sample.c revision 219216
1/*- 2 * Copyright (c) 2005 John Bicket 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer, 10 * without modification. 11 * 2. Redistributions in binary form must reproduce at minimum a disclaimer 12 * similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any 13 * redistribution must be conditioned upon including a substantially 14 * similar Disclaimer requirement for further binary redistribution. 15 * 3. Neither the names of the above-listed copyright holders nor the names 16 * of any contributors may be used to endorse or promote products derived 17 * from this software without specific prior written permission. 18 * 19 * Alternatively, this software may be distributed under the terms of the 20 * GNU General Public License ("GPL") version 2 as published by the Free 21 * Software Foundation. 22 * 23 * NO WARRANTY 24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 25 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 26 * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY 27 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 28 * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, 29 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER 32 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 34 * THE POSSIBILITY OF SUCH DAMAGES. 35 * 36 */ 37 38#include <sys/cdefs.h> 39__FBSDID("$FreeBSD: head/sys/dev/ath/ath_rate/sample/sample.c 219216 2011-03-03 08:09:49Z adrian $"); 40 41/* 42 * John Bicket's SampleRate control algorithm. 43 */ 44#include "opt_inet.h" 45#include "opt_wlan.h" 46 47#include <sys/param.h> 48#include <sys/systm.h> 49#include <sys/sysctl.h> 50#include <sys/kernel.h> 51#include <sys/lock.h> 52#include <sys/mutex.h> 53#include <sys/errno.h> 54 55#include <machine/bus.h> 56#include <machine/resource.h> 57#include <sys/bus.h> 58 59#include <sys/socket.h> 60 61#include <net/if.h> 62#include <net/if_media.h> 63#include <net/if_arp.h> 64#include <net/ethernet.h> /* XXX for ether_sprintf */ 65 66#include <net80211/ieee80211_var.h> 67 68#include <net/bpf.h> 69 70#ifdef INET 71#include <netinet/in.h> 72#include <netinet/if_ether.h> 73#endif 74 75#include <dev/ath/if_athvar.h> 76#include <dev/ath/ath_rate/sample/sample.h> 77#include <dev/ath/ath_hal/ah_desc.h> 78#include <dev/ath/ath_rate/sample/tx_schedules.h> 79 80/* 81 * This file is an implementation of the SampleRate algorithm 82 * in "Bit-rate Selection in Wireless Networks" 83 * (http://www.pdos.lcs.mit.edu/papers/jbicket-ms.ps) 84 * 85 * SampleRate chooses the bit-rate it predicts will provide the most 86 * throughput based on estimates of the expected per-packet 87 * transmission time for each bit-rate. SampleRate periodically sends 88 * packets at bit-rates other than the current one to estimate when 89 * another bit-rate will provide better performance. SampleRate 90 * switches to another bit-rate when its estimated per-packet 91 * transmission time becomes smaller than the current bit-rate's. 92 * SampleRate reduces the number of bit-rates it must sample by 93 * eliminating those that could not perform better than the one 94 * currently being used. SampleRate also stops probing at a bit-rate 95 * if it experiences several successive losses. 96 * 97 * The difference between the algorithm in the thesis and the one in this 98 * file is that the one in this file uses a ewma instead of a window. 