1/*- 2 * Copyright (c) 2001-2007, by Cisco Systems, Inc. All rights reserved. 3 * Copyright (c) 2008-2012, by Randall Stewart. All rights reserved. 4 * Copyright (c) 2008-2012, by Michael Tuexen. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions are met: 8 * 9 * a) Redistributions of source code must retain the above copyright notice, 10 * this list of conditions and the following disclaimer. 11 * 12 * b) Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in 14 * the documentation and/or other materials provided with the distribution. 15 * 16 * c) Neither the name of Cisco Systems, Inc. nor the names of its 17 * contributors may be used to endorse or promote products derived 18 * from this software without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 21 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 22 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 24 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 30 * THE POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33#include <sys/cdefs.h> 34__FBSDID("$FreeBSD$"); 35 36#include <netinet/sctp_os.h> 37#include <netinet/sctp_var.h> 38#include <netinet/sctp_sysctl.h> 39#include <netinet/sctp_pcb.h> 40#include <netinet/sctp_header.h> 41#include <netinet/sctputil.h> 42#include <netinet/sctp_output.h> 43#include <netinet/sctp_input.h> 44#include <netinet/sctp_indata.h> 45#include <netinet/sctp_uio.h> 46#include <netinet/sctp_timer.h> 47#include <netinet/sctp_auth.h> 48#include <netinet/sctp_asconf.h> 49#include <netinet/sctp_dtrace_declare.h> 50 51#define SHIFT_MPTCP_MULTI_N 40 52#define SHIFT_MPTCP_MULTI_Z 16 53#define SHIFT_MPTCP_MULTI 8 54 55static void 56sctp_set_initial_cc_param(struct sctp_tcb *stcb, struct sctp_nets *net) 57{ 58 struct sctp_association *assoc; 59 uint32_t cwnd_in_mtu; 60 61 assoc = &stcb->asoc; 62 cwnd_in_mtu = SCTP_BASE_SYSCTL(sctp_initial_cwnd); 63 if (cwnd_in_mtu == 0) { 64 /* Using 0 means that the value of RFC 4960 is used. */ 65 net->cwnd = min((net->mtu * 4), max((2 * net->mtu), SCTP_INITIAL_CWND)); 66 } else { 67 /* 68 * We take the minimum of the burst limit and the initial 69 * congestion window. 70 */ 71 if ((assoc->max_burst > 0) && (cwnd_in_mtu > assoc->max_burst)) 72 cwnd_in_mtu = assoc->max_burst; 73 net->cwnd = (net->mtu - sizeof(struct sctphdr)) * cwnd_in_mtu; 74 } 75 if ((stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV1) || 76 (stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV2)) { 77 /* In case of resource pooling initialize appropriately */ 78 net->cwnd /= assoc->numnets; 79 if (net->cwnd < (net->mtu - sizeof(struct sctphdr))) { 80 net->cwnd = net->mtu - sizeof(struct sctphdr); 81 } 82 } 83 net->ssthresh = assoc->peers_rwnd; 84 SDT_PROBE(sctp, cwnd, net, init, 85 stcb->asoc.my_vtag, ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)), net, 86 0, net->cwnd); 87 if (SCTP_BASE_SYSCTL(sctp_logging_level) & 88 (SCTP_CWND_MONITOR_ENABLE | SCTP_CWND_LOGGING_ENABLE)) { 89 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_INITIALIZATION); 90 } 91} 92 93static void 94sctp_cwnd_update_after_fr(struct sctp_tcb *stcb, 95 struct sctp_association *asoc) 96{ 97 struct sctp_nets *net; 98 uint32_t t_ssthresh, t_cwnd; 99 uint64_t t_ucwnd_sbw; 100 101 /* MT FIXME: Don't compute this over and over again */ 102 t_ssthresh = 0; 103 t_cwnd = 0; 104 t_ucwnd_sbw = 0; 105 if ((asoc->sctp_cmt_on_off == SCTP_CMT_RPV1) || 106 (asoc->sctp_cmt_on_off == SCTP_CMT_RPV2)) { 107 TAILQ_FOREACH(net, &asoc->nets, sctp_next) { 108 t_ssthresh += net->ssthresh; 109 t_cwnd += net->cwnd; 110 if (net->lastsa > 0) { 111 t_ucwnd_sbw += (uint64_t) net->cwnd / (uint64_t) net->lastsa; 112 } 113 } 114 if (t_ucwnd_sbw == 0) { 115 t_ucwnd_sbw = 1; 116 } 117 } 118 /*- 119 * CMT fast recovery code. Need to debug. ((sctp_cmt_on_off > 0) && 120 * (net->fast_retran_loss_recovery == 0))) 121 */ 122 TAILQ_FOREACH(net, &asoc->nets, sctp_next) { 123 if ((asoc->fast_retran_loss_recovery == 0) || 124 (asoc->sctp_cmt_on_off > 0)) { 125 /* out of a RFC2582 Fast recovery window? */ 126 if (net->net_ack > 0) { 127 /* 128 * per section 7.2.3, are there any 129 * destinations that had a fast retransmit 130 * to them. If so what we need to do is 131 * adjust ssthresh and cwnd. 132 */ 133 struct sctp_tmit_chunk *lchk; 134 int old_cwnd = net->cwnd; 135 136 if ((asoc->sctp_cmt_on_off == SCTP_CMT_RPV1) || 137 (asoc->sctp_cmt_on_off == SCTP_CMT_RPV2)) { 138 if (asoc->sctp_cmt_on_off == SCTP_CMT_RPV1) { 139 net->ssthresh = (uint32_t) (((uint64_t) 4 * 140 (uint64_t) net->mtu * 141 (uint64_t) net->ssthresh) / 142 (uint64_t) t_ssthresh); 143 144 } 145 if (asoc->sctp_cmt_on_off == SCTP_CMT_RPV2) { 146 uint32_t srtt; 147 148 srtt = net->lastsa; 149 /* 150 * lastsa>>3; we don't need 151 * to devide ... 152 */ 153 if (srtt == 0) { 154 srtt = 1; 155 } 156 /* 157 * Short Version => Equal to 158 * Contel Version MBe 159 */ 160 net->ssthresh = (uint32_t) (((uint64_t) 4 * 161 (uint64_t) net->mtu * 162 (uint64_t) net->cwnd) / 163 ((uint64_t) srtt * 164 t_ucwnd_sbw)); 165 /* INCREASE FACTOR */ ; 166 } 167 if ((net->cwnd > t_cwnd / 2) && 168 (net->ssthresh < net->cwnd - t_cwnd / 2)) { 169 net->ssthresh = net->cwnd - t_cwnd / 2; 170 } 171 if (net->ssthresh < net->mtu) { 172 net->ssthresh = net->mtu; 173 } 174 } else { 175 net->ssthresh = net->cwnd / 2; 176 if (net->ssthresh < (net->mtu * 2)) { 177 net->ssthresh = 2 * net->mtu; 178 } 179 } 180 net->cwnd = net->ssthresh; 181 SDT_PROBE(sctp, cwnd, net, fr, 182 stcb->asoc.my_vtag, ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)), net, 183 old_cwnd, net->cwnd); 184 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 185 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), 186 SCTP_CWND_LOG_FROM_FR); 187 } 188 lchk = TAILQ_FIRST(&asoc->send_queue); 189 190 net->partial_bytes_acked = 0; 191 /* Turn on fast recovery window */ 192 asoc->fast_retran_loss_recovery = 1; 193 if (lchk == NULL) { 194 /* Mark end of the window */ 195 asoc->fast_recovery_tsn = asoc->sending_seq - 1; 196 } else { 197 asoc->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1; 198 } 199 200 /* 201 * CMT fast recovery -- per destination 202 * recovery variable. 203 */ 204 net->fast_retran_loss_recovery = 1; 205 206 if (lchk == NULL) { 207 /* Mark end of the window */ 208 net->fast_recovery_tsn = asoc->sending_seq - 1; 209 } else { 210 net->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1; 211 } 212 213 sctp_timer_stop(SCTP_TIMER_TYPE_SEND, 214 stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_32); 215 sctp_timer_start(SCTP_TIMER_TYPE_SEND, 216 stcb->sctp_ep, stcb, net); 217 } 218 } else if (net->net_ack > 0) { 219 /* 220 * Mark a peg that we WOULD have done a cwnd 221 * reduction but RFC2582 prevented this action. 222 */ 223 SCTP_STAT_INCR(sctps_fastretransinrtt); 224 } 225 } 226} 227 228/* Defines for instantaneous bw decisions */ 229#define SCTP_INST_LOOSING 1 /* Loosing to other flows */ 230#define SCTP_INST_NEUTRAL 2 /* Neutral, no indication */ 231#define SCTP_INST_GAINING 3 /* Gaining, step down possible */ 232 233 234static int 235cc_bw_same(struct sctp_tcb *stcb, struct sctp_nets *net, uint64_t nbw, 236 uint64_t rtt_offset, uint64_t vtag, uint8_t inst_ind) 237{ 238 uint64_t oth, probepoint; 239 240 probepoint = (((uint64_t) net->cwnd) << 32); 241 if (net->rtt > net->cc_mod.rtcc.lbw_rtt + rtt_offset) { 242 /* 243 * rtt increased we don't update bw.. so we don't update the 244 * rtt either. 245 */ 246 /* Probe point 5 */ 247 probepoint |= ((5 << 16) | 1); 248 SDT_PROBE(sctp, cwnd, net, rttvar, 249 vtag, 250 ((net->cc_mod.rtcc.lbw << 32) | nbw), 251 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 252 net->flight_size, 253 probepoint); 254 if ((net->cc_mod.rtcc.steady_step) && (inst_ind != SCTP_INST_LOOSING)) { 255 if (net->cc_mod.rtcc.last_step_state == 5) 256 net->cc_mod.rtcc.step_cnt++; 257 else 258 net->cc_mod.rtcc.step_cnt = 1; 259 net->cc_mod.rtcc.last_step_state = 5; 260 if ((net->cc_mod.rtcc.step_cnt == net->cc_mod.rtcc.steady_step) || 261 ((net->cc_mod.rtcc.step_cnt > net->cc_mod.rtcc.steady_step) && 262 ((net->cc_mod.rtcc.step_cnt % net->cc_mod.rtcc.steady_step) == 0))) { 263 /* Try a step down */ 264 oth = net->cc_mod.rtcc.vol_reduce; 265 oth <<= 16; 266 oth |= net->cc_mod.rtcc.step_cnt; 267 oth <<= 16; 268 oth |= net->cc_mod.rtcc.last_step_state; 269 SDT_PROBE(sctp, cwnd, net, rttstep, 270 vtag, 271 ((net->cc_mod.rtcc.lbw << 32) | nbw), 272 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 273 oth, 274 probepoint); 275 if (net->cwnd > (4 * net->mtu)) { 276 net->cwnd -= net->mtu; 277 net->cc_mod.rtcc.vol_reduce++; 278 } else { 279 net->cc_mod.rtcc.step_cnt = 0; 280 } 281 } 282 } 283 return (1); 284 } 285 if (net->rtt < net->cc_mod.rtcc.lbw_rtt - rtt_offset) { 286 /* 287 * rtt decreased, there could be more room. we update both 288 * the bw and the rtt here to lock this in as a good step 289 * down. 290 */ 291 /* Probe point 6 */ 292 probepoint |= ((6 << 16) | 0); 293 SDT_PROBE(sctp, cwnd, net, rttvar, 294 vtag, 295 ((net->cc_mod.rtcc.lbw << 