/*- * Copyright (c) 2004-2005 INRIA * 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. * */ /* * AMRR rate control. See: * http://www-sop.inria.fr/rapports/sophia/RR-5208.html * "IEEE 802.11 Rate Adaptation: A Practical Approach" by * Mathieu Lacage, Hossein Manshaei, Thierry Turletti */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "if_athvar.h" #include "ah_desc.h" #include "amrr.h" #define AMRR_DEBUG #ifdef AMRR_DEBUG #define DPRINTF(sc, _fmt, ...) do { \ if (sc->sc_debug & 0x10) \ printk(_fmt, __VA_ARGS__); \ } while (0) #else #define DPRINTF(sc, _fmt, ...) #endif static int ath_rateinterval = 1000; /* rate ctl interval (ms) */ static int ath_rate_max_success_threshold = 10; static int ath_rate_min_success_threshold = 1; static void ath_ratectl(unsigned long); 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); } EXPORT_SYMBOL(ath_rate_node_init); void ath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an) { } EXPORT_SYMBOL(ath_rate_node_cleanup); 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 amrr_node *amn = ATH_NODE_AMRR(an); *rix = amn->amn_tx_rix0; *try0 = amn->amn_tx_try0; if (shortPreamble) *txrate = amn->amn_tx_rate0sp; else *txrate = amn->amn_tx_rate0; } EXPORT_SYMBOL(ath_rate_findrate); void ath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an, struct ath_desc *ds, int shortPreamble, u_int8_t rix) { struct amrr_node *amn = ATH_NODE_AMRR(an); ath_hal_setupxtxdesc(sc->sc_ah, ds , amn->amn_tx_rate1sp, amn->amn_tx_try1 /* series 1 */ , amn->amn_tx_rate2sp, amn->amn_tx_try2 /* series 2 */ , amn->amn_tx_rate3sp, amn->amn_tx_try3 /* series 3 */ ); } EXPORT_SYMBOL(ath_rate_setupxtxdesc); void ath_rate_tx_complete(struct ath_softc *sc, struct ath_node *an, const struct ath_desc *ds) { struct amrr_node *amn = ATH_NODE_AMRR(an); int sr = ds->ds_txstat.ts_shortretry; int lr = ds->ds_txstat.ts_longretry; int retry_count = sr + lr; amn->amn_tx_try0_cnt++; if (retry_count == 1) { amn->amn_tx_try1_cnt++; } else if (retry_count == 2) { amn->amn_tx_try1_cnt++; amn->amn_tx_try2_cnt++; } else if (retry_count == 3) { amn->amn_tx_try1_cnt++; amn->amn_tx_try2_cnt++; amn->amn_tx_try3_cnt++; } else if (retry_count > 3) { amn->amn_tx_try1_cnt++; amn->amn_tx_try2_cnt++; amn->amn_tx_try3_cnt++; amn->amn_tx_failure_cnt++; } } EXPORT_SYMBOL(ath_rate_tx_complete); void ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew) { if (isnew) ath_rate_ctl_start(sc, &an->an_node); } EXPORT_SYMBOL(ath_rate_newassoc); static void node_reset (struct amrr_node *amn) { amn->amn_tx_try0_cnt = 0; amn->amn_tx_try1_cnt = 0; amn->amn_tx_try2_cnt = 0; amn->amn_tx_try3_cnt = 0; amn->amn_tx_failure_cnt = 0; amn->amn_success = 0; amn->amn_recovery = 0; amn->amn_success_threshold = ath_rate_min_success_threshold; } /** * The code below assumes that we are dealing with hardware multi rate retry * I have no idea what will happen if you try to use this module with another * type of hardware. Your machine might catch fire or it might work with * horrible performance... */ static void ath_rate_update(struct ath_softc *sc, struct ieee80211_node *ni, int rate) { struct ath_node *an = ATH_NODE(ni); struct amrr_node *amn = ATH_NODE_AMRR(an); const HAL_RATE_TABLE *rt = sc->sc_currates; u_int8_t rix; KASSERT(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; /* XXX management/control frames always go at the lowest speed */ an->an_tx_mgtrate = rt->info[0].rateCode; an->an_tx_mgtratesp = an->an_tx_mgtrate | rt->info[0].shortPreamble; /* * 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) { amn->amn_tx_rix0 = sc->sc_rixmap[ ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL]; amn->amn_tx_rate0 = rt->info[amn->amn_tx_rix0].rateCode; amn->amn_tx_rate0sp = amn->amn_tx_rate0 | rt->info[amn->amn_tx_rix0].shortPreamble; if (sc->sc_mrretry) { amn->amn_tx_try0 = 1; amn->amn_tx_try1 = 1; amn->amn_tx_try2 = 1; amn->amn_tx_try3 = 1; if (--rate >= 0) { rix = sc->sc_rixmap[ ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; amn->amn_tx_rate1 = rt->info[rix].rateCode; amn->amn_tx_rate1sp = amn->amn_tx_rate1 | rt->info[rix].shortPreamble; } else { amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0; } if (--rate >= 0) { rix = sc->sc_rixmap[ ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; amn->amn_tx_rate2 = rt->info[rix].rateCode; amn->amn_tx_rate2sp = amn->amn_tx_rate2 | rt->info[rix].shortPreamble; } else { amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0; } if (rate > 0) { /* NB: only do this if we didn't already do it above */ amn->amn_tx_rate3 = rt->info[0].rateCode; amn->amn_tx_rate3sp = an->an_tx_mgtrate | rt->info[0].shortPreamble; } else { amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0; } } else { amn->amn_tx_try0 = ATH_TXMAXTRY; /* theorically, these statements are useless because * the code which uses them tests for an_tx_try0 == ATH_TXMAXTRY */ amn->amn_tx_try1 = 0; amn->amn_tx_try2 = 0; amn->amn_tx_try3 = 0; amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0; amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0; amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0; } } node_reset (amn); } /* * 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; KASSERT(ni->ni_rates.rs_nrates > 0, ("no rates")); if (ic->ic_fixed_rate == -1) { /* * 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--) ; KASSERT(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--) ; KASSERT(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 amrr_softc *asc = (struct amrr_softc *) sc->sc_rc; struct ieee80211com *ic = &sc->sc_ic; struct ieee80211_node *ni; if (state == IEEE80211_S_INIT) { del_timer(&asc->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 == -1 && 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; mod_timer(&asc->timer, jiffies + ((HZ * interval) / 1000)); } } EXPORT_SYMBOL(ath_rate_newstate); /* * Examine and potentially adjust the transmit rate. */ static void ath_rate_ctl(void *arg, struct ieee80211_node *ni) { struct ath_softc *sc = arg; struct amrr_node *amn = ATH_NODE_AMRR(ATH_NODE (ni)); int old_rate; #define is_success(amn) \ (amn->amn_tx_try1_cnt < (amn->amn_tx_try0_cnt/10)) #define is_enough(amn) \ (amn->amn_tx_try0_cnt > 10) #define is_failure(amn) \ (amn->amn_tx_try1_cnt > (amn->amn_tx_try0_cnt/3)) #define is_max_rate(ni) \ ((ni->ni_txrate + 1) >= ni->ni_rates.rs_nrates) #define is_min_rate(ni) \ (ni->ni_txrate == 0) old_rate = ni->ni_txrate; DPRINTF (sc, "cnt0: %d cnt1: %d cnt2: %d cnt3: %d -- threshold: %d\n", amn->amn_tx_try0_cnt, amn->amn_tx_try1_cnt, amn->amn_tx_try2_cnt, amn->amn_tx_try3_cnt, amn->amn_success_threshold); if (is_success (amn) && is_enough (amn)) { amn->amn_success++; if (amn->amn_success == amn->amn_success_threshold && !is_max_rate (ni)) { amn->amn_recovery = 1; amn->amn_success = 0; ni->ni_txrate++; DPRINTF (sc, "increase rate to %d\n", ni->ni_txrate); } else { amn->amn_recovery = 0; } } else if (is_failure (amn)) { amn->amn_success = 0; if (!is_min_rate (ni)) { if (amn->amn_recovery) { /* recovery failure. */ amn->amn_success_threshold *= 2; amn->amn_success_threshold = min (amn->amn_success_threshold, (u_int)ath_rate_max_success_threshold); DPRINTF (sc, "decrease rate recovery thr: %d\n", amn->amn_success_threshold); } else { /* simple failure. */ amn->amn_success_threshold = ath_rate_min_success_threshold; DPRINTF (sc, "decrease rate