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ec8aa669 | 1 | /* |
a0497f9f | 2 | * Copyright (C) 2010-2013 Felix Fietkau <nbd@openwrt.org> |
ec8aa669 FF |
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> | |
9208247d | 13 | #include <linux/moduleparam.h> |
ec8aa669 FF |
14 | #include <linux/ieee80211.h> |
15 | #include <net/mac80211.h> | |
16 | #include "rate.h" | |
17 | #include "rc80211_minstrel.h" | |
18 | #include "rc80211_minstrel_ht.h" | |
19 | ||
20 | #define AVG_PKT_SIZE 1200 | |
ec8aa669 FF |
21 | |
22 | /* Number of bits for an average sized packet */ | |
23 | #define MCS_NBITS (AVG_PKT_SIZE << 3) | |
24 | ||
25 | /* Number of symbols for a packet with (bps) bits per symbol */ | |
00591cea | 26 | #define MCS_NSYMS(bps) DIV_ROUND_UP(MCS_NBITS, (bps)) |
ec8aa669 | 27 | |
ed97a13c | 28 | /* Transmission time (nanoseconds) for a packet containing (syms) symbols */ |
ec8aa669 FF |
29 | #define MCS_SYMBOL_TIME(sgi, syms) \ |
30 | (sgi ? \ | |
ed97a13c FF |
31 | ((syms) * 18000 + 4000) / 5 : /* syms * 3.6 us */ \ |
32 | ((syms) * 1000) << 2 /* syms * 4 us */ \ | |
ec8aa669 FF |
33 | ) |
34 | ||
35 | /* Transmit duration for the raw data part of an average sized packet */ | |
36 | #define MCS_DURATION(streams, sgi, bps) MCS_SYMBOL_TIME(sgi, MCS_NSYMS((streams) * (bps))) | |
37 | ||
8a0ee4fe KB |
38 | #define BW_20 0 |
39 | #define BW_40 1 | |
9208247d | 40 | #define BW_80 2 |
8a0ee4fe | 41 | |
a5f69d94 HS |
42 | /* |
43 | * Define group sort order: HT40 -> SGI -> #streams | |
44 | */ | |
45 | #define GROUP_IDX(_streams, _sgi, _ht40) \ | |
8a0ee4fe | 46 | MINSTREL_HT_GROUP_0 + \ |
a5f69d94 | 47 | MINSTREL_MAX_STREAMS * 2 * _ht40 + \ |
8a0ee4fe | 48 | MINSTREL_MAX_STREAMS * _sgi + \ |
a5f69d94 HS |
49 | _streams - 1 |
50 | ||
ec8aa669 | 51 | /* MCS rate information for an MCS group */ |
a5f69d94 HS |
52 | #define MCS_GROUP(_streams, _sgi, _ht40) \ |
53 | [GROUP_IDX(_streams, _sgi, _ht40)] = { \ | |
ec8aa669 FF |
54 | .streams = _streams, \ |
55 | .flags = \ | |
3ec373c4 | 56 | IEEE80211_TX_RC_MCS | \ |
ec8aa669 FF |
57 | (_sgi ? IEEE80211_TX_RC_SHORT_GI : 0) | \ |
58 | (_ht40 ? IEEE80211_TX_RC_40_MHZ_WIDTH : 0), \ | |
59 | .duration = { \ | |
60 | MCS_DURATION(_streams, _sgi, _ht40 ? 54 : 26), \ | |
61 | MCS_DURATION(_streams, _sgi, _ht40 ? 108 : 52), \ | |
62 | MCS_DURATION(_streams, _sgi, _ht40 ? 162 : 78), \ | |
63 | MCS_DURATION(_streams, _sgi, _ht40 ? 216 : 104), \ | |
64 | MCS_DURATION(_streams, _sgi, _ht40 ? 324 : 156), \ | |
65 | MCS_DURATION(_streams, _sgi, _ht40 ? 432 : 208), \ | |
66 | MCS_DURATION(_streams, _sgi, _ht40 ? 486 : 234), \ | |
67 | MCS_DURATION(_streams, _sgi, _ht40 ? 540 : 260) \ | |
