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_inet.h"
49
50#include <sys/param.h>
51#include <sys/systm.h>
52#include <sys/sysctl.h>
53#include <sys/module.h>
54#include <sys/kernel.h>
55#include <sys/lock.h>
56#include <sys/mutex.h>
57#include <sys/errno.h>
58
59#include <machine/bus.h>
60#include <machine/resource.h>
61#include <sys/bus.h>
62
63#include <sys/socket.h>
64
65#include <net/if.h>
66#include <net/if_media.h>
67#include <net/if_arp.h>
68#include <net/ethernet.h> /* XXX for ether_sprintf */
69
70#include <net80211/ieee80211_var.h>
71
72#include <net/bpf.h>
73
74#ifdef INET
75#include <netinet/in.h>
76#include <netinet/if_ether.h>
77#endif
78
79#include <dev/ath/if_athvar.h>
80#include <dev/ath/ath_rate/amrr/amrr.h>
81#include <contrib/dev/ath/ah_desc.h>
82
83#define AMRR_DEBUG
84#ifdef AMRR_DEBUG
85#define DPRINTF(sc, _fmt, ...) do { \
86 if (sc->sc_debug & 0x10) \
87 printf(_fmt, __VA_ARGS__); \
88} while (0)
89#else
90#define DPRINTF(sc, _fmt, ...)
91#endif
92
93static int ath_rateinterval = 1000; /* rate ctl interval (ms) */
94static int ath_rate_max_success_threshold = 10;
95static int ath_rate_min_success_threshold = 1;
96
97static void ath_ratectl(void *);
98static void ath_rate_update(struct ath_softc *, struct ieee80211_node *,
99 int rate);
100static void ath_rate_ctl_start(struct ath_softc *, struct ieee80211_node *);
101static void ath_rate_ctl(void *, struct ieee80211_node *);
102
103void
104ath_rate_node_init(struct ath_softc *sc, struct ath_node *an)
105{
106 /* NB: assumed to be zero'd by caller */
107 ath_rate_update(sc, &an->an_node, 0);
108}
109
110void
111ath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an)
112{
113}
114
115void
116ath_rate_findrate(struct ath_softc *sc, struct ath_node *an,
117 HAL_BOOL shortPreamble, size_t frameLen,
118 u_int8_t *rix, int *try0, u_int8_t *txrate)
119{
120 struct amrr_node *amn = ATH_NODE_AMRR(an);
121
122 *rix = amn->amn_tx_rix0;
123 *try0 = amn->amn_tx_try0;
124 if (shortPreamble)
125 *txrate = amn->amn_tx_rate0sp;
126 else
127 *txrate = amn->amn_tx_rate0;
128}
129
130void
131ath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an,
132 struct ath_desc *ds, HAL_BOOL shortPreamble, u_int8_t rix)
133{
134 struct amrr_node *amn = ATH_NODE_AMRR(an);
135
136 ath_hal_setupxtxdesc(sc->sc_ah, ds
137 , amn->amn_tx_rate1sp, amn->amn_tx_try1 /* series 1 */
138 , amn->amn_tx_rate2sp, amn->amn_tx_try2 /* series 2 */
139 , amn->amn_tx_rate3sp, amn->amn_tx_try3 /* series 3 */
140 );
141}
142
143void
144ath_rate_tx_complete(struct ath_softc *sc,
145 struct ath_node *an, const struct ath_desc *ds)
146{
147 struct amrr_node *amn = ATH_NODE_AMRR(an);
148 int sr = ds->ds_txstat.ts_shortretry;
149 int lr = ds->ds_txstat.ts_longretry;
150 int retry_count = sr + lr;
151
152 amn->amn_tx_try0_cnt++;
153 if (retry_count == 1) {
154 amn->amn_tx_try1_cnt++;
155 } else if (retry_count == 2) {
156 amn->amn_tx_try1_cnt++;
157 amn->amn_tx_try2_cnt++;
158 } else if (retry_count == 3) {
159 amn->amn_tx_try1_cnt++;
160 amn->amn_tx_try2_cnt++;
161 amn->amn_tx_try3_cnt++;
162 } else if (retry_count > 3) {
163 amn->amn_tx_try1_cnt++;
164 amn->amn_tx_try2_cnt++;
165 amn->amn_tx_try3_cnt++;
166 amn->amn_tx_failure_cnt++;
167 }
168}
169
170void
171ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew)
172{
173 if (isnew)
174 ath_rate_ctl_start(sc, &an->an_node);
175}
176
177static void
178node_reset (struct amrr_node *amn)
179{
180 amn->amn_tx_try0_cnt = 0;
181 amn->amn_tx_try1_cnt = 0;
182 amn->amn_tx_try2_cnt = 0;
183 amn->amn_tx_try3_cnt = 0;
184 amn->amn_tx_failure_cnt = 0;
185 amn->amn_success = 0;
186 amn->amn_recovery = 0;
187 amn->amn_success_threshold = ath_rate_min_success_threshold;
188}
189
190
191/**
192 * The code below assumes that we are dealing with hardware multi rate retry
193 * I have no idea what will happen if you try to use this module with another
194 * type of hardware. Your machine might catch fire or it might work with
195 * horrible performance...