99 * 100 * Also, this implementation tracks the average transmission time for 101 * a few different packet sizes independently for each link. 102 */ 103 104static void ath_rate_ctl_reset(struct ath_softc *, struct ieee80211_node *); 105 106static const int packet_size_bins[NUM_PACKET_SIZE_BINS] = { 250, 1600 }; 107 108static __inline int 109size_to_bin(int size) 110{ 111#if NUM_PACKET_SIZE_BINS > 1 112 if (size <= packet_size_bins[0]) 113 return 0; 114#endif 115#if NUM_PACKET_SIZE_BINS > 2 116 if (size <= packet_size_bins[1]) 117 return 1; 118#endif 119#if NUM_PACKET_SIZE_BINS > 3 120 if (size <= packet_size_bins[2]) 121 return 2; 122#endif 123#if NUM_PACKET_SIZE_BINS > 4 124#error "add support for more packet sizes" 125#endif 126 return NUM_PACKET_SIZE_BINS-1; 127} 128 129static __inline int 130bin_to_size(int index) 131{ 132 return packet_size_bins[index]; 133} 134 135void 136ath_rate_node_init(struct ath_softc *sc, struct ath_node *an) 137{ 138 /* NB: assumed to be zero'd by caller */ 139} 140 141void 142ath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an) 143{ 144} 145 146static int 147dot11rate(const HAL_RATE_TABLE *rt, int rix) 148{ 149 return rt->info[rix].phy == IEEE80211_T_HT ? 150 rt->info[rix].dot11Rate : (rt->info[rix].dot11Rate & IEEE80211_RATE_VAL) / 2; 151} 152 153static const char * 154dot11rate_label(const HAL_RATE_TABLE *rt, int rix) 155{ 156 return rt->info[rix].phy == IEEE80211_T_HT ? "MCS" : "Mb "; 157} 158 159/* 160 * Return the rix with the lowest average_tx_time, 161 * or -1 if all the average_tx_times are 0. 162 */ 163static __inline int 164pick_best_rate(struct sample_node *sn, const HAL_RATE_TABLE *rt, 165 int size_bin, int require_acked_before) 166{ 167 int best_rate_rix, best_rate_tt; 168 uint32_t mask; 169 int rix, tt; 170 171 best_rate_rix = 0; 172 best_rate_tt = 0; 173 for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) { 174 if ((mask & 1) == 0) /* not a supported rate */ 175 continue; 176 177 tt = sn->stats[size_bin][rix].average_tx_time; 178 if (tt <= 0 || 179 (require_acked_before && 180 !sn->stats[size_bin][rix].packets_acked)) 181 continue; 182 183 /* don't use a bit-rate that has been failing */ 184 if (sn->stats[size_bin][rix].successive_failures > 3) 185 continue; 186 187 if (best_rate_tt == 0 || tt < best_rate_tt) { 188 best_rate_tt = tt; 189 best_rate_rix = rix; 190 } 191 } 192 return (best_rate_tt ? best_rate_rix : -1); 193} 194 195/* 196 * Pick a good "random" bit-rate to sample other than the current one. 197 */ 198static __inline int 199pick_sample_rate(struct sample_softc *ssc , struct sample_node *sn, 200 const HAL_RATE_TABLE *rt, int size_bin) 201{ 202#define DOT11RATE(ix) (rt->info[ix].dot11Rate & IEEE80211_RATE_VAL) 203#define MCS(ix) (rt->info[ix].dot11Rate | IEEE80211_RATE_MCS) 204 int current_rix, rix; 205 unsigned current_tt; 206 uint32_t mask; 207 208 current_rix = sn->current_rix[size_bin]; 209 if (current_rix < 0) { 210 /* no successes yet, send at the lowest bit-rate */ 211 return 0; 212 } 213 214 current_tt = sn->stats[size_bin][current_rix].average_tx_time; 215 216 rix = sn->last_sample_rix[size_bin]+1; /* next sample rate */ 217 mask = sn->ratemask &~ (1<<current_rix);/* don't sample current rate */ 218 while (mask != 0) { 219 if ((mask & (1<<rix)) == 0) { /* not a supported rate */ 220 nextrate: 221 if (++rix >= rt->rateCount) 222 rix = 0; 223 continue; 224 } 225 226 /* this bit-rate is always worse than the current one */ 227 if (sn->stats[size_bin][rix].perfect_tx_time > current_tt) { 228 mask &= ~(1<<rix); 229 goto nextrate; 230 } 231 232 /* rarely sample bit-rates that fail a lot */ 233 if (sn->stats[size_bin][rix].successive_failures > ssc->max_successive_failures && 234 ticks - sn->stats[size_bin][rix].last_tx < ssc->stale_failure_timeout) { 235 mask &= ~(1<<rix); 236 goto nextrate; 237 } 238 239 /* don't sample more than 2 rates higher for rates > 11M */ 240 if (DOT11RATE(rix) > 2*11 && rix > current_rix + 2) { 241 mask &= ~(1<<rix); 242 goto nextrate; 243 } 244 245 sn->last_sample_rix[size_bin] = rix; 246 return rix; 247 } 248 return current_rix; 249#undef DOT11RATE 250#undef MCS 251} 252 253void 254ath_rate_findrate(struct ath_softc *sc, struct ath_node *an, 255 int shortPreamble, size_t frameLen, 256 u_int8_t *rix0, int *try0, u_int8_t *txrate) 257{ 258#define