68 | } \ | |
69 | } | |
70 | ||
9208247d KB |
71 | #define VHT_GROUP_IDX(_streams, _sgi, _bw) \ |
72 | (MINSTREL_VHT_GROUP_0 + \ | |
73 | MINSTREL_MAX_STREAMS * 2 * (_bw) + \ | |
74 | MINSTREL_MAX_STREAMS * (_sgi) + \ | |
75 | (_streams) - 1) | |
76 | ||
77 | #define BW2VBPS(_bw, r3, r2, r1) \ | |
78 | (_bw == BW_80 ? r3 : _bw == BW_40 ? r2 : r1) | |
79 | ||
80 | #define VHT_GROUP(_streams, _sgi, _bw) \ | |
81 | [VHT_GROUP_IDX(_streams, _sgi, _bw)] = { \ | |
82 | .streams = _streams, \ | |
83 | .flags = \ | |
84 | IEEE80211_TX_RC_VHT_MCS | \ | |
85 | (_sgi ? IEEE80211_TX_RC_SHORT_GI : 0) | \ | |
86 | (_bw == BW_80 ? IEEE80211_TX_RC_80_MHZ_WIDTH : \ | |
87 | _bw == BW_40 ? IEEE80211_TX_RC_40_MHZ_WIDTH : 0), \ | |
88 | .duration = { \ | |
89 | MCS_DURATION(_streams, _sgi, \ | |
90 | BW2VBPS(_bw, 117, 54, 26)), \ | |
91 | MCS_DURATION(_streams, _sgi, \ | |
92 | BW2VBPS(_bw, 234, 108, 52)), \ | |
93 | MCS_DURATION(_streams, _sgi, \ | |
94 | BW2VBPS(_bw, 351, 162, 78)), \ | |
95 | MCS_DURATION(_streams, _sgi, \ | |
96 | BW2VBPS(_bw, 468, 216, 104)), \ | |
97 | MCS_DURATION(_streams, _sgi, \ | |
98 | BW2VBPS(_bw, 702, 324, 156)), \ | |
99 | MCS_DURATION(_streams, _sgi, \ | |
100 | BW2VBPS(_bw, 936, 432, 208)), \ | |
101 | MCS_DURATION(_streams, _sgi, \ | |
102 | BW2VBPS(_bw, 1053, 486, 234)), \ | |
103 | MCS_DURATION(_streams, _sgi, \ | |
104 | BW2VBPS(_bw, 1170, 540, 260)), \ | |
105 | MCS_DURATION(_streams, _sgi, \ | |
106 | BW2VBPS(_bw, 1404, 648, 312)), \ | |
107 | MCS_DURATION(_streams, _sgi, \ | |
108 | BW2VBPS(_bw, 1560, 720, 346)) \ | |
109 | } \ | |
110 | } | |
111 | ||
a0497f9f | 112 | #define CCK_DURATION(_bitrate, _short, _len) \ |
ed97a13c | 113 | (1000 * (10 /* SIFS */ + \ |
f359d3fe | 114 | (_short ? 72 + 24 : 144 + 48) + \ |
ed97a13c | 115 | (8 * (_len + 4) * 10) / (_bitrate))) |
a0497f9f FF |
116 | |
117 | #define CCK_ACK_DURATION(_bitrate, _short) \ | |
118 | (CCK_DURATION((_bitrate > 10 ? 20 : 10), false, 60) + \ | |
119 | CCK_DURATION(_bitrate, _short, AVG_PKT_SIZE)) | |
120 | ||
121 | #define CCK_DURATION_LIST(_short) \ | |
122 | CCK_ACK_DURATION(10, _short), \ | |
123 | CCK_ACK_DURATION(20, _short), \ | |
124 | CCK_ACK_DURATION(55, _short), \ | |
125 | CCK_ACK_DURATION(110, _short) | |
126 | ||
8a0ee4fe KB |
127 | #define CCK_GROUP \ |
128 | [MINSTREL_CCK_GROUP] = { \ | |
129 | .streams = 0, \ | |
3ec373c4 | 130 | .flags = 0, \ |
8a0ee4fe KB |
131 | .duration = { \ |
132 | CCK_DURATION_LIST(false), \ | |
133 | CCK_DURATION_LIST(true) \ | |
134 | } \ | |
a0497f9f FF |
135 | } |
136 | ||
9208247d KB |
137 | #ifdef CONFIG_MAC80211_RC_MINSTREL_VHT |
