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("$FreeBSD$"); 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 */ 103 104 static void ath_rate_ctl_reset(struct ath_softc *, struct ieee80211_node *); 105 106 static const int packet_size_bins[NUM_PACKET_SIZE_BINS] = { 250, 1600 }; 107 108 static __inline int 109 size_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 } 128 129 static __inline int 130 bin_to_size(int index) 131 { 132 return packet_size_bins[index]; 133 } 134 135 void 136 ath_rate_node_init(struct ath_softc *sc, struct ath_node *an) 137 { 138 /* NB: assumed to be zero'd by caller */ 139 } 140 141 void 142 ath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an) 143 { 144 } 145 146 static int 147 dot11rate(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 } 152 153 static const char * 154 dot11rate_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 */ 163 static __inline int 164 pick_best_rate(struct ath_node *an, const HAL_RATE_TABLE *rt, 165 int size_bin, int require_acked_before) 166 { 167 struct sample_node *sn = ATH_NODE_SAMPLE(an); 168 int best_rate_rix, best_rate_tt; 169 uint32_t mask; 170 int rix, tt; 171 172 best_rate_rix = 0; 173 best_rate_tt = 0; 174 for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) { 175 if ((mask & 1) == 0) /* not a supported rate */ 176 continue; 177 178 /* Don't pick a non-HT rate for a HT node */ 179 if ((an->an_node.ni_flags & IEEE80211_NODE_HT) && 180 (rt->info[rix].phy != IEEE80211_T_HT)) { 181 continue; 182 } 183 184 tt = sn->stats[size_bin][rix].average_tx_time; 185 if (tt <= 0 || 186 (require_acked_before && 187 !sn->stats[size_bin][rix].packets_acked)) 188 continue; 189 190 /* don't use a bit-rate that has been failing */ 191 if (sn->stats[size_bin][rix].successive_failures > 3) 192 continue; 193 194 if (best_rate_tt == 0 || tt < best_rate_tt) { 195 best_rate_tt = tt; 196 best_rate_rix = rix; 197 } 198 } 199 return (best_rate_tt ? best_rate_rix : -1); 200 } 201 202 /* 203 * Pick a good "random" bit-rate to sample other than the current one. 204 */ 205 static __inline int 206 pick_sample_rate(struct sample_softc *ssc , struct ath_node *an, 207 const HAL_RATE_TABLE *rt, int size_bin) 208 { 209 #define DOT11RATE(ix) (rt->info[ix].dot11Rate & IEEE80211_RATE_VAL) 210 #define MCS(ix) (rt->info[ix].dot11Rate | IEEE80211_RATE_MCS) 211 struct sample_node *sn = ATH_NODE_SAMPLE(an); 212 int current_rix, rix; 213 unsigned current_tt; 214 uint32_t mask; 215 216 current_rix = sn->current_rix[size_bin]; 217 if (current_rix < 0) { 218 /* no successes yet, send at the lowest bit-rate */ 219 /* XXX should return MCS0 if HT */ 220 return 0; 221 } 222 223 current_tt = sn->stats[size_bin][current_rix].average_tx_time; 224 225 rix = sn->last_sample_rix[size_bin]+1; /* next sample rate */ 226 mask = sn->ratemask &~ (1<<current_rix);/* don't sample current rate */ 227 while (mask != 0) { 228 if ((mask & (1<<rix)) == 0) { /* not a supported rate */ 229 nextrate: 230 if (++rix >= rt->rateCount) 231 rix = 0; 232 continue; 233 } 234 235 /* if the node is HT and the rate isn't HT, don't bother sample */ 236 if ((an->an_node.ni_flags & IEEE80211_NODE_HT) && 237 (rt->info[rix].phy != IEEE80211_T_HT)) { 238 mask &= ~(1<<rix); 239 goto nextrate; 240 } 241 242 /* this bit-rate is always worse than the current one */ 243 if (sn->stats[size_bin][rix].perfect_tx_time > current_tt) { 244 mask &= ~(1<<rix); 245 goto nextrate; 246 } 247 248 /* rarely sample bit-rates that fail a lot */ 249 if (sn->stats[size_bin][rix].successive_failures > ssc->max_successive_failures && 250 ticks - sn->stats[size_bin][rix].last_tx < ssc->stale_failure_timeout) { 251 mask &= ~(1<<rix); 252 goto nextrate; 253 } 254 255 /* Don't sample more than 2 rates higher for rates > 11M for non-HT rates */ 256 if (! (an->an_node.ni_flags & IEEE80211_NODE_HT)) { 257 if (DOT11RATE(rix) > 2*11 && rix > current_rix + 2) { 258 mask &= ~(1<<rix); 259 goto nextrate; 260 } 261 } 262 263 sn->last_sample_rix[size_bin] = rix; 264 return rix; 265 } 266 return current_rix; 267 #undef DOT11RATE 268 #undef MCS 269 } 270 271 static int 272 ath_rate_get_static_rix(struct ath_softc *sc, const struct ieee80211_node *ni) 273 { 274 #define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL) 275 #define DOT11RATE(_ix) (rt->info[(_ix)].dot11Rate & IEEE80211_RATE_VAL) 276 #define MCS(_ix) (ni->ni_htrates.rs_rates[_ix] | IEEE80211_RATE_MCS) 277 const struct ieee80211_txparam *tp = ni->ni_txparms; 278 int srate; 279 280 /* Check MCS rates */ 281 for (srate = ni->ni_htrates.rs_nrates - 1; srate >= 0; srate--) { 282 if (MCS(srate) == tp->ucastrate) 283 return sc->sc_rixmap[tp->ucastrate]; 284 } 285 286 /* Check legacy rates */ 287 for (srate = ni->ni_rates.rs_nrates - 1; srate >= 0; srate--) { 288 if (RATE(srate) == tp->ucastrate) 289 return sc->sc_rixmap[tp->ucastrate]; 290 } 291 return -1; 292 #undef RATE 293 #undef DOT11RATE 294 #undef MCS 295 } 296 297 static void 298 ath_rate_update_static_rix(struct ath_softc *sc, struct ieee80211_node *ni) 299 { 300 struct ath_node *an = ATH_NODE(ni); 301 const struct ieee80211_txparam *tp = ni->ni_txparms; 302 struct sample_node *sn = ATH_NODE_SAMPLE(an); 303 304 if (tp != NULL && tp->ucastrate != IEEE80211_FIXED_RATE_NONE) { 305 /* 306 * A fixed rate is to be used; ucastrate is the IEEE code 307 * for this rate (sans basic bit). Check this against the 308 * negotiated rate set for the node. Note the fixed rate 309 * may not be available for various reasons so we only 310 * setup the static rate index if the lookup is successful. 311 */ 312 sn->static_rix = ath_rate_get_static_rix(sc, ni); 313 } else { 314 sn->static_rix = -1; 315 } 316 } 317 318 319 320 void 321 ath_rate_findrate(struct ath_softc *sc, struct ath_node *an, 322 int shortPreamble, size_t frameLen, 323 u_int8_t *rix0, int *try0, u_int8_t *txrate) 324 { 325 #define DOT11RATE(ix) (rt->info[ix].dot11Rate & IEEE80211_RATE_VAL) 326 #define MCS(ix) (rt->info[ix].dot11Rate | IEEE80211_RATE_MCS) 327 #define RATE(ix) (DOT11RATE(ix) / 2) 328 struct sample_node *sn = ATH_NODE_SAMPLE(an); 329 struct sample_softc *ssc = ATH_SOFTC_SAMPLE(sc); 330 struct ifnet *ifp = sc->sc_ifp; 331 struct ieee80211com *ic = ifp->if_l2com; 332 const HAL_RATE_TABLE *rt = sc->sc_currates; 333 const int size_bin = size_to_bin(frameLen); 334 int rix, mrr, best_rix, change_rates; 335 unsigned average_tx_time; 336 337 ath_rate_update_static_rix(sc, &an->an_node); 338 339 if (sn->static_rix != -1) { 340 rix = sn->static_rix; 341 *try0 = ATH_TXMAXTRY; 342 goto done; 343 } 344 345 /* XXX TODO: this doesn't know about 11gn vs 11g protection; teach it */ 346 mrr = sc->sc_mrretry && !