2 * Copyright (c) 2005 John Bicket
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer,
10 * without modification.
11 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
12 * similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
13 * redistribution must be conditioned upon including a substantially
14 * similar Disclaimer requirement for further binary redistribution.
15 * 3. Neither the names of the above-listed copyright holders nor the names
16 * of any contributors may be used to endorse or promote products derived
17 * from this software without specific prior written permission.
19 * Alternatively, this software may be distributed under the terms of the
20 * GNU General Public License ("GPL") version 2 as published by the Free
21 * Software Foundation.
24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
25 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
26 * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
27 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
28 * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
29 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
32 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
34 * THE POSSIBILITY OF SUCH DAMAGES.
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
42 * John Bicket's SampleRate control algorithm.
47 #include <sys/param.h>
48 #include <sys/systm.h>
49 #include <sys/sysctl.h>
50 #include <sys/kernel.h>
52 #include <sys/mutex.h>
53 #include <sys/errno.h>
55 #include <machine/bus.h>
56 #include <machine/resource.h>
59 #include <sys/socket.h>
62 #include <net/if_media.h>
63 #include <net/if_arp.h>
64 #include <net/ethernet.h> /* XXX for ether_sprintf */
66 #include <net80211/ieee80211_var.h>
71 #include <netinet/in.h>
72 #include <netinet/if_ether.h>
75 #include <dev/ath/if_athvar.h>
76 #include <dev/ath/ath_rate/sample/sample.h>
77 #include <dev/ath/ath_hal/ah_desc.h>
80 * This file is an implementation of the SampleRate algorithm
81 * in "Bit-rate Selection in Wireless Networks"
82 * (http://www.pdos.lcs.mit.edu/papers/jbicket-ms.ps)
84 * SampleRate chooses the bit-rate it predicts will provide the most
85 * throughput based on estimates of the expected per-packet
86 * transmission time for each bit-rate. SampleRate periodically sends
87 * packets at bit-rates other than the current one to estimate when
88 * another bit-rate will provide better performance. SampleRate
89 * switches to another bit-rate when its estimated per-packet
90 * transmission time becomes smaller than the current bit-rate's.
91 * SampleRate reduces the number of bit-rates it must sample by
92 * eliminating those that could not perform better than the one
93 * currently being used. SampleRate also stops probing at a bit-rate
94 * if it experiences several successive losses.
96 * The difference between the algorithm in the thesis and the one in this
97 * file is that the one in this file uses a ewma instead of a window.
99 * Also, this implementation tracks the average transmission time for
100 * a few different packet sizes independently for each link.
103 static void ath_rate_ctl_reset(struct ath_softc *, struct ieee80211_node *);
105 static const int packet_size_bins[NUM_PACKET_SIZE_BINS] = { 250, 1600 };
108 size_to_bin(int size)
110 #if NUM_PACKET_SIZE_BINS > 1
111 if (size <= packet_size_bins[0])
114 #if NUM_PACKET_SIZE_BINS > 2
115 if (size <= packet_size_bins[1])
118 #if NUM_PACKET_SIZE_BINS > 3
119 if (size <= packet_size_bins[2])
122 #if NUM_PACKET_SIZE_BINS > 4
123 #error "add support for more packet sizes"
125 return NUM_PACKET_SIZE_BINS-1;
129 bin_to_size(int index)
131 return packet_size_bins[index];
135 ath_rate_node_init(struct ath_softc *sc, struct ath_node *an)
137 /* NB: assumed to be zero'd by caller */
141 ath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an)
146 * Return the rix with the lowest average_tx_time,
147 * or -1 if all the average_tx_times are 0.
150 pick_best_rate(struct sample_node *sn, const HAL_RATE_TABLE *rt,
151 int size_bin, int require_acked_before)
153 int best_rate_rix, best_rate_tt;
159 for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) {
160 if ((mask & 1) == 0) /* not a supported rate */
163 tt = sn->stats[size_bin][rix].average_tx_time;
165 (require_acked_before &&
166 !sn->stats[size_bin][rix].packets_acked))
169 /* don't use a bit-rate that has been failing */
170 if (sn->stats[size_bin][rix].successive_failures > 3)
173 if (best_rate_tt == 0 || tt < best_rate_tt) {
178 return (best_rate_tt ? best_rate_rix : -1);
182 * Pick a good "random" bit-rate to sample other than the current one.