196 */
197static void
198ath_rate_update(struct ath_softc *sc, struct ieee80211_node *ni, int rate)
199{
200 struct ath_node *an = ATH_NODE(ni);
201 struct amrr_node *amn = ATH_NODE_AMRR(an);
202 const HAL_RATE_TABLE *rt = sc->sc_currates;
203 u_int8_t rix;
204
205 KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode));
206
207 DPRINTF(sc, "%s: set xmit rate for %s to %dM\n",
208 __func__, ether_sprintf(ni->ni_macaddr),
209 ni->ni_rates.rs_nrates > 0 ?
210 (ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL) / 2 : 0);
211
212 ni->ni_txrate = rate;
213 /* XXX management/control frames always go at the lowest speed */
214 an->an_tx_mgtrate = rt->info[0].rateCode;
215 an->an_tx_mgtratesp = an->an_tx_mgtrate | rt->info[0].shortPreamble;
216 /*
217 * Before associating a node has no rate set setup
218 * so we can't calculate any transmit codes to use.
219 * This is ok since we should never be sending anything
220 * but management frames and those always go at the
221 * lowest hardware rate.
222 */
223 if (ni->ni_rates.rs_nrates > 0) {
224 amn->amn_tx_rix0 = sc->sc_rixmap[
225 ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL];
226 amn->amn_tx_rate0 = rt->info[amn->amn_tx_rix0].rateCode;
227 amn->amn_tx_rate0sp = amn->amn_tx_rate0 |
228 rt->info[amn->amn_tx_rix0].shortPreamble;
229 if (sc->sc_mrretry) {
230 amn->amn_tx_try0 = 1;
231 amn->amn_tx_try1 = 1;
232 amn->amn_tx_try2 = 1;
233 amn->amn_tx_try3 = 1;
234 if (--rate >= 0) {
235 rix = sc->sc_rixmap[
236 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL];
237 amn->amn_tx_rate1 = rt->info[rix].rateCode;
238 amn->amn_tx_rate1sp = amn->amn_tx_rate1 |
239 rt->info[rix].shortPreamble;
240 } else {
241 amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0;
242 }
243 if (--rate >= 0) {
244 rix = sc->sc_rixmap[
245 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL];
246 amn->amn_tx_rate2 = rt->info[rix].rateCode;
247 amn->amn_tx_rate2sp = amn->amn_tx_rate2 |
248 rt->info[rix].shortPreamble;
249 } else {
250 amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0;
251 }
252 if (rate > 0) {
253 /* NB: only do this if we didn't already do it above */
254 amn->amn_tx_rate3 = rt->info[0].rateCode;
255 amn->amn_tx_rate3sp =
256 an->an_tx_mgtrate | rt->info[0].shortPreamble;
257 } else {
258 amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0;
259 }
260 } else {
261 amn->amn_tx_try0 = ATH_TXMAXTRY;
262 /* theorically, these statements are useless because
263 * the code which uses them tests for an_tx_try0 == ATH_TXMAXTRY
264 */
265 amn->amn_tx_try1 = 0;
266 amn->amn_tx_try2 = 0;
267 amn->amn_tx_try3 = 0;
268 amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0;
269 amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0;
270 amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0;
271 }
272 }
273 node_reset (amn);
274}
275
276/*
277 * Set the starting transmit rate for a node.
278 */
279static void
280ath_rate_ctl_start(struct ath_softc *sc, struct ieee80211_node *ni)
281{
282#define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL)
283 struct ieee80211com *ic = &sc->sc_ic;
284 int srate;
285
286 KASSERT(ni->ni_rates.rs_nrates > 0, ("no rates"));
287 if (ic->ic_fixed_rate == -1) {
288 /*
289 * No fixed rate is requested. For 11b start with
290 * the highest negotiated rate; otherwise, for 11g
291 * and 11a, we start "in the middle" at 24Mb or 36Mb.
292 */
293 srate = ni->ni_rates.rs_nrates - 1;
294 if (sc->sc_curmode != IEEE80211_MODE_11B) {
295 /*
296 * Scan the negotiated rate set to find the
297 * closest rate.
