1 /*-
2 * Copyright (c) 2004 INRIA
3 * Copyright (c) 2002-2005 Sam Leffler, Errno Consulting
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer,
11 * without modification.
12 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
13 * similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
14 * redistribution must be conditioned upon including a substantially
15 * similar Disclaimer requirement for further binary redistribution.
16 * 3. Neither the names of the above-listed copyright holders nor the names
17 * of any contributors may be used to endorse or promote products derived
18 * from this software without specific prior written permission.
19 *
20 * Alternatively, this software may be distributed under the terms of the
21 * GNU General Public License ("GPL") version 2 as published by the Free
22 * Software Foundation.
23 *
24 * NO WARRANTY
25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
26 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
27 * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTABILITY
28 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
29 * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
30 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
33 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
35 * THE POSSIBILITY OF SUCH DAMAGES.
36 *
37 */
38
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
41
42 /*
43 * AMRR rate control. See:
44 * http://www-sop.inria.fr/rapports/sophia/RR-5208.html
45 * "IEEE 802.11 Rate Adaptation: A Practical Approach" by
46 * Mathieu Lacage, Hossein Manshaei, Thierry Turletti
47 */
48 #include "opt_ath.h"
49 #include "opt_inet.h"
50 #include "opt_wlan.h"
51
52 #include <sys/param.h>
53 #include <sys/systm.h>
54 #include <sys/sysctl.h>
55 #include <sys/kernel.h>
56 #include <sys/lock.h>
57 #include <sys/errno.h>
58
59 #if defined(__DragonFly__)
60 /* empty */
61 #else
62 #include <machine/bus.h>
63 #include <machine/resource.h>
64 #endif
65 #include <sys/bus.h>
66
67 #include <sys/socket.h>
68
69 #include <net/if.h>
70 #include <net/if_media.h>
71 #include <net/if_arp.h>
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/amrr/amrr.h>
84 #include <dev/netif/ath/ath_hal/ah_desc.h>
85
86 static int ath_rateinterval = 1000; /* rate ctl interval (ms) */
87 static int ath_rate_max_success_threshold = 10;
88 static int ath_rate_min_success_threshold = 1;
89
90 static void ath_rate_update(struct ath_softc *, struct ieee80211_node *,
91 int rate);
92 static void ath_rate_ctl_start(struct ath_softc *, struct ieee80211_node *);
93 static void ath_rate_ctl(void *, struct ieee80211_node *);
94
95 void
ath_rate_node_init(struct ath_softc * sc,struct ath_node * an)96 ath_rate_node_init(struct ath_softc *sc, struct ath_node *an)
97 {
98 /* NB: assumed to be zero'd by caller */
99 }
100
101 void
ath_rate_node_cleanup(struct ath_softc * sc,struct ath_node * an)102 ath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an)
103 {
104 }
105
106 void
ath_rate_findrate(struct ath_softc * sc,struct ath_node * an,int shortPreamble,size_t frameLen,u_int8_t * rix,int * try0,u_int8_t * txrate)107 ath_rate_findrate(struct ath_softc *sc, struct ath_node *an,
108 int shortPreamble, size_t frameLen,
109 u_int8_t *rix, int *try0, u_int8_t *txrate)
110 {
111 struct amrr_node *amn = ATH_NODE_AMRR(an);
112
113 *rix = amn->amn_tx_rix0;
114 *try0 = amn->amn_tx_try0;
115 if (shortPreamble)
116 *txrate = amn->amn_tx_rate0sp;
117 else
118 *txrate = amn->amn_tx_rate0;
119 }
120
121 /*
122 * Get the TX rates.
123 *
124 * The short preamble bits aren't set here; the caller should augment
125 * the returned rate with the relevant preamble rate flag.
