if_ath - Properly remove sysctls on detach.
[dragonfly.git] / sys / dev / netif / ath / rate_sample / sample.c
CommitLineData
493caacd 1/*-
193b341d
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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, 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.
35 *
493caacd
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36 * $FreeBSD: head/sys/dev/ath/ath_rate/sample/sample.c 194135 2009-06-13 23:36:54Z sam $
37 * $DragonFly$
193b341d
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38 */
39
40/*
41 * John Bicket's SampleRate control algorithm.
42 */
493caacd
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43#include "opt_inet.h"
44#include "opt_wlan.h"
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45
46#include <sys/param.h>
47#include <sys/systm.h>
48#include <sys/sysctl.h>
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49#include <sys/kernel.h>
50#include <sys/lock.h>
493caacd 51#include <sys/mutex.h>
193b341d 52#include <sys/errno.h>
493caacd 53
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54#include <sys/bus.h>
55
56#include <sys/socket.h>
57
58#include <net/if.h>
59#include <net/if_media.h>
60#include <net/if_arp.h>
61
62#include <netproto/802_11/ieee80211_var.h>
63
64#include <net/bpf.h>
65
493caacd
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66#ifdef INET
67#include <netinet/in.h>
68#include <netinet/if_ether.h>
69#endif
70
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71#include <dev/netif/ath/ath/if_athvar.h>
72#include <dev/netif/ath/rate_sample/sample.h>
3f720b20 73#include <dev/netif/ath/hal/ath_hal/ah_desc.h>
193b341d 74
193b341d
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75/*
76 * This file is an implementation of the SampleRate algorithm
77 * in "Bit-rate Selection in Wireless Networks"
78 * (http://www.pdos.lcs.mit.edu/papers/jbicket-ms.ps)
79 *
80 * SampleRate chooses the bit-rate it predicts will provide the most
81 * throughput based on estimates of the expected per-packet
82 * transmission time for each bit-rate. SampleRate periodically sends
83 * packets at bit-rates other than the current one to estimate when
84 * another bit-rate will provide better performance. SampleRate
85 * switches to another bit-rate when its estimated per-packet
86 * transmission time becomes smaller than the current bit-rate's.
87 * SampleRate reduces the number of bit-rates it must sample by
88 * eliminating those that could not perform better than the one
89 * currently being used. SampleRate also stops probing at a bit-rate
90 * if it experiences several successive losses.
91 *
92 * The difference between the algorithm in the thesis and the one in this
93 * file is that the one in this file uses a ewma instead of a window.
94 *
95 * Also, this implementation tracks the average transmission time for
96 * a few different packet sizes independently for each link.
97 */
98
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99static void ath_rate_ctl_reset(struct ath_softc *, struct ieee80211_node *);
100
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101static const int packet_size_bins[NUM_PACKET_SIZE_BINS] = { 250, 1600 };
102
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103static __inline int
104size_to_bin(int size)
105{
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106#if NUM_PACKET_SIZE_BINS > 1
107 if (size <= packet_size_bins[0])
108 return 0;
109#endif
110#if NUM_PACKET_SIZE_BINS > 2
111 if (size <= packet_size_bins[1])
112 return 1;
113#endif
114#if NUM_PACKET_SIZE_BINS > 3
115 if (size <= packet_size_bins[2])
116 return 2;
117#endif
118#if NUM_PACKET_SIZE_BINS > 4
119#error "add support for more packet sizes"
120#endif
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121 return NUM_PACKET_SIZE_BINS-1;
122}
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123
124static __inline int
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125bin_to_size(int index)
126{
127 return packet_size_bins[index];
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128}
129
130void
131ath_rate_node_init(struct ath_softc *sc, struct ath_node *an)
132{
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133 /* NB: assumed to be zero'd by caller */
134}
135
136void
137ath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an)
138{
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139}
140
193b341d 141/*
493caacd 142 * Return the rix with the lowest average_tx_time,
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143 * or -1 if all the average_tx_times are 0.
144 */
7b9f668c 145static __inline int
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146pick_best_rate(struct sample_node *sn, const HAL_RATE_TABLE *rt,
147 int size_bin, int require_acked_before)
193b341d 148{
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149 int best_rate_rix, best_rate_tt;
150 uint32_t mask;
151 int rix, tt;
152
153 best_rate_rix = 0;
154 best_rate_tt = 0;
155 for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) {
156 if ((mask & 1) == 0) /* not a supported rate */
193b341d 157 continue;
193b341d 158
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159 tt = sn->stats[size_bin][rix].average_tx_time;
160 if (tt <= 0 ||
161 (require_acked_before &&
162 !sn->stats[size_bin][rix].packets_acked))
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163 continue;
164
165 /* don't use a bit-rate that has been failing */
493caacd 166 if (sn->stats[size_bin][rix].successive_failures > 3)
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167 continue;
168
493caacd 169 if (best_rate_tt == 0 || tt < best_rate_tt) {
193b341d 170 best_rate_tt = tt;
493caacd 171 best_rate_rix = rix;
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172 }
173 }
493caacd 174 return (best_rate_tt ? best_rate_rix : -1);
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175}
176
177/*
493caacd 178 * Pick a good "random" bit-rate to sample other than the current one.
