1 /*-
2 * Copyright (c) 2005 John Bicket
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
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.
18 *
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.
22 *
23 * NO WARRANTY
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, MERCHANTABILITY
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.
35 *
36 */
37
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
40
41 /*
42 * John Bicket's SampleRate control algorithm.
43 */
44 #include "opt_ath.h"
45 #include "opt_inet.h"
46 #include "opt_wlan.h"
47 #include "opt_ah.h"
48
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/sysctl.h>
52 #include <sys/kernel.h>
53 #include <sys/lock.h>
54 #include <sys/malloc.h>
55 #include <sys/errno.h>
56
57 #if defined(__DragonFly__)
58 /* empty */
59 #else
60 #include <machine/bus.h>
61 #include <machine/resource.h>
62 #endif
63 #include <sys/bus.h>
64
65 #include <sys/socket.h>
66
67 #include <net/if.h>
68 #include <net/if_var.h>
69 #include <net/if_media.h>
70 #include <net/if_arp.h>
71 #include <net/ethernet.h> /* XXX for ether_sprintf */
72
73 #include <netproto/802_11/ieee80211_var.h>
74
75 #include <net/bpf.h>
76
77 #ifdef INET
78 #include <netinet/in.h>
79 #include <netinet/if_ether.h>
80 #endif
81
82 #include <dev/netif/ath/ath/if_athvar.h>
83 #include <dev/netif/ath/ath_rate/sample/sample.h>
84 #include <dev/netif/ath/ath_hal/ah_desc.h>
85 #include <dev/netif/ath/ath_rate/sample/tx_schedules.h>
86
87 #if defined(__DragonFly__)
88 extern const char* ath_hal_ether_sprintf(const uint8_t *mac);
89 #endif
90
91 /*
92 * This file is an implementation of the SampleRate algorithm
93 * in "Bit-rate Selection in Wireless Networks"
94 * (http://www.pdos.lcs.mit.edu/papers/jbicket-ms.ps)
95 *
96 * SampleRate chooses the bit-rate it predicts will provide the most
97 * throughput based on estimates of the expected per-packet
98 * transmission time for each bit-rate. SampleRate periodically sends
99 * packets at bit-rates other than the current one to estimate when
100 * another bit-rate will provide better performance. SampleRate
101 * switches to another bit-rate when its estimated per-packet
102 * transmission time becomes smaller than the current bit-rate's.
103 * SampleRate reduces the number of bit-rates it must sample by
104 * eliminating those that could not perform better than the one
105 * currently being used. SampleRate also stops probing at a bit-rate
106 * if it experiences several successive losses.
107 *
108 * The difference between the algorithm in the thesis and the one in this
109 * file is that the one in this file uses a ewma instead of a window.
110 *
111 * Also, this implementation tracks the average transmission time for
112 * a few different packet sizes independently for each link.
113 */
114
115 static void ath_rate_ctl_reset(struct ath_softc *, struct ieee80211_node *);
116
117 static __inline int
size_to_bin(int size)118 size_to_bin(int size)
119 {
120 #if NUM_PACKET_SIZE_BINS > 1
121 if (size <= packet_size_bins[0])
122 return 0;
123 #endif
124 #if NUM_PACKET_SIZE_BINS > 2
125 if (size <= packet_size_bins[1])
126 return 1;
127 #endif
128 #if NUM_PACKET_SIZE_BINS > 3
129 if (size <= packet_size_bins[2])
130 return 2;
131 #endif
132 #if NUM_PACKET_SIZE_BINS > 4
133 #error "add support for more packet sizes"
134 #endif
135 return NUM_PACKET_SIZE_BINS-1;
136 }
137
138 void
ath_rate_node_init(struct ath_softc * sc,struct ath_node * an)139 ath_rate_node_init(struct ath_softc *sc, struct ath_node *an)
140 {
141 /* NB: assumed to be zero'd by caller */
142 }
143
144 void
ath_rate_node_cleanup(struct ath_softc * sc,struct ath_node * an)145 ath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an)
146 {
147 }
148
149 static int
dot11rate(const HAL_RATE_TABLE * rt,int rix)150 dot11rate(const HAL_RATE_TABLE *rt, int rix)
151 {
152 if (rix < 0)
153 return -1;
154 return rt->info[rix].phy == IEEE80211_T_HT ?
155 rt->info[rix].dot11Rate : (rt->info[rix].dot11Rate & IEEE80211_RATE_VAL) / 2;
156 }
157
158 static const char *
dot11rate_label(const HAL_RATE_TABLE * rt,int rix)159 dot11rate_label(const HAL_RATE_TABLE *rt, int rix)
160 {
161 if (rix < 0)
162 return "";
163 return rt->info[rix].phy == IEEE80211_T_HT ? "MCS" : "Mb ";
164 }
165
166 /*
167 * Return the rix with the lowest average_tx_time,
168 * or -1 if all the average_tx_times are 0.
169 */
170 static __inline int
pick_best_rate(struct ath_node * an,const HAL_RATE_TABLE * rt,int size_bin,int require_acked_before)171 pick_best_rate(struct ath_node *an, const HAL_RATE_TABLE *rt,
172 int size_bin, int require_acked_before)
173 {
174 struct sample_node *sn = ATH_NODE_SAMPLE(an);
175 int best_rate_rix, best_rate_tt, best_rate_pct;
176 uint64_t mask;
177 int rix, tt, pct;
178
179 best_rate_rix = 0;
180 best_rate_tt = 0;
181 best_rate_pct = 0;
182 for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) {
183 if ((mask & 1) == 0) /* not a supported rate */
184 continue;
185
186 /* Don't pick a non-HT rate for a HT node */
187 if ((an->an_node.ni_flags & IEEE80211_NODE_HT) &&
188 (rt->info[rix].phy != IEEE80211_T_HT)) {
189 continue;
190 }
191
192 tt = sn->stats[size_bin][rix].average_tx_time;
193 if (tt <= 0 ||
194 (require_acked_before &&
195 !sn->stats[size_bin][rix].packets_acked))
196 continue;
197
198 /* Calculate percentage if possible */
199 if (sn->stats[size_bin][rix].total_packets > 0) {
200 pct = sn->stats[size_bin][rix].ewma_pct;
201 } else {
202 /* XXX for now, assume 95% ok */
203 pct = 95;
204 }
205
206 /* don't use a bit-rate that has been failing */
207 if (sn->stats[size_bin][rix].successive_failures > 3)
208 continue;
209
210 /*
211 * For HT, Don't use a bit rate that is much more
212 * lossy than the best.
213 *
214 * XXX this isn't optimal; it's just designed to
215 * eliminate rates that are going to be obviously
216 * worse.
217 */
218 if (an->an_node.ni_flags & IEEE80211_NODE_HT) {
219 if (best_rate_pct > (pct + 50))
220 continue;
221 }
222
223 /*
224 * For non-MCS rates, use the current average txtime for
225 * comparison.
226 */
227 if (! (an->an_node.ni_flags & IEEE80211_NODE_HT)) {
228 if (best_rate_tt == 0 || tt <= best_rate_tt) {
229 best_rate_tt = tt;
230 best_rate_rix = rix;
231 best_rate_pct = pct;
232 }
233 }
234
235 /*
236 * Since 2 stream rates have slightly higher TX times,
237 * allow a little bit of leeway. This should later
238 * be abstracted out and properly handled.
