amrr.c revision 171613
1/*- 2 * Copyright (c) 2004 INRIA 3 * Copyright (c) 2002-2005 Sam Leffler, Errno Consulting 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer, 11 * without modification. 12 * 2. Redistributions in binary form must reproduce at minimum a disclaimer 13 * similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any 14 * redistribution must be conditioned upon including a substantially 15 * similar Disclaimer requirement for further binary redistribution. 16 * 3. Neither the names of the above-listed copyright holders nor the names 17 * of any contributors may be used to endorse or promote products derived 18 * from this software without specific prior written permission. 19 * 20 * Alternatively, this software may be distributed under the terms of the 21 * GNU General Public License ("GPL") version 2 as published by the Free 22 * Software Foundation. 23 * 24 * NO WARRANTY 25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 26 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 27 * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY 28 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 29 * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, 30 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER 33 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 35 * THE POSSIBILITY OF SUCH DAMAGES. 36 * 37 */ 38 39#include <sys/cdefs.h> 40__FBSDID("$FreeBSD: head/sys/dev/ath/ath_rate/amrr/amrr.c 171613 2007-07-27 11:59:57Z rwatson $"); 41 42/* 43 * AMRR rate control. See: 44 * http://www-sop.inria.fr/rapports/sophia/RR-5208.html 45 * "IEEE 802.11 Rate Adaptation: A Practical Approach" by 46 * Mathieu Lacage, Hossein Manshaei, Thierry Turletti 47 */ 48#include "opt_inet.h" 49 50#include <sys/param.h> 51#include <sys/systm.h> 52#include <sys/sysctl.h> 53#include <sys/module.h> 54#include <sys/kernel.h> 55#include <sys/lock.h> 56#include <sys/mutex.h> 57#include <sys/errno.h> 58 59#include <machine/bus.h> 60#include <machine/resource.h> 61#include <sys/bus.h> 62 63#include <sys/socket.h> 64 65#include <net/if.h> 66#include <net/if_media.h> 67#include <net/if_arp.h> 68#include <net/ethernet.h> /* XXX for ether_sprintf */ 69 70#include <net80211/ieee80211_var.h> 71 72#include <net/bpf.h> 73 74#ifdef INET 75#include <netinet/in.h> 76#include <netinet/if_ether.h> 77#endif 78 79#include <dev/ath/if_athvar.h> 80#include <dev/ath/ath_rate/amrr/amrr.h> 81#include <contrib/dev/ath/ah_desc.h> 82 83#define AMRR_DEBUG 84#ifdef AMRR_DEBUG 85#define DPRINTF(sc, _fmt, ...) do { \ 86 if (sc->sc_debug & 0x10) \ 87 printf(_fmt, __VA_ARGS__); \ 88} while (0) 89#else 90#define DPRINTF(sc, _fmt, ...) 91#endif 92 93static int ath_rateinterval = 1000; /* rate ctl interval (ms) */ 94static int ath_rate_max_success_threshold = 10; 95static int ath_rate_min_success_threshold = 1; 96 97static void ath_ratectl(void *); 98static void ath_rate_update(struct ath_softc *, struct ieee80211_node *, 99 int rate); 100static void ath_rate_ctl_start(struct ath_softc *, struct ieee80211_node *); 101static void ath_rate_ctl(void *, struct ieee80211_node *); 102 103void 104ath_rate_node_init(struct ath_softc *sc, struct ath_node *an) 105{ 106 /* NB: assumed to be zero'd by caller */ 107 ath_rate_update(sc, &an->an_node, 