sample.c revision 219252
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 219252 2011-03-03 20:41:59Z 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 /* XXX TODO: this doesn't know about 11gn vs 11g protection; teach it */ 277 mrr = sc->sc_mrretry && !(ic->ic_flags & IEEE80211_F_USEPROT); 278 279 best_rix = pick_best_rate(sn, rt, size_bin, !mrr); 280 if (best_rix >= 0) { 281 average_tx_time = sn->stats[size_bin][best_rix].average_tx_time; 282 } else { 283 average_tx_time = 0; 284 } 285 /* 286 * Limit the time measuring the performance of other tx 287 * rates to sample_rate% of the total transmission time. 288 */ 289 if (sn->sample_tt[size_bin] < average_tx_time * (sn->packets_since_sample[size_bin]*ssc->sample_rate/100)) { 290 rix = pick_sample_rate(ssc, sn, rt, size_bin); 291 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 292 &an->an_node, "size %u sample rate %d current rate %d", 293 bin_to_size(size_bin), RATE(rix), 294 RATE(sn->current_rix[size_bin])); 295 if (rix != sn->current_rix[size_bin]) { 296 sn->current_sample_rix[size_bin] = rix; 297 } else { 298 sn->current_sample_rix[size_bin] = -1; 299 } 300 sn->packets_since_sample[size_bin] = 0; 301 } else { 302 change_rates = 0; 303 if (!sn->packets_sent[size_bin] || best_rix == -1) { 304 /* no packet has been sent successfully yet */ 305 for (rix = rt->rateCount-1; rix > 0; rix--) { 306 if ((sn->ratemask & (1<<rix)) == 0) 307 continue; 308 /* 309 * Pick the highest rate <= 36 Mbps 310 * that hasn't failed. 311 */ 312 if (DOT11RATE(rix) <= 72 && 313 sn->stats[size_bin][rix].successive_failures == 0) { 314 break; 315 } 316 } 317 change_rates = 1; 318 best_rix = rix; 319 } else if (sn->packets_sent[size_bin] < 20) { 320 /* let the bit-rate switch quickly during the first few packets */ 321 change_rates = 1; 322 } else if (ticks - ssc->min_switch > sn->ticks_since_switch[size_bin]) { 323 /* min_switch seconds have gone by */ 324 change_rates = 1; 325 } else if (2*average_tx_time < sn->stats[size_bin][sn->current_rix[size_bin]].average_tx_time) { 326 /* the current bit-rate is twice as slow as the best one */ 327 change_rates = 1; 328 } 329 330 sn->packets_since_sample[size_bin]++; 331 332 if (change_rates) { 333 if (best_rix != sn->current_rix[size_bin]) { 334 IEEE80211_NOTE(an->an_node.ni_vap, 335 IEEE80211_MSG_RATECTL, 336 &an->an_node, 337"%s: size %d switch rate %d (%d/%d) -> %d (%d/%d) after %d packets mrr %d", 338 __func__, 339 bin_to_size(size_bin), 340 RATE(sn->current_rix[size_bin]), 341 sn->stats[size_bin][sn->current_rix[size_bin]].average_tx_time, 342 sn->stats[size_bin][sn->current_rix[size_bin]].perfect_tx_time, 343 RATE(best_rix), 344 sn->stats[size_bin][best_rix].average_tx_time, 345 sn->stats[size_bin][best_rix].perfect_tx_time, 346 sn->packets_since_switch[size_bin], 347 mrr); 348 } 349 sn->packets_since_switch[size_bin] = 0; 350 sn->current_rix[size_bin] = best_rix; 351 sn->ticks_since_switch[size_bin] = ticks; 352 /* 353 * Set the visible txrate for this node. 354 */ 355 an->an_node.ni_txrate = (rt->info[best_rix].phy == IEEE80211_T_HT) ? MCS(best_rix) : DOT11RATE(best_rix); 356 } 357 rix = sn->current_rix[size_bin]; 358 sn->packets_since_switch[size_bin]++; 359 } 360 *try0 = mrr ? sn->sched[rix].t0 : ATH_TXMAXTRY; 361done: 362 KASSERT(rix >= 0 && rix < rt->rateCount, ("rix is %d", rix)); 363 364 *rix0 = rix; 365 *txrate = rt->info[rix].rateCode 366 | (shortPreamble ? rt->info[rix].shortPreamble : 0); 367 sn->packets_sent[size_bin]++; 368#undef DOT11RATE 369#undef MCS 370#undef RATE 371} 372 373/* 374 * Get the TX rates. Don't fiddle with short preamble flags for them; 375 * the caller can do that. 376 */ 377void 378ath_rate_getxtxrates(struct ath_softc *sc, struct ath_node *an, 379 uint8_t rix0, uint8_t *rix, uint8_t *try) 380{ 381 struct sample_node *sn = ATH_NODE_SAMPLE(an); 382 const struct txschedule *sched = &sn->sched[rix0]; 383 384 KASSERT(rix0 == sched->r0, ("rix0 (%x) != sched->r0 (%x)!\n", rix0, sched->r0)); 385 386/* rix[0] = sched->r0; */ 387 rix[1] = sched->r1; 388 rix[2] = sched->r2; 389 rix[3] = sched->r3; 390 391 try[0] = sched->t0; 392 try[1] = sched->t1; 393 try[2] = sched->t2; 394 try[3] = sched->t3; 395} 396 397void 398ath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an, 399 struct ath_desc *ds, int shortPreamble, u_int8_t rix) 400{ 401 struct sample_node *sn = ATH_NODE_SAMPLE(an); 402 const struct txschedule *sched = &sn->sched[rix]; 403 const HAL_RATE_TABLE *rt = sc->sc_currates; 404 uint8_t rix1, s1code, rix2, s2code, rix3, s3code; 405 406 /* XXX precalculate short preamble tables */ 407 rix1 = sched->r1; 408 s1code = rt->info[rix1].rateCode 409 | (shortPreamble ? rt->info[rix1].shortPreamble : 0); 410 rix2 = sched->r2; 411 s2code = rt->info[rix2].rateCode 412 | (shortPreamble ? rt->info[rix2].shortPreamble : 0); 413 rix3 = sched->r3; 414 s3code = rt->info[rix3].rateCode 415 | (shortPreamble ? rt->info[rix3].shortPreamble : 0); 416 ath_hal_setupxtxdesc(sc->sc_ah, ds, 417 s1code, sched->t1, /* series 1 */ 418 s2code, sched->t2, /* series 2 */ 419 s3code, sched->t3); /* series 3 */ 420} 421 422static void 423update_stats(struct ath_softc *sc, struct ath_node *an, 424 int frame_size, 425 int rix0, int tries0, 426 int rix1, int tries1, 427 int rix2, int tries2, 428 int rix3, int tries3, 429 int short_tries, int tries, int status) 430{ 431 struct sample_node *sn = ATH_NODE_SAMPLE(an); 432 struct sample_softc *ssc = ATH_SOFTC_SAMPLE(sc); 433 const int size_bin = size_to_bin(frame_size); 434 const int size = bin_to_size(size_bin); 435 int tt, tries_so_far; 436 int is_ht40 = (an->an_node.ni_htcap & IEEE80211_HTCAP_CHWIDTH40); 437 438 if (!IS_RATE_DEFINED(sn, rix0)) 439 return; 440 tt = calc_usecs_unicast_packet(sc, size, rix0, short_tries, 441 MIN(tries0, tries) - 1, is_ht40); 442 tries_so_far = tries0; 443 444 if (tries1 && tries_so_far < tries) { 445 if (!IS_RATE_DEFINED(sn, rix1)) 446 return; 447 tt += calc_usecs_unicast_packet(sc, size, rix1, short_tries, 448 MIN(tries1 + tries_so_far, tries) - tries_so_far - 1, is_ht40); 449 tries_so_far += tries1; 450 } 451 452 if (tries2 && tries_so_far < tries) { 453 if (!IS_RATE_DEFINED(sn, rix2)) 454 return; 455 tt += calc_usecs_unicast_packet(sc, size, rix2, short_tries, 456 MIN(tries2 + tries_so_far, tries) - tries_so_far - 1, is_ht40); 457 tries_so_far += tries2; 458 } 459 460 if (tries3 && tries_so_far < tries) { 461 if (!IS_RATE_DEFINED(sn, rix3)) 462 return; 463 tt += calc_usecs_unicast_packet(sc, size, rix3, short_tries, 