/*- * Copyright (c) 2005 John Bicket * 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 __FBSDID("$FreeBSD$"); /* * John Bicket's SampleRate control algorithm. */ #include "opt_ath.h" #include "opt_inet.h" #include "opt_wlan.h" #include "opt_ah.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* XXX for ether_sprintf */ #include #include #ifdef INET #include #include #endif #include #include #include #include /* * This file is an implementation of the SampleRate algorithm * in "Bit-rate Selection in Wireless Networks" * (http://www.pdos.lcs.mit.edu/papers/jbicket-ms.ps) * * SampleRate chooses the bit-rate it predicts will provide the most * throughput based on estimates of the expected per-packet * transmission time for each bit-rate. SampleRate periodically sends * packets at bit-rates other than the current one to estimate when * another bit-rate will provide better performance. SampleRate * switches to another bit-rate when its estimated per-packet * transmission time becomes smaller than the current bit-rate's. * SampleRate reduces the number of bit-rates it must sample by * eliminating those that could not perform better than the one * currently being used. SampleRate also stops probing at a bit-rate * if it experiences several successive losses. * * The difference between the algorithm in the thesis and the one in this * file is that the one in this file uses a ewma instead of a window. * * Also, this implementation tracks the average transmission time for * a few different packet sizes independently for each link. */ static void ath_rate_ctl_reset(struct ath_softc *, struct ieee80211_node *); static __inline int size_to_bin(int size) { #if NUM_PACKET_SIZE_BINS > 1 if (size <= packet_size_bins[0]) return 0; #endif #if NUM_PACKET_SIZE_BINS > 2 if (size <= packet_size_bins[1]) return 1; #endif #if NUM_PACKET_SIZE_BINS > 3 if (size <= packet_size_bins[2]) return 2; #endif #if NUM_PACKET_SIZE_BINS > 4 #error "add support for more packet sizes" #endif return NUM_PACKET_SIZE_BINS-1; } void ath_rate_node_init(struct ath_softc *sc, struct ath_node *an) { /* NB: assumed to be zero'd by caller */ } void ath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an) { } static int dot11rate(const HAL_RATE_TABLE *rt, int rix) { if (rix < 0) return -1; return rt->info[rix].phy == IEEE80211_T_HT ? rt->info[rix].dot11Rate : (rt->info[rix].dot11Rate & IEEE80211_RATE_VAL) / 2; } static const char * dot11rate_label(const HAL_RATE_TABLE *rt, int rix) { if (rix < 0) return ""; return rt->info[rix].phy == IEEE80211_T_HT ? "MCS" : "Mb "; } /* * Return the rix with the lowest average_tx_time, * or -1 if all the average_tx_times are 0. */ static __inline int pick_best_rate(struct ath_node *an, const HAL_RATE_TABLE *rt, int size_bin, int require_acked_before) { struct sample_node *sn = ATH_NODE_SAMPLE(an); int best_rate_rix, best_rate_tt, best_rate_pct; uint64_t mask; int rix, tt, pct; best_rate_rix = 0; best_rate_tt = 0; best_rate_pct = 0; for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) { if ((mask & 1) == 0) /* not a supported rate */ continue; /* Don't pick a non-HT rate for a HT node */ if ((an->an_node.ni_flags & IEEE80211_NODE_HT) && (rt->info[rix].phy != IEEE80211_T_HT)) { continue; } tt = sn->stats[size_bin][rix].average_tx_time; if (tt <= 0 || (require_acked_before && !sn->stats[size_bin][rix].packets_acked)) continue; /* Calculate percentage if possible */ if (sn->stats[size_bin][rix].total_packets > 0) { pct = sn->stats[size_bin][rix].ewma_pct; } else { /* XXX for now, assume 95% ok */ pct = 95; } /* don't use a bit-rate that has been failing */ if (sn->stats[size_bin][rix].successive_failures > 3) continue; /* * For HT, Don't use a bit rate that is much more * lossy than the best. * * XXX this isn't optimal; it's just designed to * eliminate rates that are going to be obviously * worse. */ if (an->an_node.ni_flags & IEEE80211_NODE_HT) { if (best_rate_pct > (pct + 50)) continue; } /* * For non-MCS rates, use the current average txtime for * comparison. */ if (! (an->an_node.ni_flags & IEEE80211_NODE_HT)) { if (best_rate_tt == 0 || tt <= best_rate_tt) { best_rate_tt = tt; best_rate_rix = rix; best_rate_pct = pct; } } /* * Since 2 stream rates have slightly higher TX times, * allow a little bit of leeway. This should later * be abstracted out and properly handled. */ if (an->an_node.ni_flags & IEEE80211_NODE_HT) { if (best_rate_tt == 0 || (tt * 8 <= best_rate_tt * 10)) { best_rate_tt = tt; best_rate_rix = rix; best_rate_pct = pct; } } } return (best_rate_tt ? best_rate_rix : -1); } /* * Pick a good "random" bit-rate to sample other than the current one. */ static __inline int pick_sample_rate(struct sample_softc *ssc , struct ath_node *an, const HAL_RATE_TABLE *rt, int size_bin) { #define DOT11RATE(ix) (rt->info[ix].dot11Rate & IEEE80211_RATE_VAL) #define MCS(ix) (rt->info[ix].dot11Rate | IEEE80211_RATE_MCS) struct sample_node *sn = ATH_NODE_SAMPLE(an); int current_rix, rix; unsigned current_tt; uint64_t mask; current_rix = sn->current_rix[size_bin]; if (current_rix < 0) { /* no successes yet, send at the lowest bit-rate */ /* XXX should return MCS0 if HT */ return 0; } current_tt = sn->stats[size_bin][current_rix].average_tx_time; rix = sn->last_sample_rix[size_bin]+1; /* next sample rate */ mask = sn->ratemask &~ ((uint64_t) 1<= rt->rateCount) rix = 0; continue; } /* * The following code stops trying to sample * non-MCS rates when speaking to an MCS node. * However, at least for CCK rates in 2.4GHz mode, * the non-MCS rates MAY actually provide better * PER at the very far edge of reception. * * However! Until ath_rate_form_aggr() grows * some logic to not form aggregates if the * selected rate is non-MCS, this won't work. * * So don't disable this code until you've taught * ath_rate_form_aggr() to drop out if any of * the selected rates are non-MCS. */ #if 1 /* if the node is HT and the rate isn't HT, don't bother sample */ if ((an->an_node.ni_flags & IEEE80211_NODE_HT) && (rt->info[rix].phy != IEEE80211_T_HT)) { mask &= ~((uint64_t) 1<stats[size_bin][rix].perfect_tx_time > current_tt) { mask &= ~((uint64_t) 1<stats[size_bin][rix].successive_failures > ssc->max_successive_failures && ticks - sn->stats[size_bin][rix].last_tx < ssc->stale_failure_timeout) { mask &= ~((uint64_t) 1<an_node.ni_flags & IEEE80211_NODE_HT) { if (rix < (current_rix - 3) || rix > (current_rix + 3)) { mask &= ~((uint64_t) 1< 11M for non-HT rates */ if (! (an->an_node.ni_flags & IEEE80211_NODE_HT)) { if (DOT11RATE(rix) > 2*11 && rix > current_rix + 2) { mask &= ~((uint64_t) 1<last_sample_rix[size_bin] = rix; return rix; } return current_rix; #undef DOT11RATE #undef MCS } static int ath_rate_get_static_rix(struct ath_softc *sc, const struct ieee80211_node *ni) { #define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL) #define DOT11RATE(_ix) (rt->info[(_ix)].dot11Rate & IEEE80211_RATE_VAL) #define MCS(_ix) (ni->ni_htrates.rs_rates[_ix] | IEEE80211_RATE_MCS) const struct ieee80211_txparam *tp = ni->ni_txparms; int srate; /* Check MCS rates */ for (srate = ni->ni_htrates.rs_nrates - 1; srate >= 0; srate--) { if (MCS(srate) == tp->ucastrate) return sc->sc_rixmap[tp->ucastrate]; } /* Check legacy rates */ for (srate = ni->ni_rates.rs_nrates - 1; srate >= 0; srate--) { if (RATE(srate) == tp->ucastrate) return sc->sc_rixmap[tp->ucastrate]; } return -1; #undef RATE #undef DOT11RATE #undef MCS } static void ath_rate_update_static_rix(struct ath_softc *sc, struct ieee80211_node *ni) { struct ath_node *an = ATH_NODE(ni); const struct ieee80211_txparam *tp = ni->ni_txparms; struct sample_node *sn = ATH_NODE_SAMPLE(an); if (tp != NULL && tp->ucastrate != IEEE80211_FIXED_RATE_NONE) { /* * A fixed rate is to be used; ucastrate is the IEEE code * for this rate (sans basic bit). Check this against the * negotiated rate set for the node. Note the fixed rate * may not be available for various reasons so we only * setup the static rate index if the lookup is successful. */ sn->static_rix = ath_rate_get_static_rix(sc, ni); } else { sn->static_rix = -1; } } /* * Pick a non-HT rate to begin using. */ static int ath_rate_pick_seed_rate_legacy(struct ath_softc *sc, struct ath_node *an, int frameLen) { #define DOT11RATE(ix) (rt->info[ix].dot11Rate & IEEE80211_RATE_VAL) #define MCS(ix) (rt->info[ix].dot11Rate | IEEE80211_RATE_MCS) #define RATE(ix) (DOT11RATE(ix) / 2) int rix = -1; const HAL_RATE_TABLE *rt = sc->sc_currates; struct sample_node *sn = ATH_NODE_SAMPLE(an); const int size_bin = size_to_bin(frameLen); /* no packet has been sent successfully yet */ for (rix = rt->rateCount-1; rix > 0; rix--) { if ((sn->ratemask & ((uint64_t) 1<info[rix].phy == IEEE80211_T_HT) continue; /* * Pick the highest rate <= 36 Mbps * that hasn't failed. */ if (DOT11RATE(rix) <= 72 && sn->stats[size_bin][rix].successive_failures == 0) { break; } } return rix; #undef RATE #undef MCS #undef DOT11RATE } /* * Pick a HT rate to begin using. * * Don't use any non-HT rates; only consider HT rates. */ static int ath_rate_pick_seed_rate_ht(struct ath_softc *sc, struct ath_node *an, int frameLen) { #define DOT11RATE(ix) (rt->info[ix].dot11Rate & IEEE80211_RATE_VAL) #define MCS(ix) (rt->info[ix].dot11Rate | IEEE80211_RATE_MCS) #define RATE(ix) (DOT11RATE(ix) / 2) int rix = -1, ht_rix = -1; const HAL_RATE_TABLE *rt = sc->sc_currates; struct sample_node *sn = ATH_NODE_SAMPLE(an); const int size_bin = size_to_bin(frameLen); /* no packet has been sent successfully yet */ for (rix = rt->rateCount-1; rix > 0; rix--) { /* Skip rates we can't use */ if ((sn->ratemask & ((uint64_t) 1<info[rix].phy == IEEE80211_T_HT) ht_rix = rix; /* Skip non-HT rates */ if (rt->info[rix].phy != IEEE80211_T_HT) continue; /* * Pick a medium-speed rate regardless of stream count * which has not seen any failures. Higher rates may fail; * we'll try them later. */ if (((MCS(rix) & 0x7) <= 4) && sn->stats[size_bin][rix].successive_failures == 0) { break; } } /* * If all the MCS rates have successive failures, rix should be * > 0; otherwise use the lowest MCS rix (hopefully MCS 0.) */ return MAX(rix, ht_rix); #undef RATE #undef MCS #undef DOT11RATE } void ath_rate_findrate(struct ath_softc *sc, struct ath_node *an, int shortPreamble, size_t frameLen, u_int8_t *rix0, int *try0, u_int8_t *txrate) { #define DOT11RATE(ix) (rt->info[ix].dot11Rate & IEEE80211_RATE_VAL) #define MCS(ix) (rt->info[ix].dot11Rate | IEEE80211_RATE_MCS) #define RATE(ix) (DOT11RATE(ix) / 2) struct sample_node *sn = ATH_NODE_SAMPLE(an); struct sample_softc *ssc = ATH_SOFTC_SAMPLE(sc); struct ieee80211com *ic = &sc->sc_ic; const HAL_RATE_TABLE *rt = sc->sc_currates; const int size_bin = size_to_bin(frameLen); int rix, mrr, best_rix, change_rates; unsigned average_tx_time; ath_rate_update_static_rix(sc, &an->an_node); if (sn->currates != sc->sc_currates) { device_printf(sc->sc_dev, "%s: currates != sc_currates!\n", __func__); rix = 0; *try0 = ATH_TXMAXTRY; goto done; } if (sn->static_rix != -1) { rix = sn->static_rix; *try0 = ATH_TXMAXTRY; goto done; } mrr = sc->sc_mrretry; /* XXX check HT protmode too */ if (mrr && (ic->ic_flags & IEEE80211_F_USEPROT && !sc->sc_mrrprot)) mrr = 0; best_rix = pick_best_rate(an, rt, size_bin, !mrr); if (best_rix >= 0) { average_tx_time = sn->stats[size_bin][best_rix].average_tx_time; } else { average_tx_time = 0; } /* * Limit the time measuring the performance of other tx * rates to sample_rate% of the total transmission time. */ if (sn->sample_tt[size_bin] < average_tx_time * (sn->packets_since_sample[size_bin]*ssc->sample_rate/100)) { rix = pick_sample_rate(ssc, an, rt, size_bin); IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, &an->an_node, "att %d sample_tt %d size %u sample rate %d %s current rate %d %s", average_tx_time, sn->sample_tt[size_bin], bin_to_size(size_bin), dot11rate(rt, rix), dot11rate_label(rt, rix), dot11rate(rt, sn->current_rix[size_bin]), dot11rate_label(rt, sn->current_rix[size_bin])); if (rix != sn->current_rix[size_bin]) { sn->current_sample_rix[size_bin] = rix; } else { sn->current_sample_rix[size_bin] = -1; } sn->packets_since_sample[size_bin] = 0; } else { change_rates = 0; if (!sn->packets_sent[size_bin] || best_rix == -1) { /* no packet has been sent successfully yet */ change_rates = 1; if (an->an_node.ni_flags & IEEE80211_NODE_HT) best_rix = ath_rate_pick_seed_rate_ht(sc, an, frameLen); else best_rix = ath_rate_pick_seed_rate_legacy(sc, an, frameLen); } else if (sn->packets_sent[size_bin] < 20) { /* let the bit-rate switch quickly during the first few packets */ IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, &an->an_node, "%s: switching quickly..", __func__); change_rates = 1; } else if (ticks - ssc->min_switch > sn->ticks_since_switch[size_bin]) { /* min_switch seconds have gone by */ IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, &an->an_node, "%s: min_switch %d > ticks_since_switch %d..", __func__, ticks - ssc->min_switch, sn->ticks_since_switch[size_bin]); change_rates = 1; } else if ((! (an->an_node.ni_flags & IEEE80211_NODE_HT)) && (2*average_tx_time < sn->stats[size_bin][sn->current_rix[size_bin]].average_tx_time)) { /* the current bit-rate is twice as slow as the best one */ IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, &an->an_node, "%s: 2x att (= %d) < cur_rix att %d", __func__, 2 * average_tx_time, sn->stats[size_bin][sn->current_rix[size_bin]].average_tx_time); change_rates = 1; } else if ((an->an_node.ni_flags & IEEE80211_NODE_HT)) { int cur_rix = sn->current_rix[size_bin]; int cur_att = sn->stats[size_bin][cur_rix].average_tx_time; /* * If the node is HT, upgrade it if the MCS rate is * higher and the average tx time is within 20% of * the current rate. It can fail a little. * * This is likely not optimal! */ #if 0 printf("cur rix/att %x/%d, best rix/att %x/%d\n", MCS(cur_rix), cur_att, MCS(best_rix), average_tx_time); #endif if ((MCS(best_rix) > MCS(cur_rix)) && (average_tx_time * 8) <= (cur_att * 10)) { IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, &an->an_node, "%s: HT: best_rix 0x%d > cur_rix 0x%x, average_tx_time %d, cur_att %d", __func__, MCS(best_rix), MCS(cur_rix), average_tx_time, cur_att); change_rates = 1; } } sn->packets_since_sample[size_bin]++; if (change_rates) { if (best_rix != sn->current_rix[size_bin]) { IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, &an->an_node, "%s: size %d switch rate %d (%d/%d) -> %d (%d/%d) after %d packets mrr %d", __func__, bin_to_size(size_bin), RATE(sn->current_rix[size_bin]), sn->stats[size_bin][sn->current_rix[size_bin]].average_tx_time, sn->stats[size_bin][sn->current_rix[size_bin]].perfect_tx_time, RATE(best_rix), sn->stats[size_bin][best_rix].average_tx_time, sn->stats[size_bin][best_rix].perfect_tx_time, sn->packets_since_switch[size_bin], mrr); } sn->packets_since_switch[size_bin] = 0; sn->current_rix[size_bin] = best_rix; sn->ticks_since_switch[size_bin] = ticks; /* * Set the visible txrate for this node. */ an->an_node.ni_txrate = (rt->info[best_rix].phy == IEEE80211_T_HT) ? MCS(best_rix) : DOT11RATE(best_rix); } rix = sn->current_rix[size_bin]; sn->packets_since_switch[size_bin]++; } *try0 = mrr ? sn->sched[rix].t0 : ATH_TXMAXTRY; done: /* * This bug totally sucks and should be fixed. * * For now though, let's not panic, so we can start to figure * out how to better reproduce it. */ if (rix < 0 || rix >= rt->rateCount) { printf("%s: ERROR: rix %d out of bounds (rateCount=%d)\n", __func__, rix, rt->rateCount); rix = 0; /* XXX just default for now */ } KASSERT(rix >= 0 && rix < rt->rateCount, ("rix is %d", rix)); *rix0 = rix; *txrate = rt->info[rix].rateCode | (shortPreamble ? rt->info[rix].shortPreamble : 0); sn->packets_sent[size_bin]++; #undef DOT11RATE #undef MCS #undef RATE } /* * Get the TX rates. Don't fiddle with short preamble flags for them; * the caller can do that. */ void ath_rate_getxtxrates(struct ath_softc *sc, struct ath_node *an, uint8_t rix0, struct ath_rc_series *rc) { struct sample_node *sn = ATH_NODE_SAMPLE(an); const struct txschedule *sched = &sn->sched[rix0]; KASSERT(rix0 == sched->r0, ("rix0 (%x) != sched->r0 (%x)!\n", rix0, sched->r0)); rc[0].flags = rc[1].flags = rc[2].flags = rc[3].flags = 0; rc[0].rix = sched->r0; rc[1].rix = sched->r1; rc[2].rix = sched->r2; rc[3].rix = sched->r3; rc[0].tries = sched->t0; rc[1].tries = sched->t1; rc[2].tries = sched->t2; rc[3].tries = sched->t3; } void ath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an, struct ath_desc *ds, int shortPreamble, u_int8_t rix) { struct sample_node *sn = ATH_NODE_SAMPLE(an); const struct txschedule *sched = &sn->sched[rix]; const HAL_RATE_TABLE *rt = sc->sc_currates; uint8_t rix1, s1code, rix2, s2code, rix3, s3code; /* XXX precalculate short preamble tables */ rix1 = sched->r1; s1code = rt->info[rix1].rateCode | (shortPreamble ? rt->info[rix1].shortPreamble : 0); rix2 = sched->r2; s2code = rt->info[rix2].rateCode | (shortPreamble ? rt->info[rix2].shortPreamble : 0); rix3 = sched->r3; s3code = rt->info[rix3].rateCode | (shortPreamble ? rt->info[rix3].shortPreamble : 0); ath_hal_setupxtxdesc(sc->sc_ah, ds, s1code, sched->t1, /* series 1 */ s2code, sched->t2, /* series 2 */ s3code, sched->t3); /* series 3 */ } static void update_stats(struct ath_softc *sc, struct ath_node *an, int frame_size, int rix0, int tries0, int rix1, int tries1, int rix2, int tries2, int rix3, int tries3, int short_tries, int tries, int status, int nframes, int nbad) { struct sample_node *sn = ATH_NODE_SAMPLE(an); struct sample_softc *ssc = ATH_SOFTC_SAMPLE(sc); #ifdef IEEE80211_DEBUG const HAL_RATE_TABLE *rt = sc->sc_currates; #endif const int size_bin = size_to_bin(frame_size); const int size = bin_to_size(size_bin); int tt, tries_so_far; int is_ht40 = (an->an_node.ni_chw == 40); int pct; if (!IS_RATE_DEFINED(sn, rix0)) return; tt = calc_usecs_unicast_packet(sc, size, rix0, short_tries, MIN(tries0, tries) - 1, is_ht40); tries_so_far = tries0; if (tries1 && tries_so_far < tries) { if (!IS_RATE_DEFINED(sn, rix1)) return; tt += calc_usecs_unicast_packet(sc, size, rix1, short_tries, MIN(tries1 + tries_so_far, tries) - tries_so_far - 1, is_ht40); tries_so_far += tries1; } if (tries2 && tries_so_far < tries) { if (!IS_RATE_DEFINED(sn, rix2)) return; tt += calc_usecs_unicast_packet(sc, size, rix2, short_tries, MIN(tries2 + tries_so_far, tries) - tries_so_far - 1, is_ht40); tries_so_far += tries2; } if (tries3 && tries_so_far < tries) { if (!IS_RATE_DEFINED(sn, rix3)) return; tt += calc_usecs_unicast_packet(sc, size, rix3, short_tries, MIN(tries3 + tries_so_far, tries) - tries_so_far - 1, is_ht40); } if (sn->stats[size_bin][rix0].total_packets < ssc->smoothing_minpackets) { /* just average the first few packets */ int avg_tx = sn->stats[size_bin][rix0].average_tx_time; int packets = sn->stats[size_bin][rix0].total_packets; sn->stats[size_bin][rix0].average_tx_time = (tt+(avg_tx*packets))/(packets+nframes); } else { /* use a ewma */ sn->stats[size_bin][rix0].average_tx_time = ((sn->stats[size_bin][rix0].average_tx_time * ssc->smoothing_rate) + (tt * (100 - ssc->smoothing_rate))) / 100; } /* * XXX Don't mark the higher bit rates as also having failed; as this * unfortunately stops those rates from being tasted when trying to * TX. This happens with 11n aggregation. */ if (nframes == nbad) { #if 0 int y; #endif sn->stats[size_bin][rix0].successive_failures += nbad; #if 0 for (y = size_bin+1; y < NUM_PACKET_SIZE_BINS; y++) { /* * Also say larger packets failed since we * assume if a small packet fails at a * bit-rate then a larger one will also. */ sn->stats[y][rix0].successive_failures += nbad; sn->stats[y][rix0].last_tx = ticks; sn->stats[y][rix0].tries += tries; sn->stats[y][rix0].total_packets += nframes; } #endif } else { sn->stats[size_bin][rix0].packets_acked += (nframes - nbad); sn->stats[size_bin][rix0].successive_failures = 0; } sn->stats[size_bin][rix0].tries += tries; sn->stats[size_bin][rix0].last_tx = ticks; sn->stats[size_bin][rix0].total_packets += nframes; /* update EWMA for this rix */ /* Calculate percentage based on current rate */ if (nframes == 0) nframes = nbad = 1; pct = ((nframes - nbad) * 1000) / nframes; if (sn->stats[size_bin][rix0].total_packets < ssc->smoothing_minpackets) { /* just average the first few packets */ int a_pct = (sn->stats[size_bin][rix0].packets_acked * 1000) / (sn->stats[size_bin][rix0].total_packets); sn->stats[size_bin][rix0].ewma_pct = a_pct; } else { /* use a ewma */ sn->stats[size_bin][rix0].ewma_pct = ((sn->stats[size_bin][rix0].ewma_pct * ssc->smoothing_rate) + (pct * (100 - ssc->smoothing_rate))) / 100; } if (rix0 == sn->current_sample_rix[size_bin]) { IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, &an->an_node, "%s: size %d %s sample rate %d %s tries (%d/%d) tt %d avg_tt (%d/%d) nfrm %d nbad %d", __func__, size, status ? "FAIL" : "OK", dot11rate(rt, rix0), dot11rate_label(rt, rix0), short_tries, tries, tt, sn->stats[size_bin][rix0].average_tx_time, sn->stats[size_bin][rix0].perfect_tx_time, nframes, nbad); sn->sample_tt[size_bin] = tt; sn->current_sample_rix[size_bin] = -1; } } static void badrate(struct ath_softc *sc, int series, int hwrate, int tries, int status) { device_printf(sc->sc_dev, "bad series%d hwrate 0x%x, tries %u ts_status 0x%x\n", series, hwrate, tries, status); } void ath_rate_tx_complete(struct ath_softc *sc, struct ath_node *an, const struct ath_rc_series *rc, const struct ath_tx_status *ts, int frame_size, int nframes, int nbad) { struct ieee80211com *ic = &sc->sc_ic; struct sample_node *sn = ATH_NODE_SAMPLE(an); int final_rix, short_tries, long_tries; const HAL_RATE_TABLE *rt = sc->sc_currates; int status = ts->ts_status; int mrr; final_rix = rt->rateCodeToIndex[ts->ts_rate]; short_tries = ts->ts_shortretry; long_tries = ts->ts_longretry + 1; if (nframes == 0) { device_printf(sc->sc_dev, "%s: nframes=0?