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179 */
180static __inline int
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181pick_sample_rate(struct sample_softc *ssc , struct sample_node *sn,
182 const HAL_RATE_TABLE *rt, int size_bin)
193b341d 183{
493caacd
RP
184#define DOT11RATE(ix) (rt->info[ix].dot11Rate & IEEE80211_RATE_VAL)
185 int current_rix, rix;
186 unsigned current_tt;
187 uint32_t mask;
193b341d 188
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RP
189 current_rix = sn->current_rix[size_bin];
190 if (current_rix < 0) {
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191 /* no successes yet, send at the lowest bit-rate */
192 return 0;
193 }
193b341d 194
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RP
195 current_tt = sn->stats[size_bin][current_rix].average_tx_time;
196
197 rix = sn->last_sample_rix[size_bin]+1; /* next sample rate */
198 mask = sn->ratemask &~ (1<<current_rix);/* don't sample current rate */
199 while (mask != 0) {
200 if ((mask & (1<<rix)) == 0) { /* not a supported rate */
201 nextrate:
202 if (++rix >= rt->rateCount)
203 rix = 0;
193b341d 204 continue;
493caacd 205 }
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206
207 /* this bit-rate is always worse than the current one */
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208 if (sn->stats[size_bin][rix].perfect_tx_time > current_tt) {
209 mask &= ~(1<<rix);
210 goto nextrate;
211 }
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212
213 /* rarely sample bit-rates that fail a lot */
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RP
214 if (sn->stats[size_bin][rix].successive_failures > ssc->max_successive_failures &&
215 ticks - sn->stats[size_bin][rix].last_tx < ssc->stale_failure_timeout) {
216 mask &= ~(1<<rix);
217 goto nextrate;
218 }
193b341d 219
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RP
220 /* don't sample more than 2 rates higher for rates > 11M */
221 if (DOT11RATE(rix) > 2*11 && rix > current_rix + 2) {
222 mask &= ~(1<<rix);
223 goto nextrate;
224 }
193b341d 225
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226 sn->last_sample_rix[size_bin] = rix;
227 return rix;
193b341d 228 }
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229 return current_rix;
230#undef DOT11RATE
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231}
232
233void
234ath_rate_findrate(struct ath_softc *sc, struct ath_node *an,
235 int shortPreamble, size_t frameLen,
493caacd 236 u_int8_t *rix0, int *try0, u_int8_t *txrate)
193b341d 237{
493caacd
RP
238#define DOT11RATE(ix) (rt->info[ix].dot11Rate & IEEE80211_RATE_VAL)
239#define RATE(ix) (DOT11RATE(ix) / 2)
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240 struct sample_node *sn = ATH_NODE_SAMPLE(an);
241 struct sample_softc *ssc = ATH_SOFTC_SAMPLE(sc);
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242 struct ifnet *ifp = sc->sc_ifp;
243 struct ieee80211com *ic = ifp->if_l2com;
244 const HAL_RATE_TABLE *rt = sc->sc_currates;
245 const int size_bin = size_to_bin(frameLen);
246 int rix, mrr, best_rix, change_rates;
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247 unsigned average_tx_time;
248
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249 if (sn->static_rix != -1) {
250 rix = sn->static_rix;
251 *try0 = ATH_TXMAXTRY;
252 goto done;
253 }
254
193b341d 255 mrr = sc->sc_mrretry && !(ic->ic_flags & IEEE80211_F_USEPROT);
193b341d 256
493caacd
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257 best_rix = pick_best_rate(sn, rt, size_bin, !mrr);
258 if (best_rix >= 0) {
259 average_tx_time = sn->stats[size_bin][best_rix].average_tx_time;
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260 } else {
261 average_tx_time = 0;
262 }
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263 /*
264 * Limit the time measuring the performance of other tx
265 * rates to sample_rate% of the total transmission time.
266 */
267 if (sn->sample_tt[size_bin] < average_tx_time * (sn->packets_since_sample[size_bin]*ssc->sample_rate/100)) {
268 rix = pick_sample_rate(ssc, sn, rt, size_bin);
269 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL,
270 &an->an_node, "size %u sample rate %d current rate %d",
271 bin_to_size(size_bin), RATE(rix),
272 RATE(sn->current_rix[size_bin]));
273 if (rix != sn->current_rix[size_bin]) {
274 sn->current_sample_rix[size_bin] = rix;
193b341d 275 } else {
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RP
276 sn->current_sample_rix[size_bin] = -1;
277 }
278 sn->packets_since_sample[size_bin] = 0;
279 } else {
280 change_rates = 0;
281 if (!sn->packets_sent[size_bin] || best_rix == -1) {
282 /* no packet has been sent successfully yet */
283 for (rix = rt->rateCount-1; rix > 0; rix--) {
284 if ((sn->ratemask & (1<<rix)) == 0)
285 continue;
286 /*
287 * Pick the highest rate <= 36 Mbps
288 * that hasn't failed.
289 */
290 if (DOT11RATE(rix) <= 72 &&
291 sn->stats[size_bin][rix].successive_failures == 0) {
292 break;
193b341d 293 }
193b341d 294 }
493caacd
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295 change_rates = 1;
296 best_rix = rix;
297 } else if (sn->packets_sent[size_bin] < 20) {
298 /* let the bit-rate switch quickly during the first few packets */
299 change_rates = 1;
300 } else if (ticks - ssc->min_switch > sn->ticks_since_switch[size_bin]) {
301 /* min_switch seconds have gone by */
302 change_rates = 1;
303 } else if (2*average_tx_time < sn->stats[size_bin][sn->current_rix[size_bin]].average_tx_time) {
304 /* the current bit-rate is twice as slow as the best one */
305 change_rates = 1;
306 }
193b341d 307
493caacd
RP
308 sn->packets_since_sample[size_bin]++;
309
310 if (change_rates) {
311 if (best_rix != sn->current_rix[size_bin]) {
312 IEEE80211_NOTE(an->an_node.ni_vap,
313 IEEE80211_MSG_RATECTL,
314 &an->an_node,
315"%s: size %d switch rate %d (%d/%d) -> %d (%d/%d) after %d packets mrr %d",
316 __func__,
317 bin_to_size(size_bin),
318 RATE(sn->current_rix[size_bin]),
319 sn->stats[size_bin][sn->current_rix[size_bin]].average_tx_time,
320 sn->stats[size_bin][sn->current_rix[size_bin]].perfect_tx_time,
321 RATE(best_rix),
322 sn->stats[size_bin][best_rix].average_tx_time,
323 sn->stats[size_bin][best_rix].perfect_tx_time,
324 sn->packets_since_switch[size_bin],
325 mrr);
193b341d 326 }
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RP
327 sn->packets_since_switch[size_bin] = 0;
328 sn->current_rix[size_bin] = best_rix;
329 sn->ticks_since_switch[size_bin] = ticks;
330 /*
331 * Set the visible txrate for this node.