298 */
299 /* NB: the rate set is assumed sorted */
300 for (; srate >= 0 && RATE(srate) > 72; srate--)
301 ;
302 KASSERT(srate >= 0, ("bogus rate set"));
303 }
304 } else {
305 /*
306 * A fixed rate is to be used; ic_fixed_rate is an
307 * index into the supported rate set. Convert this
308 * to the index into the negotiated rate set for
309 * the node. We know the rate is there because the
310 * rate set is checked when the station associates.
311 */
312 const struct ieee80211_rateset *rs =
313 &ic->ic_sup_rates[ic->ic_curmode];
314 int r = rs->rs_rates[ic->ic_fixed_rate] & IEEE80211_RATE_VAL;
315 /* NB: the rate set is assumed sorted */
316 srate = ni->ni_rates.rs_nrates - 1;
317 for (; srate >= 0 && RATE(srate) != r; srate--)
318 ;
319 KASSERT(srate >= 0,
320 ("fixed rate %d not in rate set", ic->ic_fixed_rate));
321 }
322 ath_rate_update(sc, ni, srate);
323#undef RATE
324}
325
326static void
327ath_rate_cb(void *arg, struct ieee80211_node *ni)
328{
329 ath_rate_update(ni->ni_ic->ic_ifp->if_softc, ni, (int)(uintptr_t) arg);
330}
331
332/*
333 * Reset the rate control state for each 802.11 state transition.
334 */
335void
336ath_rate_newstate(struct ath_softc *sc, enum ieee80211_state state)
337{
338 struct amrr_softc *asc = (struct amrr_softc *) sc->sc_rc;
339 struct ieee80211com *ic = &sc->sc_ic;
340 struct ieee80211_node *ni;
341
342 if (state == IEEE80211_S_INIT) {
343 callout_stop(&asc->timer);
344 return;
345 }
346 if (ic->ic_opmode == IEEE80211_M_STA) {
347 /*
348 * Reset local xmit state; this is really only
349 * meaningful when operating in station mode.
350 */
351 ni = ic->ic_bss;
352 if (state == IEEE80211_S_RUN) {
353 ath_rate_ctl_start(sc, ni);
354 } else {
355 ath_rate_update(sc, ni, 0);
356 }
357 } else {
358 /*
359 * When operating as a station the node table holds
360 * the AP's that were discovered during scanning.
361 * For any other operating mode we want to reset the
362 * tx rate state of each node.
363 */
364 if (ic->ic_sta != NULL)
365 ieee80211_iterate_nodes(ic->ic_sta, ath_rate_cb, 0);
366 ath_rate_update(sc, ic->ic_bss, 0);
367 }
368 if (ic->ic_fixed_rate == -1 && state == IEEE80211_S_RUN) {
369 int interval;
370 /*
371 * Start the background rate control thread if we
372 * are not configured to use a fixed xmit rate.
373 */
374 interval = ath_rateinterval;
375 if (ic->ic_opmode == IEEE80211_M_STA)
376 interval /= 2;
377 callout_reset(&asc->timer, (interval * hz) / 1000,
378 ath_ratectl, &sc->sc_if);
379 }
380}
381
382/*
383 * Examine and potentially adjust the transmit rate.
384 */
385static void
386ath_rate_ctl(void *arg, struct ieee80211_node *ni)
387{
388 struct ath_softc *sc = arg;
389 struct amrr_node *amn = ATH_NODE_AMRR(ATH_NODE (ni));
390 int old_rate;
391
392#define is_success(amn) \
393(amn->amn_tx_try1_cnt < (amn->amn_tx_try0_cnt/10))
394#define is_enough(amn) \
395(amn->amn_tx_try0_cnt > 10)
396#define is_failure(amn) \
397(amn->amn_tx_try1_cnt > (amn->amn_tx_try0_cnt/3))
398#define is_max_rate(ni) \
399((ni->ni_txrate + 1) >= ni->ni_rates.rs_nrates)
400#define is_min_rate(ni) \
401(ni->ni_txrate == 0)
402
403 old_rate = ni->ni_txrate;
404
405 DPRINTF (sc, "cnt0: %d cnt1: %d cnt2: %d cnt3: %d -- threshold: %d\n",
406 amn->amn_tx_try0_cnt,
407 amn->amn_tx_try1_cnt,
408 amn->amn_tx_try2_cnt,
409 amn->amn_tx_try3_cnt,
410 amn->amn_success_threshold);
