Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2010 Felix Fietkau <nbd@openwrt.org> |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU General Public License version 2 as |
| 6 | * published by the Free Software Foundation. |
| 7 | */ |
| 8 | #include <linux/netdevice.h> |
| 9 | #include <linux/types.h> |
| 10 | #include <linux/skbuff.h> |
| 11 | #include <linux/debugfs.h> |
| 12 | #include <linux/random.h> |
| 13 | #include <linux/ieee80211.h> |
| 14 | #include <net/mac80211.h> |
| 15 | #include "rate.h" |
| 16 | #include "rc80211_minstrel.h" |
| 17 | #include "rc80211_minstrel_ht.h" |
| 18 | |
| 19 | #define AVG_PKT_SIZE 1200 |
| 20 | #define SAMPLE_COLUMNS 10 |
| 21 | #define EWMA_LEVEL 75 |
| 22 | |
| 23 | /* Number of bits for an average sized packet */ |
| 24 | #define MCS_NBITS (AVG_PKT_SIZE << 3) |
| 25 | |
| 26 | /* Number of symbols for a packet with (bps) bits per symbol */ |
| 27 | #define MCS_NSYMS(bps) ((MCS_NBITS + (bps) - 1) / (bps)) |
| 28 | |
| 29 | /* Transmission time for a packet containing (syms) symbols */ |
| 30 | #define MCS_SYMBOL_TIME(sgi, syms) \ |
| 31 | (sgi ? \ |
| 32 | ((syms) * 18 + 4) / 5 : /* syms * 3.6 us */ \ |
| 33 | (syms) << 2 /* syms * 4 us */ \ |
| 34 | ) |
| 35 | |
| 36 | /* Transmit duration for the raw data part of an average sized packet */ |
| 37 | #define MCS_DURATION(streams, sgi, bps) MCS_SYMBOL_TIME(sgi, MCS_NSYMS((streams) * (bps))) |
| 38 | |
Helmut Schaa | a5f69d94 | 2011-11-14 15:28:20 +0100 | [diff] [blame] | 39 | /* |
| 40 | * Define group sort order: HT40 -> SGI -> #streams |
| 41 | */ |
| 42 | #define GROUP_IDX(_streams, _sgi, _ht40) \ |
| 43 | MINSTREL_MAX_STREAMS * 2 * _ht40 + \ |
| 44 | MINSTREL_MAX_STREAMS * _sgi + \ |
| 45 | _streams - 1 |
| 46 | |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 47 | /* MCS rate information for an MCS group */ |
Helmut Schaa | a5f69d94 | 2011-11-14 15:28:20 +0100 | [diff] [blame] | 48 | #define MCS_GROUP(_streams, _sgi, _ht40) \ |
| 49 | [GROUP_IDX(_streams, _sgi, _ht40)] = { \ |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 50 | .streams = _streams, \ |
| 51 | .flags = \ |
| 52 | (_sgi ? IEEE80211_TX_RC_SHORT_GI : 0) | \ |
| 53 | (_ht40 ? IEEE80211_TX_RC_40_MHZ_WIDTH : 0), \ |
| 54 | .duration = { \ |
| 55 | MCS_DURATION(_streams, _sgi, _ht40 ? 54 : 26), \ |
| 56 | MCS_DURATION(_streams, _sgi, _ht40 ? 108 : 52), \ |
| 57 | MCS_DURATION(_streams, _sgi, _ht40 ? 162 : 78), \ |
| 58 | MCS_DURATION(_streams, _sgi, _ht40 ? 216 : 104), \ |
| 59 | MCS_DURATION(_streams, _sgi, _ht40 ? 324 : 156), \ |
| 60 | MCS_DURATION(_streams, _sgi, _ht40 ? 432 : 208), \ |
| 61 | MCS_DURATION(_streams, _sgi, _ht40 ? 486 : 234), \ |
| 62 | MCS_DURATION(_streams, _sgi, _ht40 ? 540 : 260) \ |
| 63 | } \ |
| 64 | } |
| 65 | |
| 66 | /* |
| 67 | * To enable sufficiently targeted rate sampling, MCS rates are divided into |
| 68 | * groups, based on the number of streams and flags (HT40, SGI) that they |
| 69 | * use. |
Helmut Schaa | a5f69d94 | 2011-11-14 15:28:20 +0100 | [diff] [blame] | 70 | * |
| 71 | * Sortorder has to be fixed for GROUP_IDX macro to be applicable: |
| 72 | * HT40 -> SGI -> #streams |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 73 | */ |
| 74 | const struct mcs_group minstrel_mcs_groups[] = { |
| 75 | MCS_GROUP(1, 0, 0), |
| 76 | MCS_GROUP(2, 0, 0), |
| 77 | #if MINSTREL_MAX_STREAMS >= 3 |
| 78 | MCS_GROUP(3, 0, 0), |
| 79 | #endif |
| 80 | |
| 81 | MCS_GROUP(1, 1, 0), |
| 82 | MCS_GROUP(2, 1, 0), |
| 83 | #if MINSTREL_MAX_STREAMS >= 3 |
| 84 | MCS_GROUP(3, 1, 0), |
| 85 | #endif |
| 86 | |
| 87 | MCS_GROUP(1, 0, 1), |
| 88 | MCS_GROUP(2, 0, 1), |
| 89 | #if MINSTREL_MAX_STREAMS >= 3 |
| 90 | MCS_GROUP(3, 0, 1), |
| 91 | #endif |
| 92 | |
| 93 | MCS_GROUP(1, 1, 1), |
| 94 | MCS_GROUP(2, 1, 1), |
| 95 | #if MINSTREL_MAX_STREAMS >= 3 |
| 96 | MCS_GROUP(3, 1, 1), |
| 97 | #endif |
| 98 | }; |
| 99 | |
| 100 | static u8 sample_table[SAMPLE_COLUMNS][MCS_GROUP_RATES]; |
| 101 | |
| 102 | /* |
| 103 | * Perform EWMA (Exponentially Weighted Moving Average) calculation |
| 104 | */ |
| 105 | static int |
| 106 | minstrel_ewma(int old, int new, int weight) |
| 107 | { |
| 108 | return (new * (100 - weight) + old * weight) / 100; |
| 109 | } |
| 110 | |
| 111 | /* |
| 112 | * Look up an MCS group index based on mac80211 rate information |
| 113 | */ |
| 114 | static int |
| 115 | minstrel_ht_get_group_idx(struct ieee80211_tx_rate *rate) |
| 116 | { |
Helmut Schaa | a5f69d94 | 2011-11-14 15:28:20 +0100 | [diff] [blame] | 117 | return GROUP_IDX((rate->idx / MCS_GROUP_RATES) + 1, |
| 118 | !!(rate->flags & IEEE80211_TX_RC_SHORT_GI), |