DOT11RATE(ix) (rt->info[ix].dot11Rate & IEEE80211_RATE_VAL) 259#define MCS(ix) (rt->info[ix].dot11Rate | IEEE80211_RATE_MCS) 260#define RATE(ix) (DOT11RATE(ix) / 2) 261 struct sample_node *sn = ATH_NODE_SAMPLE(an); 262 struct sample_softc *ssc = ATH_SOFTC_SAMPLE(sc); 263 struct ifnet *ifp = sc->sc_ifp; 264 struct ieee80211com *ic = ifp->if_l2com; 265 const HAL_RATE_TABLE *rt = sc->sc_currates; 266 const int size_bin = size_to_bin(frameLen); 267 int rix, mrr, best_rix, change_rates; 268 unsigned average_tx_time; 269 270 if (sn->static_rix != -1) { 271 rix = sn->static_rix; 272 *try0 = ATH_TXMAXTRY; 273 goto done; 274 } 275 276 mrr = sc->sc_mrretry && !(ic->ic_flags & IEEE80211_F_USEPROT); 277 278 best_rix = pick_best_rate(sn, rt, size_bin, !mrr); 279 if (best_rix >= 0) { 280 average_tx_time = sn->stats[size_bin][best_rix].average_tx_time; 281 } else { 282 average_tx_time = 0; 283 } 284 /* 285 * Limit the time measuring the performance of other tx 286 * rates to sample_rate% of the total transmission time. 287 */ 288 if (sn->sample_tt[size_bin] < average_tx_time * (sn->packets_since_sample[size_bin]*ssc->sample_rate/100)) { 289 rix = pick_sample_rate(ssc, sn, rt, size_bin); 290 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 291 &an->an_node, "size %u sample rate %d current rate %d", 292 bin_to_size(size_bin), RATE(rix), 293 RATE(sn->current_rix[size_bin])); 294 if (rix != sn->current_rix[size_bin]) { 295 sn->current_sample_rix[size_bin] = rix; 296 } else { 297 sn->current_sample_rix[size_bin] = -1; 298 } 299 sn->packets_since_sample[size_bin] = 0; 300 } else { 301 change_rates = 0; 302 if (!sn->packets_sent[size_bin] || best_rix == -1) { 303 /* no packet has been sent successfully yet */ 304 for (rix = rt->rateCount-1; rix > 0; rix--) { 305 if ((sn->ratemask & (1<<rix)) == 0) 306 continue; 307 /* 308 * Pick the highest rate <= 36 Mbps 309 * that hasn't failed. 310 */ 311 if (DOT11RATE(rix) <= 72 && 312 sn->stats[size_bin][rix].successive_failures == 0) { 313 break; 314 } 315 } 316 change_rates = 1; 317 best_rix = rix; 318 } else if (sn->packets_sent[size_bin] < 20) { 319 /* let the bit-rate switch quickly during the first few packets */ 320 change_rates = 1; 321 } else if (ticks - ssc->min_switch > sn->ticks_since_switch[size_bin]) { 322 /* min_switch seconds have gone by */ 323 change_rates = 1; 324 } else if (2*average_tx_time < sn->stats[size_bin][sn->current_rix[size_bin]].average_tx_time) { 325 /* the current bit-rate is twice as slow as the best one */ 326 change_rates = 1; 327 } 328 329 sn->packets_since_sample[size_bin]++; 330 331 if (change_rates) { 332 if (best_rix != sn->current_rix[size_bin]) { 333 IEEE80211_NOTE(an->an_node.ni_vap, 334 IEEE80211_MSG_RATECTL, 335 &an->an_node, 336"%s: size %d switch rate %d (%d/%d) -> %d (%d/%d) after %d packets mrr %d", 337 __func__, 338 bin_to_size(size_bin), 339 RATE(sn->current_rix[size_bin]), 340 sn->stats[size_bin][sn->current_rix[size_bin]].average_tx_time, 341 sn->stats[size_bin][sn->current_rix[size_bin]].perfect_tx_time, 342 RATE(best_rix), 343 sn->stats[size_bin][best_rix].average_tx_time, 344 sn->stats[size_bin][best_rix].perfect_tx_time, 345 sn->packets_since_switch[size_bin], 346 mrr); 347 } 348 sn->packets_since_switch[size_bin] = 0; 349 sn->current_rix[size_bin] = best_rix; 350 sn->ticks_since_switch[size_bin] = ticks; 351 /* 352 * Set the visible txrate for this node. 353 */ 354 an->an_node.ni_txrate = (rt->info[best_rix].phy == IEEE80211_T_HT) ? MCS(best_rix) : DOT11RATE(best_rix); 355 } 356 rix = sn->current_rix[size_bin]; 357 sn->packets_since_switch[size_bin]++; 358 } 359 *try0 = mrr ? sn->sched[rix].t0 : ATH_TXMAXTRY; 360done: 361 KASSERT(rix >= 0 && rix < rt->rateCount, ("rix is %d", rix)); 362 363 *rix0 = rix; 364 *txrate = rt->info[rix].rateCode 365 | (shortPreamble ? rt->info[rix].shortPreamble : 0); 366 sn->packets_sent[size_bin]++; 367#undef DOT11RATE 368#undef MCS 369#undef RATE 370} 371 372/* 373 * Get the TX rates. Don't fiddle with short preamble flags for them; 374 * the caller can do that. 375 */ 376void 377ath_rate_getxtxrates(struct ath_softc *sc, struct ath_node *an, 378 uint8_t rix0, uint8_t *rix, uint8_t *try) 379{ 380 struct sample_node *sn = ATH_NODE_SAMPLE(an); 381 const struct txschedule *sched = &sn->sched[rix0]; 382 383 KASSERT(rix0 == sched->r0, ("rix0 (%x) != sched->r0 (%x)!