (tp->rfbuf_ts == 0 && 13020 (so->so_rcv.sb_flags & SB_AUTOSIZE)) 13021 tp->rfbuf_ts = tcp_tv_to_mssectick(&bbr->rc_tv); 13022 /* Selective ACK's. */ 13023 if (flags & TH_SYN) 13024 to.to_flags |= TOF_SACKPERM; 13025 else if (TCPS_HAVEESTABLISHED(tp->t_state) && 13026 tp->rcv_numsacks > 0) { 13027 to.to_flags |= TOF_SACK; 13028 to.to_nsacks = tp->rcv_numsacks; 13029 to.to_sacks = (u_char *)tp->sackblks; 13030 } 13031 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 13032 /* TCP-MD5 (RFC2385). */ 13033 if (tp->t_flags & TF_SIGNATURE) 13034 to.to_flags |= TOF_SIGNATURE; 13035 #endif /* TCP_SIGNATURE */ 13036 13037 /* Processing the options. */ 13038 hdrlen += (optlen = tcp_addoptions(&to, opt)); 13039 /* 13040 * If we wanted a TFO option to be added, but it was unable 13041 * to fit, ensure no data is sent. 13042 */ 13043 if (IS_FASTOPEN(tp->t_flags) && wanted_cookie && 13044 !(to.to_flags & TOF_FASTOPEN)) 13045 len = 0; 13046 } 13047 #ifdef NETFLIX_TCPOUDP 13048 if (tp->t_port) { 13049 if (V_tcp_udp_tunneling_port == 0) { 13050 /* The port was removed?? */ 13051 SOCKBUF_UNLOCK(&so->so_snd); 13052 return (EHOSTUNREACH); 13053 } 13054 hdrlen += sizeof(struct udphdr); 13055 } 13056 #endif 13057 #ifdef INET6 13058 if (isipv6) 13059 ipoptlen = ip6_optlen(tp->t_inpcb); 13060 else 13061 #endif 13062 if (tp->t_inpcb->inp_options) 13063 ipoptlen = tp->t_inpcb->inp_options->m_len - 13064 offsetof(struct ipoption, ipopt_list); 13065 else 13066 ipoptlen = 0; 13067 ipoptlen = 0; 13068 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 13069 ipoptlen += ipsec_optlen; 13070 #endif 13071 if (bbr->rc_last_options != local_options) { 13072 /* 13073 * Cache the options length this generally does not change 13074 * on a connection. We use this to calculate TSO. 13075 */ 13076 bbr->rc_last_options = local_options; 13077 } 13078 maxseg = tp->t_maxseg - (ipoptlen + optlen); 13079 p_maxseg = min(maxseg, pace_max_segs); 13080 /* 13081 * Adjust data length if insertion of options will bump the packet 13082 * length beyond the t_maxseg length. Clear the FIN bit because we 13083 * cut off the tail of the segment. 13084 */ 13085 if (len > maxseg) { 13086 if (len != 0 && (flags & TH_FIN)) { 13087 flags &= ~TH_FIN; 13088 } 13089 if (tso) { 13090 uint32_t moff; 13091 int32_t max_len; 13092 13093 /* extract TSO information */ 13094 if_hw_tsomax = tp->t_tsomax; 13095 if_hw_tsomaxsegcount = tp->t_tsomaxsegcount; 13096 if_hw_tsomaxsegsize = tp->t_tsomaxsegsize; 13097 KASSERT(ipoptlen == 0, 13098 ("%s: TSO can't do IP options", __func__)); 13099 13100 /* 13101 * Check if we should limit by maximum payload 13102 * length: 13103 */ 13104 if (if_hw_tsomax != 0) { 13105 /* compute maximum TSO length */ 13106 max_len = (if_hw_tsomax - hdrlen - 13107 max_linkhdr); 13108 if (max_len <= 0) { 13109 len = 0; 13110 } else if (len > max_len) { 13111 len = max_len; 13112 } 13113 } 13114 /* 13115 * Prevent the last segment from being fractional 13116 * unless the send sockbuf can be emptied: 13117 */ 13118 if ((sb_offset + len) < sbavail(sb)) { 13119 moff = len % (uint32_t)maxseg; 13120 if (moff != 0) { 13121 len -= moff; 13122 } 13123 } 13124 /* 13125 * In case there are too many small fragments don't 13126 * use TSO: 13127 */ 13128 if (len <= maxseg) { 13129 len = maxseg; 13130 tso = 0; 13131 } 13132 } else { 13133 /* Not doing TSO */ 13134 if (optlen + ipoptlen >= tp->t_maxseg) { 13135 /* 13136 * Since we don't have enough space to put 13137 * the IP header chain and the TCP header in 13138 * one packet as required by RFC 7112, don't 13139 * send it. Also ensure that at least one 13140 * byte of the payload can be put into the 13141 * TCP segment. 13142 */ 13143 SOCKBUF_UNLOCK(&so->so_snd); 13144 error = EMSGSIZE; 13145 sack_rxmit = 0; 13146 goto out; 13147 } 13148 len = maxseg; 13149 } 13150 } else { 13151 /* Not doing TSO */ 13152 if_hw_tsomaxsegcount = 0; 13153 tso = 0; 13154 } 13155 KASSERT(len + hdrlen + ipoptlen <= IP_MAXPACKET, 13156 ("%s: len > IP_MAXPACKET", __func__)); 13157 #ifdef DIAGNOSTIC 13158 #ifdef INET6 13159 if (max_linkhdr + hdrlen > MCLBYTES) 13160 #else 13161 if (max_linkhdr + hdrlen > MHLEN) 13162 #endif 13163 panic("tcphdr too big"); 13164 #endif 13165 /* 13166 * This KASSERT is here to catch edge cases at a well defined place. 13167 * Before, those had triggered (random) panic conditions further 13168 * down. 13169 */ 13170 #ifdef BBR_INVARIANTS 13171 if (sack_rxmit) { 13172 if (SEQ_LT(rsm->r_start, tp->snd_una)) { 13173 panic("RSM:%p TP:%p bbr:%p start:%u is < snd_una:%u", 13174 rsm, tp, bbr, rsm->r_start, tp->snd_una); 13175 } 13176 } 13177 #endif 13178 KASSERT(len >= 0, ("[%s:%d]: len < 0", __func__, __LINE__)); 13179 if ((len == 0) && 13180 (flags & TH_FIN) && 13181 (sbused(sb))) { 13182 /* 13183 * We have outstanding data, don't send a fin by itself!. 13184 */ 13185 slot = 0; 13186 goto just_return; 13187 } 13188 /* 13189 * Grab a header mbuf, attaching a copy of data to be transmitted, 13190 * and initialize the header from the template for sends on this 13191 * connection. 13192 */ 13193 if (len) { 13194 uint32_t moff; 13195 uint32_t orig_len; 13196 13197 /* 13198 * We place a limit on sending with hptsi. 13199 */ 13200 if ((rsm == NULL) && len > pace_max_segs) 13201 len = pace_max_segs; 13202 if (len <= maxseg) 13203 tso = 0; 13204 #ifdef INET6 13205 if (MHLEN < hdrlen + max_linkhdr) 13206 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); 13207 else 13208 #endif 13209 m = m_gethdr(M_NOWAIT, MT_DATA); 13210 13211 if (m == NULL) { 13212 BBR_STAT_INC(bbr_failed_mbuf_aloc); 13213 bbr_log_enobuf_jmp(bbr, len, cts, __LINE__, len, 0, 0); 13214 SOCKBUF_UNLOCK(sb); 13215 error = ENOBUFS; 13216 sack_rxmit = 0; 13217 goto out; 13218 } 13219 m->m_data += max_linkhdr; 13220 m->m_len = hdrlen; 13221 /* 13222 * Start the m_copy functions from the closest mbuf to the 13223 * sb_offset in the socket buffer chain. 13224 */ 13225 if ((sb_offset > sbavail(sb)) || ((len + sb_offset) > sbavail(sb))) { 13226 #ifdef BBR_INVARIANTS 13227 if ((len + sb_offset) > (sbavail(sb) + ((flags & (TH_FIN | TH_SYN)) ? 1 : 0))) 13228 panic("tp:%p bbr:%p len:%u sb_offset:%u sbavail:%u rsm:%p %u:%u:%u", 13229 tp, bbr, len, sb_offset, sbavail(sb), rsm, 13230 doing_retran_from, 13231 picked_up_retran, 13232 doing_tlp); 13233 13234 #endif 13235 /* 13236 * In this messed up situation we have two choices, 13237 * a) pretend the send worked, and just start timers 13238 * and what not (not good since that may lead us 13239 * back here a lot). <or> b) Send the lowest segment 13240 * in the map. <or> c) Drop the connection. Lets do 13241 * <b> which if it continues to happen will lead to 13242 * <c> via timeouts. 13243 */ 13244 BBR_STAT_INC(bbr_offset_recovery); 13245 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map); 13246 sb_offset = 0; 13247 if (rsm == NULL) { 13248 sack_rxmit = 0; 13249 len = sbavail(sb); 13250 } else { 13251 sack_rxmit = 1; 13252 if (rsm->r_start != tp->snd_una) { 13253 /* 13254 * Things are really messed up, <c> 13255 * is the only thing to do. 13256 */ 13257 BBR_STAT_INC(bbr_offset_drop); 13258 tcp_set_inp_to_drop(inp, EFAULT); 13259 SOCKBUF_UNLOCK(sb); 13260 (void)m_free(m); 13261 return (0); 13262 } 13263 len = rsm->r_end - rsm->r_start; 13264 } 13265 if (len > sbavail(sb)) 13266 len = sbavail(sb); 13267 if (len > maxseg) 13268 len = maxseg; 13269 } 13270 mb = sbsndptr_noadv(sb, sb_offset, &moff); 13271 if (len <= MHLEN - hdrlen - max_linkhdr && !hw_tls) { 13272 m_copydata(mb, moff, (int)len, 13273 mtod(m, caddr_t)+hdrlen); 13274 if (rsm == NULL) 13275 sbsndptr_adv(sb, mb, len); 13276 m->m_len += len; 13277 } else { 13278 struct sockbuf *msb; 13279 13280 if (rsm) 13281 msb = NULL; 13282 else 13283 msb = sb; 13284 #ifdef BBR_INVARIANTS 13285 if ((len + moff) > (sbavail(sb) + ((flags & (TH_FIN | TH_SYN)) ? 