332 */
333 an->an_node.ni_txrate = DOT11RATE(best_rix);
193b341d 334 }
493caacd
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335 rix = sn->current_rix[size_bin];
336 sn->packets_since_switch[size_bin]++;
193b341d 337 }
493caacd
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338 *try0 = mrr ? sn->sched[rix].t0 : ATH_TXMAXTRY;
339done:
340 KASSERT(rix >= 0 && rix < rt->rateCount, ("rix is %d", rix));
193b341d 341
493caacd
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342 *rix0 = rix;
343 *txrate = rt->info[rix].rateCode
344 | (shortPreamble ? rt->info[rix].shortPreamble : 0);
193b341d 345 sn->packets_sent[size_bin]++;
493caacd
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346#undef DOT11RATE
347#undef RATE
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348}
349
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350#define A(_r) \
351 (((_r) == 6) ? 0 : (((_r) == 9) ? 1 : (((_r) == 12) ? 2 : \
352 (((_r) == 18) ? 3 : (((_r) == 24) ? 4 : (((_r) == 36) ? 5 : \
353 (((_r) == 48) ? 6 : (((_r) == 54) ? 7 : 0))))))))
354static const struct txschedule series_11a[] = {
355 { 3,A( 6), 3,A( 6), 0,A( 6), 0,A( 6) }, /* 6Mb/s */
356 { 4,A( 9), 3,A( 6), 4,A( 6), 0,A( 6) }, /* 9Mb/s */
357 { 4,A(12), 3,A( 6), 4,A( 6), 0,A( 6) }, /* 12Mb/s */
358 { 4,A(18), 3,A( 12), 4,A( 6), 2,A( 6) }, /* 18Mb/s */
359 { 4,A(24), 3,A( 18), 4,A( 12), 2,A( 6) }, /* 24Mb/s */
360 { 4,A(36), 3,A( 24), 4,A( 18), 2,A( 6) }, /* 36Mb/s */
361 { 4,A(48), 3,A( 36), 4,A( 24), 2,A(12) }, /* 48Mb/s */
362 { 4,A(54), 3,A( 48), 4,A( 36), 2,A(24) } /* 54Mb/s */
363};
364#undef A
365
366#define G(_r) \
367 (((_r) == 1) ? 0 : (((_r) == 2) ? 1 : (((_r) == 5.5) ? 2 : \
368 (((_r) == 11) ? 3 : (((_r) == 6) ? 4 : (((_r) == 9) ? 5 : \
369 (((_r) == 12) ? 6 : (((_r) == 18) ? 7 : (((_r) == 24) ? 8 : \
370 (((_r) == 36) ? 9 : (((_r) == 48) ? 10 : (((_r) == 54) ? 11 : 0))))))))))))
371static const struct txschedule series_11g[] = {
372 { 3,G( 1), 3,G( 1), 0,G( 1), 0,G( 1) }, /* 1Mb/s */
373 { 4,G( 2), 3,G( 1), 4,G( 1), 0,G( 1) }, /* 2Mb/s */
374 { 4,G(5.5),3,G( 2), 4,G( 1), 2,G( 1) }, /* 5.5Mb/s */
375 { 4,G(11), 3,G(5.5), 4,G( 2), 2,G( 1) }, /* 11Mb/s */
376 { 4,G( 6), 3,G(5.5), 4,G( 2), 2,G( 1) }, /* 6Mb/s */
377 { 4,G( 9), 3,G( 6), 4,G(5.5), 2,G( 1) }, /* 9Mb/s */
378 { 4,G(12), 3,G( 11), 4,G(5.5), 2,G( 1) }, /* 12Mb/s */
379 { 4,G(18), 3,G( 12), 4,G( 11), 2,G( 1) }, /* 18Mb/s */
380 { 4,G(24), 3,G( 18), 4,G( 12), 2,G( 1) }, /* 24Mb/s */
381 { 4,G(36), 3,G( 24), 4,G( 18), 2,G( 1) }, /* 36Mb/s */
382 { 4,G(48), 3,G( 36), 4,G( 24), 2,G( 1) }, /* 48Mb/s */
383 { 4,G(54), 3,G( 48), 4,G( 36), 2,G( 1) } /* 54Mb/s */
384};
385#undef G
386
387#define H(_r) \
388 (((_r) == 3) ? 0 : (((_r) == 4.5) ? 1 : (((_r) == 6) ? 2 : \
389 (((_r) == 9) ? 3 : (((_r) == 12) ? 4 : (((_r) == 18) ? 5 : \
390 (((_r) == 24) ? 6 : (((_r) == 27) ? 7 : 0))))))))
391static const struct txschedule series_half[] = {
392 { 3,H( 3), 3,H( 3), 0,H( 3), 0,H( 3) }, /* 3Mb/s */
393 { 4,H(4.5),3,H( 3), 4,H( 3), 0,H( 3) }, /* 4.5Mb/s */
394 { 4,H( 6), 3,H( 3), 4,H( 3), 0,H( 3) }, /* 6Mb/s */
395 { 4,H( 9), 3,H( 6), 4,H( 3), 2,H( 3) }, /* 9Mb/s */
396 { 4,H(12), 3,H( 9), 4,H( 6), 2,H( 3) }, /* 12Mb/s */
397 { 4,H(18), 3,H( 12), 4,H( 9), 2,H( 3) }, /* 18Mb/s */
398 { 4,H(24), 3,H( 18), 4,H( 12), 2,H( 6) }, /* 24Mb/s */
399 { 4,H(27), 3,H( 24), 4,H( 18), 2,H(12) } /* 27Mb/s */
400};
401#undef H
402
403#ifdef Q
404#undef Q /* sun4v bogosity */
405#endif
406#define Q(_r) \
407 (((_r) == 1.5) ? 0 : (((_r) ==2.25) ? 1 : (((_r) == 3) ? 2 : \
408 (((_r) == 4.5) ? 3 : (((_r) == 6) ? 4 : (((_r) == 9) ? 5 : \
409 (((_r) == 12) ? 6 : (((_r) == 13.5)? 7 : 0))))))))
410static const struct txschedule series_quarter[] = {
411 { 3,Q( 1.5),3,Q(1.5), 0,Q(1.5), 0,Q(1.5) }, /* 1.5Mb/s */
412 { 4,Q(2.25),3,Q(1.5), 4,Q(1.5), 0,Q(1.5) }, /*2.25Mb/s */