239 */
240 if (an->an_node.ni_flags & IEEE80211_NODE_HT) {
241 if (best_rate_tt == 0 || (tt * 8 <= best_rate_tt * 10)) {
242 best_rate_tt = tt;
243 best_rate_rix = rix;
244 best_rate_pct = pct;
245 }
246 }
247 }
248 return (best_rate_tt ? best_rate_rix : -1);
249 }
250
251 /*
252 * Pick a good "random" bit-rate to sample other than the current one.
253 */
254 static __inline int
pick_sample_rate(struct sample_softc * ssc,struct ath_node * an,const HAL_RATE_TABLE * rt,int size_bin)255 pick_sample_rate(struct sample_softc *ssc , struct ath_node *an,
256 const HAL_RATE_TABLE *rt, int size_bin)
257 {
258 #define DOT11RATE(ix) (rt->info[ix].dot11Rate & IEEE80211_RATE_VAL)
259 #define MCS(ix) (rt->info[ix].dot11Rate | IEEE80211_RATE_MCS)
260 struct sample_node *sn = ATH_NODE_SAMPLE(an);
261 int current_rix, rix;
262 unsigned current_tt;
263 uint64_t mask;
264
265 current_rix = sn->current_rix[size_bin];
266 if (current_rix < 0) {
267 /* no successes yet, send at the lowest bit-rate */
268 /* XXX should return MCS0 if HT */
269 return 0;
270 }
271
272 current_tt = sn->stats[size_bin][current_rix].average_tx_time;
273
274 rix = sn->last_sample_rix[size_bin]+1; /* next sample rate */
275 mask = sn->ratemask &~ ((uint64_t) 1<<current_rix);/* don't sample current rate */
276 while (mask != 0) {
277 if ((mask & ((uint64_t) 1<<rix)) == 0) { /* not a supported rate */
278 nextrate:
279 if (++rix >= rt->rateCount)
280 rix = 0;
281 continue;
282 }
283
284 /*
285 * The following code stops trying to sample
286 * non-MCS rates when speaking to an MCS node.
287 * However, at least for CCK rates in 2.4GHz mode,
288 * the non-MCS rates MAY actually provide better
289 * PER at the very far edge of reception.
290 *
291 * However! Until ath_rate_form_aggr() grows
292 * some logic to not form aggregates if the
293 * selected rate is non-MCS, this won't work.
294 *
295 * So don't disable this code until you've taught
296 * ath_rate_form_aggr() to drop out if any of
297 * the selected rates are non-MCS.
298 */
299 #if 1
300 /* if the node is HT and the rate isn't HT, don't bother sample */
301 if ((an->an_node.ni_flags & IEEE80211_NODE_HT) &&
302 (rt->info[rix].phy != IEEE80211_T_HT)) {
303 mask &= ~((uint64_t) 1<<rix);
304 goto nextrate;
305 }
306 #endif
307
308 /* this bit-rate is always worse than the current one */
309 if (sn->stats[size_bin][rix].perfect_tx_time > current_tt) {
310 mask &= ~((uint64_t) 1<<rix);
311 goto nextrate;
312 }
313
314 /* rarely sample bit-rates that fail a lot */
315 if (sn->stats[size_bin][rix].successive_failures > ssc->max_successive_failures &&
316 ticks - sn->stats[size_bin][rix].last_tx < ssc->stale_failure_timeout) {
317 mask &= ~((uint64_t) 1<<rix);
318 goto nextrate;
319 }
320
321 /*
322 * For HT, only sample a few rates on either side of the
323 * current rix; there's quite likely a lot of them.
324 */
325 if (an->an_node.ni_flags & IEEE80211_NODE_HT) {
326 if (rix < (current_rix - 3) ||
327 rix > (current_rix + 3)) {
328 mask &= ~((uint64_t) 1<<rix);
329 goto nextrate;
330 }
331 }
332
333 /* Don't sample more than 2 rates higher for rates > 11M for non-HT rates */
334 if (! (an->an_node.ni_flags & IEEE80211_NODE_HT)) {
335 if (DOT11RATE(rix) > 2*11 && rix > current_rix + 2) {
336 mask &= ~((uint64_t) 1<<rix);
337 goto nextrate;
338 }
339 }
340
341 sn->last_sample_rix[size_bin] = rix;
342 return rix;
343 }
344 return current_rix;
345 #undef DOT11RATE
346 #undef MCS
347 }
348
349 static int
ath_rate_get_static_rix(struct ath_softc * sc,const struct ieee80211_node * ni)350 ath_rate_get_static_rix(struct ath_softc *sc, const struct ieee80211_node *ni)
351 {
352 #define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL)
353 #define DOT11RATE(_ix) (rt->info[(_ix)].dot11Rate & IEEE80211_RATE_VAL)
354 #define MCS(_ix) (ni->ni_htrates.rs_rates[_ix] | IEEE80211_RATE_MCS)
355 const struct ieee80211_txparam *tp = ni->ni_txparms;
356 int srate;
357
358 /* Check MCS rates */
359 for (srate = ni->ni_htrates.rs_nrates - 1; srate >= 0; srate--) {
360 if (MCS(srate) == tp->ucastrate)
361 return sc->sc_rixmap[tp->ucastrate];
362 }
363
364 /* Check legacy rates */
365 for (srate = ni->ni_rates.rs_nrates - 1; srate >= 0; srate--) {
366 if (RATE(srate) == tp->ucastrate)
367 return sc->sc_rixmap[tp->ucastrate];
368 }
369 return -1;
370 #undef RATE
371 #undef DOT11RATE
372 #undef MCS
373 }
374
375 static void
ath_rate_update_static_rix(struct ath_softc * sc,struct ieee80211_node * ni)376 ath_rate_update_static_rix(struct ath_softc *sc, struct ieee80211_node *ni)
377 {
378 struct ath_node *an = ATH_NODE(ni);
379 const struct ieee80211_txparam *tp = ni->ni_txparms;
380 struct sample_node *sn = ATH_NODE_SAMPLE(an);
381
382 if (tp != NULL && tp->ucastrate != IEEE80211_FIXED_RATE_NONE) {
383 /*
384 * A fixed rate is to be used; ucastrate is the IEEE code
385 * for this rate (sans basic bit). Check this against the
386 * negotiated rate set for the node. Note the fixed rate
387 * may not be available for various reasons so we only
388 * setup the static rate index if the lookup is successful.
389 */
390 sn->static_rix = ath_rate_get_static_rix(sc, ni);
391 } else {
392 sn->static_rix = -1;
393 }
394 }
395
396 /*
397 * Pick a non-HT rate to begin using.
398 */
399 static int
ath_rate_pick_seed_rate_legacy(struct ath_softc * sc,struct ath_node * an,int frameLen)400 ath_rate_pick_seed_rate_legacy(struct ath_softc *sc, struct ath_node *an,
401 int frameLen)
402 {
403 #define DOT11RATE(ix) (rt->info[ix].dot11Rate & IEEE80211_RATE_VAL)
404 #define MCS(ix) (rt->info[ix].dot11Rate | IEEE80211_RATE_MCS)
405 #define RATE(ix) (DOT11RATE(ix) / 2)
406 int rix = -1;
407 const HAL_RATE_TABLE *rt = sc->sc_currates;
408 struct sample_node *sn = ATH_NODE_SAMPLE(an);
409 const int size_bin = size_to_bin(frameLen);
410
411 /* no packet has been sent successfully yet */
412 for (rix = rt->rateCount-1; rix > 0; rix--) {
413 if ((sn->ratemask & ((uint64_t) 1<<rix)) == 0)
414 continue;
415
416 /* Skip HT rates */
417 if (rt->info[rix].phy == IEEE80211_T_HT)
418 continue;
419
420 /*
421 * Pick the highest rate <= 36 Mbps
422 * that hasn't failed.