| 119 | !!(rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH)); |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 120 | } |
| 121 | |
| 122 | static inline struct minstrel_rate_stats * |
| 123 | minstrel_get_ratestats(struct minstrel_ht_sta *mi, int index) |
| 124 | { |
| 125 | return &mi->groups[index / MCS_GROUP_RATES].rates[index % MCS_GROUP_RATES]; |
| 126 | } |
| 127 | |
| 128 | |
| 129 | /* |
| 130 | * Recalculate success probabilities and counters for a rate using EWMA |
| 131 | */ |
| 132 | static void |
Patrick Kelle | 6048d763 | 2011-11-15 16:44:48 +0100 | [diff] [blame] | 133 | minstrel_calc_rate_ewma(struct minstrel_rate_stats *mr) |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 134 | { |
| 135 | if (unlikely(mr->attempts > 0)) { |
| 136 | mr->sample_skipped = 0; |
| 137 | mr->cur_prob = MINSTREL_FRAC(mr->success, mr->attempts); |
| 138 | if (!mr->att_hist) |
| 139 | mr->probability = mr->cur_prob; |
| 140 | else |
| 141 | mr->probability = minstrel_ewma(mr->probability, |
| 142 | mr->cur_prob, EWMA_LEVEL); |
| 143 | mr->att_hist += mr->attempts; |
| 144 | mr->succ_hist += mr->success; |
| 145 | } else { |
| 146 | mr->sample_skipped++; |
| 147 | } |
| 148 | mr->last_success = mr->success; |
| 149 | mr->last_attempts = mr->attempts; |
| 150 | mr->success = 0; |
| 151 | mr->attempts = 0; |
| 152 | } |
| 153 | |
| 154 | /* |
| 155 | * Calculate throughput based on the average A-MPDU length, taking into account |
| 156 | * the expected number of retransmissions and their expected length |
| 157 | */ |
| 158 | static void |
Patrick Kelle | 6048d763 | 2011-11-15 16:44:48 +0100 | [diff] [blame] | 159 | minstrel_ht_calc_tp(struct minstrel_ht_sta *mi, int group, int rate) |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 160 | { |
| 161 | struct minstrel_rate_stats *mr; |
| 162 | unsigned int usecs; |
| 163 | |
| 164 | mr = &mi->groups[group].rates[rate]; |
| 165 | |
| 166 | if (mr->probability < MINSTREL_FRAC(1, 10)) { |
| 167 | mr->cur_tp = 0; |
| 168 | return; |
| 169 | } |
| 170 | |
| 171 | usecs = mi->overhead / MINSTREL_TRUNC(mi->avg_ampdu_len); |
| 172 | usecs += minstrel_mcs_groups[group].duration[rate]; |
| 173 | mr->cur_tp = MINSTREL_TRUNC((1000000 / usecs) * mr->probability); |
| 174 | } |
| 175 | |
| 176 | /* |
| 177 | * Update rate statistics and select new primary rates |
| 178 | * |
| 179 | * Rules for rate selection: |
| 180 | * - max_prob_rate must use only one stream, as a tradeoff between delivery |
| 181 | * probability and throughput during strong fluctuations |
| 182 | * - as long as the max prob rate has a probability of more than 3/4, pick |
| 183 | * higher throughput rates, even if the probablity is a bit lower |
| 184 | */ |
| 185 | static void |
| 186 | minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi) |
| 187 | { |
| 188 | struct minstrel_mcs_group_data *mg; |
| 189 | struct minstrel_rate_stats *mr; |
| 190 | int cur_prob, cur_prob_tp, cur_tp, cur_tp2; |
| 191 | int group, i, index; |
| 192 | |
| 193 | if (mi->ampdu_packets > 0) { |
| 194 | mi->avg_ampdu_len = minstrel_ewma(mi->avg_ampdu_len, |
| 195 | MINSTREL_FRAC(mi->ampdu_len, mi->ampdu_packets), EWMA_LEVEL); |
| 196 | mi->ampdu_len = 0; |
| 197 | mi->ampdu_packets = 0; |
| 198 | } |
| 199 | |
| 200 | mi->sample_slow = 0; |
| 201 | mi->sample_count = 0; |
| 202 | mi->max_tp_rate = 0; |
| 203 | mi->max_tp_rate2 = 0; |
| 204 | mi->max_prob_rate = 0; |
| 205 | |
| 206 | for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) { |
| 207 | cur_prob = 0; |
| 208 | cur_prob_tp = 0; |
| 209 | cur_tp = 0; |
| 210 | cur_tp2 = 0; |
| 211 | |
| 212 | mg = &mi->groups[group]; |
| 213 | if (!mg->supported) |
| 214 | continue; |
| 215 | |
| 216 | mg->max_tp_rate = 0; |
| 217 | mg->max_tp_rate2 = 0; |
| 218 | mg->max_prob_rate = 0; |
| 219 | mi->sample_count++; |
| 220 | |
| 221 | for (i = 0; i < MCS_GROUP_RATES; i++) { |
| 222 | if (!(mg->supported & BIT(i))) |
| 223 | continue; |
| 224 | |
| 225 | mr = &mg->rates[i]; |
| 226 | mr->retry_updated = false; |
| 227 | index = MCS_GROUP_RATES * group + i; |
Patrick Kelle | 6048d763 | 2011-11-15 16:44:48 +0100 | [diff] [blame] | 228 | minstrel_calc_rate_ewma(mr); |
| 229 | minstrel_ht_calc_tp(mi, group, i); |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 230 | |
| 231 | if (!mr->cur_tp) |
| 232 | continue; |
| 233 | |
| 234 | /* ignore the lowest rate of each single-stream group */ |
| 235 | if (!i && minstrel_mcs_groups[group].streams == 1) |
| 236 | continue; |
| 237 | |
| 238 | if ((mr->cur_tp > cur_prob_tp && mr->probability > |