138 | static bool minstrel_vht_only = true; | |
139 | module_param(minstrel_vht_only, bool, 0644); | |
140 | MODULE_PARM_DESC(minstrel_vht_only, | |
141 | "Use only VHT rates when VHT is supported by sta."); | |
142 | #endif | |
143 | ||
ec8aa669 FF |
144 | /* |
145 | * To enable sufficiently targeted rate sampling, MCS rates are divided into | |
146 | * groups, based on the number of streams and flags (HT40, SGI) that they | |
147 | * use. | |
a5f69d94 HS |
148 | * |
149 | * Sortorder has to be fixed for GROUP_IDX macro to be applicable: | |
8a0ee4fe | 150 | * BW -> SGI -> #streams |
ec8aa669 FF |
151 | */ |
152 | const struct mcs_group minstrel_mcs_groups[] = { | |
8a0ee4fe KB |
153 | MCS_GROUP(1, 0, BW_20), |
154 | MCS_GROUP(2, 0, BW_20), | |
ec8aa669 | 155 | #if MINSTREL_MAX_STREAMS >= 3 |
8a0ee4fe | 156 | MCS_GROUP(3, 0, BW_20), |
ec8aa669 FF |
157 | #endif |
158 | ||
8a0ee4fe KB |
159 | MCS_GROUP(1, 1, BW_20), |
160 | MCS_GROUP(2, 1, BW_20), | |
ec8aa669 | 161 | #if MINSTREL_MAX_STREAMS >= 3 |
8a0ee4fe | 162 | MCS_GROUP(3, 1, BW_20), |
ec8aa669 FF |
163 | #endif |
164 | ||
8a0ee4fe KB |
165 | MCS_GROUP(1, 0, BW_40), |
166 | MCS_GROUP(2, 0, BW_40), | |
ec8aa669 | 167 | #if MINSTREL_MAX_STREAMS >= 3 |
8a0ee4fe | 168 | MCS_GROUP(3, 0, BW_40), |
ec8aa669 FF |
169 | #endif |
170 | ||
8a0ee4fe KB |
171 | MCS_GROUP(1, 1, BW_40), |
172 | MCS_GROUP(2, 1, BW_40), | |
ec8aa669 | 173 | #if MINSTREL_MAX_STREAMS >= 3 |
8a0ee4fe | 174 | MCS_GROUP(3, 1, BW_40), |
ec8aa669 | 175 | #endif |
a0497f9f | 176 | |
9208247d KB |
177 | CCK_GROUP, |
178 | ||
179 | #ifdef CONFIG_MAC80211_RC_MINSTREL_VHT | |
180 | VHT_GROUP(1, 0, BW_20), | |
181 | VHT_GROUP(2, 0, BW_20), | |
182 | #if MINSTREL_MAX_STREAMS >= 3 | |
183 | VHT_GROUP(3, 0, BW_20), | |
184 | #endif | |
185 | ||
186 | VHT_GROUP(1, 1, BW_20), | |
187 | VHT_GROUP(2, 1, BW_20), | |
188 | #if MINSTREL_MAX_STREAMS >= 3 | |
189 | VHT_GROUP(3, 1, BW_20), | |
190 | #endif | |
ec8aa669 | 191 | |
9208247d KB |
192 | VHT_GROUP(1, 0, BW_40), |
193 | VHT_GROUP(2, 0, BW_40), | |
194 | #if MINSTREL_MAX_STREAMS >= 3 | |
195 | VHT_GROUP(3, 0, BW_40), | |
196 | #endif | |
197 | ||
198 | VHT_GROUP(1, 1, BW_40), | |
199 | VHT_GROUP(2, 1, BW_40), | |
200 | #if MINSTREL_MAX_STREAMS >= 3 | |
201 | VHT_GROUP(3, 1, BW_40), | |
202 | #endif | |
203 | ||
204 | VHT_GROUP(1, 0, BW_80), | |
205 | VHT_GROUP(2, 0, BW_80), | |
206 | #if MINSTREL_MAX_STREAMS >= 3 | |
207 | VHT_GROUP(3, 0, BW_80), | |
208 | #endif | |
209 | ||
210 | VHT_GROUP(1, 1, BW_80), | |
211 | VHT_GROUP(2, 1, BW_80), | |
212 | #if MINSTREL_MAX_STREAMS >= 3 | |
213 | VHT_GROUP(3, 1, BW_80), | |
214 | #endif | |
215 | #endif | |
216 | }; | |
