/*- * 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_inet.h" #include "opt_wlan.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef INET #include #include #endif #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. */ #define STALE_FAILURE_TIMEOUT_MS 10000 #define MIN_SWITCH_MS 1000 static void ath_rate_ctl_reset(struct ath_softc *, struct ieee80211_node *); static __inline int size_to_bin(int size) { int x = 0; for (x = 0; x < NUM_PACKET_SIZE_BINS; x++) { if (size <= packet_size_bins[x]) { return x; } } return NUM_PACKET_SIZE_BINS-1; } static __inline int bin_to_size(int index) { return packet_size_bins[index]; } static __inline int rate_to_ndx(struct sample_node *sn, int rate) { int x = 0; for (x = 0; x < sn->num_rates; x++) { if (sn->rates[x].rate == rate) { return x; } } return -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) { } /* * returns the ndx with the lowest average_tx_time, * or -1 if all the average_tx_times are 0. */ static __inline int best_rate_ndx(struct sample_node *sn, int size_bin, int require_acked_before) { int x = 0; int best_rate_ndx = 0; int best_rate_tt = 0; for (x = 0; x < sn->num_rates; x++) { int tt = sn->stats[size_bin][x].average_tx_time; if (tt <= 0 || (require_acked_before && !sn->stats[size_bin][x].packets_acked)) { continue; } /* 9 megabits never works better than 12 */ if (sn->rates[x].rate == 18) continue; /* don't use a bit-rate that has been failing */ if (sn->stats[size_bin][x].successive_failures > 3) continue; if (!best_rate_tt || best_rate_tt > tt) { best_rate_tt = tt; best_rate_ndx = x; } } return (best_rate_tt) ? best_rate_ndx : -1; } /* * pick a good "random" bit-rate to sample other than the current one */ static __inline int pick_sample_ndx(struct sample_node *sn, int size_bin) { int x = 0; int current_ndx = 0; unsigned current_tt = 0; current_ndx = sn->current_rate[size_bin]; if (current_ndx < 0) { /* no successes yet, send at the lowest bit-rate */ return 0; } current_tt = sn->stats[size_bin][current_ndx].average_tx_time; for (x = 0; x < sn->num_rates; x++) { int ndx = (sn->last_sample_ndx[size_bin]+1+x) % sn->num_rates; /* don't sample the current bit-rate */ if (ndx == current_ndx) continue; /* this bit-rate is always worse than the current one */ if (sn->stats[size_bin][ndx].perfect_tx_time > current_tt) continue; /* rarely sample bit-rates that fail a lot */ if (ticks - sn->stats[size_bin][ndx].last_tx < ((hz * STALE_FAILURE_TIMEOUT_MS)/1000) && sn->stats[size_bin][ndx].successive_failures > 3) continue; /* don't sample more than 2 indexes higher * for rates higher than 11 megabits */ if (sn->rates[ndx].rate > 22 && ndx > current_ndx + 2) continue; /* 9 megabits never works better than 12 */ if (sn->rates[ndx].rate == 18) continue; /* if we're using 11 megabits, only sample up to 12 megabits */ if (sn->rates[current_ndx].rate == 22 && ndx > current_ndx + 1) continue; sn->last_sample_ndx[size_bin] = ndx; return ndx; } return current_ndx; } 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 sample_node *sn = ATH_NODE_SAMPLE(an); struct sample_softc *ssc = ATH_SOFTC_SAMPLE(sc); struct ifnet *ifp = sc->sc_ifp; struct ieee80211com *ic = ifp->if_l2com; int ndx, size_bin, mrr, best_ndx, change_rates; unsigned average_tx_time; mrr = sc->sc_mrretry && !