464 MIN(tries3 + tries_so_far, tries) - tries_so_far - 1, is_ht40); 465 } 466 467 if (sn->stats[size_bin][rix0].total_packets < ssc->smoothing_minpackets) { 468 /* just average the first few packets */ 469 int avg_tx = sn->stats[size_bin][rix0].average_tx_time; 470 int packets = sn->stats[size_bin][rix0].total_packets; 471 sn->stats[size_bin][rix0].average_tx_time = (tt+(avg_tx*packets))/(packets+1); 472 } else { 473 /* use a ewma */ 474 sn->stats[size_bin][rix0].average_tx_time = 475 ((sn->stats[size_bin][rix0].average_tx_time * ssc->smoothing_rate) + 476 (tt * (100 - ssc->smoothing_rate))) / 100; 477 } 478 479 if (status != 0) { 480 int y; 481 sn->stats[size_bin][rix0].successive_failures++; 482 for (y = size_bin+1; y < NUM_PACKET_SIZE_BINS; y++) { 483 /* 484 * Also say larger packets failed since we 485 * assume if a small packet fails at a 486 * bit-rate then a larger one will also. 487 */ 488 sn->stats[y][rix0].successive_failures++; 489 sn->stats[y][rix0].last_tx = ticks; 490 sn->stats[y][rix0].tries += tries; 491 sn->stats[y][rix0].total_packets++; 492 } 493 } else { 494 sn->stats[size_bin][rix0].packets_acked++; 495 sn->stats[size_bin][rix0].successive_failures = 0; 496 } 497 sn->stats[size_bin][rix0].tries += tries; 498 sn->stats[size_bin][rix0].last_tx = ticks; 499 sn->stats[size_bin][rix0].total_packets++; 500 501 if (rix0 == sn->current_sample_rix[size_bin]) { 502 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 503 &an->an_node, 504"%s: size %d %s sample rate %d tries (%d/%d) tt %d avg_tt (%d/%d)", 505 __func__, 506 size, 507 status ? "FAIL" : "OK", 508 rix0, short_tries, tries, tt, 509 sn->stats[size_bin][rix0].average_tx_time, 510 sn->stats[size_bin][rix0].perfect_tx_time); 511 sn->sample_tt[size_bin] = tt; 512 sn->current_sample_rix[size_bin] = -1; 513 } 514} 515 516static void 517badrate(struct ifnet *ifp, int series, int hwrate, int tries, int status) 518{ 519 if_printf(ifp, "bad series%d hwrate 0x%x, tries %u ts_status 0x%x\n", 520 series, hwrate, tries, status); 521} 522 523void 524ath_rate_tx_complete(struct ath_softc *sc, struct ath_node *an, 525 const struct ath_buf *bf) 526{ 527 struct ifnet *ifp = sc->sc_ifp; 528 struct ieee80211com *ic = ifp->if_l2com; 529 struct sample_node *sn = ATH_NODE_SAMPLE(an); 530 const struct ath_tx_status *ts = &bf->bf_status.ds_txstat; 531 const struct ath_desc *ds0 = &bf->bf_desc[0]; 532 int final_rix, short_tries, long_tries, frame_size; 533 const HAL_RATE_TABLE *rt = sc->sc_currates; 534 int mrr; 535 536 final_rix = rt->rateCodeToIndex[ts->ts_rate]; 537 short_tries = ts->ts_shortretry; 538 long_tries = ts->ts_longretry + 1; 539 frame_size = ds0->ds_ctl0 & 0x0fff; /* low-order 12 bits of ds_ctl0 */ 540 if (frame_size == 0) /* NB: should not happen */ 541 frame_size = 1500; 542 543 if (sn->ratemask == 0) { 544 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 545 &an->an_node, 546 "%s: size %d %s rate/try %d/%d no rates yet", 547 __func__, 548 bin_to_size(size_to_bin(frame_size)), 549 ts->ts_status ? "FAIL" : "OK", 550 short_tries, long_tries); 551 return; 552 } 553 mrr = sc->sc_mrretry && !