| 239 | MINSTREL_FRAC(3, 4)) || mr->probability > cur_prob) { |
| 240 | mg->max_prob_rate = index; |
| 241 | cur_prob = mr->probability; |
Ming Lei | 009271f | 2010-07-01 23:18:42 +0800 | [diff] [blame] | 242 | cur_prob_tp = mr->cur_tp; |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 243 | } |
| 244 | |
| 245 | if (mr->cur_tp > cur_tp) { |
| 246 | swap(index, mg->max_tp_rate); |
| 247 | cur_tp = mr->cur_tp; |
| 248 | mr = minstrel_get_ratestats(mi, index); |
| 249 | } |
| 250 | |
| 251 | if (index >= mg->max_tp_rate) |
| 252 | continue; |
| 253 | |
| 254 | if (mr->cur_tp > cur_tp2) { |
| 255 | mg->max_tp_rate2 = index; |
| 256 | cur_tp2 = mr->cur_tp; |
| 257 | } |
| 258 | } |
| 259 | } |
| 260 | |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 261 | /* try to sample up to half of the available rates during each interval */ |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 262 | mi->sample_count *= 4; |
| 263 | |
| 264 | cur_prob = 0; |
| 265 | cur_prob_tp = 0; |
| 266 | cur_tp = 0; |
| 267 | cur_tp2 = 0; |
| 268 | for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) { |
| 269 | mg = &mi->groups[group]; |
| 270 | if (!mg->supported) |
| 271 | continue; |
| 272 | |
| 273 | mr = minstrel_get_ratestats(mi, mg->max_prob_rate); |
| 274 | if (cur_prob_tp < mr->cur_tp && |
| 275 | minstrel_mcs_groups[group].streams == 1) { |
| 276 | mi->max_prob_rate = mg->max_prob_rate; |
| 277 | cur_prob = mr->cur_prob; |
Ming Lei | 009271f | 2010-07-01 23:18:42 +0800 | [diff] [blame] | 278 | cur_prob_tp = mr->cur_tp; |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 279 | } |
| 280 | |
| 281 | mr = minstrel_get_ratestats(mi, mg->max_tp_rate); |
| 282 | if (cur_tp < mr->cur_tp) { |
Lorenzo Bianconi | 89888e3 | 2011-09-24 18:48:26 +0200 | [diff] [blame] | 283 | mi->max_tp_rate2 = mi->max_tp_rate; |
| 284 | cur_tp2 = cur_tp; |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 285 | mi->max_tp_rate = mg->max_tp_rate; |
| 286 | cur_tp = mr->cur_tp; |
| 287 | } |
| 288 | |
| 289 | mr = minstrel_get_ratestats(mi, mg->max_tp_rate2); |
| 290 | if (cur_tp2 < mr->cur_tp) { |
| 291 | mi->max_tp_rate2 = mg->max_tp_rate2; |
| 292 | cur_tp2 = mr->cur_tp; |
| 293 | } |
| 294 | } |
| 295 | |
| 296 | mi->stats_update = jiffies; |
| 297 | } |
| 298 | |
| 299 | static bool |
| 300 | minstrel_ht_txstat_valid(struct ieee80211_tx_rate *rate) |
| 301 | { |
Helmut Schaa | b79296b | 2011-11-14 15:28:19 +0100 | [diff] [blame] | 302 | if (rate->idx < 0) |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 303 | return false; |
| 304 | |
Helmut Schaa | b79296b | 2011-11-14 15:28:19 +0100 | [diff] [blame] | 305 | if (!rate->count) |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 306 | return false; |
| 307 | |
| 308 | return !!(rate->flags & IEEE80211_TX_RC_MCS); |
| 309 | } |
| 310 | |
| 311 | static void |
| 312 | minstrel_next_sample_idx(struct minstrel_ht_sta *mi) |
| 313 | { |
| 314 | struct minstrel_mcs_group_data *mg; |
| 315 | |
| 316 | for (;;) { |
| 317 | mi->sample_group++; |
| 318 | mi->sample_group %= ARRAY_SIZE(minstrel_mcs_groups); |
| 319 | mg = &mi->groups[mi->sample_group]; |
| 320 | |
| 321 | if (!mg->supported) |
| 322 | continue; |
| 323 | |
| 324 | if (++mg->index >= MCS_GROUP_RATES) { |
| 325 | mg->index = 0; |
| 326 | if (++mg->column >= ARRAY_SIZE(sample_table)) |
| 327 | mg->column = 0; |
| 328 | } |
| 329 | break; |
| 330 | } |
| 331 | } |
| 332 | |
| 333 | static void |
John W. Linville | d5ece21 | 2010-06-24 11:18:38 -0400 | [diff] [blame] | 334 | minstrel_downgrade_rate(struct minstrel_ht_sta *mi, unsigned int *idx, |
| 335 | bool primary) |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 336 | { |
| 337 | int group, orig_group; |
| 338 | |
| 339 | orig_group = group = *idx / MCS_GROUP_RATES; |
| 340 | while (group > 0) { |
| 341 | group--; |
| 342 | |
| 343 | if (!mi->groups[group].supported) |
| 344 | continue; |
| 345 | |
| 346 | if (minstrel_mcs_groups[group].streams > |
| 347 | minstrel_mcs_groups[orig_group].streams) |
| 348 | continue; |
| 349 | |
| 350 | if (primary) |
| 351 | *idx = mi->groups[group].max_tp_rate; |
| 352 | else |
| 353 | *idx = mi->groups[group].max_tp_rate2; |
| 354 | break; |
| 355 | } |
| 356 | } |
| 357 | |
| 358 | static void |
Patrick Kelle | 6048d763 | 2011-11-15 16:44:48 +0100 | [diff] [blame] | 359 | minstrel_aggr_check(struct ieee80211_sta *pubsta, struct sk_buff *skb) |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 360 | { |
| 361 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; |
| 362 | struct sta_info *sta = container_of(pubsta, struct sta_info, sta); |