\n", rix0, sched->r0)); 384 385/* rix[0] = sched->r0; */ 386 rix[1] = sched->r1; 387 rix[2] = sched->r2; 388 rix[3] = sched->r3; 389 390 try[0] = sched->t0; 391 try[1] = sched->t1; 392 try[2] = sched->t2; 393 try[3] = sched->t3; 394} 395 396void 397ath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an, 398 struct ath_desc *ds, int shortPreamble, u_int8_t rix) 399{ 400 struct sample_node *sn = ATH_NODE_SAMPLE(an); 401 const struct txschedule *sched = &sn->sched[rix]; 402 const HAL_RATE_TABLE *rt = sc->sc_currates; 403 uint8_t rix1, s1code, rix2, s2code, rix3, s3code; 404 405 /* XXX precalculate short preamble tables */ 406 rix1 = sched->r1; 407 s1code = rt->info[rix1].rateCode 408 | (shortPreamble ? rt->info[rix1].shortPreamble : 0); 409 rix2 = sched->r2; 410 s2code = rt->info[rix2].rateCode 411 | (shortPreamble ? rt->info[rix2].shortPreamble : 0); 412 rix3 = sched->r3; 413 s3code = rt->info[rix3].rateCode 414 | (shortPreamble ? rt->info[rix3].shortPreamble : 0); 415 ath_hal_setupxtxdesc(sc->sc_ah, ds, 416 s1code, sched->t1, /* series 1 */ 417 s2code, sched->t2, /* series 2 */ 418 s3code, sched->t3); /* series 3 */ 419} 420 421static void 422update_stats(struct ath_softc *sc, struct ath_node *an, 423 int frame_size, 424 int rix0, int tries0, 425 int rix1, int tries1, 426 int rix2, int tries2, 427 int rix3, int tries3, 428 int short_tries, int tries, int status) 429{ 430 struct sample_node *sn = ATH_NODE_SAMPLE(an); 431 struct sample_softc *ssc = ATH_SOFTC_SAMPLE(sc); 432 const int size_bin = size_to_bin(frame_size); 433 const int size = bin_to_size(size_bin); 434 int tt, tries_so_far; 435 int is_ht40 = (an->an_node.ni_htcap & IEEE80211_HTCAP_CHWIDTH40); 436 437 if (!IS_RATE_DEFINED(sn, rix0)) 438 return; 439 tt = calc_usecs_unicast_packet(sc, size, rix0, short_tries, 440 MIN(tries0, tries) - 1, is_ht40); 441 tries_so_far = tries0; 442 443 if (tries1 && tries_so_far < tries) { 444 if (!IS_RATE_DEFINED(sn, rix1)) 445 return; 446 tt += calc_usecs_unicast_packet(sc, size, rix1, short_tries, 447 MIN(tries1 + tries_so_far, tries) - tries_so_far - 1, is_ht40); 448 tries_so_far += tries1; 449 } 450 451 if (tries2 && tries_so_far < tries) { 452 if (!IS_RATE_DEFINED(sn, rix2)) 453 return; 454 tt += calc_usecs_unicast_packet(sc, size, rix2, short_tries, 455 MIN(tries2 + tries_so_far, tries) - tries_so_far - 1, is_ht40); 456 tries_so_far += tries2; 457 } 458 459 if (tries3 && tries_so_far < tries) { 460 if (!IS_RATE_DEFINED(sn, rix3)) 461 return; 462 tt += calc_usecs_unicast_packet(sc, size, rix3, short_tries, 463 MIN(tries3 + tries_so_far, tries) - tries_so_far - 1, is_ht40); 464 } 465 466 if (sn->stats[size_bin][rix0].total_packets < ssc->smoothing_minpackets) { 467 /* just average the first few packets */ 468 int avg_tx = sn->stats[size_bin][rix0].average_tx_time; 469 int packets = sn->stats[size_bin][rix0].total_packets; 470 sn->stats[size_bin][rix0].average_tx_time = (tt+(avg_tx*packets))/(packets+1); 471 } else { 472 /* use a ewma */ 473 sn->stats[size_bin][rix0].average_tx_time = 474 ((sn->stats[size_bin][rix0].average_tx_time * ssc->smoothing_rate) + 475 (tt * (100 - ssc->smoothing_rate))) / 100; 476 } 477 478 if (status != 0) { 479 int y; 480 sn->stats[size_bin][rix0].successive_failures++; 481 for (y = size_bin+1; y < NUM_PACKET_SIZE_BINS; y++) { 482 /* 483 * Also say larger packets failed