1138569Ssam/*- 2170375Ssam * Copyright (c) 2002-2007 Sam Leffler, Errno Consulting 3138569Ssam * All rights reserved. 4138569Ssam * 5138569Ssam * Redistribution and use in source and binary forms, with or without 6138569Ssam * modification, are permitted provided that the following conditions 7138569Ssam * are met: 8138569Ssam * 1. Redistributions of source code must retain the above copyright 9138569Ssam * notice, this list of conditions and the following disclaimer, 10138569Ssam * without modification. 11138569Ssam * 2. Redistributions in binary form must reproduce at minimum a disclaimer 12138569Ssam * similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any 13138569Ssam * redistribution must be conditioned upon including a substantially 14138569Ssam * similar Disclaimer requirement for further binary redistribution. 15138569Ssam * 16138569Ssam * NO WARRANTY 17138569Ssam * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 18138569Ssam * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 19138569Ssam * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY 20138569Ssam * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 21138569Ssam * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, 22138569Ssam * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 23138569Ssam * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 24138569Ssam * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER 25138569Ssam * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 26138569Ssam * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 27138569Ssam * THE POSSIBILITY OF SUCH DAMAGES. 28138569Ssam */ 29138569Ssam 30138569Ssam#include <sys/cdefs.h> 31138569Ssam__FBSDID("$FreeBSD$"); 32138569Ssam 33138569Ssam/* 34138569Ssam * Atsushi Onoe's rate control algorithm. 35138569Ssam */ 36237529Sadrian#include "opt_ath.h" 37138569Ssam#include "opt_inet.h" 38178354Ssam#include "opt_wlan.h" 39138569Ssam 40138569Ssam#include <sys/param.h> 41138569Ssam#include <sys/systm.h> 42138569Ssam#include <sys/sysctl.h> 43138569Ssam#include <sys/kernel.h> 44138569Ssam#include <sys/lock.h> 45138569Ssam#include <sys/mutex.h> 46138569Ssam#include <sys/errno.h> 47138569Ssam 48138569Ssam#include <machine/bus.h> 49138569Ssam#include <machine/resource.h> 50138569Ssam#include <sys/bus.h> 51138569Ssam 52138569Ssam#include <sys/socket.h> 53138569Ssam 54138569Ssam#include <net/if.h> 55138569Ssam#include <net/if_media.h> 56138569Ssam#include <net/if_arp.h> 57138569Ssam#include <net/ethernet.h> /* XXX for ether_sprintf */ 58138569Ssam 59138569Ssam#include <net80211/ieee80211_var.h> 60138569Ssam 61138569Ssam#include <net/bpf.h> 62138569Ssam 63138569Ssam#ifdef INET 64138569Ssam#include <netinet/in.h> 65138569Ssam#include <netinet/if_ether.h> 66138569Ssam#endif 67138569Ssam 68138569Ssam#include <dev/ath/if_athvar.h> 69138569Ssam#include <dev/ath/ath_rate/onoe/onoe.h> 70185522Ssam#include <dev/ath/ath_hal/ah_desc.h> 71138569Ssam 72138569Ssam/* 73138569Ssam * Default parameters for the rate control algorithm. These are 74138569Ssam * all tunable with sysctls. The rate controller runs periodically 75138569Ssam * (each ath_rateinterval ms) analyzing transmit statistics for each 76138569Ssam * neighbor/station (when operating in station mode this is only the AP). 77138569Ssam * If transmits look to be working well over a sampling period then 78138569Ssam * it gives a "raise rate credit". If transmits look to not be working 79138569Ssam * well than it deducts a credit. If the credits cross a threshold then 80138569Ssam * the transmit rate is raised. Various error conditions force the 81138569Ssam * the transmit rate to be dropped. 