185 pick_sample_rate(struct sample_softc *ssc , struct sample_node *sn,
186 const HAL_RATE_TABLE *rt, int size_bin)
188 #define DOT11RATE(ix) (rt->info[ix].dot11Rate & IEEE80211_RATE_VAL)
189 int current_rix, rix;
193 current_rix = sn->current_rix[size_bin];
194 if (current_rix < 0) {
195 /* no successes yet, send at the lowest bit-rate */
199 current_tt = sn->stats[size_bin][current_rix].average_tx_time;
201 rix = sn->last_sample_rix[size_bin]+1; /* next sample rate */
202 mask = sn->ratemask &~ (1<<current_rix);/* don't sample current rate */
204 if ((mask & (1<<rix)) == 0) { /* not a supported rate */
206 if (++rix >= rt->rateCount)
211 /* this bit-rate is always worse than the current one */
212 if (sn->stats[size_bin][rix].perfect_tx_time > current_tt) {
217 /* rarely sample bit-rates that fail a lot */
218 if (sn->stats[size_bin][rix].successive_failures > ssc->max_successive_failures &&
219 ticks - sn->stats[size_bin][rix].last_tx < ssc->stale_failure_timeout) {
224 /* don't sample more than 2 rates higher for rates > 11M */
225 if (DOT11RATE(rix) > 2*11 && rix > current_rix + 2) {
230 sn->last_sample_rix[size_bin] = rix;
238 ath_rate_findrate(struct ath_softc *sc, struct ath_node *an,
239 int shortPreamble, size_t frameLen,
240 u_int8_t *rix0, int *try0, u_int8_t *txrate)
242 #define DOT11RATE(ix) (rt->info[ix].dot11Rate & IEEE80211_RATE_VAL)
243 #define RATE(ix) (DOT11RATE(ix) / 2)
244 struct sample_node *sn = ATH_NODE_SAMPLE(an);
245 struct sample_softc *ssc = ATH_SOFTC_SAMPLE(sc);
246 struct ifnet *ifp = sc->sc_ifp;
247 struct ieee80211com *ic = ifp->if_l2com;
248 const HAL_RATE_TABLE *rt = sc->sc_currates;
249 const int size_bin = size_to_bin(frameLen);
250 int rix, mrr, best_rix, change_rates;
251 unsigned average_tx_time;
253 if (sn->static_rix != -1) {
254 rix = sn->static_rix;
255 *try0 = ATH_TXMAXTRY;
259 mrr = sc->sc_mrretry && !(ic->ic_flags & IEEE80211_F_USEPROT);
261 best_rix = pick_best_rate(sn, rt, size_bin, !mrr);
263 average_tx_time = sn->stats[size_bin][best_rix].average_tx_time;
268 * Limit the time measuring the performance of other tx
269 * rates to sample_rate% of the total transmission time.
271 if (sn->sample_tt[size_bin] < average_tx_time * (sn->packets_since_sample[size_bin]*ssc->sample_rate/100)) {
272 rix = pick_sample_rate(ssc, sn, rt, size_bin);
273 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL,
274 &an->an_node, "size %u sample rate %d current rate %d",
275 bin_to_size(size_bin), RATE(rix),
276 RATE(sn->current_rix[size_bin]));
277 if (rix != sn->current_rix[size_bin]) {
278 sn->current_sample_rix[size_bin] = rix;
280 sn->current_sample_rix[size_bin] = -1;
282 sn->packets_since_sample[size_bin] = 0;
285 if (!sn->packets_sent[size_bin] || best_rix == -1) {
286 /* no packet has been sent successfully yet */
287 for (rix = rt->rateCount-1; rix > 0; rix--) {
288 if ((sn->ratemask & (1<<rix)) == 0)
291 * Pick the highest rate <= 36 Mbps
292 * that hasn't failed.
294 if (DOT11RATE(rix) <= 72 &&
295 sn->stats[size_bin][rix].successive_failures == 0) {
301 } else if (sn->packets_sent[size_bin] < 20) {
302 /* let the bit-rate switch quickly during the first few packets */
304 } else if (ticks - ssc->min_switch > sn->ticks_since_switch[size_bin]) {
305 /* min_switch seconds have gone by */
307 } else if (2*average_tx_time < sn->stats[size_bin][sn->current_rix[size_bin]].average_tx_time) {
308 /* the current bit-rate is twice as slow as the best one */
312 sn->packets_since_sample[size_bin]++;
315 if (best_rix != sn->current_rix[size_bin]) {
316 IEEE80211_NOTE(an->an_node.ni_vap,
317 IEEE80211_MSG_RATECTL,
319 "%s: size %d switch rate %d (%d/%d) -> %d (%d/%d) after %d packets mrr %d",
321 bin_to_size(size_bin),
322 RATE(sn->current_rix[size_bin]),
323 sn->stats[size_bin][sn->current_rix[size_bin]].average_tx_time,
324 sn->stats[size_bin][sn->current_rix[size_bin]].perfect_tx_time,
326 sn->stats[size_bin][best_rix].average_tx_time,
327 sn->stats[size_bin][best_rix].perfect_tx_time,
328 sn->packets_since_switch[size_bin],
331 sn->packets_since_switch[size_bin] = 0;
332 sn->current_rix[size_bin] = best_rix;
333 sn->ticks_since_switch[size_bin] = ticks;
335 * Set the visible txrate for this node.
