1/* $NetBSD: athrate-amrr.c,v 1.10 2008/01/04 21:17:56 ad Exp $ */ 2 3/*- 4 * Copyright (c) 2004 INRIA 5 * Copyright (c) 2002-2005 Sam Leffler, Errno Consulting 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer, 13 * without modification. 14 * 2. Redistributions in binary form must reproduce at minimum a disclaimer 15 * similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any 16 * redistribution must be conditioned upon including a substantially 17 * similar Disclaimer requirement for further binary redistribution. 18 * 3. Neither the names of the above-listed copyright holders nor the names 19 * of any contributors may be used to endorse or promote products derived 20 * from this software without specific prior written permission. 21 * 22 * Alternatively, this software may be distributed under the terms of the 23 * GNU General Public License ("GPL") version 2 as published by the Free 24 * Software Foundation. 25 * 26 * NO WARRANTY 27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 29 * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY 30 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 31 * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, 32 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER 35 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 37 * THE POSSIBILITY OF SUCH DAMAGES. 38 * 39 */ 40 41#include <sys/cdefs.h> 42#ifdef __FreeBSD__ 43__FBSDID("$FreeBSD: src/sys/dev/ath/ath_rate/amrr/amrr.c,v 1.10 2005/08/09 10:19:43 rwatson Exp $"); 44#endif 45#ifdef __NetBSD__ 46__KERNEL_RCSID(0, "$NetBSD: athrate-amrr.c,v 1.10 2008/01/04 21:17:56 ad Exp $"); 47#endif 48 49/* 50 * AMRR rate control. See: 51 * http://www-sop.inria.fr/rapports/sophia/RR-5208.html 52 * "IEEE 802.11 Rate Adaptation: A Practical Approach" by 53 * Mathieu Lacage, Hossein Manshaei, Thierry Turletti 54 */ 55#include "opt_inet.h" 56 57#include <sys/param.h> 58#include <sys/systm.h> 59#include <sys/sysctl.h> 60#include <sys/kernel.h> 61#include <sys/errno.h> 62#include <sys/bus.h> 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/if_ether.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#endif 77 78#include <dev/ic/athvar.h> 79#include <dev/ic/athrate-amrr.h> 80 81#include <external/isc/atheros_hal/dist/ah.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_desc *ds, const struct ath_desc *ds0) 146{ 147 struct amrr_node *amn = ATH_NODE_AMRR(an); 148 int sr = ds->ds_txstat.ts_shortretry; 149 int lr = ds->ds_txstat.ts_longretry; 150 int retry_count = sr + lr; 151 152 amn->amn_tx_try0_cnt++; 153 if (retry_count == 1) { 154 amn->amn_tx_try1_cnt++; 155 } else if (retry_count == 2) { 156 amn->amn_tx_try1_cnt++; 157 amn->amn_tx_try2_cnt++; 158 } else if (retry_count == 3) { 159 amn->amn_tx_try1_cnt++; 160 amn->amn_tx_try2_cnt++; 161 amn->amn_tx_try3_cnt++; 162 } else if (retry_count > 3) { 163 amn->amn_tx_try1_cnt++; 164 amn->amn_tx_try2_cnt++; 165 amn->amn_tx_try3_cnt++; 166 amn->amn_tx_failure_cnt++; 167 } 168} 169 170void 171ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew) 172{ 173 if (isnew) 174 ath_rate_ctl_start(sc, &an->an_node); 175} 176 177static void 178node_reset (struct amrr_node *amn) 179{ 180 amn->amn_tx_try0_cnt = 0; 181 amn->amn_tx_try1_cnt = 0; 182 amn->amn_tx_try2_cnt = 0; 183 amn->amn_tx_try3_cnt = 0; 184 amn->amn_tx_failure_cnt = 0; 185 amn->amn_success = 0; 186 amn->amn_recovery = 0; 187 amn->amn_success_threshold = ath_rate_min_success_threshold; 188} 189 190 191/** 192 * The code below assumes that we are dealing with hardware multi rate retry 193 * I have no idea what will happen if you try to use this module with another 194 * type of hardware. Your machine might catch fire or it might work with 195 * horrible performance... 