32) | nbw), 296 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 297 net->flight_size, 298 probepoint); 299 if (net->cc_mod.rtcc.steady_step) { 300 oth = net->cc_mod.rtcc.vol_reduce; 301 oth <<= 16; 302 oth |= net->cc_mod.rtcc.step_cnt; 303 oth <<= 16; 304 oth |= net->cc_mod.rtcc.last_step_state; 305 SDT_PROBE(sctp, cwnd, net, rttstep, 306 vtag, 307 ((net->cc_mod.rtcc.lbw << 32) | nbw), 308 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 309 oth, 310 probepoint); 311 if ((net->cc_mod.rtcc.last_step_state == 5) && 312 (net->cc_mod.rtcc.step_cnt > net->cc_mod.rtcc.steady_step)) { 313 /* Step down worked */ 314 net->cc_mod.rtcc.step_cnt = 0; 315 return (1); 316 } else { 317 net->cc_mod.rtcc.last_step_state = 6; 318 net->cc_mod.rtcc.step_cnt = 0; 319 } 320 } 321 net->cc_mod.rtcc.lbw = nbw; 322 net->cc_mod.rtcc.lbw_rtt = net->rtt; 323 net->cc_mod.rtcc.cwnd_at_bw_set = net->cwnd; 324 if (inst_ind == SCTP_INST_GAINING) 325 return (1); 326 else if (inst_ind == SCTP_INST_NEUTRAL) 327 return (1); 328 else 329 return (0); 330 } 331 /* 332 * Ok bw and rtt remained the same .. no update to any 333 */ 334 /* Probe point 7 */ 335 probepoint |= ((7 << 16) | net->cc_mod.rtcc.ret_from_eq); 336 SDT_PROBE(sctp, cwnd, net, rttvar, 337 vtag, 338 ((net->cc_mod.rtcc.lbw << 32) | nbw), 339 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 340 net->flight_size, 341 probepoint); 342 if ((net->cc_mod.rtcc.steady_step) && (inst_ind != SCTP_INST_LOOSING)) { 343 if (net->cc_mod.rtcc.last_step_state == 5) 344 net->cc_mod.rtcc.step_cnt++; 345 else 346 net->cc_mod.rtcc.step_cnt = 1; 347 net->cc_mod.rtcc.last_step_state = 5; 348 if ((net->cc_mod.rtcc.step_cnt == net->cc_mod.rtcc.steady_step) || 349 ((net->cc_mod.rtcc.step_cnt > net->cc_mod.rtcc.steady_step) && 350 ((net->cc_mod.rtcc.step_cnt % net->cc_mod.rtcc.steady_step) == 0))) { 351 /* Try a step down */ 352 if (net->cwnd > (4 * net->mtu)) { 353 net->cwnd -= net->mtu; 354 net->cc_mod.rtcc.vol_reduce++; 355 return (1); 356 } else { 357 net->cc_mod.rtcc.step_cnt = 0; 358 } 359 } 360 } 361 if (inst_ind == SCTP_INST_GAINING) 362 return (1); 363 else if (inst_ind == SCTP_INST_NEUTRAL) 364 return (1); 365 else 366 return ((int)net->cc_mod.rtcc.ret_from_eq); 367} 368 369static int 370cc_bw_decrease(struct sctp_tcb *stcb, struct sctp_nets *net, uint64_t nbw, uint64_t rtt_offset, 371 uint64_t vtag, uint8_t inst_ind) 372{ 373 uint64_t oth, probepoint; 374 375 /* Bandwidth decreased. */ 376 probepoint = (((uint64_t) net->cwnd) << 32); 377 if (net->rtt > net->cc_mod.rtcc.lbw_rtt + rtt_offset) { 378 /* rtt increased */ 379 /* Did we add more */ 380 if ((net->cwnd > net->cc_mod.rtcc.cwnd_at_bw_set) && 381 (inst_ind != SCTP_INST_LOOSING)) { 382 /* We caused it maybe.. back off? */ 383 /* PROBE POINT 1 */ 384 probepoint |= ((1 << 16) | 1); 385 SDT_PROBE(sctp, cwnd, net, rttvar, 386 vtag, 387 ((net->cc_mod.rtcc.lbw << 32) | nbw), 388 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 389 net->flight_size, 390 probepoint); 391 if (net->cc_mod.rtcc.ret_from_eq) { 392 /* 393 * Switch over to CA if we are less 394 * aggressive 395 */ 396 net->ssthresh = net->cwnd - 1; 397 net->partial_bytes_acked = 0; 398 } 399 return (1); 400 } 401 /* Probe point 2 */ 402 probepoint |= ((2 << 16) | 0); 403 SDT_PROBE(sctp, cwnd, net, rttvar, 404 vtag, 405 ((net->cc_mod.rtcc.lbw << 32) | nbw), 406 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 407 net->flight_size, 408 probepoint); 409 /* Someone else - fight for more? */ 410 if (net->cc_mod.rtcc.steady_step) { 411 oth = net->cc_mod.rtcc.vol_reduce; 412 oth <<= 16; 413 oth |= net->cc_mod.rtcc.step_cnt; 414 oth <<= 16; 415 oth |= net->cc_mod.rtcc.last_step_state; 416 SDT_PROBE(sctp, cwnd, net, rttstep, 417 vtag, 418 ((net->cc_mod.rtcc.lbw << 32) | nbw), 419 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 420 oth, 421 probepoint); 422 /* 423 * Did we voluntarily give up some? if so take one 424 * back please 425 */ 426 if ((net->cc_mod.rtcc.vol_reduce) && 427 (inst_ind != SCTP_INST_GAINING)) { 428 net->cwnd += net->mtu; 429 net->cc_mod.rtcc.vol_reduce--; 430 } 431 net->cc_mod.rtcc.last_step_state = 2; 432 net->cc_mod.rtcc.step_cnt = 0; 433 } 434 goto out_decision; 435 } else if (net->rtt < net->cc_mod.rtcc.lbw_rtt - rtt_offset) { 436 /* bw & rtt decreased */ 437 /* Probe point 3 */ 438 probepoint |= ((3 << 16) | 0); 439 SDT_PROBE(sctp, cwnd, net, rttvar, 440 vtag, 441 ((net->cc_mod.rtcc.lbw << 32) | nbw), 442 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 443 net->flight_size, 444 probepoint); 445 if (net->cc_mod.rtcc.steady_step) { 446 oth = net->cc_mod.rtcc.vol_reduce; 447 oth <<= 16; 448 oth |= net->cc_mod.rtcc.step_cnt; 449 oth <<= 16; 450 oth |= net->cc_mod.rtcc.last_step_state; 451 SDT_PROBE(sctp, cwnd, net, rttstep, 452 vtag, 453 ((net->cc_mod.rtcc.lbw << 32) | nbw), 454 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 455 oth, 456 probepoint); 457 if ((net->cc_mod.rtcc.vol_reduce) && 458 (inst_ind != SCTP_INST_GAINING)) { 459 net->cwnd += net->mtu; 460 net->cc_mod.rtcc.vol_reduce--; 461 } 462 net->cc_mod.rtcc.last_step_state = 3; 463 net->cc_mod.rtcc.step_cnt = 0; 464 } 465 goto out_decision; 466 } 467 /* The bw decreased but rtt stayed the same */ 468 /* Probe point 4 */ 469 probepoint |= ((4 << 16) | 0); 470 SDT_PROBE(sctp, cwnd, net, rttvar, 471 vtag, 472 ((net->cc_mod.rtcc.lbw << 32) | nbw), 473 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 474 net->flight_size, 475 probepoint); 476 if (net->cc_mod.rtcc.steady_step) { 477 oth = net->cc_mod.rtcc.vol_reduce; 478 oth <<= 16; 479 oth |= net->cc_mod.rtcc.step_cnt; 480 oth <<= 16; 481 oth |= net->cc_mod.rtcc.last_step_state; 482 SDT_PROBE(sctp, cwnd, net, rttstep, 483 vtag, 484 ((net->cc_mod.rtcc.lbw << 32) | nbw), 485 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 486 oth, 487 probepoint); 488 if ((net->cc_mod.rtcc.vol_reduce) && 489 (inst_ind != SCTP_INST_GAINING)) { 490 net->cwnd += net->mtu; 491 net->cc_mod.rtcc.vol_reduce--; 492 } 493 net->cc_mod.rtcc.last_step_state = 4; 494 net->cc_mod.rtcc.step_cnt = 0; 495 } 496out_decision: 497 net->cc_mod.rtcc.lbw = nbw; 498 net->cc_mod.rtcc.lbw_rtt = net->rtt; 499 net->cc_mod.rtcc.cwnd_at_bw_set = net->cwnd; 500 if (inst_ind == SCTP_INST_GAINING) { 501 return (1); 502 } else { 503 return (0); 504 } 505} 506 507static int 508cc_bw_increase(struct sctp_tcb *stcb, struct sctp_nets *net, uint64_t nbw, uint64_t vtag) 509{ 510 uint64_t oth, probepoint; 511 512 /* 513 * BW increased, so update and return 0, since all actions in our 514 * table say to do the normal CC update. Note that we pay no 515 * attention to the inst_ind since our overall sum is increasing. 516 */ 517 /* PROBE POINT 0 */ 518 probepoint = (((uint64_t) net->cwnd) << 32); 519 SDT_PROBE(sctp, cwnd, net, rttvar, 520 vtag, 521 ((net->cc_mod.rtcc.lbw << 32) | nbw), 522 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 523 net->flight_size, 524 probepoint); 525 if (net->cc_mod.rtcc.steady_step) { 526 oth = net->cc_mod.rtcc.vol_reduce; 527 oth <<= 16; 528 oth |= net->cc_mod.rtcc.step_cnt; 529 oth <<= 16; 530 oth |= net->cc_mod.rtcc.last_step_state; 531 SDT_PROBE(sctp, cwnd, net, rttstep, 532 vtag, 533 ((net->cc_mod.rtcc.lbw << 32) | nbw), 534 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 535 oth, 536 probepoint); 537 net->cc_mod.rtcc.last_step_state = 0; 538 net->cc_mod.rtcc.step_cnt = 0; 539 net->cc_mod.rtcc.vol_reduce = 0; 540 } 541 net->cc_mod.rtcc.lbw = nbw; 542 net->cc_mod.rtcc.lbw_rtt = net->rtt; 543 net->cc_mod.rtcc.cwnd_at_bw_set = net->cwnd; 544 return (0); 545} 546 547/* RTCC Algoritm to limit growth of cwnd, return 548 * true if you want to NOT allow cwnd growth 549 */ 550static int 551cc_bw_limit(struct sctp_tcb *stcb, struct sctp_nets *net, uint64_t nbw) 552{ 553 uint64_t bw_offset, rtt_offset; 554 uint64_t probepoint, rtt, vtag; 555 uint64_t bytes_for_this_rtt, inst_bw; 556 uint64_t div, inst_off; 557 int bw_shift; 558 uint8_t inst_ind; 559 int ret; 560 561 /*- 562 * Here we need to see if we want 563 * to limit cwnd growth due to increase 564 * in overall rtt but no increase in bw. 565 * We use the following table to figure 566 * out what we should do. When we return 567 * 0, cc update goes on as planned. If we 568 * return 1, then no cc update happens and cwnd 569 * stays where it is at. 570 * ---------------------------------- 571 * BW | RTT | Action 572 * ********************************* 573 * INC | INC | return 0 574 * ---------------------------------- 575 * INC | SAME | return 0 576 * ---------------------------------- 577 * INC | DECR | return 0 578 * ---------------------------------- 579 * SAME | INC | return 1 580 * ---------------------------------- 581 * SAME | SAME | return 1 582 * ---------------------------------- 583 * SAME | DECR | return 0 584 * ---------------------------------- 585 * DECR | INC | return 0 or 1 based on if we caused. 