(ic->ic_flags & IEEE80211_F_USEPROT); 347 348 best_rix = pick_best_rate(an, rt, size_bin, !mrr); 349 if (best_rix >= 0) { 350 average_tx_time = sn->stats[size_bin][best_rix].average_tx_time; 351 } else { 352 average_tx_time = 0; 353 } 354 /* 355 * Limit the time measuring the performance of other tx 356 * rates to sample_rate% of the total transmission time. 357 */ 358 if (sn->sample_tt[size_bin] < average_tx_time * (sn->packets_since_sample[size_bin]*ssc->sample_rate/100)) { 359 rix = pick_sample_rate(ssc, an, rt, size_bin); 360 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 361 &an->an_node, "size %u sample rate %d current rate %d", 362 bin_to_size(size_bin), RATE(rix), 363 RATE(sn->current_rix[size_bin])); 364 if (rix != sn->current_rix[size_bin]) { 365 sn->current_sample_rix[size_bin] = rix; 366 } else { 367 sn->current_sample_rix[size_bin] = -1; 368 } 369 sn->packets_since_sample[size_bin] = 0; 370 } else { 371 change_rates = 0; 372 if (!sn->packets_sent[size_bin] || best_rix == -1) { 373 /* no packet has been sent successfully yet */ 374 for (rix = rt->rateCount-1; rix > 0; rix--) { 375 if ((sn->ratemask & (1<<rix)) == 0) 376 continue; 377 /* 378 * Pick the highest rate <= 36 Mbps 379 * that hasn't failed. 380 */ 381 if (DOT11RATE(rix) <= 72 && 382 sn->stats[size_bin][rix].successive_failures == 0) { 383 break; 384 } 385 } 386 change_rates = 1; 387 best_rix = rix; 388 } else if (sn->packets_sent[size_bin] < 20) { 389 /* let the bit-rate switch quickly during the first few packets */ 390 change_rates = 1; 391 } else if (ticks - ssc->min_switch > sn->ticks_since_switch[size_bin]) { 392 /* min_switch seconds have gone by */ 393 change_rates = 1; 394 } else if (2*average_tx_time < sn->stats[size_bin][sn->current_rix[size_bin]].average_tx_time) { 395 /* the current bit-rate is twice as slow as the best one */ 396 change_rates = 1; 397 } 398 399 sn->packets_since_sample[size_bin]++; 400 401 if (change_rates) { 402 if (best_rix != sn->current_rix[size_bin]) { 403 IEEE80211_NOTE(an->an_node.ni_vap, 404 IEEE80211_MSG_RATECTL, 405 &an->an_node, 406 "%s: size %d switch rate %d (%d/%d) -> %d (%d/%d) after %d packets mrr %d", 407 __func__, 408 bin_to_size(size_bin), 409 RATE(sn->current_rix[size_bin]), 410 sn->stats[size_bin][sn->current_rix[size_bin]].average_tx_time, 411 sn->stats[size_bin][sn->current_rix[size_bin]].perfect_tx_time, 412 RATE(best_rix), 413 sn->stats[size_bin][best_rix].average_tx_time, 414 sn->stats[size_bin][best_rix].perfect_tx_time, 415 sn->packets_since_switch[size_bin], 416 mrr); 417 } 418 sn->packets_since_switch[size_bin] = 0; 419 sn->current_rix[size_bin] = best_rix; 420 sn->ticks_since_switch[size_bin] = ticks; 421 /* 422 * Set the visible txrate for this node. 423 */ 424 an->an_node.ni_txrate = (rt->info[best_rix].phy == IEEE80211_T_HT) ? MCS(best_rix) : DOT11RATE(best_rix); 425 } 426 rix = sn->current_rix[size_bin]; 427 sn->packets_since_switch[size_bin]++; 428 } 429 *try0 = mrr ? sn->sched[rix].t0 : ATH_TXMAXTRY; 430 done: 431 KASSERT(rix >= 0 && rix < rt->rateCount, ("rix is %d", rix)); 432 433 *rix0 = rix; 434 *txrate = rt->info[rix].rateCode 435 | (shortPreamble ? rt->info[rix].shortPreamble : 0); 436 sn->packets_sent[size_bin]++; 437 #undef DOT11RATE 438 #undef MCS 439 #undef RATE 440 } 441 442 /* 443 * Get the TX rates. Don't fiddle with short preamble flags for them; 444 * the caller can do that. 445 */ 446 void 447 ath_rate_getxtxrates(struct ath_softc *sc, struct ath_node *an, 448 uint8_t rix0, uint8_t *rix, uint8_t *try) 449 { 450 struct sample_node *sn = ATH_NODE_SAMPLE(an); 451 const struct txschedule *sched = &sn->sched[rix0]; 452 453 KASSERT(rix0 == sched->r0, ("rix0 (%x) != sched->r0 (%x)!