82138569Ssam * 83138569Ssam * The decision to issue/deduct a credit is based on the errors and 84138569Ssam * retries accumulated over the sampling period. ath_rate_raise defines 85138569Ssam * the percent of retransmits for which a credit is issued/deducted. 86138569Ssam * ath_rate_raise_threshold defines the threshold on credits at which 87138569Ssam * the transmit rate is increased. 88138569Ssam * 89138569Ssam * XXX this algorithm is flawed. 90138569Ssam */ 91138569Ssamstatic int ath_rateinterval = 1000; /* rate ctl interval (ms) */ 92138569Ssamstatic int ath_rate_raise = 10; /* add credit threshold */ 93138569Ssamstatic int ath_rate_raise_threshold = 10; /* rate ctl raise threshold */ 94138569Ssam 95138569Ssamstatic void ath_rate_update(struct ath_softc *, struct ieee80211_node *, 96138569Ssam int rate); 97138569Ssamstatic void ath_rate_ctl_start(struct ath_softc *, struct ieee80211_node *); 98138569Ssamstatic void ath_rate_ctl(void *, struct ieee80211_node *); 99138569Ssam 100138569Ssamvoid 101138569Ssamath_rate_node_init(struct ath_softc *sc, struct ath_node *an) 102138569Ssam{ 103138569Ssam /* NB: assumed to be zero'd by caller */ 104138569Ssam} 105138569Ssam 106138569Ssamvoid 107138569Ssamath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an) 108138569Ssam{ 109138569Ssam} 110138569Ssam 111138569Ssamvoid 112138569Ssamath_rate_findrate(struct ath_softc *sc, struct ath_node *an, 113144546Ssam int shortPreamble, size_t frameLen, 114138569Ssam u_int8_t *rix, int *try0, u_int8_t *txrate) 115138569Ssam{ 116138569Ssam struct onoe_node *on = ATH_NODE_ONOE(an); 117138569Ssam 118138569Ssam *rix = on->on_tx_rix0; 119138569Ssam *try0 = on->on_tx_try0; 120138569Ssam if (shortPreamble) 121138569Ssam *txrate = on->on_tx_rate0sp; 122138569Ssam else 123138569Ssam *txrate = on->on_tx_rate0; 124138569Ssam} 125138569Ssam 126218160Sadrian/* 127218160Sadrian * Get the TX rates. 128218160Sadrian * 129218160Sadrian * The short preamble bits aren't set here; the caller should augment 130218160Sadrian * the returned rate with the relevant preamble rate flag. 131218160Sadrian */ 132138569Ssamvoid 133218160Sadrianath_rate_getxtxrates(struct ath_softc *sc, struct ath_node *an, 134227364Sadrian uint8_t rix0, struct ath_rc_series *rc) 135218160Sadrian{ 136218160Sadrian struct onoe_node *on = ATH_NODE_ONOE(an); 137218160Sadrian 138227364Sadrian rc[0].flags = rc[1].flags = rc[2].flags = rc[3].flags = 0; 139218160Sadrian 140227364Sadrian rc[0].rix = on->on_tx_rate0; 141227364Sadrian rc[1].rix = on->on_tx_rate1; 142227364Sadrian rc[2].rix = on->on_tx_rate2; 143227364Sadrian rc[3].rix = on->on_tx_rate3; 144227364Sadrian 145227364Sadrian rc[0].tries = on->on_tx_try0; 146227364Sadrian rc[1].tries = 2; 147227364Sadrian rc[2].tries = 2; 148227364Sadrian rc[3].tries = 2; 149218160Sadrian} 150218160Sadrian 151218160Sadrianvoid 152138569Ssamath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an, 153144546Ssam struct ath_desc *ds, int shortPreamble, u_int8_t rix) 154138569Ssam{ 155138569Ssam struct onoe_node *on = ATH_NODE_ONOE(an); 156138569Ssam 157138569Ssam ath_hal_setupxtxdesc(sc->sc_ah, ds 158138569Ssam , on->on_tx_rate1sp, 2 /* series 1 */ 159138569Ssam , on->on_tx_rate2sp, 2 /* series 2 */ 160138569Ssam , on->on_tx_rate3sp, 2 /* series 3 */ 161138569Ssam ); 162138569Ssam} 163138569Ssam 164138569Ssamvoid 165144347Ssamath_rate_tx_complete(struct ath_softc *sc, struct ath_node *an, 166227364Sadrian const struct ath_rc_series *rc, const struct ath_tx_status *ts, 167227364Sadrian int frame_size, int nframes, int nbad) 168138569Ssam{ 169138569Ssam struct onoe_node *on = ATH_NODE_ONOE(an); 170138569Ssam 