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("$FreeBSD$"); 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_ath.h" 49 #include "opt_inet.h" 50 #include "opt_wlan.h" 51 52 #include <sys/param.h> 53 #include <sys/systm.h> 54 #include <sys/sysctl.h> 55 #include <sys/kernel.h> 56 #include <sys/lock.h> 57 #include <sys/mutex.h> 58 #include <sys/errno.h> 59 60 #include <sys/bus.h> 61 62 #include <sys/socket.h> 63 64 #include <net/if.h> 65 #include <net/if_media.h> 66 #include <net/if_arp.h> 67 68 #include <netproto/802_11/ieee80211_var.h> 69 70 #include <net/bpf.h> 71 72 #ifdef INET 73 #include <netinet/in.h> 74 #include <netinet/if_ether.h> 75 #endif 76 77 #include <dev/netif/ath/ath/if_athvar.h> 78 #include <dev/netif/ath/ath_rate/amrr/amrr.h> 79 #include <dev/netif/ath/ath_hal/ah_desc.h> 80 81 static int ath_rateinterval = 1000; /* rate ctl interval (ms) */ 82 static int ath_rate_max_success_threshold = 10; 83 static int ath_rate_min_success_threshold = 1; 84 85 static void ath_rate_update(struct ath_softc *, struct ieee80211_node *, 86 int rate); 87 static void ath_rate_ctl_start(struct ath_softc *, struct ieee80211_node *); 88 static void ath_rate_ctl(void *, struct ieee80211_node *); 89 90 void 91 ath_rate_node_init(struct ath_softc *sc, struct ath_node *an) 92 { 93 /* NB: assumed to be zero'd by caller */ 94 } 95 96 void 97 ath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an) 98 { 99 } 100 101 void 102 ath_rate_findrate(struct ath_softc *sc, struct ath_node *an, 103 int shortPreamble, size_t frameLen, 104 u_int8_t *rix, int *try0, u_int8_t *txrate) 105 { 106 struct amrr_node *amn = ATH_NODE_AMRR(an); 107 108 *rix = amn->amn_tx_rix0; 109 *try0 = amn->amn_tx_try0; 110 if (shortPreamble) 111 *txrate = amn->amn_tx_rate0sp; 112 else 113 *txrate = amn->amn_tx_rate0; 114 } 115 116 /* 117 * Get the TX rates. 118 * 119 * The short preamble bits aren't set here; the caller should augment 120 * the returned rate with the relevant preamble rate flag. 121 */ 122 void 123 ath_rate_getxtxrates(struct ath_softc *sc, struct ath_node *an, 124 uint8_t rix0, struct ath_rc_series *rc) 125 { 126 struct amrr_node *amn = ATH_NODE_AMRR(an); 127 128 rc[0].flags = rc[1].flags = rc[2].flags = rc[3].flags = 0; 129 130 rc[0].rix = amn->amn_tx_rate0; 131 rc[1].rix = amn->amn_tx_rate1; 132 rc[2].rix = amn->amn_tx_rate2; 133 rc[3].rix = amn->amn_tx_rate3; 134 135 rc[0].tries = amn->amn_tx_try0; 136 rc[1].tries = amn->amn_tx_try1; 137 rc[2].tries = amn->amn_tx_try2; 138 rc[3].tries = amn->amn_tx_try3; 139 } 140 141 142 void 143 ath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an, 144 struct ath_desc *ds, int shortPreamble, u_int8_t rix) 145 { 146 struct amrr_node *amn = ATH_NODE_AMRR(an); 147 148 ath_hal_setupxtxdesc(sc->sc_ah, ds 149 , amn->amn_tx_rate1sp, amn->amn_tx_try1 /* series 1 */ 150 , amn->amn_tx_rate2sp, amn->amn_tx_try2 /* series 2 */ 151 , amn->amn_tx_rate3sp, amn->amn_tx_try3 /* series 3 */ 152 ); 153 } 154 155 void 156 ath_rate_tx_complete(struct ath_softc *sc, struct ath_node *an, 157 const struct ath_rc_series *rc, const struct ath_tx_status *ts, 158 int frame_size, int nframes, int nbad) 159 { 160 struct amrr_node *amn = ATH_NODE_AMRR(an); 161 int sr = ts->ts_shortretry; 162 int lr = ts->ts_longretry; 163 int retry_count = sr + lr; 164 165 amn->amn_tx_try0_cnt++; 166 if (retry_count == 1) { 167 amn->amn_tx_try1_cnt++; 