423 */
424 if (DOT11RATE(rix) <= 72 &&
425 sn->stats[size_bin][rix].successive_failures == 0) {
426 break;
427 }
428 }
429 return rix;
430 #undef RATE
431 #undef MCS
432 #undef DOT11RATE
433 }
434
435 /*
436 * Pick a HT rate to begin using.
437 *
438 * Don't use any non-HT rates; only consider HT rates.
439 */
440 static int
ath_rate_pick_seed_rate_ht(struct ath_softc * sc,struct ath_node * an,int frameLen)441 ath_rate_pick_seed_rate_ht(struct ath_softc *sc, struct ath_node *an,
442 int frameLen)
443 {
444 #define DOT11RATE(ix) (rt->info[ix].dot11Rate & IEEE80211_RATE_VAL)
445 #define MCS(ix) (rt->info[ix].dot11Rate | IEEE80211_RATE_MCS)
446 #define RATE(ix) (DOT11RATE(ix) / 2)
447 int rix = -1, ht_rix = -1;
448 const HAL_RATE_TABLE *rt = sc->sc_currates;
449 struct sample_node *sn = ATH_NODE_SAMPLE(an);
450 const int size_bin = size_to_bin(frameLen);
451
452 /* no packet has been sent successfully yet */
453 for (rix = rt->rateCount-1; rix > 0; rix--) {
454 /* Skip rates we can't use */
455 if ((sn->ratemask & ((uint64_t) 1<<rix)) == 0)
456 continue;
457
458 /* Keep a copy of the last seen HT rate index */
459 if (rt->info[rix].phy == IEEE80211_T_HT)
460 ht_rix = rix;
461
462 /* Skip non-HT rates */
463 if (rt->info[rix].phy != IEEE80211_T_HT)
464 continue;
465
466 /*
467 * Pick a medium-speed rate regardless of stream count
468 * which has not seen any failures. Higher rates may fail;
469 * we'll try them later.
470 */
471 if (((MCS(rix) & 0x7) <= 4) &&
472 sn->stats[size_bin][rix].successive_failures == 0) {
473 break;
474 }
475 }
476
477 /*
478 * If all the MCS rates have successive failures, rix should be
479 * > 0; otherwise use the lowest MCS rix (hopefully MCS 0.)
480 */
481 return MAX(rix, ht_rix);
482 #undef RATE
483 #undef MCS
484 #undef DOT11RATE
485 }
486
487
488 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)489 ath_rate_findrate(struct ath_softc *sc, struct ath_node *an,
490 int shortPreamble, size_t frameLen,
491 u_int8_t *rix0, int *try0, u_int8_t *txrate)
492 {
493 #define DOT11RATE(ix) (rt->info[ix].dot11Rate & IEEE80211_RATE_VAL)
494 #define MCS(ix) (rt->info[ix].dot11Rate | IEEE80211_RATE_MCS)
495 #define RATE(ix) (DOT11RATE(ix) / 2)
496 struct sample_node *sn = ATH_NODE_SAMPLE(an);
497 struct sample_softc *ssc = ATH_SOFTC_SAMPLE(sc);
498 struct ieee80211com *ic = &sc->sc_ic;
499 const HAL_RATE_TABLE *rt = sc->sc_currates;
500 const int size_bin = size_to_bin(frameLen);
501 int rix, mrr, best_rix, change_rates;
502 unsigned average_tx_time;
503
504 ath_rate_update_static_rix(sc, &an->an_node);
505
506 if (sn->currates != sc->sc_currates) {
507 device_printf(sc->sc_dev, "%s: currates != sc_currates!\n",
508 __func__);
509 rix = 0;
510 *try0 = ATH_TXMAXTRY;
511 goto done;
512 }
513
514 if (sn->static_rix != -1) {
515 rix = sn->static_rix;
516 *try0 = ATH_TXMAXTRY;
517 goto done;
518 }
519
520 mrr = sc->sc_mrretry;
521 /* XXX check HT protmode too */
522 if (mrr && (ic->ic_flags & IEEE80211_F_USEPROT && !sc->sc_mrrprot))
523 mrr = 0;
524
525 best_rix = pick_best_rate(an, rt, size_bin, !mrr);
526 if (best_rix >= 0) {
527 average_tx_time = sn->stats[size_bin][best_rix].average_tx_time;
528 } else {
529 average_tx_time = 0;
530 }
531 /*
532 * Limit the time measuring the performance of other tx
533 * rates to sample_rate% of the total transmission time.
534 */
535 if (sn->sample_tt[size_bin] < average_tx_time * (sn->packets_since_sample[size_bin]*ssc->sample_rate/100)) {
536 rix = pick_sample_rate(ssc, an, rt, size_bin);
537 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL,
538 &an->an_node, "att %d sample_tt %d size %u sample rate %d %s current rate %d %s",
539 average_tx_time,
540 sn->sample_tt[size_bin],
541 bin_to_size(size_bin),
542 dot11rate(rt, rix),
543 dot11rate_label(rt, rix),
544 dot11rate(rt, sn->current_rix[size_bin]),
545 dot11rate_label(rt, sn->current_rix[size_bin]));
546 if (rix != sn->current_rix[size_bin]) {
547 sn->current_sample_rix[size_bin] = rix;
548 } else {
549 sn->current_sample_rix[size_bin] = -1;
550 }
551 sn->packets_since_sample[size_bin] = 0;
552 } else {
553 change_rates = 0;
554 if (!sn->packets_sent[size_bin] || best_rix == -1) {
555 /* no packet has been sent successfully yet */
556 change_rates = 1;
557 if (an->an_node.ni_flags & IEEE80211_NODE_HT)
558 best_rix =
559 ath_rate_pick_seed_rate_ht(sc, an, frameLen);
560 else
561 best_rix =
562 ath_rate_pick_seed_rate_legacy(sc, an, frameLen);
563 } else if (sn->packets_sent[size_bin] < 20) {
564 /* let the bit-rate switch quickly during the first few packets */
565 IEEE80211_NOTE(an->an_node.ni_vap,
566 IEEE80211_MSG_RATECTL, &an->an_node,
567 "%s: switching quickly..", __func__);
568 change_rates = 1;
569 } else if (ticks - ssc->min_switch > sn->ticks_since_switch[size_bin]) {
570 /* min_switch seconds have gone by */
571 IEEE80211_NOTE(an->an_node.ni_vap,
572 IEEE80211_MSG_RATECTL, &an->an_node,
573 "%s: min_switch %d > ticks_since_switch %d..",
574 __func__, ticks - ssc->min_switch, sn->ticks_since_switch[size_bin]);
575 change_rates = 1;
576 } else if ((! (an->an_node.ni_flags & IEEE80211_NODE_HT)) &&
577 (2*average_tx_time < sn->stats[size_bin][sn->current_rix[size_bin]].average_tx_time)) {
578 /* the current bit-rate is twice as slow as the best one */
579 IEEE80211_NOTE(an->an_node.ni_vap,
580 IEEE80211_MSG_RATECTL, &an->an_node,
581 "%s: 2x att (= %d) < cur_rix att %d",
582 __func__,
583 2 * average_tx_time, sn->stats[size_bin][sn->current_rix[size_bin]].average_tx_time);
584 change_rates = 1;
585 } else if ((an->an_node.ni_flags & IEEE80211_NODE_HT)) {
586 int cur_rix = sn->current_rix[size_bin];
587 int cur_att = sn->stats[size_bin][cur_rix].average_tx_time;
588 /*
589 * If the node is HT, upgrade it if the MCS rate is
590 * higher and the average tx time is within 20% of
591 * the current rate. It can fail a little.