\n", __func__); return; } if (frame_size == 0) /* NB: should not happen */ frame_size = 1500; if (sn->ratemask == 0) { IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, &an->an_node, "%s: size %d %s rate/try %d/%d no rates yet", __func__, bin_to_size(size_to_bin(frame_size)), status ? "FAIL" : "OK", short_tries, long_tries); return; } mrr = sc->sc_mrretry; /* XXX check HT protmode too */ if (mrr && (ic->ic_flags & IEEE80211_F_USEPROT && !sc->sc_mrrprot)) mrr = 0; if (!mrr || ts->ts_finaltsi == 0) { if (!IS_RATE_DEFINED(sn, final_rix)) { device_printf(sc->sc_dev, "%s: ts_rate=%d ts_finaltsi=%d, final_rix=%d\n", __func__, ts->ts_rate, ts->ts_finaltsi, final_rix); badrate(sc, 0, ts->ts_rate, long_tries, status); return; } /* * Only one rate was used; optimize work. */ IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, &an->an_node, "%s: size %d (%d bytes) %s rate/short/long %d %s/%d/%d nframes/nbad [%d/%d]", __func__, bin_to_size(size_to_bin(frame_size)), frame_size, status ? "FAIL" : "OK", dot11rate(rt, final_rix), dot11rate_label(rt, final_rix), short_tries, long_tries, nframes, nbad); update_stats(sc, an, frame_size, final_rix, long_tries, 0, 0, 0, 0, 0, 0, short_tries, long_tries, status, nframes, nbad); } else { int finalTSIdx = ts->ts_finaltsi; int i; /* * Process intermediate rates that failed. */ IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, &an->an_node, "%s: size %d (%d bytes) finaltsidx %d short %d long %d %s rate/try [%d %s/%d %d %s/%d %d %s/%d %d %s/%d] nframes/nbad [%d/%d]", __func__, bin_to_size(size_to_bin(frame_size)), frame_size, finalTSIdx, short_tries, long_tries, status ? "FAIL" : "OK", dot11rate(rt, rc[0].rix), dot11rate_label(rt, rc[0].rix), rc[0].tries, dot11rate(rt, rc[1].rix), dot11rate_label(rt, rc[1].rix), rc[1].tries, dot11rate(rt, rc[2].rix), dot11rate_label(rt, rc[2].rix), rc[2].tries, dot11rate(rt, rc[3].rix), dot11rate_label(rt, rc[3].rix), rc[3].tries, nframes, nbad); for (i = 0; i < 4; i++) { if (rc[i].tries && !IS_RATE_DEFINED(sn, rc[i].rix)) badrate(sc, 0, rc[i].ratecode, rc[i].tries, status); } /* * NB: series > 0 are not penalized for failure * based on the try counts under the assumption * that losses are often bursty and since we * sample higher rates 1 try at a time doing so * may unfairly penalize them. */ if (rc[0].tries) { update_stats(sc, an, frame_size, rc[0].rix, rc[0].tries, rc[1].rix, rc[1].tries, rc[2].rix, rc[2].tries, rc[3].rix, rc[3].tries, short_tries, long_tries, long_tries > rc[0].tries, nframes, nbad); long_tries -= rc[0].tries; } if (rc[1].tries && finalTSIdx > 0) { update_stats(sc, an, frame_size, rc[1].rix, rc[1].tries, rc[2].rix, rc[2].tries, rc[3].rix, rc[3].tries, 0, 0, short_tries, long_tries, status, nframes, nbad); long_tries -= rc[1].tries; } if (rc[2].tries && finalTSIdx > 1) { update_stats(sc, an, frame_size, rc[2].rix, rc[2].tries, rc[3].rix, rc[3].tries, 0, 0, 0, 0, short_tries, long_tries, status, nframes, nbad); long_tries -= rc[2].tries; } if (rc[3].tries && finalTSIdx > 2) { update_stats(sc, an, frame_size, rc[3].rix, rc[3].tries, 0, 0, 0, 0, 0, 0, short_tries, long_tries, status, nframes, nbad); } } } void ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew) { if (isnew) ath_rate_ctl_reset(sc, &an->an_node); } static const struct txschedule *mrr_schedules[IEEE80211_MODE_MAX+2] = { NULL, /* IEEE80211_MODE_AUTO */ series_11a, /* IEEE80211_MODE_11A */ series_11g, /* IEEE80211_MODE_11B */ series_11g, /* IEEE80211_MODE_11G */ NULL, /* IEEE80211_MODE_FH */ series_11a, /* IEEE80211_MODE_TURBO_A */ series_11g, /* IEEE80211_MODE_TURBO_G */ series_11a, /* IEEE80211_MODE_STURBO_A */ series_11na, /* IEEE80211_MODE_11NA */ series_11ng, /* IEEE80211_MODE_11NG */ series_half, /* IEEE80211_MODE_HALF */ series_quarter, /* IEEE80211_MODE_QUARTER */ }; /* * Initialize the tables for a node. */ static void ath_rate_ctl_reset(struct ath_softc *sc, struct ieee80211_node *ni) { #define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL) #define DOT11RATE(_ix) (rt->info[(_ix)].dot11Rate & IEEE80211_RATE_VAL) #define MCS(_ix) (ni->ni_htrates.rs_rates[_ix] | IEEE80211_RATE_MCS) struct ath_node *an = ATH_NODE(ni); struct sample_node *sn = ATH_NODE_SAMPLE(an); const HAL_RATE_TABLE *rt = sc->sc_currates; int x, y, rix; KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode)); KASSERT(sc->sc_curmode < IEEE80211_MODE_MAX+2, ("curmode %u", sc->sc_curmode)); sn->sched = mrr_schedules[sc->sc_curmode]; KASSERT(sn->sched != NULL, ("no mrr schedule for mode %u", sc->sc_curmode)); sn->static_rix = -1; ath_rate_update_static_rix(sc, ni); sn->currates = sc->sc_currates; /* * Construct a bitmask of usable rates. This has all * negotiated rates minus those marked by the hal as * to be ignored for doing rate control. */ sn->ratemask = 0; /* MCS rates */ if (ni->ni_flags & IEEE80211_NODE_HT) { for (x = 0; x < ni->ni_htrates.rs_nrates; x++) { rix = sc->sc_rixmap[MCS(x)]; if (rix == 0xff) continue; /* skip rates marked broken by hal */ if (!rt->info[rix].valid) continue; KASSERT(rix < SAMPLE_MAXRATES, ("mcs %u has rix %d", MCS(x), rix)); sn->ratemask |= (uint64_t) 1<ni_rates.rs_nrates; x++) { rix = sc->sc_rixmap[RATE(x)]; if (rix == 0xff) continue; /* skip rates marked broken by hal */ if (!rt->info[rix].valid) continue; KASSERT(rix < SAMPLE_MAXRATES, ("rate %u has rix %d", RATE(x), rix)); sn->ratemask |= (uint64_t) 1<ni_vap, IEEE80211_MSG_RATECTL)) { uint64_t mask; ieee80211_note(ni->ni_vap, "[%6D] %s: size 1600 rate/tt", ni->ni_macaddr, ":", __func__); for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) { if ((mask & 1) == 0) continue; printf(" %d %s/%d", dot11rate(rt, rix), dot11rate_label(rt, rix), calc_usecs_unicast_packet(sc, 1600, rix, 0,0, (ni->ni_chw == 40))); } printf("\n"); } #endif for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) { int size = bin_to_size(y); uint64_t mask; sn->packets_sent[y] = 0; sn->current_sample_rix[y] = -1; sn->last_sample_rix[y] = 0; /* XXX start with first valid rate */ sn->current_rix[y] = ffs(sn->ratemask)-1; /* * Initialize the statistics buckets; these are * indexed by the rate code index. */ for (rix = 0, mask = sn->ratemask; mask != 0; rix++, mask >>= 1) { if ((mask & 1) == 0) /* not a valid rate */ continue; sn->stats[y][rix].successive_failures = 0; sn->stats[y][rix].tries = 0; sn->stats[y][rix].total_packets = 0; sn->stats[y][rix].packets_acked = 0; sn->stats[y][rix].last_tx = 0; sn->stats[y][rix].ewma_pct = 0; sn->stats[y][rix].perfect_tx_time = calc_usecs_unicast_packet(sc, size, rix, 0, 0, (ni->ni_chw == 40)); sn->stats[y][rix].average_tx_time = sn->stats[y][rix].perfect_tx_time; } } #if 0 /* XXX 0, num_rates-1 are wrong */ IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, "%s: %d rates %d%sMbps (%dus)- %d%sMbps (%dus)", __func__, sn->num_rates, DOT11RATE(0)/2, DOT11RATE(0) % 1 ? ".5" : "", sn->stats[1][0].perfect_tx_time, DOT11RATE(sn->num_rates-1)/2, DOT11RATE(sn->num_rates-1) % 1 ? ".5" : "", sn->stats[1][sn->num_rates-1].perfect_tx_time ); #endif /* set the visible bit-rate */ if (sn->static_rix != -1) ni->ni_txrate = DOT11RATE(sn->static_rix); else ni->ni_txrate = RATE(0); #undef RATE #undef DOT11RATE } /* * Fetch the statistics for the given node. * * The ieee80211 node must be referenced and unlocked, however the ath_node * must be locked. * * The main difference here is that we convert the rate indexes * to 802.11 rates, or the userland output won't make much sense * as it has no access to the rix table. */ int ath_rate_fetch_node_stats(struct ath_softc *sc, struct ath_node *an, struct ath_rateioctl *rs) { struct sample_node *sn = ATH_NODE_SAMPLE(an); const HAL_RATE_TABLE *rt = sc->sc_currates; struct ath_rateioctl_tlv av; struct ath_rateioctl_rt *tv; int y; int o = 0; ATH_NODE_LOCK_ASSERT(an); /* * Ensure there's enough space for the statistics. */ if (rs->len < sizeof(struct ath_rateioctl_tlv) + sizeof(struct ath_rateioctl_rt) + sizeof(struct ath_rateioctl_tlv) + sizeof(struct sample_node)) { device_printf(sc->sc_dev, "%s: len=%d, too short\n", __func__, rs->len); return (EINVAL); } /* * Take a temporary copy of the sample node state so we can * modify it before we copy it. */ tv = malloc(sizeof(struct ath_rateioctl_rt), M_TEMP, M_NOWAIT | M_ZERO); if (tv == NULL) { return (ENOMEM); } /* * Populate the rate table mapping TLV. */ tv->nentries = rt->rateCount; for (y = 0; y < rt->rateCount; y++) { tv->ratecode[y] = rt->info[y].dot11Rate & IEEE80211_RATE_VAL; if (rt->info[y].phy == IEEE80211_T_HT) tv->ratecode[y] |= IEEE80211_RATE_MCS; } o = 0; /* * First TLV - rate code mapping */ av.tlv_id = ATH_RATE_TLV_RATETABLE; av.tlv_len = sizeof(struct ath_rateioctl_rt); copyout(&av, rs->buf + o, sizeof(struct ath_rateioctl_tlv)); o += sizeof(struct ath_rateioctl_tlv); copyout(tv, rs->buf + o, sizeof(struct ath_rateioctl_rt)); o += sizeof(struct ath_rateioctl_rt); /* * Second TLV - sample node statistics */ av.tlv_id = ATH_RATE_TLV_SAMPLENODE; av.tlv_len = sizeof(struct sample_node); copyout(&av, rs->buf + o, sizeof(struct ath_rateioctl_tlv)); o += sizeof(struct ath_rateioctl_tlv); /* * Copy the statistics over to the provided buffer. */ copyout(sn, rs->buf + o, sizeof(struct sample_node)); o += sizeof(struct sample_node); free(tv, M_TEMP); return (0); } static void