196 */ 197static void 198ath_rate_update(struct ath_softc *sc, struct ieee80211_node *ni, int rate) 199{ 200 struct ath_node *an = ATH_NODE(ni); 201 struct amrr_node *amn = ATH_NODE_AMRR(an); 202 const HAL_RATE_TABLE *rt = sc->sc_currates; 203 u_int8_t rix; 204 205 KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode)); 206 207 DPRINTF(sc, "%s: set xmit rate for %s to %dM\n", 208 __func__, ether_sprintf(ni->ni_macaddr), 209 ni->ni_rates.rs_nrates > 0 ? 210 (ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL) / 2 : 0); 211 212 ni->ni_txrate = rate; 213 /* 214 * Before associating a node has no rate set setup 215 * so we can't calculate any transmit codes to use. 216 * This is ok since we should never be sending anything 217 * but management frames and those always go at the 218 * lowest hardware rate. 219 */ 220 if (ni->ni_rates.rs_nrates > 0) { 221 amn->amn_tx_rix0 = sc->sc_rixmap[ 222 ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL]; 223 amn->amn_tx_rate0 = rt->info[amn->amn_tx_rix0].rateCode; 224 amn->amn_tx_rate0sp = amn->amn_tx_rate0 | 225 rt->info[amn->amn_tx_rix0].shortPreamble; 226 if (sc->sc_mrretry) { 227 amn->amn_tx_try0 = 1; 228 amn->amn_tx_try1 = 1; 229 amn->amn_tx_try2 = 1; 230 amn->amn_tx_try3 = 1; 231 if (--rate >= 0) { 232 rix = sc->sc_rixmap[ 233 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; 234 amn->amn_tx_rate1 = rt->info[rix].rateCode; 235 amn->amn_tx_rate1sp = amn->amn_tx_rate1 | 236 rt->info[rix].shortPreamble; 237 } else { 238 amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0; 239 } 240 if (--rate >= 0) { 241 rix = sc->sc_rixmap[ 242 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; 243 amn->amn_tx_rate2 = rt->info[rix].rateCode; 244 amn->amn_tx_rate2sp = amn->amn_tx_rate2 | 245 rt->info[rix].shortPreamble; 246 } else { 247 amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0; 248 } 249 if (rate > 0) { 250 /* NB: only do this if we didn't already do it above */ 251 amn->amn_tx_rate3 = rt->info[0].rateCode; 252 amn->amn_tx_rate3sp = 253 an->an_tx_rate3 | rt->info[0].shortPreamble; 254 } else { 255 amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0; 256 } 257 } else { 258 amn->amn_tx_try0 = ATH_TXMAXTRY; 259 /* theorically, these statements are useless because 260 * the code which uses them tests for an_tx_try0 == ATH_TXMAXTRY 261 */ 262 amn->amn_tx_try1 = 0; 263 amn->amn_tx_try2 = 0; 264 amn->amn_tx_try3 = 0; 265 amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0; 266 amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0; 267 amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0; 268 } 269 } 270 node_reset (amn); 271} 272 273/* 274 * Set the starting transmit rate for a node. 275 */ 276static void 277ath_rate_ctl_start(struct ath_softc *sc, struct ieee80211_node *ni) 278{ 279#define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL) 280 struct ieee80211com *ic = &sc->sc_ic; 281 int srate; 282 283 KASSERT(ni->ni_rates.rs_nrates > 0, ("no rates")); 284 if (ic->ic_fixed_rate == IEEE80211_FIXED_RATE_NONE) { 285 /* 286 * No fixed rate is requested. For 