586 * ---------------------------------- 587 * DECR | SAME | return 0 588 * ---------------------------------- 589 * DECR | DECR | return 0 590 * ---------------------------------- 591 * 592 * We are a bit fuzz on what an increase or 593 * decrease is. For BW it is the same if 594 * it did not change within 1/64th. For 595 * RTT it stayed the same if it did not 596 * change within 1/32nd 597 */ 598 bw_shift = SCTP_BASE_SYSCTL(sctp_rttvar_bw); 599 rtt = stcb->asoc.my_vtag; 600 vtag = (rtt << 32) | (((uint32_t) (stcb->sctp_ep->sctp_lport)) << 16) | (stcb->rport); 601 probepoint = (((uint64_t) net->cwnd) << 32); 602 rtt = net->rtt; 603 if (net->cc_mod.rtcc.rtt_set_this_sack) { 604 net->cc_mod.rtcc.rtt_set_this_sack = 0; 605 bytes_for_this_rtt = net->cc_mod.rtcc.bw_bytes - net->cc_mod.rtcc.bw_bytes_at_last_rttc; 606 net->cc_mod.rtcc.bw_bytes_at_last_rttc = net->cc_mod.rtcc.bw_bytes; 607 if (net->rtt) { 608 div = net->rtt / 1000; 609 if (div) { 610 inst_bw = bytes_for_this_rtt / div; 611 inst_off = inst_bw >> bw_shift; 612 if (inst_bw > nbw) 613 inst_ind = SCTP_INST_GAINING; 614 else if ((inst_bw + inst_off) < nbw) 615 inst_ind = SCTP_INST_LOOSING; 616 else 617 inst_ind = SCTP_INST_NEUTRAL; 618 probepoint |= ((0xb << 16) | inst_ind); 619 } else { 620 inst_ind = net->cc_mod.rtcc.last_inst_ind; 621 inst_bw = bytes_for_this_rtt / (uint64_t) (net->rtt); 622 /* Can't determine do not change */ 623 probepoint |= ((0xc << 16) | inst_ind); 624 } 625 } else { 626 inst_ind = net->cc_mod.rtcc.last_inst_ind; 627 inst_bw = bytes_for_this_rtt; 628 /* Can't determine do not change */ 629 probepoint |= ((0xd << 16) | inst_ind); 630 } 631 SDT_PROBE(sctp, cwnd, net, rttvar, 632 vtag, 633 ((nbw << 32) | inst_bw), 634 ((net->cc_mod.rtcc.lbw_rtt << 32) | rtt), 635 net->flight_size, 636 probepoint); 637 } else { 638 /* No rtt measurement, use last one */ 639 inst_ind = net->cc_mod.rtcc.last_inst_ind; 640 } 641 bw_offset = net->cc_mod.rtcc.lbw >> bw_shift; 642 if (nbw > net->cc_mod.rtcc.lbw + bw_offset) { 643 ret = cc_bw_increase(stcb, net, nbw, vtag); 644 goto out; 645 } 646 rtt_offset = net->cc_mod.rtcc.lbw_rtt >> SCTP_BASE_SYSCTL(sctp_rttvar_rtt); 647 if (nbw < net->cc_mod.rtcc.lbw - bw_offset) { 648 ret = cc_bw_decrease(stcb, net, nbw, rtt_offset, vtag, inst_ind); 649 goto out; 650 } 651 /* 652 * If we reach here then we are in a situation where the bw stayed 653 * the same. 654 */ 655 ret = cc_bw_same(stcb, net, nbw, rtt_offset, vtag, inst_ind); 656out: 657 net->cc_mod.rtcc.last_inst_ind = inst_ind; 658 return (ret); 659} 660 661static void 662sctp_cwnd_update_after_sack_common(struct sctp_tcb *stcb, 663 struct sctp_association *asoc, 664 int accum_moved, int reneged_all SCTP_UNUSED, int will_exit, int use_rtcc) 665{ 666 struct sctp_nets *net; 667 int old_cwnd; 668 uint32_t t_ssthresh, t_cwnd, incr; 669 uint64_t t_ucwnd_sbw; 670 uint64_t t_path_mptcp; 671 uint64_t mptcp_like_alpha; 672 uint32_t srtt; 673 uint64_t max_path; 674 675 /* MT FIXME: Don't compute this over and over again */ 676 t_ssthresh = 0; 677 t_cwnd = 0; 678 t_ucwnd_sbw = 0; 679 t_path_mptcp = 0; 680 mptcp_like_alpha = 1; 681 if ((stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV1) || 682 (stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV2) || 683 (stcb->asoc.sctp_cmt_on_off == SCTP_CMT_MPTCP)) { 684 max_path = 0; 685 TAILQ_FOREACH(net, &stcb->asoc.nets, sctp_next) { 686 t_ssthresh += net->ssthresh; 687 t_cwnd += net->cwnd; 688 /* lastsa>>3; we don't need to devide ... */ 689 srtt = net->lastsa; 690 if (srtt > 0) { 691 uint64_t tmp; 692 693 t_ucwnd_sbw += (uint64_t) net->cwnd / (uint64_t) srtt; 694 t_path_mptcp += (((uint64_t) net->cwnd) << SHIFT_MPTCP_MULTI_Z) / 695 (((uint64_t) net->mtu) * (uint64_t) srtt); 696 tmp = (((uint64_t) net->cwnd) << SHIFT_MPTCP_MULTI_N) / 697 ((uint64_t) net->mtu * (uint64_t) (srtt * srtt)); 698 if (tmp > max_path) { 699 max_path = tmp; 700 } 701 } 702 } 703 if (t_path_mptcp > 0) { 704 mptcp_like_alpha = max_path / (t_path_mptcp * t_path_mptcp); 705 } else { 706 mptcp_like_alpha = 1; 707 } 708 } 709 if (t_ssthresh == 0) { 710 t_ssthresh = 1; 711 } 712 if (t_ucwnd_sbw == 0) { 713 t_ucwnd_sbw = 1; 714 } 715 /******************************/ 716 /* update cwnd and Early FR */ 717 /******************************/ 718 TAILQ_FOREACH(net, &asoc->nets, sctp_next) { 719 720#ifdef JANA_CMT_FAST_RECOVERY 721 /* 722 * CMT fast recovery code. Need to debug. 723 */ 724 if (net->fast_retran_loss_recovery && net->new_pseudo_cumack) { 725 if (SCTP_TSN_GE(asoc->last_acked_seq, net->fast_recovery_tsn) || 726 SCTP_TSN_GE(net->pseudo_cumack, net->fast_recovery_tsn)) { 727 net->will_exit_fast_recovery = 1; 728 } 729 } 730#endif 731 /* if nothing was acked on this destination skip it */ 732 if (net->net_ack == 0) { 733 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) { 734 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_LOG_FROM_SACK); 735 } 736 continue; 737 } 738#ifdef JANA_CMT_FAST_RECOVERY 739 /* 740 * CMT fast recovery code 741 */ 742 /* 743 * if (sctp_cmt_on_off > 0 && net->fast_retran_loss_recovery 744 * && net->will_exit_fast_recovery == 0) { @@@ Do something 745 * } else if (sctp_cmt_on_off == 0 && 746 * asoc->fast_retran_loss_recovery && will_exit == 0) { 747 */ 748#endif 749 750 if (asoc->fast_retran_loss_recovery && 751 (will_exit == 0) && 752 (asoc->sctp_cmt_on_off == 0)) { 753 /* 754 * If we are in loss recovery we skip any cwnd 755 * update 756 */ 757 return; 758 } 759 /* 760 * Did any measurements go on for this network? 761 */ 762 if (use_rtcc && (net->cc_mod.rtcc.tls_needs_set > 0)) { 763 uint64_t nbw; 764 765 /* 766 * At this point our bw_bytes has been updated by 767 * incoming sack information. 768 * 769 * But our bw may not yet be set. 770 * 771 */ 772 if ((net->cc_mod.rtcc.new_tot_time / 1000) > 0) { 773 nbw = net->cc_mod.rtcc.bw_bytes / (net->cc_mod.rtcc.new_tot_time / 1000); 774 } else { 775 nbw = net->cc_mod.rtcc.bw_bytes; 776 } 777 if (net->cc_mod.rtcc.lbw) { 778 if (cc_bw_limit(stcb, net, nbw)) { 779 /* Hold here, no update */ 780 continue; 781 } 782 } else { 783 uint64_t vtag, probepoint; 784 785 probepoint = (((uint64_t) net->cwnd) << 32); 786 probepoint |= ((0xa << 16) | 0); 787 vtag = (net->rtt << 32) | 788 (((uint32_t) (stcb->sctp_ep->sctp_lport)) << 16) | 789 (stcb->rport); 790 791 SDT_PROBE(sctp, cwnd, net, rttvar, 792 vtag, 793 nbw, 794 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 795 net->flight_size, 796 probepoint); 797 net->cc_mod.rtcc.lbw = nbw; 798 net->cc_mod.rtcc.lbw_rtt = net->rtt; 799 if (net->cc_mod.rtcc.rtt_set_this_sack) { 800 net->cc_mod.rtcc.rtt_set_this_sack = 0; 801 net->cc_mod.rtcc.bw_bytes_at_last_rttc = net->cc_mod.rtcc.bw_bytes; 802 } 803 } 804 } 805 /* 806 * CMT: CUC algorithm. Update cwnd if pseudo-cumack has 807 * moved. 808 */ 809 if (accum_moved || 810 ((asoc->sctp_cmt_on_off > 0) && net->new_pseudo_cumack)) { 811 /* If the cumulative ack moved we can proceed */ 812 if (net->cwnd <= net->ssthresh) { 813 /* We are in slow start */ 814 if (net->flight_size + net->net_ack >= net->cwnd) { 815 uint32_t limit; 816 817 old_cwnd = net->cwnd; 818 switch (asoc->sctp_cmt_on_off) { 819 case SCTP_CMT_RPV1: 820 limit = (uint32_t) (((uint64_t) net->mtu * 821 (uint64_t) SCTP_BASE_SYSCTL(sctp_L2_abc_variable) * 822 (uint64_t) net->ssthresh) / 823 (uint64_t) t_ssthresh); 824 incr = (uint32_t) (((uint64_t) net->net_ack * 825 (uint64_t) net->ssthresh) / 826 (uint64_t) t_ssthresh); 827 if (incr > limit) { 828 incr = limit; 829 } 830 if (incr == 0) { 831 incr = 1; 832 } 833 break; 834 case SCTP_CMT_RPV2: 835 /* 836 * lastsa>>3; we don't need 837 * to divide ... 838 */ 839 srtt = net->lastsa; 840 if (srtt == 0) { 841 srtt = 1; 842 } 843 limit = (uint32_t) (((uint64_t) net->mtu * 844 (uint64_t) SCTP_BASE_SYSCTL(sctp_L2_abc_variable) * 845 (uint64_t) net->cwnd) / 846 ((uint64_t) srtt * t_ucwnd_sbw)); 847 /* INCREASE FACTOR */ 848 incr = (uint32_t) (((uint64_t) net->net_ack * 849 (uint64_t) net->cwnd) / 850 ((uint64_t) srtt * t_ucwnd_sbw)); 851 /* INCREASE FACTOR */ 852 if (incr > limit) { 853 incr = limit; 854 } 855 if (incr == 0) { 856 incr = 1; 857 } 858 break; 859 case SCTP_CMT_MPTCP: 860 limit = (uint32_t) (((uint64_t) net->mtu * 861 mptcp_like_alpha * 862 (uint64_t) SCTP_BASE_SYSCTL(sctp_L2_abc_variable)) >> 863 SHIFT_MPTCP_MULTI); 864 incr = (uint32_t) (((uint64_t) net->net_ack * 865 mptcp_like_alpha) >> 866 SHIFT_MPTCP_MULTI); 867 if (incr > limit) { 868 incr = limit; 869 } 870 if (incr > net->net_ack) { 871 incr = net->net_ack; 872 } 873 if (incr > net->mtu) { 874 incr = net->mtu; 875 } 876 break; 877 default: 878 incr = net->net_ack; 879 if (incr > net->mtu * SCTP_BASE_SYSCTL(sctp_L2_abc_variable)) { 880 incr = net->mtu * SCTP_BASE_SYSCTL(sctp_L2_abc_variable); 881 } 882 break; 883 } 884 net->cwnd += incr; 885 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 886 sctp_log_cwnd(stcb, net, incr, 887 SCTP_CWND_LOG_FROM_SS); 888 } 889 SDT_PROBE(sctp, cwnd, net, ack, 890 stcb->asoc.my_vtag, 891 ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)), 892 net, 893 old_cwnd, net->cwnd); 894 } else { 895 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) { 896 sctp_log_cwnd(stcb, net, net->net_ack, 897 SCTP_CWND_LOG_NOADV_SS); 898 } 899 } 900 } else { 901 /* We are in congestion avoidance */ 902 /* 903 * Add to pba 904 */ 905 net->partial_bytes_acked += net->net_ack; 906 907 if ((net->flight_size + net->net_ack >= net->cwnd) && 908 (net->partial_bytes_acked >= net->cwnd)) { 909 net->partial_bytes_acked -= net->cwnd; 910 old_cwnd = net->cwnd; 911 switch (asoc->sctp_cmt_on_off) { 912 case SCTP_CMT_RPV1: 913 incr = (uint32_t) (((uint64_t) net->mtu * 914 (uint64_t) net->ssthresh) / 915 (uint64_t) t_ssthresh); 916 if (incr == 0) { 917 incr = 1; 918 } 919 break; 920 case SCTP_CMT_RPV2: 921 /* 922 * lastsa>>3; we don't need 923 * to divide ... 