413 { 4,Q( 3),3,Q(1.5), 4,Q(1.5), 0,Q(1.5) }, /* 3Mb/s */
414 { 4,Q( 4.5),3,Q( 3), 4,Q(1.5), 2,Q(1.5) }, /* 4.5Mb/s */
415 { 4,Q( 6),3,Q(4.5), 4,Q( 3), 2,Q(1.5) }, /* 6Mb/s */
416 { 4,Q( 9),3,Q( 6), 4,Q(4.5), 2,Q(1.5) }, /* 9Mb/s */
417 { 4,Q( 12),3,Q( 9), 4,Q( 6), 2,Q( 3) }, /* 12Mb/s */
418 { 4,Q(13.5),3,Q( 12), 4,Q( 9), 2,Q( 6) } /*13.5Mb/s */
419};
420#undef Q
421
193b341d
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422void
423ath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an,
424 struct ath_desc *ds, int shortPreamble, u_int8_t rix)
425{
426 struct sample_node *sn = ATH_NODE_SAMPLE(an);
493caacd
RP
427 const struct txschedule *sched = &sn->sched[rix];
428 const HAL_RATE_TABLE *rt = sc->sc_currates;
429 uint8_t rix1, s1code, rix2, s2code, rix3, s3code;
430
431 /* XXX precalculate short preamble tables */
432 rix1 = sched->r1;
433 s1code = rt->info[rix1].rateCode
434 | (shortPreamble ? rt->info[rix1].shortPreamble : 0);
435 rix2 = sched->r2;
436 s2code = rt->info[rix2].rateCode
437 | (shortPreamble ? rt->info[rix2].shortPreamble : 0);
438 rix3 = sched->r3;
439 s3code = rt->info[rix3].rateCode
440 | (shortPreamble ? rt->info[rix3].shortPreamble : 0);
441 ath_hal_setupxtxdesc(sc->sc_ah, ds,
442 s1code, sched->t1, /* series 1 */
443 s2code, sched->t2, /* series 2 */
444 s3code, sched->t3); /* series 3 */
193b341d
SZ
445}
446
447static void
448update_stats(struct ath_softc *sc, struct ath_node *an,
449 int frame_size,
493caacd
RP
450 int rix0, int tries0,
451 int rix1, int tries1,
452 int rix2, int tries2,
453 int rix3, int tries3,
193b341d
SZ
454 int short_tries, int tries, int status)
455{
456 struct sample_node *sn = ATH_NODE_SAMPLE(an);
457 struct sample_softc *ssc = ATH_SOFTC_SAMPLE(sc);
493caacd
RP
458 const int size_bin = size_to_bin(frame_size);
459 const int size = bin_to_size(size_bin);
460 int tt, tries_so_far;
461
462 if (!IS_RATE_DEFINED(sn, rix0))
8982d733 463 return;
493caacd
RP
464 tt = calc_usecs_unicast_packet(sc, size, rix0, short_tries,
465 MIN(tries0, tries) - 1);
466 tries_so_far = tries0;
467
468 if (tries1 && tries_so_far < tries) {
469 if (!IS_RATE_DEFINED(sn, rix1))
8982d733 470 return;
493caacd
RP
471 tt += calc_usecs_unicast_packet(sc, size, rix1, short_tries,
472 MIN(tries1 + tries_so_far, tries) - tries_so_far - 1);
473 tries_so_far += tries1;
193b341d 474 }
193b341d 475
493caacd
RP
476 if (tries2 && tries_so_far < tries) {
477 if (!IS_RATE_DEFINED(sn, rix2))
8982d733 478 return;
493caacd
RP
479 tt += calc_usecs_unicast_packet(sc, size, rix2, short_tries,
480 MIN(tries2 + tries_so_far, tries) - tries_so_far - 1);
481 tries_so_far += tries2;
193b341d
SZ
482 }
483
493caacd
RP
484 if (tries3 && tries_so_far < tries) {
485 if (!IS_RATE_DEFINED(sn, rix3))
8982d733 486 return;
493caacd
RP
487 tt += calc_usecs_unicast_packet(sc, size, rix3, short_tries,
488 MIN(tries3 + tries_so_far, tries) - tries_so_far - 1);
193b341d 489 }
493caacd
RP
490
491 if (sn->stats[size_bin][rix0].total_packets < ssc->smoothing_minpackets) {
193b341d 492 /* just average the first few packets */
493caacd
RP
493 int avg_tx = sn->stats[size_bin][rix0].average_tx_time;
494 int packets = sn->stats[size_bin][rix0].total_packets;
495 sn->stats[size_bin][rix0].average_tx_time = (tt+(avg_tx*packets))/(packets+1);
193b341d
SZ
496 } else {
497 /* use a ewma */
493caacd
RP
498 sn->stats[size_bin][rix0].average_tx_time =
499 ((sn->stats[size_bin][rix0].average_tx_time * ssc->smoothing_rate) +
500 (tt * (100 - ssc->smoothing_rate))) / 100;
193b341d
SZ
501 }
502
493caacd 503 if (status != 0) {
193b341d 504 int y;
493caacd 505 sn->stats[size_bin][rix0].successive_failures++;
193b341d 506 for (y = size_bin+1; y < NUM_PACKET_SIZE_BINS; y++) {
493caacd
RP
507 /*
508 * Also say larger packets failed since we
509 * assume if a small packet fails at a
193b341d
SZ
510 * bit-rate then a larger one will also.
