9  *   Copyright (C) 2005-2007 Derek Smithies <derek@indranet.co.nz>
26  *   3. Neither the names of the above-listed copyright holders nor the names
59 		_mi->sample_table[(_idx * SAMPLE_COLUMNS) + _col]
66 	for (i = rix; i >= 0; i--)  in rix_to_ndx()
67 		if (mi->r[i].rix == rix)  in rix_to_ndx()
77 	usecs = mr->perfect_tx_time;  in minstrel_get_tp_avg()
82 	if (mr->stats.prob_avg < MINSTREL_FRAC(10, 100))  in minstrel_get_tp_avg()
97 	struct minstrel_rate_stats *cur_mrs = &mi->r[i].stats;  in minstrel_sort_best_tp_rates()
99 	for (j = MAX_THR_RATES; j > 0; --j) {  in minstrel_sort_best_tp_rates()
100 		tmp_mrs = &mi->r[tp_list[j - 1]].stats;  in minstrel_sort_best_tp_rates()
101 		if (minstrel_get_tp_avg(&mi->r[i], cur_mrs->prob_avg) <=  in minstrel_sort_best_tp_rates()
102 		    minstrel_get_tp_avg(&mi->r[tp_list[j - 1]], tmp_mrs->prob_avg))  in minstrel_sort_best_tp_rates()
106 	if (j < MAX_THR_RATES - 1)  in minstrel_sort_best_tp_rates()
107 		memmove(&tp_list[j + 1], &tp_list[j], MAX_THR_RATES - (j + 1));  in minstrel_sort_best_tp_rates()
114 		  int offset, int idx)  in minstrel_set_rate()  argument
116 	struct minstrel_rate *r = &mi->r[idx];  in minstrel_set_rate()
118 	ratetbl->rate[offset].idx = r->rix;  in minstrel_set_rate()
119 	ratetbl->rate[offset].count = r->adjusted_retry_count;  in minstrel_set_rate()
120 	ratetbl->rate[offset].count_cts = r->retry_count_cts;  in minstrel_set_rate()
121 	ratetbl->rate[offset].count_rts = r->stats.retry_count_rtscts;  in minstrel_set_rate()
135 	minstrel_set_rate(mi, ratetbl, i++, mi->max_tp_rate[0]);  in minstrel_update_rates()
137 	if (mp->hw->max_rates >= 3) {  in minstrel_update_rates()
139 		minstrel_set_rate(mi, ratetbl, i++, mi->max_tp_rate[1]);  in minstrel_update_rates()
142 	if (mp->hw->max_rates >= 2) {  in minstrel_update_rates()
144 		minstrel_set_rate(mi, ratetbl, i++, mi->max_prob_rate);  in minstrel_update_rates()
148 	ratetbl->rate[i].idx = mi->lowest_rix;  in minstrel_update_rates()
149 	ratetbl->rate[i].count = mp->max_retry;  in minstrel_update_rates()
150 	ratetbl->rate[i].count_cts = mp->max_retry;  in minstrel_update_rates()
151 	ratetbl->rate[i].count_rts = mp->max_retry;  in minstrel_update_rates()
153 	rate_control_set_rates(mp->hw, mi->sta, ratetbl);  in minstrel_update_rates()
165 	if (unlikely(mrs->attempts > 0)) {  in minstrel_calc_rate_stats()
166 		mrs->sample_skipped = 0;  in minstrel_calc_rate_stats()
167 		cur_prob = MINSTREL_FRAC(mrs->success, mrs->attempts);  in minstrel_calc_rate_stats()
168 		if (mp->new_avg) {  in minstrel_calc_rate_stats()
169 			minstrel_filter_avg_add(&mrs->prob_avg,  in minstrel_calc_rate_stats()
170 						&mrs->prob_avg_1, cur_prob);  in minstrel_calc_rate_stats()
171 		} else if (unlikely(!mrs->att_hist)) {  in minstrel_calc_rate_stats()
172 			mrs->prob_avg = cur_prob;  in minstrel_calc_rate_stats()
175 			mrs->prob_avg = minstrel_ewma(mrs->prob_avg,  in minstrel_calc_rate_stats()
179 		mrs->att_hist += mrs->attempts;  in minstrel_calc_rate_stats()
180 		mrs->succ_hist += mrs->success;  in minstrel_calc_rate_stats()
182 		mrs->sample_skipped++;  in minstrel_calc_rate_stats()
185 	mrs->last_success = mrs->success;  in minstrel_calc_rate_stats()
186 	mrs->last_attempts = mrs->attempts;  in minstrel_calc_rate_stats()
187 	mrs->success = 0;  in minstrel_calc_rate_stats()
188 	mrs->attempts = 0;  in minstrel_calc_rate_stats()