a0497f9f | 217 | |
f6e1a73b | 218 | static u8 sample_table[SAMPLE_COLUMNS][MCS_GROUP_RATES] __read_mostly; |
ec8aa669 | 219 | |
a8566662 FF |
220 | static void |
221 | minstrel_ht_update_rates(struct minstrel_priv *mp, struct minstrel_ht_sta *mi); | |
222 | ||
9208247d KB |
223 | /* |
224 | * Some VHT MCSes are invalid (when Ndbps / Nes is not an integer) | |
225 | * e.g for MCS9@20MHzx1Nss: Ndbps=8x52*(5/6) Nes=1 | |
226 | * | |
227 | * Returns the valid mcs map for struct minstrel_mcs_group_data.supported | |
228 | */ | |
229 | static u16 | |
230 | minstrel_get_valid_vht_rates(int bw, int nss, __le16 mcs_map) | |
231 | { | |
232 | u16 mask = 0; | |
233 | ||
234 | if (bw == BW_20) { | |
235 | if (nss != 3 && nss != 6) | |
236 | mask = BIT(9); | |
237 | } else if (bw == BW_80) { | |
238 | if (nss == 3 || nss == 7) | |
239 | mask = BIT(6); | |
240 | else if (nss == 6) | |
241 | mask = BIT(9); | |
242 | } else { | |
243 | WARN_ON(bw != BW_40); | |
244 | } | |
245 | ||
246 | switch ((le16_to_cpu(mcs_map) >> (2 * (nss - 1))) & 3) { | |
247 | case IEEE80211_VHT_MCS_SUPPORT_0_7: | |
248 | mask |= 0x300; | |
249 | break; | |
250 | case IEEE80211_VHT_MCS_SUPPORT_0_8: | |
251 | mask |= 0x200; | |
252 | break; | |
253 | case IEEE80211_VHT_MCS_SUPPORT_0_9: | |
254 | break; | |
255 | default: | |
256 | mask = 0x3ff; | |
257 | } | |
258 | ||
259 | return 0x3ff & ~mask; | |
260 | } | |
261 | ||
ec8aa669 FF |
262 | /* |
263 | * Look up an MCS group index based on mac80211 rate information | |
264 | */ | |
265 | static int | |
266 | minstrel_ht_get_group_idx(struct ieee80211_tx_rate *rate) | |
267 | { | |
cc61d8df | 268 | return GROUP_IDX((rate->idx / 8) + 1, |
a5f69d94 HS |
269 | !!(rate->flags & IEEE80211_TX_RC_SHORT_GI), |
270 | !!(rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH)); | |
ec8aa669 FF |
271 | } |
272 | ||
9208247d KB |
273 | static int |
274 | minstrel_vht_get_group_idx(struct ieee80211_tx_rate *rate) | |
275 | { | |
276 | return VHT_GROUP_IDX(ieee80211_rate_get_vht_nss(rate), | |
277 | !!(rate->flags & IEEE80211_TX_RC_SHORT_GI), | |
278 | !!(rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH) + | |
279 | 2*!!(rate->flags & IEEE80211_TX_RC_80_MHZ_WIDTH)); | |
280 | } | |
281 | ||
a0497f9f FF |
282 | static struct minstrel_rate_stats * |
283 | minstrel_ht_get_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, | |
284 | struct ieee80211_tx_rate *rate) | |
285 | { | |
286 | int group, idx; | |
287 | ||
288 | if (rate->flags & IEEE80211_TX_RC_MCS) { | |
289 | group = minstrel_ht_get_group_idx(rate); | |
7a5e3fa2 | 290 | idx = rate->idx % 8; |
9208247d KB |
291 | } else if (rate->flags & IEEE80211_TX_RC_VHT_MCS) { |