since we 484 * assume if a small packet fails at a 485 * bit-rate then a larger one will also. 486 */ 487 sn->stats[y][rix0].successive_failures++; 488 sn->stats[y][rix0].last_tx = ticks; 489 sn->stats[y][rix0].tries += tries; 490 sn->stats[y][rix0].total_packets++; 491 } 492 } else { 493 sn->stats[size_bin][rix0].packets_acked++; 494 sn->stats[size_bin][rix0].successive_failures = 0; 495 } 496 sn->stats[size_bin][rix0].tries += tries; 497 sn->stats[size_bin][rix0].last_tx = ticks; 498 sn->stats[size_bin][rix0].total_packets++; 499 500 if (rix0 == sn->current_sample_rix[size_bin]) { 501 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 502 &an->an_node, 503"%s: size %d %s sample rate %d tries (%d/%d) tt %d avg_tt (%d/%d)", 504 __func__, 505 size, 506 status ? "FAIL" : "OK", 507 rix0, short_tries, tries, tt, 508 sn->stats[size_bin][rix0].average_tx_time, 509 sn->stats[size_bin][rix0].perfect_tx_time); 510 sn->sample_tt[size_bin] = tt; 511 sn->current_sample_rix[size_bin] = -1; 512 } 513} 514 515static void 516badrate(struct ifnet *ifp, int series, int hwrate, int tries, int status) 517{ 518 if_printf(ifp, "bad series%d hwrate 0x%x, tries %u ts_status 0x%x\n", 519 series, hwrate, tries, status); 520} 521 522void 523ath_rate_tx_complete(struct ath_softc *sc, struct ath_node *an, 524 const struct ath_buf *bf) 525{ 526 struct ifnet *ifp = sc->sc_ifp; 527 struct ieee80211com *ic = ifp->if_l2com; 528 struct sample_node *sn = ATH_NODE_SAMPLE(an); 529 const struct ath_tx_status *ts = &bf->bf_status.ds_txstat; 530 const struct ath_desc *ds0 = &bf->bf_desc[0]; 531 int final_rix, short_tries, long_tries, frame_size; 532 const HAL_RATE_TABLE *rt = sc->sc_currates; 533 int mrr; 534 535 final_rix = rt->rateCodeToIndex[ts->ts_rate]; 536 short_tries = ts->ts_shortretry; 537 long_tries = ts->ts_longretry + 1; 538 frame_size = ds0->ds_ctl0 & 0x0fff; /* low-order 12 bits of ds_ctl0 */ 539 if (frame_size == 0) /* NB: should not happen */ 540 frame_size = 1500; 541 542 if (sn->ratemask == 0) { 543 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 544 &an->an_node, 545 "%s: size %d %s rate/try %d/%d no rates yet", 546 __func__, 547 bin_to_size(size_to_bin(frame_size)), 548 ts->ts_status ? "FAIL" : "OK", 549 short_tries, long_tries); 550 return; 551 } 552 mrr = sc->sc_mrretry && !(ic->ic_flags & IEEE80211_F_USEPROT); 553 if (!mrr || ts->ts_finaltsi == 0) { 554 if (!IS_RATE_DEFINED(sn, final_rix)) { 555 badrate(ifp, 0, ts->ts_rate, long_tries, ts->ts_status); 556 return; 557 } 558 /* 559 * Only one rate was used; optimize work. 560 */ 561 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 562 &an->an_node, "%s: size %d %s rate/try %d %s/%d/%d", 563 __func__, 564 bin_to_size(size_to_bin(frame_size)), 565 ts->ts_status ? "FAIL" : "OK", 566 dot11rate(rt, final_rix), dot11rate_label(rt, final_rix), short_tries, long_tries); 567 update_stats(sc, an, frame_size, 568 final_rix, long_tries, 569 0, 0, 570 0, 0, 571 0, 0, 572 short_tries, long_tries, ts->ts_status); 573 } else { 574 int hwrates[4], tries[4], rix[4]; 575 int finalTSIdx = ts->ts_finaltsi; 576 int i; 577 578 /* 579 * Process intermediate rates that failed. 580 */ 581 ath_hal_gettxcompletionrates(sc->sc_ah, ds0, hwrates, tries); 582 583 for (i = 0; i < 4; i++) { 584 rix[i] = rt->rateCodeToIndex[hwrates[i]]; 585 } 586 587 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 588 &an->an_node, 589"%s: size %d finaltsidx %d tries %d %s rate/try [%d %s/%d %d %s/%d %d %s/%d %d %s/%d]", 590 __func__, 591 bin_to_size(size_to_bin(frame_size)), 592 finalTSIdx, 593 long_tries, 594 ts->ts_status ? "FAIL" : "OK", 595 dot11rate(rt, rix[0]), dot11rate_label(rt, rix[0]), tries[0], 596 dot11rate(rt, rix[1]), dot11rate_label(rt, rix[1]), tries[1], 597 dot11rate(rt, rix[2]), dot11rate_label(rt, rix[2]), tries[2], 598 dot11rate(rt, rix[3]), dot11rate_label(rt, rix[3]), tries[3]); 