xref: /dflybsd-src/sys/dev/netif/ath/ath_rate/amrr/amrr.c (revision c97741cc22e42db25da3287dba6df2e6913de3a0)
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, MERCHANTIBILITY
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 
41 /*
42  * AMRR rate control. See:
43  * http://www-sop.inria.fr/rapports/sophia/RR-5208.html
44  * "IEEE 802.11 Rate Adaptation: A Practical Approach" by
45  *    Mathieu Lacage, Hossein Manshaei, Thierry Turletti
46  */
47 #include "opt_ath.h"
48 #include "opt_inet.h"
49 #include "opt_wlan.h"
50 
51 #include <sys/param.h>
52 #include <sys/systm.h>
53 #include <sys/sysctl.h>
54 #include <sys/kernel.h>
55 #include <sys/lock.h>
56 #include <sys/mutex.h>
57 #include <sys/errno.h>
58 #include <sys/bus.h>
59 #include <sys/socket.h>
60 
61 #include <net/if.h>
62 #include <net/if_media.h>
63 #include <net/if_arp.h>
64 
65 #include <netproto/802_11/ieee80211_var.h>
66 
67 #include <net/bpf.h>
68 
69 #ifdef INET
70 #include <netinet/in.h>
71 #include <netinet/if_ether.h>
72 #endif
73 
74 #include <dev/netif/ath/ath/if_athvar.h>
75 #include <dev/netif/ath/ath_rate/amrr/amrr.h>
76 #include <dev/netif/ath/ath_hal/ah_desc.h>
77 
78 static	int ath_rateinterval = 1000;		/* rate ctl interval (ms)  */
79 static	int ath_rate_max_success_threshold = 10;
80 static	int ath_rate_min_success_threshold = 1;
81 
82 static void	ath_rate_update(struct ath_softc *, struct ieee80211_node *,
83 			int rate);
84 static void	ath_rate_ctl_start(struct ath_softc *, struct ieee80211_node *);
85 static void	ath_rate_ctl(void *, struct ieee80211_node *);
86 
87 void
88 ath_rate_node_init(struct ath_softc *sc, struct ath_node *an)
89 {
90 	/* NB: assumed to be zero'd by caller */
91 }
92 
93 void
94 ath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an)
95 {
96 }
97 
98 void
99 ath_rate_findrate(struct ath_softc *sc, struct ath_node *an,
100 	int shortPreamble, size_t frameLen,
101 	u_int8_t *rix, int *try0, u_int8_t *txrate)
102 {
103 	struct amrr_node *amn = ATH_NODE_AMRR(an);
104 
105 	*rix = amn->amn_tx_rix0;
106 	*try0 = amn->amn_tx_try0;
107 	if (shortPreamble)
108 		*txrate = amn->amn_tx_rate0sp;
109 	else
110 		*txrate = amn->amn_tx_rate0;
111 }
112 
113 /*
114  * Get the TX rates.
115  *
116  * The short preamble bits aren't set here; the caller should augment
117  * the returned rate with the relevant preamble rate flag.
118  */
119 void
120 ath_rate_getxtxrates(struct ath_softc *sc, struct ath_node *an,
121     uint8_t rix0, struct ath_rc_series *rc)
122 {
123 	struct amrr_node *amn = ATH_NODE_AMRR(an);
124 
125 	rc[0].flags = rc[1].flags = rc[2].flags = rc[3].flags = 0;
126 
127 	rc[0].rix = amn->amn_tx_rate0;
128 	rc[1].rix = amn->amn_tx_rate1;
129 	rc[2].rix = amn->amn_tx_rate2;
130 	rc[3].rix = amn->amn_tx_rate3;
131 
132 	rc[0].tries = amn->amn_tx_try0;
133 	rc[1].tries = amn->amn_tx_try1;
134 	rc[2].tries = amn->amn_tx_try2;
135 	rc[3].tries = amn->amn_tx_try3;
136 }
137 
138 
139 void
140 ath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an,
141 	struct ath_desc *ds, int shortPreamble, u_int8_t rix)
142 {
143 	struct amrr_node *amn = ATH_NODE_AMRR(an);
144 
145 	ath_hal_setupxtxdesc(sc->sc_ah, ds
146 		, amn->amn_tx_rate1sp, amn->amn_tx_try1	/* series 1 */
147 		, amn->amn_tx_rate2sp, amn->amn_tx_try2	/* series 2 */
148 		, amn->amn_tx_rate3sp, amn->amn_tx_try3	/* series 3 */
149 	);
150 }
151 
152 void
153 ath_rate_tx_complete(struct ath_softc *sc, struct ath_node *an,
154 	const struct ath_rc_series *rc, const struct ath_tx_status *ts,
155 	int frame_size, int nframes, int nbad)
156 {
157 	struct amrr_node *amn = ATH_NODE_AMRR(an);
158 	int sr = ts->ts_shortretry;
159 	int lr = ts->ts_longretry;
160 	int retry_count = sr + lr;
161 
162 	amn->amn_tx_try0_cnt++;
163 	if (retry_count == 1) {
164 		amn->amn_tx_try1_cnt++;
165 	} else if (retry_count == 2) {
166 		amn->amn_tx_try1_cnt++;
167 		amn->amn_tx_try2_cnt++;
168 	} else if (retry_count == 3) {
169 		amn->amn_tx_try1_cnt++;
170 		amn->amn_tx_try2_cnt++;
171 		amn->amn_tx_try3_cnt++;
172 	} else if (retry_count > 3) {
173 		amn->amn_tx_try1_cnt++;
174 		amn->amn_tx_try2_cnt++;
175 		amn->amn_tx_try3_cnt++;