| 363 | u16 tid; |
| 364 | |
| 365 | if (unlikely(!ieee80211_is_data_qos(hdr->frame_control))) |
| 366 | return; |
| 367 | |
| 368 | if (unlikely(skb->protocol == cpu_to_be16(ETH_P_PAE))) |
| 369 | return; |
| 370 | |
| 371 | tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; |
Johannes Berg | a622ab7 | 2010-06-10 10:21:39 +0200 | [diff] [blame] | 372 | if (likely(sta->ampdu_mlme.tid_tx[tid])) |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 373 | return; |
| 374 | |
Luis R. Rodriguez | 48124d1 | 2010-11-23 15:05:02 -0800 | [diff] [blame] | 375 | if (skb_get_queue_mapping(skb) == IEEE80211_AC_VO) |
| 376 | return; |
| 377 | |
Sujith Manoharan | bd2ce6e | 2010-12-15 07:47:10 +0530 | [diff] [blame] | 378 | ieee80211_start_tx_ba_session(pubsta, tid, 5000); |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 379 | } |
| 380 | |
| 381 | static void |
| 382 | minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband, |
| 383 | struct ieee80211_sta *sta, void *priv_sta, |
| 384 | struct sk_buff *skb) |
| 385 | { |
| 386 | struct minstrel_ht_sta_priv *msp = priv_sta; |
| 387 | struct minstrel_ht_sta *mi = &msp->ht; |
| 388 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); |
| 389 | struct ieee80211_tx_rate *ar = info->status.rates; |
| 390 | struct minstrel_rate_stats *rate, *rate2; |
| 391 | struct minstrel_priv *mp = priv; |
| 392 | bool last = false; |
| 393 | int group; |
| 394 | int i = 0; |
| 395 | |
| 396 | if (!msp->is_ht) |
| 397 | return mac80211_minstrel.tx_status(priv, sband, sta, &msp->legacy, skb); |
| 398 | |
| 399 | /* This packet was aggregated but doesn't carry status info */ |
| 400 | if ((info->flags & IEEE80211_TX_CTL_AMPDU) && |
| 401 | !(info->flags & IEEE80211_TX_STAT_AMPDU)) |
| 402 | return; |
| 403 | |
Björn Smedman | 15d46f3 | 2010-10-10 22:14:25 +0200 | [diff] [blame] | 404 | if (!(info->flags & IEEE80211_TX_STAT_AMPDU)) { |
| 405 | info->status.ampdu_ack_len = |
| 406 | (info->flags & IEEE80211_TX_STAT_ACK ? 1 : 0); |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 407 | info->status.ampdu_len = 1; |
| 408 | } |
| 409 | |
| 410 | mi->ampdu_packets++; |
| 411 | mi->ampdu_len += info->status.ampdu_len; |
| 412 | |
| 413 | if (!mi->sample_wait && !mi->sample_tries && mi->sample_count > 0) { |
Felix Fietkau | c7317e4 | 2010-10-21 02:47:25 +0200 | [diff] [blame] | 414 | mi->sample_wait = 16 + 2 * MINSTREL_TRUNC(mi->avg_ampdu_len); |
| 415 | mi->sample_tries = 2; |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 416 | mi->sample_count--; |
| 417 | } |
| 418 | |
Daniel Halperin | 8d5eab5 | 2011-03-09 03:10:18 -0800 | [diff] [blame] | 419 | if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE) |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 420 | mi->sample_packets += info->status.ampdu_len; |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 421 | |
| 422 | for (i = 0; !last; i++) { |
| 423 | last = (i == IEEE80211_TX_MAX_RATES - 1) || |
| 424 | !minstrel_ht_txstat_valid(&ar[i + 1]); |
| 425 | |
| 426 | if (!minstrel_ht_txstat_valid(&ar[i])) |
| 427 | break; |
| 428 | |
| 429 | group = minstrel_ht_get_group_idx(&ar[i]); |
| 430 | rate = &mi->groups[group].rates[ar[i].idx % 8]; |
| 431 | |
Björn Smedman | 15d46f3 | 2010-10-10 22:14:25 +0200 | [diff] [blame] | 432 | if (last) |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 433 | rate->success += info->status.ampdu_ack_len; |
| 434 | |
| 435 | rate->attempts += ar[i].count * info->status.ampdu_len; |
| 436 | } |
| 437 | |
| 438 | /* |
| 439 | * check for sudden death of spatial multiplexing, |
| 440 | * downgrade to a lower number of streams if necessary. |
| 441 | */ |
| 442 | rate = minstrel_get_ratestats(mi, mi->max_tp_rate); |
| 443 | if (rate->attempts > 30 && |
| 444 | MINSTREL_FRAC(rate->success, rate->attempts) < |
| 445 | MINSTREL_FRAC(20, 100)) |
| 446 | minstrel_downgrade_rate(mi, &mi->max_tp_rate, true); |
| 447 | |
| 448 | rate2 = minstrel_get_ratestats(mi, mi->max_tp_rate2); |
Ming Lei | ecc3d5a | 2010-07-01 23:19:50 +0800 | [diff] [blame] | 449 | if (rate2->attempts > 30 && |
| 450 | MINSTREL_FRAC(rate2->success, rate2->attempts) < |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 451 | MINSTREL_FRAC(20, 100)) |
| 452 | minstrel_downgrade_rate(mi, &mi->max_tp_rate2, false); |
| 453 | |
| 454 | if (time_after(jiffies, mi->stats_update + (mp->update_interval / 2 * HZ) / 1000)) { |
| 455 | minstrel_ht_update_stats(mp, mi); |
Christian Lamparter | 64ed5cf | 2011-09-03 09:06:20 +0200 | [diff] [blame] | 456 | if (!(info->flags & IEEE80211_TX_CTL_AMPDU)) |
