2 * Copyright (c) 2004 INRIA
3 * Copyright (c) 2002-2005 Sam Leffler, Errno Consulting
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
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.
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.
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, MERCHANTIBILITY
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29 * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
30 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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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.
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
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
52 #include <sys/param.h>
53 #include <sys/systm.h>
54 #include <sys/sysctl.h>
55 #include <sys/kernel.h>
57 #include <sys/mutex.h>
58 #include <sys/errno.h>
62 #include <sys/socket.h>
65 #include <net/if_media.h>
66 #include <net/if_arp.h>
68 #include <netproto/802_11/ieee80211_var.h>
73 #include <netinet/in.h>
74 #include <netinet/if_ether.h>
77 #include <dev/netif/ath/ath/if_athvar.h>
78 #include <dev/netif/ath/ath_rate/amrr/amrr.h>
79 #include <dev/netif/ath/ath_hal/ah_desc.h>
81 static int ath_rateinterval = 1000; /* rate ctl interval (ms) */
82 static int ath_rate_max_success_threshold = 10;
83 static int ath_rate_min_success_threshold = 1;
85 static void ath_rate_update(struct ath_softc *, struct ieee80211_node *,
87 static void ath_rate_ctl_start(struct ath_softc *, struct ieee80211_node *);
88 static void ath_rate_ctl(void *, struct ieee80211_node *);
91 ath_rate_node_init(struct ath_softc *sc, struct ath_node *an)
93 /* NB: assumed to be zero'd by caller */
97 ath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an)
102 ath_rate_findrate(struct ath_softc *sc, struct ath_node *an,
103 int shortPreamble, size_t frameLen,
104 u_int8_t *rix, int *try0, u_int8_t *txrate)
106 struct amrr_node *amn = ATH_NODE_AMRR(an);
108 *rix = amn->amn_tx_rix0;
109 *try0 = amn->amn_tx_try0;
111 *txrate = amn->amn_tx_rate0sp;
113 *txrate = amn->amn_tx_rate0;
119 * The short preamble bits aren't set here; the caller should augment
120 * the returned rate with the relevant preamble rate flag.
123 ath_rate_getxtxrates(struct ath_softc *sc, struct ath_node *an,
124 uint8_t rix0, struct ath_rc_series *rc)
126 struct amrr_node *amn = ATH_NODE_AMRR(an);
128 rc[0].flags = rc[1].flags = rc[2].flags = rc[3].flags = 0;
130 rc[0].rix = amn->amn_tx_rate0;
131 rc[1].rix = amn->amn_tx_rate1;
132 rc[2].rix = amn->amn_tx_rate2;
133 rc[3].rix = amn->amn_tx_rate3;
135 rc[0].tries = amn->amn_tx_try0;
136 rc[1].tries = amn->amn_tx_try1;
137 rc[2].tries = amn->amn_tx_try2;
138 rc[3].tries = amn->amn_tx_try3;
143 ath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an,
144 struct ath_desc *ds, int shortPreamble, u_int8_t rix)
146 struct amrr_node *amn = ATH_NODE_AMRR(an);
148 ath_hal_setupxtxdesc(sc->sc_ah, ds
149 , amn->amn_tx_rate1sp, amn->amn_tx_try1 /* series 1 */
150 , amn->amn_tx_rate2sp, amn->amn_tx_try2 /* series 2 */
151 , amn->amn_tx_rate3sp, amn->amn_tx_try3 /* series 3 */
156 ath_rate_tx_complete(struct ath_softc *sc, struct ath_node *an,
157 const struct ath_rc_series *rc, const struct ath_tx_status *ts,
158 int frame_size, int nframes, int nbad)
160 struct amrr_node *amn = ATH_NODE_AMRR(an);
161 int sr = ts->ts_shortretry;
162 int lr = ts->ts_longretry;
163 int retry_count = sr + lr;
165 amn->amn_tx_try0_cnt++;
166 if (retry_count == 1) {
167 amn->amn_tx_try1_cnt++;
168 } else if (retry_count == 2) {
169 amn->amn_tx_try1_cnt++;
170 amn->amn_tx_try2_cnt++;
171 } else if (retry_count == 3) {
172 amn->amn_tx_try1_cnt++;
173 amn->amn_tx_try2_cnt++;
174 amn->amn_tx_try3_cnt++;
175 } else if (retry_count > 3) {
176 amn->amn_tx_try1_cnt++;
177 amn->amn_tx_try2_cnt++;
178 amn->amn_tx_try3_cnt++;
179 amn->amn_tx_failure_cnt++;
181 if (amn->amn_interval != 0 &&
182 ticks - amn->amn_ticks > amn->amn_interval) {
183 ath_rate_ctl(sc, &an->an_node);
184 amn->amn_ticks = ticks;
189 ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew)
192 ath_rate_ctl_start(sc, &an->an_node);
196 node_reset(struct amrr_node *amn)
198 amn->amn_tx_try0_cnt = 0;
199 amn->amn_tx_try1_cnt = 0;
200 amn->amn_tx_try2_cnt = 0;
201 amn->amn_tx_try3_cnt = 0;
202 amn->amn_tx_failure_cnt = 0;
203 amn->amn_success = 0;
204 amn->amn_recovery = 0;
205 amn->amn_success_threshold = ath_rate_min_success_threshold;
210 * The code below assumes that we are dealing with hardware multi rate retry
211 * I have no idea what will happen if you try to use this module with another
212 * type of hardware. Your machine might catch fire or it might work with
213 * horrible performance...