599 600 for (i = 0; i < 4; i++) { 601 if (tries[i] && !IS_RATE_DEFINED(sn, rix[i])) 602 badrate(ifp, 0, hwrates[i], tries[i], ts->ts_status); 603 } 604 605 /* 606 * NB: series > 0 are not penalized for failure 607 * based on the try counts under the assumption 608 * that losses are often bursty and since we 609 * sample higher rates 1 try at a time doing so 610 * may unfairly penalize them. 611 */ 612 if (tries[0]) { 613 update_stats(sc, an, frame_size, 614 rix[0], tries[0], 615 rix[1], tries[1], 616 rix[2], tries[2], 617 rix[3], tries[3], 618 short_tries, long_tries, 619 long_tries > tries[0]); 620 long_tries -= tries[0]; 621 } 622 623 if (tries[1] && finalTSIdx > 0) { 624 update_stats(sc, an, frame_size, 625 rix[1], tries[1], 626 rix[2], tries[2], 627 rix[3], tries[3], 628 0, 0, 629 short_tries, long_tries, 630 ts->ts_status); 631 long_tries -= tries[1]; 632 } 633 634 if (tries[2] && finalTSIdx > 1) { 635 update_stats(sc, an, frame_size, 636 rix[2], tries[2], 637 rix[3], tries[3], 638 0, 0, 639 0, 0, 640 short_tries, long_tries, 641 ts->ts_status); 642 long_tries -= tries[2]; 643 } 644 645 if (tries[3] && finalTSIdx > 2) { 646 update_stats(sc, an, frame_size, 647 rix[3], tries[3], 648 0, 0, 649 0, 0, 650 0, 0, 651 short_tries, long_tries, 652 ts->ts_status); 653 } 654 } 655} 656 657void 658ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew) 659{ 660 if (isnew) 661 ath_rate_ctl_reset(sc, &an->an_node); 662} 663 664static const struct txschedule *mrr_schedules[IEEE80211_MODE_MAX+2] = { 665 NULL, /* IEEE80211_MODE_AUTO */ 666 series_11a, /* IEEE80211_MODE_11A */ 667 series_11g, /* IEEE80211_MODE_11B */ 668 series_11g, /* IEEE80211_MODE_11G */ 669 NULL, /* IEEE80211_MODE_FH */ 670 series_11a, /* IEEE80211_MODE_TURBO_A */ 671 series_11g, /* IEEE80211_MODE_TURBO_G */ 672 series_11a, /* IEEE80211_MODE_STURBO_A */ 673 series_11na, /* IEEE80211_MODE_11NA */ 674 series_11ng, /* IEEE80211_MODE_11NG */ 675 series_half, /* IEEE80211_MODE_HALF */ 676 series_quarter, /* IEEE80211_MODE_QUARTER */ 677}; 678 679/* 680 * Initialize the tables for a node. 681 */ 682static void 683ath_rate_ctl_reset(struct ath_softc *sc, struct ieee80211_node *ni) 684{ 685#define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL) 686#define DOT11RATE(_ix) (rt->info[(_ix)].dot11Rate & IEEE80211_RATE_VAL) 687#define MCS(_ix) (ni->ni_htrates.rs_rates[_ix] | IEEE80211_RATE_MCS) 688 689 struct ath_node *an = ATH_NODE(ni); 690 const struct ieee80211_txparam *tp = ni->ni_txparms; 691 struct sample_node *sn = ATH_NODE_SAMPLE(an); 692 const HAL_RATE_TABLE *rt = sc->sc_currates; 693 int x, y, srate, rix; 694 695 KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode)); 696 697 KASSERT(sc->sc_curmode < IEEE80211_MODE_MAX+2, 698 ("curmode %u", sc->sc_curmode)); 699 sn->sched = mrr_schedules[sc->sc_curmode]; 700 KASSERT(sn->sched != NULL, 701 ("no mrr schedule for mode %u", sc->sc_curmode)); 702 703 sn->static_rix = -1; 704 if (tp != NULL && tp->ucastrate != IEEE80211_FIXED_RATE_NONE) { 705 /* 706 * A fixed rate is to be used; ucastrate is the IEEE code 707 * for this rate (sans basic bit). Check this against the 708 * negotiated rate set for the node. Note the fixed rate 709 * may not be available for various reasons so we only 710 * setup the static rate index if the lookup is successful. 711 */ 712 713 /* XXX todo: check MCS rates */ 714 715 /* Check legacy rates */ 716 for (srate = ni->ni_rates.rs_nrates - 1; srate >= 0; srate--) 717 if (RATE(srate) == tp->ucastrate) { 718 sn->static_rix = sc->sc_rixmap[tp->ucastrate]; 719 break; 720 } 721#ifdef IEEE80211_DEBUG 722 if (sn->static_rix == -1) { 723 IEEE80211_NOTE(ni->ni_vap, 724 IEEE80211_MSG_RATECTL, ni, 725 "%s: ucastrate %u not found, nrates %u", 726 __func__, tp->ucastrate, 727 ni->ni_rates.rs_nrates); 728 } 729#endif 730 } 731 732 /* 733 * Construct a bitmask of usable rates. This has all 734 * negotiated rates minus those marked by the hal as 735 * to be ignored for doing rate control. 