292 | group = minstrel_vht_get_group_idx(rate); | |
293 | idx = ieee80211_rate_get_vht_mcs(rate); | |
a0497f9f FF |
294 | } else { |
295 | group = MINSTREL_CCK_GROUP; | |
296 | ||
297 | for (idx = 0; idx < ARRAY_SIZE(mp->cck_rates); idx++) | |
298 | if (rate->idx == mp->cck_rates[idx]) | |
299 | break; | |
300 | ||
301 | /* short preamble */ | |
302 | if (!(mi->groups[group].supported & BIT(idx))) | |
303 | idx += 4; | |
304 | } | |
305 | return &mi->groups[group].rates[idx]; | |
306 | } | |
307 | ||
ec8aa669 FF |
308 | static inline struct minstrel_rate_stats * |
309 | minstrel_get_ratestats(struct minstrel_ht_sta *mi, int index) | |
310 | { | |
311 | return &mi->groups[index / MCS_GROUP_RATES].rates[index % MCS_GROUP_RATES]; | |
312 | } | |
313 | ||
314 | ||
315 | /* | |
316 | * Recalculate success probabilities and counters for a rate using EWMA | |
317 | */ | |
318 | static void | |
6048d763 | 319 | minstrel_calc_rate_ewma(struct minstrel_rate_stats *mr) |
ec8aa669 FF |
320 | { |
321 | if (unlikely(mr->attempts > 0)) { | |
322 | mr->sample_skipped = 0; | |
323 | mr->cur_prob = MINSTREL_FRAC(mr->success, mr->attempts); | |
324 | if (!mr->att_hist) | |
325 | mr->probability = mr->cur_prob; | |
326 | else | |
327 | mr->probability = minstrel_ewma(mr->probability, | |
328 | mr->cur_prob, EWMA_LEVEL); | |
329 | mr->att_hist += mr->attempts; | |
330 | mr->succ_hist += mr->success; | |
331 | } else { | |
332 | mr->sample_skipped++; | |
333 | } | |
334 | mr->last_success = mr->success; | |
335 | mr->last_attempts = mr->attempts; | |
336 | mr->success = 0; | |
337 | mr->attempts = 0; | |
338 | } | |
339 | ||
340 | /* | |
341 | * Calculate throughput based on the average A-MPDU length, taking into account | |
342 | * the expected number of retransmissions and their expected length | |
343 | */ | |
344 | static void | |
6048d763 | 345 | minstrel_ht_calc_tp(struct minstrel_ht_sta *mi, int group, int rate) |
ec8aa669 FF |
346 | { |
347 | struct minstrel_rate_stats *mr; | |
ed97a13c FF |
348 | unsigned int nsecs = 0; |
349 | unsigned int tp; | |
3e8b1eb2 | 350 | unsigned int prob; |
ec8aa669 FF |
351 | |
352 | mr = &mi->groups[group].rates[rate]; | |
3e8b1eb2 | 353 | prob = mr->probability; |
ec8aa669 | 354 | |
3e8b1eb2 | 355 | if (prob < MINSTREL_FRAC(1, 10)) { |
ec8aa669 FF |
356 | mr->cur_tp = 0; |
357 | return; | |
358 | } | |
359 | ||
3e8b1eb2 FF |
360 | /* |
361 | * For the throughput calculation, limit the probability value to 90% to | |
362 | * account for collision related packet error rate fluctuation | |
363 | */ | |
364 | if (prob > MINSTREL_FRAC(9, 10)) | |
365 | prob = MINSTREL_FRAC(9, 10); | |
