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_inet.h" 49 #include "opt_wlan.h" 50 51 #include <sys/param.h> 52 #include <sys/systm.h> 53 #include <sys/sysctl.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 69 #include <net80211/ieee80211_var.h> 70 71 #include <net/bpf.h> 72 73 #ifdef INET 74 #include <netinet/in.h> 75 #include <netinet/if_ether.h> 76 #endif 77 78 #include <dev/ath/if_athvar.h> 79 #include <dev/ath/ath_rate/amrr/amrr.h> 80 #include <dev/ath/ath_hal/ah_desc.h> 81 82 static int ath_rateinterval = 1000; /* rate ctl interval (ms) */ 83 static int ath_rate_max_success_threshold = 10; 84 static int ath_rate_min_success_threshold = 1; 85 86 static void ath_rate_update(struct ath_softc *, struct ieee80211_node *, 87 int rate); 88 static void ath_rate_ctl_start(struct ath_softc *, struct ieee80211_node *); 89 static void ath_rate_ctl(void *, struct ieee80211_node *); 90 91 void 92 ath_rate_node_init(struct ath_softc *sc, struct ath_node *an) 93 { 94 /* NB: assumed to be zero'd by caller */ 95 } 96 97 void 98 ath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an) 99 { 100 } 101 102 void 103 ath_rate_findrate(struct ath_softc *sc, struct ath_node *an, 104 int shortPreamble, size_t frameLen, 105 u_int8_t *rix, int *try0, u_int8_t *txrate) 106 { 107 struct amrr_node *amn = ATH_NODE_AMRR(an); 108 109 *rix = amn->amn_tx_rix0; 110 *try0 = amn->amn_tx_try0; 111 if (shortPreamble) 112 *txrate = amn->amn_tx_rate0sp; 113 else 114 *txrate = amn->amn_tx_rate0; 115 } 116 117 void 118 ath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an, 119 struct ath_desc *ds, int shortPreamble, u_int8_t rix) 120 { 121 struct amrr_node *amn = ATH_NODE_AMRR(an); 122 123 ath_hal_setupxtxdesc(sc->sc_ah, ds 124 , amn->amn_tx_rate1sp, amn->amn_tx_try1 /* series 1 */ 125 , amn->amn_tx_rate2sp, amn->amn_tx_try2 /* series 2 */ 126 , amn->amn_tx_rate3sp, amn->amn_tx_try3 /* series 3 */ 127 ); 128 } 129 130 void 131 ath_rate_tx_complete(struct ath_softc *sc, struct ath_node *an, 132 const struct ath_buf *bf) 133 { 134 struct amrr_node *amn = ATH_NODE_AMRR(an); 135 const struct ath_tx_status *ts = &bf->bf_status.ds_txstat; 136 int sr = ts->ts_shortretry; 137 int lr = ts->ts_longretry; 138 int retry_count = sr + lr; 139 140 amn->amn_tx_try0_cnt++; 141 if (retry_count == 1) { 142 amn->amn_tx_try1_cnt++; 143 } else if (retry_count == 2) { 144 amn->amn_tx_try1_cnt++; 145 amn->amn_tx_try2_cnt++; 146 } else if (retry_count == 3) { 147 amn->amn_tx_try1_cnt++; 148 amn->amn_tx_try2_cnt++; 149 amn->amn_tx_try3_cnt++; 150 } else if (retry_count > 3) { 151 amn->amn_tx_try1_cnt++; 152 amn->amn_tx_try2_cnt++; 153 amn->amn_tx_try3_cnt++; 154 amn->amn_tx_failure_cnt++; 155 } 156 if (amn->amn_interval != 0 && 157 ticks - amn->amn_ticks > amn->amn_interval) { 158 ath_rate_ctl(sc, &an->an_node); 159 amn->amn_ticks = ticks; 160 } 161 } 162 163 void 164 ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew) 165 { 166 if (isnew) 167 ath_rate_ctl_start(sc, &an->an_node); 168 } 169 170 static void 171 node_reset(struct amrr_node *amn) 172 { 173 amn->amn_tx_try0_cnt = 0; 174 amn->amn_tx_try1_cnt = 0; 175 amn->amn_tx_try2_cnt = 0; 176 amn->amn_tx_try3_cnt = 0; 177 amn->amn_tx_failure_cnt = 0; 178 amn->amn_success = 0; 179 amn->amn_recovery = 0; 180 amn->amn_success_threshold = ath_rate_min_success_threshold; 181 } 182 183 184 /** 185 * The code below assumes that we are dealing with hardware multi rate retry 186 * I have no idea what will happen if you try to use this module with another 187 * type of hardware. Your machine might catch fire or it might work with 188 * horrible performance... 