736 */ 737 sn->ratemask = 0; 738 /* MCS rates */ 739 if (ni->ni_flags & IEEE80211_NODE_HT) { 740 for (x = 0; x < ni->ni_htrates.rs_nrates; x++) { 741 rix = sc->sc_rixmap[MCS(x)]; 742 if (rix == 0xff) 743 continue; 744 /* skip rates marked broken by hal */ 745 if (!rt->info[rix].valid) 746 continue; 747 KASSERT(rix < SAMPLE_MAXRATES, 748 ("mcs %u has rix %d", MCS(x), rix)); 749 sn->ratemask |= 1<<rix; 750 } 751 } 752 753 /* Legacy rates */ 754 for (x = 0; x < ni->ni_rates.rs_nrates; x++) { 755 rix = sc->sc_rixmap[RATE(x)]; 756 if (rix == 0xff) 757 continue; 758 /* skip rates marked broken by hal */ 759 if (!rt->info[rix].valid) 760 continue; 761 KASSERT(rix < SAMPLE_MAXRATES, 762 ("rate %u has rix %d", RATE(x), rix)); 763 sn->ratemask |= 1<<rix; 764 } 765#ifdef IEEE80211_DEBUG 766 if (ieee80211_msg(ni->ni_vap, IEEE80211_MSG_RATECTL)) { 767 uint32_t mask; 768 769 ieee80211_note(ni->ni_vap, "[%6D] %s: size 1600 rate/tt", 770 ni->ni_macaddr, ":", __func__); 771 for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) { 772 if ((mask & 1) == 0) 773 continue; 774 printf(" %d %s/%d", dot11rate(rt, rix), dot11rate_label(rt, rix), 775 calc_usecs_unicast_packet(sc, 1600, rix, 0,0, 776 (ni->ni_htcap & IEEE80211_HTCAP_CHWIDTH40))); 777 } 778 printf("\n"); 779 } 780#endif 781 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) { 782 int size = bin_to_size(y); 783 uint32_t mask; 784 785 sn->packets_sent[y] = 0; 786 sn->current_sample_rix[y] = -1; 787 sn->last_sample_rix[y] = 0; 788 /* XXX start with first valid rate */ 789 sn->current_rix[y] = ffs(sn->ratemask)-1; 790 791 /* 792 * Initialize the statistics buckets; these are 793 * indexed by the rate code index. 794 */ 795 for (rix = 0, mask = sn->ratemask; mask != 0; rix++, mask >>= 1) { 796 if ((mask & 1) == 0) /* not a valid rate */ 797 continue; 798 sn->stats[y][rix].successive_failures = 0; 799 sn->stats[y][rix].tries = 0; 800 sn->stats[y][rix].total_packets = 0; 801 sn->stats[y][rix].packets_acked = 0; 802 sn->stats[y][rix].last_tx = 0; 803 804 sn->stats[y][rix].perfect_tx_time = 805 calc_usecs_unicast_packet(sc, size, rix, 0, 0, 806 (ni->ni_htcap & IEEE80211_HTCAP_CHWIDTH40)); 807 sn->stats[y][rix].average_tx_time = 808 sn->stats[y][rix].perfect_tx_time; 809 } 810 } 811#if 0 812 /* XXX 0, num_rates-1 are wrong */ 813 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, 814 "%s: %d rates %d%sMbps (%dus)- %d%sMbps (%dus)", __func__, 815 sn->num_rates, 816 DOT11RATE(0)/2, DOT11RATE(0) % 1 ? ".5" : "", 817 sn->stats[1][0].perfect_tx_time, 818 DOT11RATE(sn->num_rates-1)/2, DOT11RATE(sn->num_rates-1) % 1 ? ".5" : "", 819 sn->stats[1][sn->num_rates-1].perfect_tx_time 820 ); 821#endif 822 /* set the visible bit-rate */ 823 if (sn->static_rix != -1) 824 ni->ni_txrate = DOT11RATE(sn->static_rix); 825 else 826 ni->ni_txrate = RATE(0); 827#undef RATE 828#undef DOT11RATE 829} 830 831static void 832sample_stats(void *arg, struct ieee80211_node *ni) 833{ 834 struct ath_softc *sc = arg; 835 const HAL_RATE_TABLE *rt = sc->sc_currates; 836 struct sample_node *sn = ATH_NODE_SAMPLE(ATH_NODE(ni)); 837 uint32_t mask; 838 int rix, y; 839 840 printf("\n[%s] refcnt %d static_rix %d ratemask 0x%x\n", 841 ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni), 842 sn->static_rix, sn->ratemask); 843 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) { 844 printf("[%4u] cur rix %d (%d %s) since switch: packets %d ticks %u\n", 845 bin_to_size(y), sn->current_rix[y], 846 dot11rate(rt, sn->current_rix[y]), 847 dot11rate_label(rt, sn->current_rix[y]), 848 sn->packets_since_switch[y], sn->ticks_since_switch[y]); 849 printf("[%4u] last sample %d cur sample %d packets sent %d\n", 850 bin_to_size(y), sn->last_sample_rix[y], 