337 an->an_node.ni_txrate = DOT11RATE(best_rix);
339 rix = sn->current_rix[size_bin];
340 sn->packets_since_switch[size_bin]++;
342 *try0 = mrr ? sn->sched[rix].t0 : ATH_TXMAXTRY;
344 KASSERT(rix >= 0 && rix < rt->rateCount, ("rix is %d", rix));
347 *txrate = rt->info[rix].rateCode
348 | (shortPreamble ? rt->info[rix].shortPreamble : 0);
349 sn->packets_sent[size_bin]++;
355 (((_r) == 6) ? 0 : (((_r) == 9) ? 1 : (((_r) == 12) ? 2 : \
356 (((_r) == 18) ? 3 : (((_r) == 24) ? 4 : (((_r) == 36) ? 5 : \
357 (((_r) == 48) ? 6 : (((_r) == 54) ? 7 : 0))))))))
358 static const struct txschedule series_11a[] = {
359 { 3,A( 6), 3,A( 6), 0,A( 6), 0,A( 6) }, /* 6Mb/s */
360 { 4,A( 9), 3,A( 6), 4,A( 6), 0,A( 6) }, /* 9Mb/s */
361 { 4,A(12), 3,A( 6), 4,A( 6), 0,A( 6) }, /* 12Mb/s */
362 { 4,A(18), 3,A( 12), 4,A( 6), 2,A( 6) }, /* 18Mb/s */
363 { 4,A(24), 3,A( 18), 4,A( 12), 2,A( 6) }, /* 24Mb/s */
364 { 4,A(36), 3,A( 24), 4,A( 18), 2,A( 6) }, /* 36Mb/s */
365 { 4,A(48), 3,A( 36), 4,A( 24), 2,A(12) }, /* 48Mb/s */
366 { 4,A(54), 3,A( 48), 4,A( 36), 2,A(24) } /* 54Mb/s */
371 (((_r) == 1) ? 0 : (((_r) == 2) ? 1 : (((_r) == 5.5) ? 2 : \
372 (((_r) == 11) ? 3 : (((_r) == 6) ? 4 : (((_r) == 9) ? 5 : \
373 (((_r) == 12) ? 6 : (((_r) == 18) ? 7 : (((_r) == 24) ? 8 : \
374 (((_r) == 36) ? 9 : (((_r) == 48) ? 10 : (((_r) == 54) ? 11 : 0))))))))))))
375 static const struct txschedule series_11g[] = {
376 { 3,G( 1), 3,G( 1), 0,G( 1), 0,G( 1) }, /* 1Mb/s */
377 { 4,G( 2), 3,G( 1), 4,G( 1), 0,G( 1) }, /* 2Mb/s */
378 { 4,G(5.5),3,G( 2), 4,G( 1), 2,G( 1) }, /* 5.5Mb/s */
379 { 4,G(11), 3,G(5.5), 4,G( 2), 2,G( 1) }, /* 11Mb/s */
380 { 4,G( 6), 3,G(5.5), 4,G( 2), 2,G( 1) }, /* 6Mb/s */
381 { 4,G( 9), 3,G( 6), 4,G(5.5), 2,G( 1) }, /* 9Mb/s */
382 { 4,G(12), 3,G( 11), 4,G(5.5), 2,G( 1) }, /* 12Mb/s */
383 { 4,G(18), 3,G( 12), 4,G( 11), 2,G( 1) }, /* 18Mb/s */
384 { 4,G(24), 3,G( 18), 4,G( 12), 2,G( 1) }, /* 24Mb/s */
385 { 4,G(36), 3,G( 24), 4,G( 18), 2,G( 1) }, /* 36Mb/s */
386 { 4,G(48), 3,G( 36), 4,G( 24), 2,G( 1) }, /* 48Mb/s */
387 { 4,G(54), 3,G( 48), 4,G( 36), 2,G( 1) } /* 54Mb/s */
392 (((_r) == 3) ? 0 : (((_r) == 4.5) ? 1 : (((_r) == 6) ? 2 : \
393 (((_r) == 9) ? 3 : (((_r) == 12) ? 4 : (((_r) == 18) ? 5 : \
394 (((_r) == 24) ? 6 : (((_r) == 27) ? 7 : 0))))))))
395 static const struct txschedule series_half[] = {
396 { 3,H( 3), 3,H( 3), 0,H( 3), 0,H( 3) }, /* 3Mb/s */
397 { 4,H(4.5),3,H( 3), 4,H( 3), 0,H( 3) }, /* 4.5Mb/s */
398 { 4,H( 6), 3,H( 3), 4,H( 3), 0,H( 3) }, /* 6Mb/s */
399 { 4,H( 9), 3,H( 6), 4,H( 3), 2,H( 3) }, /* 9Mb/s */
400 { 4,H(12), 3,H( 9), 4,H( 6), 2,H( 3) }, /* 12Mb/s */
401 { 4,H(18), 3,H( 12), 4,H( 9), 2,H( 3) }, /* 18Mb/s */
402 { 4,H(24), 3,H( 18), 4,H( 12), 2,H( 6) }, /* 24Mb/s */
403 { 4,H(27), 3,H( 24), 4,H( 18), 2,H(12) } /* 27Mb/s */
408 #undef Q /* sun4v bogosity */