168 } else if (retry_count == 2) { 169 amn->amn_tx_try1_cnt++; 170 amn->amn_tx_try2_cnt++; 171 } else if (retry_count == 3) { 172 amn->amn_tx_try1_cnt++; 173 amn->amn_tx_try2_cnt++; 174 amn->amn_tx_try3_cnt++; 175 } else if (retry_count > 3) { 176 amn->amn_tx_try1_cnt++; 177 amn->amn_tx_try2_cnt++; 178 amn->amn_tx_try3_cnt++; 179 amn->amn_tx_failure_cnt++; 180 } 181 if (amn->amn_interval != 0 && 182 ticks - amn->amn_ticks > amn->amn_interval) { 183 ath_rate_ctl(sc, &an->an_node); 184 amn->amn_ticks = ticks; 185 } 186 } 187 188 void 189 ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew) 190 { 191 if (isnew) 192 ath_rate_ctl_start(sc, &an->an_node); 193 } 194 195 static void 196 node_reset(struct amrr_node *amn) 197 { 198 amn->amn_tx_try0_cnt = 0; 199 amn->amn_tx_try1_cnt = 0; 200 amn->amn_tx_try2_cnt = 0; 201 amn->amn_tx_try3_cnt = 0; 202 amn->amn_tx_failure_cnt = 0; 203 amn->amn_success = 0; 204 amn->amn_recovery = 0; 205 amn->amn_success_threshold = ath_rate_min_success_threshold; 206 } 207 208 209 /** 210 * The code below assumes that we are dealing with hardware multi rate retry 211 * I have no idea what will happen if you try to use this module with another 212 * type of hardware. Your machine might catch fire or it might work with 213 * horrible performance... 214 */ 215 static void 216 ath_rate_update(struct ath_softc *sc, struct ieee80211_node *ni, int rate) 217 { 218 struct ath_node *an = ATH_NODE(ni); 219 struct amrr_node *amn = ATH_NODE_AMRR(an); 220 struct ieee80211vap *vap = ni->ni_vap; 221 const HAL_RATE_TABLE *rt = sc->sc_currates; 222 u_int8_t rix; 223 224 KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode)); 225 226 IEEE80211_NOTE(vap, IEEE80211_MSG_RATECTL, ni, 227 "%s: set xmit rate to %dM", __func__, 228 ni->ni_rates.rs_nrates > 0 ? 229 (ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL) / 2 : 0); 230 231 amn->amn_rix = rate; 232 /* 233 * Before associating a node has no rate set setup 234 * so we can't calculate any transmit codes to use. 235 * This is ok since we should never be sending anything 236 * but management frames and those always go at the 237 * lowest hardware rate. 238 */ 239 if (ni->ni_rates.rs_nrates > 0) { 240 ni->ni_txrate = ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL; 241 amn->amn_tx_rix0 = sc->sc_rixmap[ni->ni_txrate]; 242 amn->amn_tx_rate0 = rt->info[amn->amn_tx_rix0].rateCode; 243 amn->amn_tx_rate0sp = amn->amn_tx_rate0 | 244 rt->info[amn->amn_tx_rix0].shortPreamble; 245 if (sc->sc_mrretry) { 246 amn->amn_tx_try0 = 1; 247 amn->amn_tx_try1 = 1; 248 amn->amn_tx_try2 = 1; 249 amn->amn_tx_try3 = 1; 250 if (--rate >= 0) { 251 rix = sc->sc_rixmap[ 252 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; 253 amn->amn_tx_rate1 = rt->info[rix].rateCode; 254 amn->amn_tx_rate1sp = amn->amn_tx_rate1 | 255 rt->info[rix].shortPreamble; 256 } else { 257 amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0; 258 } 259 if (--rate >= 0) { 260 rix = sc->sc_rixmap[ 261 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; 262 amn->amn_tx_rate2 = rt->info[rix].rateCode; 263 amn->amn_tx_rate2sp = amn->amn_tx_rate2 | 264 rt->info[rix].shortPreamble; 265 } else { 266 amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0; 267 } 268 if (rate > 0) { 269 /* NB: only do this if we didn't already do it above */ 270 amn->amn_tx_rate3 = rt->info[0].rateCode; 271 amn->amn_tx_rate3sp = 272 amn->amn_tx_rate3 | rt->info[0].shortPreamble; 273 } else { 274 amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0; 275 } 276 } else { 277 amn->amn_tx_try0 = ATH_TXMAXTRY; 278 /* theorically, these statements are useless because 279 * the code which uses them tests for an_tx_try0 == ATH_TXMAXTRY 280 */ 281 amn->amn_tx_try1 = 0; 282 amn->amn_tx_try2 = 0; 283 amn->amn_tx_try3 = 0; 284 amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0; 285 amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0; 286 amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0; 287 } 288 } 289 node_reset(amn); 290 291 amn->amn_interval = ath_rateinterval; 292 if (vap->iv_opmode == IEEE80211_M_STA) 293 amn->amn_interval /= 2; 294 amn->amn_interval = (amn->amn_interval * hz) / 1000; 295 } 296 297 /* 298 * Set the starting transmit rate for a node. 299 */ 300 static void 301 ath_rate_ctl_start(struct ath_softc *sc, struct ieee80211_node *ni) 302 { 303 #define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL) 304 const struct ieee80211_txparam *tp = ni->ni_txparms; 305 int srate; 306 307 KASSERT(ni->ni_rates.rs_nrates > 0, ("no rates")); 308 if (tp == NULL || tp->ucastrate == IEEE80211_FIXED_RATE_NONE) { 309 /* 310 * No fixed rate is requested. For 11b start with 311 * the highest negotiated rate; otherwise, for 11g 312 * and 11a, we start "in the middle" at 24Mb or 36Mb. 313 */ 314 srate = ni->ni_rates.rs_nrates - 1; 315 if (sc->sc_curmode != IEEE80211_MODE_11B) { 316 /* 317 * Scan the negotiated rate set to find the 318 * closest rate. 319 */ 320 /* NB: the rate set is assumed sorted */ 321 for (; srate >= 0 && RATE(srate) > 72; srate--) 322 ; 323 } 324 } else { 325 /* 326 * A fixed rate is to be used; ic_fixed_rate is the 327 * IEEE code for this rate (sans basic bit). Convert this 328 * to the index into the negotiated rate set for 329 * the node. We know the rate is there because the 330 * rate set is checked when the station associates. 331 */ 332 /* NB: the rate set is assumed sorted */ 333 srate = ni->ni_rates.rs_nrates - 1; 334 for (; srate >= 0 && RATE(srate) != tp->ucastrate; srate--) 335 ; 336 } 337 /* 338 * The selected rate may not be available due to races 339 * and mode settings. Also orphaned nodes created in 340 * adhoc mode may not have any rate set so this lookup 341 * can fail. This is not fatal. 342 */ 343 ath_rate_update(sc, ni, srate < 0 ? 0 : srate); 344 #undef RATE 345 } 346 347 /* 348 * Examine and potentially adjust the transmit rate. 349 */ 350 static void 351 ath_rate_ctl(void *arg, struct ieee80211_node *ni) 352 { 353 struct ath_softc *sc = arg; 354 struct amrr_node *amn = ATH_NODE_AMRR(ATH_NODE (ni)); 355 int rix; 356 357 #define is_success(amn) \ 358 (amn->amn_tx_try1_cnt < (amn->amn_tx_try0_cnt/10)) 359 #define is_enough(amn) \ 360 (amn->amn_tx_try0_cnt > 10) 361 #define is_failure(amn) \ 362 (amn->amn_tx_try1_cnt > (amn->amn_tx_try0_cnt/3)) 363 364 rix = amn->amn_rix; 365 366 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, 367 "cnt0: %d cnt1: %d cnt2: %d cnt3: %d -- threshold: %d", 368 amn->amn_tx_try0_cnt, amn->amn_tx_try1_cnt, amn->amn_tx_try2_cnt, 369 amn->amn_tx_try3_cnt, amn->amn_success_threshold); 370 if (is_success (amn) && is_enough (amn)) { 371 amn->amn_success++; 372 if (amn->amn_success == amn->amn_success_threshold && 373 rix + 1 < ni->ni_rates.rs_nrates) { 374 amn->amn_recovery = 1; 375 amn->amn_success = 0; 376 rix++; 377 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, 378 "increase rate to %d", rix); 379 } else { 380 amn->amn_recovery = 0; 381 } 382 } else if (is_failure (amn)) { 383 amn->amn_success = 0; 384 if (rix > 0) { 385 if (amn->amn_recovery) { 386 /* recovery failure. */ 387 amn->amn_success_threshold *= 2; 388 amn->amn_success_threshold = min (amn->amn_success_threshold, 389 (u_int)ath_rate_max_success_threshold); 390 IEEE80211_NOTE(ni->ni_vap, 391 IEEE80211_MSG_RATECTL, ni, 392 "decrease rate recovery thr: %d", 393 amn->amn_success_threshold); 394 } else { 395 /* simple failure. */ 396 amn->amn_success_threshold = ath_rate_min_success_threshold; 397 IEEE80211_NOTE(ni->ni_vap, 398 IEEE80211_MSG_RATECTL, ni, 399 "decrease rate normal thr: %d", 400 amn->amn_success_threshold); 401 } 402 amn->amn_recovery = 0; 403 rix--; 404 } else { 405 amn->amn_recovery = 0; 406 } 407 408 } 409 if (is_enough (amn) || rix != amn->amn_rix) { 410 /* reset counters. */ 411 amn->amn_tx_try0_cnt = 0; 412 amn->amn_tx_try1_cnt = 0; 413 amn->amn_tx_try2_cnt = 0; 414 amn->amn_tx_try3_cnt = 0; 415 amn->amn_tx_failure_cnt = 0; 416 } 417 if (rix != amn->amn_rix) { 418 ath_rate_update(sc, ni, rix); 419 } 420 } 421 422 static int 423 ath_rate_fetch_node_stats(struct ath_softc *sc, struct ath_node *an, 424 struct ath_rateioctl *re) 425 { 426 427 return (EINVAL); 428 } 429 430 static void 431 ath_rate_sysctlattach(struct ath_softc *sc) 432 { 433 struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev); 434 struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev); 435 436 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 437 "rate_interval", CTLFLAG_RW, &ath_rateinterval, 0, 438 "rate control: operation interval (ms)"); 439 /* XXX bounds check values */ 440 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 441 "max_sucess_threshold", CTLFLAG_RW, 442 &ath_rate_max_success_threshold, 0, ""); 443 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 444 "min_sucess_threshold", CTLFLAG_RW, 445 &ath_rate_min_success_threshold, 0, ""); 446 } 447 448 struct ath_ratectrl * 449 ath_rate_attach(struct ath_softc *sc) 450 { 451 struct amrr_softc *asc; 452 453 asc = kmalloc(sizeof(struct amrr_softc), M_DEVBUF, M_INTWAIT|M_ZERO); 454 if (asc == NULL) 455 return NULL; 456 asc->arc.arc_space = sizeof(struct amrr_node); 457 ath_rate_sysctlattach(sc); 458 459 return &asc->arc; 460 } 461 462 void 463 ath_rate_detach(struct ath_ratectrl *arc) 464 { 465 struct amrr_softc *asc = (struct amrr_softc *) arc; 466 467 kfree(asc, M_DEVBUF); 468 } 469 470 /* 471 * Module glue. 472 */ 473 static int 474 amrr_modevent(module_t mod, int type, void *unused) 475 { 476 int error; 477 478 wlan_serialize_enter(); 479 480 switch (type) { 481 case MOD_LOAD: 482 if (bootverbose) { 483 kprintf("ath_rate: <AMRR rate control " 484 "algorithm> version 0.1\n"); 485 } 486 error = 0; 487 break; 488 case MOD_UNLOAD: 489 error = 0; 490 break; 491 default: 492 error = EINVAL; 493 break; 494 } 495 wlan_serialize_exit(); 496 497 return error; 498 } 499 500 static moduledata_t amrr_mod = { 501 "ath_rate", 502 amrr_modevent, 503 0 504 }; 505 506 DECLARE_MODULE(ath_rate, amrr_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST); 507 MODULE_VERSION(ath_rate, 1); 508 MODULE_DEPEND(ath_rate, ath_hal, 1, 1, 1); 509 MODULE_DEPEND(ath_rate, wlan, 1, 1, 1); 510