normal thr: %d\n", amn->amn_success_threshold); } amn->amn_recovery = 0; ni->ni_txrate--; } else { amn->amn_recovery = 0; } } if (is_enough (amn) || old_rate != ni->ni_txrate) { /* reset counters. */ amn->amn_tx_try0_cnt = 0; amn->amn_tx_try1_cnt = 0; amn->amn_tx_try2_cnt = 0; amn->amn_tx_try3_cnt = 0; amn->amn_tx_failure_cnt = 0; } if (old_rate != ni->ni_txrate) { ath_rate_update(sc, ni, ni->ni_txrate); } } static void ath_ratectl(unsigned long data) { struct net_device *dev = (struct net_device *)data; struct ath_softc *sc = dev->priv; struct amrr_softc *asc = (struct amrr_softc *) sc->sc_rc; struct ieee80211com *ic = &sc->sc_ic; int interval; if (dev->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; asc->timer.expires = jiffies + ((HZ * interval) / 1000); add_timer(&asc->timer); } struct ath_ratectrl * ath_rate_attach(struct ath_softc *sc) { struct amrr_softc *asc; asc = kmalloc(sizeof(struct amrr_softc), GFP_ATOMIC); if (asc == NULL) return NULL; asc->arc.arc_space = sizeof(struct amrr_node); init_timer(&asc->timer); asc->timer.data = (unsigned long) &sc->sc_dev; asc->timer.function = ath_ratectl; return &asc->arc; } EXPORT_SYMBOL(ath_rate_attach); void ath_rate_detach(struct ath_ratectrl *arc) { struct amrr_softc *asc = (struct amrr_softc *) arc; del_timer(&asc->timer); kfree(asc); } EXPORT_SYMBOL(ath_rate_detach); static int minrateinterval = 500; /* 500ms */ static int maxint = 0x7fffffff; /* 32-bit big */ static int min_threshold = 1; #define CTL_AUTO -2 /* cannot be CTL_ANY or CTL_NONE */ #ifdef CONFIG_SYSCTL void ath_rate_dynamic_sysctl_register(struct ath_softc *sc) { } EXPORT_SYMBOL(ath_rate_dynamic_sysctl_register); #endif /* CONFIG_SYSCTL */ /* * Static (i.e. global) sysctls. */ enum { DEV_ATH = 9, /* XXX known by many */ }; static ctl_table ath_rate_static_sysctls[] = { { .ctl_name = CTL_AUTO, .procname = "interval", .mode = 0644, .data = &ath_rateinterval, .maxlen = sizeof(ath_rateinterval), .extra1 = &minrateinterval, .extra2 = &maxint, .proc_handler = proc_dointvec_minmax }, { .ctl_name = CTL_AUTO, .procname = "max_success_threshold", .mode = 0644, .data = &ath_rate_max_success_threshold, .maxlen = sizeof(ath_rate_max_success_threshold), .extra1 = &min_threshold, .extra2 = &maxint, .proc_handler = proc_dointvec_minmax }, { .ctl_name = CTL_AUTO, .procname = "min_success_threshold", .mode = 0644, .data = &ath_rate_min_success_threshold, .maxlen = sizeof(ath_rate_min_success_threshold), .extra1 = &min_threshold, .extra2 = &maxint, .proc_handler = proc_dointvec_minmax }, { 0 } }; static ctl_table ath_rate_table[] = { { .ctl_name = CTL_AUTO, .procname = "rate", .mode = 0555, .child = ath_rate_static_sysctls }, { 0 } }; static ctl_table ath_ath_table[] = { { .ctl_name = DEV_ATH, .procname = "ath", .mode = 0555, .child = ath_rate_table }, { 0 } }; static ctl_table ath_root_table[] = { { .ctl_name = CTL_DEV, .procname = "dev", .mode = 0555, .child = ath_ath_table }, { 0 } }; static struct ctl_table_header *ath_sysctl_header; MODULE_AUTHOR("INRIA, Mathieu Lacage"); MODULE_DESCRIPTION("AMRR Rate control algorithm"); #ifdef MODULE_LICENSE MODULE_LICENSE("Dual BSD/GPL"); #endif static char *version = "0.1"; static char *dev_info = "ath_rate_amrr"; static int __init init_ath_rate_amrr(void) { printk(KERN_INFO "%s: %s\n", dev_info, version); #ifdef CONFIG_SYSCTL ath_sysctl_header = register_sysctl_table(ath_root_table, 1); #endif return (0); } module_init(init_ath_rate_amrr); static void __exit exit_ath_rate_amrr(void) { #ifdef CONFIG_SYSCTL if (ath_sysctl_header != NULL) unregister_sysctl_table(ath_sysctl_header); #endif printk(KERN_INFO "%s: unloaded\n", dev_info); } module_exit(exit_ath_rate_amrr);