Patrick Kelle | 6048d763 | 2011-11-15 16:44:48 +0100 | [diff] [blame] | 457 | minstrel_aggr_check(sta, skb); |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 458 | } |
| 459 | } |
| 460 | |
| 461 | static void |
| 462 | minstrel_calc_retransmit(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, |
| 463 | int index) |
| 464 | { |
| 465 | struct minstrel_rate_stats *mr; |
| 466 | const struct mcs_group *group; |
| 467 | unsigned int tx_time, tx_time_rtscts, tx_time_data; |
| 468 | unsigned int cw = mp->cw_min; |
Daniel Halperin | 8fddddf | 2011-05-10 19:00:45 -0700 | [diff] [blame] | 469 | unsigned int ctime = 0; |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 470 | unsigned int t_slot = 9; /* FIXME */ |
| 471 | unsigned int ampdu_len = MINSTREL_TRUNC(mi->avg_ampdu_len); |
| 472 | |
| 473 | mr = minstrel_get_ratestats(mi, index); |
| 474 | if (mr->probability < MINSTREL_FRAC(1, 10)) { |
| 475 | mr->retry_count = 1; |
| 476 | mr->retry_count_rtscts = 1; |
| 477 | return; |
| 478 | } |
| 479 | |
| 480 | mr->retry_count = 2; |
| 481 | mr->retry_count_rtscts = 2; |
| 482 | mr->retry_updated = true; |
| 483 | |
| 484 | group = &minstrel_mcs_groups[index / MCS_GROUP_RATES]; |
| 485 | tx_time_data = group->duration[index % MCS_GROUP_RATES] * ampdu_len; |
Daniel Halperin | 8fddddf | 2011-05-10 19:00:45 -0700 | [diff] [blame] | 486 | |
| 487 | /* Contention time for first 2 tries */ |
| 488 | ctime = (t_slot * cw) >> 1; |
| 489 | cw = min((cw << 1) | 1, mp->cw_max); |
| 490 | ctime += (t_slot * cw) >> 1; |
| 491 | cw = min((cw << 1) | 1, mp->cw_max); |
| 492 | |
| 493 | /* Total TX time for data and Contention after first 2 tries */ |
| 494 | tx_time = ctime + 2 * (mi->overhead + tx_time_data); |
| 495 | tx_time_rtscts = ctime + 2 * (mi->overhead_rtscts + tx_time_data); |
| 496 | |
| 497 | /* See how many more tries we can fit inside segment size */ |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 498 | do { |
Daniel Halperin | 8fddddf | 2011-05-10 19:00:45 -0700 | [diff] [blame] | 499 | /* Contention time for this try */ |
| 500 | ctime = (t_slot * cw) >> 1; |
| 501 | cw = min((cw << 1) | 1, mp->cw_max); |
| 502 | |
| 503 | /* Total TX time after this try */ |
| 504 | tx_time += ctime + mi->overhead + tx_time_data; |
| 505 | tx_time_rtscts += ctime + mi->overhead_rtscts + tx_time_data; |
| 506 | |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 507 | if (tx_time_rtscts < mp->segment_size) |
| 508 | mr->retry_count_rtscts++; |
| 509 | } while ((tx_time < mp->segment_size) && |
| 510 | (++mr->retry_count < mp->max_retry)); |
| 511 | } |
| 512 | |
| 513 | |
| 514 | static void |
| 515 | minstrel_ht_set_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, |
| 516 | struct ieee80211_tx_rate *rate, int index, |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 517 | bool sample, bool rtscts) |
| 518 | { |
| 519 | const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES]; |
| 520 | struct minstrel_rate_stats *mr; |
| 521 | |
| 522 | mr = minstrel_get_ratestats(mi, index); |
| 523 | if (!mr->retry_updated) |
| 524 | minstrel_calc_retransmit(mp, mi, index); |
| 525 | |
Felix Fietkau | c7317e4 | 2010-10-21 02:47:25 +0200 | [diff] [blame] | 526 | if (sample) |
| 527 | rate->count = 1; |
| 528 | else if (mr->probability < MINSTREL_FRAC(20, 100)) |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 529 | rate->count = 2; |
| 530 | else if (rtscts) |
| 531 | rate->count = mr->retry_count_rtscts; |
| 532 | else |
| 533 | rate->count = mr->retry_count; |
| 534 | |
| 535 | rate->flags = IEEE80211_TX_RC_MCS | group->flags; |
Helmut Schaa | 9d468d2 | 2011-03-04 13:31:31 +0100 | [diff] [blame] | 536 | if (rtscts) |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 537 | rate->flags |= IEEE80211_TX_RC_USE_RTS_CTS; |
| 538 | rate->idx = index % MCS_GROUP_RATES + (group->streams - 1) * MCS_GROUP_RATES; |
| 539 | } |
| 540 | |
| 541 | static inline int |
| 542 | minstrel_get_duration(int index) |
| 543 | { |
| 544 | const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES]; |
| 545 | return group->duration[index % MCS_GROUP_RATES]; |
| 546 | } |
| 547 | |
| 548 | static int |
| 549 | minstrel_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi) |
| 550 | { |
| 551 | struct minstrel_rate_stats *mr; |
| 552 | struct minstrel_mcs_group_data *mg; |
| 553 | int sample_idx = 0; |
| 554 | |
| 555 | if (mi->sample_wait > 0) { |
| 556 | mi->sample_wait--; |
| 557 | return -1; |
| 558 | } |
| 559 | |
| 560 | if (!mi->sample_tries) |
| 561 | return -1; |
| 562 | |
| 563 | mi->sample_tries--; |
| 564 | mg = &mi->groups[mi->sample_group]; |