511 */
493caacd
RP
512 sn->stats[y][rix0].successive_failures++;
513 sn->stats[y][rix0].last_tx = ticks;
514 sn->stats[y][rix0].tries += tries;
515 sn->stats[y][rix0].total_packets++;
193b341d
SZ
516 }
517 } else {
493caacd
RP
518 sn->stats[size_bin][rix0].packets_acked++;
519 sn->stats[size_bin][rix0].successive_failures = 0;
193b341d 520 }
493caacd
RP
521 sn->stats[size_bin][rix0].tries += tries;
522 sn->stats[size_bin][rix0].last_tx = ticks;
523 sn->stats[size_bin][rix0].total_packets++;
524
525 if (rix0 == sn->current_sample_rix[size_bin]) {
526 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL,
527 &an->an_node,
528"%s: size %d %s sample rate %d tries (%d/%d) tt %d avg_tt (%d/%d)",
529 __func__,
530 size,
531 status ? "FAIL" : "OK",
532 rix0, short_tries, tries, tt,
533 sn->stats[size_bin][rix0].average_tx_time,
534 sn->stats[size_bin][rix0].perfect_tx_time);
193b341d 535 sn->sample_tt[size_bin] = tt;
493caacd 536 sn->current_sample_rix[size_bin] = -1;
193b341d
SZ
537 }
538}
539
493caacd
RP
540static void
541badrate(struct ifnet *ifp, int series, int hwrate, int tries, int status)
542{
543 if_printf(ifp, "bad series%d hwrate 0x%x, tries %u ts_status 0x%x\n",
544 series, hwrate, tries, status);
545}
546
193b341d
SZ
547void
548ath_rate_tx_complete(struct ath_softc *sc, struct ath_node *an,
8982d733 549 const struct ath_buf *bf)
193b341d 550{
493caacd
RP
551 struct ifnet *ifp = sc->sc_ifp;
552 struct ieee80211com *ic = ifp->if_l2com;
193b341d 553 struct sample_node *sn = ATH_NODE_SAMPLE(an);
8982d733
SZ
554 const struct ath_tx_status *ts = &bf->bf_status.ds_txstat;
555 const struct ath_desc *ds0 = &bf->bf_desc[0];
493caacd
RP
556 int final_rix, short_tries, long_tries, frame_size;
557 const HAL_RATE_TABLE *rt = sc->sc_currates;
193b341d
SZ
558 int mrr;
559
493caacd 560 final_rix = rt->rateCodeToIndex[ts->ts_rate];
8982d733
SZ
561 short_tries = ts->ts_shortretry;
562 long_tries = ts->ts_longretry + 1;
193b341d
SZ
563 frame_size = ds0->ds_ctl0 & 0x0fff; /* low-order 12 bits of ds_ctl0 */
564 if (frame_size == 0) /* NB: should not happen */
565 frame_size = 1500;
566
493caacd
RP
567 if (sn->ratemask == 0) {
568 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL,
569 &an->an_node,
570 "%s: size %d %s rate/try %d/%d no rates yet",
571 __func__,
572 bin_to_size(size_to_bin(frame_size)),
573 ts->ts_status ? "FAIL" : "OK",
574 short_tries, long_tries);
193b341d
SZ
575 return;
576 }
193b341d 577 mrr = sc->sc_mrretry && !(ic->ic_flags & IEEE80211_F_USEPROT);
493caacd
RP
578 if (!mrr || ts->ts_finaltsi == 0) {
579 if (!IS_RATE_DEFINED(sn, final_rix)) {
580 badrate(ifp, 0, ts->ts_rate, long_tries, ts->ts_status);
581 return;
582 }
8982d733
SZ
583 /*
584 * Only one rate was used; optimize work.
585 */
493caacd
RP
586 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL,
587 &an->an_node, "%s: size %d %s rate/try %d/%d/%d",
588 __func__,
589 bin_to_size(size_to_bin(frame_size)),
590 ts->ts_status ? "FAIL" : "OK",
591 final_rix, short_tries, long_tries);
8982d733 592 update_stats(sc, an, frame_size,
493caacd 593 final_rix, long_tries,
8982d733
SZ
594 0, 0,
595 0, 0,
596 0, 0,
597 short_tries, long_tries, ts->ts_status);
193b341d 598 } else {
493caacd
RP
599 int hwrate0, rix0, tries0;
600 int hwrate1, rix1, tries1;
601 int hwrate2, rix2, tries2;
602 int hwrate3, rix3, tries3;
8982d733 603 int finalTSIdx = ts->ts_finaltsi;
193b341d
SZ
604
605 /*
606 * Process intermediate rates that failed.