411 (((_r) == 1.5) ? 0 : (((_r) ==2.25) ? 1 : (((_r) == 3) ? 2 : \
412 (((_r) == 4.5) ? 3 : (((_r) == 6) ? 4 : (((_r) == 9) ? 5 : \
413 (((_r) == 12) ? 6 : (((_r) == 13.5)? 7 : 0))))))))
414 static const struct txschedule series_quarter[] = {
415 { 3,Q( 1.5),3,Q(1.5), 0,Q(1.5), 0,Q(1.5) }, /* 1.5Mb/s */
416 { 4,Q(2.25),3,Q(1.5), 4,Q(1.5), 0,Q(1.5) }, /*2.25Mb/s */
417 { 4,Q( 3),3,Q(1.5), 4,Q(1.5), 0,Q(1.5) }, /* 3Mb/s */
418 { 4,Q( 4.5),3,Q( 3), 4,Q(1.5), 2,Q(1.5) }, /* 4.5Mb/s */
419 { 4,Q( 6),3,Q(4.5), 4,Q( 3), 2,Q(1.5) }, /* 6Mb/s */
420 { 4,Q( 9),3,Q( 6), 4,Q(4.5), 2,Q(1.5) }, /* 9Mb/s */
421 { 4,Q( 12),3,Q( 9), 4,Q( 6), 2,Q( 3) }, /* 12Mb/s */
422 { 4,Q(13.5),3,Q( 12), 4,Q( 9), 2,Q( 6) } /*13.5Mb/s */
427 ath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an,
428 struct ath_desc *ds, int shortPreamble, u_int8_t rix)
430 struct sample_node *sn = ATH_NODE_SAMPLE(an);
431 const struct txschedule *sched = &sn->sched[rix];
432 const HAL_RATE_TABLE *rt = sc->sc_currates;
433 uint8_t rix1, s1code, rix2, s2code, rix3, s3code;
435 /* XXX precalculate short preamble tables */
437 s1code = rt->info[rix1].rateCode
438 | (shortPreamble ? rt->info[rix1].shortPreamble : 0);
440 s2code = rt->info[rix2].rateCode
441 | (shortPreamble ? rt->info[rix2].shortPreamble : 0);
443 s3code = rt->info[rix3].rateCode
444 | (shortPreamble ? rt->info[rix3].shortPreamble : 0);
445 ath_hal_setupxtxdesc(sc->sc_ah, ds,
446 s1code, sched->t1, /* series 1 */
447 s2code, sched->t2, /* series 2 */
448 s3code, sched->t3); /* series 3 */
452 update_stats(struct ath_softc *sc, struct ath_node *an,
454 int rix0, int tries0,
455 int rix1, int tries1,
456 int rix2, int tries2,
457 int rix3, int tries3,
458 int short_tries, int tries, int status)
460 struct sample_node *sn = ATH_NODE_SAMPLE(an);
461 struct sample_softc *ssc = ATH_SOFTC_SAMPLE(sc);
462 const int size_bin = size_to_bin(frame_size);
463 const int size = bin_to_size(size_bin);
464 int tt, tries_so_far;
466 if (!IS_RATE_DEFINED(sn, rix0))
468 tt = calc_usecs_unicast_packet(sc, size, rix0, short_tries,
469 MIN(tries0, tries) - 1);
470 tries_so_far = tries0;
472 if (tries1 && tries_so_far < tries) {
473 if (!IS_RATE_DEFINED(sn, rix1))
475 tt += calc_usecs_unicast_packet(sc, size, rix1, short_tries,
476 MIN(tries1 + tries_so_far, tries) - tries_so_far - 1);
477 tries_so_far += tries1;
480 if (tries2 && tries_so_far < tries) {
481 if (!IS_RATE_DEFINED(sn, rix2))
483 tt += calc_usecs_unicast_packet(sc, size, rix2, short_tries,
484 MIN(tries2 + tries_so_far, tries) - tries_so_far - 1);
485 tries_so_far += tries2;
488 if (tries3 && tries_so_far < tries) {
489 if (!IS_RATE_DEFINED(sn, rix3))
491 tt += calc_usecs_unicast_packet(sc, size, rix3, short_tries,
492 MIN(tries3 + tries_so_far, tries) - tries_so_far - 1);
495 if (sn->stats[size_bin][rix0].total_packets < ssc->smoothing_minpackets) {