592 *
593 * This is likely not optimal!
594 */
595 #if 0
596 kprintf("cur rix/att %x/%d, best rix/att %x/%d\n",
597 MCS(cur_rix), cur_att, MCS(best_rix), average_tx_time);
598 #endif
599 if ((MCS(best_rix) > MCS(cur_rix)) &&
600 (average_tx_time * 8) <= (cur_att * 10)) {
601 IEEE80211_NOTE(an->an_node.ni_vap,
602 IEEE80211_MSG_RATECTL, &an->an_node,
603 "%s: HT: best_rix 0x%d > cur_rix 0x%x, average_tx_time %d, cur_att %d",
604 __func__,
605 MCS(best_rix), MCS(cur_rix), average_tx_time, cur_att);
606 change_rates = 1;
607 }
608 }
609
610 sn->packets_since_sample[size_bin]++;
611
612 if (change_rates) {
613 if (best_rix != sn->current_rix[size_bin]) {
614 IEEE80211_NOTE(an->an_node.ni_vap,
615 IEEE80211_MSG_RATECTL,
616 &an->an_node,
617 "%s: size %d switch rate %d (%d/%d) -> %d (%d/%d) after %d packets mrr %d",
618 __func__,
619 bin_to_size(size_bin),
620 RATE(sn->current_rix[size_bin]),
621 sn->stats[size_bin][sn->current_rix[size_bin]].average_tx_time,
622 sn->stats[size_bin][sn->current_rix[size_bin]].perfect_tx_time,
623 RATE(best_rix),
624 sn->stats[size_bin][best_rix].average_tx_time,
625 sn->stats[size_bin][best_rix].perfect_tx_time,
626 sn->packets_since_switch[size_bin],
627 mrr);
628 }
629 sn->packets_since_switch[size_bin] = 0;
630 sn->current_rix[size_bin] = best_rix;
631 sn->ticks_since_switch[size_bin] = ticks;
632 /*
633 * Set the visible txrate for this node.
634 */
635 an->an_node.ni_txrate = (rt->info[best_rix].phy == IEEE80211_T_HT) ? MCS(best_rix) : DOT11RATE(best_rix);
636 }
637 rix = sn->current_rix[size_bin];
638 sn->packets_since_switch[size_bin]++;
639 }
640 *try0 = mrr ? sn->sched[rix].t0 : ATH_TXMAXTRY;
641 done:
642
643 /*
644 * This bug totally sucks and should be fixed.
645 *
646 * For now though, let's not panic, so we can start to figure
647 * out how to better reproduce it.
648 */
649 if (rix < 0 || rix >= rt->rateCount) {
650 kprintf("%s: ERROR: rix %d out of bounds (rateCount=%d)\n",
651 __func__,
652 rix,
653 rt->rateCount);
654 rix = 0; /* XXX just default for now */
655 }
656 KASSERT(rix >= 0 && rix < rt->rateCount, ("rix is %d", rix));
657
658 *rix0 = rix;
659 *txrate = rt->info[rix].rateCode
660 | (shortPreamble ? rt->info[rix].shortPreamble : 0);
661 sn->packets_sent[size_bin]++;
662 #undef DOT11RATE
663 #undef MCS
664 #undef RATE
665 }
666
667 /*
668 * Get the TX rates. Don't fiddle with short preamble flags for them;
669 * the caller can do that.
670 */
671 void
ath_rate_getxtxrates(struct ath_softc * sc,struct ath_node * an,uint8_t rix0,struct ath_rc_series * rc)672 ath_rate_getxtxrates(struct ath_softc *sc, struct ath_node *an,
673 uint8_t rix0, struct ath_rc_series *rc)
674 {
675 struct sample_node *sn = ATH_NODE_SAMPLE(an);
676 const struct txschedule *sched = &sn->sched[rix0];
677
678 KASSERT(rix0 == sched->r0, ("rix0 (%x) != sched->r0 (%x)!\n",
679 rix0, sched->r0));
680
681 rc[0].flags = rc[1].flags = rc[2].flags = rc[3].flags = 0;
682
683 rc[0].rix = sched->r0;
684 rc[1].rix = sched->r1;
685 rc[2].rix = sched->r2;
686 rc[3].rix = sched->r3;
687
688 rc[0].tries = sched->t0;
689 rc[1].tries = sched->t1;
690 rc[2].tries = sched->t2;
691 rc[3].tries = sched->t3;
692 }
693
694 void
ath_rate_setupxtxdesc(struct ath_softc * sc,struct ath_node * an,struct ath_desc * ds,int shortPreamble,u_int8_t rix)695 ath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an,
696 struct ath_desc *ds, int shortPreamble, u_int8_t rix)
697 {
698 struct sample_node *sn = ATH_NODE_SAMPLE(an);
699 const struct txschedule *sched = &sn->sched[rix];
700 const HAL_RATE_TABLE *rt = sc->sc_currates;
701 uint8_t rix1, s1code, rix2, s2code, rix3, s3code;
702
703 /* XXX precalculate short preamble tables */
704 rix1 = sched->r1;
705 s1code = rt->info[rix1].rateCode
706 | (shortPreamble ? rt->info[rix1].shortPreamble : 0);
707 rix2 = sched->r2;
708 s2code = rt->info[rix2].rateCode
709 | (shortPreamble ? rt->info[rix2].shortPreamble : 0);
710 rix3 = sched->r3;
711 s3code = rt->info[rix3].rateCode
712 | (shortPreamble ? rt->info[rix3].shortPreamble : 0);
713 ath_hal_setupxtxdesc(sc->sc_ah, ds,
714 s1code, sched->t1, /* series 1 */
715 s2code, sched->t2, /* series 2 */
716 s3code, sched->t3); /* series 3 */
717 }
718
719 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)720 update_stats(struct ath_softc *sc, struct ath_node *an,
721 int frame_size,
722 int rix0, int tries0,
723 int rix1, int tries1,
724 int rix2, int tries2,
725 int rix3, int tries3,
726 int short_tries, int tries, int status,
727 int nframes, int nbad)
728 {
729 struct sample_node *sn = ATH_NODE_SAMPLE(an);
730 struct sample_softc *ssc = ATH_SOFTC_SAMPLE(sc);
731 #ifdef IEEE80211_DEBUG
732 const HAL_RATE_TABLE *rt = sc->sc_currates;
733 #endif
734 const int size_bin = size_to_bin(frame_size);
735 const int size = bin_to_size(size_bin);
736 int tt, tries_so_far;
737 int is_ht40 = (an->an_node.ni_chw == 40);
738 int pct;
739
740 if (!IS_RATE_DEFINED(sn, rix0))
741 return;
742 tt = calc_usecs_unicast_packet(sc, size, rix0, short_tries,
743 MIN(tries0, tries) - 1, is_ht40);
744 tries_so_far = tries0;
745
746 if (tries1 && tries_so_far < tries) {
747 if (!IS_RATE_DEFINED(sn, rix1))
748 return;
749 tt += calc_usecs_unicast_packet(sc, size, rix1, short_tries,
750 MIN(tries1 + tries_so_far, tries) - tries_so_far - 1, is_ht40);
751 tries_so_far += tries1;
752 }
753
754 if (tries2 && tries_so_far < tries) {
755 if (!IS_RATE_DEFINED(sn, rix2))
756 return;
757 tt += calc_usecs_unicast_packet(sc, size, rix2, short_tries,
758 MIN(tries2 + tries_so_far, tries) - tries_so_far - 1, is_ht40);
759 tries_so_far += tries2;
760 }
761
762 if (tries3 && tries_so_far < tries) {
763 if (!IS_RATE_DEFINED(sn, rix3))
764 return;
765 tt += calc_usecs_unicast_packet(sc, size, rix3, short_tries,
766 MIN(tries3 + tries_so_far, tries) - tries_so_far - 1, is_ht40);
767 }
768
769 if (sn->stats[size_bin][rix0].total_packets < ssc->smoothing_minpackets) {
770 /* just average the first few packets */
771 int avg_tx = sn->stats[size_bin][rix0].average_tx_time;
772 int packets = sn->stats[size_bin][rix0].total_packets;
773 sn->stats[size_bin][rix0].average_tx_time = (tt+(avg_tx*packets))/(packets+nframes);
774 } else {
775 /* use a ewma */
776 sn->stats[size_bin][rix0].average_tx_time =
777 ((sn->stats[size_bin][rix0].average_tx_time * ssc->smoothing_rate) +
778 (tt * (100 - ssc->smoothing_rate))) / 100;
779 }
780
781 /*
782 * XXX Don't mark the higher bit rates as also having failed; as this
783 * unfortunately stops those rates from being tasted when trying to
784 * TX. This happens with 11n aggregation.