607 */
8982d733
SZ
608 if (sc->sc_ah->ah_magic != 0x20065416) {
609 hwrate0 = MS(ds0->ds_ctl3, AR_XmitRate0);
610 hwrate1 = MS(ds0->ds_ctl3, AR_XmitRate1);
611 hwrate2 = MS(ds0->ds_ctl3, AR_XmitRate2);
612 hwrate3 = MS(ds0->ds_ctl3, AR_XmitRate3);
613 } else {
614 hwrate0 = MS(ds0->ds_ctl3, AR5416_XmitRate0);
615 hwrate1 = MS(ds0->ds_ctl3, AR5416_XmitRate1);
616 hwrate2 = MS(ds0->ds_ctl3, AR5416_XmitRate2);
617 hwrate3 = MS(ds0->ds_ctl3, AR5416_XmitRate3);
618 }
193b341d 619
493caacd 620 rix0 = rt->rateCodeToIndex[hwrate0];
8982d733 621 tries0 = MS(ds0->ds_ctl2, AR_XmitDataTries0);
8982d733 622
493caacd 623 rix1 = rt->rateCodeToIndex[hwrate1];
8982d733 624 tries1 = MS(ds0->ds_ctl2, AR_XmitDataTries1);
8982d733 625
493caacd 626 rix2 = rt->rateCodeToIndex[hwrate2];
8982d733 627 tries2 = MS(ds0->ds_ctl2, AR_XmitDataTries2);
8982d733 628
493caacd 629 rix3 = rt->rateCodeToIndex[hwrate3];
8982d733 630 tries3 = MS(ds0->ds_ctl2, AR_XmitDataTries3);
493caacd
RP
631
632 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL,
633 &an->an_node,
634"%s: size %d finaltsidx %d tries %d %s rate/try [%d/%d %d/%d %d/%d %d/%d]",
635 __func__,
636 bin_to_size(size_to_bin(frame_size)),
637 finalTSIdx,
638 long_tries,
639 ts->ts_status ? "FAIL" : "OK",
640 rix0, tries0,
641 rix1, tries1,
642 rix2, tries2,
643 rix3, tries3);
644
645 if (tries0 && !IS_RATE_DEFINED(sn, rix0))
646 badrate(ifp, 0, hwrate0, tries0, ts->ts_status);
647 if (tries1 && !IS_RATE_DEFINED(sn, rix1))
648 badrate(ifp, 1, hwrate1, tries1, ts->ts_status);
649 if (tries2 && !IS_RATE_DEFINED(sn, rix2))
650 badrate(ifp, 2, hwrate2, tries2, ts->ts_status);
651 if (tries3 && !IS_RATE_DEFINED(sn, rix3))
652 badrate(ifp, 3, hwrate3, tries3, ts->ts_status);
193b341d 653
8982d733
SZ
654 /*
655 * NB: series > 0 are not penalized for failure
656 * based on the try counts under the assumption
657 * that losses are often bursty and since we
658 * sample higher rates 1 try at a time doing so
659 * may unfairly penalize them.
660 */
193b341d
SZ
661 if (tries0) {
662 update_stats(sc, an, frame_size,
493caacd
RP
663 rix0, tries0,
664 rix1, tries1,
665 rix2, tries2,
666 rix3, tries3,
667 short_tries, long_tries,
193b341d 668 long_tries > tries0);
8982d733 669 long_tries -= tries0;
193b341d
SZ
670 }
671
672 if (tries1 && finalTSIdx > 0) {
673 update_stats(sc, an, frame_size,
493caacd
RP
674 rix1, tries1,
675 rix2, tries2,
676 rix3, tries3,
193b341d 677 0, 0,
8982d733
SZ
678 short_tries, long_tries,
679 ts->ts_status);
680 long_tries -= tries1;
193b341d
SZ
681 }
682
683 if (tries2 && finalTSIdx > 1) {
684 update_stats(sc, an, frame_size,
493caacd
RP
685 rix2, tries2,
686 rix3, tries3,
193b341d
SZ
687 0, 0,
688 0, 0,
8982d733
SZ
689 short_tries, long_tries,
690 ts->ts_status);
691 long_tries -= tries2;
193b341d
SZ
692 }
693
694 if (tries3 && finalTSIdx > 2) {
695 update_stats(sc, an, frame_size,
493caacd 696 rix3, tries3,
193b341d
SZ
697 0, 0,
698 0, 0,
699 0, 0,
8982d733
SZ
700 short_tries, long_tries,
701 ts->ts_status);
193b341d
SZ
702 }
703 }
704}
705
706void
707ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew)
708{
193b341d
SZ
709 if (isnew)
710 ath_rate_ctl_reset(sc, &an->an_node);
711}
712
493caacd
RP
713static const struct txschedule *mrr_schedules[IEEE80211_MODE_MAX+2] = {
714 NULL, /* IEEE80211_MODE_AUTO */
715 series_11a, /* IEEE80211_MODE_11A */
716 series_11g, /* IEEE80211_MODE_11B */
717 series_11g, /* IEEE80211_MODE_11G */
718 NULL, /* IEEE80211_MODE_FH */
719 series_11a, /* IEEE80211_MODE_TURBO_A */
720 series_11g, /* IEEE80211_MODE_TURBO_G */
721 series_11a, /* IEEE80211_MODE_STURBO_A */
722 series_11a, /* IEEE80211_MODE_11NA */
723 series_11g, /* IEEE80211_MODE_11NG */
724 series_half, /* IEEE80211_MODE_HALF */
725 series_quarter, /* IEEE80211_MODE_QUARTER */
726};
727
193b341d
SZ
728/*
729 * Initialize the tables for a node.
730 */
731static void
732ath_rate_ctl_reset(struct ath_softc *sc, struct ieee80211_node *ni)
733{
734#define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL)
493caacd 735#define DOT11RATE(_ix) (rt->info[(_ix)].dot11Rate & IEEE80211_RATE_VAL)
193b341d 736 struct ath_node *an = ATH_NODE(ni);
493caacd 737 const struct ieee80211_txparam *tp = ni->ni_txparms;
193b341d
SZ
738 struct sample_node *sn = ATH_NODE_SAMPLE(an);
739 const HAL_RATE_TABLE *rt = sc->sc_currates;
493caacd 740 int x, y, srate, rix;
193b341d
SZ
741
742 KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode));
493caacd
RP
743
744 KASSERT(sc->sc_curmode < IEEE80211_MODE_MAX+2,
745 ("curmode %u", sc->sc_curmode));
746 sn->sched = mrr_schedules[sc->sc_curmode];
747 KASSERT(sn->sched != NULL,
748 ("no mrr schedule for mode %u", sc->sc_curmode));
749
750 sn->static_rix = -1;
751 if (tp != NULL && tp->ucastrate != IEEE80211_FIXED_RATE_NONE) {
193b341d 752 /*
493caacd
RP
753 * A fixed rate is to be used; ucastrate is the IEEE code
754 * for this rate (sans basic bit). Check this against the
755 * negotiated rate set for the node. Note the fixed rate
756 * may not be available for various reasons so we only
757 * setup the static rate index if the lookup is successful.