(ic->ic_flags & IEEE80211_F_USEPROT); 554 if (!mrr || ts->ts_finaltsi == 0) { 555 if (!IS_RATE_DEFINED(sn, final_rix)) { 556 badrate(ifp, 0, ts->ts_rate, long_tries, ts->ts_status); 557 return; 558 } 559 /* 560 * Only one rate was used; optimize work. 561 */ 562 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 563 &an->an_node, "%s: size %d %s rate/try %d %s/%d/%d", 564 __func__, 565 bin_to_size(size_to_bin(frame_size)), 566 ts->ts_status ? "FAIL" : "OK", 567 dot11rate(rt, final_rix), dot11rate_label(rt, final_rix), short_tries, long_tries); 568 update_stats(sc, an, frame_size, 569 final_rix, long_tries, 570 0, 0, 571 0, 0, 572 0, 0, 573 short_tries, long_tries, ts->ts_status); 574 } else { 575 int hwrates[4], tries[4], rix[4]; 576 int finalTSIdx = ts->ts_finaltsi; 577 int i; 578 579 /* 580 * Process intermediate rates that failed. 581 */ 582 ath_hal_gettxcompletionrates(sc->sc_ah, ds0, hwrates, tries); 583 584 for (i = 0; i < 4; i++) { 585 rix[i] = rt->rateCodeToIndex[hwrates[i]]; 586 } 587 588 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 589 &an->an_node, 590"%s: size %d finaltsidx %d tries %d %s rate/try [%d %s/%d %d %s/%d %d %s/%d %d %s/%d]", 591 __func__, 592 bin_to_size(size_to_bin(frame_size)), 593 finalTSIdx, 594 long_tries, 595 ts->ts_status ? "FAIL" : "OK", 596 dot11rate(rt, rix[0]), dot11rate_label(rt, rix[0]), tries[0], 597 dot11rate(rt, rix[1]), dot11rate_label(rt, rix[1]), tries[1], 598 dot11rate(rt, rix[2]), dot11rate_label(rt, rix[2]), tries[2], 599 dot11rate(rt, rix[3]), dot11rate_label(rt, rix[3]), tries[3]); 600 601 for (i = 0; i < 4; i++) { 602 if (tries[i] && !IS_RATE_DEFINED(sn, rix[i])) 603 badrate(ifp, 0, hwrates[i], tries[i], ts->ts_status); 604 } 605 606 /* 607 * NB: series > 0 are not penalized for failure 608 * based on the try counts under the assumption 609 * that losses are often bursty and since we 610 * sample higher rates 1 try at a time doing so 611 * may unfairly penalize them. 612 */ 613 if (tries[0]) { 614 update_stats(sc, an, frame_size, 615 rix[0], tries[0], 616 rix[1], tries[1], 617 rix[2], tries[2], 618 rix[3], tries[3], 619 short_tries, long_tries, 620 long_tries > tries[0]); 621 long_tries -= tries[0]; 622 } 623 624 if (tries[1] && finalTSIdx > 0) { 625 update_stats(sc, an, frame_size, 626 rix[1], tries[1], 627 rix[2], tries[2], 628 rix[3], tries[3], 629 0, 0, 630 short_tries, long_tries, 631 ts->ts_status); 632 long_tries -= tries[1]; 633 } 634 635 if (tries[2] && finalTSIdx > 1) { 636 update_stats(sc, an, frame_size, 637 rix[2], tries[2], 638 rix[3], tries[3], 639 0, 0, 640 0, 0, 641 short_tries, long_tries, 642 ts->ts_status); 643 long_tries -= tries[2]; 644 } 645 646 if (tries[3] && finalTSIdx > 2) { 647 update_stats(sc, an, frame_size, 648 rix[3], tries[3], 649 0, 0, 650 0, 0, 651 0, 0, 652 short_tries, long_tries, 653 ts->ts_status); 654 } 655 } 656} 657 658void 659ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew) 660{ 661 if (isnew) 662 ath_rate_ctl_reset(sc, &an->an_node); 663} 664 665static const struct txschedule *mrr_schedules[IEEE80211_MODE_MAX+2] = { 666 NULL, /* IEEE80211_MODE_AUTO */ 667 series_11a, /* IEEE80211_MODE_11A */ 668 series_11g, /* IEEE80211_MODE_11B */ 669 series_11g, /* IEEE80211_MODE_11G */ 670 NULL, /* IEEE80211_MODE_FH */ 671 series_11a, /* IEEE80211_MODE_TURBO_A */ 672 series_11g, /* IEEE80211_MODE_TURBO_G */ 673 series_11a, /* IEEE80211_MODE_STURBO_A */ 674 series_11na, /* IEEE80211_MODE_11NA */ 675 series_11ng, /* IEEE80211_MODE_11NG */ 676 series_half, /* IEEE80211_MODE_HALF */ 677 series_quarter, /* IEEE80211_MODE_QUARTER */ 678}; 679 680/* 681 * Initialize the tables for a node. 682 */ 683static void 684ath_rate_ctl_reset(struct ath_softc *sc, struct ieee80211_node *ni) 685{ 686#define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL) 687#define DOT11RATE(_ix) (rt->info[(_ix)].dot11Rate & IEEE80211_RATE_VAL) 688#define MCS(_ix) (ni->ni_htrates.rs_rates[_ix] | IEEE80211_RATE_MCS) 689 690 struct ath_node *an = ATH_NODE(ni); 691 const struct ieee80211_txparam *tp = ni->ni_txparms; 692 struct sample_node *sn = ATH_NODE_SAMPLE(an); 693 const HAL_RATE_TABLE *rt = sc->sc_currates; 694 int x, y, srate, rix; 695 696 KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode)); 697 698 KASSERT(sc->sc_curmode < IEEE80211_MODE_MAX+2, 699 ("curmode %u", sc->sc_curmode)); 700 sn->sched = mrr_schedules[sc->sc_curmode]; 701 KASSERT(sn->sched != NULL, 702 ("no mrr schedule for mode %u", sc->sc_curmode)); 703 704 sn->static_rix = -1; 705 if (tp != NULL && tp->ucastrate != IEEE80211_FIXED_RATE_NONE) { 706 /* 707 * A fixed rate is to be used; ucastrate is the IEEE code 708 * for this rate (sans basic bit). Check this against the 709 * negotiated rate set for the node. Note the fixed rate 710 * may not be available for various reasons so we only 711 * setup the static rate index if the lookup is successful. 712 */ 713 714 /* XXX todo: check MCS rates */ 715 716 /* Check legacy rates */ 717 for (srate = ni->ni_rates.rs_nrates - 1; srate >= 0; srate--) 718 if (RATE(srate) == tp->ucastrate) { 719 sn->static_rix = sc->sc_rixmap[tp->ucastrate]; 720 break; 721 } 722#ifdef IEEE80211_DEBUG 723 if (sn->static_rix == -1) { 724 IEEE80211_NOTE(ni->ni_vap, 725 IEEE80211_MSG_RATECTL, ni, 726 "%s: ucastrate %u not found, nrates %u", 727 __func__, tp->ucastrate, 728 ni->ni_rates.rs_nrates); 729 } 730#endif 731 } 732 733 /* 734 * Construct a bitmask of usable rates. This has all 735 * negotiated rates minus those marked by the hal as 736 * to be ignored for doing rate control. 737 */ 738 sn->ratemask = 0; 739 /* MCS rates */ 740 if (ni->ni_flags & IEEE80211_NODE_HT) { 741 for (x = 0; x < ni->ni_htrates.rs_nrates; x++) { 742 rix = sc->sc_rixmap[MCS(x)]; 743 if (rix == 0xff) 744 continue; 745 /* skip rates marked broken by hal */ 746 if (!rt->info[rix].valid) 747 continue; 748 KASSERT(rix < SAMPLE_MAXRATES, 749 ("mcs %u has rix %d", MCS(x), rix)); 750 sn->ratemask |= 1<<rix; 751 } 752 } 753 754 /* Legacy rates */ 755 for (x = 0; x < ni->ni_rates.rs_nrates; x++) { 756 rix = sc->sc_rixmap[RATE(x)]; 757 if (rix == 0xff) 758 continue; 759 /* skip rates marked broken by hal */ 760 if (!rt->info[rix].valid) 761 continue; 762 KASSERT(rix < SAMPLE_MAXRATES, 763 ("rate %u has rix %d", RATE(x), rix)); 764 sn->ratemask |= 1<<rix; 765 } 766#ifdef IEEE80211_DEBUG 767 if (ieee80211_msg(ni->ni_vap, IEEE80211_MSG_RATECTL)) { 768 uint32_t mask; 769 770 ieee80211_note(ni->ni_vap, "[%6D] %s: size 1600 rate/tt", 771 ni->ni_macaddr, ":", __func__); 772 for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) { 773 if ((mask & 1) == 0) 