sample_stats(void *arg, struct ieee80211_node *ni) { struct ath_softc *sc = arg; const HAL_RATE_TABLE *rt = sc->sc_currates; struct sample_node *sn = ATH_NODE_SAMPLE(ATH_NODE(ni)); uint64_t mask; int rix, y; printf("\n[%s] refcnt %d static_rix (%d %s) ratemask 0x%jx\n", ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni), dot11rate(rt, sn->static_rix), dot11rate_label(rt, sn->static_rix), (uintmax_t)sn->ratemask); for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) { printf("[%4u] cur rix %d (%d %s) since switch: packets %d ticks %u\n", bin_to_size(y), sn->current_rix[y], dot11rate(rt, sn->current_rix[y]), dot11rate_label(rt, sn->current_rix[y]), sn->packets_since_switch[y], sn->ticks_since_switch[y]); printf("[%4u] last sample (%d %s) cur sample (%d %s) packets sent %d\n", bin_to_size(y), dot11rate(rt, sn->last_sample_rix[y]), dot11rate_label(rt, sn->last_sample_rix[y]), dot11rate(rt, sn->current_sample_rix[y]), dot11rate_label(rt, sn->current_sample_rix[y]), sn->packets_sent[y]); printf("[%4u] packets since sample %d sample tt %u\n", bin_to_size(y), sn->packets_since_sample[y], sn->sample_tt[y]); } for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) { if ((mask & 1) == 0) continue; for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) { if (sn->stats[y][rix].total_packets == 0) continue; printf("[%2u %s:%4u] %8ju:%-8ju (%3d%%) (EWMA %3d.%1d%%) T %8ju F %4d avg %5u last %u\n", dot11rate(rt, rix), dot11rate_label(rt, rix), bin_to_size(y), (uintmax_t) sn->stats[y][rix].total_packets, (uintmax_t) sn->stats[y][rix].packets_acked, (int) ((sn->stats[y][rix].packets_acked * 100ULL) / sn->stats[y][rix].total_packets), sn->stats[y][rix].ewma_pct / 10, sn->stats[y][rix].ewma_pct % 10, (uintmax_t) sn->stats[y][rix].tries, sn->stats[y][rix].successive_failures, sn->stats[y][rix].average_tx_time, ticks - sn->stats[y][rix].last_tx); } } } static int ath_rate_sysctl_stats(SYSCTL_HANDLER_ARGS) { struct ath_softc *sc = arg1; struct ieee80211com *ic = &sc->sc_ic; int error, v; v = 0; error = sysctl_handle_int(oidp, &v, 0, req); if (error || !req->newptr) return error; ieee80211_iterate_nodes(&ic->ic_sta, sample_stats, sc); return 0; } static int ath_rate_sysctl_smoothing_rate(SYSCTL_HANDLER_ARGS) { struct sample_softc *ssc = arg1; int rate, error; rate = ssc->smoothing_rate; error = sysctl_handle_int(oidp, &rate, 0, req); if (error || !req->newptr) return error; if (!(0 <= rate && rate < 100)) return EINVAL; ssc->smoothing_rate = rate; ssc->smoothing_minpackets = 100 / (100 - rate); return 0; } static int ath_rate_sysctl_sample_rate(SYSCTL_HANDLER_ARGS) { struct sample_softc *ssc = arg1; int rate, error; rate = ssc->sample_rate; error = sysctl_handle_int(oidp, &rate, 0, req); if (error || !req->newptr) return error; if (!(2 <= rate && rate <= 100)) return EINVAL; ssc->sample_rate = rate; return 0; } static void ath_rate_sysctlattach(struct ath_softc *sc, struct sample_softc *ssc) { struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev); struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev); SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, "smoothing_rate", CTLTYPE_INT | CTLFLAG_RW, ssc, 0, ath_rate_sysctl_smoothing_rate, "I", "sample: smoothing rate for avg tx time (%%)"); SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, "sample_rate", CTLTYPE_INT | CTLFLAG_RW, ssc, 0, ath_rate_sysctl_sample_rate, "I", "sample: percent air time devoted to sampling new rates (%%)"); /* XXX max_successive_failures, stale_failure_timeout, min_switch */ SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, "sample_stats", CTLTYPE_INT | CTLFLAG_RW, sc, 0, ath_rate_sysctl_stats, "I", "sample: print statistics"); } struct ath_ratectrl * ath_rate_attach(struct ath_softc *sc) { struct sample_softc *ssc; ssc = malloc(sizeof(struct sample_softc), M_DEVBUF, M_NOWAIT|M_ZERO); if (ssc == NULL) return NULL; ssc->arc.arc_space = sizeof(struct sample_node); ssc->smoothing_rate = 75; /* ewma percentage ([0..99]) */ ssc->smoothing_minpackets = 100 / (100 - ssc->smoothing_rate); ssc->sample_rate = 10; /* %time to try diff tx rates */ ssc->max_successive_failures = 3; /* threshold for rate sampling*/ ssc->stale_failure_timeout = 10 * hz; /* 10 seconds */ ssc->min_switch = hz; /* 1 second */ ath_rate_sysctlattach(sc, ssc); return &ssc->arc; } void ath_rate_detach(struct ath_ratectrl *arc) { struct sample_softc *ssc = (struct sample_softc *) arc; free(ssc, M_DEVBUF); }