851 sn->current_sample_rix[y], sn->packets_sent[y]); 852 printf("[%4u] packets since sample %d sample tt %u\n", 853 bin_to_size(y), sn->packets_since_sample[y], 854 sn->sample_tt[y]); 855 } 856 for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) { 857 if ((mask & 1) == 0) 858 continue; 859 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) { 860 if (sn->stats[y][rix].total_packets == 0) 861 continue; 862 printf("[%2u %s:%4u] %8d:%-8d (%3d%%) T %8d F %4d avg %5u last %u\n", 863 dot11rate(rt, rix), dot11rate_label(rt, rix), 864 bin_to_size(y), 865 sn->stats[y][rix].total_packets, 866 sn->stats[y][rix].packets_acked, 867 (100*sn->stats[y][rix].packets_acked)/sn->stats[y][rix].total_packets, 868 sn->stats[y][rix].tries, 869 sn->stats[y][rix].successive_failures, 870 sn->stats[y][rix].average_tx_time, 871 ticks - sn->stats[y][rix].last_tx); 872 } 873 } 874} 875 876static int 877ath_rate_sysctl_stats(SYSCTL_HANDLER_ARGS) 878{ 879 struct ath_softc *sc = arg1; 880 struct ifnet *ifp = sc->sc_ifp; 881 struct ieee80211com *ic = ifp->if_l2com; 882 int error, v; 883 884 v = 0; 885 error = sysctl_handle_int(oidp, &v, 0, req); 886 if (error || !req->newptr) 887 return error; 888 ieee80211_iterate_nodes(&ic->ic_sta, sample_stats, sc); 889 return 0; 890} 891 892static int 893ath_rate_sysctl_smoothing_rate(SYSCTL_HANDLER_ARGS) 894{ 895 struct sample_softc *ssc = arg1; 896 int rate, error; 897 898 rate = ssc->smoothing_rate; 899 error = sysctl_handle_int(oidp, &rate, 0, req); 900 if (error || !req->newptr) 901 return error; 902 if (!(0 <= rate && rate < 100)) 903 return EINVAL; 904 ssc->smoothing_rate = rate; 905 ssc->smoothing_minpackets = 100 / (100 - rate); 906 return 0; 907} 908 909static int 910ath_rate_sysctl_sample_rate(SYSCTL_HANDLER_ARGS) 911{ 912 struct sample_softc *ssc = arg1; 913 int rate, error; 914 915 rate = ssc->sample_rate; 916 error = sysctl_handle_int(oidp, &rate, 0, req); 917 if (error || !req->newptr) 918 return error; 919 if (!(2 <= rate && rate <= 100)) 920 return EINVAL; 921 ssc->sample_rate = rate; 922 return 0; 923} 924 925static void 926ath_rate_sysctlattach(struct ath_softc *sc, struct sample_softc *ssc) 927{ 928 struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev); 929 struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev); 930 931 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 932 "smoothing_rate", CTLTYPE_INT | CTLFLAG_RW, ssc, 0, 933 ath_rate_sysctl_smoothing_rate, "I", 934 "sample: smoothing rate for avg tx time (%%)"); 935 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 936 "sample_rate", CTLTYPE_INT | CTLFLAG_RW, ssc, 0, 937 ath_rate_sysctl_sample_rate, "I", 938 "sample: percent air time devoted to sampling new rates (%%)"); 939 /* XXX max_successive_failures, stale_failure_timeout, min_switch */ 940 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 941 "sample_stats", CTLTYPE_INT | CTLFLAG_RW, sc, 0, 942 ath_rate_sysctl_stats, "I", "sample: print statistics"); 943} 944 945struct ath_ratectrl * 946ath_rate_attach(struct ath_softc *sc) 947{ 948 struct sample_softc *ssc; 949 950 ssc = malloc(sizeof(struct sample_softc), M_DEVBUF, M_NOWAIT|M_ZERO); 951 if (ssc == NULL) 952 return NULL; 953 ssc->arc.arc_space = sizeof(struct sample_node); 954 ssc->smoothing_rate = 95; /* ewma percentage ([0..99]) */ 955 ssc->smoothing_minpackets = 100 / (100 - ssc->smoothing_rate); 956 ssc->sample_rate = 10; /* %time to try diff tx rates */ 957 ssc->max_successive_failures = 3; /* threshold for rate sampling*/ 958 ssc->stale_failure_timeout = 10 * hz; /* 10 seconds */ 959 ssc->min_switch = hz; /* 1 second */ 960 ath_rate_sysctlattach(sc, ssc); 961 return &ssc->arc; 962} 963 964void 965ath_rate_detach(struct ath_ratectrl *arc) 966{ 967 struct sample_softc *ssc = (struct sample_softc *) arc; 968 969 free(ssc, M_DEVBUF); 970} 971