126 */
127 void
ath_rate_getxtxrates(struct ath_softc * sc,struct ath_node * an,uint8_t rix0,struct ath_rc_series * rc)128 ath_rate_getxtxrates(struct ath_softc *sc, struct ath_node *an,
129 uint8_t rix0, struct ath_rc_series *rc)
130 {
131 struct amrr_node *amn = ATH_NODE_AMRR(an);
132
133 rc[0].flags = rc[1].flags = rc[2].flags = rc[3].flags = 0;
134
135 rc[0].rix = amn->amn_tx_rate0;
136 rc[1].rix = amn->amn_tx_rate1;
137 rc[2].rix = amn->amn_tx_rate2;
138 rc[3].rix = amn->amn_tx_rate3;
139
140 rc[0].tries = amn->amn_tx_try0;
141 rc[1].tries = amn->amn_tx_try1;
142 rc[2].tries = amn->amn_tx_try2;
143 rc[3].tries = amn->amn_tx_try3;
144 }
145
146
147 void
ath_rate_setupxtxdesc(struct ath_softc * sc,struct ath_node * an,struct ath_desc * ds,int shortPreamble,u_int8_t rix)148 ath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an,
149 struct ath_desc *ds, int shortPreamble, u_int8_t rix)
150 {
151 struct amrr_node *amn = ATH_NODE_AMRR(an);
152
153 ath_hal_setupxtxdesc(sc->sc_ah, ds
154 , amn->amn_tx_rate1sp, amn->amn_tx_try1 /* series 1 */
155 , amn->amn_tx_rate2sp, amn->amn_tx_try2 /* series 2 */
156 , amn->amn_tx_rate3sp, amn->amn_tx_try3 /* series 3 */
157 );
158 }
159
160 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)161 ath_rate_tx_complete(struct ath_softc *sc, struct ath_node *an,
162 const struct ath_rc_series *rc, const struct ath_tx_status *ts,
163 int frame_size, int nframes, int nbad)
164 {
165 struct amrr_node *amn = ATH_NODE_AMRR(an);
166 int sr = ts->ts_shortretry;
167 int lr = ts->ts_longretry;
168 int retry_count = sr + lr;
169
170 amn->amn_tx_try0_cnt++;
171 if (retry_count == 1) {
172 amn->amn_tx_try1_cnt++;
173 } else if (retry_count == 2) {
174 amn->amn_tx_try1_cnt++;
175 amn->amn_tx_try2_cnt++;
176 } else if (retry_count == 3) {
177 amn->amn_tx_try1_cnt++;
178 amn->amn_tx_try2_cnt++;
179 amn->amn_tx_try3_cnt++;
180 } else if (retry_count > 3) {
181 amn->amn_tx_try1_cnt++;
182 amn->amn_tx_try2_cnt++;
183 amn->amn_tx_try3_cnt++;
184 amn->amn_tx_failure_cnt++;
185 }
186 if (amn->amn_interval != 0 &&
187 ticks - amn->amn_ticks > amn->amn_interval) {
188 ath_rate_ctl(sc, &an->an_node);
189 amn->amn_ticks = ticks;
190 }
191 }
192
193 void
ath_rate_newassoc(struct ath_softc * sc,struct ath_node * an,int isnew)194 ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew)
195 {
196 if (isnew)
197 ath_rate_ctl_start(sc, &an->an_node);
198 }
199
200 static void
node_reset(struct amrr_node * amn)201 node_reset(struct amrr_node *amn)
202 {
203 amn->amn_tx_try0_cnt = 0;
204 amn->amn_tx_try1_cnt = 0;
205 amn->amn_tx_try2_cnt = 0;
206 amn->amn_tx_try3_cnt = 0;
207 amn->amn_tx_failure_cnt = 0;
208 amn->amn_success = 0;
209 amn->amn_recovery = 0;
210 amn->amn_success_threshold = ath_rate_min_success_threshold;
211 }
212
213
214 /**
215 * The code below assumes that we are dealing with hardware multi rate retry
216 * I have no idea what will happen if you try to use this module with another
217 * type of hardware. Your machine might catch fire or it might work with
218 * horrible performance...