496 /* just average the first few packets */
497 int avg_tx = sn->stats[size_bin][rix0].average_tx_time;
498 int packets = sn->stats[size_bin][rix0].total_packets;
499 sn->stats[size_bin][rix0].average_tx_time = (tt+(avg_tx*packets))/(packets+1);
502 sn->stats[size_bin][rix0].average_tx_time =
503 ((sn->stats[size_bin][rix0].average_tx_time * ssc->smoothing_rate) +
504 (tt * (100 - ssc->smoothing_rate))) / 100;
509 sn->stats[size_bin][rix0].successive_failures++;
510 for (y = size_bin+1; y < NUM_PACKET_SIZE_BINS; y++) {
512 * Also say larger packets failed since we
513 * assume if a small packet fails at a
514 * bit-rate then a larger one will also.
516 sn->stats[y][rix0].successive_failures++;
517 sn->stats[y][rix0].last_tx = ticks;
518 sn->stats[y][rix0].tries += tries;
519 sn->stats[y][rix0].total_packets++;
522 sn->stats[size_bin][rix0].packets_acked++;
523 sn->stats[size_bin][rix0].successive_failures = 0;
525 sn->stats[size_bin][rix0].tries += tries;
526 sn->stats[size_bin][rix0].last_tx = ticks;
527 sn->stats[size_bin][rix0].total_packets++;
529 if (rix0 == sn->current_sample_rix[size_bin]) {
530 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL,
532 "%s: size %d %s sample rate %d tries (%d/%d) tt %d avg_tt (%d/%d)",
535 status ? "FAIL" : "OK",
536 rix0, short_tries, tries, tt,
537 sn->stats[size_bin][rix0].average_tx_time,
538 sn->stats[size_bin][rix0].perfect_tx_time);
539 sn->sample_tt[size_bin] = tt;
540 sn->current_sample_rix[size_bin] = -1;
545 badrate(struct ifnet *ifp, int series, int hwrate, int tries, int status)
547 if_printf(ifp, "bad series%d hwrate 0x%x, tries %u ts_status 0x%x\n",
548 series, hwrate, tries, status);
552 ath_rate_tx_complete(struct ath_softc *sc, struct ath_node *an,
553 const struct ath_buf *bf)
555 struct ifnet *ifp = sc->sc_ifp;
556 struct ieee80211com *ic = ifp->if_l2com;
557 struct sample_node *sn = ATH_NODE_SAMPLE(an);
558 const struct ath_tx_status *ts = &bf->bf_status.ds_txstat;
559 const struct ath_desc *ds0 = &bf->bf_desc[0];
560 int final_rix, short_tries, long_tries, frame_size;
561 const HAL_RATE_TABLE *rt = sc->sc_currates;
564 final_rix = rt->rateCodeToIndex[ts->ts_rate];
565 short_tries = ts->ts_shortretry;
566 long_tries = ts->ts_longretry + 1;
567 frame_size = ds0->ds_ctl0 & 0x0fff; /* low-order 12 bits of ds_ctl0 */
568 if (frame_size == 0) /* NB: should not happen */
571 if (sn->ratemask == 0) {
572 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL,
574 "%s: size %d %s rate/try %d/%d no rates yet",
576 bin_to_size(size_to_bin(frame_size)),
577 ts->ts_status ? "FAIL" : "OK",
578 short_tries, long_tries);
581 mrr = sc->sc_mrretry && !(ic->ic_flags & IEEE80211_F_USEPROT);
582 if (!mrr || ts->ts_finaltsi == 0) {
583 if (!IS_RATE_DEFINED(sn, final_rix)) {
584 badrate(ifp, 0, ts->ts_rate, long_tries, ts->ts_status);
588 * Only one rate was used; optimize work.