171165185Ssam if (ts->ts_status == 0) 172138569Ssam on->on_tx_ok++; 173138569Ssam else 174138569Ssam on->on_tx_err++; 175165185Ssam on->on_tx_retr += ts->ts_shortretry 176165185Ssam + ts->ts_longretry; 177178354Ssam if (on->on_interval != 0 && ticks - on->on_ticks > on->on_interval) { 178178354Ssam ath_rate_ctl(sc, &an->an_node); 179178354Ssam on->on_ticks = ticks; 180178354Ssam } 181138569Ssam} 182138569Ssam 183138569Ssamvoid 184138569Ssamath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew) 185138569Ssam{ 186138569Ssam if (isnew) 187138569Ssam ath_rate_ctl_start(sc, &an->an_node); 188138569Ssam} 189138569Ssam 190138569Ssamstatic void 191138569Ssamath_rate_update(struct ath_softc *sc, struct ieee80211_node *ni, int rate) 192138569Ssam{ 193138569Ssam struct ath_node *an = ATH_NODE(ni); 194138569Ssam struct onoe_node *on = ATH_NODE_ONOE(an); 195178354Ssam struct ieee80211vap *vap = ni->ni_vap; 196138569Ssam const HAL_RATE_TABLE *rt = sc->sc_currates; 197138569Ssam u_int8_t rix; 198138569Ssam 199138569Ssam KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode)); 200138569Ssam 201178354Ssam IEEE80211_NOTE(vap, IEEE80211_MSG_RATECTL, ni, 202178354Ssam "%s: set xmit rate to %dM", __func__, 203178354Ssam ni->ni_rates.rs_nrates > 0 ? 204138569Ssam (ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL) / 2 : 0); 205138569Ssam 206138569Ssam /* 207138569Ssam * Before associating a node has no rate set setup 208138569Ssam * so we can't calculate any transmit codes to use. 209138569Ssam * This is ok since we should never be sending anything 210138569Ssam * but management frames and those always go at the 211138569Ssam * lowest hardware rate. 212138569Ssam */ 213138569Ssam if (ni->ni_rates.rs_nrates == 0) 214138569Ssam goto done; 215178354Ssam on->on_rix = rate; 216178354Ssam ni->ni_txrate = ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL; 217178354Ssam on->on_tx_rix0 = sc->sc_rixmap[ni->ni_txrate]; 218138569Ssam on->on_tx_rate0 = rt->info[on->on_tx_rix0].rateCode; 219138569Ssam 220138569Ssam on->on_tx_rate0sp = on->on_tx_rate0 | 221138569Ssam rt->info[on->on_tx_rix0].shortPreamble; 222138569Ssam if (sc->sc_mrretry) { 223138569Ssam /* 224138569Ssam * Hardware supports multi-rate retry; setup two 225138569Ssam * step-down retry rates and make the lowest rate 226138569Ssam * be the ``last chance''. We use 4, 2, 2, 2 tries 227138569Ssam * respectively (4 is set here, the rest are fixed 228138569Ssam * in the xmit routine). 229138569Ssam */ 230138569Ssam on->on_tx_try0 = 1 + 3; /* 4 tries at rate 0 */ 231138569Ssam if (--rate >= 0) { 232138569Ssam rix = sc->sc_rixmap[ 233138569Ssam ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; 234138569Ssam on->on_tx_rate1 = rt->info[rix].rateCode; 235138569Ssam on->on_tx_rate1sp = on->on_tx_rate1 | 236138569Ssam rt->info[rix].shortPreamble; 237138569Ssam } else { 238138569Ssam on->on_tx_rate1 = on->on_tx_rate1sp = 0; 239138569Ssam } 240138569Ssam if (--rate >= 0) { 241138569Ssam rix = sc->sc_rixmap[ 242138569Ssam ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; 243138569Ssam on->on_tx_rate2 = rt->info[rix].rateCode; 244138569Ssam on->on_tx_rate2sp = on->on_tx_rate2 | 245138569Ssam rt->info[rix].shortPreamble; 246138569Ssam } else { 247138569Ssam on->on_tx_rate2 = on->on_tx_rate2sp = 0; 248138569Ssam } 249138569Ssam if (rate > 0) { 250138569Ssam /* NB: only do this if we didn't already do it above */ 251138569Ssam on->on_tx_rate3 = rt->info[0].rateCode; 252138569Ssam on->on_tx_rate3sp = 253155477Ssam on->on_tx_rate3 | rt->info[0].shortPreamble; 254138569Ssam } else { 255138569Ssam on->on_tx_rate3 = on->on_tx_rate3sp = 0; 256138569Ssam } 257138569Ssam } else { 258138569Ssam on->on_tx_try0 = ATH_TXMAXTRY; /* max tries at rate 0 */ 259138569Ssam on->on_tx_rate1 = on->on_tx_rate1sp = 0; 260138569Ssam on->on_tx_rate2 = on->on_tx_rate2sp = 0; 261138569Ssam on->on_tx_rate3 = on->on_tx_rate3sp = 0; 262138569Ssam } 263138569Ssamdone: 264138569Ssam on->on_tx_ok = on->on_tx_err = on->on_tx_retr = on->on_tx_upper = 0; 265178354Ssam 266178354Ssam on->on_interval = ath_rateinterval; 267178354Ssam if (vap->iv_opmode == IEEE80211_M_STA) 268178354Ssam on->on_interval /= 2; 269178354Ssam on->on_interval = (on->on_interval * hz) / 1000; 270138569Ssam} 271138569Ssam 272138569Ssam/* 273138569Ssam * Set the starting transmit rate for a node. 274138569Ssam */ 275138569Ssamstatic void 276138569Ssamath_rate_ctl_start(struct ath_softc *sc, struct ieee80211_node *ni) 277138569Ssam{ 278138569Ssam#define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL) 279184347Ssam const struct ieee80211_txparam *tp = ni->ni_txparms; 280138569Ssam int srate; 281138569Ssam 282138569Ssam KASSERT(ni->ni_rates.rs_nrates > 0, ("no rates")); 283178354Ssam if (tp == NULL || tp->ucastrate == IEEE80211_FIXED_RATE_NONE) { 284138569Ssam /* 285138569Ssam * No fixed rate is requested. For 11b start with 286138569Ssam * the highest negotiated rate; otherwise, for 11g 287138569Ssam * and 11a, we start "in the middle" at 24Mb or 36Mb. 288138569Ssam */ 289138569Ssam srate = ni->ni_rates.rs_nrates - 1; 290138569Ssam if (sc->sc_curmode != IEEE80211_MODE_11B) { 291138569Ssam /* 292138569Ssam * Scan the negotiated rate set to find the 293138569Ssam * closest rate. 294138569Ssam */ 295138569Ssam /* NB: the rate set is assumed sorted */ 296138569Ssam for (; srate >= 0 && RATE(srate) > 72; srate--) 297138569Ssam ; 298138569Ssam } 299138569Ssam } else { 300138569Ssam /* 301170530Ssam * A fixed rate is to be used; ic_fixed_rate is the 302170530Ssam * IEEE code for this rate (sans basic bit). Convert this 303138569Ssam * to the index into the negotiated rate set for 304138569Ssam * the node. We know the rate is there because the 305138569Ssam * rate set is checked when the station associates. 306138569Ssam */ 307138569Ssam /* NB: the rate set is assumed sorted */ 308138569Ssam srate = ni->ni_rates.rs_nrates - 1; 309178354Ssam for (; srate >= 0 && RATE(srate) != tp->ucastrate; srate--) 310138569Ssam ; 311138569Ssam } 312170530Ssam /* 313170530Ssam * The selected rate may not be available due to races 314170530Ssam * and mode settings. Also orphaned nodes created in 315170530Ssam * adhoc mode may not have any rate set so this lookup 316170530Ssam * can fail. This is not fatal. 317170530Ssam */ 318170530Ssam ath_rate_update(sc, ni, srate < 0 ? 0 : srate); 319138569Ssam#undef RATE 320138569Ssam} 321138569Ssam 322138569Ssam/* 323138569Ssam * Examine and potentially adjust the transmit rate. 324138569Ssam */ 325138569Ssamstatic void 326138569Ssamath_rate_ctl(void *arg, struct ieee80211_node *ni) 327138569Ssam{ 328138569Ssam struct ath_softc *sc = arg; 329138569Ssam struct onoe_node *on = ATH_NODE_ONOE(ATH_NODE(ni)); 330138569Ssam struct ieee80211_rateset *rs = &ni->ni_rates; 331138569Ssam int dir = 0, nrate, enough; 332138569Ssam 333138569Ssam /* 334138569Ssam * Rate control 335138569Ssam * XXX: very primitive version. 