219 */
220 static void
ath_rate_update(struct ath_softc * sc,struct ieee80211_node * ni,int rate)221 ath_rate_update(struct ath_softc *sc, struct ieee80211_node *ni, int rate)
222 {
223 struct ath_node *an = ATH_NODE(ni);
224 struct amrr_node *amn = ATH_NODE_AMRR(an);
225 struct ieee80211vap *vap = ni->ni_vap;
226 const HAL_RATE_TABLE *rt = sc->sc_currates;
227 u_int8_t rix;
228
229 KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode));
230
231 IEEE80211_NOTE(vap, IEEE80211_MSG_RATECTL, ni,
232 "%s: set xmit rate to %dM", __func__,
233 ni->ni_rates.rs_nrates > 0 ?
234 (ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL) / 2 : 0);
235
236 amn->amn_rix = rate;
237 /*
238 * Before associating a node has no rate set setup
239 * so we can't calculate any transmit codes to use.
240 * This is ok since we should never be sending anything
241 * but management frames and those always go at the
242 * lowest hardware rate.
243 */
244 if (ni->ni_rates.rs_nrates > 0) {
245 ni->ni_txrate = ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL;
246 amn->amn_tx_rix0 = sc->sc_rixmap[ni->ni_txrate];
247 amn->amn_tx_rate0 = rt->info[amn->amn_tx_rix0].rateCode;
248 amn->amn_tx_rate0sp = amn->amn_tx_rate0 |
249 rt->info[amn->amn_tx_rix0].shortPreamble;
250 if (sc->sc_mrretry) {
251 amn->amn_tx_try0 = 1;
252 amn->amn_tx_try1 = 1;
253 amn->amn_tx_try2 = 1;
254 amn->amn_tx_try3 = 1;
255 if (--rate >= 0) {
256 rix = sc->sc_rixmap[
257 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL];
258 amn->amn_tx_rate1 = rt->info[rix].rateCode;
259 amn->amn_tx_rate1sp = amn->amn_tx_rate1 |
260 rt->info[rix].shortPreamble;
261 } else {
262 amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0;
263 }
264 if (--rate >= 0) {
265 rix = sc->sc_rixmap[
266 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL];
267 amn->amn_tx_rate2 = rt->info[rix].rateCode;
268 amn->amn_tx_rate2sp = amn->amn_tx_rate2 |
269 rt->info[rix].shortPreamble;
270 } else {
271 amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0;
272 }
273 if (rate > 0) {
274 /* NB: only do this if we didn't already do it above */
275 amn->amn_tx_rate3 = rt->info[0].rateCode;
276 amn->amn_tx_rate3sp =
277 amn->amn_tx_rate3 | rt->info[0].shortPreamble;
278 } else {
279 amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0;
280 }
281 } else {
282 amn->amn_tx_try0 = ATH_TXMAXTRY;
283 /* theorically, these statements are useless because
284 * the code which uses them tests for an_tx_try0 == ATH_TXMAXTRY
285 */
286 amn->amn_tx_try1 = 0;
287 amn->amn_tx_try2 = 0;
288 amn->amn_tx_try3 = 0;
289 amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0;
290 amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0;
291 amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0;
292 }
293 }
294 node_reset(amn);
295
296 amn->amn_interval = ath_rateinterval;
297 if (vap->iv_opmode == IEEE80211_M_STA)
298 amn->amn_interval /= 2;
299 amn->amn_interval = (amn->amn_interval * hz) / 1000;
300 }
301
302 /*
303 * Set the starting transmit rate for a node.