\n", rix0, sched->r0)); 454 455 /* rix[0] = sched->r0; */ 456 rix[1] = sched->r1; 457 rix[2] = sched->r2; 458 rix[3] = sched->r3; 459 460 try[0] = sched->t0; 461 try[1] = sched->t1; 462 try[2] = sched->t2; 463 try[3] = sched->t3; 464 } 465 466 void 467 ath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an, 468 struct ath_desc *ds, int shortPreamble, u_int8_t rix) 469 { 470 struct sample_node *sn = ATH_NODE_SAMPLE(an); 471 const struct txschedule *sched = &sn->sched[rix]; 472 const HAL_RATE_TABLE *rt = sc->sc_currates; 473 uint8_t rix1, s1code, rix2, s2code, rix3, s3code; 474 475 /* XXX precalculate short preamble tables */ 476 rix1 = sched->r1; 477 s1code = rt->info[rix1].rateCode 478 | (shortPreamble ? rt->info[rix1].shortPreamble : 0); 479 rix2 = sched->r2; 480 s2code = rt->info[rix2].rateCode 481 | (shortPreamble ? rt->info[rix2].shortPreamble : 0); 482 rix3 = sched->r3; 483 s3code = rt->info[rix3].rateCode 484 | (shortPreamble ? rt->info[rix3].shortPreamble : 0); 485 ath_hal_setupxtxdesc(sc->sc_ah, ds, 486 s1code, sched->t1, /* series 1 */ 487 s2code, sched->t2, /* series 2 */ 488 s3code, sched->t3); /* series 3 */ 489 } 490 491 static void 492 update_stats(struct ath_softc *sc, struct ath_node *an, 493 int frame_size, 494 int rix0, int tries0, 495 int rix1, int tries1, 496 int rix2, int tries2, 497 int rix3, int tries3, 498 int short_tries, int tries, int status) 499 { 500 struct sample_node *sn = ATH_NODE_SAMPLE(an); 501 struct sample_softc *ssc = ATH_SOFTC_SAMPLE(sc); 502 const int size_bin = size_to_bin(frame_size); 503 const int size = bin_to_size(size_bin); 504 int tt, tries_so_far; 505 int is_ht40 = (an->an_node.ni_chw == 40); 506 507 if (!IS_RATE_DEFINED(sn, rix0)) 508 return; 509 tt = calc_usecs_unicast_packet(sc, size, rix0, short_tries, 510 MIN(tries0, tries) - 1, is_ht40); 511 tries_so_far = tries0; 512 513 if (tries1 && tries_so_far < tries) { 514 if (!IS_RATE_DEFINED(sn, rix1)) 515 return; 516 tt += calc_usecs_unicast_packet(sc, size, rix1, short_tries, 517 MIN(tries1 + tries_so_far, tries) - tries_so_far - 1, is_ht40); 518 tries_so_far += tries1; 519 } 520 521 if (tries2 && tries_so_far < tries) { 522 if (!IS_RATE_DEFINED(sn, rix2)) 523 return; 524 tt += calc_usecs_unicast_packet(sc, size, rix2, short_tries, 525 MIN(tries2 + tries_so_far, tries) - tries_so_far - 1, is_ht40); 526 tries_so_far += tries2; 527 } 528 529 if (tries3 && tries_so_far < tries) { 530 if (!IS_RATE_DEFINED(sn, rix3)) 531 return; 532 tt += calc_usecs_unicast_packet(sc, size, rix3, short_tries, 533 MIN(tries3 + tries_so_far, tries) - tries_so_far - 1, is_ht40); 534 } 535 536 if (sn->stats[size_bin][rix0].total_packets < ssc->smoothing_minpackets) { 537 /* just average the first few packets */ 538 int avg_tx = sn->stats[size_bin][rix0].average_tx_time; 539 int packets = sn->stats[size_bin][rix0].total_packets; 540 sn->stats[size_bin][rix0].average_tx_time = (tt+(avg_tx*packets))/(packets+1); 541 } else { 542 /* use a ewma */ 543 sn->stats[size_bin][rix0].average_tx_time = 544 ((sn->stats[size_bin][rix0].average_tx_time * ssc->smoothing_rate) + 545 (tt * (100 - ssc->smoothing_rate))) / 100; 546 } 547 548 if (status != 0) { 549 int y; 550 sn->stats[size_bin][rix0].successive_failures++; 551 for (y = size_bin+1; y < NUM_PACKET_SIZE_BINS; y++) { 552 /* 553 * Also say larger packets failed since we 554 * assume if a small packet fails at a 555 * bit-rate then a larger one will also. 556 */ 557 sn->stats[y][rix0].successive_failures++; 558 sn->stats[y][rix0].last_tx = ticks; 559 sn->stats[y][rix0].tries += tries; 560 sn->stats[y][rix0].total_packets++; 561 } 562 } else { 563 sn->stats[size_bin][rix0].packets_acked++; 564 sn->stats[size_bin][rix0].successive_failures = 0; 565 } 566 sn->stats[size_bin][rix0].tries += tries; 