336138569Ssam */ 337138569Ssam enough = (on->on_tx_ok + on->on_tx_err >= 10); 338138569Ssam 339138569Ssam /* no packet reached -> down */ 340138569Ssam if (on->on_tx_err > 0 && on->on_tx_ok == 0) 341138569Ssam dir = -1; 342138569Ssam 343138569Ssam /* all packets needs retry in average -> down */ 344138569Ssam if (enough && on->on_tx_ok < on->on_tx_retr) 345138569Ssam dir = -1; 346138569Ssam 347138569Ssam /* no error and less than rate_raise% of packets need retry -> up */ 348138569Ssam if (enough && on->on_tx_err == 0 && 349138569Ssam on->on_tx_retr < (on->on_tx_ok * ath_rate_raise) / 100) 350138569Ssam dir = 1; 351138569Ssam 352178354Ssam IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, 353178354Ssam "ok %d err %d retr %d upper %d dir %d", 354178354Ssam on->on_tx_ok, on->on_tx_err, on->on_tx_retr, on->on_tx_upper, dir); 355138569Ssam 356178354Ssam nrate = on->on_rix; 357138569Ssam switch (dir) { 358138569Ssam case 0: 359138569Ssam if (enough && on->on_tx_upper > 0) 360138569Ssam on->on_tx_upper--; 361138569Ssam break; 362138569Ssam case -1: 363138569Ssam if (nrate > 0) { 364138569Ssam nrate--; 365138569Ssam sc->sc_stats.ast_rate_drop++; 366138569Ssam } 367138569Ssam on->on_tx_upper = 0; 368138569Ssam break; 369138569Ssam case 1: 370138569Ssam /* raise rate if we hit rate_raise_threshold */ 371138569Ssam if (++on->on_tx_upper < ath_rate_raise_threshold) 372138569Ssam break; 373138569Ssam on->on_tx_upper = 0; 374138569Ssam if (nrate + 1 < rs->rs_nrates) { 375138569Ssam nrate++; 376138569Ssam sc->sc_stats.ast_rate_raise++; 377138569Ssam } 378138569Ssam break; 379138569Ssam } 380138569Ssam 381178354Ssam if (nrate != on->on_rix) { 382178354Ssam IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, 383178354Ssam "%s: %dM -> %dM (%d ok, %d err, %d retr)", __func__, 384178354Ssam ni->ni_txrate / 2, 385138569Ssam (rs->rs_rates[nrate] & IEEE80211_RATE_VAL) / 2, 386138569Ssam on->on_tx_ok, on->on_tx_err, on->on_tx_retr); 387138569Ssam ath_rate_update(sc, ni, nrate); 388138569Ssam } else if (enough) 389138569Ssam on->on_tx_ok = on->on_tx_err = on->on_tx_retr = 0; 390138569Ssam} 391138569Ssam 392138569Ssamstatic void 393138569Ssamath_rate_sysctlattach(struct ath_softc *sc) 394138569Ssam{ 395138569Ssam struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev); 396138569Ssam struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev); 397138569Ssam 398138569Ssam SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 399138569Ssam "rate_interval", CTLFLAG_RW, &ath_rateinterval, 0, 400138569Ssam "rate control: operation interval (ms)"); 401138569Ssam /* XXX bounds check values */ 402138569Ssam SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 403138569Ssam "rate_raise", CTLFLAG_RW, &ath_rate_raise, 0, 404138569Ssam "rate control: retry threshold to credit rate raise (%%)"); 405138569Ssam SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 406138569Ssam "rate_raise_threshold", CTLFLAG_RW, &ath_rate_raise_threshold,0, 407138569Ssam "rate control: # good periods before raising rate"); 408138569Ssam} 409138569Ssam 410238633Sadrianstatic int 411238633Sadrianath_rate_fetch_node_stats(struct ath_softc *sc, struct ath_node *an, 412238633Sadrian struct ath_rateioctl *re) 413238633Sadrian{ 414238633Sadrian 415238633Sadrian return (EINVAL); 416238633Sadrian} 417238633Sadrian 418138569Ssamstruct ath_ratectrl * 419138569Ssamath_rate_attach(struct ath_softc *sc) 420138569Ssam{ 421138569Ssam struct onoe_softc *osc; 422138569Ssam 423138569Ssam osc = malloc(sizeof(struct onoe_softc), M_DEVBUF, M_NOWAIT|M_ZERO); 424138569Ssam if (osc == NULL) 425138569Ssam return NULL; 426138569Ssam osc->arc.arc_space = sizeof(struct onoe_node); 427138569Ssam ath_rate_sysctlattach(sc); 428138569Ssam 429138569Ssam return &osc->arc; 430138569Ssam} 431138569Ssam 432138569Ssamvoid 433138569Ssamath_rate_detach(struct ath_ratectrl *arc) 434138569Ssam{ 435138569Ssam struct onoe_softc *osc = (struct onoe_softc *) arc; 436138569Ssam 437138569Ssam free(osc, M_DEVBUF); 438138569Ssam} 439