176 		amn->amn_tx_failure_cnt++;
177 	}
178 	if (amn->amn_interval != 0 &&
179 	    ticks - amn->amn_ticks > amn->amn_interval) {
180 		ath_rate_ctl(sc, &an->an_node);
181 		amn->amn_ticks = ticks;
182 	}
183 }
184 
185 void
186 ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew)
187 {
188 	if (isnew)
189 		ath_rate_ctl_start(sc, &an->an_node);
190 }
191 
192 static void
193 node_reset(struct amrr_node *amn)
194 {
195 	amn->amn_tx_try0_cnt = 0;
196 	amn->amn_tx_try1_cnt = 0;
197 	amn->amn_tx_try2_cnt = 0;
198 	amn->amn_tx_try3_cnt = 0;
199 	amn->amn_tx_failure_cnt = 0;
200   	amn->amn_success = 0;
201   	amn->amn_recovery = 0;
202   	amn->amn_success_threshold = ath_rate_min_success_threshold;
203 }
204 
205 
206 /**
207  * The code below assumes that we are dealing with hardware multi rate retry
208  * I have no idea what will happen if you try to use this module with another
209  * type of hardware. Your machine might catch fire or it might work with
210  * horrible performance...
211  */
212 static void
213 ath_rate_update(struct ath_softc *sc, struct ieee80211_node *ni, int rate)
214 {
215 	struct ath_node *an = ATH_NODE(ni);
216 	struct amrr_node *amn = ATH_NODE_AMRR(an);
217 	struct ieee80211vap *vap = ni->ni_vap;
218 	const HAL_RATE_TABLE *rt = sc->sc_currates;
219 	u_int8_t rix;
220 
221 	KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode));
222 
223 	IEEE80211_NOTE(vap, IEEE80211_MSG_RATECTL, ni,
224 	    "%s: set xmit rate to %dM", __func__,
225 	    ni->ni_rates.rs_nrates > 0 ?
226 		(ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL) / 2 : 0);
227 
228 	amn->amn_rix = rate;
229 	/*
230 	 * Before associating a node has no rate set setup
231 	 * so we can't calculate any transmit codes to use.
232 	 * This is ok since we should never be sending anything
233 	 * but management frames and those always go at the
234 	 * lowest hardware rate.
235 	 */
236 	if (ni->ni_rates.rs_nrates > 0) {
237 		ni->ni_txrate = ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL;
238 		amn->amn_tx_rix0 = sc->sc_rixmap[ni->ni_txrate];
239 		amn->amn_tx_rate0 = rt->info[amn->amn_tx_rix0].rateCode;
240 		amn->amn_tx_rate0sp = amn->amn_tx_rate0 |
241 			rt->info[amn->amn_tx_rix0].shortPreamble;
242 		if (sc->sc_mrretry) {
243 			amn->amn_tx_try0 = 1;
244 			amn->amn_tx_try1 = 1;
245 			amn->amn_tx_try2 = 1;
246 			amn->amn_tx_try3 = 1;
247 			if (--rate >= 0) {
248 				rix = sc->sc_rixmap[
249 						    ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL];
250 				amn->amn_tx_rate1 = rt->info[rix].rateCode;
251 				amn->amn_tx_rate1sp = amn->amn_tx_rate1 |
252 					rt->info[rix].shortPreamble;
253 			} else {
254 				amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0;
255 			}
256 			if (--rate >= 0) {
257 				rix = sc->sc_rixmap[
258 						    ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL];
259 				amn->amn_tx_rate2 = rt->info[rix].rateCode;
260 				amn->amn_tx_rate2sp = amn->amn_tx_rate2 |
261 					rt->info[rix].shortPreamble;
262 			} else {
263 				amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0;
264 			}
265 			if (rate > 0) {
266 				/* NB: only do this if we didn't already do it above */
267 				amn->amn_tx_rate3 = rt->info[0].rateCode;
268 				amn->amn_tx_rate3sp =
269 					amn->amn_tx_rate3 | rt->info[0].shortPreamble;
270 			} else {
271 				amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0;
272 			}
273 		} else {
274 			amn->amn_tx_try0 = ATH_TXMAXTRY;
275 			/* theorically, these statements are useless because
276 			 *  the code which uses them tests for an_tx_try0 == ATH_TXMAXTRY
277 			 */
278 			amn->amn_tx_try1 = 0;
279 			amn->amn_tx_try2 = 0;
280 			amn->amn_tx_try3 = 0;
281 			amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0;
282 			amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0;
283 			amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0;
284 		}
285 	}
286 	node_reset(amn);
287 
288 	amn->amn_interval = ath_rateinterval;
289 	if (vap->iv_opmode == IEEE80211_M_STA)
290 		amn->amn_interval /= 2;
291 	amn->amn_interval = (amn->amn_interval * hz) / 1000;
292 }
293 
294 /*
295  * Set the starting transmit rate for a node.