924 */ 925 srtt = net->lastsa; 926 if (srtt == 0) { 927 srtt = 1; 928 } 929 incr = (uint32_t) ((uint64_t) net->mtu * 930 (uint64_t) net->cwnd / 931 ((uint64_t) srtt * 932 t_ucwnd_sbw)); 933 /* INCREASE FACTOR */ 934 if (incr == 0) { 935 incr = 1; 936 } 937 break; 938 case SCTP_CMT_MPTCP: 939 incr = (uint32_t) ((mptcp_like_alpha * 940 (uint64_t) net->cwnd) >> 941 SHIFT_MPTCP_MULTI); 942 if (incr > net->mtu) { 943 incr = net->mtu; 944 } 945 break; 946 default: 947 incr = net->mtu; 948 break; 949 } 950 net->cwnd += incr; 951 SDT_PROBE(sctp, cwnd, net, ack, 952 stcb->asoc.my_vtag, 953 ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)), 954 net, 955 old_cwnd, net->cwnd); 956 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 957 sctp_log_cwnd(stcb, net, net->mtu, 958 SCTP_CWND_LOG_FROM_CA); 959 } 960 } else { 961 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) { 962 sctp_log_cwnd(stcb, net, net->net_ack, 963 SCTP_CWND_LOG_NOADV_CA); 964 } 965 } 966 } 967 } else { 968 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) { 969 sctp_log_cwnd(stcb, net, net->mtu, 970 SCTP_CWND_LOG_NO_CUMACK); 971 } 972 } 973 } 974} 975 976static void 977sctp_cwnd_update_exit_pf_common(struct sctp_tcb *stcb, struct sctp_nets *net) 978{ 979 int old_cwnd; 980 981 old_cwnd = net->cwnd; 982 net->cwnd = net->mtu; 983 SDT_PROBE(sctp, cwnd, net, ack, 984 stcb->asoc.my_vtag, ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)), net, 985 old_cwnd, net->cwnd); 986 SCTPDBG(SCTP_DEBUG_INDATA1, "Destination %p moved from PF to reachable with cwnd %d.\n", 987 (void *)net, net->cwnd); 988} 989 990 991static void 992sctp_cwnd_update_after_timeout(struct sctp_tcb *stcb, struct sctp_nets *net) 993{ 994 int old_cwnd = net->cwnd; 995 uint32_t t_ssthresh, t_cwnd; 996 uint64_t t_ucwnd_sbw; 997 998 /* MT FIXME: Don't compute this over and over again */ 999 t_ssthresh = 0; 1000 t_cwnd = 0; 1001 if ((stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV1) || 1002 (stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV2)) { 1003 struct sctp_nets *lnet; 1004 uint32_t srtt; 1005 1006 t_ucwnd_sbw = 0; 1007 TAILQ_FOREACH(lnet, &stcb->asoc.nets, sctp_next) { 1008 t_ssthresh += lnet->ssthresh; 1009 t_cwnd += lnet->cwnd; 1010 srtt = lnet->lastsa; 1011 /* lastsa>>3; we don't need to divide ... */ 1012 if (srtt > 0) { 1013 t_ucwnd_sbw += (uint64_t) lnet->cwnd / (uint64_t) srtt; 1014 } 1015 } 1016 if (t_ssthresh < 1) { 1017 t_ssthresh = 1; 1018 } 1019 if (t_ucwnd_sbw < 1) { 1020 t_ucwnd_sbw = 1; 1021 } 1022 if (stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV1) { 1023 net->ssthresh = (uint32_t) (((uint64_t) 4 * 1024 (uint64_t) net->mtu * 1025 (uint64_t) net->ssthresh) / 1026 (uint64_t) t_ssthresh); 1027 } else { 1028 uint64_t cc_delta; 1029 1030 srtt = net->lastsa; 1031 /* lastsa>>3; we don't need to divide ... */ 1032 if (srtt == 0) { 1033 srtt = 1; 1034 } 1035 cc_delta = t_ucwnd_sbw * (uint64_t) srtt / 2; 1036 if (cc_delta < t_cwnd) { 1037 net->ssthresh = (uint32_t) ((uint64_t) t_cwnd - cc_delta); 1038 } else { 1039 net->ssthresh = net->mtu; 1040 } 1041 } 1042 if ((net->cwnd > t_cwnd / 2) && 1043 (net->ssthresh < net->cwnd - t_cwnd / 2)) { 1044 net->ssthresh = net->cwnd - t_cwnd / 2; 1045 } 1046 if (net->ssthresh < net->mtu) { 1047 net->ssthresh = net->mtu; 1048 } 1049 } else { 1050 net->ssthresh = max(net->cwnd / 2, 4 * net->mtu); 1051 } 1052 net->cwnd = net->mtu; 1053 net->partial_bytes_acked = 0; 1054 SDT_PROBE(sctp, cwnd, net, to, 1055 stcb->asoc.my_vtag, 1056 ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)), 1057 net, 1058 old_cwnd, net->cwnd); 1059 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 1060 sctp_log_cwnd(stcb, net, net->cwnd - old_cwnd, SCTP_CWND_LOG_FROM_RTX); 1061 } 1062} 1063 1064static void 1065sctp_cwnd_update_after_ecn_echo_common(struct sctp_tcb *stcb, struct sctp_nets *net, 1066 int in_window, int num_pkt_lost, int use_rtcc) 1067{ 1068 int old_cwnd = net->cwnd; 1069 1070 if ((use_rtcc) && (net->lan_type == SCTP_LAN_LOCAL) && (net->cc_mod.rtcc.use_dccc_ecn)) { 1071 /* Data center Congestion Control */ 1072 if (in_window == 0) { 1073 /* 1074 * Go to CA with the cwnd at the point we sent the 1075 * TSN that was marked with a CE. 1076 */ 1077 if (net->ecn_prev_cwnd < net->cwnd) { 1078 /* Restore to prev cwnd */ 1079 net->cwnd = net->ecn_prev_cwnd - (net->mtu * num_pkt_lost); 1080 } else { 1081 /* Just cut in 1/2 */ 1082 net->cwnd /= 2; 1083 } 1084 /* Drop to CA */ 1085 net->ssthresh = net->cwnd - (num_pkt_lost * net->mtu); 1086 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 1087 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT); 1088 } 1089 } else { 1090 /* 1091 * Further tuning down required over the drastic 1092 * orginal cut 1093 */ 1094 net->ssthresh -= (net->mtu * num_pkt_lost); 1095 net->cwnd -= (net->mtu * num_pkt_lost); 1096 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 1097 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT); 1098 } 1099 } 1100 SCTP_STAT_INCR(sctps_ecnereducedcwnd); 1101 } else { 1102 if (in_window == 0) { 1103 SCTP_STAT_INCR(sctps_ecnereducedcwnd); 1104 net->ssthresh = net->cwnd / 2; 1105 if (net->ssthresh < net->mtu) { 1106 net->ssthresh = net->mtu; 1107 /* 1108 * here back off the timer as well, to slow 1109 * us down 1110 */ 1111 net->RTO <<= 1; 1112 } 1113 net->cwnd = net->ssthresh; 1114 SDT_PROBE(sctp, cwnd, net, ecn, 1115 stcb->asoc.my_vtag, 1116 ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)), 1117 net, 1118 old_cwnd, net->cwnd); 1119 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 1120 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT); 1121 } 1122 } 1123 } 1124 1125} 1126 1127static void 1128sctp_cwnd_update_after_packet_dropped(struct sctp_tcb *stcb, 1129 struct sctp_nets *net, struct sctp_pktdrop_chunk *cp, 1130 uint32_t * bottle_bw, uint32_t * on_queue) 1131{ 1132 uint32_t bw_avail; 1133 unsigned int incr; 1134 int old_cwnd = net->cwnd; 1135 1136 /* get bottle neck bw */ 1137 *bottle_bw = ntohl(cp->bottle_bw); 1138 /* and whats on queue */ 1139 *on_queue = ntohl(cp->current_onq); 1140 /* 1141 * adjust the on-queue if our flight is more it could be that the 1142 * router has not yet gotten data "in-flight" to it 1143 */ 1144 if (*on_queue < net->flight_size) { 1145 *on_queue = net->flight_size; 1146 } 1147 /* rtt is measured in micro seconds, bottle_bw in bytes per second */ 1148 bw_avail = (uint32_t) (((uint64_t) (*bottle_bw) * net->rtt) / (uint64_t) 1000000); 1149 if (bw_avail > *bottle_bw) { 1150 /* 1151 * Cap the growth to no more than the bottle neck. This can 1152 * happen as RTT slides up due to queues. It also means if 1153 * you have more than a 1 second RTT with a empty queue you 1154 * will be limited to the bottle_bw per second no matter if 1155 * other points have 1/2 the RTT and you could get more 1156 * out... 1157 */ 1158 bw_avail = *bottle_bw; 1159 } 1160 if (*on_queue > bw_avail) { 1161 /* 1162 * No room for anything else don't allow anything else to be 1163 * "added to the fire". 1164 */ 1165 int seg_inflight, seg_onqueue, my_portion; 1166 1167 net->partial_bytes_acked = 0; 1168 /* how much are we over queue size? */ 1169 incr = *on_queue - bw_avail; 1170 if (stcb->asoc.seen_a_sack_this_pkt) { 1171 /* 1172 * undo any cwnd adjustment that the sack might have 1173 * made 1174 */ 1175 net->cwnd = net->prev_cwnd; 1176 } 1177 /* Now how much of that is mine? */ 1178 seg_inflight = net->flight_size / net->mtu; 1179 seg_onqueue = *on_queue / net->mtu; 1180 my_portion = (incr * seg_inflight) / seg_onqueue; 1181 1182 /* Have I made an adjustment already */ 1183 if (net->cwnd > net->flight_size) { 1184 /* 1185 * for this flight I made an adjustment we need to 1186 * decrease the portion by a share our previous 1187 * adjustment. 1188 */ 1189 int diff_adj; 1190 1191 diff_adj = net->cwnd - net->flight_size; 1192 if (diff_adj > my_portion) 1193 my_portion = 0; 1194 else 1195 my_portion -= diff_adj; 1196 } 1197 /* 1198 * back down to the previous cwnd (assume we have had a sack 1199 * before this packet). minus what ever portion of the 1200 * overage is my fault. 