411 if (is_success (amn) && is_enough (amn)) {
412 amn->amn_success++;
413 if (amn->amn_success == amn->amn_success_threshold &&
414 !is_max_rate (ni)) {
415 amn->amn_recovery = 1;
416 amn->amn_success = 0;
417 ni->ni_txrate++;
418 DPRINTF (sc, "increase rate to %d\n", ni->ni_txrate);
419 } else {
420 amn->amn_recovery = 0;
421 }
422 } else if (is_failure (amn)) {
423 amn->amn_success = 0;
424 if (!is_min_rate (ni)) {
425 if (amn->amn_recovery) {
426 /* recovery failure. */
427 amn->amn_success_threshold *= 2;
428 amn->amn_success_threshold = min (amn->amn_success_threshold,
429 (u_int)ath_rate_max_success_threshold);
430 DPRINTF (sc, "decrease rate recovery thr: %d\n", amn->amn_success_threshold);
431 } else {
432 /* simple failure. */
433 amn->amn_success_threshold = ath_rate_min_success_threshold;
434 DPRINTF (sc, "decrease rate normal thr: %d\n", amn->amn_success_threshold);
435 }
436 amn->amn_recovery = 0;
437 ni->ni_txrate--;
438 } else {
439 amn->amn_recovery = 0;
440 }
441
442 }
443 if (is_enough (amn) || old_rate != ni->ni_txrate) {
444 /* reset counters. */
445 amn->amn_tx_try0_cnt = 0;
446 amn->amn_tx_try1_cnt = 0;
447 amn->amn_tx_try2_cnt = 0;
448 amn->amn_tx_try3_cnt = 0;
449 amn->amn_tx_failure_cnt = 0;
450 }
451 if (old_rate != ni->ni_txrate) {
452 ath_rate_update(sc, ni, ni->ni_txrate);
453 }
454}
455
456static void
457ath_ratectl(void *arg)
458{
459 struct ifnet *ifp = arg;
460 struct ath_softc *sc = ifp->if_softc;
461 struct amrr_softc *asc = (struct amrr_softc *) sc->sc_rc;
462 struct ieee80211com *ic = &sc->sc_ic;
463 int interval;
464
465 if (ifp->if_flags & IFF_RUNNING) {
466 sc->sc_stats.ast_rate_calls++;
467
468 if (ic->ic_opmode == IEEE80211_M_STA)
469 ath_rate_ctl(sc, ic->ic_bss); /* NB: no reference */
470 else if (ic->ic_sta != NULL)
471 ieee80211_iterate_nodes(ic->ic_sta, ath_rate_ctl, sc);
472 }
473 interval = ath_rateinterval;
474 if (ic->ic_opmode == IEEE80211_M_STA)
475 interval /= 2;
476 callout_reset(&asc->timer, (interval * hz) / 1000,
477 ath_ratectl, &sc->sc_if);
478}
479
480static void
481ath_rate_sysctlattach(struct ath_softc *sc)
482{
483 struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev);
484 struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev);
485
486 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
487 "rate_interval", CTLFLAG_RW, &ath_rateinterval, 0,
488 "rate control: operation interval (ms)");
489 /* XXX bounds check values */
490 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
491 "max_sucess_threshold", CTLFLAG_RW,
492 &ath_rate_max_success_threshold, 0, "");
493 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
494 "min_sucess_threshold", CTLFLAG_RW,
495 &ath_rate_min_success_threshold, 0, "");
496}
497
498struct ath_ratectrl *
499ath_rate_attach(struct ath_softc *sc)
500{
501 struct amrr_softc *asc;
502
503 asc = malloc(sizeof(struct amrr_softc), M_DEVBUF, M_NOWAIT|M_ZERO);
504 if (asc == NULL)
505 return NULL;
506 asc->arc.arc_space = sizeof(struct amrr_node);
507 callout_init(&asc->timer, debug_mpsafenet ? CALLOUT_MPSAFE : 0);
508 ath_rate_sysctlattach(sc);
509
510 return &asc->arc;
511}
512
513void
514ath_rate_detach(struct ath_ratectrl *arc)
515{
516 struct amrr_softc *asc = (struct amrr_softc *) arc;
517
518 callout_drain(&asc->timer);
519 free(asc, M_DEVBUF);
520}
521
522/*
523 * Module glue.