785 */
786 if (nframes == nbad) {
787 #if 0
788 int y;
789 #endif
790 sn->stats[size_bin][rix0].successive_failures += nbad;
791 #if 0
792 for (y = size_bin+1; y < NUM_PACKET_SIZE_BINS; y++) {
793 /*
794 * Also say larger packets failed since we
795 * assume if a small packet fails at a
796 * bit-rate then a larger one will also.
797 */
798 sn->stats[y][rix0].successive_failures += nbad;
799 sn->stats[y][rix0].last_tx = ticks;
800 sn->stats[y][rix0].tries += tries;
801 sn->stats[y][rix0].total_packets += nframes;
802 }
803 #endif
804 } else {
805 sn->stats[size_bin][rix0].packets_acked += (nframes - nbad);
806 sn->stats[size_bin][rix0].successive_failures = 0;
807 }
808 sn->stats[size_bin][rix0].tries += tries;
809 sn->stats[size_bin][rix0].last_tx = ticks;
810 sn->stats[size_bin][rix0].total_packets += nframes;
811
812 /* update EWMA for this rix */
813
814 /* Calculate percentage based on current rate */
815 if (nframes == 0)
816 nframes = nbad = 1;
817 pct = ((nframes - nbad) * 1000) / nframes;
818
819 if (sn->stats[size_bin][rix0].total_packets <
820 ssc->smoothing_minpackets) {
821 /* just average the first few packets */
822 int a_pct = (sn->stats[size_bin][rix0].packets_acked * 1000) /
823 (sn->stats[size_bin][rix0].total_packets);
824 sn->stats[size_bin][rix0].ewma_pct = a_pct;
825 } else {
826 /* use a ewma */
827 sn->stats[size_bin][rix0].ewma_pct =
828 ((sn->stats[size_bin][rix0].ewma_pct * ssc->smoothing_rate) +
829 (pct * (100 - ssc->smoothing_rate))) / 100;
830 }
831
832
833 if (rix0 == sn->current_sample_rix[size_bin]) {
834 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL,
835 &an->an_node,
836 "%s: size %d %s sample rate %d %s tries (%d/%d) tt %d avg_tt (%d/%d) nfrm %d nbad %d",
837 __func__,
838 size,
839 status ? "FAIL" : "OK",
840 dot11rate(rt, rix0),
841 dot11rate_label(rt, rix0),
842 short_tries, tries, tt,
843 sn->stats[size_bin][rix0].average_tx_time,
844 sn->stats[size_bin][rix0].perfect_tx_time,
845 nframes, nbad);
846 sn->sample_tt[size_bin] = tt;
847 sn->current_sample_rix[size_bin] = -1;
848 }
849 }
850
851 static void
badrate(struct ath_softc * sc,int series,int hwrate,int tries,int status)852 badrate(struct ath_softc *sc, int series, int hwrate, int tries, int status)
853 {
854
855 device_printf(sc->sc_dev,
856 "bad series%d hwrate 0x%x, tries %u ts_status 0x%x\n",
857 series, hwrate, tries, status);
858 }
859
860 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)861 ath_rate_tx_complete(struct ath_softc *sc, struct ath_node *an,
862 const struct ath_rc_series *rc, const struct ath_tx_status *ts,
863 int frame_size, int nframes, int nbad)
864 {
865 struct ieee80211com *ic = &sc->sc_ic;
866 struct sample_node *sn = ATH_NODE_SAMPLE(an);
867 int final_rix, short_tries, long_tries;
868 const HAL_RATE_TABLE *rt = sc->sc_currates;
869 int status = ts->ts_status;
870 int mrr;
871
872 final_rix = rt->rateCodeToIndex[ts->ts_rate];
873 short_tries = ts->ts_shortretry;
874 long_tries = ts->ts_longretry + 1;
875
876 if (nframes == 0) {
877 device_printf(sc->sc_dev, "%s: nframes=0?\n", __func__);
878 return;
879 }
880
881 if (frame_size == 0) /* NB: should not happen */
882 frame_size = 1500;
883
884 if (sn->ratemask == 0) {
885 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL,
886 &an->an_node,
887 "%s: size %d %s rate/try %d/%d no rates yet",
888 __func__,
889 bin_to_size(size_to_bin(frame_size)),
890 status ? "FAIL" : "OK",
891 short_tries, long_tries);
892 return;
893 }
894 mrr = sc->sc_mrretry;
895 /* XXX check HT protmode too */
896 if (mrr && (ic->ic_flags & IEEE80211_F_USEPROT && !sc->sc_mrrprot))
897 mrr = 0;
898
899 if (!mrr || ts->ts_finaltsi == 0) {
900 if (!IS_RATE_DEFINED(sn, final_rix)) {
901 device_printf(sc->sc_dev,
902 "%s: ts_rate=%d ts_finaltsi=%d, final_rix=%d\n",
903 __func__, ts->ts_rate, ts->ts_finaltsi, final_rix);
904 badrate(sc, 0, ts->ts_rate, long_tries, status);
905 return;
906 }
907 /*
908 * Only one rate was used; optimize work.
909 */
910 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL,
911 &an->an_node, "%s: size %d (%d bytes) %s rate/short/long %d %s/%d/%d nframes/nbad [%d/%d]",
912 __func__,
913 bin_to_size(size_to_bin(frame_size)),
914 frame_size,
915 status ? "FAIL" : "OK",
916 dot11rate(rt, final_rix), dot11rate_label(rt, final_rix),
917 short_tries, long_tries, nframes, nbad);
918 update_stats(sc, an, frame_size,
919 final_rix, long_tries,
920 0, 0,
921 0, 0,
922 0, 0,
923 short_tries, long_tries, status,
924 nframes, nbad);
925
926 } else {
927 int finalTSIdx = ts->ts_finaltsi;
928 int i;
929
930 /*
931 * Process intermediate rates that failed.