567 sn->stats[size_bin][rix0].last_tx = ticks; 568 sn->stats[size_bin][rix0].total_packets++; 569 570 if (rix0 == sn->current_sample_rix[size_bin]) { 571 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 572 &an->an_node, 573 "%s: size %d %s sample rate %d tries (%d/%d) tt %d avg_tt (%d/%d)", 574 __func__, 575 size, 576 status ? "FAIL" : "OK", 577 rix0, short_tries, tries, tt, 578 sn->stats[size_bin][rix0].average_tx_time, 579 sn->stats[size_bin][rix0].perfect_tx_time); 580 sn->sample_tt[size_bin] = tt; 581 sn->current_sample_rix[size_bin] = -1; 582 } 583 } 584 585 static void 586 badrate(struct ifnet *ifp, int series, int hwrate, int tries, int status) 587 { 588 if_printf(ifp, "bad series%d hwrate 0x%x, tries %u ts_status 0x%x\n", 589 series, hwrate, tries, status); 590 } 591 592 void 593 ath_rate_tx_complete(struct ath_softc *sc, struct ath_node *an, 594 const struct ath_buf *bf) 595 { 596 struct ifnet *ifp = sc->sc_ifp; 597 struct ieee80211com *ic = ifp->if_l2com; 598 struct sample_node *sn = ATH_NODE_SAMPLE(an); 599 const struct ath_tx_status *ts = &bf->bf_status.ds_txstat; 600 const struct ath_desc *ds0 = &bf->bf_desc[0]; 601 int final_rix, short_tries, long_tries, frame_size; 602 const HAL_RATE_TABLE *rt = sc->sc_currates; 603 int mrr; 604 605 final_rix = rt->rateCodeToIndex[ts->ts_rate]; 606 short_tries = ts->ts_shortretry; 607 long_tries = ts->ts_longretry + 1; 608 frame_size = ds0->ds_ctl0 & 0x0fff; /* low-order 12 bits of ds_ctl0 */ 609 if (frame_size == 0) /* NB: should not happen */ 610 frame_size = 1500; 611 612 if (sn->ratemask == 0) { 613 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 614 &an->an_node, 615 "%s: size %d %s rate/try %d/%d no rates yet", 616 __func__, 617 bin_to_size(size_to_bin(frame_size)), 618 ts->ts_status ? "FAIL" : "OK", 619 short_tries, long_tries); 620 return; 621 } 622 mrr = sc->sc_mrretry && !(ic->ic_flags & IEEE80211_F_USEPROT); 623 if (!mrr || ts->ts_finaltsi == 0) { 624 if (!IS_RATE_DEFINED(sn, final_rix)) { 625 badrate(ifp, 0, ts->ts_rate, long_tries, ts->ts_status); 626 return; 627 } 628 /* 629 * Only one rate was used; optimize work. 630 */ 631 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 632 &an->an_node, "%s: size %d (%d bytes) %s rate/try %d %s/%d/%d", 633 __func__, 634 bin_to_size(size_to_bin(frame_size)), 635 frame_size, 636 ts->ts_status ? "FAIL" : "OK", 637 dot11rate(rt, final_rix), dot11rate_label(rt, final_rix), short_tries, long_tries); 638 update_stats(sc, an, frame_size, 639 final_rix, long_tries, 640 0, 0, 641 0, 0, 642 0, 0, 643 short_tries, long_tries, ts->ts_status); 644 } else { 645 int hwrates[4], tries[4], rix[4]; 646 int finalTSIdx = ts->ts_finaltsi; 647 int i; 648 649 /* 650 * Process intermediate rates that failed. 651 */ 652 ath_hal_gettxcompletionrates(sc->sc_ah, ds0, hwrates, tries); 653 654 for (i = 0; i < 4; i++) { 655 rix[i] = rt->rateCodeToIndex[hwrates[i]]; 656 } 657 658 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 659 &an->an_node, 660 "%s: size %d (%d bytes) finaltsidx %d tries %d %s rate/try [%d %s/%d %d %s/%d %d %s/%d %d %s/%d]", 661 __func__, 662 bin_to_size(size_to_bin(frame_size)), 663 frame_size, 664 finalTSIdx, 665 long_tries, 666 ts->ts_status ? "FAIL" : "OK", 667 dot11rate(rt, rix[0]), dot11rate_label(rt, rix[0]), tries[0], 668 dot11rate(rt, rix[1]), dot11rate_label(rt, rix[1]), tries[1], 669 dot11rate(rt, rix[2]), dot11rate_label(rt, rix[2]), tries[2], 670 dot11rate(rt, rix[3]), dot11rate_label(rt, rix[3]), tries[3]); 671 672 for (i = 0; i < 4; i++) { 