11b start with 287 * the highest negotiated rate; otherwise, for 11g 288 * and 11a, we start "in the middle" at 24Mb or 36Mb. 289 */ 290 srate = ni->ni_rates.rs_nrates - 1; 291 if (sc->sc_curmode != IEEE80211_MODE_11B) { 292 /* 293 * Scan the negotiated rate set to find the 294 * closest rate. 295 */ 296 /* NB: the rate set is assumed sorted */ 297 for (; srate >= 0 && RATE(srate) > 72; srate--) 298 ; 299 KASSERT(srate >= 0, ("bogus rate set")); 300 } 301 } else { 302 /* 303 * A fixed rate is to be used; ic_fixed_rate is an 304 * index into the supported rate set. 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 const struct ieee80211_rateset *rs = 310 &ic->ic_sup_rates[ic->ic_curmode]; 311 int r = rs->rs_rates[ic->ic_fixed_rate] & IEEE80211_RATE_VAL; 312 /* NB: the rate set is assumed sorted */ 313 srate = ni->ni_rates.rs_nrates - 1; 314 for (; srate >= 0 && RATE(srate) != r; srate--) 315 ; 316 KASSERT(srate >= 0, 317 ("fixed rate %d not in rate set", ic->ic_fixed_rate)); 318 } 319 ath_rate_update(sc, ni, srate); 320#undef RATE 321} 322 323static void 324ath_rate_cb(void *arg, struct ieee80211_node *ni) 325{ 326 struct ath_softc *sc = arg; 327 328 ath_rate_update(sc, ni, 0); 329} 330 331/* 332 * Reset the rate control state for each 802.11 state transition. 333 */ 334void 335ath_rate_newstate(struct ath_softc *sc, enum ieee80211_state state) 336{ 337 struct amrr_softc *asc = (struct amrr_softc *) sc->sc_rc; 338 struct ieee80211com *ic = &sc->sc_ic; 339 struct ieee80211_node *ni; 340 341 if (state == IEEE80211_S_INIT) { 342 callout_stop(&asc->timer); 343 return; 344 } 345 if (ic->ic_opmode == IEEE80211_M_STA) { 346 /* 347 * Reset local xmit state; this is really only 348 * meaningful when operating in station mode. 349 */ 350 ni = ic->ic_bss; 351 if (state == IEEE80211_S_RUN) { 352 ath_rate_ctl_start(sc, ni); 353 } else { 354 ath_rate_update(sc, ni, 0); 355 } 356 } else { 357 /* 358 * When operating as a station the node table holds 359 * the AP's that were discovered during scanning. 360 * For any other operating mode we want to reset the 361 * tx rate state of each node. 362 */ 363 ieee80211_iterate_nodes(&ic->ic_sta, ath_rate_cb, sc); 364 ath_rate_update(sc, ic->ic_bss, 0); 365 } 366 if (ic->ic_fixed_rate == IEEE80211_FIXED_RATE_NONE && 367 state == IEEE80211_S_RUN) { 368 int interval; 369 /* 370 * Start the background rate control thread if we 371 * are not configured to use a fixed xmit rate. 372 */ 373 interval = ath_rateinterval; 374 if (ic->ic_opmode == IEEE80211_M_STA) 375 interval /= 2; 376 callout_reset(&asc->timer, (interval * hz) / 1000, 377 ath_ratectl, &sc->sc_if); 378 } 379} 380 381/* 382 * Examine and potentially adjust the transmit rate. 383 */ 384static void 385ath_rate_ctl(void *arg, struct ieee80211_node *ni) 386{ 387 struct ath_softc *sc = arg; 388 struct amrr_node *amn = ATH_NODE_AMRR(ATH_NODE (ni)); 389 int old_rate; 390 391#define is_success(amn) \ 392(amn->amn_tx_try1_cnt < (amn->amn_tx_try0_cnt/10)) 393#define is_enough(amn) \ 394(amn->amn_tx_try0_cnt > 10) 395#define is_failure(amn) \ 396(amn->amn_tx_try1_cnt > (amn->amn_tx_try0_cnt/3)) 397#define is_max_rate(ni) \ 398((ni->ni_txrate + 1) >= ni->ni_rates.rs_nrates) 399#define is_min_rate(ni) \ 400(ni->ni_txrate == 0) 401 402 old_rate = ni->ni_txrate; 403 404 DPRINTF (sc, "cnt0: %d cnt1: %d cnt2: %d cnt3: %d -- threshold: %d\n", 405 amn->amn_tx_try0_cnt, 406 