932 */
933
934 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL,
935 &an->an_node,
936 "%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]",
937 __func__,
938 bin_to_size(size_to_bin(frame_size)),
939 frame_size,
940 finalTSIdx,
941 short_tries,
942 long_tries,
943 status ? "FAIL" : "OK",
944 dot11rate(rt, rc[0].rix),
945 dot11rate_label(rt, rc[0].rix), rc[0].tries,
946 dot11rate(rt, rc[1].rix),
947 dot11rate_label(rt, rc[1].rix), rc[1].tries,
948 dot11rate(rt, rc[2].rix),
949 dot11rate_label(rt, rc[2].rix), rc[2].tries,
950 dot11rate(rt, rc[3].rix),
951 dot11rate_label(rt, rc[3].rix), rc[3].tries,
952 nframes, nbad);
953
954 for (i = 0; i < 4; i++) {
955 if (rc[i].tries && !IS_RATE_DEFINED(sn, rc[i].rix))
956 badrate(sc, 0, rc[i].ratecode, rc[i].tries,
957 status);
958 }
959
960 /*
961 * NB: series > 0 are not penalized for failure
962 * based on the try counts under the assumption
963 * that losses are often bursty and since we
964 * sample higher rates 1 try at a time doing so
965 * may unfairly penalize them.
966 */
967 if (rc[0].tries) {
968 update_stats(sc, an, frame_size,
969 rc[0].rix, rc[0].tries,
970 rc[1].rix, rc[1].tries,
971 rc[2].rix, rc[2].tries,
972 rc[3].rix, rc[3].tries,
973 short_tries, long_tries,
974 long_tries > rc[0].tries,
975 nframes, nbad);
976 long_tries -= rc[0].tries;
977 }
978
979 if (rc[1].tries && finalTSIdx > 0) {
980 update_stats(sc, an, frame_size,
981 rc[1].rix, rc[1].tries,
982 rc[2].rix, rc[2].tries,
983 rc[3].rix, rc[3].tries,
984 0, 0,
985 short_tries, long_tries,
986 status,
987 nframes, nbad);
988 long_tries -= rc[1].tries;
989 }
990
991 if (rc[2].tries && finalTSIdx > 1) {
992 update_stats(sc, an, frame_size,
993 rc[2].rix, rc[2].tries,
994 rc[3].rix, rc[3].tries,
995 0, 0,
996 0, 0,
997 short_tries, long_tries,
998 status,
999 nframes, nbad);
1000 long_tries -= rc[2].tries;
1001 }
1002
1003 if (rc[3].tries && finalTSIdx > 2) {
1004 update_stats(sc, an, frame_size,
1005 rc[3].rix, rc[3].tries,
1006 0, 0,
1007 0, 0,
1008 0, 0,
1009 short_tries, long_tries,
1010 status,
1011 nframes, nbad);
1012 }
1013 }
1014 }
1015
1016 void
ath_rate_newassoc(struct ath_softc * sc,struct ath_node * an,int isnew)1017 ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew)
1018 {
1019 if (isnew)
1020 ath_rate_ctl_reset(sc, &an->an_node);
1021 }
1022
1023 static const struct txschedule *mrr_schedules[IEEE80211_MODE_MAX+2] = {
1024 NULL, /* IEEE80211_MODE_AUTO */
1025 series_11a, /* IEEE80211_MODE_11A */
1026 series_11g, /* IEEE80211_MODE_11B */
1027 series_11g, /* IEEE80211_MODE_11G */
1028 NULL, /* IEEE80211_MODE_FH */
1029 series_11a, /* IEEE80211_MODE_TURBO_A */
1030 series_11g, /* IEEE80211_MODE_TURBO_G */
1031 series_11a, /* IEEE80211_MODE_STURBO_A */
1032 series_11na, /* IEEE80211_MODE_11NA */
1033 series_11ng, /* IEEE80211_MODE_11NG */
1034 series_half, /* IEEE80211_MODE_HALF */
1035 series_quarter, /* IEEE80211_MODE_QUARTER */
1036 };
1037
1038 /*
1039 * Initialize the tables for a node.
1040 */
1041 static void
ath_rate_ctl_reset(struct ath_softc * sc,struct ieee80211_node * ni)1042 ath_rate_ctl_reset(struct ath_softc *sc, struct ieee80211_node *ni)
1043 {
1044 #define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL)
1045 #define DOT11RATE(_ix) (rt->info[(_ix)].dot11Rate & IEEE80211_RATE_VAL)
1046 #define MCS(_ix) (ni->ni_htrates.rs_rates[_ix] | IEEE80211_RATE_MCS)
1047 struct ath_node *an = ATH_NODE(ni);
1048 struct sample_node *sn = ATH_NODE_SAMPLE(an);
1049 const HAL_RATE_TABLE *rt = sc->sc_currates;
1050 int x, y, rix;
1051
1052 KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode));
1053
1054 KASSERT(sc->sc_curmode < IEEE80211_MODE_MAX+2,
1055 ("curmode %u", sc->sc_curmode));
1056
1057 sn->sched = mrr_schedules[sc->sc_curmode];
1058 KASSERT(sn->sched != NULL,
1059 ("no mrr schedule for mode %u", sc->sc_curmode));
1060
1061 sn->static_rix = -1;
1062 ath_rate_update_static_rix(sc, ni);
1063
1064 sn->currates = sc->sc_currates;
1065
1066 /*
1067 * Construct a bitmask of usable rates. This has all
1068 * negotiated rates minus those marked by the hal as
1069 * to be ignored for doing rate control.
1070 */
1071 sn->ratemask = 0;
1072 /* MCS rates */
1073 if (ni->ni_flags & IEEE80211_NODE_HT) {
1074 for (x = 0; x < ni->ni_htrates.rs_nrates; x++) {
1075 rix = sc->sc_rixmap[MCS(x)];
1076 if (rix == 0xff)
1077 continue;
1078 /* skip rates marked broken by hal */
1079 if (!rt->info[rix].valid)
1080 continue;
1081 KASSERT(rix < SAMPLE_MAXRATES,
1082 ("mcs %u has rix %d", MCS(x), rix));
1083 sn->ratemask |= (uint64_t) 1<<rix;
1084 }
1085 }
1086
1087 /* Legacy rates */
1088 for (x = 0; x < ni->ni_rates.rs_nrates; x++) {
1089 rix = sc->sc_rixmap[RATE(x)];
1090 if (rix == 0xff)
1091 continue;
1092 /* skip rates marked broken by hal */
1093 if (!rt->info[rix].valid)
1094 continue;
1095 KASSERT(rix < SAMPLE_MAXRATES,
1096 ("rate %u has rix %d", RATE(x), rix));
1097 sn->ratemask |= (uint64_t) 1<<rix;
1098 }
1099 #ifdef IEEE80211_DEBUG
1100 if (ieee80211_msg(ni->ni_vap, IEEE80211_MSG_RATECTL)) {
1101 uint64_t mask;
1102
1103 #if defined(__DragonFly__)
1104 ieee80211_note(ni->ni_vap, "[%s] %s: size 1600 rate/tt",
1105 ath_hal_ether_sprintf(ni->ni_macaddr), __func__);
1106 #else
1107 ieee80211_note(ni->ni_vap, "[%6D] %s: size 1600 rate/tt",
1108 ni->ni_macaddr, ":", __func__);
1109 #endif
1110 for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) {
1111 if ((mask & 1) == 0)
1112 continue;
1113 kprintf(" %d %s/%d", dot11rate(rt, rix), dot11rate_label(rt, rix),
1114 calc_usecs_unicast_packet(sc, 1600, rix, 0,0,
1115 (ni->ni_chw == 40)));
1116 }
1117 kprintf("\n");
1118 }
1119 #endif
1120 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) {
1121 int size = bin_to_size(y);
1122 uint64_t mask;
1123
1124 sn->packets_sent[y] = 0;
1125 sn->current_sample_rix[y] = -1;
1126 sn->last_sample_rix[y] = 0;
1127 /* XXX start with first valid rate */
1128 sn->current_rix[y] = ffs(sn->ratemask)-1;
1129
1130 /*
1131 * Initialize the statistics buckets; these are
1132 * indexed by the rate code index.