524 */
525static int
526amrr_modevent(module_t mod, int type, void *unused)
527{
528 switch (type) {
529 case MOD_LOAD:
530 if (bootverbose)
531 printf("ath_rate: <AMRR rate control algorithm> version 0.1\n");
532 return 0;
533 case MOD_UNLOAD:
534 return 0;
535 }
536 return EINVAL;
537}
538
539static moduledata_t amrr_mod = {
540 "ath_rate",
541 amrr_modevent,
542 0
543};
544DECLARE_MODULE(ath_rate, amrr_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
545MODULE_VERSION(ath_rate, 1);
546MODULE_DEPEND(ath_rate, wlan, 1, 1, 1);
| 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_inet.h"
49
50#include <sys/param.h>
51#include <sys/systm.h>
52#include <sys/sysctl.h>
53#include <sys/module.h>
54#include <sys/kernel.h>
55#include <sys/lock.h>
56#include <sys/mutex.h>
57#include <sys/errno.h>
58
59#include <machine/bus.h>
60#include <machine/resource.h>
61#include <sys/bus.h>
62
63#include <sys/socket.h>
64
65#include <net/if.h>
66#include <net/if_media.h>
67#include <net/if_arp.h>
68#include <net/ethernet.h> /* XXX for ether_sprintf */
69
70#include <net80211/ieee80211_var.h>
71
72#include <net/bpf.h>
73
74#ifdef INET
75#include <netinet/in.h>
76#include <netinet/if_ether.h>
77#endif
78
79#include <dev/ath/if_athvar.h>
80#include <dev/ath/ath_rate/amrr/amrr.h>
81#include <contrib/dev/ath/ah_desc.h>
82
83#define AMRR_DEBUG
84#ifdef AMRR_DEBUG
85#define DPRINTF(sc, _fmt, ...) do { \
86 if (sc->sc_debug & 0x10) \
87 printf(_fmt, __VA_ARGS__); \
88} while (0)
89#else
90#define DPRINTF(sc, _fmt, ...)
91#endif
92
93static int ath_rateinterval = 1000; /* rate ctl interval (ms) */
94static int ath_rate_max_success_threshold = 10;
95static int ath_rate_min_success_threshold = 1;
96
97static void ath_ratectl(void *);
98static void ath_rate_update(struct ath_softc *, struct ieee80211_node *,
99 int rate);
100static void ath_rate_ctl_start(struct ath_softc *, struct ieee80211_node *);
101static void ath_rate_ctl(void *, struct ieee80211_node *);
102
103void
104ath_rate_node_init(struct ath_softc *sc, struct ath_node *an)
105{
106 /* NB: assumed to be zero'd by caller */
107 ath_rate_update(sc, &an->an_node, 0);
108}
109
110void
111ath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an)
112{
113}
114
115void
116ath_rate_findrate(struct ath_softc *sc, struct ath_node *an,
117 HAL_BOOL shortPreamble, size_t frameLen,
118 u_int8_t *rix, int *try0, u_int8_t *txrate)
119{
120 struct amrr_node *amn = ATH_NODE_AMRR(an);
121
122 *rix = amn->amn_tx_rix0;
123 *try0 = amn->amn_tx_try0;
124 if (shortPreamble)
125 *txrate = amn->amn_tx_rate0sp;
126 else
127 *txrate = amn->amn_tx_rate0;
128}
129
130void
131ath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an,
132 struct ath_desc *ds, HAL_BOOL shortPreamble, u_int8_t rix)
133{
134 struct amrr_node *amn = ATH_NODE_AMRR(an);
135
136 ath_hal_setupxtxdesc(sc->sc_ah, ds
137 , amn->amn_tx_rate1sp, amn->amn_tx_try1 /* series 1 */
138 , amn->amn_tx_rate2sp, amn->amn_tx_try2 /* series 2 */
139 , amn->amn_tx_rate3sp, amn->amn_tx_try3 /* series 3 */
140 );
141}
142
143void
144ath_rate_tx_complete(struct ath_softc *sc,
145 struct ath_node *an, const struct ath_desc *ds)
146{
147 struct amrr_node *amn = ATH_NODE_AMRR(an);
148 int sr = ds->ds_txstat.ts_shortretry;
149 int lr = ds->ds_txstat.ts_longretry;
150 int retry_count = sr + lr;
151
152 amn->amn_tx_try0_cnt++;
153 if (retry_count == 1) {
154 amn->amn_tx_try1_cnt++;
155 } else if (retry_count == 2) {
156 amn->amn_tx_try1_cnt++;
157 amn->amn_tx_try2_cnt++;
158 } else if (retry_count == 3) {
159 amn->amn_tx_try1_cnt++;
160 amn->amn_tx_try2_cnt++;
161 amn->amn_tx_try3_cnt++;
162 } else if (retry_count > 3) {
163 amn->amn_tx_try1_cnt++;
164 amn->amn_tx_try2_cnt++;
165 amn->amn_tx_try3_cnt++;
166 amn->amn_tx_failure_cnt++;
167 }
168}
169
170void
171ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew)
172{
173 if (isnew)
174 ath_rate_ctl_start(sc, &an->an_node);
175}
176
177static void
178node_reset (struct amrr_node *amn)
179{
180 amn->amn_tx_try0_cnt = 0;
181 amn->amn_tx_try1_cnt = 0;
182 amn->amn_tx_try2_cnt = 0;
183 amn->amn_tx_try3_cnt = 0;
184 amn->amn_tx_failure_cnt = 0;
185 amn->amn_success = 0;
186 amn->amn_recovery = 0;
187 amn->amn_success_threshold = ath_rate_min_success_threshold;
188}
189
190
191/**
192 * The code below assumes that we are dealing with hardware multi rate retry
193 * I have no idea what will happen if you try to use this module with another
194 * type of hardware. Your machine might catch fire or it might work with
195 * horrible performance...