0); 108} 109 110void 111ath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an) 112{ 113} 114 115void 116ath_rate_findrate(struct ath_softc *sc, struct ath_node *an, 117 int shortPreamble, size_t frameLen, 118 u_int8_t *rix, int *try0, u_int8_t *txrate) 119{ 120 struct amrr_node *amn = ATH_NODE_AMRR(an); 121 122 *rix = amn->amn_tx_rix0; 123 *try0 = amn->amn_tx_try0; 124 if (shortPreamble) 125 *txrate = amn->amn_tx_rate0sp; 126 else 127 *txrate = amn->amn_tx_rate0; 128} 129 130void 131ath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an, 132 struct ath_desc *ds, int shortPreamble, u_int8_t rix) 133{ 134 struct amrr_node *amn = ATH_NODE_AMRR(an); 135 136 ath_hal_setupxtxdesc(sc->sc_ah, ds 137 , amn->amn_tx_rate1sp, amn->amn_tx_try1 /* series 1 */ 138 , amn->amn_tx_rate2sp, amn->amn_tx_try2 /* series 2 */ 139 , amn->amn_tx_rate3sp, amn->amn_tx_try3 /* series 3 */ 140 ); 141} 142 143void 144ath_rate_tx_complete(struct ath_softc *sc, struct ath_node *an, 145 const struct ath_buf *bf) 146{ 147 struct amrr_node *amn = ATH_NODE_AMRR(an); 148 const struct ath_tx_status *ts = &bf->bf_status.ds_txstat; 149 int sr = ts->ts_shortretry; 150 int lr = ts->ts_longretry; 151 int retry_count = sr + lr; 152 153 amn->amn_tx_try0_cnt++; 154 if (retry_count == 1) { 155 amn->amn_tx_try1_cnt++; 156 } else if (retry_count == 2) { 157 amn->amn_tx_try1_cnt++; 158 amn->amn_tx_try2_cnt++; 159 } else if (retry_count == 3) { 160 amn->amn_tx_try1_cnt++; 161 amn->amn_tx_try2_cnt++; 162 amn->amn_tx_try3_cnt++; 163 } else if (retry_count > 3) { 164 amn->amn_tx_try1_cnt++; 165 amn->amn_tx_try2_cnt++; 166 amn->amn_tx_try3_cnt++; 167 amn->amn_tx_failure_cnt++; 168 } 169} 170 171void 172ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew) 173{ 174 if (isnew) 175 ath_rate_ctl_start(sc, &an->an_node); 176} 177 178static void 179node_reset (struct amrr_node *amn) 180{ 181 amn->amn_tx_try0_cnt = 0; 182 amn->amn_tx_try1_cnt = 0; 183 amn->amn_tx_try2_cnt = 0; 184 amn->amn_tx_try3_cnt = 0; 185 amn->amn_tx_failure_cnt = 0; 186 amn->amn_success = 0; 187 amn->amn_recovery = 0; 188 amn->amn_success_threshold = ath_rate_min_success_threshold; 189} 190 191 192/** 193 * The code below assumes that we are dealing with hardware multi rate retry 194 * I have no idea what will happen if you try to use this module with another 195 * type of hardware. Your machine might catch fire or it might work with 196 * horrible performance... 197 */ 198static void 199ath_rate_update(struct ath_softc *sc, struct ieee80211_node *ni, int rate) 200{ 201 struct ath_node *an = ATH_NODE(ni); 202 struct amrr_node *amn = ATH_NODE_AMRR(an); 203 const HAL_RATE_TABLE *rt = sc->sc_currates; 204 u_int8_t rix; 205 206 KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode)); 207 208 DPRINTF(sc, "%s: set xmit rate for %s to %dM\n", 209 __func__, ether_sprintf(ni->ni_macaddr), 210 ni->ni_rates.rs_nrates > 0 ? 