189 */ 190 static void 191 ath_rate_update(struct ath_softc *sc, struct ieee80211_node *ni, int rate) 192 { 193 struct ath_node *an = ATH_NODE(ni); 194 struct amrr_node *amn = ATH_NODE_AMRR(an); 195 struct ieee80211vap *vap = ni->ni_vap; 196 const HAL_RATE_TABLE *rt = sc->sc_currates; 197 u_int8_t rix; 198 199 KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode)); 200 201 IEEE80211_NOTE(vap, IEEE80211_MSG_RATECTL, ni, 202 "%s: set xmit rate to %dM", __func__, 203 ni->ni_rates.rs_nrates > 0 ? 204 (ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL) / 2 : 0); 205 206 amn->amn_rix = rate; 207 /* 208 * Before associating a node has no rate set setup 209 * so we can't calculate any transmit codes to use. 210 * This is ok since we should never be sending anything 211 * but management frames and those always go at the 212 * lowest hardware rate. 213 */ 214 if (ni->ni_rates.rs_nrates > 0) { 215 ni->ni_txrate = ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL; 216 amn->amn_tx_rix0 = sc->sc_rixmap[ni->ni_txrate]; 217 amn->amn_tx_rate0 = rt->info[amn->amn_tx_rix0].rateCode; 218 amn->amn_tx_rate0sp = amn->amn_tx_rate0 | 219 rt->info[amn->amn_tx_rix0].shortPreamble; 220 if (sc->sc_mrretry) { 221 amn->amn_tx_try0 = 1; 222 amn->amn_tx_try1 = 1; 223 amn->amn_tx_try2 = 1; 224 amn->amn_tx_try3 = 1; 225 if (--rate >= 0) { 226 rix = sc->sc_rixmap[ 227 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; 228 amn->amn_tx_rate1 = rt->info[rix].rateCode; 229 amn->amn_tx_rate1sp = amn->amn_tx_rate1 | 230 rt->info[rix].shortPreamble; 231 } else { 232 amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0; 233 } 234 if (--rate >= 0) { 235 rix = sc->sc_rixmap[ 236 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; 237 amn->amn_tx_rate2 = rt->info[rix].rateCode; 238 amn->amn_tx_rate2sp = amn->amn_tx_rate2 | 239 rt->info[rix].shortPreamble; 240 } else { 241 amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0; 242 } 243 if (rate > 0) { 244 /* NB: only do this if we didn't already do it above */ 245 amn->amn_tx_rate3 = rt->info[0].rateCode; 246 amn->amn_tx_rate3sp = 247 amn->amn_tx_rate3 | rt->info[0].shortPreamble; 248 } else { 249 amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0; 250 } 251 } else { 252 amn->amn_tx_try0 = ATH_TXMAXTRY; 253 /* theorically, these statements are useless because 254 * the code which uses them tests for an_tx_try0 == ATH_TXMAXTRY 255 */ 256 amn->amn_tx_try1 = 0; 257 amn->amn_tx_try2 = 0; 258 amn->amn_tx_try3 = 0; 259 amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0; 260 amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0; 261 amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0; 262 } 263 } 264 node_reset(amn); 265 266 amn->amn_interval = ath_rateinterval; 267 if (vap->iv_opmode == IEEE80211_M_STA) 268 amn->amn_interval /= 2; 269 amn->amn_interval = (amn->amn_interval * hz) / 1000; 270 } 271 272 /* 273 * Set the starting transmit rate for a node. 274 */ 275 static void 276 ath_rate_ctl_start(struct ath_softc *sc, struct ieee80211_node *ni) 277 { 278 #define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL) 279 const struct ieee80211_txparam *tp = ni->ni_txparms; 280 int srate; 281 282 KASSERT(ni->ni_rates.rs_nrates > 0, ("no rates")); 283 if (tp == NULL || tp->ucastrate == IEEE80211_FIXED_RATE_NONE) { 284 /* 285 * No fixed rate is requested. For 11b start with 286 * the highest negotiated rate; otherwise, for 11g 287 * and 11a, we start "in the middle" at 24Mb or 36Mb. 288 */ 289 srate = ni->ni_rates.rs_nrates - 1; 290 if (sc->sc_curmode != IEEE80211_MODE_11B) { 291 /* 292 * Scan the negotiated rate set to find the 293 * closest rate. 294 */ 295 /* NB: the rate set is assumed sorted */ 296 for (; srate >= 0 && RATE(srate) > 72; srate--) 297 ; 298 } 299 } else { 300 /* 301 * A fixed rate is to be used; ic_fixed_rate is the 302 * IEEE code for this rate (sans basic bit). Convert this 303 * to the index into the negotiated rate set for 304 * the node. We know the rate is there because the 305 * rate set is checked when the station associates. 