1 : 0))) { 13286 if (rsm) { 13287 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 ", 13288 tp, bbr, len, moff, 13289 sbavail(sb), rsm, 13290 tp->snd_una, rsm->r_flags, rsm->r_start, 13291 doing_retran_from, 13292 picked_up_retran, 13293 doing_tlp, sack_rxmit); 13294 } else { 13295 panic("tp:%p bbr:%p len:%u moff:%u sbavail:%u sb_offset:%u snd_una:%u", 13296 tp, bbr, len, moff, sbavail(sb), sb_offset, tp->snd_una); 13297 } 13298 } 13299 #endif 13300 orig_len = len; 13301 m->m_next = tcp_m_copym( 13302 mb, moff, &len, 13303 if_hw_tsomaxsegcount, 13304 if_hw_tsomaxsegsize, msb, 13305 ((rsm == NULL) ? hw_tls : 0) 13306 #ifdef NETFLIX_COPY_ARGS 13307 , &filled_all 13308 #endif 13309 ); 13310 if (len <= maxseg) { 13311 /* 13312 * Must have ran out of mbufs for the copy 13313 * shorten it to no longer need tso. Lets 13314 * not put on sendalot since we are low on 13315 * mbufs. 13316 */ 13317 tso = 0; 13318 } 13319 if (m->m_next == NULL) { 13320 SOCKBUF_UNLOCK(sb); 13321 (void)m_free(m); 13322 error = ENOBUFS; 13323 sack_rxmit = 0; 13324 goto out; 13325 } 13326 } 13327 #ifdef BBR_INVARIANTS 13328 if (tso && len < maxseg) { 13329 panic("tp:%p tso on, but len:%d < maxseg:%d", 13330 tp, len, maxseg); 13331 } 13332 if (tso && if_hw_tsomaxsegcount) { 13333 int32_t seg_cnt = 0; 13334 struct mbuf *foo; 13335 13336 foo = m; 13337 while (foo) { 13338 seg_cnt++; 13339 foo = foo->m_next; 13340 } 13341 if (seg_cnt > if_hw_tsomaxsegcount) { 13342 panic("seg_cnt:%d > max:%d", seg_cnt, if_hw_tsomaxsegcount); 13343 } 13344 } 13345 #endif 13346 /* 13347 * If we're sending everything we've got, set PUSH. (This 13348 * will keep happy those implementations which only give 13349 * data to the user when a buffer fills or a PUSH comes in.) 13350 */ 13351 if (sb_offset + len == sbused(sb) && 13352 sbused(sb) && 13353 !(flags & TH_SYN)) { 13354 flags |= TH_PUSH; 13355 } 13356 SOCKBUF_UNLOCK(sb); 13357 } else { 13358 SOCKBUF_UNLOCK(sb); 13359 if (tp->t_flags & TF_ACKNOW) 13360 KMOD_TCPSTAT_INC(tcps_sndacks); 13361 else if (flags & (TH_SYN | TH_FIN | TH_RST)) 13362 KMOD_TCPSTAT_INC(tcps_sndctrl); 13363 else 13364 KMOD_TCPSTAT_INC(tcps_sndwinup); 13365 13366 m = m_gethdr(M_NOWAIT, MT_DATA); 13367 if (m == NULL) { 13368 BBR_STAT_INC(bbr_failed_mbuf_aloc); 13369 bbr_log_enobuf_jmp(bbr, len, cts, __LINE__, len, 0, 0); 13370 error = ENOBUFS; 13371 /* Fudge the send time since we could not send */ 13372 sack_rxmit = 0; 13373 goto out; 13374 } 13375 #ifdef INET6 13376 if (isipv6 && (MHLEN < hdrlen + max_linkhdr) && 13377 MHLEN >= hdrlen) { 13378 M_ALIGN(m, hdrlen); 13379 } else 13380 #endif 13381 m->m_data += max_linkhdr; 13382 m->m_len = hdrlen; 13383 } 13384 SOCKBUF_UNLOCK_ASSERT(sb); 13385 m->m_pkthdr.rcvif = (struct ifnet *)0; 13386 #ifdef MAC 13387 mac_inpcb_create_mbuf(inp, m); 13388 #endif 13389 #ifdef INET6 13390 if (isipv6) { 13391 ip6 = mtod(m, struct ip6_hdr *); 13392 #ifdef NETFLIX_TCPOUDP 13393 if (tp->t_port) { 13394 udp = (struct udphdr *)((caddr_t)ip6 + ipoptlen + sizeof(struct ip6_hdr)); 13395 udp->uh_sport = htons(V_tcp_udp_tunneling_port); 13396 udp->uh_dport = tp->t_port; 13397 ulen = hdrlen + len - sizeof(struct ip6_hdr); 13398 udp->uh_ulen = htons(ulen); 13399 th = (struct tcphdr *)(udp + 1); 13400 } else { 13401 #endif 13402 th = (struct tcphdr *)(ip6 + 1); 13403 13404 #ifdef NETFLIX_TCPOUDP 13405 } 13406 #endif 13407 tcpip_fillheaders(inp, 13408 #ifdef NETFLIX_TCPOUDP 13409 tp->t_port, 13410 #endif 13411 ip6, th); 13412 } else 13413 #endif /* INET6 */ 13414 { 13415 ip = mtod(m, struct ip *); 13416 #ifdef TCPDEBUG 13417 ipov = (struct ipovly *)ip; 13418 #endif 13419 #ifdef NETFLIX_TCPOUDP 13420 if (tp->t_port) { 13421 udp = (struct udphdr *)((caddr_t)ip + ipoptlen + sizeof(struct ip)); 13422 udp->uh_sport = htons(V_tcp_udp_tunneling_port); 13423 udp->uh_dport = tp->t_port; 13424 ulen = hdrlen + len - sizeof(struct ip); 13425 udp->uh_ulen = htons(ulen); 13426 th = (struct tcphdr *)(udp + 1); 13427 } else 13428 #endif 13429 th = (struct tcphdr *)(ip + 1); 13430 tcpip_fillheaders(inp, 13431 #ifdef NETFLIX_TCPOUDP 13432 tp->t_port, 13433 #endif 13434 ip, th); 13435 } 13436 /* 13437 * If we are doing retransmissions, then snd_nxt will not reflect 13438 * the first unsent octet. For ACK only packets, we do not want the 13439 * sequence number of the retransmitted packet, we want the sequence 13440 * number of the next unsent octet. So, if there is no data (and no 13441 * SYN or FIN), use snd_max instead of snd_nxt when filling in 13442 * ti_seq. But if we are in persist state, snd_max might reflect 13443 * one byte beyond the right edge of the window, so use snd_nxt in 13444 * that case, since we know we aren't doing a retransmission. 13445 * (retransmit and persist are mutually exclusive...) 13446 */ 13447 if (sack_rxmit == 0) { 13448 if (len && ((flags & (TH_FIN | TH_SYN | TH_RST)) == 0)) { 13449 /* New data (including new persists) */ 13450 th->th_seq = htonl(tp->snd_max); 13451 bbr_seq = tp->snd_max; 13452 } else if (flags & TH_SYN) { 13453 /* Syn's always send from iss */ 13454 th->th_seq = htonl(tp->iss); 13455 bbr_seq = tp->iss; 13456 } else if (flags & TH_FIN) { 13457 if (flags & TH_FIN && tp->t_flags & TF_SENTFIN) { 13458 /* 13459 * If we sent the fin already its 1 minus 13460 * snd_max 13461 */ 13462 th->th_seq = (htonl(tp->snd_max - 1)); 13463 bbr_seq = (tp->snd_max - 1); 13464 } else { 13465 /* First time FIN use snd_max */ 13466 th->th_seq = htonl(tp->snd_max); 13467 bbr_seq = tp->snd_max; 13468 } 13469 } else if (flags & TH_RST) { 13470 /* 13471 * For a Reset send the last cum ack in sequence 13472 * (this like any other choice may still generate a 13473 * challenge ack, if a ack-update packet is in 13474 * flight). 13475 */ 13476 th->th_seq = htonl(tp->snd_una); 13477 bbr_seq = tp->snd_una; 13478 } else { 13479 /* 13480 * len == 0 and not persist we use snd_max, sending 13481 * an ack unless we have sent the fin then its 1 13482 * minus. 13483 */ 13484 /* 13485 * XXXRRS Question if we are in persists and we have 13486 * nothing outstanding to send and we have not sent 13487 * a FIN, we will send an ACK. In such a case it 13488 * might be better to send (tp->snd_una - 1) which 13489 * would force the peer to ack. 13490 */ 13491 if (tp->t_flags & TF_SENTFIN) { 13492 th->th_seq = htonl(tp->snd_max - 1); 13493 bbr_seq = (tp->snd_max - 1); 13494 } else { 13495 th->th_seq = htonl(tp->snd_max); 13496 bbr_seq = tp->snd_max; 13497 } 13498 } 13499 } else { 13500 /* All retransmits use the rsm to guide the send */ 13501 th->th_seq = htonl(rsm->r_start); 13502 bbr_seq = rsm->r_start; 13503 } 13504 th->th_ack = htonl(tp->rcv_nxt); 13505 if (optlen) { 13506 bcopy(opt, th + 1, optlen); 13507 th->th_off = (sizeof(struct tcphdr) + optlen) >> 2; 13508 } 13509 th->th_flags = flags; 13510 /* 13511 * Calculate receive window. Don't shrink window, but avoid silly 13512 * window syndrome. 