/* $NetBSD: athrate-onoe.c,v 1.15 2012/11/08 20:43:55 dyoung Exp $ */ /*- * Copyright (c) 2002-2005 Sam Leffler, Errno Consulting * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer, * without modification. * 2. Redistributions in binary form must reproduce at minimum a disclaimer * similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any * redistribution must be conditioned upon including a substantially * similar Disclaimer requirement for further binary redistribution. * 3. Neither the names of the above-listed copyright holders nor the names * of any contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * Alternatively, this software may be distributed under the terms of the * GNU General Public License ("GPL") version 2 as published by the Free * Software Foundation. * * NO WARRANTY * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF * THE POSSIBILITY OF SUCH DAMAGES. */ #include #ifdef __FreeBSD__ __FBSDID("$FreeBSD: src/sys/dev/ath/ath_rate/onoe/onoe.c,v 1.10 2005/08/09 10:19:43 rwatson Exp $"); #endif #ifdef __NetBSD__ __KERNEL_RCSID(0, "$NetBSD: athrate-onoe.c,v 1.15 2012/11/08 20:43:55 dyoung Exp $"); #endif /* * Atsushi Onoe's rate control algorithm. */ #include "opt_inet.h" #include #include #include #include #include #include #include #include #include #include #include #include /* XXX for ether_sprintf */ #include #include #ifdef INET #include #endif #include "ah_desc.h" #include #include #include #include #ifndef ONOE_DEBUG #define ONOE_DEBUG #endif #ifdef ONOE_DEBUG enum { ATH_DEBUG_RATE = 0x00000010, /* rate control */ }; #define DPRINTF(sc, _fmt, ...) do { \ if (sc->sc_debug & ATH_DEBUG_RATE) \ printf(_fmt, __VA_ARGS__); \ } while (0) #else #define DPRINTF(sc, _fmt, ...) #endif /* * Default parameters for the rate control algorithm. These are * all tunable with sysctls. The rate controller runs periodically * (each ath_rateinterval ms) analyzing transmit statistics for each * neighbor/station (when operating in station mode this is only the AP). * If transmits look to be working well over a sampling period then * it gives a "raise rate credit". If transmits look to not be working * well than it deducts a credit. If the credits cross a threshold then * the transmit rate is raised. Various error conditions force the * the transmit rate to be dropped. * * The decision to issue/deduct a credit is based on the errors and * retries accumulated over the sampling period. ath_rate_raise defines * the percent of retransmits for which a credit is issued/deducted. * ath_rate_raise_threshold defines the threshold on credits at which * the transmit rate is increased. * * XXX this algorithm is flawed. */ static int ath_rateinterval = 1000; /* rate ctl interval (ms) */ static int ath_rate_raise = 10; /* add credit threshold */ static int ath_rate_raise_threshold = 10; /* rate ctl raise threshold */ static void ath_ratectl(void *); static void ath_rate_update(struct ath_softc *, struct ieee80211_node *, int rate); static void ath_rate_ctl_start(struct ath_softc *, struct ieee80211_node *); static void ath_rate_ctl(void *, struct ieee80211_node *); void ath_rate_node_init(struct ath_softc *sc, struct ath_node *an) { /* NB: assumed to be zero'd by caller */ ath_rate_update(sc, &an->an_node, 0); } void ath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an) { } void ath_rate_findrate(struct ath_softc *sc, struct ath_node *an, int shortPreamble, size_t frameLen, u_int8_t *rix, int *try0, u_int8_t *txrate) { struct onoe_node *on = ATH_NODE_ONOE(an); *rix = on->on_tx_rix0; *try0 = on->on_tx_try0; if (shortPreamble) *txrate = on->on_tx_rate0sp; else *txrate = on->on_tx_rate0; } void ath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an, struct ath_desc *ds, int shortPreamble, u_int8_t rix) { struct onoe_node *on = ATH_NODE_ONOE(an); ath_hal_setupxtxdesc(sc->sc_ah, ds , on->on_tx_rate1sp, 2 /* series 1 */ , on->on_tx_rate2sp, 2 /* series 2 */ , on->on_tx_rate3sp, 2 /* series 3 */ ); } void ath_rate_tx_complete(struct ath_softc *sc, struct ath_node *an, const struct ath_desc *ds, const struct ath_desc *ds0) { struct onoe_node *on = ATH_NODE_ONOE(an); if (ds->ds_txstat.ts_status == 0) on->on_tx_ok++; else on->on_tx_err++; on->on_tx_retr += ds->ds_txstat.ts_shortretry + ds->ds_txstat.ts_longretry; } void ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew) { if (isnew) ath_rate_ctl_start(sc, &an->an_node); } static void ath_rate_update(struct ath_softc *sc, struct ieee80211_node *ni, int rate) { struct ath_node *an = ATH_NODE(ni); struct onoe_node *on = ATH_NODE_ONOE(an); const HAL_RATE_TABLE *rt = sc->sc_currates; u_int8_t rix; KASSERTMSG(rt != NULL, "no rate table, mode %u", sc->sc_curmode); DPRINTF(sc, "%s: set xmit rate for %s to %dM\n", __func__, ether_sprintf(ni->ni_macaddr), ni->ni_rates.rs_nrates > 0 ? (ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL) / 2 : 0); ni->ni_txrate = rate; /* * Before associating a node has no rate set setup * so we can't calculate any transmit codes to use. * This is ok since we should never be sending anything * but management frames and those always go at the * lowest hardware rate. */ if (ni->ni_rates.rs_nrates == 0) goto done; on->on_tx_rix0 = sc->sc_rixmap[ ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL]; on->on_tx_rate0 = rt->info[on->on_tx_rix0].rateCode; on->on_tx_rate0sp = on->on_tx_rate0 | rt->info[on->on_tx_rix0].shortPreamble; if (sc->sc_mrretry) { /* * Hardware supports multi-rate retry; setup two * step-down retry rates and make the lowest rate * be the ``last chance''. We use 4, 2, 2, 2 tries * respectively (4 is set here, the rest are fixed * in the xmit routine). */ on->on_tx_try0 = 1 + 3; /* 4 tries at rate 0 */ if (--rate >= 0) { rix = sc->sc_rixmap[ ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; on->on_tx_rate1 = rt->info[rix].rateCode; on->on_tx_rate1sp = on->on_tx_rate1 | rt->info[rix].shortPreamble; } else { on->on_tx_rate1 = on->on_tx_rate1sp = 0; } if (--rate >= 0) { rix = sc->sc_rixmap[ ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; on->on_tx_rate2 = rt->info[rix].rateCode; on->on_tx_rate2sp = on->on_tx_rate2 | rt->info[rix].shortPreamble; } else { on->on_tx_rate2 = on->on_tx_rate2sp = 0; } if (rate > 0) { /* NB: only do this if we didn't already do it above */ on->on_tx_rate3 = rt->info[0].rateCode; on->on_tx_rate3sp = on->on_tx_rate3 | rt->info[0].shortPreamble; } else { on->on_tx_rate3 = on->on_tx_rate3sp = 0; } } else { on->on_tx_try0 = ATH_TXMAXTRY; /* max tries at rate 0 */ on->on_tx_rate1 = on->on_tx_rate1sp = 0; on->on_tx_rate2 = on->on_tx_rate2sp = 0; on->on_tx_rate3 = on->on_tx_rate3sp = 0; } done: on->on_tx_ok = on->on_tx_err = on->on_tx_retr = on->on_tx_upper = 0; } /* * Set the starting transmit rate for a node. */ static void ath_rate_ctl_start(struct ath_softc *sc, struct ieee80211_node *ni) { #define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL) struct ieee80211com *ic = &sc->sc_ic; int srate; KASSERTMSG(ni->ni_rates.rs_nrates > 0, "no rates"); if (ic->ic_fixed_rate == IEEE80211_FIXED_RATE_NONE) { /* * No fixed rate is requested. For 11b start with * the highest negotiated rate; otherwise, for 11g * and 11a, we start "in the middle" at 24Mb or 36Mb. */ srate = ni->ni_rates.rs_nrates - 1; if (sc->sc_curmode != IEEE80211_MODE_11B) { /* * Scan the negotiated rate set to find the * closest rate. */ /* NB: the rate set is assumed sorted */ for (; srate >= 0 && RATE(srate) > 72; srate--) ; KASSERTMSG(srate >= 0, "bogus rate set"); } } else { /* * A fixed rate is to be used; ic_fixed_rate is an * index into the supported rate set. Convert this * to the index into the negotiated rate set for * the node. We know the rate is there because the * rate set is checked when the station associates. */ const struct ieee80211_rateset *rs = &ic->ic_sup_rates[ic->ic_curmode]; int r = rs->rs_rates[ic->ic_fixed_rate] & IEEE80211_RATE_VAL; /* NB: the rate set is assumed sorted */ srate = ni->ni_rates.rs_nrates - 1; for (; srate >= 0 && RATE(srate) != r; srate--) ; KASSERTMSG(srate >= 0, "fixed rate %d not in rate set", ic->ic_fixed_rate); } ath_rate_update(sc, ni, srate); #undef RATE } static void ath_rate_cb(void *arg, struct ieee80211_node *ni) { struct ath_softc *sc = arg; ath_rate_update(sc, ni, 0); } /* * Reset the rate control state for each 802.11 state transition. */ void ath_rate_newstate(struct ath_softc *sc, enum ieee80211_state state) { struct onoe_softc *osc = (struct onoe_softc *) sc->sc_rc; struct ieee80211com *ic = &sc->sc_ic; struct ieee80211_node *ni; if (state == IEEE80211_S_INIT) { callout_stop(&osc->timer); return; } if (ic->ic_opmode == IEEE80211_M_STA) { /* * Reset local xmit state; this is really only * meaningful when operating in station mode. */ ni = ic->ic_bss; if (state == IEEE80211_S_RUN) { ath_rate_ctl_start(sc, ni); } else { ath_rate_update(sc, ni, 0); } } else { /* * When operating as a station the node table holds * the AP's that were discovered during scanning. * For any other operating mode we want to reset the * tx rate state of each node. */ ieee80211_iterate_nodes(&ic->ic_sta, ath_rate_cb, sc); ath_rate_update(sc, ic->ic_bss, 0); } if (ic->ic_fixed_rate == IEEE80211_FIXED_RATE_NONE && state == IEEE80211_S_RUN) { int interval; /* * Start the background rate control thread if we * are not configured to use a fixed xmit rate. */ interval = ath_rateinterval; if (ic->ic_opmode == IEEE80211_M_STA) interval /= 2; callout_reset(&osc->timer, (interval * hz) / 1000, ath_ratectl, &sc->sc_if); } } /* * Examine and potentially adjust the transmit rate. */ static void ath_rate_ctl(void *arg, struct ieee80211_node *ni) { struct ath_softc *sc = arg; struct onoe_node *on = ATH_NODE_ONOE(ATH_NODE(ni)); struct ieee80211_rateset *rs = &ni->ni_rates; int dir = 0, nrate, enough; /* * Rate control * XXX: very primitive version. */ enough = (on->on_tx_ok + on->on_tx_err >= 10); /* no packet reached -> down */ if (on->on_tx_err > 0 && on->on_tx_ok == 0) dir = -1; /* all packets needs retry in average -> down */ if (enough && on->on_tx_ok < on->on_tx_retr) dir = -1; /* no error and less than rate_raise% of packets need retry -> up */ if (enough && on->on_tx_err == 0 && on->on_tx_retr < (on->on_tx_ok * ath_rate_raise) / 100) dir = 1; DPRINTF(sc, "%s: ok %d err %d retr %d upper %d dir %d\n", ether_sprintf(ni->ni_macaddr), on->on_tx_ok, on->on_tx_err, on->on_tx_retr, on->on_tx_upper, dir); nrate = ni->ni_txrate; switch (dir) { case 0: if (enough && on->on_tx_upper > 0) on->on_tx_upper--; break; case -1: if (nrate > 0) { nrate--; sc->sc_stats.ast_rate_drop++; } on->on_tx_upper = 0; break; case 1: /* raise rate if we hit rate_raise_threshold */ if (++on->on_tx_upper < ath_rate_raise_threshold) break; on->on_tx_upper = 0; if (nrate + 1 < rs->rs_nrates) { nrate++; sc->sc_stats.ast_rate_raise++; } break; } if (nrate != ni->ni_txrate) { DPRINTF(sc, "%s: %dM -> %dM (%d ok, %d err, %d retr)\n", __func__, (rs->rs_rates[ni->ni_txrate] & IEEE80211_RATE_VAL) / 2, (rs->rs_rates[nrate] & IEEE80211_RATE_VAL) / 2, on->on_tx_ok, on->on_tx_err, on->on_tx_retr); ath_rate_update(sc, ni, nrate); } else if (enough) on->on_tx_ok = on->on_tx_err = on->on_tx_retr = 0; } static void ath_ratectl(void *arg) { struct ifnet *ifp = arg; struct ath_softc *sc = ifp->if_softc; struct onoe_softc *osc = (struct onoe_softc *) sc->sc_rc; struct ieee80211com *ic = &sc->sc_ic; int interval; if (ifp->if_flags & IFF_RUNNING) { sc->sc_stats.ast_rate_calls++; if (ic->ic_opmode == IEEE80211_M_STA) ath_rate_ctl(sc, ic->ic_bss); /* NB: no reference */ else ieee80211_iterate_nodes(&ic->ic_sta, ath_rate_ctl, sc); } interval = ath_rateinterval; if (ic->ic_opmode == IEEE80211_M_STA) interval /= 2; callout_reset(&osc->timer, (interval * hz) / 1000, ath_ratectl, &sc->sc_if); } static void ath_rate_sysctlattach(struct ath_softc *sc) { struct sysctllog **clog = &sc->sc_sysctllog; const struct sysctlnode *cnode, *rnode; if ((rnode = ath_sysctl_treetop(NULL)) == NULL) return; SYSCTL_GLOBAL_INT(CTLFLAG_READWRITE, "rate_interval", "rate control: operation interval (ms)", rateinterval); /* XXX bounds check values */ SYSCTL_GLOBAL_INT(CTLFLAG_READWRITE, "rate_raise", "rate control: retry threshold to credit rate raise (%%)", rate_raise); SYSCTL_GLOBAL_INT(CTLFLAG_READWRITE, "rate_raise_threshold", "rate control: # good periods before raising rate", rate_raise_threshold); } struct ath_ratectrl * ath_rate_attach(struct ath_softc *sc) { struct onoe_softc *osc; osc = malloc(sizeof(struct onoe_softc), M_DEVBUF, M_NOWAIT|M_ZERO); if (osc == NULL) return NULL; osc->arc.arc_space = sizeof(struct onoe_node); callout_init(&osc->timer, 0); ath_rate_sysctlattach(sc); return &osc->arc; } void ath_rate_detach(struct ath_ratectrl *arc) { struct onoe_softc *osc = (struct onoe_softc *) arc; callout_stop(&osc->timer); free(osc, M_DEVBUF); }