366 | ||
a0497f9f | 367 | if (group != MINSTREL_CCK_GROUP) |
ed97a13c | 368 | nsecs = 1000 * mi->overhead / MINSTREL_TRUNC(mi->avg_ampdu_len); |
a0497f9f | 369 | |
ed97a13c | 370 | nsecs += minstrel_mcs_groups[group].duration[rate]; |
ed97a13c | 371 | |
00591cea JB |
372 | /* prob is scaled - see MINSTREL_FRAC above */ |
373 | tp = 1000000 * ((prob * 1000) / nsecs); | |
ed97a13c | 374 | mr->cur_tp = MINSTREL_TRUNC(tp); |
ec8aa669 FF |
375 | } |
376 | ||
5935839a TH |
377 | /* |
378 | * Find & sort topmost throughput rates | |
379 | * | |
380 | * If multiple rates provide equal throughput the sorting is based on their | |
381 | * current success probability. Higher success probability is preferred among | |
382 | * MCS groups, CCK rates do not provide aggregation and are therefore at last. | |
383 | */ | |
384 | static void | |
d4d141ca KB |
385 | minstrel_ht_sort_best_tp_rates(struct minstrel_ht_sta *mi, u16 index, |
386 | u16 *tp_list) | |
5935839a TH |
387 | { |
388 | int cur_group, cur_idx, cur_thr, cur_prob; | |
389 | int tmp_group, tmp_idx, tmp_thr, tmp_prob; | |
390 | int j = MAX_THR_RATES; | |
391 | ||
392 | cur_group = index / MCS_GROUP_RATES; | |
393 | cur_idx = index % MCS_GROUP_RATES; | |
394 | cur_thr = mi->groups[cur_group].rates[cur_idx].cur_tp; | |
395 | cur_prob = mi->groups[cur_group].rates[cur_idx].probability; | |
396 | ||
280ba51d | 397 | do { |
5935839a TH |
398 | tmp_group = tp_list[j - 1] / MCS_GROUP_RATES; |
399 | tmp_idx = tp_list[j - 1] % MCS_GROUP_RATES; | |
400 | tmp_thr = mi->groups[tmp_group].rates[tmp_idx].cur_tp; | |
401 | tmp_prob = mi->groups[tmp_group].rates[tmp_idx].probability; | |
280ba51d FF |
402 | if (cur_thr < tmp_thr || |
403 | (cur_thr == tmp_thr && cur_prob <= tmp_prob)) | |
404 | break; | |
405 | j--; | |
406 | } while (j > 0); | |
5935839a TH |
407 | |
408 | if (j < MAX_THR_RATES - 1) { | |
409 | memmove(&tp_list[j + 1], &tp_list[j], (sizeof(*tp_list) * | |
410 | (MAX_THR_RATES - (j + 1)))); | |
411 | } | |
412 | if (j < MAX_THR_RATES) | |
413 | tp_list[j] = index; | |
414 | } | |
415 | ||
416 | /* | |
417 | * Find and set the topmost probability rate per sta and per group | |
418 | */ | |
419 | static void | |
d4d141ca | 420 | minstrel_ht_set_best_prob_rate(struct minstrel_ht_sta *mi, u16 index) |
5935839a TH |
421 | { |
422 | struct minstrel_mcs_group_data *mg; | |
423 | struct minstrel_rate_stats *mr; | |
424 | int tmp_group, tmp_idx, tmp_tp, tmp_prob, max_tp_group; | |
425 | ||
426 | mg = &mi->groups[index / MCS_GROUP_RATES]; | |
427 | mr = &mg->rates[index % MCS_GROUP_RATES]; | |
428 | ||
429 | tmp_group = mi->max_prob_rate / MCS_GROUP_RATES; | |