590 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL,
591 &an->an_node, "%s: size %d %s rate/try %d/%d/%d",
593 bin_to_size(size_to_bin(frame_size)),
594 ts->ts_status ? "FAIL" : "OK",
595 final_rix, short_tries, long_tries);
596 update_stats(sc, an, frame_size,
597 final_rix, long_tries,
601 short_tries, long_tries, ts->ts_status);
603 int hwrate0, rix0, tries0;
604 int hwrate1, rix1, tries1;
605 int hwrate2, rix2, tries2;
606 int hwrate3, rix3, tries3;
607 int finalTSIdx = ts->ts_finaltsi;
610 * Process intermediate rates that failed.
612 if (sc->sc_ah->ah_magic != 0x20065416) {
613 hwrate0 = MS(ds0->ds_ctl3, AR_XmitRate0);
614 hwrate1 = MS(ds0->ds_ctl3, AR_XmitRate1);
615 hwrate2 = MS(ds0->ds_ctl3, AR_XmitRate2);
616 hwrate3 = MS(ds0->ds_ctl3, AR_XmitRate3);
618 hwrate0 = MS(ds0->ds_ctl3, AR5416_XmitRate0);
619 hwrate1 = MS(ds0->ds_ctl3, AR5416_XmitRate1);
620 hwrate2 = MS(ds0->ds_ctl3, AR5416_XmitRate2);
621 hwrate3 = MS(ds0->ds_ctl3, AR5416_XmitRate3);
624 rix0 = rt->rateCodeToIndex[hwrate0];
625 tries0 = MS(ds0->ds_ctl2, AR_XmitDataTries0);
627 rix1 = rt->rateCodeToIndex[hwrate1];
628 tries1 = MS(ds0->ds_ctl2, AR_XmitDataTries1);
630 rix2 = rt->rateCodeToIndex[hwrate2];
631 tries2 = MS(ds0->ds_ctl2, AR_XmitDataTries2);
633 rix3 = rt->rateCodeToIndex[hwrate3];
634 tries3 = MS(ds0->ds_ctl2, AR_XmitDataTries3);
636 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL,
638 "%s: size %d finaltsidx %d tries %d %s rate/try [%d/%d %d/%d %d/%d %d/%d]",
640 bin_to_size(size_to_bin(frame_size)),
643 ts->ts_status ? "FAIL" : "OK",
649 if (tries0 && !IS_RATE_DEFINED(sn, rix0))
650 badrate(ifp, 0, hwrate0, tries0, ts->ts_status);
651 if (tries1 && !IS_RATE_DEFINED(sn, rix1))
652 badrate(ifp, 1, hwrate1, tries1, ts->ts_status);
653 if (tries2 && !IS_RATE_DEFINED(sn, rix2))
654 badrate(ifp, 2, hwrate2, tries2, ts->ts_status);
655 if (tries3 && !IS_RATE_DEFINED(sn, rix3))
656 badrate(ifp, 3, hwrate3, tries3, ts->ts_status);
659 * NB: series > 0 are not penalized for failure
660 * based on the try counts under the assumption
661 * that losses are often bursty and since we
662 * sample higher rates 1 try at a time doing so
663 * may unfairly penalize them.
666 update_stats(sc, an, frame_size,
671 short_tries, long_tries,
672 long_tries > tries0);
673 long_tries -= tries0;
676 if (tries1 && finalTSIdx > 0) {
677 update_stats(sc, an, frame_size,
682 short_tries, long_tries,
684 long_tries -= tries1;
687 if (tries2 && finalTSIdx > 1) {
688 update_stats(sc, an, frame_size,
693 short_tries, long_tries,
695 long_tries -= tries2;
698 if (tries3 && finalTSIdx > 2) {
699 update_stats(sc, an, frame_size,
704 short_tries, long_tries,
711 ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew)
714 ath_rate_ctl_reset(sc, &an->an_node);
717 static const struct txschedule *mrr_schedules[IEEE80211_MODE_MAX+2] = {
718 NULL, /* IEEE80211_MODE_AUTO */
719 series_11a, /* IEEE80211_MODE_11A */
720 series_11g, /* IEEE80211_MODE_11B */
721 series_11g, /* IEEE80211_MODE_11G */
722 NULL, /* IEEE80211_MODE_FH */
723 series_11a, /* IEEE80211_MODE_TURBO_A */
724 series_11g, /* IEEE80211_MODE_TURBO_G */
725 series_11a, /* IEEE80211_MODE_STURBO_A */
726 series_11a, /* IEEE80211_MODE_11NA */
727 series_11g, /* IEEE80211_MODE_11NG */
728 series_half, /* IEEE80211_MODE_HALF */
729 series_quarter, /* IEEE80211_MODE_QUARTER */
733 * Initialize the tables for a node.