13513 */ 13514 if ((flags & TH_RST) || ((recwin < (so->so_rcv.sb_hiwat / 4) && 13515 recwin < maxseg))) 13516 recwin = 0; 13517 if (SEQ_GT(tp->rcv_adv, tp->rcv_nxt) && 13518 recwin < (tp->rcv_adv - tp->rcv_nxt)) 13519 recwin = (tp->rcv_adv - tp->rcv_nxt); 13520 if (recwin > TCP_MAXWIN << tp->rcv_scale) 13521 recwin = TCP_MAXWIN << tp->rcv_scale; 13522 13523 /* 13524 * According to RFC1323 the window field in a SYN (i.e., a <SYN> or 13525 * <SYN,ACK>) segment itself is never scaled. The <SYN,ACK> case is 13526 * handled in syncache. 13527 */ 13528 if (flags & TH_SYN) 13529 th->th_win = htons((u_short) 13530 (min(sbspace(&so->so_rcv), TCP_MAXWIN))); 13531 else { 13532 /* Avoid shrinking window with window scaling. */ 13533 recwin = roundup2(recwin, 1 << tp->rcv_scale); 13534 th->th_win = htons((u_short)(recwin >> tp->rcv_scale)); 13535 } 13536 /* 13537 * Adjust the RXWIN0SENT flag - indicate that we have advertised a 0 13538 * window. This may cause the remote transmitter to stall. This 13539 * flag tells soreceive() to disable delayed acknowledgements when 13540 * draining the buffer. This can occur if the receiver is 13541 * attempting to read more data than can be buffered prior to 13542 * transmitting on the connection. 13543 */ 13544 if (th->th_win == 0) { 13545 tp->t_sndzerowin++; 13546 tp->t_flags |= TF_RXWIN0SENT; 13547 } else 13548 tp->t_flags &= ~TF_RXWIN0SENT; 13549 /* 13550 * We don't support urgent data, but drag along 13551 * the pointer in case of a stack switch. 13552 */ 13553 tp->snd_up = tp->snd_una; 13554 13555 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 13556 if (to.to_flags & TOF_SIGNATURE) { 13557 /* 13558 * Calculate MD5 signature and put it into the place 13559 * determined before. NOTE: since TCP options buffer doesn't 13560 * point into mbuf's data, calculate offset and use it. 13561 */ 13562 if (!TCPMD5_ENABLED() || TCPMD5_OUTPUT(m, th, 13563 (u_char *)(th + 1) + (to.to_signature - opt)) != 0) { 13564 /* 13565 * Do not send segment if the calculation of MD5 13566 * digest has failed. 13567 */ 13568 goto out; 13569 } 13570 } 13571 #endif 13572 13573 /* 13574 * Put TCP length in extended header, and then checksum extended 13575 * header and data. 13576 */ 13577 m->m_pkthdr.len = hdrlen + len; /* in6_cksum() need this */ 13578 #ifdef INET6 13579 if (isipv6) { 13580 /* 13581 * ip6_plen is not need to be filled now, and will be filled 13582 * in ip6_output. 13583 */ 13584 #ifdef NETFLIX_TCPOUDP 13585 if (tp->t_port) { 13586 m->m_pkthdr.csum_flags = CSUM_UDP_IPV6; 13587 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 13588 udp->uh_sum = in6_cksum_pseudo(ip6, ulen, IPPROTO_UDP, 0); 13589 th->th_sum = htons(0); 13590 UDPSTAT_INC(udps_opackets); 13591 } else { 13592 #endif 13593 csum_flags = m->m_pkthdr.csum_flags = CSUM_TCP_IPV6; 13594 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 13595 th->th_sum = in6_cksum_pseudo(ip6, sizeof(struct tcphdr) + 13596 optlen + len, IPPROTO_TCP, 0); 13597 #ifdef NETFLIX_TCPOUDP 13598 } 13599 #endif 13600 } 13601 #endif 13602 #if defined(INET6) && defined(INET) 13603 else 13604 #endif 13605 #ifdef INET 13606 { 13607 #ifdef NETFLIX_TCPOUDP 13608 if (tp->t_port) { 13609 m->m_pkthdr.csum_flags = CSUM_UDP; 13610 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 13611 udp->uh_sum = in_pseudo(ip->ip_src.s_addr, 13612 ip->ip_dst.s_addr, htons(ulen + IPPROTO_UDP)); 13613 th->th_sum = htons(0); 13614 UDPSTAT_INC(udps_opackets); 13615 } else { 13616 #endif 13617 csum_flags = m->m_pkthdr.csum_flags = CSUM_TCP; 13618 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 13619 th->th_sum = in_pseudo(ip->ip_src.s_addr, 13620 ip->ip_dst.s_addr, htons(sizeof(struct tcphdr) + 13621 IPPROTO_TCP + len + optlen)); 13622 #ifdef NETFLIX_TCPOUDP 13623 } 13624 #endif 13625 /* IP version must be set here for ipv4/ipv6 checking later */ 13626 KASSERT(ip->ip_v == IPVERSION, 13627 ("%s: IP version incorrect: %d", __func__, ip->ip_v)); 13628 } 13629 #endif 13630 13631 /* 13632 * Enable TSO and specify the size of the segments. The TCP pseudo 13633 * header checksum is always provided. XXX: Fixme: This is currently 13634 * not the case for IPv6. 13635 */ 13636 if (tso) { 13637 KASSERT(len > maxseg, 13638 ("%s: len:%d <= tso_segsz:%d", __func__, len, maxseg)); 13639 m->m_pkthdr.csum_flags |= CSUM_TSO; 13640 csum_flags |= CSUM_TSO; 13641 m->m_pkthdr.tso_segsz = maxseg; 13642 } 13643 KASSERT(len + hdrlen == m_length(m, NULL), 13644 ("%s: mbuf chain different than expected: %d + %u != %u", 13645 __func__, len, hdrlen, m_length(m, NULL))); 13646 13647 #ifdef TCP_HHOOK 13648 /* Run HHOOK_TC_ESTABLISHED_OUT helper hooks. */ 13649 hhook_run_tcp_est_out(tp, th, &to, len, tso); 13650 #endif 13651 #ifdef TCPDEBUG 13652 /* 13653 * Trace. 13654 */ 13655 if (so->so_options & SO_DEBUG) { 13656 u_short save = 0; 13657 13658 #ifdef INET6 13659 if (!isipv6) 13660 #endif 13661 { 13662 save = ipov->ih_len; 13663 ipov->ih_len = htons(m->m_pkthdr.len /* - hdrlen + 13664 * (th->th_off << 2) */ ); 13665 } 13666 tcp_trace(TA_OUTPUT, tp->t_state, tp, mtod(m, void *), th, 0); 13667 #ifdef INET6 13668 if (!isipv6) 13669 #endif 13670 ipov->ih_len = save; 13671 } 13672 #endif /* TCPDEBUG */ 13673 13674 /* Log to the black box */ 13675 if (tp->t_logstate != TCP_LOG_STATE_OFF) { 13676 union tcp_log_stackspecific log; 13677 13678 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts); 13679 /* Record info on type of transmission */ 13680 log.u_bbr.flex1 = bbr->r_ctl.rc_hptsi_agg_delay; 13681 log.u_bbr.flex2 = (bbr->r_recovery_bw << 3); 13682 log.u_bbr.flex3 = maxseg; 13683 log.u_bbr.flex4 = delay_calc; 13684 /* Encode filled_all into the upper flex5 bit */ 13685 log.u_bbr.flex5 = bbr->rc_past_init_win; 13686 log.u_bbr.flex5 <<= 1; 13687 log.u_bbr.flex5 |= bbr->rc_no_pacing; 13688 log.u_bbr.flex5 <<= 29; 13689 if (filled_all) 13690 log.u_bbr.flex5 |= 0x80000000; 13691 log.u_bbr.flex5 |= tp->t_maxseg; 13692 log.u_bbr.flex6 = bbr->r_ctl.rc_pace_max_segs; 13693 log.u_bbr.flex7 = (bbr->rc_bbr_state << 8) | bbr_state_val(bbr); 13694 /* lets poke in the low and the high here for debugging */ 13695 log.u_bbr.pkts_out = bbr->rc_tp->t_maxseg; 13696 if (rsm || sack_rxmit) { 13697 if (doing_tlp) 13698 log.u_bbr.flex8 = 2; 13699 else 13700 log.u_bbr.flex8 = 1; 13701 } else { 13702 log.u_bbr.flex8 = 0; 13703 } 13704 lgb = tcp_log_event_(tp, th, &so->so_rcv, &so->so_snd, TCP_LOG_OUT, ERRNO_UNK, 13705 len, &log, false, NULL, NULL, 0, tv); 13706 } else { 13707 lgb = NULL; 13708 } 13709 /* 13710 * Fill in IP length and desired time to live and send to IP level. 13711 * There should be a better way to handle ttl and tos; we could keep 13712 * them in the template, but need a way to checksum without them. 13713 */ 13714 /* 13715 * m->m_pkthdr.len should have been set before cksum calcuration, 13716 * because in6_cksum() need it. 13717 */ 13718 #ifdef INET6 13719 if (isipv6) { 13720 /* 13721 * we separately set hoplimit for every segment, since the 13722 * user might want to change the value via setsockopt. Also, 13723 * desired default hop limit might be changed via Neighbor 13724 * Discovery. 