1201 */ 1202 net->cwnd -= my_portion; 1203 1204 /* we will NOT back down more than 1 MTU */ 1205 if (net->cwnd <= net->mtu) { 1206 net->cwnd = net->mtu; 1207 } 1208 /* force into CA */ 1209 net->ssthresh = net->cwnd - 1; 1210 } else { 1211 /* 1212 * Take 1/4 of the space left or max burst up .. whichever 1213 * is less. 1214 */ 1215 incr = (bw_avail - *on_queue) >> 2; 1216 if ((stcb->asoc.max_burst > 0) && 1217 (stcb->asoc.max_burst * net->mtu < incr)) { 1218 incr = stcb->asoc.max_burst * net->mtu; 1219 } 1220 net->cwnd += incr; 1221 } 1222 if (net->cwnd > bw_avail) { 1223 /* We can't exceed the pipe size */ 1224 net->cwnd = bw_avail; 1225 } 1226 if (net->cwnd < net->mtu) { 1227 /* We always have 1 MTU */ 1228 net->cwnd = net->mtu; 1229 } 1230 if (net->cwnd - old_cwnd != 0) { 1231 /* log only changes */ 1232 SDT_PROBE(sctp, cwnd, net, pd, 1233 stcb->asoc.my_vtag, 1234 ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)), 1235 net, 1236 old_cwnd, net->cwnd); 1237 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 1238 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), 1239 SCTP_CWND_LOG_FROM_SAT); 1240 } 1241 } 1242} 1243 1244static void 1245sctp_cwnd_update_after_output(struct sctp_tcb *stcb, 1246 struct sctp_nets *net, int burst_limit) 1247{ 1248 int old_cwnd = net->cwnd; 1249 1250 if (net->ssthresh < net->cwnd) 1251 net->ssthresh = net->cwnd; 1252 if (burst_limit) { 1253 net->cwnd = (net->flight_size + (burst_limit * net->mtu)); 1254 SDT_PROBE(sctp, cwnd, net, bl, 1255 stcb->asoc.my_vtag, 1256 ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)), 1257 net, 1258 old_cwnd, net->cwnd); 1259 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 1260 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_BRST); 1261 } 1262 } 1263} 1264 1265static void 1266sctp_cwnd_update_after_sack(struct sctp_tcb *stcb, 1267 struct sctp_association *asoc, 1268 int accum_moved, int reneged_all, int will_exit) 1269{ 1270 /* Passing a zero argument in last disables the rtcc algoritm */ 1271 sctp_cwnd_update_after_sack_common(stcb, asoc, accum_moved, reneged_all, will_exit, 0); 1272} 1273 1274static void 1275sctp_cwnd_update_after_ecn_echo(struct sctp_tcb *stcb, struct sctp_nets *net, 1276 int in_window, int num_pkt_lost) 1277{ 1278 /* Passing a zero argument in last disables the rtcc algoritm */ 1279 sctp_cwnd_update_after_ecn_echo_common(stcb, net, in_window, num_pkt_lost, 0); 1280} 1281 1282/* Here starts the RTCCVAR type CC invented by RRS which 1283 * is a slight mod to RFC2581. We reuse a common routine or 1284 * two since these algoritms are so close and need to 1285 * remain the same. 1286 */ 1287static void 1288sctp_cwnd_update_rtcc_after_ecn_echo(struct sctp_tcb *stcb, struct sctp_nets *net, 1289 int in_window, int num_pkt_lost) 1290{ 1291 sctp_cwnd_update_after_ecn_echo_common(stcb, net, in_window, num_pkt_lost, 1); 1292} 1293 1294 1295static 1296void 1297sctp_cwnd_update_rtcc_tsn_acknowledged(struct sctp_nets *net, 1298 struct sctp_tmit_chunk *tp1) 1299{ 1300 net->cc_mod.rtcc.bw_bytes += tp1->send_size; 1301} 1302 1303static void 1304sctp_cwnd_prepare_rtcc_net_for_sack(struct sctp_tcb *stcb SCTP_UNUSED, 1305 struct sctp_nets *net) 1306{ 1307 if (net->cc_mod.rtcc.tls_needs_set > 0) { 1308 /* We had a bw measurment going on */ 1309 struct timeval ltls; 1310 1311 SCTP_GETPTIME_TIMEVAL(<ls); 1312 timevalsub(<ls, &net->cc_mod.rtcc.tls); 1313 net->cc_mod.rtcc.new_tot_time = (ltls.tv_sec * 1000000) + ltls.tv_usec; 1314 } 1315} 1316 1317static void 1318sctp_cwnd_new_rtcc_transmission_begins(struct sctp_tcb *stcb, 1319 struct sctp_nets *net) 1320{ 1321 uint64_t vtag, probepoint; 1322 1323 if (net->cc_mod.rtcc.lbw) { 1324 /* Clear the old bw.. we went to 0 in-flight */ 1325 vtag = (net->rtt << 32) | (((uint32_t) (stcb->sctp_ep->sctp_lport)) << 16) | 1326 (stcb->rport); 1327 probepoint = (((uint64_t) net->cwnd) << 32); 1328 /* Probe point 8 */ 1329 probepoint |= ((8 << 16) | 0); 1330 SDT_PROBE(sctp, cwnd, net, rttvar, 1331 vtag, 1332 ((net->cc_mod.rtcc.lbw << 32) | 0), 1333 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 1334 net->flight_size, 1335 probepoint); 1336 net->cc_mod.rtcc.lbw_rtt = 0; 1337 net->cc_mod.rtcc.cwnd_at_bw_set = 0; 1338 net->cc_mod.rtcc.lbw = 0; 1339 net->cc_mod.rtcc.bw_bytes_at_last_rttc = 0; 1340 net->cc_mod.rtcc.vol_reduce = 0; 1341 net->cc_mod.rtcc.bw_tot_time = 0; 1342 net->cc_mod.rtcc.bw_bytes = 0; 1343 net->cc_mod.rtcc.tls_needs_set = 0; 1344 if (net->cc_mod.rtcc.steady_step) { 1345 net->cc_mod.rtcc.vol_reduce = 0; 1346 net->cc_mod.rtcc.step_cnt = 0; 1347 net->cc_mod.rtcc.last_step_state = 0; 1348 } 1349 if (net->cc_mod.rtcc.ret_from_eq) { 1350 /* less aggressive one - reset cwnd too */ 1351 uint32_t cwnd_in_mtu, cwnd; 1352 1353 cwnd_in_mtu = SCTP_BASE_SYSCTL(sctp_initial_cwnd); 1354 if (cwnd_in_mtu == 0) { 1355 /* 1356 * Using 0 means that the value of RFC 4960 1357 * is used. 1358 */ 1359 cwnd = min((net->mtu * 4), max((2 * net->mtu), SCTP_INITIAL_CWND)); 1360 } else { 1361 /* 1362 * We take the minimum of the burst limit 1363 * and the initial congestion window. 1364 */ 1365 if ((stcb->asoc.max_burst > 0) && (cwnd_in_mtu > stcb->asoc.max_burst)) 1366 cwnd_in_mtu = stcb->asoc.max_burst; 1367 cwnd = (net->mtu - sizeof(struct sctphdr)) * cwnd_in_mtu; 1368 } 1369 if (net->cwnd > cwnd) { 1370 /* 1371 * Only set if we are not a timeout (i.e. 1372 * down to 1 mtu) 1373 */ 1374 net->cwnd = cwnd; 1375 } 1376 } 1377 } 1378} 1379 1380static void 1381sctp_set_rtcc_initial_cc_param(struct sctp_tcb *stcb, 1382 struct sctp_nets *net) 1383{ 1384 uint64_t vtag, probepoint; 1385 1386 sctp_set_initial_cc_param(stcb, net); 1387 stcb->asoc.use_precise_time = 1; 1388 probepoint = (((uint64_t) net->cwnd) << 32); 1389 probepoint |= ((9 << 16) | 0); 1390 vtag = (net->rtt << 32) | 1391 (((uint32_t) (stcb->sctp_ep->sctp_lport)) << 16) | 1392 (stcb->rport); 1393 SDT_PROBE(sctp, cwnd, net, rttvar, 1394 vtag, 1395 0, 1396 0, 1397 0, 1398 probepoint); 1399 net->cc_mod.rtcc.lbw_rtt = 0; 1400 net->cc_mod.rtcc.cwnd_at_bw_set = 0; 1401 net->cc_mod.rtcc.vol_reduce = 0; 1402 net->cc_mod.rtcc.lbw = 0; 1403 net->cc_mod.rtcc.vol_reduce = 0; 1404 net->cc_mod.rtcc.bw_bytes_at_last_rttc = 0; 1405 net->cc_mod.rtcc.bw_tot_time = 0; 1406 net->cc_mod.rtcc.bw_bytes = 0; 1407 net->cc_mod.rtcc.tls_needs_set = 0; 1408 net->cc_mod.rtcc.ret_from_eq = SCTP_BASE_SYSCTL(sctp_rttvar_eqret); 1409 net->cc_mod.rtcc.steady_step = SCTP_BASE_SYSCTL(sctp_steady_step); 1410 net->cc_mod.rtcc.use_dccc_ecn = SCTP_BASE_SYSCTL(sctp_use_dccc_ecn); 1411 net->cc_mod.rtcc.step_cnt = 0; 1412 net->cc_mod.rtcc.last_step_state = 0; 1413 1414 1415} 1416 1417static int 1418sctp_cwnd_rtcc_socket_option(struct sctp_tcb *stcb, int setorget, 1419 struct sctp_cc_option *cc_opt) 1420{ 1421 struct sctp_nets *net; 1422 1423 if (setorget == 1) { 1424 /* a set */ 1425 if (cc_opt->option == SCTP_CC_OPT_RTCC_SETMODE) { 1426 if ((cc_opt->aid_value.assoc_value != 0) && 1427 (cc_opt->aid_value.assoc_value != 1)) { 1428 return (EINVAL); 1429 } 1430 TAILQ_FOREACH(net, &stcb->asoc.nets, sctp_next) { 1431 net->cc_mod.rtcc.ret_from_eq = cc_opt->aid_value.assoc_value; 1432 } 1433 } else if (cc_opt->option == SCTP_CC_OPT_USE_DCCC_ECN) { 1434 if ((cc_opt->aid_value.assoc_value != 0) && 1435 (cc_opt->aid_value.assoc_value != 1)) { 1436 return (EINVAL); 1437 } 1438 TAILQ_FOREACH(net, &stcb->asoc.nets, sctp_next) { 1439 net->cc_mod.rtcc.use_dccc_ecn = cc_opt->aid_value.assoc_value; 1440 } 1441 } else if (cc_opt->option == SCTP_CC_OPT_STEADY_STEP) { 1442 TAILQ_FOREACH(net, &stcb->asoc.nets, sctp_next) { 1443 net->cc_mod.rtcc.steady_step = cc_opt->aid_value.assoc_value; 1444 } 1445 } else { 1446 return (EINVAL); 1447 } 1448 } else { 1449 /* a get */ 1450 if (cc_opt->option == SCTP_CC_OPT_RTCC_SETMODE) { 1451 net = TAILQ_FIRST(&stcb->asoc.nets); 1452 if (net == NULL) { 1453 return (EFAULT); 1454 } 1455 cc_opt->aid_value.assoc_value = net->cc_mod.rtcc.ret_from_eq; 1456 } else if (cc_opt->option == SCTP_CC_OPT_USE_DCCC_ECN) { 1457 net = TAILQ_FIRST(&stcb->asoc.nets); 1458 if (net == NULL) { 1459 return (EFAULT); 1460 } 1461 cc_opt->aid_value.assoc_value = net->cc_mod.rtcc.use_dccc_ecn; 1462 } else if (cc_opt->option == SCTP_CC_OPT_STEADY_STEP) { 1463 net = TAILQ_FIRST(&stcb->asoc.nets); 1464 if (net == NULL) { 1465 return (EFAULT); 1466 } 1467 cc_opt->aid_value.assoc_value = net->cc_mod.rtcc.steady_step; 1468 } else { 1469 return (EINVAL); 1470 } 1471 } 1472 return (0); 1473} 1474 1475static void 1476sctp_cwnd_update_rtcc_packet_transmitted(struct sctp_tcb *stcb SCTP_UNUSED, 1477 struct sctp_nets *net) 1478{ 1479 if (net->cc_mod.rtcc.tls_needs_set == 0) { 1480 SCTP_GETPTIME_TIMEVAL(&net->cc_mod.rtcc.tls); 1481 net->cc_mod.rtcc.tls_needs_set = 2; 1482 } 1483} 1484 1485static void 1486sctp_cwnd_update_rtcc_after_sack(struct sctp_tcb *stcb, 1487 struct sctp_association *asoc, 1488 int accum_moved, int reneged_all, int will_exit) 1489{ 1490 /* Passing a one argument at the last enables the rtcc algoritm */ 1491 sctp_cwnd_update_after_sack_common(stcb, asoc, accum_moved, reneged_all, will_exit, 1); 1492} 1493 1494static void 1495sctp_rtt_rtcc_calculated(struct sctp_tcb *stcb SCTP_UNUSED, 1496 struct sctp_nets *net, 1497 struct timeval *now SCTP_UNUSED) 1498{ 1499 