304 */
305 static void
ath_rate_ctl_start(struct ath_softc * sc,struct ieee80211_node * ni)306 ath_rate_ctl_start(struct ath_softc *sc, struct ieee80211_node *ni)
307 {
308 #define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL)
309 const struct ieee80211_txparam *tp = ni->ni_txparms;
310 int srate;
311
312 KASSERT(ni->ni_rates.rs_nrates > 0, ("no rates"));
313 if (tp == NULL || tp->ucastrate == IEEE80211_FIXED_RATE_NONE) {
314 /*
315 * No fixed rate is requested. For 11b start with
316 * the highest negotiated rate; otherwise, for 11g
317 * and 11a, we start "in the middle" at 24Mb or 36Mb.
318 */
319 srate = ni->ni_rates.rs_nrates - 1;
320 if (sc->sc_curmode != IEEE80211_MODE_11B) {
321 /*
322 * Scan the negotiated rate set to find the
323 * closest rate.
324 */
325 /* NB: the rate set is assumed sorted */
326 for (; srate >= 0 && RATE(srate) > 72; srate--)
327 ;
328 }
329 } else {
330 /*
331 * A fixed rate is to be used; ic_fixed_rate is the
332 * IEEE code for this rate (sans basic bit). Convert this
333 * to the index into the negotiated rate set for
334 * the node. We know the rate is there because the
335 * rate set is checked when the station associates.
336 */
337 /* NB: the rate set is assumed sorted */
338 srate = ni->ni_rates.rs_nrates - 1;
339 for (; srate >= 0 && RATE(srate) != tp->ucastrate; srate--)
340 ;
341 }
342 /*
343 * The selected rate may not be available due to races
344 * and mode settings. Also orphaned nodes created in
345 * adhoc mode may not have any rate set so this lookup
346 * can fail. This is not fatal.
347 */
348 ath_rate_update(sc, ni, srate < 0 ? 0 : srate);
349 #undef RATE
350 }
351
352 /*
353 * Examine and potentially adjust the transmit rate.
354 */
355 static void
ath_rate_ctl(void * arg,struct ieee80211_node * ni)356 ath_rate_ctl(void *arg, struct ieee80211_node *ni)
357 {
358 struct ath_softc *sc = arg;
359 struct amrr_node *amn = ATH_NODE_AMRR(ATH_NODE (ni));
360 int rix;
361
362 #define is_success(amn) \
363 (amn->amn_tx_try1_cnt < (amn->amn_tx_try0_cnt/10))
364 #define is_enough(amn) \
365 (amn->amn_tx_try0_cnt > 10)
366 #define is_failure(amn) \
367 (amn->amn_tx_try1_cnt > (amn->amn_tx_try0_cnt/3))
368
369 rix = amn->amn_rix;
370
371 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni,
372 "cnt0: %d cnt1: %d cnt2: %d cnt3: %d -- threshold: %d",
373 amn->amn_tx_try0_cnt, amn->amn_tx_try1_cnt, amn->amn_tx_try2_cnt,
374 amn->amn_tx_try3_cnt, amn->amn_success_threshold);
375 if (is_success (amn) && is_enough (amn)) {
376 amn->amn_success++;
377 if (amn->amn_success == amn->amn_success_threshold &&
378 rix + 1 < ni->ni_rates.rs_nrates) {
379 amn->amn_recovery = 1;
380 amn->amn_success = 0;
381 rix++;
382 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni,
383 "increase rate to %d", rix);
384 } else {
385 amn->amn_recovery = 0;
386 }
387 } else if (is_failure (amn)) {
388 amn->amn_success = 0;
389 if (rix > 0) {
390 if (amn->amn_recovery) {
391 /* recovery failure. */
392 amn->amn_success_threshold *= 2;
393 amn->amn_success_threshold = min (amn->amn_success_threshold,
394 (u_int)ath_rate_max_success_threshold);
395 IEEE80211_NOTE(ni->ni_vap,
396 IEEE80211_MSG_RATECTL, ni,