430 | tmp_idx = mi->max_prob_rate % MCS_GROUP_RATES; | |
431 | tmp_tp = mi->groups[tmp_group].rates[tmp_idx].cur_tp; | |
432 | tmp_prob = mi->groups[tmp_group].rates[tmp_idx].probability; | |
433 | ||
434 | /* if max_tp_rate[0] is from MCS_GROUP max_prob_rate get selected from | |
435 | * MCS_GROUP as well as CCK_GROUP rates do not allow aggregation */ | |
436 | max_tp_group = mi->max_tp_rate[0] / MCS_GROUP_RATES; | |
437 | if((index / MCS_GROUP_RATES == MINSTREL_CCK_GROUP) && | |
438 | (max_tp_group != MINSTREL_CCK_GROUP)) | |
439 | return; | |
440 | ||
441 | if (mr->probability > MINSTREL_FRAC(75, 100)) { | |
442 | if (mr->cur_tp > tmp_tp) | |
443 | mi->max_prob_rate = index; | |
444 | if (mr->cur_tp > mg->rates[mg->max_group_prob_rate].cur_tp) | |
445 | mg->max_group_prob_rate = index; | |
446 | } else { | |
447 | if (mr->probability > tmp_prob) | |
448 | mi->max_prob_rate = index; | |
449 | if (mr->probability > mg->rates[mg->max_group_prob_rate].probability) | |
450 | mg->max_group_prob_rate = index; | |
451 | } | |
452 | } | |
453 | ||
454 | ||
455 | /* | |
456 | * Assign new rate set per sta and use CCK rates only if the fastest | |
457 | * rate (max_tp_rate[0]) is from CCK group. This prohibits such sorted | |
458 | * rate sets where MCS and CCK rates are mixed, because CCK rates can | |
459 | * not use aggregation. | |
460 | */ | |
461 | static void | |
462 | minstrel_ht_assign_best_tp_rates(struct minstrel_ht_sta *mi, | |
d4d141ca KB |
463 | u16 tmp_mcs_tp_rate[MAX_THR_RATES], |
464 | u16 tmp_cck_tp_rate[MAX_THR_RATES]) | |
5935839a TH |
465 | { |
466 | unsigned int tmp_group, tmp_idx, tmp_cck_tp, tmp_mcs_tp; | |
467 | int i; | |
468 | ||
469 | tmp_group = tmp_cck_tp_rate[0] / MCS_GROUP_RATES; | |
470 | tmp_idx = tmp_cck_tp_rate[0] % MCS_GROUP_RATES; | |
471 | tmp_cck_tp = mi->groups[tmp_group].rates[tmp_idx].cur_tp; | |
472 | ||
473 | tmp_group = tmp_mcs_tp_rate[0] / MCS_GROUP_RATES; | |
474 | tmp_idx = tmp_mcs_tp_rate[0] % MCS_GROUP_RATES; | |
475 | tmp_mcs_tp = mi->groups[tmp_group].rates[tmp_idx].cur_tp; | |
476 | ||
477 | if (tmp_cck_tp > tmp_mcs_tp) { | |
478 | for(i = 0; i < MAX_THR_RATES; i++) { | |
479 | minstrel_ht_sort_best_tp_rates(mi, tmp_cck_tp_rate[i], | |
480 | tmp_mcs_tp_rate); | |
481 | } | |
482 | } | |
483 | ||
484 | } | |
485 | ||
486 | /* | |
487 | * Try to increase robustness of max_prob rate by decrease number of | |
488 | * streams if possible. | |
489 | */ | |
490 | static inline void | |
491 | minstrel_ht_prob_rate_reduce_streams(struct minstrel_ht_sta *mi) | |
492 | { | |
493 | struct minstrel_mcs_group_data *mg; | |
494 | struct minstrel_rate_stats *mr; | |