673 if (tries[i] && !IS_RATE_DEFINED(sn, rix[i])) 674 badrate(ifp, 0, hwrates[i], tries[i], ts->ts_status); 675 } 676 677 /* 678 * NB: series > 0 are not penalized for failure 679 * based on the try counts under the assumption 680 * that losses are often bursty and since we 681 * sample higher rates 1 try at a time doing so 682 * may unfairly penalize them. 683 */ 684 if (tries[0]) { 685 update_stats(sc, an, frame_size, 686 rix[0], tries[0], 687 rix[1], tries[1], 688 rix[2], tries[2], 689 rix[3], tries[3], 690 short_tries, long_tries, 691 long_tries > tries[0]); 692 long_tries -= tries[0]; 693 } 694 695 if (tries[1] && finalTSIdx > 0) { 696 update_stats(sc, an, frame_size, 697 rix[1], tries[1], 698 rix[2], tries[2], 699 rix[3], tries[3], 700 0, 0, 701 short_tries, long_tries, 702 ts->ts_status); 703 long_tries -= tries[1]; 704 } 705 706 if (tries[2] && finalTSIdx > 1) { 707 update_stats(sc, an, frame_size, 708 rix[2], tries[2], 709 rix[3], tries[3], 710 0, 0, 711 0, 0, 712 short_tries, long_tries, 713 ts->ts_status); 714 long_tries -= tries[2]; 715 } 716 717 if (tries[3] && finalTSIdx > 2) { 718 update_stats(sc, an, frame_size, 719 rix[3], tries[3], 720 0, 0, 721 0, 0, 722 0, 0, 723 short_tries, long_tries, 724 ts->ts_status); 725 } 726 } 727 } 728 729 void 730 ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew) 731 { 732 if (isnew) 733 ath_rate_ctl_reset(sc, &an->an_node); 734 } 735 736 static const struct txschedule *mrr_schedules[IEEE80211_MODE_MAX+2] = { 737 NULL, /* IEEE80211_MODE_AUTO */ 738 series_11a, /* IEEE80211_MODE_11A */ 739 series_11g, /* IEEE80211_MODE_11B */ 740 series_11g, /* IEEE80211_MODE_11G */ 741 NULL, /* IEEE80211_MODE_FH */ 742 series_11a, /* IEEE80211_MODE_TURBO_A */ 743 series_11g, /* IEEE80211_MODE_TURBO_G */ 744 series_11a, /* IEEE80211_MODE_STURBO_A */ 745 series_11na, /* IEEE80211_MODE_11NA */ 746 series_11ng, /* IEEE80211_MODE_11NG */ 747 series_half, /* IEEE80211_MODE_HALF */ 748 series_quarter, /* IEEE80211_MODE_QUARTER */ 749 }; 750 751 /* 752 * Initialize the tables for a node. 753 */ 754 static void 755 ath_rate_ctl_reset(struct ath_softc *sc, struct ieee80211_node *ni) 756 { 757 #define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL) 758 #define DOT11RATE(_ix) (rt->info[(_ix)].dot11Rate & IEEE80211_RATE_VAL) 759 #define MCS(_ix) (ni->ni_htrates.rs_rates[_ix] | IEEE80211_RATE_MCS) 760 struct ath_node *an = ATH_NODE(ni); 761 struct sample_node *sn = ATH_NODE_SAMPLE(an); 762 const HAL_RATE_TABLE *rt = sc->sc_currates; 763 int x, y, rix; 764 765 KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode)); 766 767 KASSERT(sc->sc_curmode < IEEE80211_MODE_MAX+2, 768 ("curmode %u", sc->sc_curmode)); 769 sn->sched = mrr_schedules[sc->sc_curmode]; 770 KASSERT(sn->sched != NULL, 771 ("no mrr schedule for mode %u", sc->sc_curmode)); 772 773 sn->static_rix = -1; 774 ath_rate_update_static_rix(sc, ni); 775 776 /* 777 * Construct a bitmask of usable rates. This has all 778 * negotiated rates minus those marked by the hal as 779 * to be ignored for doing rate control. 