758 * XXX handle MCS
193b341d 759 */
493caacd
RP
760 for (srate = ni->ni_rates.rs_nrates - 1; srate >= 0; srate--)
761 if (RATE(srate) == tp->ucastrate) {
762 sn->static_rix = sc->sc_rixmap[tp->ucastrate];
763 break;
764 }
765#ifdef IEEE80211_DEBUG
766 if (sn->static_rix == -1) {
767 IEEE80211_NOTE(ni->ni_vap,
768 IEEE80211_MSG_RATECTL, ni,
769 "%s: ucastrate %u not found, nrates %u",
770 __func__, tp->ucastrate,
771 ni->ni_rates.rs_nrates);
772 }
773#endif
193b341d
SZ
774 }
775
493caacd
RP
776 /*
777 * Construct a bitmask of usable rates. This has all
778 * negotiated rates minus those marked by the hal as
779 * to be ignored for doing rate control.
780 */
781 sn->ratemask = 0;
782 for (x = 0; x < ni->ni_rates.rs_nrates; x++) {
783 rix = sc->sc_rixmap[RATE(x)];
784 if (rix == 0xff)
193b341d 785 continue;
493caacd
RP
786 /* skip rates marked broken by hal */
787 if (!rt->info[rix].valid)
788 continue;
789 KASSERT(rix < SAMPLE_MAXRATES,
790 ("rate %u has rix %d", RATE(x), rix));
791 sn->ratemask |= 1<<rix;
792 }
793#ifdef IEEE80211_DEBUG
794 if (ieee80211_msg(ni->ni_vap, IEEE80211_MSG_RATECTL)) {
795 uint32_t mask;
796
797 ieee80211_note(ni->ni_vap, "[%6D] %s: size 1600 rate/tt",
798 ni->ni_macaddr, ":", __func__);
799 for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) {
800 if ((mask & 1) == 0)
801 continue;
802 kprintf(" %d/%d", DOT11RATE(rix) / 2,
803 calc_usecs_unicast_packet(sc, 1600, rix, 0,0));
193b341d 804 }
493caacd 805 kprintf("\n");
193b341d 806 }
493caacd 807#endif
193b341d
SZ
808 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) {
809 int size = bin_to_size(y);
493caacd
RP
810 uint32_t mask;
811
193b341d 812 sn->packets_sent[y] = 0;
493caacd
RP
813 sn->current_sample_rix[y] = -1;
814 sn->last_sample_rix[y] = 0;
815 /* XXX start with first valid rate */
816 sn->current_rix[y] = ffs(sn->ratemask)-1;
193b341d 817
493caacd
RP
818 /*
819 * Initialize the statistics buckets; these are
820 * indexed by the rate code index.
821 */
822 for (rix = 0, mask = sn->ratemask; mask != 0; rix++, mask >>= 1) {
823 if ((mask & 1) == 0) /* not a valid rate */
824 continue;
825 sn->stats[y][rix].successive_failures = 0;
826 sn->stats[y][rix].tries = 0;
827 sn->stats[y][rix].total_packets = 0;
828 sn->stats[y][rix].packets_acked = 0;
829 sn->stats[y][rix].last_tx = 0;
193b341d 830
493caacd
RP
831 sn->stats[y][rix].perfect_tx_time =
832 calc_usecs_unicast_packet(sc, size, rix, 0, 0);
833 sn->stats[y][rix].average_tx_time =
834 sn->stats[y][rix].perfect_tx_time;
193b341d 835 }
193b341d 836 }
493caacd
RP
837#if 0
838 /* XXX 0, num_rates-1 are wrong */
839 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni,
840 "%s: %d rates %d%sMbps (%dus)- %d%sMbps (%dus)", __func__,
841 sn->num_rates,
842 DOT11RATE(0)/2, DOT11RATE(0) % 1 ? ".5" : "",
843 sn->stats[1][0].perfect_tx_time,
844 DOT11RATE(sn->num_rates-1)/2, DOT11RATE(sn->num_rates-1) % 1 ? ".5" : "",
845 sn->stats[1][sn->num_rates-1].perfect_tx_time
193b341d 846 );
493caacd
RP
847#endif
848 /* set the visible bit-rate */
849 if (sn->static_rix != -1)
850 ni->ni_txrate = DOT11RATE(sn->static_rix);
193b341d 851 else
493caacd 852 ni->ni_txrate = RATE(0);
193b341d 853#undef RATE
493caacd 854#undef DOT11RATE
193b341d
SZ
855}
856
857static void
493caacd 858sample_stats(void *arg, struct ieee80211_node *ni)
193b341d
SZ
859{
860 struct ath_softc *sc = arg;
493caacd
RP
861 const HAL_RATE_TABLE *rt = sc->sc_currates;
862 struct sample_node *sn = ATH_NODE_SAMPLE(ATH_NODE(ni));
863 uint32_t mask;
864 int rix, y;
193b341d 865
493caacd
RP
866 kprintf("\n[%6D] refcnt %d static_rix %d ratemask 0x%x\n",
867 ni->ni_macaddr, ":", ieee80211_node_refcnt(ni),
868 sn->static_rix, sn->ratemask);
869 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) {
870 kprintf("[%4u] cur rix %d since switch: packets %d ticks %u\n",
871 bin_to_size(y), sn->current_rix[y],
872 sn->packets_since_switch[y], sn->ticks_since_switch[y]);
873 kprintf("[%4u] last sample %d cur sample %d packets sent %d\n",
874 bin_to_size(y), sn->last_sample_rix[y],
875 sn->current_sample_rix[y], sn->packets_sent[y]);
876 kprintf("[%4u] packets since sample %d sample tt %u\n",