736 ath_rate_ctl_reset(struct ath_softc *sc, struct ieee80211_node *ni)
738 #define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL)
739 #define DOT11RATE(_ix) (rt->info[(_ix)].dot11Rate & IEEE80211_RATE_VAL)
740 struct ath_node *an = ATH_NODE(ni);
741 const struct ieee80211_txparam *tp = ni->ni_txparms;
742 struct sample_node *sn = ATH_NODE_SAMPLE(an);
743 const HAL_RATE_TABLE *rt = sc->sc_currates;
744 int x, y, srate, rix;
746 KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode));
748 KASSERT(sc->sc_curmode < IEEE80211_MODE_MAX+2,
749 ("curmode %u", sc->sc_curmode));
750 sn->sched = mrr_schedules[sc->sc_curmode];
751 KASSERT(sn->sched != NULL,
752 ("no mrr schedule for mode %u", sc->sc_curmode));
755 if (tp != NULL && tp->ucastrate != IEEE80211_FIXED_RATE_NONE) {
757 * A fixed rate is to be used; ucastrate is the IEEE code
758 * for this rate (sans basic bit). Check this against the
759 * negotiated rate set for the node. Note the fixed rate
760 * may not be available for various reasons so we only
761 * setup the static rate index if the lookup is successful.
764 for (srate = ni->ni_rates.rs_nrates - 1; srate >= 0; srate--)
765 if (RATE(srate) == tp->ucastrate) {
766 sn->static_rix = sc->sc_rixmap[tp->ucastrate];
769 #ifdef IEEE80211_DEBUG
770 if (sn->static_rix == -1) {
771 IEEE80211_NOTE(ni->ni_vap,
772 IEEE80211_MSG_RATECTL, ni,
773 "%s: ucastrate %u not found, nrates %u",
774 __func__, tp->ucastrate,
775 ni->ni_rates.rs_nrates);
781 * Construct a bitmask of usable rates. This has all
782 * negotiated rates minus those marked by the hal as
783 * to be ignored for doing rate control.
786 for (x = 0; x < ni->ni_rates.rs_nrates; x++) {
787 rix = sc->sc_rixmap[RATE(x)];
790 /* skip rates marked broken by hal */
791 if (!rt->info[rix].valid)
793 KASSERT(rix < SAMPLE_MAXRATES,
794 ("rate %u has rix %d", RATE(x), rix));
795 sn->ratemask |= 1<<rix;
797 #ifdef IEEE80211_DEBUG
798 if (ieee80211_msg(ni->ni_vap, IEEE80211_MSG_RATECTL)) {
801 ieee80211_note(ni->ni_vap, "[%6D] %s: size 1600 rate/tt",
802 ni->ni_macaddr, ":", __func__);
803 for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) {
806 printf(" %d/%d", DOT11RATE(rix) / 2,
807 calc_usecs_unicast_packet(sc, 1600, rix, 0,0));
812 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) {
813 int size = bin_to_size(y);
816 sn->packets_sent[y] = 0;
817 sn->current_sample_rix[y] = -1;
818 sn->last_sample_rix[y] = 0;
819 /* XXX start with first valid rate */
820 sn->current_rix[y] = ffs(sn->ratemask)-1;
823 * Initialize the statistics buckets; these are
824 * indexed by the rate code index.
826 for (rix = 0, mask = sn->ratemask; mask != 0; rix++, mask >>= 1) {
827 if ((mask & 1) == 0) /* not a valid rate */
829 sn->stats[y][rix].successive_failures = 0;
830 sn->stats[y][rix].tries = 0;
831 sn->stats[y][rix].total_packets = 0;
832 sn->stats[y][rix].packets_acked = 0;
833 sn->stats[y][rix].last_tx = 0;
835 sn->stats[y][rix].perfect_tx_time =
836 calc_usecs_unicast_packet(sc, size, rix, 0, 0);
837 sn->stats[y][rix].average_tx_time =
838 sn->stats[y][rix].perfect_tx_time;
842 /* XXX 0, num_rates-1 are wrong */
843 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni,
844 "%s: %d rates %d%sMbps (%dus)- %d%sMbps (%dus)", __func__,
846 DOT11RATE(0)/2, DOT11RATE(0) % 1 ? ".5" : "",
847 sn->stats[1][0].perfect_tx_time,
848 DOT11RATE(sn->num_rates-1)/2, DOT11RATE(sn->num_rates-1) % 1 ? ".5" : "",
849 sn->stats[1][sn->num_rates-1].perfect_tx_time
852 /* set the visible bit-rate */
853 if (sn->static_rix != -1)
854 ni->ni_txrate = DOT11RATE(sn->static_rix);
856 ni->ni_txrate = RATE(0);
862 sample_stats(void *arg, struct ieee80211_node *ni)
864 struct ath_softc *sc = arg;
865 const HAL_RATE_TABLE *rt = sc->sc_currates;
866 struct sample_node *sn = ATH_NODE_SAMPLE(ATH_NODE(ni));