196 */
197static void
198ath_rate_update(struct ath_softc *sc, struct ieee80211_node *ni, int rate)
199{
200 struct ath_node *an = ATH_NODE(ni);
201 struct amrr_node *amn = ATH_NODE_AMRR(an);
202 const HAL_RATE_TABLE *rt = sc->sc_currates;
203 u_int8_t rix;
204
205 KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode));
206
207 DPRINTF(sc, "%s: set xmit rate for %s to %dM\n",
208 __func__, ether_sprintf(ni->ni_macaddr),
209 ni->ni_rates.rs_nrates > 0 ?
210 (ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL) / 2 : 0);
211
212 ni->ni_txrate = rate;
213 /* XXX management/control frames always go at the lowest speed */
214 an->an_tx_mgtrate = rt->info[0].rateCode;
215 an->an_tx_mgtratesp = an->an_tx_mgtrate | rt->info[0].shortPreamble;
216 /*
217 * Before associating a node has no rate set setup
218 * so we can't calculate any transmit codes to use.
219 * This is ok since we should never be sending anything
220 * but management frames and those always go at the
221 * lowest hardware rate.
222 */
223 if (ni->ni_rates.rs_nrates > 0) {
224 amn->amn_tx_rix0 = sc->sc_rixmap[
225 ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL];
226 amn->amn_tx_rate0 = rt->info[amn->amn_tx_rix0].rateCode;
227 amn->amn_tx_rate0sp = amn->amn_tx_rate0 |
228 rt->info[amn->amn_tx_rix0].shortPreamble;
229 if (sc->sc_mrretry) {
230 amn->amn_tx_try0 = 1;
231 amn->amn_tx_try1 = 1;
232 amn->amn_tx_try2 = 1;
233 amn->amn_tx_try3 = 1;
234 if (--rate >= 0) {
235 rix = sc->sc_rixmap[
236 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL];
237 amn->amn_tx_rate1 = rt->info[rix].rateCode;
238 amn->amn_tx_rate1sp = amn->amn_tx_rate1 |
239 rt->info[rix].shortPreamble;
240 } else {
241 amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0;
242 }
243 if (--rate >= 0) {
244 rix = sc->sc_rixmap[
245 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL];
246 amn->amn_tx_rate2 = rt->info[rix].rateCode;
247 amn->amn_tx_rate2sp = amn->amn_tx_rate2 |
248 rt->info[rix].shortPreamble;
249 } else {
250 amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0;
251 }
252 if (rate > 0) {
253 /* NB: only do this if we didn't already do it above */
254 amn->amn_tx_rate3 = rt->info[0].rateCode;
255 amn->amn_tx_rate3sp =
256 an->an_tx_mgtrate | rt->info[0].shortPreamble;
257 } else {
258 amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0;
259 }
260 } else {
261 amn->amn_tx_try0 = ATH_TXMAXTRY;
262 /* theorically, these statements are useless because
263 * the code which uses them tests for an_tx_try0 == ATH_TXMAXTRY
264 */
265 amn->amn_tx_try1 = 0;
266 amn->amn_tx_try2 = 0;
267 amn->amn_tx_try3 = 0;
268 amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0;
269 amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0;
270 amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0;
271 }
272 }
273 node_reset (amn);
274}
275
276/*
277 * Set the starting transmit rate for a node.
278 */
279static void
280ath_rate_ctl_start(struct ath_softc *sc, struct ieee80211_node *ni)
281{
282#define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL)
283 struct ieee80211com *ic = &sc->sc_ic;
284 int srate;
285
286 KASSERT(ni->ni_rates.rs_nrates > 0, ("no rates"));
287 if (ic->ic_fixed_rate == -1) {
288 /*
289 * No fixed rate is requested. For 11b start with
290 * the highest negotiated rate; otherwise, for 11g
291 * and 11a, we start "in the middle" at 24Mb or 36Mb.
292 */
293 srate = ni->ni_rates.rs_nrates - 1;
294 if (sc->sc_curmode != IEEE80211_MODE_11B) {
295 /*
296 * Scan the negotiated rate set to find the
297 * closest rate.