216 ath_rate_update(struct ath_softc *sc, struct ieee80211_node *ni, int rate)
218 struct ath_node *an = ATH_NODE(ni);
219 struct amrr_node *amn = ATH_NODE_AMRR(an);
220 struct ieee80211vap *vap = ni->ni_vap;
221 const HAL_RATE_TABLE *rt = sc->sc_currates;
224 KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode));
226 IEEE80211_NOTE(vap, IEEE80211_MSG_RATECTL, ni,
227 "%s: set xmit rate to %dM", __func__,
228 ni->ni_rates.rs_nrates > 0 ?
229 (ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL) / 2 : 0);
233 * Before associating a node has no rate set setup
234 * so we can't calculate any transmit codes to use.
235 * This is ok since we should never be sending anything
236 * but management frames and those always go at the
237 * lowest hardware rate.
239 if (ni->ni_rates.rs_nrates > 0) {
240 ni->ni_txrate = ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL;
241 amn->amn_tx_rix0 = sc->sc_rixmap[ni->ni_txrate];
242 amn->amn_tx_rate0 = rt->info[amn->amn_tx_rix0].rateCode;
243 amn->amn_tx_rate0sp = amn->amn_tx_rate0 |
244 rt->info[amn->amn_tx_rix0].shortPreamble;
245 if (sc->sc_mrretry) {
246 amn->amn_tx_try0 = 1;
247 amn->amn_tx_try1 = 1;
248 amn->amn_tx_try2 = 1;
249 amn->amn_tx_try3 = 1;
252 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL];
253 amn->amn_tx_rate1 = rt->info[rix].rateCode;
254 amn->amn_tx_rate1sp = amn->amn_tx_rate1 |
255 rt->info[rix].shortPreamble;
257 amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0;
261 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL];
262 amn->amn_tx_rate2 = rt->info[rix].rateCode;
263 amn->amn_tx_rate2sp = amn->amn_tx_rate2 |
264 rt->info[rix].shortPreamble;
266 amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0;
269 /* NB: only do this if we didn't already do it above */
270 amn->amn_tx_rate3 = rt->info[0].rateCode;
271 amn->amn_tx_rate3sp =
272 amn->amn_tx_rate3 | rt->info[0].shortPreamble;
274 amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0;
277 amn->amn_tx_try0 = ATH_TXMAXTRY;
278 /* theorically, these statements are useless because
279 * the code which uses them tests for an_tx_try0 == ATH_TXMAXTRY
281 amn->amn_tx_try1 = 0;
282 amn->amn_tx_try2 = 0;
283 amn->amn_tx_try3 = 0;
284 amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0;
285 amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0;
286 amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0;
291 amn->amn_interval = ath_rateinterval;
292 if (vap->iv_opmode == IEEE80211_M_STA)
293 amn->amn_interval /= 2;
294 amn->amn_interval = (amn->amn_interval * hz) / 1000;
298 * Set the starting transmit rate for a node.
301 ath_rate_ctl_start(struct ath_softc *sc, struct ieee80211_node *ni)
303 #define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL)
304 const struct ieee80211_txparam *tp = ni->ni_txparms;
307 KASSERT(ni->ni_rates.rs_nrates > 0, ("no rates"));
308 if (tp == NULL || tp->ucastrate == IEEE80211_FIXED_RATE_NONE) {
310 * No fixed rate is requested. For 11b start with
311 * the highest negotiated rate; otherwise, for 11g
312 * and 11a, we start "in the middle" at 24Mb or 36Mb.
314 srate = ni->ni_rates.rs_nrates - 1;
315 if (sc->sc_curmode != IEEE80211_MODE_11B) {
317 * Scan the negotiated rate set to find the
320 /* NB: the rate set is assumed sorted */
321 for (; srate >= 0 && RATE(srate) > 72; srate--)
326 * A fixed rate is to be used; ic_fixed_rate is the
327 * IEEE code for this rate (sans basic bit). Convert this
328 * to the index into the negotiated rate set for
329 * the node. We know the rate is there because the
330 * rate set is checked when the station associates.