774 continue; 775 printf(" %d %s/%d", dot11rate(rt, rix), dot11rate_label(rt, rix), 776 calc_usecs_unicast_packet(sc, 1600, rix, 0,0, 777 (ni->ni_htcap & IEEE80211_HTCAP_CHWIDTH40))); 778 } 779 printf("\n"); 780 } 781#endif 782 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) { 783 int size = bin_to_size(y); 784 uint32_t mask; 785 786 sn->packets_sent[y] = 0; 787 sn->current_sample_rix[y] = -1; 788 sn->last_sample_rix[y] = 0; 789 /* XXX start with first valid rate */ 790 sn->current_rix[y] = ffs(sn->ratemask)-1; 791 792 /* 793 * Initialize the statistics buckets; these are 794 * indexed by the rate code index. 795 */ 796 for (rix = 0, mask = sn->ratemask; mask != 0; rix++, mask >>= 1) { 797 if ((mask & 1) == 0) /* not a valid rate */ 798 continue; 799 sn->stats[y][rix].successive_failures = 0; 800 sn->stats[y][rix].tries = 0; 801 sn->stats[y][rix].total_packets = 0; 802 sn->stats[y][rix].packets_acked = 0; 803 sn->stats[y][rix].last_tx = 0; 804 805 sn->stats[y][rix].perfect_tx_time = 806 calc_usecs_unicast_packet(sc, size, rix, 0, 0, 807 (ni->ni_htcap & IEEE80211_HTCAP_CHWIDTH40)); 808 sn->stats[y][rix].average_tx_time = 809 sn->stats[y][rix].perfect_tx_time; 810 } 811 } 812#if 0 813 /* XXX 0, num_rates-1 are wrong */ 814 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, 815 "%s: %d rates %d%sMbps (%dus)- %d%sMbps (%dus)", __func__, 816 sn->num_rates, 817 DOT11RATE(0)/2, DOT11RATE(0) % 1 ? ".5" : "", 818 sn->stats[1][0].perfect_tx_time, 819 DOT11RATE(sn->num_rates-1)/2, DOT11RATE(sn->num_rates-1) % 1 ? ".5" : "", 820 sn->stats[1][sn->num_rates-1].perfect_tx_time 821 ); 822#endif 823 /* set the visible bit-rate */ 824 if (sn->static_rix != -1) 825 ni->ni_txrate = DOT11RATE(sn->static_rix); 826 else 827 ni->ni_txrate = RATE(0); 828#undef RATE 829#undef DOT11RATE 830} 831 832static void 833sample_stats(void *arg, struct ieee80211_node *ni) 834{ 835 struct ath_softc *sc = arg; 836 const HAL_RATE_TABLE *rt = sc->sc_currates; 837 struct sample_node *sn = ATH_NODE_SAMPLE(ATH_NODE(ni)); 838 uint32_t mask; 839 int rix, y; 840 841 printf("\n[%s] refcnt %d static_rix %d ratemask 0x%x\n", 842 ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni), 843 sn->static_rix, sn->ratemask); 844 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) { 845 printf("[%4u] cur rix %d (%d %s) since switch: packets %d ticks %u\n", 846 bin_to_size(y), sn->current_rix[y], 847 dot11rate(rt, sn->current_rix[y]), 848 dot11rate_label(rt, sn->current_rix[y]), 849 sn->packets_since_switch[y], sn->ticks_since_switch[y]); 850 printf("[%4u] last sample %d cur sample %d packets sent %d\n", 851 bin_to_size(y), sn->last_sample_rix[y], 852 sn->current_sample_rix[y], sn->packets_sent[y]); 853 printf("[%4u] packets since sample %d sample tt %u\n", 854 bin_to_size(y), sn->packets_since_sample[y], 855 sn->sample_tt[y]); 856 } 857 for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) { 858 if ((mask & 1) == 0) 859 continue; 860 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) { 861 if (sn->stats[y][rix].total_packets == 0) 862 continue; 863 printf("[%2u %s:%4u] %8d:%-8d (%3d%%) T %8d F %4d avg %5u last %u\n", 864 dot11rate(rt, rix), dot11rate_label(rt, rix), 865 bin_to_size(y), 866 sn->stats[y][rix].total_packets, 