298 */
299 /* NB: the rate set is assumed sorted */
300 for (; srate >= 0 && RATE(srate) > 72; srate--)
301 ;
302 KASSERT(srate >= 0, ("bogus rate set"));
303 }
304 } else {
305 /*
306 * A fixed rate is to be used; ic_fixed_rate is an
307 * index into the supported rate set. Convert this
308 * to the index into the negotiated rate set for
309 * the node. We know the rate is there because the
310 * rate set is checked when the station associates.
311 */
312 const struct ieee80211_rateset *rs =
313 &ic->ic_sup_rates[ic->ic_curmode];
314 int r = rs->rs_rates[ic->ic_fixed_rate] & IEEE80211_RATE_VAL;
315 /* NB: the rate set is assumed sorted */
316 srate = ni->ni_rates.rs_nrates - 1;
317 for (; srate >= 0 && RATE(srate) != r; srate--)
318 ;
319 KASSERT(srate >= 0,
320 ("fixed rate %d not in rate set", ic->ic_fixed_rate));
321 }
322 ath_rate_update(sc, ni, srate);
323#undef RATE
324}
325
326static void
327ath_rate_cb(void *arg, struct ieee80211_node *ni)
328{
329 ath_rate_update(ni->ni_ic->ic_ifp->if_softc, ni, (int)(uintptr_t) arg);
330}
331
332/*
333 * Reset the rate control state for each 802.11 state transition.
334 */
335void
336ath_rate_newstate(struct ath_softc *sc, enum ieee80211_state state)
337{
338 struct amrr_softc *asc = (struct amrr_softc *) sc->sc_rc;
339 struct ieee80211com *ic = &sc->sc_ic;
340 struct ieee80211_node *ni;
341
342 if (state == IEEE80211_S_INIT) {
343 callout_stop(&asc->timer);
344 return;
345 }
346 if (ic->ic_opmode == IEEE80211_M_STA) {
347 /*
348 * Reset local xmit state; this is really only
349 * meaningful when operating in station mode.
350 */
351 ni = ic->ic_bss;
352 if (state == IEEE80211_S_RUN) {
353 ath_rate_ctl_start(sc, ni);
354 } else {
355 ath_rate_update(sc, ni, 0);
356 }
357 } else {
358 /*
359 * When operating as a station the node table holds
360 * the AP's that were discovered during scanning.
361 * For any other operating mode we want to reset the
362 * tx rate state of each node.
363 */
364 if (ic->ic_sta != NULL)
365 ieee80211_iterate_nodes(ic->ic_sta, ath_rate_cb, 0);
366 ath_rate_update(sc, ic->ic_bss, 0);
367 }
368 if (ic->ic_fixed_rate == -1 && state == IEEE80211_S_RUN) {
369 int interval;
370 /*
371 * Start the background rate control thread if we
372 * are not configured to use a fixed xmit rate.
373 */
374 interval = ath_rateinterval;
375 if (ic->ic_opmode == IEEE80211_M_STA)
376 interval /= 2;
377 callout_reset(&asc->timer, (interval * hz) / 1000,
378 ath_ratectl, &sc->sc_if);
379 }
380}
381
382/*
383 * Examine and potentially adjust the transmit rate.
384 */
385static void
386ath_rate_ctl(void *arg, struct ieee80211_node *ni)
387{
388 struct ath_softc *sc = arg;
389 struct amrr_node *amn = ATH_NODE_AMRR(ATH_NODE (ni));
390 int old_rate;
391
392#define is_success(amn) \
393(amn->amn_tx_try1_cnt < (amn->amn_tx_try0_cnt/10))
394#define is_enough(amn) \
395(amn->amn_tx_try0_cnt > 10)
396#define is_failure(amn) \
397(amn->amn_tx_try1_cnt > (amn->amn_tx_try0_cnt/3))
398#define is_max_rate(ni) \
399((ni->ni_txrate + 1) >= ni->ni_rates.rs_nrates)
400#define is_min_rate(ni) \
401(ni->ni_txrate == 0)
402
403 old_rate = ni->ni_txrate;
404
405 DPRINTF (sc, "cnt0: %d cnt1: %d cnt2: %d cnt3: %d -- threshold: %d\n",
406 amn->amn_tx_try0_cnt,
407 amn->amn_tx_try1_cnt,
408 amn->amn_tx_try2_cnt,
409 amn->amn_tx_try3_cnt,
410 amn->amn_success_threshold);
411 if (is_success (amn) && is_enough (amn)) {
412 amn->amn_success++;
413 if (amn->amn_success == amn->amn_success_threshold &&
414 !is_max_rate (ni)) {
415 amn->amn_recovery = 1;
416 amn->amn_success = 0;
417 ni->ni_txrate++;
418 DPRINTF (sc, "increase rate to %d\n", ni->ni_txrate);