201 	for (i = 0; i < mi->n_rates; i++) {  in minstrel_update_stats()
202 		struct minstrel_rate *mr = &mi->r[i];  in minstrel_update_stats()
203 		struct minstrel_rate_stats *mrs = &mi->r[i].stats;  in minstrel_update_stats()
204 		struct minstrel_rate_stats *tmp_mrs = &mi->r[tmp_prob_rate].stats;  in minstrel_update_stats()
211 		if (mrs->prob_avg > MINSTREL_FRAC(95, 100) ||  in minstrel_update_stats()
212 		    mrs->prob_avg < MINSTREL_FRAC(10, 100)) {  in minstrel_update_stats()
213 			mr->adjusted_retry_count = mrs->retry_count >> 1;  in minstrel_update_stats()
214 			if (mr->adjusted_retry_count > 2)  in minstrel_update_stats()
215 				mr->adjusted_retry_count = 2;  in minstrel_update_stats()
216 			mr->sample_limit = 4;  in minstrel_update_stats()
218 			mr->sample_limit = -1;  in minstrel_update_stats()
219 			mr->adjusted_retry_count = mrs->retry_count;  in minstrel_update_stats()
221 		if (!mr->adjusted_retry_count)  in minstrel_update_stats()
222 			mr->adjusted_retry_count = 2;  in minstrel_update_stats()
232 		if (mrs->prob_avg >= MINSTREL_FRAC(95, 100)) {  in minstrel_update_stats()
233 			tmp_cur_tp = minstrel_get_tp_avg(mr, mrs->prob_avg);  in minstrel_update_stats()
234 			tmp_prob_tp = minstrel_get_tp_avg(&mi->r[tmp_prob_rate],  in minstrel_update_stats()
235 							  tmp_mrs->prob_avg);  in minstrel_update_stats()
239 			if (mrs->prob_avg >= tmp_mrs->prob_avg)  in minstrel_update_stats()
245 	memcpy(mi->max_tp_rate, tmp_tp_rate, sizeof(mi->max_tp_rate));  in minstrel_update_stats()
246 	mi->max_prob_rate = tmp_prob_rate;  in minstrel_update_stats()
250 	if (mp->fixed_rate_idx != -1) {  in minstrel_update_stats()
251 		mi->max_tp_rate[0] = mp->fixed_rate_idx;  in minstrel_update_stats()
252 		mi->max_tp_rate[1] = mp->fixed_rate_idx;  in minstrel_update_stats()
253 		mi->max_prob_rate = mp->fixed_rate_idx;  in minstrel_update_stats()
258 	mi->last_stats_update = jiffies;  in minstrel_update_stats()
267 	struct ieee80211_tx_info *info = st->info;  in minstrel_tx_status()
270 	struct ieee80211_tx_rate *ar = info->status.rates;  in minstrel_tx_status()
274 	success = !!(info->flags & IEEE80211_TX_STAT_ACK);  in minstrel_tx_status()
284 		mi->r[ndx].stats.attempts += ar[i].count;  in minstrel_tx_status()
286 		if ((i != IEEE80211_TX_MAX_RATES - 1) && (ar[i + 1].idx < 0))  in minstrel_tx_status()
287 			mi->r[ndx].stats.success += success;  in minstrel_tx_status()
290 	if (time_after(jiffies, mi->last_stats_update +  in minstrel_tx_status()
291 				mp->update_interval / (mp->new_avg ? 2 : 1)))  in minstrel_tx_status()
300 	u8 retry = mr->adjusted_retry_count;  in minstrel_get_retry_count()
302 	if (info->control.use_rts)  in minstrel_get_retry_count()
303 		retry = max_t(u8, 2, min(mr->stats.retry_count_rtscts, retry));  in minstrel_get_retry_count()
304 	else if (info->control.use_cts_prot)  in minstrel_get_retry_count()
305 		retry = max_t(u8, 2, min(mr->retry_count_cts, retry));  in minstrel_get_retry_count()
314 	sample_ndx = SAMPLE_TBL(mi, mi->sample_row, mi->sample_column);  in minstrel_get_next_sample()
315 	mi->sample_row++;  in minstrel_get_next_sample()
316 	if ((int) mi->sample_row >= mi->n_rates) {  in minstrel_get_next_sample()
317 		mi->sample_row = 0;  in minstrel_get_next_sample()
318 		mi->sample_column++;  in minstrel_get_next_sample()
319 		if (mi->sample_column >= SAMPLE_COLUMNS)  in minstrel_get_next_sample()
320 			mi->sample_column = 0;  in minstrel_get_next_sample()