1133 */
1134 for (rix = 0, mask = sn->ratemask; mask != 0; rix++, mask >>= 1) {
1135 if ((mask & 1) == 0) /* not a valid rate */
1136 continue;
1137 sn->stats[y][rix].successive_failures = 0;
1138 sn->stats[y][rix].tries = 0;
1139 sn->stats[y][rix].total_packets = 0;
1140 sn->stats[y][rix].packets_acked = 0;
1141 sn->stats[y][rix].last_tx = 0;
1142 sn->stats[y][rix].ewma_pct = 0;
1143
1144 sn->stats[y][rix].perfect_tx_time =
1145 calc_usecs_unicast_packet(sc, size, rix, 0, 0,
1146 (ni->ni_chw == 40));
1147 sn->stats[y][rix].average_tx_time =
1148 sn->stats[y][rix].perfect_tx_time;
1149 }
1150 }
1151 #if 0
1152 /* XXX 0, num_rates-1 are wrong */
1153 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni,
1154 "%s: %d rates %d%sMbps (%dus)- %d%sMbps (%dus)", __func__,
1155 sn->num_rates,
1156 DOT11RATE(0)/2, DOT11RATE(0) % 1 ? ".5" : "",
1157 sn->stats[1][0].perfect_tx_time,
1158 DOT11RATE(sn->num_rates-1)/2, DOT11RATE(sn->num_rates-1) % 1 ? ".5" : "",
1159 sn->stats[1][sn->num_rates-1].perfect_tx_time
1160 );
1161 #endif
1162 /* set the visible bit-rate */
1163 if (sn->static_rix != -1)
1164 ni->ni_txrate = DOT11RATE(sn->static_rix);
1165 else
1166 ni->ni_txrate = RATE(0);
1167 #undef RATE
1168 #undef DOT11RATE
1169 }
1170
1171 /*
1172 * Fetch the statistics for the given node.
1173 *
1174 * The ieee80211 node must be referenced and unlocked, however the ath_node
1175 * must be locked.
1176 *
1177 * The main difference here is that we convert the rate indexes
1178 * to 802.11 rates, or the userland output won't make much sense
1179 * as it has no access to the rix table.
1180 */
1181 int
ath_rate_fetch_node_stats(struct ath_softc * sc,struct ath_node * an,struct ath_rateioctl * rs)1182 ath_rate_fetch_node_stats(struct ath_softc *sc, struct ath_node *an,
1183 struct ath_rateioctl *rs)
1184 {
1185 struct sample_node *sn = ATH_NODE_SAMPLE(an);
1186 const HAL_RATE_TABLE *rt = sc->sc_currates;
1187 struct ath_rateioctl_tlv av;
1188 struct ath_rateioctl_rt *tv;
1189 int y;
1190 int o = 0;
1191
1192 ATH_NODE_LOCK_ASSERT(an);
1193
1194 /*
1195 * Ensure there's enough space for the statistics.
1196 */
1197 if (rs->len <
1198 sizeof(struct ath_rateioctl_tlv) +
1199 sizeof(struct ath_rateioctl_rt) +
1200 sizeof(struct ath_rateioctl_tlv) +
1201 sizeof(struct sample_node)) {
1202 device_printf(sc->sc_dev, "%s: len=%d, too short\n",
1203 __func__,
1204 rs->len);
1205 return (EINVAL);
1206 }
1207
1208 /*
1209 * Take a temporary copy of the sample node state so we can
1210 * modify it before we copy it.
1211 */
1212 #if defined(__DragonFly__)
1213 tv = kmalloc(sizeof(struct ath_rateioctl_rt), M_TEMP,
1214 M_INTWAIT | M_ZERO);
1215 #else
1216 tv = malloc(sizeof(struct ath_rateioctl_rt), M_TEMP,
1217 M_NOWAIT | M_ZERO);
1218 #endif
1219 if (tv == NULL) {
1220 return (ENOMEM);
1221 }
1222
1223 /*
1224 * Populate the rate table mapping TLV.
1225 */
1226 tv->nentries = rt->rateCount;
1227 for (y = 0; y < rt->rateCount; y++) {
1228 tv->ratecode[y] = rt->info[y].dot11Rate & IEEE80211_RATE_VAL;
1229 if (rt->info[y].phy == IEEE80211_T_HT)
1230 tv->ratecode[y] |= IEEE80211_RATE_MCS;
1231 }
1232
1233 o = 0;
1234 /*
1235 * First TLV - rate code mapping
1236 */
1237 av.tlv_id = ATH_RATE_TLV_RATETABLE;
1238 av.tlv_len = sizeof(struct ath_rateioctl_rt);
1239 copyout(&av, rs->buf + o, sizeof(struct ath_rateioctl_tlv));
1240 o += sizeof(struct ath_rateioctl_tlv);
1241 copyout(tv, rs->buf + o, sizeof(struct ath_rateioctl_rt));
1242 o += sizeof(struct ath_rateioctl_rt);
1243
1244 /*
1245 * Second TLV - sample node statistics
1246 */
1247 av.tlv_id = ATH_RATE_TLV_SAMPLENODE;
1248 av.tlv_len = sizeof(struct sample_node);
1249 copyout(&av, rs->buf + o, sizeof(struct ath_rateioctl_tlv));
1250 o += sizeof(struct ath_rateioctl_tlv);
1251
1252 /*
1253 * Copy the statistics over to the provided buffer.