211 (ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL) / 2 : 0); 212 213 ni->ni_txrate = rate; 214 /* 215 * Before associating a node has no rate set setup 216 * so we can't calculate any transmit codes to use. 217 * This is ok since we should never be sending anything 218 * but management frames and those always go at the 219 * lowest hardware rate. 220 */ 221 if (ni->ni_rates.rs_nrates > 0) { 222 amn->amn_tx_rix0 = sc->sc_rixmap[ 223 ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL]; 224 amn->amn_tx_rate0 = rt->info[amn->amn_tx_rix0].rateCode; 225 amn->amn_tx_rate0sp = amn->amn_tx_rate0 | 226 rt->info[amn->amn_tx_rix0].shortPreamble; 227 if (sc->sc_mrretry) { 228 amn->amn_tx_try0 = 1; 229 amn->amn_tx_try1 = 1; 230 amn->amn_tx_try2 = 1; 231 amn->amn_tx_try3 = 1; 232 if (--rate >= 0) { 233 rix = sc->sc_rixmap[ 234 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; 235 amn->amn_tx_rate1 = rt->info[rix].rateCode; 236 amn->amn_tx_rate1sp = amn->amn_tx_rate1 | 237 rt->info[rix].shortPreamble; 238 } else { 239 amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0; 240 } 241 if (--rate >= 0) { 242 rix = sc->sc_rixmap[ 243 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; 244 amn->amn_tx_rate2 = rt->info[rix].rateCode; 245 amn->amn_tx_rate2sp = amn->amn_tx_rate2 | 246 rt->info[rix].shortPreamble; 247 } else { 248 amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0; 249 } 250 if (rate > 0) { 251 /* NB: only do this if we didn't already do it above */ 252 amn->amn_tx_rate3 = rt->info[0].rateCode; 253 amn->amn_tx_rate3sp = 254 amn->amn_tx_rate3 | rt->info[0].shortPreamble; 255 } else { 256 amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0; 257 } 258 } else { 259 amn->amn_tx_try0 = ATH_TXMAXTRY; 260 /* theorically, these statements are useless because 261 * the code which uses them tests for an_tx_try0 == ATH_TXMAXTRY 262 */ 263 amn->amn_tx_try1 = 0; 264 amn->amn_tx_try2 = 0; 265 amn->amn_tx_try3 = 0; 266 amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0; 267 amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0; 268 amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0; 269 } 270 } 271 node_reset (amn); 272} 273 274/* 275 * Set the starting transmit rate for a node. 276 */ 277static void 278ath_rate_ctl_start(struct ath_softc *sc, struct ieee80211_node *ni) 279{ 280#define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL) 281 struct ieee80211com *ic = &sc->sc_ic; 282 int srate; 283 284 KASSERT(ni->ni_rates.rs_nrates > 0, ("no rates")); 285 if (ic->ic_fixed_rate == IEEE80211_FIXED_RATE_NONE) { 286 /* 287 * No fixed rate is requested. For 11b start with 288 * the highest negotiated rate; otherwise, for 11g 289 * and 11a, we start "in the middle" at 24Mb or 36Mb. 290 */ 291 srate = ni->ni_rates.rs_nrates - 1; 292 if (sc->sc_curmode != IEEE80211_MODE_11B) { 293 /* 294 * Scan the negotiated rate set to find the 295 * closest rate. 296 */ 297 /* NB: the rate set is assumed sorted */ 298 for (; srate >= 0 && RATE(srate) > 72; srate--) 299 ; 300 } 301 } else { 302 /* 303 * A fixed rate is to be used; ic_fixed_rate is the 304 * IEEE code for this rate (sans basic bit). Convert this 305 * to the index into the negotiated rate set for 306 * the node. We know the rate is there because the 307 * rate set is checked when the station associates. 308 */ 309 /* NB: the rate set is assumed sorted */ 310 srate = ni->ni_rates.rs_nrates - 1; 311 for (; srate >= 0 && RATE(srate) != ic->ic_fixed_rate; srate--) 312 ; 313 } 314 /* 315 * The selected rate may not be available due to races 316 * and mode settings. Also orphaned nodes created in 317 * adhoc mode may not have any rate set so this lookup 318 * can fail. This is not fatal. 