397 "decrease rate recovery thr: %d",
398 amn->amn_success_threshold);
399 } else {
400 /* simple failure. */
401 amn->amn_success_threshold = ath_rate_min_success_threshold;
402 IEEE80211_NOTE(ni->ni_vap,
403 IEEE80211_MSG_RATECTL, ni,
404 "decrease rate normal thr: %d",
405 amn->amn_success_threshold);
406 }
407 amn->amn_recovery = 0;
408 rix--;
409 } else {
410 amn->amn_recovery = 0;
411 }
412
413 }
414 if (is_enough (amn) || rix != amn->amn_rix) {
415 /* reset counters. */
416 amn->amn_tx_try0_cnt = 0;
417 amn->amn_tx_try1_cnt = 0;
418 amn->amn_tx_try2_cnt = 0;
419 amn->amn_tx_try3_cnt = 0;
420 amn->amn_tx_failure_cnt = 0;
421 }
422 if (rix != amn->amn_rix) {
423 ath_rate_update(sc, ni, rix);
424 }
425 }
426
427 static int
ath_rate_fetch_node_stats(struct ath_softc * sc,struct ath_node * an,struct ath_rateioctl * re)428 ath_rate_fetch_node_stats(struct ath_softc *sc, struct ath_node *an,
429 struct ath_rateioctl *re)
430 {
431
432 return (EINVAL);
433 }
434
435 static void
ath_rate_sysctlattach(struct ath_softc * sc)436 ath_rate_sysctlattach(struct ath_softc *sc)
437 {
438 struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev);
439 struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev);
440
441 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
442 "rate_interval", CTLFLAG_RW, &ath_rateinterval, 0,
443 "rate control: operation interval (ms)");
444 /* XXX bounds check values */
445 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
446 "max_sucess_threshold", CTLFLAG_RW,
447 &ath_rate_max_success_threshold, 0, "");
448 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
449 "min_sucess_threshold", CTLFLAG_RW,
450 &ath_rate_min_success_threshold, 0, "");
451 }
452
453 struct ath_ratectrl *
ath_rate_attach(struct ath_softc * sc)454 ath_rate_attach(struct ath_softc *sc)
455 {
456 struct amrr_softc *asc;
457
458 asc = kmalloc(sizeof(struct amrr_softc), M_DEVBUF, M_INTWAIT|M_ZERO);
459 if (asc == NULL)
460 return NULL;
461 asc->arc.arc_space = sizeof(struct amrr_node);
462 ath_rate_sysctlattach(sc);
463
464 return &asc->arc;
465 }
466
467 void
ath_rate_detach(struct ath_ratectrl * arc)468 ath_rate_detach(struct ath_ratectrl *arc)
469 {
470 struct amrr_softc *asc = (struct amrr_softc *) arc;
471
472 kfree(asc, M_DEVBUF);
473 }
474
475 #if defined(__DragonFly__)
476
477 /*
478 * Module glue.
479 */
480 static int
amrr_modevent(module_t mod,int type,void * unused)481 amrr_modevent(module_t mod, int type, void *unused)
482 {
483 int error;
484
485 wlan_serialize_enter();
486
487 switch (type) {
488 case MOD_LOAD:
489 if (bootverbose) {
490 kprintf("ath_rate: <AMRR rate control "
491 "algorithm> version 0.1\n");
492 }
493 error = 0;
494 break;
495 case MOD_UNLOAD:
496 error = 0;
497 break;
498 default:
499 error = EINVAL;
500 break;
501 }
502 wlan_serialize_exit();
503
504 return error;
505 }
506
507 static moduledata_t amrr_mod = {
508 "ath_rate",
509 amrr_modevent,
510 0
511 };
512
513 DECLARE_MODULE(ath_rate, amrr_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
514 MODULE_VERSION(ath_rate, 1);
515 MODULE_DEPEND(ath_rate, ath_hal, 1, 1, 1);
516 MODULE_DEPEND(ath_rate, wlan, 1, 1, 1);
517
518 #endif
519