780 */ 781 sn->ratemask = 0; 782 /* MCS rates */ 783 if (ni->ni_flags & IEEE80211_NODE_HT) { 784 for (x = 0; x < ni->ni_htrates.rs_nrates; x++) { 785 rix = sc->sc_rixmap[MCS(x)]; 786 if (rix == 0xff) 787 continue; 788 /* skip rates marked broken by hal */ 789 if (!rt->info[rix].valid) 790 continue; 791 KASSERT(rix < SAMPLE_MAXRATES, 792 ("mcs %u has rix %d", MCS(x), rix)); 793 sn->ratemask |= 1<<rix; 794 } 795 } 796 797 /* Legacy rates */ 798 for (x = 0; x < ni->ni_rates.rs_nrates; x++) { 799 rix = sc->sc_rixmap[RATE(x)]; 800 if (rix == 0xff) 801 continue; 802 /* skip rates marked broken by hal */ 803 if (!rt->info[rix].valid) 804 continue; 805 KASSERT(rix < SAMPLE_MAXRATES, 806 ("rate %u has rix %d", RATE(x), rix)); 807 sn->ratemask |= 1<<rix; 808 } 809 #ifdef IEEE80211_DEBUG 810 if (ieee80211_msg(ni->ni_vap, IEEE80211_MSG_RATECTL)) { 811 uint32_t mask; 812 813 ieee80211_note(ni->ni_vap, "[%6D] %s: size 1600 rate/tt", 814 ni->ni_macaddr, ":", __func__); 815 for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) { 816 if ((mask & 1) == 0) 817 continue; 818 printf(" %d %s/%d", dot11rate(rt, rix), dot11rate_label(rt, rix), 819 calc_usecs_unicast_packet(sc, 1600, rix, 0,0, 820 (ni->ni_chw == 40))); 821 } 822 printf("\n"); 823 } 824 #endif 825 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) { 826 int size = bin_to_size(y); 827 uint32_t mask; 828 829 sn->packets_sent[y] = 0; 830 sn->current_sample_rix[y] = -1; 831 sn->last_sample_rix[y] = 0; 832 /* XXX start with first valid rate */ 833 sn->current_rix[y] = ffs(sn->ratemask)-1; 834 835 /* 836 * Initialize the statistics buckets; these are 837 * indexed by the rate code index. 838 */ 839 for (rix = 0, mask = sn->ratemask; mask != 0; rix++, mask >>= 1) { 840 if ((mask & 1) == 0) /* not a valid rate */ 841 continue; 842 sn->stats[y][rix].successive_failures = 0; 843 sn->stats[y][rix].tries = 0; 844 sn->stats[y][rix].total_packets = 0; 845 sn->stats[y][rix].packets_acked = 0; 846 sn->stats[y][rix].last_tx = 0; 847 848 sn->stats[y][rix].perfect_tx_time = 849 calc_usecs_unicast_packet(sc, size, rix, 0, 0, 850 (ni->ni_chw == 40)); 851 sn->stats[y][rix].average_tx_time = 852 sn->stats[y][rix].perfect_tx_time; 853 } 854 } 855 #if 0 856 /* XXX 0, num_rates-1 are wrong */ 857 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, 858 "%s: %d rates %d%sMbps (%dus)- %d%sMbps (%dus)", __func__, 859 sn->num_rates, 860 DOT11RATE(0)/2, DOT11RATE(0) % 1 ? ".5" : "", 861 sn->stats[1][0].perfect_tx_time, 862 DOT11RATE(sn->num_rates-1)/2, DOT11RATE(sn->num_rates-1) % 1 ? ".5" : "", 863 sn->stats[1][sn->num_rates-1].perfect_tx_time 864 ); 865 #endif 866 /* set the visible bit-rate */ 867 if (sn->static_rix != -1) 868 ni->ni_txrate = DOT11RATE(sn->static_rix); 869 else 870 ni->ni_txrate = RATE(0); 871 #undef RATE 872 #undef DOT11RATE 873 } 874 875 static void 876 sample_stats(void *arg, struct ieee80211_node *ni) 877 { 878 struct ath_softc *sc = arg; 879 const HAL_RATE_TABLE *rt = sc->sc_currates; 880 struct sample_node *sn = ATH_NODE_SAMPLE(ATH_NODE(ni)); 881 uint32_t mask; 882 int rix, y; 883 884 printf("\n[%s] refcnt %d static_rix %d ratemask 0x%x\n", 885 ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni), 886 sn->static_rix, sn->ratemask); 887 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) { 888 printf("[%4u] cur rix %d (%d %s) since switch: packets %d ticks %u\n", 889 bin_to_size(y), sn->current_rix[y], 890 dot11rate(rt, sn->current_rix[y]), 891 dot11rate_label(rt, sn->current_rix[y]), 892 sn->packets_since_switch[y], sn->ticks_since_switch[y]); 893 printf("[%4u] last sample %d cur sample %d packets sent %d\n", 894 bin_to_size(y), sn->last_sample_rix[y], 895 sn->current_sample_rix[y], sn->packets_sent[y]); 896 printf("[%4u] packets since sample %d sample tt %u\n", 897 bin_to_size(y), sn->packets_since_sample[y], 898 sn->sample_tt[y]); 899 } 900 for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) { 901 if ((mask & 1) == 0) 902 continue; 903 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) { 