319 */ 320 ath_rate_update(sc, ni, srate < 0 ? 0 : srate); 321#undef RATE 322} 323 324static void 325ath_rate_cb(void *arg, struct ieee80211_node *ni) 326{ 327 struct ath_softc *sc = arg; 328 329 ath_rate_update(sc, ni, 0); 330} 331 332/* 333 * Reset the rate control state for each 802.11 state transition. 334 */ 335void 336ath_rate_newstate(struct ath_softc *sc, enum ieee80211_state state) 337{ 338 struct amrr_softc *asc = (struct amrr_softc *) sc->sc_rc; 339 struct ieee80211com *ic = &sc->sc_ic; 340 struct ieee80211_node *ni; 341 342 if (state == IEEE80211_S_INIT) { 343 callout_stop(&asc->timer); 344 return; 345 } 346 if (ic->ic_opmode == IEEE80211_M_STA) { 347 /* 348 * Reset local xmit state; this is really only 349 * meaningful when operating in station mode. 350 */ 351 ni = ic->ic_bss; 352 if (state == IEEE80211_S_RUN) { 353 ath_rate_ctl_start(sc, ni); 354 } else { 355 ath_rate_update(sc, ni, 0); 356 } 357 } else { 358 /* 359 * When operating as a station the node table holds 360 * the AP's that were discovered during scanning. 361 * For any other operating mode we want to reset the 362 * tx rate state of each node. 363 */ 364 ieee80211_iterate_nodes(&ic->ic_sta, ath_rate_cb, sc); 365 ath_rate_update(sc, ic->ic_bss, 0); 366 } 367 if (ic->ic_fixed_rate == IEEE80211_FIXED_RATE_NONE && 368 state == IEEE80211_S_RUN) { 369 int interval; 370 /* 371 * Start the background rate control thread if we 372 * are not configured to use a fixed xmit rate. 373 */ 374 interval = ath_rateinterval; 375 if (ic->ic_opmode == IEEE80211_M_STA) 376 interval /= 2; 377 callout_reset(&asc->timer, (interval * hz) / 1000, 378 ath_ratectl, sc->sc_ifp); 379 } 380} 381 382/* 383 * Examine and potentially adjust the transmit rate. 384 */ 385static void 386ath_rate_ctl(void *arg, struct ieee80211_node *ni) 387{ 388 struct ath_softc *sc = arg; 389 struct amrr_node *amn = ATH_NODE_AMRR(ATH_NODE (ni)); 390 int old_rate; 391 392#define is_success(amn) \ 393(amn->amn_tx_try1_cnt < (amn->amn_tx_try0_cnt/10)) 394#define is_enough(amn) \ 395(amn->amn_tx_try0_cnt > 10) 396#define is_failure(amn) \ 397(amn->amn_tx_try1_cnt > (amn->amn_tx_try0_cnt/3)) 398#define is_max_rate(ni) \ 399((ni->ni_txrate + 1) >= ni->ni_rates.rs_nrates) 400#define is_min_rate(ni) \ 401(ni->ni_txrate == 0) 402 403 old_rate = ni->ni_txrate; 404 405 DPRINTF (sc, "cnt0: %d cnt1: %d cnt2: %d cnt3: %d -- threshold: %d\n", 406 amn->amn_tx_try0_cnt, 407 amn->amn_tx_try1_cnt, 408 amn->amn_tx_try2_cnt, 409 amn->amn_tx_try3_cnt, 410 amn->amn_success_threshold); 411 if (is_success (amn) && is_enough (amn)) { 412 amn->amn_success++; 413 if (amn->amn_success == amn->amn_success_threshold && 414 !is_max_rate (ni)) { 415 amn->amn_recovery = 1; 416 amn->amn_success = 0; 417 ni->ni_txrate++; 418 DPRINTF (sc, "increase rate to %d\n", ni->ni_txrate); 419 } else { 420 amn->amn_recovery = 0; 421 } 422 } else if (is_failure (amn)) { 423 amn->amn_success = 0; 424 if (!is_min_rate (ni)) { 425 if (amn->amn_recovery) { 426 /* recovery failure. */ 427 amn->amn_success_threshold *= 2; 428 amn->amn_success_threshold = min (amn->amn_success_threshold, 429 (u_int)ath_rate_max_success_threshold); 430 DPRINTF (sc, "decrease rate recovery thr: %d\n", amn->amn_success_threshold); 431 } else { 432 /* simple failure. */ 433 amn->amn_success_threshold = ath_rate_min_success_threshold; 434 DPRINTF (sc, "decrease rate normal thr: %d\n", amn->amn_success_threshold); 435 } 436 amn->amn_recovery = 0; 437 ni->ni_txrate--; 438 } else { 439 amn->amn_recovery = 0; 440 } 441 442 } 443 if (is_enough (amn) || old_rate != ni->ni_txrate) { 444 /* reset counters. */ 445 amn->amn_tx_try0_cnt = 0; 446 amn->amn_tx_try1_cnt = 0; 447 amn->amn_tx_try2_cnt = 0; 448 amn->amn_tx_try3_cnt = 0; 449 amn->amn_tx_failure_cnt = 0; 450 } 451 if (old_rate != ni->ni_txrate) { 452 ath_rate_update(sc, ni, ni->ni_txrate); 453 } 454} 455 456static void 457ath_ratectl(void *arg) 458{ 459 struct ifnet *ifp = arg; 460 struct ath_softc *sc = ifp->if_softc; 461 struct amrr_softc *asc = (struct amrr_softc *) sc->sc_rc; 462 struct ieee80211com *ic = &sc->sc_ic; 463 int interval; 464 465 if (ifp->if_drv_flags & IFF_DRV_RUNNING) { 466 sc->sc_stats.ast_rate_calls++; 467 468 if (ic->ic_opmode == IEEE80211_M_STA) 469 ath_rate_ctl(sc, ic->ic_bss); /* NB: no reference */ 470 else 471 ieee80211_iterate_nodes(&ic->ic_sta, ath_rate_ctl, sc); 472 } 473 interval = ath_rateinterval; 474 if (ic->ic_opmode == IEEE80211_M_STA) 475 interval /= 2; 476 callout_reset(&asc->timer, (interval * hz) / 1000, 477 ath_ratectl, sc->sc_ifp); 478} 479 480static void 481ath_rate_sysctlattach(struct ath_softc *sc) 482{ 483 struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev); 484 struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev); 485 486 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 487 "rate_interval", CTLFLAG_RW, &ath_rateinterval, 0, 488 "rate control: operation interval (ms)"); 489 /* XXX bounds check values */ 490 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 491 "max_sucess_threshold", CTLFLAG_RW, 492 &ath_rate_max_success_threshold, 0, ""); 493 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 494 "min_sucess_threshold", CTLFLAG_RW, 495 &ath_rate_min_success_threshold, 0, ""); 496} 497 498struct ath_ratectrl * 499ath_rate_attach(struct ath_softc *sc) 500{ 501 struct amrr_softc *asc; 502 503 asc = malloc(sizeof(struct amrr_softc), M_DEVBUF, M_NOWAIT|M_ZERO); 504 if (asc == NULL) 505 return NULL; 506 asc->arc.arc_space = sizeof(struct amrr_node); 507 callout_init(&asc->timer, CALLOUT_MPSAFE); 508 ath_rate_sysctlattach(sc); 509 510 return &asc->arc; 511} 512 513void 514ath_rate_detach(struct ath_ratectrl *arc) 515{ 516 struct amrr_softc *asc = (struct amrr_softc *) arc; 517 518 callout_drain(&asc->timer); 519 free(asc, M_DEVBUF); 520} 521 522/* 523 * Module glue. 524 */ 525static int 526amrr_modevent(module_t mod, int type, void *unused) 527{ 528 switch (type) { 529 case MOD_LOAD: 530 if (bootverbose) 531 printf("ath_rate: <AMRR rate control algorithm> version 0.1\n"); 532 return 0; 533 case MOD_UNLOAD: 534 return 0; 535 } 536 return EINVAL; 537} 538 539static moduledata_t amrr_mod = { 540 "ath_rate", 541 amrr_modevent, 542 0 543}; 544DECLARE_MODULE(ath_rate, amrr_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST); 545MODULE_VERSION(ath_rate, 1); 546MODULE_DEPEND(ath_rate, wlan, 1, 1, 1); 547