| 565 | sample_idx = sample_table[mg->column][mg->index]; |
| 566 | mr = &mg->rates[sample_idx]; |
| 567 | sample_idx += mi->sample_group * MCS_GROUP_RATES; |
Daniel Halperin | 8d5eab5 | 2011-03-09 03:10:18 -0800 | [diff] [blame] | 568 | minstrel_next_sample_idx(mi); |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 569 | |
| 570 | /* |
| 571 | * When not using MRR, do not sample if the probability is already |
| 572 | * higher than 95% to avoid wasting airtime |
| 573 | */ |
| 574 | if (!mp->has_mrr && (mr->probability > MINSTREL_FRAC(95, 100))) |
Daniel Halperin | 8d5eab5 | 2011-03-09 03:10:18 -0800 | [diff] [blame] | 575 | return -1; |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 576 | |
| 577 | /* |
| 578 | * Make sure that lower rates get sampled only occasionally, |
| 579 | * if the link is working perfectly. |
| 580 | */ |
| 581 | if (minstrel_get_duration(sample_idx) > |
| 582 | minstrel_get_duration(mi->max_tp_rate)) { |
Felix Fietkau | c7317e4 | 2010-10-21 02:47:25 +0200 | [diff] [blame] | 583 | if (mr->sample_skipped < 20) |
Daniel Halperin | 8d5eab5 | 2011-03-09 03:10:18 -0800 | [diff] [blame] | 584 | return -1; |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 585 | |
| 586 | if (mi->sample_slow++ > 2) |
Daniel Halperin | 8d5eab5 | 2011-03-09 03:10:18 -0800 | [diff] [blame] | 587 | return -1; |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 588 | } |
| 589 | |
| 590 | return sample_idx; |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 591 | } |
| 592 | |
| 593 | static void |
| 594 | minstrel_ht_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta, |
| 595 | struct ieee80211_tx_rate_control *txrc) |
| 596 | { |
| 597 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb); |
| 598 | struct ieee80211_tx_rate *ar = info->status.rates; |
| 599 | struct minstrel_ht_sta_priv *msp = priv_sta; |
| 600 | struct minstrel_ht_sta *mi = &msp->ht; |
| 601 | struct minstrel_priv *mp = priv; |
| 602 | int sample_idx; |
Felix Fietkau | c7317e4 | 2010-10-21 02:47:25 +0200 | [diff] [blame] | 603 | bool sample = false; |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 604 | |
| 605 | if (rate_control_send_low(sta, priv_sta, txrc)) |
| 606 | return; |
| 607 | |
| 608 | if (!msp->is_ht) |
| 609 | return mac80211_minstrel.get_rate(priv, sta, &msp->legacy, txrc); |
| 610 | |
| 611 | info->flags |= mi->tx_flags; |
Helmut Schaa | 6de062c | 2011-08-01 11:32:53 +0200 | [diff] [blame] | 612 | |
| 613 | /* Don't use EAPOL frames for sampling on non-mrr hw */ |
| 614 | if (mp->hw->max_rates == 1 && |
| 615 | txrc->skb->protocol == cpu_to_be16(ETH_P_PAE)) |
| 616 | sample_idx = -1; |
| 617 | else |
| 618 | sample_idx = minstrel_get_sample_rate(mp, mi); |
Zefir Kurtisi | 24f7580 | 2011-05-20 20:29:17 +0200 | [diff] [blame] | 619 | |
| 620 | #ifdef CONFIG_MAC80211_DEBUGFS |
| 621 | /* use fixed index if set */ |
| 622 | if (mp->fixed_rate_idx != -1) |
| 623 | sample_idx = mp->fixed_rate_idx; |
| 624 | #endif |
| 625 | |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 626 | if (sample_idx >= 0) { |
Felix Fietkau | c7317e4 | 2010-10-21 02:47:25 +0200 | [diff] [blame] | 627 | sample = true; |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 628 | minstrel_ht_set_rate(mp, mi, &ar[0], sample_idx, |
Patrick Kelle | 6048d763 | 2011-11-15 16:44:48 +0100 | [diff] [blame] | 629 | true, false); |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 630 | info->flags |= IEEE80211_TX_CTL_RATE_CTRL_PROBE; |
| 631 | } else { |
| 632 | minstrel_ht_set_rate(mp, mi, &ar[0], mi->max_tp_rate, |
Patrick Kelle | 6048d763 | 2011-11-15 16:44:48 +0100 | [diff] [blame] | 633 | false, false); |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 634 | } |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 635 | |
Helmut Schaa | cf28d79 | 2011-03-09 10:02:38 +0100 | [diff] [blame] | 636 | if (mp->hw->max_rates >= 3) { |
| 637 | /* |
| 638 | * At least 3 tx rates supported, use |
| 639 | * sample_rate -> max_tp_rate -> max_prob_rate for sampling and |
| 640 | * max_tp_rate -> max_tp_rate2 -> max_prob_rate by default. |
| 641 | */ |
| 642 | if (sample_idx >= 0) |
| 643 | minstrel_ht_set_rate(mp, mi, &ar[1], mi->max_tp_rate, |
Patrick Kelle | 6048d763 | 2011-11-15 16:44:48 +0100 | [diff] [blame] | 644 | false, false); |
Helmut Schaa | cf28d79 | 2011-03-09 10:02:38 +0100 | [diff] [blame] | 645 | else |
| 646 | minstrel_ht_set_rate(mp, mi, &ar[1], mi->max_tp_rate2, |
Patrick Kelle | 6048d763 | 2011-11-15 16:44:48 +0100 | [diff] [blame] | 647 | false, true); |
Helmut Schaa | cf28d79 | 2011-03-09 10:02:38 +0100 | [diff] [blame] | 648 | |