net->cc_mod.rtcc.rtt_set_this_sack = 1; 1500} 1501 1502/* Here starts Sally Floyds HS-TCP */ 1503 1504struct sctp_hs_raise_drop { 1505 int32_t cwnd; 1506 int32_t increase; 1507 int32_t drop_percent; 1508}; 1509 1510#define SCTP_HS_TABLE_SIZE 73 1511 1512struct sctp_hs_raise_drop sctp_cwnd_adjust[SCTP_HS_TABLE_SIZE] = { 1513 {38, 1, 50}, /* 0 */ 1514 {118, 2, 44}, /* 1 */ 1515 {221, 3, 41}, /* 2 */ 1516 {347, 4, 38}, /* 3 */ 1517 {495, 5, 37}, /* 4 */ 1518 {663, 6, 35}, /* 5 */ 1519 {851, 7, 34}, /* 6 */ 1520 {1058, 8, 33}, /* 7 */ 1521 {1284, 9, 32}, /* 8 */ 1522 {1529, 10, 31}, /* 9 */ 1523 {1793, 11, 30}, /* 10 */ 1524 {2076, 12, 29}, /* 11 */ 1525 {2378, 13, 28}, /* 12 */ 1526 {2699, 14, 28}, /* 13 */ 1527 {3039, 15, 27}, /* 14 */ 1528 {3399, 16, 27}, /* 15 */ 1529 {3778, 17, 26}, /* 16 */ 1530 {4177, 18, 26}, /* 17 */ 1531 {4596, 19, 25}, /* 18 */ 1532 {5036, 20, 25}, /* 19 */ 1533 {5497, 21, 24}, /* 20 */ 1534 {5979, 22, 24}, /* 21 */ 1535 {6483, 23, 23}, /* 22 */ 1536 {7009, 24, 23}, /* 23 */ 1537 {7558, 25, 22}, /* 24 */ 1538 {8130, 26, 22}, /* 25 */ 1539 {8726, 27, 22}, /* 26 */ 1540 {9346, 28, 21}, /* 27 */ 1541 {9991, 29, 21}, /* 28 */ 1542 {10661, 30, 21}, /* 29 */ 1543 {11358, 31, 20}, /* 30 */ 1544 {12082, 32, 20}, /* 31 */ 1545 {12834, 33, 20}, /* 32 */ 1546 {13614, 34, 19}, /* 33 */ 1547 {14424, 35, 19}, /* 34 */ 1548 {15265, 36, 19}, /* 35 */ 1549 {16137, 37, 19}, /* 36 */ 1550 {17042, 38, 18}, /* 37 */ 1551 {17981, 39, 18}, /* 38 */ 1552 {18955, 40, 18}, /* 39 */ 1553 {19965, 41, 17}, /* 40 */ 1554 {21013, 42, 17}, /* 41 */ 1555 {22101, 43, 17}, /* 42 */ 1556 {23230, 44, 17}, /* 43 */ 1557 {24402, 45, 16}, /* 44 */ 1558 {25618, 46, 16}, /* 45 */ 1559 {26881, 47, 16}, /* 46 */ 1560 {28193, 48, 16}, /* 47 */ 1561 {29557, 49, 15}, /* 48 */ 1562 {30975, 50, 15}, /* 49 */ 1563 {32450, 51, 15}, /* 50 */ 1564 {33986, 52, 15}, /* 51 */ 1565 {35586, 53, 14}, /* 52 */ 1566 {37253, 54, 14}, /* 53 */ 1567 {38992, 55, 14}, /* 54 */ 1568 {40808, 56, 14}, /* 55 */ 1569 {42707, 57, 13}, /* 56 */ 1570 {44694, 58, 13}, /* 57 */ 1571 {46776, 59, 13}, /* 58 */ 1572 {48961, 60, 13}, /* 59 */ 1573 {51258, 61, 13}, /* 60 */ 1574 {53677, 62, 12}, /* 61 */ 1575 {56230, 63, 12}, /* 62 */ 1576 {58932, 64, 12}, /* 63 */ 1577 {61799, 65, 12}, /* 64 */ 1578 {64851, 66, 11}, /* 65 */ 1579 {68113, 67, 11}, /* 66 */ 1580 {71617, 68, 11}, /* 67 */ 1581 {75401, 69, 10}, /* 68 */ 1582 {79517, 70, 10}, /* 69 */ 1583 {84035, 71, 10}, /* 70 */ 1584 {89053, 72, 10}, /* 71 */ 1585 {94717, 73, 9} /* 72 */ 1586}; 1587 1588static void 1589sctp_hs_cwnd_increase(struct sctp_tcb *stcb, struct sctp_nets *net) 1590{ 1591 int cur_val, i, indx, incr; 1592 1593 cur_val = net->cwnd >> 10; 1594 indx = SCTP_HS_TABLE_SIZE - 1; 1595 1596 if (cur_val < sctp_cwnd_adjust[0].cwnd) { 1597 /* normal mode */ 1598 if (net->net_ack > net->mtu) { 1599 net->cwnd += net->mtu; 1600 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 1601 sctp_log_cwnd(stcb, net, net->mtu, SCTP_CWND_LOG_FROM_SS); 1602 } 1603 } else { 1604 net->cwnd += net->net_ack; 1605 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 1606 sctp_log_cwnd(stcb, net, net->net_ack, SCTP_CWND_LOG_FROM_SS); 1607 } 1608 } 1609 } else { 1610 for (i = net->last_hs_used; i < SCTP_HS_TABLE_SIZE; i++) { 1611 if (cur_val < sctp_cwnd_adjust[i].cwnd) { 1612 indx = i; 1613 break; 1614 } 1615 } 1616 net->last_hs_used = indx; 1617 incr = ((sctp_cwnd_adjust[indx].increase) << 10); 1618 net->cwnd += incr; 1619 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 1620 sctp_log_cwnd(stcb, net, incr, SCTP_CWND_LOG_FROM_SS); 1621 } 1622 } 1623} 1624 1625static void 1626sctp_hs_cwnd_decrease(struct sctp_tcb *stcb, struct sctp_nets *net) 1627{ 1628 int cur_val, i, indx; 1629 int old_cwnd = net->cwnd; 1630 1631 cur_val = net->cwnd >> 10; 1632 if (cur_val < sctp_cwnd_adjust[0].cwnd) { 1633 /* normal mode */ 1634 net->ssthresh = net->cwnd / 2; 1635 if (net->ssthresh < (net->mtu * 2)) { 1636 net->ssthresh = 2 * net->mtu; 1637 } 1638 net->cwnd = net->ssthresh; 1639 } else { 1640 /* drop by the proper amount */ 1641 net->ssthresh = net->cwnd - (int)((net->cwnd / 100) * 1642 sctp_cwnd_adjust[net->last_hs_used].drop_percent); 1643 net->cwnd = net->ssthresh; 1644 /* now where are we */ 1645 indx = net->last_hs_used; 1646 cur_val = net->cwnd >> 10; 1647 /* reset where we are in the table */ 1648 if (cur_val < sctp_cwnd_adjust[0].cwnd) { 1649 /* feel out of hs */ 1650 net->last_hs_used = 0; 1651 } else { 1652 for (i = indx; i >= 1; i--) { 1653 if (cur_val > sctp_cwnd_adjust[i - 1].cwnd) { 1654 break; 1655 } 1656 } 1657 net->last_hs_used = indx; 1658 } 1659 } 1660 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 1661 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_FR); 1662 } 1663} 1664 1665static void 1666sctp_hs_cwnd_update_after_fr(struct sctp_tcb *stcb, 1667 struct sctp_association *asoc) 1668{ 1669 struct sctp_nets *net; 1670 1671 /* 1672 * CMT fast recovery code. Need to debug. ((sctp_cmt_on_off > 0) && 1673 * (net->fast_retran_loss_recovery == 0))) 1674 */ 1675 TAILQ_FOREACH(net, &asoc->nets, sctp_next) { 1676 if ((asoc->fast_retran_loss_recovery == 0) || 1677 (asoc->sctp_cmt_on_off > 0)) { 1678 /* out of a RFC2582 Fast recovery window? */ 1679 if (net->net_ack > 0) { 1680 /* 1681 * per section 7.2.3, are there any 1682 * destinations that had a fast retransmit 1683 * to them. If so what we need to do is 1684 * adjust ssthresh and cwnd. 1685 */ 1686 struct sctp_tmit_chunk *lchk; 1687 1688 sctp_hs_cwnd_decrease(stcb, net); 1689 1690 lchk = TAILQ_FIRST(&asoc->send_queue); 1691 1692 net->partial_bytes_acked = 0; 1693 /* Turn on fast recovery window */ 1694 asoc->fast_retran_loss_recovery = 1; 1695 if (lchk == NULL) { 1696 /* Mark end of the window */ 1697 asoc->fast_recovery_tsn = asoc->sending_seq - 1; 1698 } else { 1699 asoc->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1; 1700 } 1701 1702 /* 1703 * CMT fast recovery -- per destination 1704 * recovery variable. 1705 */ 1706 net->fast_retran_loss_recovery = 1; 1707 1708 if (lchk == NULL) { 1709 /* Mark end of the window */ 1710 net->fast_recovery_tsn = asoc->sending_seq - 1; 1711 } else { 1712 net->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1; 1713 } 1714 1715 sctp_timer_stop(SCTP_TIMER_TYPE_SEND, 1716 stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_32); 1717 sctp_timer_start(SCTP_TIMER_TYPE_SEND, 1718 stcb->sctp_ep, stcb, net); 1719 } 1720 } else if (net->net_ack > 0) { 1721 /* 1722 * Mark a peg that we WOULD have done a cwnd 1723 * reduction but RFC2582 prevented this action. 1724 */ 1725 SCTP_STAT_INCR(sctps_fastretransinrtt); 1726 } 1727 } 1728} 1729 1730static void 1731sctp_hs_cwnd_update_after_sack(struct sctp_tcb *stcb, 1732 struct sctp_association *asoc, 1733 int accum_moved, int reneged_all SCTP_UNUSED, int will_exit) 1734{ 1735 struct sctp_nets *net; 1736 1737 /******************************/ 1738 /* update cwnd and Early FR */ 1739 /******************************/ 1740 TAILQ_FOREACH(net, &asoc->nets, sctp_next) { 1741 1742#ifdef JANA_CMT_FAST_RECOVERY 1743 /* 1744 * CMT fast recovery code. Need to debug. 1745 */ 1746 if (net->fast_retran_loss_recovery && net->new_pseudo_cumack) { 1747 if (SCTP_TSN_GE(asoc->last_acked_seq, net->fast_recovery_tsn) || 1748 SCTP_TSN_GE(net->pseudo_cumack, net->fast_recovery_tsn)) { 1749 net->will_exit_fast_recovery = 1; 1750 } 1751 } 1752#endif 1753 /* if nothing was acked on this destination skip it */ 1754 if (net->net_ack == 0) { 1755 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) { 1756 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_LOG_FROM_SACK); 1757 } 1758 continue; 1759 } 1760#ifdef JANA_CMT_FAST_RECOVERY 1761 /* 1762 * CMT fast recovery code 1763 */ 1764 /* 1765 * if (sctp_cmt_on_off > 0 && net->fast_retran_loss_recovery 1766 * && net->will_exit_fast_recovery == 0) { @@@ Do something 1767 * } else if (sctp_cmt_on_off == 0 && 1768 * asoc->fast_retran_loss_recovery && will_exit == 0) { 1769 */ 1770#endif 1771 1772 if (asoc->fast_retran_loss_recovery && 1773 (will_exit == 0) && 1774 (asoc->sctp_cmt_on_off == 0)) { 1775 /* 1776 * If we are in loss recovery we skip any cwnd 1777 * update 1778 */ 1779 return; 1780 } 1781 /* 1782 * CMT: CUC algorithm. Update cwnd if pseudo-cumack has 1783 * moved. 1784 */ 1785 if (accum_moved || 1786 ((asoc->sctp_cmt_on_off > 0) && net->new_pseudo_cumack)) { 1787 /* If the cumulative ack moved we can proceed */ 1788 if (net->cwnd <= net->ssthresh) { 1789 /* We are in slow start */ 1790 if (net->flight_size + net->net_ack >= net->cwnd) { 1791 1792 sctp_hs_cwnd_increase(stcb, net); 1793 1794 } else { 1795 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) { 1796 sctp_log_cwnd(stcb, net, net->net_ack, 1797 SCTP_CWND_LOG_NOADV_SS); 1798 } 1799 } 1800 } else { 1801 /* We are in congestion avoidance */ 1802 net->partial_bytes_acked += net->net_ack; 1803 if ((net->flight_size + net->net_ack >= net->cwnd) && 1804 (net->partial_bytes_acked >= net->cwnd)) { 1805 net->partial_bytes_acked -= net->cwnd; 1806 net->cwnd += net->mtu; 1807 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 1808 sctp_log_cwnd(stcb, net, net->mtu, 1809 SCTP_CWND_LOG_FROM_CA); 1810 } 1811 } else { 1812 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) { 1813 sctp_log_cwnd(stcb, net, net->net_ack, 1814 SCTP_CWND_LOG_NOADV_CA); 1815 } 1816 } 1817 } 1818 } else { 1819 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) { 1820 sctp_log_cwnd(stcb, net, net->mtu, 1821 SCTP_CWND_LOG_NO_CUMACK); 1822 } 1823 } 1824 } 1825} 1826 1827 1828/* 1829 * H-TCP congestion control. The algorithm is detailed in: 1830 * R.N.Shorten, D.J.Leith: 1831 * "H-TCP: TCP for high-speed and long-distance networks" 1832 * Proc. PFLDnet, Argonne, 2004. 