1254 */
1255 copyout(sn, rs->buf + o, sizeof(struct sample_node));
1256 o += sizeof(struct sample_node);
1257
1258 kfree(tv, M_TEMP);
1259
1260 return (0);
1261 }
1262
1263 static void
sample_stats(void * arg,struct ieee80211_node * ni)1264 sample_stats(void *arg, struct ieee80211_node *ni)
1265 {
1266 struct ath_softc *sc = arg;
1267 const HAL_RATE_TABLE *rt = sc->sc_currates;
1268 struct sample_node *sn = ATH_NODE_SAMPLE(ATH_NODE(ni));
1269 uint64_t mask;
1270 int rix, y;
1271
1272 kprintf("\n[%s] refcnt %d static_rix (%d %s) ratemask 0x%jx\n",
1273 ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni),
1274 dot11rate(rt, sn->static_rix),
1275 dot11rate_label(rt, sn->static_rix),
1276 (uintmax_t)sn->ratemask);
1277 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) {
1278 kprintf("[%4u] cur rix %d (%d %s) since switch: packets %d ticks %u\n",
1279 bin_to_size(y), sn->current_rix[y],
1280 dot11rate(rt, sn->current_rix[y]),
1281 dot11rate_label(rt, sn->current_rix[y]),
1282 sn->packets_since_switch[y], sn->ticks_since_switch[y]);
1283 kprintf("[%4u] last sample (%d %s) cur sample (%d %s) packets sent %d\n",
1284 bin_to_size(y),
1285 dot11rate(rt, sn->last_sample_rix[y]),
1286 dot11rate_label(rt, sn->last_sample_rix[y]),
1287 dot11rate(rt, sn->current_sample_rix[y]),
1288 dot11rate_label(rt, sn->current_sample_rix[y]),
1289 sn->packets_sent[y]);
1290 kprintf("[%4u] packets since sample %d sample tt %u\n",
1291 bin_to_size(y), sn->packets_since_sample[y],
1292 sn->sample_tt[y]);
1293 }
1294 for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) {
1295 if ((mask & 1) == 0)
1296 continue;
1297 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) {
1298 if (sn->stats[y][rix].total_packets == 0)
1299 continue;
1300 kprintf("[%2u %s:%4u] %8ju:%-8ju (%3d%%) (EWMA %3d.%1d%%) T %8ju F %4d avg %5u last %u\n",
1301 dot11rate(rt, rix), dot11rate_label(rt, rix),
1302 bin_to_size(y),
1303 (uintmax_t) sn->stats[y][rix].total_packets,
1304 (uintmax_t) sn->stats[y][rix].packets_acked,
1305 (int) ((sn->stats[y][rix].packets_acked * 100ULL) /
1306 sn->stats[y][rix].total_packets),
1307 sn->stats[y][rix].ewma_pct / 10,
1308 sn->stats[y][rix].ewma_pct % 10,
1309 (uintmax_t) sn->stats[y][rix].tries,
1310 sn->stats[y][rix].successive_failures,
1311 sn->stats[y][rix].average_tx_time,
1312 ticks - sn->stats[y][rix].last_tx);
1313 }
1314 }
1315 }
1316
1317 static int
ath_rate_sysctl_stats(SYSCTL_HANDLER_ARGS)1318 ath_rate_sysctl_stats(SYSCTL_HANDLER_ARGS)
1319 {
1320 struct ath_softc *sc = arg1;
1321 struct ieee80211com *ic = &sc->sc_ic;
1322 int error, v;
1323
1324 v = 0;
1325 error = sysctl_handle_int(oidp, &v, 0, req);
1326 if (error || !req->newptr)
1327 return error;
1328 ieee80211_iterate_nodes(&ic->ic_sta, sample_stats, sc);
1329 return 0;
1330 }
1331
1332 static int
ath_rate_sysctl_smoothing_rate(SYSCTL_HANDLER_ARGS)1333 ath_rate_sysctl_smoothing_rate(SYSCTL_HANDLER_ARGS)
1334 {
1335 struct sample_softc *ssc = arg1;
1336 int rate, error;
1337
1338 rate = ssc->smoothing_rate;
1339 error = sysctl_handle_int(oidp, &rate, 0, req);
1340 if (error || !req->newptr)
1341 return error;
1342 if (!(0 <= rate && rate < 100))
1343 return EINVAL;
1344 ssc->smoothing_rate = rate;
1345 ssc->smoothing_minpackets = 100 / (100 - rate);
1346 return 0;
1347 }
1348
1349 static int
ath_rate_sysctl_sample_rate(SYSCTL_HANDLER_ARGS)1350 ath_rate_sysctl_sample_rate(SYSCTL_HANDLER_ARGS)
1351 {
1352 struct sample_softc *ssc = arg1;
1353 int rate, error;
1354
1355 rate = ssc->sample_rate;
1356 error = sysctl_handle_int(oidp, &rate, 0, req);
1357 if (error || !req->newptr)
1358 return error;
1359 if (!(2 <= rate && rate <= 100))
1360 return EINVAL;
1361 ssc->sample_rate = rate;
1362 return 0;
1363 }
1364
1365 static void
ath_rate_sysctlattach(struct ath_softc * sc,struct sample_softc * ssc)1366 ath_rate_sysctlattach(struct ath_softc *sc, struct sample_softc *ssc)
1367 {
1368 struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev);
1369 struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev);
1370
1371 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
1372 "smoothing_rate", CTLTYPE_INT | CTLFLAG_RW, ssc, 0,
1373 ath_rate_sysctl_smoothing_rate, "I",
1374 "sample: smoothing rate for avg tx time (%%)");
1375 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
1376 "sample_rate", CTLTYPE_INT | CTLFLAG_RW, ssc, 0,
1377 ath_rate_sysctl_sample_rate, "I",
1378 "sample: percent air time devoted to sampling new rates (%%)");
1379 /* XXX max_successive_failures, stale_failure_timeout, min_switch */
1380 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
1381 "sample_stats", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
1382 ath_rate_sysctl_stats, "I", "sample: print statistics");
1383 }
1384
1385 struct ath_ratectrl *
ath_rate_attach(struct ath_softc * sc)1386 ath_rate_attach(struct ath_softc *sc)
1387 {
1388 struct sample_softc *ssc;
1389
1390 #if defined(__DragonFly__)
1391 ssc = kmalloc(sizeof(struct sample_softc), M_DEVBUF, M_INTWAIT|M_ZERO);
1392 #else
1393 ssc = malloc(sizeof(struct sample_softc), M_DEVBUF, M_NOWAIT|M_ZERO);
1394 #endif
1395 if (ssc == NULL)
1396 return NULL;
1397 ssc->arc.arc_space = sizeof(struct sample_node);
1398 ssc->smoothing_rate = 75; /* ewma percentage ([0..99]) */
1399 ssc->smoothing_minpackets = 100 / (100 - ssc->smoothing_rate);
1400 ssc->sample_rate = 10; /* %time to try diff tx rates */
1401 ssc->max_successive_failures = 3; /* threshold for rate sampling*/
1402 ssc->stale_failure_timeout = 10 * hz; /* 10 seconds */
1403 ssc->min_switch = hz; /* 1 second */
1404 ath_rate_sysctlattach(sc, ssc);
1405 return &ssc->arc;
1406 }
1407
1408 void
ath_rate_detach(struct ath_ratectrl * arc)1409 ath_rate_detach(struct ath_ratectrl *arc)
1410 {
1411 struct sample_softc *ssc = (struct sample_softc *) arc;
1412
1413 kfree(ssc, M_DEVBUF);
1414 }
1415
1416 #if defined(__DragonFly__)
1417
1418 /*
1419 * Module glue.
1420 */
1421 static int
sample_modevent(module_t mod,int type,void * unused)1422 sample_modevent(module_t mod, int type, void *unused)
1423 {
1424 int error;
1425
1426 wlan_serialize_enter();
1427
1428 switch (type) {
1429 case MOD_LOAD:
1430 if (bootverbose) {
1431 kprintf("ath_rate: <SampleRate bit-rate "
1432 "selection algorithm>\n");
1433 }
1434 error = 0;
1435 break;
1436 case MOD_UNLOAD:
1437 error = 0;
1438 break;
1439 default:
1440 error = EINVAL;
1441 break;
1442 }
1443 wlan_serialize_exit();
1444
1445 return error;
1446 }
1447
1448 static moduledata_t sample_mod = {
1449 "ath_rate",
1450 sample_modevent,
1451 0
1452 };
1453
1454 DECLARE_MODULE(ath_rate, sample_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
1455 MODULE_VERSION(ath_rate, 1);
1456 MODULE_DEPEND(ath_rate, ath_hal, 1, 1, 1);
1457 MODULE_DEPEND(ath_rate, wlan, 1, 1, 1);
1458
1459 #endif
1460