| 649 | minstrel_ht_set_rate(mp, mi, &ar[2], mi->max_prob_rate, |
Patrick Kelle | 6048d763 | 2011-11-15 16:44:48 +0100 | [diff] [blame] | 650 | false, !sample); |
Helmut Schaa | cf28d79 | 2011-03-09 10:02:38 +0100 | [diff] [blame] | 651 | |
| 652 | ar[3].count = 0; |
| 653 | ar[3].idx = -1; |
| 654 | } else if (mp->hw->max_rates == 2) { |
| 655 | /* |
| 656 | * Only 2 tx rates supported, use |
| 657 | * sample_rate -> max_prob_rate for sampling and |
| 658 | * max_tp_rate -> max_prob_rate by default. |
| 659 | */ |
| 660 | minstrel_ht_set_rate(mp, mi, &ar[1], mi->max_prob_rate, |
Patrick Kelle | 6048d763 | 2011-11-15 16:44:48 +0100 | [diff] [blame] | 661 | false, !sample); |
Helmut Schaa | cf28d79 | 2011-03-09 10:02:38 +0100 | [diff] [blame] | 662 | |
| 663 | ar[2].count = 0; |
| 664 | ar[2].idx = -1; |
| 665 | } else { |
| 666 | /* Not using MRR, only use the first rate */ |
| 667 | ar[1].count = 0; |
| 668 | ar[1].idx = -1; |
| 669 | } |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 670 | |
| 671 | mi->total_packets++; |
| 672 | |
| 673 | /* wraparound */ |
| 674 | if (mi->total_packets == ~0) { |
| 675 | mi->total_packets = 0; |
| 676 | mi->sample_packets = 0; |
| 677 | } |
| 678 | } |
| 679 | |
| 680 | static void |
| 681 | minstrel_ht_update_caps(void *priv, struct ieee80211_supported_band *sband, |
| 682 | struct ieee80211_sta *sta, void *priv_sta, |
| 683 | enum nl80211_channel_type oper_chan_type) |
| 684 | { |
| 685 | struct minstrel_priv *mp = priv; |
| 686 | struct minstrel_ht_sta_priv *msp = priv_sta; |
| 687 | struct minstrel_ht_sta *mi = &msp->ht; |
| 688 | struct ieee80211_mcs_info *mcs = &sta->ht_cap.mcs; |
| 689 | struct ieee80211_local *local = hw_to_local(mp->hw); |
| 690 | u16 sta_cap = sta->ht_cap.cap; |
Felix Fietkau | 4dc217d | 2011-03-25 15:30:38 +0100 | [diff] [blame] | 691 | int n_supported = 0; |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 692 | int ack_dur; |
| 693 | int stbc; |
| 694 | int i; |
| 695 | |
| 696 | /* fall back to the old minstrel for legacy stations */ |
Felix Fietkau | 4dc217d | 2011-03-25 15:30:38 +0100 | [diff] [blame] | 697 | if (!sta->ht_cap.ht_supported) |
| 698 | goto use_legacy; |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 699 | |
| 700 | BUILD_BUG_ON(ARRAY_SIZE(minstrel_mcs_groups) != |
| 701 | MINSTREL_MAX_STREAMS * MINSTREL_STREAM_GROUPS); |
| 702 | |
| 703 | msp->is_ht = true; |
| 704 | memset(mi, 0, sizeof(*mi)); |
| 705 | mi->stats_update = jiffies; |
| 706 | |
| 707 | ack_dur = ieee80211_frame_duration(local, 10, 60, 1, 1); |
| 708 | mi->overhead = ieee80211_frame_duration(local, 0, 60, 1, 1) + ack_dur; |
| 709 | mi->overhead_rtscts = mi->overhead + 2 * ack_dur; |
| 710 | |
| 711 | mi->avg_ampdu_len = MINSTREL_FRAC(1, 1); |
| 712 | |
| 713 | /* When using MRR, sample more on the first attempt, without delay */ |
| 714 | if (mp->has_mrr) { |
| 715 | mi->sample_count = 16; |
| 716 | mi->sample_wait = 0; |
| 717 | } else { |
| 718 | mi->sample_count = 8; |
| 719 | mi->sample_wait = 8; |
| 720 | } |
| 721 | mi->sample_tries = 4; |
| 722 | |
| 723 | stbc = (sta_cap & IEEE80211_HT_CAP_RX_STBC) >> |
| 724 | IEEE80211_HT_CAP_RX_STBC_SHIFT; |
| 725 | mi->tx_flags |= stbc << IEEE80211_TX_CTL_STBC_SHIFT; |
| 726 | |
| 727 | if (sta_cap & IEEE80211_HT_CAP_LDPC_CODING) |
| 728 | mi->tx_flags |= IEEE80211_TX_CTL_LDPC; |
| 729 | |
| 730 | if (oper_chan_type != NL80211_CHAN_HT40MINUS && |
| 731 | oper_chan_type != NL80211_CHAN_HT40PLUS) |
| 732 | sta_cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40; |
| 733 | |
| 734 | for (i = 0; i < ARRAY_SIZE(mi->groups); i++) { |
| 735 | u16 req = 0; |
| 736 | |
| 737 | mi->groups[i].supported = 0; |
| 738 | if (minstrel_mcs_groups[i].flags & IEEE80211_TX_RC_SHORT_GI) { |
| 739 | if (minstrel_mcs_groups[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH) |
| 740 | req |= IEEE80211_HT_CAP_SGI_40; |
| 741 | else |
| 742 | req |= IEEE80211_HT_CAP_SGI_20; |
| 743 | } |
| 744 | |
| 745 | if (minstrel_mcs_groups[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH) |
| 746 | req |= IEEE80211_HT_CAP_SUP_WIDTH_20_40; |
| 747 | |
| 748 | if ((sta_cap & req) != req) |
| 749 | continue; |
| 750 | |
| 751 | mi->groups[i].supported = |
| 752 | mcs->rx_mask[minstrel_mcs_groups[i].streams - 1]; |
Felix Fietkau | 4dc217d | 2011-03-25 15:30:38 +0100 | [diff] [blame] | 753 | |
| 754 | if (mi->groups[i].supported) |
| 755 | n_supported++; |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 756 | } |
Felix Fietkau | 4dc217d | 2011-03-25 15:30:38 +0100 | [diff] [blame] | 757 | |
| 758 | if (!n_supported) |
| 759 | goto use_legacy; |