329 	struct sk_buff *skb = txrc->skb;  in minstrel_get_rate()
333 	struct ieee80211_tx_rate *rate = &info->control.rates[0];  in minstrel_get_rate()
341 	/* check multi-rate-retry capabilities & adjust lookaround_rate */  in minstrel_get_rate()
342 	mrr_capable = mp->has_mrr &&  in minstrel_get_rate()
343 		      !txrc->rts &&  in minstrel_get_rate()
344 		      !txrc->bss_conf->use_cts_prot;  in minstrel_get_rate()
346 		sampling_ratio = mp->lookaround_rate_mrr;  in minstrel_get_rate()
348 		sampling_ratio = mp->lookaround_rate;  in minstrel_get_rate()
351 	mi->total_packets++;  in minstrel_get_rate()
354 	if (mp->fixed_rate_idx != -1)  in minstrel_get_rate()
358 	/* Don't use EAPOL frames for sampling on non-mrr hw */  in minstrel_get_rate()
359 	if (mp->hw->max_rates == 1 &&  in minstrel_get_rate()
360 	    (info->control.flags & IEEE80211_TX_CTRL_PORT_CTRL_PROTO))  in minstrel_get_rate()
363 	delta = (mi->total_packets * sampling_ratio / 100) -  in minstrel_get_rate()
364 			mi->sample_packets;  in minstrel_get_rate()
367 	prev_sample = mi->prev_sample;  in minstrel_get_rate()
368 	mi->prev_sample = false;  in minstrel_get_rate()
372 	if (mi->total_packets >= 10000) {  in minstrel_get_rate()
373 		mi->sample_packets = 0;  in minstrel_get_rate()
374 		mi->total_packets = 0;  in minstrel_get_rate()
375 	} else if (delta > mi->n_rates * 2) {  in minstrel_get_rate()
376 		/* With multi-rate retry, not every planned sample  in minstrel_get_rate()
378 		 * chain is set up - [max_tp,sample,prob,lowest] for  in minstrel_get_rate()
385 		mi->sample_packets += (delta - mi->n_rates * 2);  in minstrel_get_rate()
390 	msr = &mi->r[ndx];  in minstrel_get_rate()
391 	mr = &mi->r[mi->max_tp_rate[0]];  in minstrel_get_rate()
397 	if (msr->perfect_tx_time < mr->perfect_tx_time ||  in minstrel_get_rate()
398 	    msr->stats.sample_skipped >= 20) {  in minstrel_get_rate()
399 		if (!msr->sample_limit)  in minstrel_get_rate()
402 		mi->sample_packets++;  in minstrel_get_rate()
403 		if (msr->sample_limit > 0)  in minstrel_get_rate()
404 			msr->sample_limit--;  in minstrel_get_rate()
411 	   (mi->r[ndx].stats.prob_avg > MINSTREL_FRAC(95, 100)))  in minstrel_get_rate()
414 	mi->prev_sample = true;  in minstrel_get_rate()
416 	rate->idx = mi->r[ndx].rix;  in minstrel_get_rate()
417 	rate->count = minstrel_get_retry_count(&mi->r[ndx], info);  in minstrel_get_rate()
418 	info->flags |= IEEE80211_TX_CTL_RATE_CTRL_PROBE;  in minstrel_get_rate()
428 	int erp = !!(rate->flags & IEEE80211_RATE_ERP_G);  in calc_rate_durations()
431 	d->perfect_tx_time = ieee80211_frame_duration(band, 1200,  in calc_rate_durations()
432 			DIV_ROUND_UP(rate->bitrate, 1 << shift), erp, 1,  in calc_rate_durations()
434 	d->ack_time = ieee80211_frame_duration(band, 10,  in calc_rate_durations()
435 			DIV_ROUND_UP(rate->bitrate, 1 << shift), erp, 1,  in calc_rate_durations()
442 	unsigned int i, col, new_idx;  in init_sample_table()  local
445 	mi->sample_column = 0;  in init_sample_table()
446 	mi->sample_row = 0;  in init_sample_table()
447 	memset(mi->sample_table, 0xff, SAMPLE_COLUMNS * mi->n_rates);  in init_sample_table()
449 	for (col = 0; col < SAMPLE_COLUMNS; col++) {  in init_sample_table()
451 		for (i = 0; i < mi->n_rates; i++) {  in init_sample_table()
452 			new_idx = (i + rnd[i & 7]) % mi->n_rates;  in init_sample_table()
453 			while (SAMPLE_TBL(mi, new_idx, col) != 0xff)  in init_sample_table()