870 printf("\n[%s] refcnt %d static_rix %d ratemask 0x%x\n",
871 ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni),
872 sn->static_rix, sn->ratemask);
873 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) {
874 printf("[%4u] cur rix %d since switch: packets %d ticks %u\n",
875 bin_to_size(y), sn->current_rix[y],
876 sn->packets_since_switch[y], sn->ticks_since_switch[y]);
877 printf("[%4u] last sample %d cur sample %d packets sent %d\n",
878 bin_to_size(y), sn->last_sample_rix[y],
879 sn->current_sample_rix[y], sn->packets_sent[y]);
880 printf("[%4u] packets since sample %d sample tt %u\n",
881 bin_to_size(y), sn->packets_since_sample[y],
884 for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) {
887 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) {
888 if (sn->stats[y][rix].total_packets == 0)
890 printf("[%2u:%4u] %8d:%-8d (%3d%%) T %8d F %4d avg %5u last %u\n",
891 (rt->info[rix].dot11Rate & IEEE80211_RATE_VAL)/2,
893 sn->stats[y][rix].total_packets,
894 sn->stats[y][rix].packets_acked,
895 (100*sn->stats[y][rix].packets_acked)/sn->stats[y][rix].total_packets,
896 sn->stats[y][rix].tries,
897 sn->stats[y][rix].successive_failures,
898 sn->stats[y][rix].average_tx_time,
899 ticks - sn->stats[y][rix].last_tx);
905 ath_rate_sysctl_stats(SYSCTL_HANDLER_ARGS)
907 struct ath_softc *sc = arg1;
908 struct ifnet *ifp = sc->sc_ifp;
909 struct ieee80211com *ic = ifp->if_l2com;
913 error = sysctl_handle_int(oidp, &v, 0, req);
914 if (error || !req->newptr)
916 ieee80211_iterate_nodes(&ic->ic_sta, sample_stats, sc);
921 ath_rate_sysctl_smoothing_rate(SYSCTL_HANDLER_ARGS)
923 struct sample_softc *ssc = arg1;
926 rate = ssc->smoothing_rate;
927 error = sysctl_handle_int(oidp, &rate, 0, req);
928 if (error || !req->newptr)
930 if (!(0 <= rate && rate < 100))
932 ssc->smoothing_rate = rate;
933 ssc->smoothing_minpackets = 100 / (100 - rate);
938 ath_rate_sysctl_sample_rate(SYSCTL_HANDLER_ARGS)
940 struct sample_softc *ssc = arg1;
943 rate = ssc->sample_rate;
944 error = sysctl_handle_int(oidp, &rate, 0, req);
945 if (error || !req->newptr)
947 if (!(2 <= rate && rate <= 100))
949 ssc->sample_rate = rate;
954 ath_rate_sysctlattach(struct ath_softc *sc, struct sample_softc *ssc)
956 struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev);
957 struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev);
959 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
960 "smoothing_rate", CTLTYPE_INT | CTLFLAG_RW, ssc, 0,
961 ath_rate_sysctl_smoothing_rate, "I",
962 "sample: smoothing rate for avg tx time (%%)");
963 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
964 "sample_rate", CTLTYPE_INT | CTLFLAG_RW, ssc, 0,
965 ath_rate_sysctl_sample_rate, "I",
966 "sample: percent air time devoted to sampling new rates (%%)");
967 /* XXX max_successive_failures, stale_failure_timeout, min_switch */
968 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
969 "sample_stats", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
970 ath_rate_sysctl_stats, "I", "sample: print statistics");
973 struct ath_ratectrl *
974 ath_rate_attach(struct ath_softc *sc)
976 struct sample_softc *ssc;
978 ssc = malloc(sizeof(struct sample_softc), M_DEVBUF, M_NOWAIT|M_ZERO);
981 ssc->arc.arc_space = sizeof(struct sample_node);
982 ssc->smoothing_rate = 95; /* ewma percentage ([0..99]) */
983 ssc->smoothing_minpackets = 100 / (100 - ssc->smoothing_rate);
984 ssc->sample_rate = 10; /* %time to try diff tx rates */
985 ssc->max_successive_failures = 3; /* threshold for rate sampling*/
986 ssc->stale_failure_timeout = 10 * hz; /* 10 seconds */
987 ssc->min_switch = hz; /* 1 second */
988 ath_rate_sysctlattach(sc, ssc);
993 ath_rate_detach(struct ath_ratectrl *arc)
995 struct sample_softc *ssc = (struct sample_softc *) arc;