(ic->ic_flags & IEEE80211_F_USEPROT); size_bin = size_to_bin(frameLen); best_ndx = best_rate_ndx(sn, size_bin, !mrr); if (best_ndx >= 0) { average_tx_time = sn->stats[size_bin][best_ndx].average_tx_time; } else { average_tx_time = 0; } if (sn->static_rate_ndx != -1) { ndx = sn->static_rate_ndx; *try0 = ATH_TXMAXTRY; } else { *try0 = mrr ? 2 : ATH_TXMAXTRY; if (sn->sample_tt[size_bin] < average_tx_time * (sn->packets_since_sample[size_bin]*ssc->ath_sample_rate/100)) { /* * we want to limit the time measuring the performance * of other bit-rates to ath_sample_rate% of the * total transmission time. */ ndx = pick_sample_ndx(sn, size_bin); if (ndx != sn->current_rate[size_bin]) { sn->current_sample_ndx[size_bin] = ndx; } else { sn->current_sample_ndx[size_bin] = -1; } sn->packets_since_sample[size_bin] = 0; } else { change_rates = 0; if (!sn->packets_sent[size_bin] || best_ndx == -1) { /* no packet has been sent successfully yet */ for (ndx = sn->num_rates-1; ndx > 0; ndx--) { /* * pick the highest rate <= 36 Mbps * that hasn't failed. */ if (sn->rates[ndx].rate <= 72 && sn->stats[size_bin][ndx].successive_failures == 0) { break; } } change_rates = 1; best_ndx = ndx; } else if (sn->packets_sent[size_bin] < 20) { /* let the bit-rate switch quickly during the first few packets */ change_rates = 1; } else if (ticks - ((hz*MIN_SWITCH_MS)/1000) > sn->ticks_since_switch[size_bin]) { /* 2 seconds have gone by */ change_rates = 1; } else if (average_tx_time * 2 < sn->stats[size_bin][sn->current_rate[size_bin]].average_tx_time) { /* the current bit-rate is twice as slow as the best one */ change_rates = 1; } sn->packets_since_sample[size_bin]++; if (change_rates) { if (best_ndx != sn->current_rate[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__, packet_size_bins[size_bin], sn->rates[sn->current_rate[size_bin]].rate, sn->stats[size_bin][sn->current_rate[size_bin]].average_tx_time, sn->stats[size_bin][sn->current_rate[size_bin]].perfect_tx_time, sn->rates[best_ndx].rate, sn->stats[size_bin][best_ndx].average_tx_time, sn->stats[size_bin][best_ndx].perfect_tx_time, sn->packets_since_switch[size_bin], mrr); } sn->packets_since_switch[size_bin] = 0; sn->current_rate[size_bin] = best_ndx; sn->ticks_since_switch[size_bin] = ticks; /* * Set the visible txrate for this node. */ an->an_node.ni_txrate = sn->rates[best_ndx].rate; } ndx = sn->current_rate[size_bin]; sn->packets_since_switch[size_bin]++; } } KASSERT(ndx >= 0 && ndx < sn->num_rates, ("ndx is %d", ndx)); *rix = sn->rates[ndx].rix; if (shortPreamble) { *txrate = sn->rates[ndx].shortPreambleRateCode; } else { *txrate = sn->rates[ndx].rateCode; } sn->packets_sent[size_bin]++; } 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); int rateCode = -1; int frame_size = 0; int size_bin = 0; int ndx = 0; size_bin = size_to_bin(frame_size); // TODO: it's correct that frame_size alway 0 ? ndx = sn->current_rate[size_bin]; /* retry at the current bit-rate */ if (!sn->stats[size_bin][ndx].packets_acked) { ndx = 0; /* use the lowest bit-rate */ } if (shortPreamble) { rateCode = sn->rates[ndx].shortPreambleRateCode; } else { rateCode = sn->rates[ndx].rateCode; } ath_hal_setupxtxdesc(sc->sc_ah, ds , rateCode, 3 /* series 1 */ , sn->rates[0].rateCode, 3 /* series 2 */ , 0, 0 /* series 3 */ ); } static void update_stats(struct ath_softc *sc, struct ath_node *an, int frame_size, int ndx0, int tries0, int ndx1, int tries1, int ndx2, int tries2, int ndx3, int tries3, int short_tries, int tries, int status) { struct sample_node *sn = ATH_NODE_SAMPLE(an); struct sample_softc *ssc = ATH_SOFTC_SAMPLE(sc); int tt = 0; int tries_so_far = 0; int size_bin = 0; int size = 0; int rate = 0; size_bin = size_to_bin(frame_size); size = bin_to_size(size_bin); if (!(0 <= ndx0 && ndx0 < sn->num_rates)) { printf("%s: bogus ndx0 %d, max %u, mode %u\n", __func__, ndx0, sn->num_rates, sc->sc_curmode); return; } rate = sn->rates[ndx0].rate; tt += calc_usecs_unicast_packet(sc, size, sn->rates[ndx0].rix, short_tries, MIN(tries0, tries) - 1); tries_so_far += tries0; if (tries1 && tries0 < tries) { if (!(0 <= ndx1 && ndx1 < sn->num_rates)) { printf("%s: bogus ndx1 %d, max %u, mode %u\n", __func__, ndx1, sn->num_rates, sc->sc_curmode); return; } tt += calc_usecs_unicast_packet(sc, size, sn->rates[ndx1].rix, short_tries, MIN(tries1 + tries_so_far, tries) - tries_so_far - 1); } tries_so_far += tries1; if (tries2 && tries0 + tries1 < tries) { if (!(0 <= ndx2 && ndx2 < sn->num_rates)) { printf("%s: bogus ndx2 %d, max %u, mode %u\n", __func__, ndx2, sn->num_rates, sc->sc_curmode); return; } tt += calc_usecs_unicast_packet(sc, size, sn->rates[ndx2].rix, short_tries, MIN(tries2 + tries_so_far, tries) - tries_so_far - 1); } tries_so_far += tries2; if (tries3 && tries0 + tries1 + tries2 < tries) { if (!(0 <= ndx3 && ndx3 < sn->num_rates)) { printf("%s: bogus ndx3 %d, max %u, mode %u\n", __func__, ndx3, sn->num_rates, sc->sc_curmode); return; } tt += calc_usecs_unicast_packet(sc, size, sn->rates[ndx3].rix, short_tries, MIN(tries3 + tries_so_far, tries) - tries_so_far - 1); } if (sn->stats[size_bin][ndx0].total_packets < (100 / (100 - ssc->ath_smoothing_rate))) { /* just average the first few packets */ int avg_tx = sn->stats[size_bin][ndx0].average_tx_time; int packets = sn->stats[size_bin][ndx0].total_packets; sn->stats[size_bin][ndx0].average_tx_time = (tt+(avg_tx*packets))/(packets+1); } else { /* use a ewma */ sn->stats[size_bin][ndx0].average_tx_time = ((sn->stats[size_bin][ndx0].average_tx_time * ssc->ath_smoothing_rate) + (tt * (100 - ssc->ath_smoothing_rate))) / 100; } if (status) { int y; sn->stats[size_bin][ndx0].successive_failures++; 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 lower * bit-rate then a larger one will also. */ sn->stats[y][ndx0].successive_failures++; sn->stats[y][ndx0].last_tx = ticks; sn->stats[y][ndx0].tries += tries; sn->stats[y][ndx0].total_packets++; } } else { sn->stats[size_bin][ndx0].packets_acked++; sn->stats[size_bin][ndx0].successive_failures = 0; } sn->stats[size_bin][ndx0].tries += tries; sn->stats[size_bin][ndx0].last_tx = ticks; sn->stats[size_bin][ndx0].total_packets++; if (ndx0 == sn->current_sample_ndx[size_bin]) { IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, &an->an_node, "%s: size %d %s sample rate %d tries (%d/%d) tt %d avg_tt (%d/%d)", __func__, size, status ? "FAIL" : "OK", rate, short_tries, tries, tt, sn->stats[size_bin][ndx0].average_tx_time, sn->stats[size_bin][ndx0].perfect_tx_time); sn->sample_tt[size_bin] = tt; sn->current_sample_ndx[size_bin] = -1; } } void ath_rate_tx_complete(struct ath_softc *sc, struct ath_node *an, const struct ath_buf *bf) { struct ifnet *ifp = sc->sc_ifp; struct ieee80211com *ic = ifp->if_l2com; struct sample_node *sn = ATH_NODE_SAMPLE(an); const struct ath_tx_status *ts = &bf->bf_status.ds_txstat; const struct ath_desc *ds0 = &bf->bf_desc[0]; int final_rate, short_tries, long_tries, frame_size; int mrr; final_rate = sc->sc_hwmap[ts->ts_rate &~ HAL_TXSTAT_ALTRATE].ieeerate; short_tries = ts->ts_shortretry; long_tries = ts->ts_longretry + 1; frame_size = ds0->ds_ctl0 & 0x0fff; /* low-order 12 bits of ds_ctl0 */ if (frame_size == 0) /* NB: should not happen */ frame_size = 1500; if (sn->num_rates <= 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)), ts->ts_status ? "FAIL" : "OK", short_tries, long_tries); return; } mrr = sc->sc_mrretry && !(ic->ic_flags & IEEE80211_F_USEPROT); if (!mrr || !(ts->ts_rate & HAL_TXSTAT_ALTRATE)) { int ndx = rate_to_ndx(sn, final_rate); /* * Only one rate was used; optimize work. */ IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, &an->an_node, "%s: size %d %s rate/try %d/%d/%d", __func__, bin_to_size(size_to_bin(frame_size)), ts->ts_status ? "FAIL" : "OK", final_rate, short_tries, long_tries); update_stats(sc, an, frame_size, ndx, long_tries, 0, 0, 0, 0, 0, 0, short_tries, long_tries, ts->ts_status); } else { int hwrate0, rate0, tries0, ndx0; int hwrate1, rate1, tries1, ndx1; int hwrate2, rate2, tries2, ndx2; int hwrate3, rate3, tries3, ndx3; int finalTSIdx = ts->ts_finaltsi; /* * Process intermediate rates that failed. */ if (sc->sc_ah->ah_magic != 0x20065416) { hwrate0 = MS(ds0->ds_ctl3, AR_XmitRate0); hwrate1 = MS(ds0->ds_ctl3, AR_XmitRate1); hwrate2 = MS(ds0->ds_ctl3, AR_XmitRate2); hwrate3 = MS(ds0->ds_ctl3, AR_XmitRate3); } else { hwrate0 = MS(ds0->ds_ctl3, AR5416_XmitRate0); hwrate1 = MS(ds0->ds_ctl3, AR5416_XmitRate1); hwrate2 = MS(ds0->ds_ctl3, AR5416_XmitRate2); hwrate3 = MS(ds0->ds_ctl3, AR5416_XmitRate3); } rate0 = sc->sc_hwmap[hwrate0].ieeerate; tries0 = MS(ds0->ds_ctl2, AR_XmitDataTries0); ndx0 = rate_to_ndx(sn, rate0); rate1 = sc->sc_hwmap[hwrate1].ieeerate; tries1 = MS(ds0->ds_ctl2, AR_XmitDataTries1); ndx1 = rate_to_ndx(sn, rate1); rate2 = sc->sc_hwmap[hwrate2].ieeerate; tries2 = MS(ds0->ds_ctl2, AR_XmitDataTries2); ndx2 = rate_to_ndx(sn, rate2); rate3 = sc->sc_hwmap[hwrate3].ieeerate; tries3 = MS(ds0->ds_ctl2, AR_XmitDataTries3); ndx3 = rate_to_ndx(sn, rate3); IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, &an->an_node, "%s: size %d finaltsidx %d tries %d %s rate/try [%d/%d %d/%d %d/%d %d/%d]", __func__, bin_to_size(size_to_bin(frame_size)), finalTSIdx, long_tries, ts->ts_status ? "FAIL" : "OK", rate0, tries0, rate1, tries1, rate2, tries2, rate3, tries3); /* * 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 (tries0) { update_stats(sc, an, frame_size, ndx0, tries0, ndx1, tries1, ndx2, tries2, ndx3, tries3, short_tries, long_tries, long_tries > tries0); long_tries -= tries0; } if (tries1 && finalTSIdx > 0) { update_stats(sc, an, frame_size, ndx1, tries1, ndx2, tries2, ndx3, tries3, 0, 0, short_tries, long_tries, ts->ts_status); long_tries -= tries1; } if (tries2 && finalTSIdx > 1) { update_stats(sc, an, frame_size, ndx2, tries2, ndx3, tries3, 0, 0, 0, 0, short_tries, long_tries, ts->ts_status); long_tries -= tries2; } if (tries3 && finalTSIdx > 2) { update_stats(sc, an, frame_size, ndx3, tries3, 0, 0, 0, 0, 0, 0, short_tries, long_tries, ts->ts_status); } } } void ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew) { if (isnew) ath_rate_ctl_reset(sc, &an->an_node); } /* * 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) struct ath_node *an = ATH_NODE(ni); const struct ieee80211_txparam *tp = an->an_tp; struct sample_node *sn = ATH_NODE_SAMPLE(an); const HAL_RATE_TABLE *rt = sc->sc_currates; int x, y, srate; KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode)); sn->static_rate_ndx = -1; if (tp != NULL && tp->ucastrate != IEEE80211_FIXED_RATE_NONE) { /* * A fixed rate is to be used; ic_fixed_rate is the * IEEE code for this rate (sans basic bit). Convert this * to the index into the negotiated rate set for * the node. */ /* NB: the rate set is assumed sorted */ srate = ni->ni_rates.rs_nrates - 1; for (; srate >= 0 && RATE(srate) != tp->ucastrate; srate--) ; /* * The fixed rate may not be available due to races * and mode settings. Also orphaned nodes created in * adhoc mode may not have any rate set so this lookup * can fail. */ if (srate >= 0) sn->static_rate_ndx = srate; } sn->num_rates = ni->ni_rates.rs_nrates; for (x = 0; x < ni->ni_rates.rs_nrates; x++) { sn->rates[x].rate = ni->ni_rates.rs_rates[x] & IEEE80211_RATE_VAL; sn->rates[x].rix = sc->sc_rixmap[sn->rates[x].rate]; if (sn->rates[x].rix == 0xff) { IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, "%s: ignore bogus rix at %d", __func__, x); continue; } sn->rates[x].rateCode = rt->info[sn->rates[x].rix].rateCode; sn->rates[x].shortPreambleRateCode = rt->info[sn->rates[x].rix].rateCode | rt->info[sn->rates[x].rix].shortPreamble; } #ifdef IEEE80211_DEBUG if (ieee80211_msg(ni->ni_vap, IEEE80211_MSG_RATECTL)) { ieee80211_note(ni->ni_vap, "[%6D] %s: size 1600 rate/tt", __func__, ni->ni_macaddr, ":"); for (x = 0; x < sn->num_rates; x++) { if (sn->rates[x].rix == 0xff) continue; printf(" %d/%d", sn->rates[x].rate, calc_usecs_unicast_packet(sc, 1600, sn->rates[x].rix, 0,0)); } printf("\n"); } #endif for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) { int size = bin_to_size(y); int ndx = 0; sn->packets_sent[y] = 0; sn->current_sample_ndx[y] = -1; sn->last_sample_ndx[y] = 0; for (x = 0; x < ni->ni_rates.rs_nrates; x++) { sn->stats[y][x].successive_failures = 0; sn->stats[y][x].tries = 0; sn->stats[y][x].total_packets = 0; sn->stats[y][x].packets_acked = 0; sn->stats[y][x].last_tx = 0; sn->stats[y][x].perfect_tx_time = calc_usecs_unicast_packet(sc, size, sn->rates[x].rix, 0, 0); sn->stats[y][x].average_tx_time = sn->stats[y][x].perfect_tx_time; } /* set the initial rate */ for (ndx = sn->num_rates-1; ndx > 0; ndx--) { if (sn->rates[ndx].rate <= 72) { break; } } sn->current_rate[y] = ndx; } IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, "%s: %d rates %d%sMbps (%dus)- %d%sMbps (%dus)", __func__, sn->num_rates, sn->rates[0].rate/2, sn->rates[0].rate % 0x1 ? ".5" : "", sn->stats[1][0].perfect_tx_time, sn->rates[sn->num_rates-1].rate/2, sn->rates[sn->num_rates-1].rate % 0x1 ? ".5" : "", sn->stats[1][sn->num_rates-1].perfect_tx_time ); /* set the visible bit-rate */ if (sn->static_rate_ndx != -1) ni->ni_txrate = sn->rates[sn->static_rate_ndx].rate; else ni->ni_txrate = sn->rates[0].rate; #undef RATE } static void rate_cb(void *arg, struct ieee80211_node *ni) { struct ath_softc *sc = arg; ath_rate_newassoc(sc, ATH_NODE(ni), 1); } /* * Reset the rate control state for each 802.11 state transition. */ void ath_rate_newstate(struct ieee80211vap *vap, enum ieee80211_state state) { struct ieee80211com *ic = vap->iv_ic; struct ath_softc *sc = ic->ic_ifp->if_softc; if (state == IEEE80211_S_RUN) { if (vap->iv_opmode != IEEE80211_M_STA) { /* * Sync rates for associated stations and neighbors. */ ieee80211_iterate_nodes(&ic->ic_sta, rate_cb, sc); } ath_rate_newassoc(sc, ATH_NODE(vap->iv_bss), 1); } } static void ath_rate_sysctlattach(struct ath_softc *sc, struct sample_softc *osc) { struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev); struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev); /* XXX bounds check [0..100] */ SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, "smoothing_rate", CTLFLAG_RW, &osc->ath_smoothing_rate, 0, "rate control: retry threshold to credit rate raise (%%)"); /* XXX bounds check [2..100] */ SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, "sample_rate", CTLFLAG_RW, &osc->ath_sample_rate,0, "rate control: # good periods before raising rate"); } struct ath_ratectrl * ath_rate_attach(struct ath_softc *sc) { struct sample_softc *osc; osc = malloc(sizeof(struct sample_softc), M_DEVBUF, M_NOWAIT|M_ZERO); if (osc == NULL) return NULL; osc->arc.arc_space = sizeof(struct sample_node); osc->ath_smoothing_rate = 95; /* ewma percentage (out of 100) */ osc->ath_sample_rate = 10; /* send a different bit-rate 1/X packets */ ath_rate_sysctlattach(sc, osc); return &osc->arc; } void ath_rate_detach(struct ath_ratectrl *arc) { struct sample_softc *osc = (struct sample_softc *) arc; free(osc, M_DEVBUF); } /* * Module glue. */ static int sample_modevent(module_t mod, int type, void *unused) { switch (type) { case MOD_LOAD: if (bootverbose) printf("ath_rate: version 1.2 \n"); return 0; case MOD_UNLOAD: return 0; } return EINVAL; } static moduledata_t sample_mod = { "ath_rate", sample_modevent, 0 }; DECLARE_MODULE(ath_rate, sample_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST); MODULE_VERSION(ath_rate, 1); MODULE_DEPEND(ath_rate, ath_hal, 1, 1, 1); /* Atheros HAL */ MODULE_DEPEND(ath_rate, wlan, 1, 1, 1);