amn->amn_tx_try1_cnt, 407 amn->amn_tx_try2_cnt, 408 amn->amn_tx_try3_cnt, 409 amn->amn_success_threshold); 410 if (is_success (amn) && is_enough (amn)) { 411 amn->amn_success++; 412 if (amn->amn_success == amn->amn_success_threshold && 413 !is_max_rate (ni)) { 414 amn->amn_recovery = 1; 415 amn->amn_success = 0; 416 ni->ni_txrate++; 417 DPRINTF (sc, "increase rate to %d\n", ni->ni_txrate); 418 } else { 419 amn->amn_recovery = 0; 420 } 421 } else if (is_failure (amn)) { 422 amn->amn_success = 0; 423 if (!is_min_rate (ni)) { 424 if (amn->amn_recovery) { 425 /* recovery failure. */ 426 amn->amn_success_threshold *= 2; 427 amn->amn_success_threshold = min (amn->amn_success_threshold, 428 (u_int)ath_rate_max_success_threshold); 429 DPRINTF (sc, "decrease rate recovery thr: %d\n", amn->amn_success_threshold); 430 } else { 431 /* simple failure. */ 432 amn->amn_success_threshold = ath_rate_min_success_threshold; 433 DPRINTF (sc, "decrease rate normal thr: %d\n", amn->amn_success_threshold); 434 } 435 amn->amn_recovery = 0; 436 ni->ni_txrate--; 437 } else { 438 amn->amn_recovery = 0; 439 } 440 441 } 442 if (is_enough (amn) || old_rate != ni->ni_txrate) { 443 /* reset counters. */ 444 amn->amn_tx_try0_cnt = 0; 445 amn->amn_tx_try1_cnt = 0; 446 amn->amn_tx_try2_cnt = 0; 447 amn->amn_tx_try3_cnt = 0; 448 amn->amn_tx_failure_cnt = 0; 449 } 450 if (old_rate != ni->ni_txrate) { 451 ath_rate_update(sc, ni, ni->ni_txrate); 452 } 453} 454 455static void 456ath_ratectl(void *arg) 457{ 458 struct ifnet *ifp = arg; 459 struct ath_softc *sc = ifp->if_softc; 460 struct amrr_softc *asc = (struct amrr_softc *) sc->sc_rc; 461 struct ieee80211com *ic = &sc->sc_ic; 462 int interval; 463 464 if (ifp->if_drv_flags & IFF_DRV_RUNNING) { 465 sc->sc_stats.ast_rate_calls++; 466 467 if (ic->ic_opmode == IEEE80211_M_STA) 468 ath_rate_ctl(sc, ic->ic_bss); /* NB: no reference */ 469 else 470 ieee80211_iterate_nodes(&ic->ic_sta, ath_rate_ctl, sc); 471 } 472 interval = ath_rateinterval; 473 if (ic->ic_opmode == IEEE80211_M_STA) 474 interval /= 2; 475 callout_reset(&asc->timer, (interval * hz) / 1000, 476 ath_ratectl, &sc->sc_if); 477} 478 479static void 480ath_rate_sysctlattach(struct ath_softc *sc) 481{ 482 struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev); 483 struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev); 484 485 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 486 "rate_interval", CTLFLAG_RW, &ath_rateinterval, 0, 487 "rate control: operation interval (ms)"); 488 /* XXX bounds check values */ 489 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 490 "max_sucess_threshold", CTLFLAG_RW, 491 &ath_rate_max_success_threshold, 0, ""); 492 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 493 "min_sucess_threshold", CTLFLAG_RW, 494 &ath_rate_min_success_threshold, 0, ""); 495} 496 497struct ath_ratectrl * 498ath_rate_attach(struct ath_softc *sc) 499{ 500 struct amrr_softc *asc; 501 502 asc = malloc(sizeof(struct amrr_softc), M_DEVBUF, M_NOWAIT|M_ZERO); 503 if (asc == NULL) 504 return NULL; 505 asc->arc.arc_space = sizeof(struct amrr_node); 506 callout_init(&asc->timer, debug_mpsafenet ? CALLOUT_MPSAFE : 0); 507 ath_rate_sysctlattach(sc); 508 509 return &asc->arc; 510} 511 512void 513ath_rate_detach(struct ath_ratectrl *arc) 514{ 515 struct amrr_softc *asc = (struct amrr_softc *) arc; 516 517 callout_drain(&asc->timer); 518 free(asc, M_DEVBUF); 519} 520