904 if (sn->stats[y][rix].total_packets == 0) 905 continue; 906 printf("[%2u %s:%4u] %8d:%-8d (%3d%%) T %8d F %4d avg %5u last %u\n", 907 dot11rate(rt, rix), dot11rate_label(rt, rix), 908 bin_to_size(y), 909 sn->stats[y][rix].total_packets, 910 sn->stats[y][rix].packets_acked, 911 (100*sn->stats[y][rix].packets_acked)/sn->stats[y][rix].total_packets, 912 sn->stats[y][rix].tries, 913 sn->stats[y][rix].successive_failures, 914 sn->stats[y][rix].average_tx_time, 915 ticks - sn->stats[y][rix].last_tx); 916 } 917 } 918 } 919 920 static int 921 ath_rate_sysctl_stats(SYSCTL_HANDLER_ARGS) 922 { 923 struct ath_softc *sc = arg1; 924 struct ifnet *ifp = sc->sc_ifp; 925 struct ieee80211com *ic = ifp->if_l2com; 926 int error, v; 927 928 v = 0; 929 error = sysctl_handle_int(oidp, &v, 0, req); 930 if (error || !req->newptr) 931 return error; 932 ieee80211_iterate_nodes(&ic->ic_sta, sample_stats, sc); 933 return 0; 934 } 935 936 static int 937 ath_rate_sysctl_smoothing_rate(SYSCTL_HANDLER_ARGS) 938 { 939 struct sample_softc *ssc = arg1; 940 int rate, error; 941 942 rate = ssc->smoothing_rate; 943 error = sysctl_handle_int(oidp, &rate, 0, req); 944 if (error || !req->newptr) 945 return error; 946 if (!(0 <= rate && rate < 100)) 947 return EINVAL; 948 ssc->smoothing_rate = rate; 949 ssc->smoothing_minpackets = 100 / (100 - rate); 950 return 0; 951 } 952 953 static int 954 ath_rate_sysctl_sample_rate(SYSCTL_HANDLER_ARGS) 955 { 956 struct sample_softc *ssc = arg1; 957 int rate, error; 958 959 rate = ssc->sample_rate; 960 error = sysctl_handle_int(oidp, &rate, 0, req); 961 if (error || !req->newptr) 962 return error; 963 if (!(2 <= rate && rate <= 100)) 964 return EINVAL; 965 ssc->sample_rate = rate; 966 return 0; 967 } 968 969 static void 970 ath_rate_sysctlattach(struct ath_softc *sc, struct sample_softc *ssc) 971 { 972 struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev); 973 struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev); 974 975 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 976 "smoothing_rate", CTLTYPE_INT | CTLFLAG_RW, ssc, 0, 977 ath_rate_sysctl_smoothing_rate, "I", 978 "sample: smoothing rate for avg tx time (%%)"); 979 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 980 "sample_rate", CTLTYPE_INT | CTLFLAG_RW, ssc, 0, 981 ath_rate_sysctl_sample_rate, "I", 982 "sample: percent air time devoted to sampling new rates (%%)"); 983 /* XXX max_successive_failures, stale_failure_timeout, min_switch */ 984 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 985 "sample_stats", CTLTYPE_INT | CTLFLAG_RW, sc, 0, 986 ath_rate_sysctl_stats, "I", "sample: print statistics"); 987 } 988 989 struct ath_ratectrl * 990 ath_rate_attach(struct ath_softc *sc) 991 { 992 struct sample_softc *ssc; 993 994 ssc = malloc(sizeof(struct sample_softc), M_DEVBUF, M_NOWAIT|M_ZERO); 995 if (ssc == NULL) 996 return NULL; 997 ssc->arc.arc_space = sizeof(struct sample_node); 998 ssc->smoothing_rate = 95; /* ewma percentage ([0..99]) */ 999 ssc->smoothing_minpackets = 100 / (100 - ssc->smoothing_rate); 1000 ssc->sample_rate = 10; /* %time to try diff tx rates */ 1001 ssc->max_successive_failures = 3; /* threshold for rate sampling*/ 1002 ssc->stale_failure_timeout = 10 * hz; /* 10 seconds */ 1003 ssc->min_switch = hz; /* 1 second */ 1004 ath_rate_sysctlattach(sc, ssc); 1005 return &ssc->arc; 1006 } 1007 1008 void 1009 ath_rate_detach(struct ath_ratectrl *arc) 1010 { 1011 struct sample_softc *ssc = (struct sample_softc *) arc; 1012 1013 free(ssc, M_DEVBUF); 1014 } 1015