296  */
297 static void
298 ath_rate_ctl_start(struct ath_softc *sc, struct ieee80211_node *ni)
299 {
300 #define	RATE(_ix)	(ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL)
301 	const struct ieee80211_txparam *tp = ni->ni_txparms;
302 	int srate;
303 
304 	KASSERT(ni->ni_rates.rs_nrates > 0, ("no rates"));
305 	if (tp == NULL || tp->ucastrate == IEEE80211_FIXED_RATE_NONE) {
306 		/*
307 		 * No fixed rate is requested. For 11b start with
308 		 * the highest negotiated rate; otherwise, for 11g
309 		 * and 11a, we start "in the middle" at 24Mb or 36Mb.
310 		 */
311 		srate = ni->ni_rates.rs_nrates - 1;
312 		if (sc->sc_curmode != IEEE80211_MODE_11B) {
313 			/*
314 			 * Scan the negotiated rate set to find the
315 			 * closest rate.
316 			 */
317 			/* NB: the rate set is assumed sorted */
318 			for (; srate >= 0 && RATE(srate) > 72; srate--)
319 				;
320 		}
321 	} else {
322 		/*
323 		 * A fixed rate is to be used; ic_fixed_rate is the
324 		 * IEEE code for this rate (sans basic bit).  Convert this
325 		 * to the index into the negotiated rate set for
326 		 * the node.  We know the rate is there because the
327 		 * rate set is checked when the station associates.
328 		 */
329 		/* NB: the rate set is assumed sorted */
330 		srate = ni->ni_rates.rs_nrates - 1;
331 		for (; srate >= 0 && RATE(srate) != tp->ucastrate; srate--)
332 			;
333 	}
334 	/*
335 	 * The selected rate may not be available due to races
336 	 * and mode settings.  Also orphaned nodes created in
337 	 * adhoc mode may not have any rate set so this lookup
338 	 * can fail.  This is not fatal.
339 	 */
340 	ath_rate_update(sc, ni, srate < 0 ? 0 : srate);
341 #undef RATE
342 }
343 
344 /*
345  * Examine and potentially adjust the transmit rate.