419 } else {
420 amn->amn_recovery = 0;
421 }
422 } else if (is_failure (amn)) {
423 amn->amn_success = 0;
424 if (!is_min_rate (ni)) {
425 if (amn->amn_recovery) {
426 /* recovery failure. */
427 amn->amn_success_threshold *= 2;
428 amn->amn_success_threshold = min (amn->amn_success_threshold,
429 (u_int)ath_rate_max_success_threshold);
430 DPRINTF (sc, "decrease rate recovery thr: %d\n", amn->amn_success_threshold);
431 } else {
432 /* simple failure. */
433 amn->amn_success_threshold = ath_rate_min_success_threshold;
434 DPRINTF (sc, "decrease rate normal thr: %d\n", amn->amn_success_threshold);
435 }
436 amn->amn_recovery = 0;
437 ni->ni_txrate--;
438 } else {
439 amn->amn_recovery = 0;
440 }
441
442 }
443 if (is_enough (amn) || old_rate != ni->ni_txrate) {
444 /* reset counters. */
445 amn->amn_tx_try0_cnt = 0;
446 amn->amn_tx_try1_cnt = 0;
447 amn->amn_tx_try2_cnt = 0;
448 amn->amn_tx_try3_cnt = 0;
449 amn->amn_tx_failure_cnt = 0;
450 }
451 if (old_rate != ni->ni_txrate) {
452 ath_rate_update(sc, ni, ni->ni_txrate);
453 }
454}
455
456static void
457ath_ratectl(void *arg)
458{
459 struct ifnet *ifp = arg;
460 struct ath_softc *sc = ifp->if_softc;
461 struct amrr_softc *asc = (struct amrr_softc *) sc->sc_rc;
462 struct ieee80211com *ic = &sc->sc_ic;
463 int interval;
464
465 if (ifp->if_flags & IFF_RUNNING) {
466 sc->sc_stats.ast_rate_calls++;
467
468 if (ic->ic_opmode == IEEE80211_M_STA)
469 ath_rate_ctl(sc, ic->ic_bss); /* NB: no reference */
470 else if (ic->ic_sta != NULL)
471 ieee80211_iterate_nodes(ic->ic_sta, ath_rate_ctl, sc);
472 }
473 interval = ath_rateinterval;
474 if (ic->ic_opmode == IEEE80211_M_STA)
475 interval /= 2;
476 callout_reset(&asc->timer, (interval * hz) / 1000,
477 ath_ratectl, &sc->sc_if);
478}
479
480static void
481ath_rate_sysctlattach(struct ath_softc *sc)
482{
483 struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev);
484 struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev);
485
486 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
487 "rate_interval", CTLFLAG_RW, &ath_rateinterval, 0,
488 "rate control: operation interval (ms)");
489 /* XXX bounds check values */
490 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
491 "max_sucess_threshold", CTLFLAG_RW,
492 &ath_rate_max_success_threshold, 0, "");
493 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
494 "min_sucess_threshold", CTLFLAG_RW,
495 &ath_rate_min_success_threshold, 0, "");
496}
497
498struct ath_ratectrl *
499ath_rate_attach(struct ath_softc *sc)
500{
501 struct amrr_softc *asc;
502
503 asc = malloc(sizeof(struct amrr_softc), M_DEVBUF, M_NOWAIT|M_ZERO);
504 if (asc == NULL)
505 return NULL;
506 asc->arc.arc_space = sizeof(struct amrr_node);
507 callout_init(&asc->timer, debug_mpsafenet ? CALLOUT_MPSAFE : 0);
508 ath_rate_sysctlattach(sc);
509
510 return &asc->arc;
511}
512
513void
514ath_rate_detach(struct ath_ratectrl *arc)
515{
516 struct amrr_softc *asc = (struct amrr_softc *) arc;
517
518 callout_drain(&asc->timer);
519 free(asc, M_DEVBUF);
520}
521
522/*
523 * Module glue.
524 */
525static int
526amrr_modevent(module_t mod, int type, void *unused)
527{
528 switch (type) {
529 case MOD_LOAD:
530 if (bootverbose)
531 printf("ath_rate: <AMRR rate control algorithm> version 0.1\n");
532 return 0;
533 case MOD_UNLOAD:
534 return 0;
535 }
536 return EINVAL;
537}
538
539static moduledata_t amrr_mod = {
540 "ath_rate",
541 amrr_modevent,
542 0
543};
544DECLARE_MODULE(ath_rate, amrr_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
545MODULE_VERSION(ath_rate, 1);
546MODULE_DEPEND(ath_rate, wlan, 1, 1, 1);
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