13725 */ 13726 ip6->ip6_hlim = in6_selecthlim(inp, NULL); 13727 13728 /* 13729 * Set the packet size here for the benefit of DTrace 13730 * probes. ip6_output() will set it properly; it's supposed 13731 * to include the option header lengths as well. 13732 */ 13733 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(*ip6)); 13734 13735 if (V_path_mtu_discovery && maxseg > V_tcp_minmss) 13736 tp->t_flags2 |= TF2_PLPMTU_PMTUD; 13737 else 13738 tp->t_flags2 &= ~TF2_PLPMTU_PMTUD; 13739 13740 if (tp->t_state == TCPS_SYN_SENT) 13741 TCP_PROBE5(connect__request, NULL, tp, ip6, tp, th); 13742 13743 TCP_PROBE5(send, NULL, tp, ip6, tp, th); 13744 /* TODO: IPv6 IP6TOS_ECT bit on */ 13745 error = ip6_output(m, inp->in6p_outputopts, 13746 &inp->inp_route6, 13747 ((rsm || sack_rxmit) ? IP_NO_SND_TAG_RL : 0), 13748 NULL, NULL, inp); 13749 13750 if (error == EMSGSIZE && inp->inp_route6.ro_nh != NULL) 13751 mtu = inp->inp_route6.ro_nh->nh_mtu; 13752 } 13753 #endif /* INET6 */ 13754 #if defined(INET) && defined(INET6) 13755 else 13756 #endif 13757 #ifdef INET 13758 { 13759 ip->ip_len = htons(m->m_pkthdr.len); 13760 #ifdef INET6 13761 if (isipv6) 13762 ip->ip_ttl = in6_selecthlim(inp, NULL); 13763 #endif /* INET6 */ 13764 /* 13765 * If we do path MTU discovery, then we set DF on every 13766 * packet. This might not be the best thing to do according 13767 * to RFC3390 Section 2. However the tcp hostcache migitates 13768 * the problem so it affects only the first tcp connection 13769 * with a host. 13770 * 13771 * NB: Don't set DF on small MTU/MSS to have a safe 13772 * fallback. 13773 */ 13774 if (V_path_mtu_discovery && tp->t_maxseg > V_tcp_minmss) { 13775 tp->t_flags2 |= TF2_PLPMTU_PMTUD; 13776 if (tp->t_port == 0 || len < V_tcp_minmss) { 13777 ip->ip_off |= htons(IP_DF); 13778 } 13779 } else { 13780 tp->t_flags2 &= ~TF2_PLPMTU_PMTUD; 13781 } 13782 13783 if (tp->t_state == TCPS_SYN_SENT) 13784 TCP_PROBE5(connect__request, NULL, tp, ip, tp, th); 13785 13786 TCP_PROBE5(send, NULL, tp, ip, tp, th); 13787 13788 error = ip_output(m, inp->inp_options, &inp->inp_route, 13789 ((rsm || sack_rxmit) ? IP_NO_SND_TAG_RL : 0), 0, 13790 inp); 13791 if (error == EMSGSIZE && inp->inp_route.ro_nh != NULL) 13792 mtu = inp->inp_route.ro_nh->nh_mtu; 13793 } 13794 #endif /* INET */ 13795 out: 13796 13797 if (lgb) { 13798 lgb->tlb_errno = error; 13799 lgb = NULL; 13800 } 13801 /* 13802 * In transmit state, time the transmission and arrange for the 13803 * retransmit. In persist state, just set snd_max. 13804 */ 13805 if (error == 0) { 13806 if (TCPS_HAVEESTABLISHED(tp->t_state) && 13807 (tp->t_flags & TF_SACK_PERMIT) && 13808 tp->rcv_numsacks > 0) 13809 tcp_clean_dsack_blocks(tp); 13810 /* We sent an ack clear the bbr_segs_rcvd count */ 13811 bbr->output_error_seen = 0; 13812 bbr->oerror_cnt = 0; 13813 bbr->bbr_segs_rcvd = 0; 13814 if (len == 0) 13815 counter_u64_add(bbr_out_size[TCP_MSS_ACCT_SNDACK], 1); 13816 /* Do accounting for new sends */ 13817 if ((len > 0) && (rsm == NULL)) { 13818 int idx; 13819 if (tp->snd_una == tp->snd_max) { 13820 /* 13821 * Special case to match google, when 13822 * nothing is in flight the delivered 13823 * time does get updated to the current 13824 * time (see tcp_rate_bsd.c). 13825 */ 13826 bbr->r_ctl.rc_del_time = cts; 13827 } 13828 if (len >= maxseg) { 13829 idx = (len / maxseg) + 3; 13830 if (idx >= TCP_MSS_ACCT_ATIMER) 13831 counter_u64_add(bbr_out_size[(TCP_MSS_ACCT_ATIMER - 1)], 1); 13832 else 13833 counter_u64_add(bbr_out_size[idx], 1); 13834 } else { 13835 /* smaller than a MSS */ 13836 idx = len / (bbr_hptsi_bytes_min - bbr->rc_last_options); 13837 if (idx >= TCP_MSS_SMALL_MAX_SIZE_DIV) 13838 idx = (TCP_MSS_SMALL_MAX_SIZE_DIV - 1); 13839 counter_u64_add(bbr_out_size[(idx + TCP_MSS_SMALL_SIZE_OFF)], 1); 13840 } 13841 } 13842 } 13843 abandon = 0; 13844 /* 13845 * We must do the send accounting before we log the output, 13846 * otherwise the state of the rsm could change and we account to the 13847 * wrong bucket. 13848 */ 13849 if (len > 0) { 13850 bbr_do_send_accounting(tp, bbr, rsm, len, error); 13851 if (error == 0) { 13852 if (tp->snd_una == tp->snd_max) 13853 bbr->r_ctl.rc_tlp_rxt_last_time = cts; 13854 } 13855 } 13856 bbr_log_output(bbr, tp, &to, len, bbr_seq, (uint8_t) flags, error, 13857 cts, mb, &abandon, rsm, 0, sb); 13858 if (abandon) { 13859 /* 13860 * If bbr_log_output destroys the TCB or sees a TH_RST being 13861 * sent we should hit this condition. 13862 */ 13863 return (0); 13864 } 13865 if (bbr->rc_in_persist == 0) { 13866 /* 13867 * Advance snd_nxt over sequence space of this segment. 13868 */ 13869 if (error) 13870 /* We don't log or do anything with errors */ 13871 goto skip_upd; 13872 13873 if (tp->snd_una == tp->snd_max && 13874 (len || (flags & (TH_SYN | TH_FIN)))) { 13875 /* 13876 * Update the time we just added data since none was 13877 * outstanding. 13878 */ 13879 bbr_log_progress_event(bbr, tp, ticks, PROGRESS_START, __LINE__); 13880 bbr->rc_tp->t_acktime = ticks; 13881 } 13882 if (flags & (TH_SYN | TH_FIN) && (rsm == NULL)) { 13883 if (flags & TH_SYN) { 13884 /* 13885 * Smack the snd_max to iss + 1 13886 * if its a FO we will add len below. 13887 */ 13888 tp->snd_max = tp->iss + 1; 13889 } 13890 if ((flags & TH_FIN) && ((tp->t_flags & TF_SENTFIN) == 0)) { 13891 tp->snd_max++; 13892 tp->t_flags |= TF_SENTFIN; 13893 } 13894 } 13895 if (sack_rxmit == 0) 13896 tp->snd_max += len; 13897 skip_upd: 13898 if ((error == 0) && len) 13899 tot_len += len; 13900 } else { 13901 /* Persists case */ 13902 int32_t xlen = len; 13903 13904 if (error) 13905 goto nomore; 13906 13907 if (flags & TH_SYN) 13908 ++xlen; 13909 if ((flags & TH_FIN) && ((tp->t_flags & TF_SENTFIN) == 0)) { 13910 ++xlen; 13911 tp->t_flags |= TF_SENTFIN; 13912 } 13913 if (xlen && (tp->snd_una == tp->snd_max)) { 13914 /* 13915 * Update the time we just added data since none was 13916 * outstanding. 13917 */ 13918 bbr_log_progress_event(bbr, tp, ticks, PROGRESS_START, __LINE__); 13919 bbr->rc_tp->t_acktime = ticks; 13920 } 13921 if (sack_rxmit == 0) 13922 tp->snd_max += xlen; 13923 tot_len += (len + optlen + ipoptlen); 13924 } 13925 nomore: 13926 if (error) { 13927 /* 13928 * Failures do not advance the seq counter above. For the 13929 * case of ENOBUFS we will fall out and become ack-clocked. 13930 * capping the cwnd at the current flight. 13931 * Everything else will just have to retransmit with the timer 13932 * (no pacer). 13933 */ 13934 SOCKBUF_UNLOCK_ASSERT(sb); 13935 BBR_STAT_INC(bbr_saw_oerr); 13936 /* Clear all delay/early tracks */ 13937 bbr->r_ctl.rc_hptsi_agg_delay = 0; 13938 bbr->r_ctl.rc_agg_early = 0; 13939 bbr->r_agg_early_set = 0; 13940 bbr->output_error_seen = 1; 13941 if (bbr->oerror_cnt < 0xf) 13942 bbr->oerror_cnt++; 13943 if (bbr_max_net_error_cnt && (bbr->oerror_cnt >= bbr_max_net_error_cnt)) { 13944 /* drop the session */ 13945 tcp_set_inp_to_drop(inp, ENETDOWN); 13946 } 13947 switch (error) { 13948 case ENOBUFS: 13949 /* 13950 * Make this guy have to get ack's to send 13951 * more but lets make sure we don't 13952 * slam him below a T-O (1MSS). 13953 */ 13954 if (bbr->rc_bbr_state != BBR_STATE_PROBE_RTT) { 13955 tp->snd_cwnd = ctf_flight_size(tp, (bbr->r_ctl.rc_sacked + 13956 bbr->r_ctl.rc_lost_bytes)) - maxseg; 13957 if (tp->snd_cwnd < maxseg) 13958 tp->snd_cwnd = maxseg; 13959 } 13960 slot = (bbr_error_base_paceout + 1) << bbr->oerror_cnt; 13961 BBR_STAT_INC(bbr_saw_enobuf); 13962 if (bbr->bbr_hdrw_pacing) 13963 counter_u64_add(bbr_hdwr_pacing_enobuf, 1); 13964 else 13965 counter_u64_add(bbr_nohdwr_pacing_enobuf, 1); 13966 /* 13967 * Here even in the enobuf's case we want to do our 13968 * state update. The reason being we may have been 13969 * called by the input function. If so we have had 13970 * things change. 13971 */ 13972 error = 0; 13973 goto enobufs; 13974 case EMSGSIZE: 13975 /* 13976 * For some reason the interface we used initially 13977 * to send segments changed to another or lowered 13978 * its MTU. If TSO was active we either got an 13979 * interface without TSO capabilits or TSO was 13980 * turned off. If we obtained mtu from ip_output() 13981 * then update it and try again. 