454 				new_idx = (new_idx + 1) % mi->n_rates;  in init_sample_table()
456 			SAMPLE_TBL(mi, new_idx, col) = i;  in init_sample_table()
473 	mi->sta = sta;  in minstrel_rate_init()
474 	mi->lowest_rix = rate_lowest_index(sband, sta);  in minstrel_rate_init()
475 	ctl_rate = &sband->bitrates[mi->lowest_rix];  in minstrel_rate_init()
476 	mi->sp_ack_dur = ieee80211_frame_duration(sband->band, 10,  in minstrel_rate_init()
477 				ctl_rate->bitrate,  in minstrel_rate_init()
478 				!!(ctl_rate->flags & IEEE80211_RATE_ERP_G), 1,  in minstrel_rate_init()
481 	rate_flags = ieee80211_chandef_rate_flags(&mp->hw->conf.chandef);  in minstrel_rate_init()
482 	memset(mi->max_tp_rate, 0, sizeof(mi->max_tp_rate));  in minstrel_rate_init()
483 	mi->max_prob_rate = 0;  in minstrel_rate_init()
485 	for (i = 0; i < sband->n_bitrates; i++) {  in minstrel_rate_init()
486 		struct minstrel_rate *mr = &mi->r[n];  in minstrel_rate_init()
487 		struct minstrel_rate_stats *mrs = &mi->r[n].stats;  in minstrel_rate_init()
490 		unsigned int cw = mp->cw_min;  in minstrel_rate_init()
493 		if (!rate_supported(sta, sband->band, i))  in minstrel_rate_init()
495 		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)  in minstrel_rate_init()
502 		mr->rix = i;  in minstrel_rate_init()
504 		mr->bitrate = DIV_ROUND_UP(sband->bitrates[i].bitrate,  in minstrel_rate_init()
506 		calc_rate_durations(sband->band, mr, &sband->bitrates[i],  in minstrel_rate_init()
511 		mr->sample_limit = -1;  in minstrel_rate_init()
512 		mrs->retry_count = 1;  in minstrel_rate_init()
513 		mr->retry_count_cts = 1;  in minstrel_rate_init()
514 		mrs->retry_count_rtscts = 1;  in minstrel_rate_init()
515 		tx_time = mr->perfect_tx_time + mi->sp_ack_dur;  in minstrel_rate_init()
518 			tx_time_single = mr->ack_time + mr->perfect_tx_time;  in minstrel_rate_init()
522 			cw = min((cw << 1) | 1, mp->cw_max);  in minstrel_rate_init()
525 			tx_time_cts += tx_time_single + mi->sp_ack_dur;  in minstrel_rate_init()
526 			tx_time_rtscts += tx_time_single + 2 * mi->sp_ack_dur;  in minstrel_rate_init()
527 			if ((tx_time_cts < mp->segment_size) &&  in minstrel_rate_init()
528 				(mr->retry_count_cts < mp->max_retry))  in minstrel_rate_init()
529 				mr->retry_count_cts++;  in minstrel_rate_init()
530 			if ((tx_time_rtscts < mp->segment_size) &&  in minstrel_rate_init()
531 				(mrs->retry_count_rtscts < mp->max_retry))  in minstrel_rate_init()
532 				mrs->retry_count_rtscts++;  in minstrel_rate_init()
533 		} while ((tx_time < mp->segment_size) &&  in minstrel_rate_init()
534 				(++mr->stats.retry_count < mp->max_retry));  in minstrel_rate_init()
535 		mr->adjusted_retry_count = mrs->retry_count;  in minstrel_rate_init()
536 		if (!(sband->bitrates[i].flags & IEEE80211_RATE_ERP_G))  in minstrel_rate_init()
537 			mr->retry_count_cts = mrs->retry_count;  in minstrel_rate_init()
540 	for (i = n; i < sband->n_bitrates; i++) {  in minstrel_rate_init()
541 		struct minstrel_rate *mr = &mi->r[i];  in minstrel_rate_init()
542 		mr->rix = -1;  in minstrel_rate_init()
545 	mi->n_rates = n;  in minstrel_rate_init()
546 	mi->last_stats_update = jiffies;  in minstrel_rate_init()
556 	int idx = mi->max_tp_rate[0];  in minstrel_get_expected_throughput()
562 	tmp_mrs = &mi->r[idx].stats;  in minstrel_get_expected_throughput()
563 	tmp_cur_tp = minstrel_get_tp_avg(&mi->r[idx], tmp_mrs->prob_avg) * 10;  in minstrel_get_expected_throughput()