1833 * http://www.hamilton.ie/net/htcp3.pdf 1834 */ 1835 1836 1837static int use_rtt_scaling = 1; 1838static int use_bandwidth_switch = 1; 1839 1840static inline int 1841between(uint32_t seq1, uint32_t seq2, uint32_t seq3) 1842{ 1843 return (seq3 - seq2 >= seq1 - seq2); 1844} 1845 1846static inline uint32_t 1847htcp_cong_time(struct htcp *ca) 1848{ 1849 return (sctp_get_tick_count() - ca->last_cong); 1850} 1851 1852static inline uint32_t 1853htcp_ccount(struct htcp *ca) 1854{ 1855 return (htcp_cong_time(ca) / ca->minRTT); 1856} 1857 1858static inline void 1859htcp_reset(struct htcp *ca) 1860{ 1861 ca->undo_last_cong = ca->last_cong; 1862 ca->undo_maxRTT = ca->maxRTT; 1863 ca->undo_old_maxB = ca->old_maxB; 1864 ca->last_cong = sctp_get_tick_count(); 1865} 1866 1867#ifdef SCTP_NOT_USED 1868 1869static uint32_t 1870htcp_cwnd_undo(struct sctp_tcb *stcb, struct sctp_nets *net) 1871{ 1872 net->cc_mod.htcp_ca.last_cong = net->cc_mod.htcp_ca.undo_last_cong; 1873 net->cc_mod.htcp_ca.maxRTT = net->cc_mod.htcp_ca.undo_maxRTT; 1874 net->cc_mod.htcp_ca.old_maxB = net->cc_mod.htcp_ca.undo_old_maxB; 1875 return (max(net->cwnd, ((net->ssthresh / net->mtu << 7) / net->cc_mod.htcp_ca.beta) * net->mtu)); 1876} 1877 1878#endif 1879 1880static inline void 1881measure_rtt(struct sctp_nets *net) 1882{ 1883 uint32_t srtt = net->lastsa >> SCTP_RTT_SHIFT; 1884 1885 /* keep track of minimum RTT seen so far, minRTT is zero at first */ 1886 if (net->cc_mod.htcp_ca.minRTT > srtt || !net->cc_mod.htcp_ca.minRTT) 1887 net->cc_mod.htcp_ca.minRTT = srtt; 1888 1889 /* max RTT */ 1890 if (net->fast_retran_ip == 0 && net->ssthresh < 0xFFFF && htcp_ccount(&net->cc_mod.htcp_ca) > 3) { 1891 if (net->cc_mod.htcp_ca.maxRTT < net->cc_mod.htcp_ca.minRTT) 1892 net->cc_mod.htcp_ca.maxRTT = net->cc_mod.htcp_ca.minRTT; 1893 if (net->cc_mod.htcp_ca.maxRTT < srtt && srtt <= net->cc_mod.htcp_ca.maxRTT + MSEC_TO_TICKS(20)) 1894 net->cc_mod.htcp_ca.maxRTT = srtt; 1895 } 1896} 1897 1898static void 1899measure_achieved_throughput(struct sctp_nets *net) 1900{ 1901 uint32_t now = sctp_get_tick_count(); 1902 1903 if (net->fast_retran_ip == 0) 1904 net->cc_mod.htcp_ca.bytes_acked = net->net_ack; 1905 1906 if (!use_bandwidth_switch) 1907 return; 1908 1909 /* achieved throughput calculations */ 1910 /* JRS - not 100% sure of this statement */ 1911 if (net->fast_retran_ip == 1) { 1912 net->cc_mod.htcp_ca.bytecount = 0; 1913 net->cc_mod.htcp_ca.lasttime = now; 1914 return; 1915 } 1916 net->cc_mod.htcp_ca.bytecount += net->net_ack; 1917 if ((net->cc_mod.htcp_ca.bytecount >= net->cwnd - (((net->cc_mod.htcp_ca.alpha >> 7) ? (net->cc_mod.htcp_ca.alpha >> 7) : 1) * net->mtu)) && 1918 (now - net->cc_mod.htcp_ca.lasttime >= net->cc_mod.htcp_ca.minRTT) && 1919 (net->cc_mod.htcp_ca.minRTT > 0)) { 1920 uint32_t cur_Bi = net->cc_mod.htcp_ca.bytecount / net->mtu * hz / (now - net->cc_mod.htcp_ca.lasttime); 1921 1922 if (htcp_ccount(&net->cc_mod.htcp_ca) <= 3) { 1923 /* just after backoff */ 1924 net->cc_mod.htcp_ca.minB = net->cc_mod.htcp_ca.maxB = net->cc_mod.htcp_ca.Bi = cur_Bi; 1925 } else { 1926 net->cc_mod.htcp_ca.Bi = (3 * net->cc_mod.htcp_ca.Bi + cur_Bi) / 4; 1927 if (net->cc_mod.htcp_ca.Bi > net->cc_mod.htcp_ca.maxB) 1928 net->cc_mod.htcp_ca.maxB = net->cc_mod.htcp_ca.Bi; 1929 if (net->cc_mod.htcp_ca.minB > net->cc_mod.htcp_ca.maxB) 1930 net->cc_mod.htcp_ca.minB = net->cc_mod.htcp_ca.maxB; 1931 } 1932 net->cc_mod.htcp_ca.bytecount = 0; 1933 net->cc_mod.htcp_ca.lasttime = now; 1934 } 1935} 1936 1937static inline void 1938htcp_beta_update(struct htcp *ca, uint32_t minRTT, uint32_t maxRTT) 1939{ 1940 if (use_bandwidth_switch) { 1941 uint32_t maxB = ca->maxB; 1942 uint32_t old_maxB = ca->old_maxB; 1943 1944 ca->old_maxB = ca->maxB; 1945 1946 if (!between(5 * maxB, 4 * old_maxB, 6 * old_maxB)) { 1947 ca->beta = BETA_MIN; 1948 ca->modeswitch = 0; 1949 return; 1950 } 1951 } 1952 if (ca->modeswitch && minRTT > (uint32_t) MSEC_TO_TICKS(10) && maxRTT) { 1953 ca->beta = (minRTT << 7) / maxRTT; 1954 if (ca->beta < BETA_MIN) 1955 ca->beta = BETA_MIN; 1956 else if (ca->beta > BETA_MAX) 1957 ca->beta = BETA_MAX; 1958 } else { 1959 ca->beta = BETA_MIN; 1960 ca->modeswitch = 1; 1961 } 1962} 1963 1964static inline void 1965htcp_alpha_update(struct htcp *ca) 1966{ 1967 uint32_t minRTT = ca->minRTT; 1968 uint32_t factor = 1; 1969 uint32_t diff = htcp_cong_time(ca); 1970 1971 if (diff > (uint32_t) hz) { 1972 diff -= hz; 1973 factor = 1 + (10 * diff + ((diff / 2) * (diff / 2) / hz)) / hz; 1974 } 1975 if (use_rtt_scaling && minRTT) { 1976 uint32_t scale = (hz << 3) / (10 * minRTT); 1977 1978 scale = min(max(scale, 1U << 2), 10U << 3); /* clamping ratio to 1979 * interval [0.5,10]<<3 */ 1980 factor = (factor << 3) / scale; 1981 if (!factor) 1982 factor = 1; 1983 } 1984 ca->alpha = 2 * factor * ((1 << 7) - ca->beta); 1985 if (!ca->alpha) 1986 ca->alpha = ALPHA_BASE; 1987} 1988 1989/* After we have the rtt data to calculate beta, we'd still prefer to wait one 1990 * rtt before we adjust our beta to ensure we are working from a consistent 1991 * data. 1992 * 1993 * This function should be called when we hit a congestion event since only at 1994 * that point do we really have a real sense of maxRTT (the queues en route 1995 * were getting just too full now). 1996 */ 1997static void 1998htcp_param_update(struct sctp_nets *net) 1999{ 2000 uint32_t minRTT = net->cc_mod.htcp_ca.minRTT; 2001 uint32_t maxRTT = net->cc_mod.htcp_ca.maxRTT; 2002 2003 htcp_beta_update(&net->cc_mod.htcp_ca, minRTT, maxRTT); 2004 htcp_alpha_update(&net->cc_mod.htcp_ca); 2005 2006 /* 2007 * add slowly fading memory for maxRTT to accommodate routing 2008 * changes etc 2009 */ 2010 if (minRTT > 0 && maxRTT > minRTT) 2011 net->cc_mod.htcp_ca.maxRTT = minRTT + ((maxRTT - minRTT) * 95) / 100; 2012} 2013 2014static uint32_t 2015htcp_recalc_ssthresh(struct sctp_nets *net) 2016{ 2017 htcp_param_update(net); 2018 return (max(((net->cwnd / net->mtu * net->cc_mod.htcp_ca.beta) >> 7) * net->mtu, 2U * net->mtu)); 2019} 2020 2021static void 2022htcp_cong_avoid(struct sctp_tcb *stcb, struct sctp_nets *net) 2023{ 2024 /*- 2025 * How to handle these functions? 2026 * if (!tcp_is_cwnd_limited(sk, in_flight)) RRS - good question. 2027 * return; 2028 */ 2029 if (net->cwnd <= net->ssthresh) { 2030 /* We are in slow start */ 2031 if (net->flight_size + net->net_ack >= net->cwnd) { 2032 if (net->net_ack > (net->mtu * SCTP_BASE_SYSCTL(sctp_L2_abc_variable))) { 2033 net->cwnd += (net->mtu * SCTP_BASE_SYSCTL(sctp_L2_abc_variable)); 2034 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 2035 sctp_log_cwnd(stcb, net, net->mtu, 2036 SCTP_CWND_LOG_FROM_SS); 2037 } 2038 } else { 2039 net->cwnd += net->net_ack; 2040 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 2041 sctp_log_cwnd(stcb, net, net->net_ack, 2042 SCTP_CWND_LOG_FROM_SS); 2043 } 2044 } 2045 } else { 2046 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) { 2047 sctp_log_cwnd(stcb, net, net->net_ack, 2048 SCTP_CWND_LOG_NOADV_SS); 2049 } 2050 } 2051 } else { 2052 measure_rtt(net); 2053 2054 /* 2055 * In dangerous area, increase slowly. In theory this is 2056 * net->cwnd += alpha / net->cwnd 2057 */ 2058 /* What is snd_cwnd_cnt?? */ 2059 if (((net->partial_bytes_acked / net->mtu * net->cc_mod.htcp_ca.alpha) >> 7) * net->mtu >= net->cwnd) { 2060 /*- 2061 * Does SCTP have a cwnd clamp? 2062 * if (net->snd_cwnd < net->snd_cwnd_clamp) - Nope (RRS). 2063 */ 2064 net->cwnd += net->mtu; 2065 net->partial_bytes_acked = 0; 2066 htcp_alpha_update(&net->cc_mod.htcp_ca); 2067 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 2068 sctp_log_cwnd(stcb, net, net->mtu, 2069 SCTP_CWND_LOG_FROM_CA); 2070 } 2071 } else { 2072 net->partial_bytes_acked += net->net_ack; 2073 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) { 2074 sctp_log_cwnd(stcb, net, net->net_ack, 2075 SCTP_CWND_LOG_NOADV_CA); 2076 } 2077 } 2078 2079 net->cc_mod.htcp_ca.bytes_acked = net->mtu; 2080 } 2081} 2082 2083#ifdef SCTP_NOT_USED 2084/* Lower bound on congestion window. */ 2085static uint32_t 2086htcp_min_cwnd(struct sctp_tcb *stcb, struct sctp_nets *net) 2087{ 2088 return (net->ssthresh); 2089} 2090 2091#endif 2092 2093static void 2094htcp_init(struct sctp_nets *net) 2095{ 2096 memset(&net->cc_mod.htcp_ca, 0, sizeof(struct htcp)); 2097 net->cc_mod.htcp_ca.alpha = ALPHA_BASE; 2098 net->cc_mod.htcp_ca.beta = BETA_MIN; 2099 net->cc_mod.htcp_ca.bytes_acked = net->mtu; 2100 net->cc_mod.htcp_ca.last_cong = sctp_get_tick_count(); 2101} 2102 2103static void 2104sctp_htcp_set_initial_cc_param(struct sctp_tcb *stcb, struct sctp_nets *net) 2105{ 2106 /* 2107 * We take the max of the burst limit times a MTU or the 2108 * INITIAL_CWND. We then limit this to 4 MTU's of sending. 