346  */
347 static void
348 ath_rate_ctl(void *arg, struct ieee80211_node *ni)
349 {
350 	struct ath_softc *sc = arg;
351 	struct amrr_node *amn = ATH_NODE_AMRR(ATH_NODE (ni));
352 	int rix;
353 
354 #define is_success(amn) \
355 (amn->amn_tx_try1_cnt  < (amn->amn_tx_try0_cnt/10))
356 #define is_enough(amn) \
357 (amn->amn_tx_try0_cnt > 10)
358 #define is_failure(amn) \
359 (amn->amn_tx_try1_cnt > (amn->amn_tx_try0_cnt/3))
360 
361 	rix = amn->amn_rix;
362 
363   	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni,
364 	    "cnt0: %d cnt1: %d cnt2: %d cnt3: %d -- threshold: %d",
365 	    amn->amn_tx_try0_cnt, amn->amn_tx_try1_cnt, amn->amn_tx_try2_cnt,
366 	    amn->amn_tx_try3_cnt, amn->amn_success_threshold);
367   	if (is_success (amn) && is_enough (amn)) {
368 		amn->amn_success++;
369 		if (amn->amn_success == amn->amn_success_threshold &&
370 		    rix + 1 < ni->ni_rates.rs_nrates) {
371   			amn->amn_recovery = 1;
372   			amn->amn_success = 0;
373   			rix++;
374 			IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni,
375 			    "increase rate to %d", rix);
376   		} else {
377 			amn->amn_recovery = 0;
378 		}
379   	} else if (is_failure (amn)) {
380   		amn->amn_success = 0;
381 		if (rix > 0) {
382   			if (amn->amn_recovery) {
383   				/* recovery failure. */
384   				amn->amn_success_threshold *= 2;
385   				amn->amn_success_threshold = min (amn->amn_success_threshold,
386 								  (u_int)ath_rate_max_success_threshold);
387 				IEEE80211_NOTE(ni->ni_vap,
388 				    IEEE80211_MSG_RATECTL, ni,
389 				    "decrease rate recovery thr: %d",
390 				    amn->amn_success_threshold);
391   			} else {
392   				/* simple failure. */
393  				amn->amn_success_threshold = ath_rate_min_success_threshold;
394 				IEEE80211_NOTE(ni->ni_vap,
395 				    IEEE80211_MSG_RATECTL, ni,
396 				    "decrease rate normal thr: %d",
397 				    amn->amn_success_threshold);
398   			}
399 			amn->amn_recovery = 0;
400   			rix--;
401    		} else {
402 			amn->amn_recovery = 0;
403 		}
404 
405    	}
406 	if (is_enough (amn) || rix != amn->amn_rix) {
407 		/* reset counters. */
408 		amn->amn_tx_try0_cnt = 0;
409 		amn->amn_tx_try1_cnt = 0;
410 		amn->amn_tx_try2_cnt = 0;
411 		amn->amn_tx_try3_cnt = 0;
412 		amn->amn_tx_failure_cnt = 0;
413 	}
414 	if (rix != amn->amn_rix) {
415 		ath_rate_update(sc, ni, rix);
416 	}
417 }
418 
419 static int
420 ath_rate_fetch_node_stats(struct ath_softc *sc, struct ath_node *an,
421     struct ath_rateioctl *re)
422 {
423 
424 	return (EINVAL);
425 }
426 
427 static void
428 ath_rate_sysctlattach(struct ath_softc *sc)
429 {
430 	struct sysctl_ctx_list *ctx = &sc->sc_sysctl_ctx;
431 	struct sysctl_oid *tree = sc->sc_sysctl_tree;
432 
433 	SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
434 		"rate_interval", CTLFLAG_RW, &ath_rateinterval, 0,
435 		"rate control: operation interval (ms)");
436 	/* XXX bounds check values */
437 	SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
438 		"max_sucess_threshold", CTLFLAG_RW,
439 		&ath_rate_max_success_threshold, 0, "");
440 	SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
441 		"min_sucess_threshold", CTLFLAG_RW,
442 		&ath_rate_min_success_threshold, 0, "");
443 }
444 
445 struct ath_ratectrl *
446 ath_rate_attach(struct ath_softc *sc)
447 {
448 	struct amrr_softc *asc;
449 
450 	asc = kmalloc(sizeof(struct amrr_softc), M_DEVBUF, M_INTWAIT|M_ZERO);
451 	if (asc == NULL)
452 		return NULL;
453 	asc->arc.arc_space = sizeof(struct amrr_node);
454 	ath_rate_sysctlattach(sc);
455 
456 	return &asc->arc;
457 }
458 
459 void
460 ath_rate_detach(struct ath_ratectrl *arc)
461 {
462 	struct amrr_softc *asc = (struct amrr_softc *) arc;
463 
464 	kfree(asc, M_DEVBUF);
465 }
466 
467 /*
468  * Module glue.
469  */
470 static int
471 amrr_modevent(module_t mod, int type, void *unused)
472 {
473 	int error;
474 
475 	wlan_serialize_enter();
476 
477 	switch (type) {
478 	case MOD_LOAD:
479 		if (bootverbose) {
480 			kprintf("ath_rate: <AMRR rate control "
481 				"algorithm> version 0.1\n");
482 		}
483 		error = 0;
484 		break;
485 	case MOD_UNLOAD:
486 		error = 0;
487 		break;
488 	default:
489 		error = EINVAL;
490 		break;
491 	}
492 	wlan_serialize_exit();
493 
494 	return error;
495 }
496 
497 static moduledata_t amrr_mod = {
498         "ath_rate",
499 	amrr_modevent,
500 	0
501 };
502 
503 DECLARE_MODULE(ath_rate, amrr_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
504 MODULE_VERSION(ath_rate, 1);
505 MODULE_DEPEND(ath_rate, ath_hal, 1, 1, 1);
506 MODULE_DEPEND(ath_rate, wlan, 1, 1, 1);
507