332 /* NB: the rate set is assumed sorted */
333 srate = ni->ni_rates.rs_nrates - 1;
334 for (; srate >= 0 && RATE(srate) != tp->ucastrate; srate--)
338 * The selected rate may not be available due to races
339 * and mode settings. Also orphaned nodes created in
340 * adhoc mode may not have any rate set so this lookup
341 * can fail. This is not fatal.
343 ath_rate_update(sc, ni, srate < 0 ? 0 : srate);
348 * Examine and potentially adjust the transmit rate.
351 ath_rate_ctl(void *arg, struct ieee80211_node *ni)
353 struct ath_softc *sc = arg;
354 struct amrr_node *amn = ATH_NODE_AMRR(ATH_NODE (ni));
357 #define is_success(amn) \
358 (amn->amn_tx_try1_cnt < (amn->amn_tx_try0_cnt/10))
359 #define is_enough(amn) \
360 (amn->amn_tx_try0_cnt > 10)
361 #define is_failure(amn) \
362 (amn->amn_tx_try1_cnt > (amn->amn_tx_try0_cnt/3))
366 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni,
367 "cnt0: %d cnt1: %d cnt2: %d cnt3: %d -- threshold: %d",
368 amn->amn_tx_try0_cnt, amn->amn_tx_try1_cnt, amn->amn_tx_try2_cnt,
369 amn->amn_tx_try3_cnt, amn->amn_success_threshold);
370 if (is_success (amn) && is_enough (amn)) {
372 if (amn->amn_success == amn->amn_success_threshold &&
373 rix + 1 < ni->ni_rates.rs_nrates) {
374 amn->amn_recovery = 1;
375 amn->amn_success = 0;
377 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni,
378 "increase rate to %d", rix);
380 amn->amn_recovery = 0;
382 } else if (is_failure (amn)) {
383 amn->amn_success = 0;
385 if (amn->amn_recovery) {
386 /* recovery failure. */
387 amn->amn_success_threshold *= 2;
388 amn->amn_success_threshold = min (amn->amn_success_threshold,
389 (u_int)ath_rate_max_success_threshold);
390 IEEE80211_NOTE(ni->ni_vap,
391 IEEE80211_MSG_RATECTL, ni,
392 "decrease rate recovery thr: %d",
393 amn->amn_success_threshold);
395 /* simple failure. */
396 amn->amn_success_threshold = ath_rate_min_success_threshold;
397 IEEE80211_NOTE(ni->ni_vap,
398 IEEE80211_MSG_RATECTL, ni,
399 "decrease rate normal thr: %d",
400 amn->amn_success_threshold);
402 amn->amn_recovery = 0;
405 amn->amn_recovery = 0;
409 if (is_enough (amn) || rix != amn->amn_rix) {
410 /* reset counters. */
411 amn->amn_tx_try0_cnt = 0;
412 amn->amn_tx_try1_cnt = 0;
413 amn->amn_tx_try2_cnt = 0;
414 amn->amn_tx_try3_cnt = 0;
415 amn->amn_tx_failure_cnt = 0;
417 if (rix != amn->amn_rix) {
418 ath_rate_update(sc, ni, rix);
423 ath_rate_fetch_node_stats(struct ath_softc *sc, struct ath_node *an,
424 struct ath_rateioctl *re)
431 ath_rate_sysctlattach(struct ath_softc *sc)
433 struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev);
434 struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev);
436 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
437 "rate_interval", CTLFLAG_RW, &ath_rateinterval, 0,
438 "rate control: operation interval (ms)");
439 /* XXX bounds check values */
440 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
441 "max_sucess_threshold", CTLFLAG_RW,
442 &ath_rate_max_success_threshold, 0, "");
443 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
444 "min_sucess_threshold", CTLFLAG_RW,
445 &ath_rate_min_success_threshold, 0, "");
448 struct ath_ratectrl *
449 ath_rate_attach(struct ath_softc *sc)
451 struct amrr_softc *asc;
453 asc = kmalloc(sizeof(struct amrr_softc), M_DEVBUF, M_INTWAIT|M_ZERO);
456 asc->arc.arc_space = sizeof(struct amrr_node);
457 ath_rate_sysctlattach(sc);
463 ath_rate_detach(struct ath_ratectrl *arc)
465 struct amrr_softc *asc = (struct amrr_softc *) arc;
467 kfree(asc, M_DEVBUF);
474 amrr_modevent(module_t mod, int type, void *unused)
478 wlan_serialize_enter();
483 kprintf("ath_rate: <AMRR rate control "
484 "algorithm> version 0.1\n");
495 wlan_serialize_exit();
500 static moduledata_t amrr_mod = {
506 DECLARE_MODULE(ath_rate, amrr_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
507 MODULE_VERSION(ath_rate, 1);
508 MODULE_DEPEND(ath_rate, ath_hal, 1, 1, 1);
509 MODULE_DEPEND(ath_rate, wlan, 1, 1, 1);