2109 */ 2110 net->cwnd = min((net->mtu * 4), max((2 * net->mtu), SCTP_INITIAL_CWND)); 2111 net->ssthresh = stcb->asoc.peers_rwnd; 2112 htcp_init(net); 2113 2114 if (SCTP_BASE_SYSCTL(sctp_logging_level) & (SCTP_CWND_MONITOR_ENABLE | SCTP_CWND_LOGGING_ENABLE)) { 2115 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_INITIALIZATION); 2116 } 2117} 2118 2119static void 2120sctp_htcp_cwnd_update_after_sack(struct sctp_tcb *stcb, 2121 struct sctp_association *asoc, 2122 int accum_moved, int reneged_all SCTP_UNUSED, int will_exit) 2123{ 2124 struct sctp_nets *net; 2125 2126 /******************************/ 2127 /* update cwnd and Early FR */ 2128 /******************************/ 2129 TAILQ_FOREACH(net, &asoc->nets, sctp_next) { 2130 2131#ifdef JANA_CMT_FAST_RECOVERY 2132 /* 2133 * CMT fast recovery code. Need to debug. 2134 */ 2135 if (net->fast_retran_loss_recovery && net->new_pseudo_cumack) { 2136 if (SCTP_TSN_GE(asoc->last_acked_seq, net->fast_recovery_tsn) || 2137 SCTP_TSN_GE(net->pseudo_cumack, net->fast_recovery_tsn)) { 2138 net->will_exit_fast_recovery = 1; 2139 } 2140 } 2141#endif 2142 /* if nothing was acked on this destination skip it */ 2143 if (net->net_ack == 0) { 2144 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) { 2145 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_LOG_FROM_SACK); 2146 } 2147 continue; 2148 } 2149#ifdef JANA_CMT_FAST_RECOVERY 2150 /* 2151 * CMT fast recovery code 2152 */ 2153 /* 2154 * if (sctp_cmt_on_off > 0 && net->fast_retran_loss_recovery 2155 * && net->will_exit_fast_recovery == 0) { @@@ Do something 2156 * } else if (sctp_cmt_on_off == 0 && 2157 * asoc->fast_retran_loss_recovery && will_exit == 0) { 2158 */ 2159#endif 2160 2161 if (asoc->fast_retran_loss_recovery && 2162 will_exit == 0 && 2163 (asoc->sctp_cmt_on_off == 0)) { 2164 /* 2165 * If we are in loss recovery we skip any cwnd 2166 * update 2167 */ 2168 return; 2169 } 2170 /* 2171 * CMT: CUC algorithm. Update cwnd if pseudo-cumack has 2172 * moved. 2173 */ 2174 if (accum_moved || 2175 ((asoc->sctp_cmt_on_off > 0) && net->new_pseudo_cumack)) { 2176 htcp_cong_avoid(stcb, net); 2177 measure_achieved_throughput(net); 2178 } else { 2179 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) { 2180 sctp_log_cwnd(stcb, net, net->mtu, 2181 SCTP_CWND_LOG_NO_CUMACK); 2182 } 2183 } 2184 } 2185} 2186 2187static void 2188sctp_htcp_cwnd_update_after_fr(struct sctp_tcb *stcb, 2189 struct sctp_association *asoc) 2190{ 2191 struct sctp_nets *net; 2192 2193 /* 2194 * CMT fast recovery code. Need to debug. ((sctp_cmt_on_off > 0) && 2195 * (net->fast_retran_loss_recovery == 0))) 2196 */ 2197 TAILQ_FOREACH(net, &asoc->nets, sctp_next) { 2198 if ((asoc->fast_retran_loss_recovery == 0) || 2199 (asoc->sctp_cmt_on_off > 0)) { 2200 /* out of a RFC2582 Fast recovery window? */ 2201 if (net->net_ack > 0) { 2202 /* 2203 * per section 7.2.3, are there any 2204 * destinations that had a fast retransmit 2205 * to them. If so what we need to do is 2206 * adjust ssthresh and cwnd. 2207 */ 2208 struct sctp_tmit_chunk *lchk; 2209 int old_cwnd = net->cwnd; 2210 2211 /* JRS - reset as if state were changed */ 2212 htcp_reset(&net->cc_mod.htcp_ca); 2213 net->ssthresh = htcp_recalc_ssthresh(net); 2214 net->cwnd = net->ssthresh; 2215 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 2216 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), 2217 SCTP_CWND_LOG_FROM_FR); 2218 } 2219 lchk = TAILQ_FIRST(&asoc->send_queue); 2220 2221 net->partial_bytes_acked = 0; 2222 /* Turn on fast recovery window */ 2223 asoc->fast_retran_loss_recovery = 1; 2224 if (lchk == NULL) { 2225 /* Mark end of the window */ 2226 asoc->fast_recovery_tsn = asoc->sending_seq - 1; 2227 } else { 2228 asoc->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1; 2229 } 2230 2231 /* 2232 * CMT fast recovery -- per destination 2233 * recovery variable. 2234 */ 2235 net->fast_retran_loss_recovery = 1; 2236 2237 if (lchk == NULL) { 2238 /* Mark end of the window */ 2239 net->fast_recovery_tsn = asoc->sending_seq - 1; 2240 } else { 2241 net->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1; 2242 } 2243 2244 sctp_timer_stop(SCTP_TIMER_TYPE_SEND, 2245 stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_32); 2246 sctp_timer_start(SCTP_TIMER_TYPE_SEND, 2247 stcb->sctp_ep, stcb, net); 2248 } 2249 } else if (net->net_ack > 0) { 2250 /* 2251 * Mark a peg that we WOULD have done a cwnd 2252 * reduction but RFC2582 prevented this action. 2253 */ 2254 SCTP_STAT_INCR(sctps_fastretransinrtt); 2255 } 2256 } 2257} 2258 2259static void 2260sctp_htcp_cwnd_update_after_timeout(struct sctp_tcb *stcb, 2261 struct sctp_nets *net) 2262{ 2263 int old_cwnd = net->cwnd; 2264 2265 /* JRS - reset as if the state were being changed to timeout */ 2266 htcp_reset(&net->cc_mod.htcp_ca); 2267 net->ssthresh = htcp_recalc_ssthresh(net); 2268 net->cwnd = net->mtu; 2269 net->partial_bytes_acked = 0; 2270 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 2271 sctp_log_cwnd(stcb, net, net->cwnd - old_cwnd, SCTP_CWND_LOG_FROM_RTX); 2272 } 2273} 2274 2275static void 2276sctp_htcp_cwnd_update_after_ecn_echo(struct sctp_tcb *stcb, 2277 struct sctp_nets *net, int in_window, int num_pkt_lost SCTP_UNUSED) 2278{ 2279 int old_cwnd; 2280 2281 old_cwnd = net->cwnd; 2282 2283 /* JRS - reset hctp as if state changed */ 2284 if (in_window == 0) { 2285 htcp_reset(&net->cc_mod.htcp_ca); 2286 SCTP_STAT_INCR(sctps_ecnereducedcwnd); 2287 net->ssthresh = htcp_recalc_ssthresh(net); 2288 if (net->ssthresh < net->mtu) { 2289 net->ssthresh = net->mtu; 2290 /* here back off the timer as well, to slow us down */ 2291 net->RTO <<= 1; 2292 } 2293 net->cwnd = net->ssthresh; 2294 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 2295 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT); 2296 } 2297 } 2298} 2299 2300struct sctp_cc_functions sctp_cc_functions[] = { 2301 { 2302 .sctp_set_initial_cc_param = sctp_set_initial_cc_param, 2303 .sctp_cwnd_update_after_sack = sctp_cwnd_update_after_sack, 2304 .sctp_cwnd_update_exit_pf = sctp_cwnd_update_exit_pf_common, 2305 .sctp_cwnd_update_after_fr = sctp_cwnd_update_after_fr, 2306 .sctp_cwnd_update_after_timeout = sctp_cwnd_update_after_timeout, 2307 .sctp_cwnd_update_after_ecn_echo = sctp_cwnd_update_after_ecn_echo, 2308 .sctp_cwnd_update_after_packet_dropped = sctp_cwnd_update_after_packet_dropped, 2309 .sctp_cwnd_update_after_output = sctp_cwnd_update_after_output, 2310 }, 2311 { 2312 .sctp_set_initial_cc_param = sctp_set_initial_cc_param, 2313 .sctp_cwnd_update_after_sack = sctp_hs_cwnd_update_after_sack, 2314 .sctp_cwnd_update_exit_pf = sctp_cwnd_update_exit_pf_common, 2315 .sctp_cwnd_update_after_fr = sctp_hs_cwnd_update_after_fr, 2316 .sctp_cwnd_update_after_timeout = sctp_cwnd_update_after_timeout, 2317 .sctp_cwnd_update_after_ecn_echo = sctp_cwnd_update_after_ecn_echo, 2318 .sctp_cwnd_update_after_packet_dropped = sctp_cwnd_update_after_packet_dropped, 2319 .sctp_cwnd_update_after_output = sctp_cwnd_update_after_output, 2320 }, 2321 { 2322 .sctp_set_initial_cc_param = sctp_htcp_set_initial_cc_param, 2323 .sctp_cwnd_update_after_sack = sctp_htcp_cwnd_update_after_sack, 2324 .sctp_cwnd_update_exit_pf = sctp_cwnd_update_exit_pf_common, 2325 .sctp_cwnd_update_after_fr = sctp_htcp_cwnd_update_after_fr, 2326 .sctp_cwnd_update_after_timeout = sctp_htcp_cwnd_update_after_timeout, 2327 .sctp_cwnd_update_after_ecn_echo = sctp_htcp_cwnd_update_after_ecn_echo, 2328 .sctp_cwnd_update_after_packet_dropped = sctp_cwnd_update_after_packet_dropped, 2329 .sctp_cwnd_update_after_output = sctp_cwnd_update_after_output, 2330 }, 2331 { 2332 .sctp_set_initial_cc_param = sctp_set_rtcc_initial_cc_param, 2333 .sctp_cwnd_update_after_sack = sctp_cwnd_update_rtcc_after_sack, 2334 .sctp_cwnd_update_exit_pf = sctp_cwnd_update_exit_pf_common, 2335 .sctp_cwnd_update_after_fr = sctp_cwnd_update_after_fr, 2336 .sctp_cwnd_update_after_timeout = sctp_cwnd_update_after_timeout, 2337 .sctp_cwnd_update_after_ecn_echo = sctp_cwnd_update_rtcc_after_ecn_echo, 2338 .sctp_cwnd_update_after_packet_dropped = sctp_cwnd_update_after_packet_dropped, 2339 .sctp_cwnd_update_after_output = sctp_cwnd_update_after_output, 2340 .sctp_cwnd_update_packet_transmitted = sctp_cwnd_update_rtcc_packet_transmitted, 2341 .sctp_cwnd_update_tsn_acknowledged = sctp_cwnd_update_rtcc_tsn_acknowledged, 2342 .sctp_cwnd_new_transmission_begins = sctp_cwnd_new_rtcc_transmission_begins, 2343 .sctp_cwnd_prepare_net_for_sack = sctp_cwnd_prepare_rtcc_net_for_sack, 2344 .sctp_cwnd_socket_option = sctp_cwnd_rtcc_socket_option, 2345 .sctp_rtt_calculated = sctp_rtt_rtcc_calculated 2346 } 2347}; 2348