877 bin_to_size(y), sn->packets_since_sample[y],
878 sn->sample_tt[y]);
879 }
880 for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) {
881 if ((mask & 1) == 0)
882 continue;
883 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) {
884 if (sn->stats[y][rix].total_packets == 0)
885 continue;
886 kprintf("[%2u:%4u] %8d:%-8d (%3d%%) T %8d F %4d avg %5u last %u\n",
887 (rt->info[rix].dot11Rate & IEEE80211_RATE_VAL)/2,
888 bin_to_size(y),
889 sn->stats[y][rix].total_packets,
890 sn->stats[y][rix].packets_acked,
891 (100*sn->stats[y][rix].packets_acked)/sn->stats[y][rix].total_packets,
892 sn->stats[y][rix].tries,
893 sn->stats[y][rix].successive_failures,
894 sn->stats[y][rix].average_tx_time,
895 ticks - sn->stats[y][rix].last_tx);
896 }
897 }
193b341d
SZ
898}
899
493caacd
RP
900static int
901ath_rate_sysctl_stats(SYSCTL_HANDLER_ARGS)
193b341d 902{
493caacd
RP
903 struct ath_softc *sc = arg1;
904 struct ifnet *ifp = sc->sc_ifp;
905 struct ieee80211com *ic = ifp->if_l2com;
906 int error, v;
907
908 v = 0;
909 error = sysctl_handle_int(oidp, &v, 0, req);
910 if (error || !req->newptr)
911 return error;
912 ieee80211_iterate_nodes(&ic->ic_sta, sample_stats, sc);
913 return 0;
914}
193b341d 915
493caacd
RP
916static int
917ath_rate_sysctl_smoothing_rate(SYSCTL_HANDLER_ARGS)
918{
919 struct sample_softc *ssc = arg1;
920 int rate, error;
921
922 rate = ssc->smoothing_rate;
923 error = sysctl_handle_int(oidp, &rate, 0, req);
924 if (error || !req->newptr)
925 return error;
926 if (!(0 <= rate && rate < 100))
927 return EINVAL;
928 ssc->smoothing_rate = rate;
929 ssc->smoothing_minpackets = 100 / (100 - rate);
930 return 0;
931}
193b341d 932
493caacd
RP
933static int
934ath_rate_sysctl_sample_rate(SYSCTL_HANDLER_ARGS)
935{
936 struct sample_softc *ssc = arg1;
937 int rate, error;
938
939 rate = ssc->sample_rate;
940 error = sysctl_handle_int(oidp, &rate, 0, req);
941 if (error || !req->newptr)
942 return error;
943 if (!(2 <= rate && rate <= 100))
944 return EINVAL;
945 ssc->sample_rate = rate;
946 return 0;
193b341d
SZ
947}
948
949static void
493caacd 950ath_rate_sysctlattach(struct ath_softc *sc, struct sample_softc *ssc)
193b341d 951{
493caacd
RP
952 struct sysctl_ctx_list *ctx;
953 struct sysctl_oid *tree;
954
955 ctx = &sc->sc_sysctl_ctx;
09da298d 956 tree = sc->sc_sysctl_tree;
493caacd
RP
957 if (tree == NULL) {
958 device_printf(sc->sc_dev, "can't add sysctl node\n");
959 return;
960 }
961 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
962 "smoothing_rate", CTLTYPE_INT | CTLFLAG_RW, ssc, 0,
963 ath_rate_sysctl_smoothing_rate, "I",
964 "sample: smoothing rate for avg tx time (%%)");
965 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
966 "sample_rate", CTLTYPE_INT | CTLFLAG_RW, ssc, 0,
967 ath_rate_sysctl_sample_rate, "I",
968 "sample: percent air time devoted to sampling new rates (%%)");
969 /* XXX max_successive_failures, stale_failure_timeout, min_switch */
970 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
971 "sample_stats", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
972 ath_rate_sysctl_stats, "I", "sample: print statistics");
193b341d
SZ
973}
974
975struct ath_ratectrl *
976ath_rate_attach(struct ath_softc *sc)
977{
493caacd 978 struct sample_softc *ssc;
193b341d 979
493caacd
RP
980 ssc = kmalloc(sizeof(struct sample_softc), M_DEVBUF, M_NOWAIT|M_ZERO);
981 if (ssc == NULL)
193b341d 982 return NULL;
493caacd
RP
983 ssc->arc.arc_space = sizeof(struct sample_node);
984 ssc->smoothing_rate = 95; /* ewma percentage ([0..99]) */
985 ssc->smoothing_minpackets = 100 / (100 - ssc->smoothing_rate);
986 ssc->sample_rate = 10; /* %time to try diff tx rates */
987 ssc->max_successive_failures = 3; /* threshold for rate sampling*/
988 ssc->stale_failure_timeout = 10 * hz; /* 10 seconds */
989 ssc->min_switch = hz; /* 1 second */
990 ath_rate_sysctlattach(sc, ssc);
991 return &ssc->arc;
193b341d
SZ
992}
993
994void
995ath_rate_detach(struct ath_ratectrl *arc)
996{
493caacd 997 struct sample_softc *ssc = (struct sample_softc *) arc;
193b341d 998
493caacd 999 kfree(ssc, M_DEVBUF);
193b341d 1000}