13982 */ 13983 /* Turn on tracing (or try to) */ 13984 { 13985 int old_maxseg; 13986 13987 old_maxseg = tp->t_maxseg; 13988 BBR_STAT_INC(bbr_saw_emsgsiz); 13989 bbr_log_msgsize_fail(bbr, tp, len, maxseg, mtu, csum_flags, tso, cts); 13990 if (mtu != 0) 13991 tcp_mss_update(tp, -1, mtu, NULL, NULL); 13992 if (old_maxseg <= tp->t_maxseg) { 13993 /* Huh it did not shrink? */ 13994 tp->t_maxseg = old_maxseg - 40; 13995 bbr_log_msgsize_fail(bbr, tp, len, maxseg, mtu, 0, tso, cts); 13996 } 13997 /* 13998 * Nuke all other things that can interfere 13999 * with slot 14000 */ 14001 if ((tot_len + len) && (len >= tp->t_maxseg)) { 14002 slot = bbr_get_pacing_delay(bbr, 14003 bbr->r_ctl.rc_bbr_hptsi_gain, 14004 (tot_len + len), cts, 0); 14005 if (slot < bbr_error_base_paceout) 14006 slot = (bbr_error_base_paceout + 2) << bbr->oerror_cnt; 14007 } else 14008 slot = (bbr_error_base_paceout + 2) << bbr->oerror_cnt; 14009 bbr->rc_output_starts_timer = 1; 14010 bbr_start_hpts_timer(bbr, tp, cts, 10, slot, 14011 tot_len); 14012 return (error); 14013 } 14014 case EPERM: 14015 tp->t_softerror = error; 14016 /* Fall through */ 14017 case EHOSTDOWN: 14018 case EHOSTUNREACH: 14019 case ENETDOWN: 14020 case ENETUNREACH: 14021 if (TCPS_HAVERCVDSYN(tp->t_state)) { 14022 tp->t_softerror = error; 14023 } 14024 /* FALLTHROUGH */ 14025 default: 14026 slot = (bbr_error_base_paceout + 3) << bbr->oerror_cnt; 14027 bbr->rc_output_starts_timer = 1; 14028 bbr_start_hpts_timer(bbr, tp, cts, 11, slot, 0); 14029 return (error); 14030 } 14031 #ifdef STATS 14032 } else if (((tp->t_flags & TF_GPUTINPROG) == 0) && 14033 len && 14034 (rsm == NULL) && 14035 (bbr->rc_in_persist == 0)) { 14036 tp->gput_seq = bbr_seq; 14037 tp->gput_ack = bbr_seq + 14038 min(sbavail(&so->so_snd) - sb_offset, sendwin); 14039 tp->gput_ts = cts; 14040 tp->t_flags |= TF_GPUTINPROG; 14041 #endif 14042 } 14043 KMOD_TCPSTAT_INC(tcps_sndtotal); 14044 if ((bbr->bbr_hdw_pace_ena) && 14045 (bbr->bbr_attempt_hdwr_pace == 0) && 14046 (bbr->rc_past_init_win) && 14047 (bbr->rc_bbr_state != BBR_STATE_STARTUP) && 14048 (get_filter_value(&bbr->r_ctl.rc_delrate)) && 14049 (inp->inp_route.ro_nh && 14050 inp->inp_route.ro_nh->nh_ifp)) { 14051 /* 14052 * We are past the initial window and 14053 * have at least one measurement so we 14054 * could use hardware pacing if its available. 14055 * We have an interface and we have not attempted 14056 * to setup hardware pacing, lets try to now. 14057 */ 14058 uint64_t rate_wanted; 14059 int err = 0; 14060 14061 rate_wanted = bbr_get_hardware_rate(bbr); 14062 bbr->bbr_attempt_hdwr_pace = 1; 14063 bbr->r_ctl.crte = tcp_set_pacing_rate(bbr->rc_tp, 14064 inp->inp_route.ro_nh->nh_ifp, 14065 rate_wanted, 14066 (RS_PACING_GEQ|RS_PACING_SUB_OK), 14067 &err); 14068 if (bbr->r_ctl.crte) { 14069 bbr_type_log_hdwr_pacing(bbr, 14070 bbr->r_ctl.crte->ptbl->rs_ifp, 14071 rate_wanted, 14072 bbr->r_ctl.crte->rate, 14073 __LINE__, cts, err); 14074 BBR_STAT_INC(bbr_hdwr_rl_add_ok); 14075 counter_u64_add(bbr_flows_nohdwr_pacing, -1); 14076 counter_u64_add(bbr_flows_whdwr_pacing, 1); 14077 bbr->bbr_hdrw_pacing = 1; 14078 /* Now what is our gain status? */ 14079 if (bbr->r_ctl.crte->rate < rate_wanted) { 14080 /* We have a problem */ 14081 bbr_setup_less_of_rate(bbr, cts, 14082 bbr->r_ctl.crte->rate, rate_wanted); 14083 } else { 14084 /* We are good */ 14085 bbr->gain_is_limited = 0; 14086 bbr->skip_gain = 0; 14087 } 14088 tcp_bbr_tso_size_check(bbr, cts); 14089 } else { 14090 bbr_type_log_hdwr_pacing(bbr, 14091 inp->inp_route.ro_nh->nh_ifp, 14092 rate_wanted, 14093 0, 14094 __LINE__, cts, err); 14095 BBR_STAT_INC(bbr_hdwr_rl_add_fail); 14096 } 14097 } 14098 if (bbr->bbr_hdrw_pacing) { 14099 /* 14100 * Worry about cases where the route 14101 * changes or something happened that we 14102 * lost our hardware pacing possibly during 14103 * the last ip_output call. 14104 */ 14105 if (inp->inp_snd_tag == NULL) { 14106 /* A change during ip output disabled hw pacing? */ 14107 bbr->bbr_hdrw_pacing = 0; 14108 } else if ((inp->inp_route.ro_nh == NULL) || 14109 (inp->inp_route.ro_nh->nh_ifp != inp->inp_snd_tag->ifp)) { 14110 /* 14111 * We had an interface or route change, 14112 * detach from the current hdwr pacing 14113 * and setup to re-attempt next go 14114 * round. 14115 */ 14116 bbr->bbr_hdrw_pacing = 0; 14117 bbr->bbr_attempt_hdwr_pace = 0; 14118 tcp_rel_pacing_rate(bbr->r_ctl.crte, bbr->rc_tp); 14119 tcp_bbr_tso_size_check(bbr, cts); 14120 } 14121 } 14122 /* 14123 * Data sent (as far as we can tell). If this advertises a larger 14124 * window than any other segment, then remember the size of the 14125 * advertised window. Any pending ACK has now been sent. 14126 */ 14127 if (SEQ_GT(tp->rcv_nxt + recwin, tp->rcv_adv)) 14128 tp->rcv_adv = tp->rcv_nxt + recwin; 14129 14130 tp->last_ack_sent = tp->rcv_nxt; 14131 if ((error == 0) && 14132 (bbr->r_ctl.rc_pace_max_segs > tp->t_maxseg) && 14133 (doing_tlp == 0) && 14134 (tso == 0) && 14135 (len > 0) && 14136 ((flags & TH_RST) == 0) && 14137 ((flags & TH_SYN) == 0) && 14138 (IN_RECOVERY(tp->t_flags) == 0) && 14139 (bbr->rc_in_persist == 0) && 14140 (tot_len < bbr->r_ctl.rc_pace_max_segs)) { 14141 /* 14142 * For non-tso we need to goto again until we have sent out 14143 * enough data to match what we are hptsi out every hptsi 14144 * interval. 14145 */ 14146 if (SEQ_LT(tp->snd_nxt, tp->snd_max)) { 14147 /* Make sure snd_nxt is drug up */ 14148 tp->snd_nxt = tp->snd_max; 14149 } 14150 if (rsm != NULL) { 14151 rsm = NULL; 14152 goto skip_again; 14153 } 14154 rsm = NULL; 14155 sack_rxmit = 0; 14156 tp->t_flags &= ~(TF_ACKNOW | TF_DELACK); 14157 goto again; 14158 } 14159 skip_again: 14160 if ((error == 0) && (flags & TH_FIN)) 14161 tcp_log_end_status(tp, TCP_EI_STATUS_SERVER_FIN); 14162 if ((error == 0) && (flags & TH_RST)) 14163 tcp_log_end_status(tp, TCP_EI_STATUS_SERVER_RST); 14164 if (((flags & (TH_RST | TH_SYN | TH_FIN)) == 0) && tot_len) { 14165 /* 14166 * Calculate/Re-Calculate the hptsi slot in usecs based on 14167 * what we have sent so far 14168 */ 14169 slot = bbr_get_pacing_delay(bbr, bbr->r_ctl.rc_bbr_hptsi_gain, tot_len, cts, 0); 14170 if (bbr->rc_no_pacing) 14171 slot = 0; 14172 } 14173 tp->t_flags &= ~(TF_ACKNOW | TF_DELACK); 14174 enobufs: 14175 if (bbr->rc_use_google == 0) 14176 bbr_check_bbr_for_state(bbr, cts, __LINE__, 0); 14177 bbr_cwnd_limiting(tp, bbr, ctf_flight_size(tp, (bbr->r_ctl.rc_sacked + 14178 bbr->r_ctl.rc_lost_bytes))); 14179 bbr->rc_output_starts_timer = 1; 14180 if (bbr->bbr_use_rack_cheat && 14181 (more_to_rxt || 14182 ((bbr->r_ctl.rc_resend = bbr_check_recovery_mode(tp, bbr, cts)) != NULL))) { 14183 /* Rack cheats and shotguns out all rxt's 1ms apart */ 14184 if (slot > 1000) 14185 slot = 1000; 14186 } 14187 if (bbr->bbr_hdrw_pacing && (bbr->hw_pacing_set == 0)) { 14188 /* 14189 * We don't change the tso size until some number of sends 14190 * to give the hardware commands time to get down 14191 * to the interface. 14192 */ 14193 bbr->r_ctl.bbr_hdwr_cnt_noset_snt++; 14194 if (bbr->r_ctl.bbr_hdwr_cnt_noset_snt >= bbr_hdwr_pacing_delay_cnt) { 14195 bbr->hw_pacing_set = 1; 14196 tcp_bbr_tso_size_check(bbr, cts); 14197 } 14198 } 14199 bbr_start_hpts_timer(bbr, tp, cts, 12, slot, tot_len); 14200 if (SEQ_LT(tp->snd_nxt, tp->snd_max)) { 14201 /* Make sure snd_nxt is drug up */ 14202 tp->snd_nxt = tp->snd_max; 14203 } 14204 return (error); 14205 14206 } 14207 14208 /* 14209 * See bbr_output_wtime() for return values. 