| 760 | |
| 761 | return; |
| 762 | |
| 763 | use_legacy: |
| 764 | msp->is_ht = false; |
| 765 | memset(&msp->legacy, 0, sizeof(msp->legacy)); |
| 766 | msp->legacy.r = msp->ratelist; |
| 767 | msp->legacy.sample_table = msp->sample_table; |
| 768 | return mac80211_minstrel.rate_init(priv, sband, sta, &msp->legacy); |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 769 | } |
| 770 | |
| 771 | static void |
| 772 | minstrel_ht_rate_init(void *priv, struct ieee80211_supported_band *sband, |
| 773 | struct ieee80211_sta *sta, void *priv_sta) |
| 774 | { |
| 775 | struct minstrel_priv *mp = priv; |
| 776 | |
| 777 | minstrel_ht_update_caps(priv, sband, sta, priv_sta, mp->hw->conf.channel_type); |
| 778 | } |
| 779 | |
| 780 | static void |
| 781 | minstrel_ht_rate_update(void *priv, struct ieee80211_supported_band *sband, |
| 782 | struct ieee80211_sta *sta, void *priv_sta, |
| 783 | u32 changed, enum nl80211_channel_type oper_chan_type) |
| 784 | { |
| 785 | minstrel_ht_update_caps(priv, sband, sta, priv_sta, oper_chan_type); |
| 786 | } |
| 787 | |
| 788 | static void * |
| 789 | minstrel_ht_alloc_sta(void *priv, struct ieee80211_sta *sta, gfp_t gfp) |
| 790 | { |
| 791 | struct ieee80211_supported_band *sband; |
| 792 | struct minstrel_ht_sta_priv *msp; |
| 793 | struct minstrel_priv *mp = priv; |
| 794 | struct ieee80211_hw *hw = mp->hw; |
| 795 | int max_rates = 0; |
| 796 | int i; |
| 797 | |
| 798 | for (i = 0; i < IEEE80211_NUM_BANDS; i++) { |
| 799 | sband = hw->wiphy->bands[i]; |
| 800 | if (sband && sband->n_bitrates > max_rates) |
| 801 | max_rates = sband->n_bitrates; |
| 802 | } |
| 803 | |
| 804 | msp = kzalloc(sizeof(struct minstrel_ht_sta), gfp); |
| 805 | if (!msp) |
| 806 | return NULL; |
| 807 | |
| 808 | msp->ratelist = kzalloc(sizeof(struct minstrel_rate) * max_rates, gfp); |
| 809 | if (!msp->ratelist) |
| 810 | goto error; |
| 811 | |
| 812 | msp->sample_table = kmalloc(SAMPLE_COLUMNS * max_rates, gfp); |
| 813 | if (!msp->sample_table) |
| 814 | goto error1; |
| 815 | |
| 816 | return msp; |
| 817 | |
| 818 | error1: |
Dan Carpenter | 7e98801 | 2010-07-22 13:14:19 +0200 | [diff] [blame] | 819 | kfree(msp->ratelist); |
Felix Fietkau | ec8aa66 | 2010-05-13 16:48:03 +0200 | [diff] [blame] | 820 | error: |
| 821 | kfree(msp); |
| 822 | return NULL; |
| 823 | } |
| 824 | |
| 825 | static void |
| 826 | minstrel_ht_free_sta(void *priv, struct ieee80211_sta *sta, void *priv_sta) |
| 827 | { |
| 828 | struct minstrel_ht_sta_priv *msp = priv_sta; |
| 829 | |
| 830 | kfree(msp->sample_table); |
| 831 | kfree(msp->ratelist); |
| 832 | kfree(msp); |
| 833 | } |
| 834 | |
| 835 | static void * |
| 836 | minstrel_ht_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir) |
| 837 | { |
| 838 | return mac80211_minstrel.alloc(hw, debugfsdir); |
| 839 | } |
| 840 | |
| 841 | static void |
| 842 | minstrel_ht_free(void *priv) |
| 843 | { |
| 844 | mac80211_minstrel.free(priv); |
| 845 | } |
| 846 | |
| 847 | static struct rate_control_ops mac80211_minstrel_ht = { |
| 848 | .name = "minstrel_ht", |
| 849 | .tx_status = minstrel_ht_tx_status, |
| 850 | .get_rate = minstrel_ht_get_rate, |
| 851 | .rate_init = minstrel_ht_rate_init, |
| 852 | .rate_update = minstrel_ht_rate_update, |
| 853 | .alloc_sta = minstrel_ht_alloc_sta, |
| 854 | .free_sta = minstrel_ht_free_sta, |
| 855 | .alloc = minstrel_ht_alloc, |
| 856 | .free = minstrel_ht_free, |
| 857 | #ifdef CONFIG_MAC80211_DEBUGFS |
| 858 | .add_sta_debugfs = minstrel_ht_add_sta_debugfs, |
| 859 | .remove_sta_debugfs = minstrel_ht_remove_sta_debugfs, |
| 860 | #endif |
| 861 | }; |
| 862 | |
| 863 | |
| 864 | static void |
| 865 | init_sample_table(void) |
| 866 | { |
| 867 | int col, i, new_idx; |
| 868 | u8 rnd[MCS_GROUP_RATES]; |
| 869 | |
| 870 | memset(sample_table, 0xff, sizeof(sample_table)); |
| 871 | for (col = 0; col < SAMPLE_COLUMNS; col++) { |
| 872 | for (i = 0; i < MCS_GROUP_RATES; i++) { |
| 873 | get_random_bytes(rnd, sizeof(rnd)); |
| 874 | new_idx = (i + rnd[i]) % MCS_GROUP_RATES; |
| 875 | |
| 876 | while (sample_table[col][new_idx] != 0xff) |
| 877 | new_idx = (new_idx + 1) % MCS_GROUP_RATES; |
| 878 | |
| 879 | sample_table[col][new_idx] = i; |
| 880 | } |
| 881 | } |
| 882 | } |
| 883 | |
| 884 | int __init |
| 885 | rc80211_minstrel_ht_init(void) |
| 886 | { |
| 887 | init_sample_table(); |
| 888 | return ieee80211_rate_control_register(&mac80211_minstrel_ht); |
| 889 | } |
| 890 | |
| 891 | void |
| 892 | rc80211_minstrel_ht_exit(void) |
| 893 | { |
| 894 | ieee80211_rate_control_unregister(&mac80211_minstrel_ht); |
| 895 | } |