867 sn->stats[y][rix].packets_acked, 868 (100*sn->stats[y][rix].packets_acked)/sn->stats[y][rix].total_packets, 869 sn->stats[y][rix].tries, 870 sn->stats[y][rix].successive_failures, 871 sn->stats[y][rix].average_tx_time, 872 ticks - sn->stats[y][rix].last_tx); 873 } 874 } 875} 876 877static int 878ath_rate_sysctl_stats(SYSCTL_HANDLER_ARGS) 879{ 880 struct ath_softc *sc = arg1; 881 struct ifnet *ifp = sc->sc_ifp; 882 struct ieee80211com *ic = ifp->if_l2com; 883 int error, v; 884 885 v = 0; 886 error = sysctl_handle_int(oidp, &v, 0, req); 887 if (error || !req->newptr) 888 return error; 889 ieee80211_iterate_nodes(&ic->ic_sta, sample_stats, sc); 890 return 0; 891} 892 893static int 894ath_rate_sysctl_smoothing_rate(SYSCTL_HANDLER_ARGS) 895{ 896 struct sample_softc *ssc = arg1; 897 int rate, error; 898 899 rate = ssc->smoothing_rate; 900 error = sysctl_handle_int(oidp, &rate, 0, req); 901 if (error || !req->newptr) 902 return error; 903 if (!(0 <= rate && rate < 100)) 904 return EINVAL; 905 ssc->smoothing_rate = rate; 906 ssc->smoothing_minpackets = 100 / (100 - rate); 907 return 0; 908} 909 910static int 911ath_rate_sysctl_sample_rate(SYSCTL_HANDLER_ARGS) 912{ 913 struct sample_softc *ssc = arg1; 914 int rate, error; 915 916 rate = ssc->sample_rate; 917 error = sysctl_handle_int(oidp, &rate, 0, req); 918 if (error || !req->newptr) 919 return error; 920 if (!(2 <= rate && rate <= 100)) 921 return EINVAL; 922 ssc->sample_rate = rate; 923 return 0; 924} 925 926static void 927ath_rate_sysctlattach(struct ath_softc *sc, struct sample_softc *ssc) 928{ 929 struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev); 930 struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev); 931 932 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 933 "smoothing_rate", CTLTYPE_INT | CTLFLAG_RW, ssc, 0, 934 ath_rate_sysctl_smoothing_rate, "I", 935 "sample: smoothing rate for avg tx time (%%)"); 936 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 937 "sample_rate", CTLTYPE_INT | CTLFLAG_RW, ssc, 0, 938 ath_rate_sysctl_sample_rate, "I", 939 "sample: percent air time devoted to sampling new rates (%%)"); 940 /* XXX max_successive_failures, stale_failure_timeout, min_switch */ 941 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 942 "sample_stats", CTLTYPE_INT | CTLFLAG_RW, sc, 0, 943 ath_rate_sysctl_stats, "I", "sample: print statistics"); 944} 945 946struct ath_ratectrl * 947ath_rate_attach(struct ath_softc *sc) 948{ 949 struct sample_softc *ssc; 950 951 ssc = malloc(sizeof(struct sample_softc), M_DEVBUF, M_NOWAIT|M_ZERO); 952 if (ssc == NULL) 953 return NULL; 954 ssc->arc.arc_space = sizeof(struct sample_node); 955 ssc->smoothing_rate = 95; /* ewma percentage ([0..99]) */ 956 ssc->smoothing_minpackets = 100 / (100 - ssc->smoothing_rate); 957 ssc->sample_rate = 10; /* %time to try diff tx rates */ 958 ssc->max_successive_failures = 3; /* threshold for rate sampling*/ 959 ssc->stale_failure_timeout = 10 * hz; /* 10 seconds */ 960 ssc->min_switch = hz; /* 1 second */ 961 ath_rate_sysctlattach(sc, ssc); 962 return &ssc->arc; 963} 964 965void 966ath_rate_detach(struct ath_ratectrl *arc) 967{ 968 struct sample_softc *ssc = (struct sample_softc *) arc; 969 970 free(ssc, M_DEVBUF); 971} 972