14210 */ 14211 static int 14212 bbr_output(struct tcpcb *tp) 14213 { 14214 int32_t ret; 14215 struct timeval tv; 14216 struct tcp_bbr *bbr; 14217 14218 NET_EPOCH_ASSERT(); 14219 14220 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 14221 INP_WLOCK_ASSERT(tp->t_inpcb); 14222 (void)tcp_get_usecs(&tv); 14223 ret = bbr_output_wtime(tp, &tv); 14224 return (ret); 14225 } 14226 14227 static void 14228 bbr_mtu_chg(struct tcpcb *tp) 14229 { 14230 struct tcp_bbr *bbr; 14231 struct bbr_sendmap *rsm, *frsm = NULL; 14232 uint32_t maxseg; 14233 14234 /* 14235 * The MTU has changed. a) Clear the sack filter. b) Mark everything 14236 * over the current size as SACK_PASS so a retransmit will occur. 14237 */ 14238 14239 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 14240 maxseg = tp->t_maxseg - bbr->rc_last_options; 14241 sack_filter_clear(&bbr->r_ctl.bbr_sf, tp->snd_una); 14242 TAILQ_FOREACH(rsm, &bbr->r_ctl.rc_map, r_next) { 14243 /* Don't mess with ones acked (by sack?) */ 14244 if (rsm->r_flags & BBR_ACKED) 14245 continue; 14246 if ((rsm->r_end - rsm->r_start) > maxseg) { 14247 /* 14248 * We mark sack-passed on all the previous large 14249 * sends we did. This will force them to retransmit. 14250 */ 14251 rsm->r_flags |= BBR_SACK_PASSED; 14252 if (((rsm->r_flags & BBR_MARKED_LOST) == 0) && 14253 bbr_is_lost(bbr, rsm, bbr->r_ctl.rc_rcvtime)) { 14254 bbr->r_ctl.rc_lost_bytes += rsm->r_end - rsm->r_start; 14255 bbr->r_ctl.rc_lost += rsm->r_end - rsm->r_start; 14256 rsm->r_flags |= BBR_MARKED_LOST; 14257 } 14258 if (frsm == NULL) 14259 frsm = rsm; 14260 } 14261 } 14262 if (frsm) { 14263 bbr->r_ctl.rc_resend = frsm; 14264 } 14265 } 14266 14267 /* 14268 * bbr_ctloutput() must drop the inpcb lock before performing copyin on 14269 * socket option arguments. When it re-acquires the lock after the copy, it 14270 * has to revalidate that the connection is still valid for the socket 14271 * option. 14272 */ 14273 static int 14274 bbr_set_sockopt(struct socket *so, struct sockopt *sopt, 14275 struct inpcb *inp, struct tcpcb *tp, struct tcp_bbr *bbr) 14276 { 14277 struct epoch_tracker et; 14278 int32_t error = 0, optval; 14279 14280 switch (sopt->sopt_name) { 14281 case TCP_RACK_PACE_MAX_SEG: 14282 case TCP_RACK_MIN_TO: 14283 case TCP_RACK_REORD_THRESH: 14284 case TCP_RACK_REORD_FADE: 14285 case TCP_RACK_TLP_THRESH: 14286 case TCP_RACK_PKT_DELAY: 14287 case TCP_BBR_ALGORITHM: 14288 case TCP_BBR_TSLIMITS: 14289 case TCP_BBR_IWINTSO: 14290 case TCP_BBR_RECFORCE: 14291 case TCP_BBR_STARTUP_PG: 14292 case TCP_BBR_DRAIN_PG: 14293 case TCP_BBR_RWND_IS_APP: 14294 case TCP_BBR_PROBE_RTT_INT: 14295 case TCP_BBR_PROBE_RTT_GAIN: 14296 case TCP_BBR_PROBE_RTT_LEN: 14297 case TCP_BBR_STARTUP_LOSS_EXIT: 14298 case TCP_BBR_USEDEL_RATE: 14299 case TCP_BBR_MIN_RTO: 14300 case TCP_BBR_MAX_RTO: 14301 case TCP_BBR_PACE_PER_SEC: 14302 case TCP_DELACK: 14303 case TCP_BBR_PACE_DEL_TAR: 14304 case TCP_BBR_SEND_IWND_IN_TSO: 14305 case TCP_BBR_EXTRA_STATE: 14306 case TCP_BBR_UTTER_MAX_TSO: 14307 case TCP_BBR_MIN_TOPACEOUT: 14308 case TCP_BBR_FLOOR_MIN_TSO: 14309 case TCP_BBR_TSTMP_RAISES: 14310 case TCP_BBR_POLICER_DETECT: 14311 case TCP_BBR_USE_RACK_CHEAT: 14312 case TCP_DATA_AFTER_CLOSE: 14313 case TCP_BBR_HDWR_PACE: 14314 case TCP_BBR_PACE_SEG_MAX: 14315 case TCP_BBR_PACE_SEG_MIN: 14316 case TCP_BBR_PACE_CROSS: 14317 case TCP_BBR_PACE_OH: 14318 #ifdef NETFLIX_PEAKRATE 14319 case TCP_MAXPEAKRATE: 14320 #endif 14321 case TCP_BBR_TMR_PACE_OH: 14322 case TCP_BBR_RACK_RTT_USE: 14323 case TCP_BBR_RETRAN_WTSO: 14324 break; 14325 default: 14326 return (tcp_default_ctloutput(so, sopt, inp, tp)); 14327 break; 14328 } 14329 INP_WUNLOCK(inp); 14330 error = sooptcopyin(sopt, &optval, sizeof(optval), sizeof(optval)); 14331 if (error) 14332 return (error); 14333 INP_WLOCK(inp); 14334 if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) { 14335 INP_WUNLOCK(inp); 14336 return (ECONNRESET); 14337 } 14338 tp = intotcpcb(inp); 14339 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 14340 switch (sopt->sopt_name) { 14341 case TCP_BBR_PACE_PER_SEC: 14342 BBR_OPTS_INC(tcp_bbr_pace_per_sec); 14343 bbr->r_ctl.bbr_hptsi_per_second = optval; 14344 break; 14345 case TCP_BBR_PACE_DEL_TAR: 14346 BBR_OPTS_INC(tcp_bbr_pace_del_tar); 14347 bbr->r_ctl.bbr_hptsi_segments_delay_tar = optval; 14348 break; 14349 case TCP_BBR_PACE_SEG_MAX: 14350 BBR_OPTS_INC(tcp_bbr_pace_seg_max); 14351 bbr->r_ctl.bbr_hptsi_segments_max = optval; 14352 break; 14353 case TCP_BBR_PACE_SEG_MIN: 14354 BBR_OPTS_INC(tcp_bbr_pace_seg_min); 14355 bbr->r_ctl.bbr_hptsi_bytes_min = optval; 14356 break; 14357 case TCP_BBR_PACE_CROSS: 14358 BBR_OPTS_INC(tcp_bbr_pace_cross); 14359 bbr->r_ctl.bbr_cross_over = optval; 14360 break; 14361 case TCP_BBR_ALGORITHM: 14362 BBR_OPTS_INC(tcp_bbr_algorithm); 14363 if (optval && (bbr->rc_use_google == 0)) { 14364 /* Turn on the google mode */ 14365 bbr_google_mode_on(bbr); 14366 if ((optval > 3) && (optval < 500)) { 14367 /* 14368 * Must be at least greater than .3% 14369 * and must be less than 50.0%. 14370 */ 14371 bbr->r_ctl.bbr_google_discount = optval; 14372 } 14373 } else if ((optval == 0) && (bbr->rc_use_google == 1)) { 14374 /* Turn off the google mode */ 14375 bbr_google_mode_off(bbr); 14376 } 14377 break; 14378 case TCP_BBR_TSLIMITS: 14379 BBR_OPTS_INC(tcp_bbr_tslimits); 14380 if (optval == 1) 14381 bbr->rc_use_ts_limit = 1; 14382 else if (optval == 0) 14383 bbr->rc_use_ts_limit = 0; 14384 else 14385 error = EINVAL; 14386 break; 14387 14388 case TCP_BBR_IWINTSO: 14389 BBR_OPTS_INC(tcp_bbr_iwintso); 14390 if ((optval >= 0) && (optval < 128)) { 14391 uint32_t twin; 14392 14393 bbr->rc_init_win = optval; 14394 twin = bbr_initial_cwnd(bbr, tp); 14395 if ((bbr->rc_past_init_win == 0) && (twin > tp->snd_cwnd)) 14396 tp->snd_cwnd = twin; 14397 else 14398 error = EBUSY; 14399 } else 14400 error = EINVAL; 14401 break; 14402 case TCP_BBR_STARTUP_PG: 14403 BBR_OPTS_INC(tcp_bbr_startup_pg); 14404 if ((optval > 0) && (optval < BBR_MAX_GAIN_VALUE)) { 14405 bbr->r_ctl.rc_startup_pg = optval; 14406 if (bbr->rc_bbr_state == BBR_STATE_STARTUP) { 14407 bbr->r_ctl.rc_bbr_hptsi_gain = optval; 14408 } 14409 } else 14410 error = EINVAL; 14411 break; 14412 case TCP_BBR_DRAIN_PG: 14413 BBR_OPTS_INC(tcp_bbr_drain_pg); 14414 if ((optval > 0) && (optval < BBR_MAX_GAIN_VALUE)) 14415 bbr->r_ctl.rc_drain_pg = optval; 14416 else 14417 error = EINVAL; 14418 break; 14419 case TCP_BBR_PROBE_RTT_LEN: 14420 BBR_OPTS_INC(tcp_bbr_probertt_len); 14421 if (optval <= 1) 14422 reset_time_small(&bbr->r_ctl.rc_rttprop, (optval * USECS_IN_SECOND)); 14423 else 14424 error = EINVAL; 14425 break; 14426 case TCP_BBR_PROBE_RTT_GAIN: 14427 BBR_OPTS_INC(tcp_bbr_probertt_gain); 14428 if (optval <= BBR_UNIT) 14429 bbr->r_ctl.bbr_rttprobe_gain_val = optval; 14430 else 14431 error = EINVAL; 14432 break; 14433 case TCP_BBR_PROBE_RTT_INT: 14434 BBR_OPTS_INC(tcp_bbr_probe_rtt_int); 14435 if (optval > 1000) 14436 bbr->r_ctl.rc_probertt_int = optval; 14437 else 14438 error = EINVAL; 14439 break; 14440 case TCP_BBR_MIN_TOPACEOUT: 14441 BBR_OPTS_INC(tcp_bbr_topaceout); 14442 if (optval == 0) { 14443 bbr->no_pacing_until = 0; 14444 bbr->rc_no_pacing = 0; 14445 } else if (optval <= 0x00ff) { 14446 bbr->no_pacing_until = optval; 14447 if ((bbr->r_ctl.rc_pkt_epoch < bbr->no_pacing_until) && 14448 (bbr->rc_bbr_state == BBR_STATE_STARTUP)){ 14449 /* Turn on no pacing */ 14450 bbr->rc_no_pacing = 1; 14451 } 14452 } else 14453 error = EINVAL; 14454 break; 14455 case TCP_BBR_STARTUP_LOSS_EXIT: 14456 BBR_OPTS_INC(tcp_bbr_startup_loss_exit); 14457 bbr->rc_loss_exit = optval; 14458 break; 14459 case TCP_BBR_USEDEL_RATE: 14460 error = EINVAL; 14461 break; 14462 case TCP_BBR_MIN_RTO: 14463 BBR_OPTS_INC(tcp_bbr_min_rto); 14464 bbr->r_ctl.rc_min_rto_ms = optval; 14465 break; 14466 case TCP_BBR_MAX_RTO: 14467 BBR_OPTS_INC(tcp_bbr_max_rto); 14468 bbr->rc_max_rto_sec = optval; 14469 break; 14470 case TCP_RACK_MIN_TO: 14471 /* Minimum time between rack t-o's in ms */ 14472 BBR_OPTS_INC(tcp_rack_min_to); 14473 bbr->r_ctl.rc_min_to = optval; 14474 break; 14475 case TCP_RACK_REORD_THRESH: 14476 /* RACK reorder threshold (shift amount) */ 14477 BBR_OPTS_INC(tcp_rack_reord_thresh); 14478 if ((optval > 0) && (optval < 31)) 14479 bbr->r_ctl.rc_reorder_shift = optval; 14480 else 14481 error = EINVAL; 14482 break; 14483 case TCP_RACK_REORD_FADE: 14484 /* Does reordering fade after ms time */ 14485 BBR_OPTS_INC(tcp_rack_reord_fade); 14486 bbr->r_ctl.rc_reorder_fade = optval; 14487 break; 14488 case TCP_RACK_TLP_THRESH: 14489 /* RACK TLP theshold i.e. srtt+(srtt/N) */ 14490 BBR_OPTS_INC(tcp_rack_tlp_thresh); 14491 if (optval) 14492 bbr->rc_tlp_threshold = optval; 14493 else 14494 error = EINVAL; 14495 break; 14496 case TCP_BBR_USE_RACK_CHEAT: 14497 BBR_OPTS_INC(tcp_use_rackcheat); 14498 if (bbr->rc_use_google) { 14499 error = EINVAL; 14500 break; 14501 } 14502 BBR_OPTS_INC(tcp_rack_cheat); 14503 if (optval) 14504 bbr->bbr_use_rack_cheat = 1; 14505 else 14506 bbr->bbr_use_rack_cheat = 0; 14507 break; 14508 case TCP_BBR_FLOOR_MIN_TSO: 14509 BBR_OPTS_INC(tcp_utter_max_tso); 14510 if ((optval >= 0) && (optval < 40)) 14511 bbr->r_ctl.bbr_hptsi_segments_floor = optval; 14512 else 14513 error = EINVAL; 14514 break; 14515 case TCP_BBR_UTTER_MAX_TSO: 14516 BBR_OPTS_INC(tcp_utter_max_tso); 14517 if ((optval >= 0) && (optval < 0xffff)) 14518 bbr->r_ctl.bbr_utter_max = optval; 14519 else 14520 error = EINVAL; 14521 break; 14522 14523 case TCP_BBR_EXTRA_STATE: 14524 BBR_OPTS_INC(tcp_extra_state); 14525 if (optval) 14526 bbr->rc_use_idle_restart = 1; 14527 else 14528 bbr->rc_use_idle_restart = 0; 14529 break; 14530 case TCP_BBR_SEND_IWND_IN_TSO: 14531 BBR_OPTS_INC(tcp_iwnd_tso); 14532 if (optval) { 14533 bbr->bbr_init_win_cheat = 1; 14534 if (bbr->rc_past_init_win == 0) { 14535 uint32_t cts; 14536 cts = tcp_get_usecs(&bbr->rc_tv); 14537 tcp_bbr_tso_size_check(bbr, cts); 14538 } 14539 } else 14540 bbr->bbr_init_win_cheat = 0; 14541 break; 14542 case TCP_BBR_HDWR_PACE: 14543 BBR_OPTS_INC(tcp_hdwr_pacing); 14544 if (optval){ 14545 bbr->bbr_hdw_pace_ena = 1; 14546 bbr->bbr_attempt_hdwr_pace = 0; 14547 } else { 14548 bbr->bbr_hdw_pace_ena = 0; 14549 #ifdef RATELIMIT 14550 if (bbr->bbr_hdrw_pacing) { 14551 bbr->bbr_hdrw_pacing = 0; 14552 in_pcbdetach_txrtlmt(bbr->rc_inp); 14553 } 14554 #endif 14555 } 14556 break; 14557 14558 case TCP_DELACK: 14559 BBR_OPTS_INC(tcp_delack); 14560 if (optval < 100) { 14561 if (optval == 0) /* off */ 14562 tp->t_delayed_ack = 0; 14563 else if (optval == 1) /* on which is 2 */ 14564 tp->t_delayed_ack = 2; 14565 else /* higher than 2 and less than 100 */ 14566 tp->t_delayed_ack = optval; 14567 if (tp->t_flags & TF_DELACK) { 14568 tp->t_flags &= ~TF_DELACK; 14569 tp->t_flags |= TF_ACKNOW; 14570 NET_EPOCH_ENTER(et); 14571 bbr_output(tp); 14572 NET_EPOCH_EXIT(et); 14573 } 14574 } else 14575 error = EINVAL; 14576 break; 14577 case TCP_RACK_PKT_DELAY: 14578 /* RACK added ms i.e. rack-rtt + reord + N */ 14579 BBR_OPTS_INC(tcp_rack_pkt_delay); 14580 bbr->r_ctl.rc_pkt_delay = optval; 14581 break; 14582 #ifdef NETFLIX_PEAKRATE 14583 case TCP_MAXPEAKRATE: 14584 BBR_OPTS_INC(tcp_maxpeak); 14585 error = tcp_set_maxpeakrate(tp, optval); 14586 if (!error) 14587 tp->t_peakrate_thr = tp->t_maxpeakrate; 14588 break; 14589 #endif 14590 case TCP_BBR_RETRAN_WTSO: 14591 BBR_OPTS_INC(tcp_retran_wtso); 14592 if (optval) 14593 bbr->rc_resends_use_tso = 1; 14594 else 14595 bbr->rc_resends_use_tso = 0; 14596 break; 14597 case TCP_DATA_AFTER_CLOSE: 14598 BBR_OPTS_INC(tcp_data_ac); 14599 if (optval) 14600 bbr->rc_allow_data_af_clo = 1; 14601 else 14602 bbr->rc_allow_data_af_clo = 0; 14603 break; 14604 case TCP_BBR_POLICER_DETECT: 14605 BBR_OPTS_INC(tcp_policer_det); 14606 if (bbr->rc_use_google == 0) 14607 error = EINVAL; 14608 else if (optval) 14609 bbr->r_use_policer = 1; 14610 else 14611 bbr->r_use_policer = 0; 14612 break; 14613 14614 case TCP_BBR_TSTMP_RAISES: 14615 BBR_OPTS_INC(tcp_ts_raises); 14616 if (optval) 14617 bbr->ts_can_raise = 1; 14618 else 14619 bbr->ts_can_raise = 0; 14620 break; 14621 case TCP_BBR_TMR_PACE_OH: 14622 BBR_OPTS_INC(tcp_pacing_oh_tmr); 14623 if (bbr->rc_use_google) { 14624 error = EINVAL; 14625 } else { 14626 if (optval) 14627 bbr->r_ctl.rc_incr_tmrs = 1; 14628 else 14629 bbr->r_ctl.rc_incr_tmrs = 0; 14630 } 14631 break; 14632 case TCP_BBR_PACE_OH: 14633 BBR_OPTS_INC(tcp_pacing_oh); 14634 if (bbr->rc_use_google) { 14635 error = EINVAL; 14636 } else { 14637 if (optval > (BBR_INCL_TCP_OH| 14638 BBR_INCL_IP_OH| 14639 BBR_INCL_ENET_OH)) { 14640 error = EINVAL; 14641 break; 14642 } 14643 if (optval & BBR_INCL_TCP_OH) 14644 bbr->r_ctl.rc_inc_tcp_oh = 1; 14645 else 14646 bbr->r_ctl.rc_inc_tcp_oh = 0; 14647 if (optval & BBR_INCL_IP_OH) 14648 bbr->r_ctl.rc_inc_ip_oh = 1; 14649 else 14650 bbr->r_ctl.rc_inc_ip_oh = 0; 14651 if (optval & BBR_INCL_ENET_OH) 14652 bbr->r_ctl.rc_inc_enet_oh = 1; 14653 else 14654 bbr->r_ctl.rc_inc_enet_oh = 0; 14655 } 14656 break; 14657 default: 14658 return (tcp_default_ctloutput(so, sopt, inp, tp)); 14659 break; 14660 } 14661 #ifdef NETFLIX_STATS 14662 tcp_log_socket_option(tp, sopt->sopt_name, optval, error); 14663 #endif 14664 INP_WUNLOCK(inp); 14665 return (error); 14666 } 14667 14668 /* 14669 * return 0 on success, error-num on failure 14670 */ 14671 static int 14672 bbr_get_sockopt(struct socket *so, struct sockopt *sopt, 14673 struct inpcb *inp, struct tcpcb *tp, struct tcp_bbr *bbr) 14674 { 14675 int32_t error, optval; 14676 14677 /* 14678 * Because all our options are either boolean or an int, we can just 14679 * pull everything into optval and then unlock and copy. If we ever 14680 * add a option that is not a int, then this will have quite an 14681 * impact to this routine. 