306 */ 307 /* NB: the rate set is assumed sorted */ 308 srate = ni->ni_rates.rs_nrates - 1; 309 for (; srate >= 0 && RATE(srate) != tp->ucastrate; srate--) 310 ; 311 } 312 /* 313 * The selected rate may not be available due to races 314 * and mode settings. Also orphaned nodes created in 315 * adhoc mode may not have any rate set so this lookup 316 * can fail. This is not fatal. 317 */ 318 ath_rate_update(sc, ni, srate < 0 ? 0 : srate); 319 #undef RATE 320 } 321 322 /* 323 * Examine and potentially adjust the transmit rate. 324 */ 325 static void 326 ath_rate_ctl(void *arg, struct ieee80211_node *ni) 327 { 328 struct ath_softc *sc = arg; 329 struct amrr_node *amn = ATH_NODE_AMRR(ATH_NODE (ni)); 330 int rix; 331 332 #define is_success(amn) \ 333 (amn->amn_tx_try1_cnt < (amn->amn_tx_try0_cnt/10)) 334 #define is_enough(amn) \ 335 (amn->amn_tx_try0_cnt > 10) 336 #define is_failure(amn) \ 337 (amn->amn_tx_try1_cnt > (amn->amn_tx_try0_cnt/3)) 338 339 rix = amn->amn_rix; 340 341 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, 342 "cnt0: %d cnt1: %d cnt2: %d cnt3: %d -- threshold: %d", 343 amn->amn_tx_try0_cnt, amn->amn_tx_try1_cnt, amn->amn_tx_try2_cnt, 344 amn->amn_tx_try3_cnt, amn->amn_success_threshold); 345 if (is_success (amn) && is_enough (amn)) { 346 amn->amn_success++; 347 if (amn->amn_success == amn->amn_success_threshold && 348 rix + 1 < ni->ni_rates.rs_nrates) { 349 amn->amn_recovery = 1; 350 amn->amn_success = 0; 351 rix++; 352 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, 353 "increase rate to %d", rix); 354 } else { 355 amn->amn_recovery = 0; 356 } 357 } else if (is_failure (amn)) { 358 amn->amn_success = 0; 359 if (rix > 0) { 360 if (amn->amn_recovery) { 361 /* recovery failure. */ 362 amn->amn_success_threshold *= 2; 363 amn->amn_success_threshold = min (amn->amn_success_threshold, 364 (u_int)ath_rate_max_success_threshold); 365 IEEE80211_NOTE(ni->ni_vap, 366 IEEE80211_MSG_RATECTL, ni, 367 "decrease rate recovery thr: %d", 368 amn->amn_success_threshold); 369 } else { 370 /* simple failure. */ 371 amn->amn_success_threshold = ath_rate_min_success_threshold; 372 IEEE80211_NOTE(ni->ni_vap, 373 IEEE80211_MSG_RATECTL, ni, 374 "decrease rate normal thr: %d", 375 amn->amn_success_threshold); 376 } 377 amn->amn_recovery = 0; 378 rix--; 379 } else { 380 amn->amn_recovery = 0; 381 } 382 383 } 384 if (is_enough (amn) || rix != amn->amn_rix) { 385 /* reset counters. */ 386 amn->amn_tx_try0_cnt = 0; 387 amn->amn_tx_try1_cnt = 0; 388 amn->amn_tx_try2_cnt = 0; 389 amn->amn_tx_try3_cnt = 0; 390 amn->amn_tx_failure_cnt = 0; 391 } 392 if (rix != amn->amn_rix) { 393 ath_rate_update(sc, ni, rix); 394 } 395 } 396 397 static void 398 ath_rate_sysctlattach(struct ath_softc *sc) 399 { 400 struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev); 401 struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev); 402 403 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 404 "rate_interval", CTLFLAG_RW, &ath_rateinterval, 0, 405 "rate control: operation interval (ms)"); 406 /* XXX bounds check values */ 407 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 408 "max_sucess_threshold", CTLFLAG_RW, 409 &ath_rate_max_success_threshold, 0, ""); 410 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 411 "min_sucess_threshold", CTLFLAG_RW, 412 &ath_rate_min_success_threshold, 0, ""); 413 } 414 415 struct ath_ratectrl * 416 ath_rate_attach(struct ath_softc *sc) 417 { 418 struct amrr_softc *asc; 419 420 asc = malloc(sizeof(struct amrr_softc), M_DEVBUF, M_NOWAIT|M_ZERO); 421 if (asc == NULL) 422 return NULL; 423 asc->arc.arc_space = sizeof(struct amrr_node); 424 ath_rate_sysctlattach(sc); 425 426 return &asc->arc; 427 } 428 429 void 430 ath_rate_detach(struct ath_ratectrl *arc) 431 { 432 struct amrr_softc *asc = (struct amrr_softc *) arc; 433 434 free(asc, M_DEVBUF); 435 } 436