14682 */ 14683 switch (sopt->sopt_name) { 14684 case TCP_BBR_PACE_PER_SEC: 14685 optval = bbr->r_ctl.bbr_hptsi_per_second; 14686 break; 14687 case TCP_BBR_PACE_DEL_TAR: 14688 optval = bbr->r_ctl.bbr_hptsi_segments_delay_tar; 14689 break; 14690 case TCP_BBR_PACE_SEG_MAX: 14691 optval = bbr->r_ctl.bbr_hptsi_segments_max; 14692 break; 14693 case TCP_BBR_MIN_TOPACEOUT: 14694 optval = bbr->no_pacing_until; 14695 break; 14696 case TCP_BBR_PACE_SEG_MIN: 14697 optval = bbr->r_ctl.bbr_hptsi_bytes_min; 14698 break; 14699 case TCP_BBR_PACE_CROSS: 14700 optval = bbr->r_ctl.bbr_cross_over; 14701 break; 14702 case TCP_BBR_ALGORITHM: 14703 optval = bbr->rc_use_google; 14704 break; 14705 case TCP_BBR_TSLIMITS: 14706 optval = bbr->rc_use_ts_limit; 14707 break; 14708 case TCP_BBR_IWINTSO: 14709 optval = bbr->rc_init_win; 14710 break; 14711 case TCP_BBR_STARTUP_PG: 14712 optval = bbr->r_ctl.rc_startup_pg; 14713 break; 14714 case TCP_BBR_DRAIN_PG: 14715 optval = bbr->r_ctl.rc_drain_pg; 14716 break; 14717 case TCP_BBR_PROBE_RTT_INT: 14718 optval = bbr->r_ctl.rc_probertt_int; 14719 break; 14720 case TCP_BBR_PROBE_RTT_LEN: 14721 optval = (bbr->r_ctl.rc_rttprop.cur_time_limit / USECS_IN_SECOND); 14722 break; 14723 case TCP_BBR_PROBE_RTT_GAIN: 14724 optval = bbr->r_ctl.bbr_rttprobe_gain_val; 14725 break; 14726 case TCP_BBR_STARTUP_LOSS_EXIT: 14727 optval = bbr->rc_loss_exit; 14728 break; 14729 case TCP_BBR_USEDEL_RATE: 14730 error = EINVAL; 14731 break; 14732 case TCP_BBR_MIN_RTO: 14733 optval = bbr->r_ctl.rc_min_rto_ms; 14734 break; 14735 case TCP_BBR_MAX_RTO: 14736 optval = bbr->rc_max_rto_sec; 14737 break; 14738 case TCP_RACK_PACE_MAX_SEG: 14739 /* Max segments in a pace */ 14740 optval = bbr->r_ctl.rc_pace_max_segs; 14741 break; 14742 case TCP_RACK_MIN_TO: 14743 /* Minimum time between rack t-o's in ms */ 14744 optval = bbr->r_ctl.rc_min_to; 14745 break; 14746 case TCP_RACK_REORD_THRESH: 14747 /* RACK reorder threshold (shift amount) */ 14748 optval = bbr->r_ctl.rc_reorder_shift; 14749 break; 14750 case TCP_RACK_REORD_FADE: 14751 /* Does reordering fade after ms time */ 14752 optval = bbr->r_ctl.rc_reorder_fade; 14753 break; 14754 case TCP_BBR_USE_RACK_CHEAT: 14755 /* Do we use the rack cheat for rxt */ 14756 optval = bbr->bbr_use_rack_cheat; 14757 break; 14758 case TCP_BBR_FLOOR_MIN_TSO: 14759 optval = bbr->r_ctl.bbr_hptsi_segments_floor; 14760 break; 14761 case TCP_BBR_UTTER_MAX_TSO: 14762 optval = bbr->r_ctl.bbr_utter_max; 14763 break; 14764 case TCP_BBR_SEND_IWND_IN_TSO: 14765 /* Do we send TSO size segments initially */ 14766 optval = bbr->bbr_init_win_cheat; 14767 break; 14768 case TCP_BBR_EXTRA_STATE: 14769 optval = bbr->rc_use_idle_restart; 14770 break; 14771 case TCP_RACK_TLP_THRESH: 14772 /* RACK TLP theshold i.e. srtt+(srtt/N) */ 14773 optval = bbr->rc_tlp_threshold; 14774 break; 14775 case TCP_RACK_PKT_DELAY: 14776 /* RACK added ms i.e. rack-rtt + reord + N */ 14777 optval = bbr->r_ctl.rc_pkt_delay; 14778 break; 14779 case TCP_BBR_RETRAN_WTSO: 14780 optval = bbr->rc_resends_use_tso; 14781 break; 14782 case TCP_DATA_AFTER_CLOSE: 14783 optval = bbr->rc_allow_data_af_clo; 14784 break; 14785 case TCP_DELACK: 14786 optval = tp->t_delayed_ack; 14787 break; 14788 case TCP_BBR_HDWR_PACE: 14789 optval = bbr->bbr_hdw_pace_ena; 14790 break; 14791 case TCP_BBR_POLICER_DETECT: 14792 optval = bbr->r_use_policer; 14793 break; 14794 case TCP_BBR_TSTMP_RAISES: 14795 optval = bbr->ts_can_raise; 14796 break; 14797 case TCP_BBR_TMR_PACE_OH: 14798 optval = bbr->r_ctl.rc_incr_tmrs; 14799 break; 14800 case TCP_BBR_PACE_OH: 14801 optval = 0; 14802 if (bbr->r_ctl.rc_inc_tcp_oh) 14803 optval |= BBR_INCL_TCP_OH; 14804 if (bbr->r_ctl.rc_inc_ip_oh) 14805 optval |= BBR_INCL_IP_OH; 14806 if (bbr->r_ctl.rc_inc_enet_oh) 14807 optval |= BBR_INCL_ENET_OH; 14808 break; 14809 default: 14810 return (tcp_default_ctloutput(so, sopt, inp, tp)); 14811 break; 14812 } 14813 INP_WUNLOCK(inp); 14814 error = sooptcopyout(sopt, &optval, sizeof optval); 14815 return (error); 14816 } 14817 14818 /* 14819 * return 0 on success, error-num on failure 14820 */ 14821 static int 14822 bbr_ctloutput(struct socket *so, struct sockopt *sopt, struct inpcb *inp, struct tcpcb *tp) 14823 { 14824 int32_t error = EINVAL; 14825 struct tcp_bbr *bbr; 14826 14827 bbr = (struct tcp_bbr *)tp->t_fb_ptr; 14828 if (bbr == NULL) { 14829 /* Huh? */ 14830 goto out; 14831 } 14832 if (sopt->sopt_dir == SOPT_SET) { 14833 return (bbr_set_sockopt(so, sopt, inp, tp, bbr)); 14834 } else if (sopt->sopt_dir == SOPT_GET) { 14835 return (bbr_get_sockopt(so, sopt, inp, tp, bbr)); 14836 } 14837 out: 14838 INP_WUNLOCK(inp); 14839 return (error); 14840 } 14841 14842 static int 14843 bbr_pru_options(struct tcpcb *tp, int flags) 14844 { 14845 if (flags & PRUS_OOB) 14846 return (EOPNOTSUPP); 14847 return (0); 14848 } 14849 14850 struct tcp_function_block __tcp_bbr = { 14851 .tfb_tcp_block_name = __XSTRING(STACKNAME), 14852 .tfb_tcp_output = bbr_output, 14853 .tfb_do_queued_segments = ctf_do_queued_segments, 14854 .tfb_do_segment_nounlock = bbr_do_segment_nounlock, 14855 .tfb_tcp_do_segment = bbr_do_segment, 14856 .tfb_tcp_ctloutput = bbr_ctloutput, 14857 .tfb_tcp_fb_init = bbr_init, 14858 .tfb_tcp_fb_fini = bbr_fini, 14859 .tfb_tcp_timer_stop_all = bbr_stopall, 14860 .tfb_tcp_timer_activate = bbr_timer_activate, 14861 .tfb_tcp_timer_active = bbr_timer_active, 14862 .tfb_tcp_timer_stop = bbr_timer_stop, 14863 .tfb_tcp_rexmit_tmr = bbr_remxt_tmr, 14864 .tfb_tcp_handoff_ok = bbr_handoff_ok, 14865 .tfb_tcp_mtu_chg = bbr_mtu_chg, 14866 .tfb_pru_options = bbr_pru_options, 14867 }; 14868 14869 static const char *bbr_stack_names[] = { 14870 __XSTRING(STACKNAME), 14871 #ifdef STACKALIAS 14872 __XSTRING(STACKALIAS), 14873 #endif 14874 }; 14875 14876 static bool bbr_mod_inited = false; 14877 14878 static int 14879 tcp_addbbr(module_t mod, int32_t type, void *data) 14880 { 14881 int32_t err = 0; 14882 int num_stacks; 14883 14884 switch (type) { 14885 case MOD_LOAD: 14886 printf("Attempting to load " __XSTRING(MODNAME) "\n"); 14887 bbr_zone = uma_zcreate(__XSTRING(MODNAME) "_map", 14888 sizeof(struct bbr_sendmap), 14889 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 14890 bbr_pcb_zone = uma_zcreate(__XSTRING(MODNAME) "_pcb", 14891 sizeof(struct tcp_bbr), 14892 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0); 14893 sysctl_ctx_init(&bbr_sysctl_ctx); 14894 bbr_sysctl_root = SYSCTL_ADD_NODE(&bbr_sysctl_ctx, 14895 SYSCTL_STATIC_CHILDREN(_net_inet_tcp), 14896 OID_AUTO, 14897 #ifdef STACKALIAS 14898 __XSTRING(STACKALIAS), 14899 #else 14900 __XSTRING(STACKNAME), 14901 #endif 14902 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 14903 ""); 14904 if (bbr_sysctl_root == NULL) { 14905 printf("Failed to add sysctl node\n"); 14906 err = EFAULT; 14907 goto free_uma; 14908 } 14909 bbr_init_sysctls(); 14910 num_stacks = nitems(bbr_stack_names); 14911 err = register_tcp_functions_as_names(&__tcp_bbr, M_WAITOK, 14912 bbr_stack_names, &num_stacks); 14913 if (err) { 14914 printf("Failed to register %s stack name for " 14915 "%s module\n", bbr_stack_names[num_stacks], 14916 __XSTRING(MODNAME)); 14917 sysctl_ctx_free(&bbr_sysctl_ctx); 14918 free_uma: 14919 uma_zdestroy(bbr_zone); 14920 uma_zdestroy(bbr_pcb_zone); 14921 bbr_counter_destroy(); 14922 printf("Failed to register " __XSTRING(MODNAME) 14923 " module err:%d\n", err); 14924 return (err); 14925 } 14926 tcp_lro_reg_mbufq(); 14927 bbr_mod_inited = true; 14928 printf(__XSTRING(MODNAME) " is now available\n"); 14929 break; 14930 case MOD_QUIESCE: 14931 err = deregister_tcp_functions(&__tcp_bbr, true, false); 14932 break; 14933 case MOD_UNLOAD: 14934 err = deregister_tcp_functions(&__tcp_bbr, false, true); 14935 if (err == EBUSY) 14936 break; 14937 if (bbr_mod_inited) { 14938 uma_zdestroy(bbr_zone); 14939 uma_zdestroy(bbr_pcb_zone); 14940 sysctl_ctx_free(&bbr_sysctl_ctx); 14941 bbr_counter_destroy(); 14942 printf(__XSTRING(MODNAME) 14943 " is now no longer available\n"); 14944 bbr_mod_inited = false; 14945 } 14946 tcp_lro_dereg_mbufq(); 14947 err = 0; 14948 break; 14949 default: 14950 return (EOPNOTSUPP); 14951 } 14952 return (err); 14953 } 14954 14955 static moduledata_t tcp_bbr = { 14956 .name = __XSTRING(MODNAME), 14957 .evhand = tcp_addbbr, 14958 .priv = 0 14959 }; 14960 14961 MODULE_VERSION(MODNAME, 1); 14962 DECLARE_MODULE(MODNAME, tcp_bbr, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY); 14963 MODULE_DEPEND(MODNAME, tcphpts, 1, 1, 1); 14964