495 | int tmp_max_streams, group; | |
496 | int tmp_tp = 0; | |
497 | ||
498 | tmp_max_streams = minstrel_mcs_groups[mi->max_tp_rate[0] / | |
499 | MCS_GROUP_RATES].streams; | |
500 | for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) { | |
501 | mg = &mi->groups[group]; | |
502 | if (!mg->supported || group == MINSTREL_CCK_GROUP) | |
503 | continue; | |
504 | mr = minstrel_get_ratestats(mi, mg->max_group_prob_rate); | |
505 | if (tmp_tp < mr->cur_tp && | |
506 | (minstrel_mcs_groups[group].streams < tmp_max_streams)) { | |
507 | mi->max_prob_rate = mg->max_group_prob_rate; | |
508 | tmp_tp = mr->cur_tp; | |
509 | } | |
510 | } | |
511 | } | |
512 | ||
ec8aa669 FF |
513 | /* |
514 | * Update rate statistics and select new primary rates | |
515 | * | |
516 | * Rules for rate selection: | |
517 | * - max_prob_rate must use only one stream, as a tradeoff between delivery | |
518 | * probability and throughput during strong fluctuations | |
5935839a | 519 | * - as long as the max prob rate has a probability of more than 75%, pick |
ec8aa669 FF |
520 | * higher throughput rates, even if the probablity is a bit lower |
521 | */ | |
522 | static void | |
523 | minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi) | |
524 | { | |
525 | struct minstrel_mcs_group_data *mg; | |
526 | struct minstrel_rate_stats *mr; | |
5935839a | 527 | int group, i, j; |
d4d141ca KB |
528 | u16 tmp_mcs_tp_rate[MAX_THR_RATES], tmp_group_tp_rate[MAX_THR_RATES]; |
529 | u16 tmp_cck_tp_rate[MAX_THR_RATES], index; | |
ec8aa669 FF |
530 | |
531 | if (mi->ampdu_packets > 0) { | |
532 | mi->avg_ampdu_len = minstrel_ewma(mi->avg_ampdu_len, | |
533 | MINSTREL_FRAC(mi->ampdu_len, mi->ampdu_packets), EWMA_LEVEL); | |
534 | mi->ampdu_len = 0; | |
535 | mi->ampdu_packets = 0; | |
536 | } | |
537 | ||
538 | mi->sample_slow = 0; | |
539 | mi->sample_count = 0; | |
ec8aa669 | 540 | |
5935839a TH |
541 | /* Initialize global rate indexes */ |
542 | for(j = 0; j < MAX_THR_RATES; j++){ | |
543 | tmp_mcs_tp_rate[j] = 0; | |
544 | tmp_cck_tp_rate[j] = 0; | |
545 | } | |
c2eb5b0f | 546 | |
5935839a TH |
547 | /* Find best rate sets within all MCS groups*/ |
548 | for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) { | |
ec8aa669 FF |
549 | |
550 | mg = &mi->groups[group]; | |
551 | if (!mg->supported) | |
552 | continue; | |
553 | ||
ec8aa669 FF |
554 | mi->sample_count++; |
555 | ||
5935839a TH |
556 | /* (re)Initialize group rate indexes */ |
557 | for(j = 0; j < MAX_THR_RATES; j++) | |
558 | tmp_group_tp_rate[j] = group; | |
559 | ||
ec8aa669 FF |
560 | for (i = 0; i < MCS_GROUP_RATES; i++) { |
561 | if (!(mg->supported & BIT(i))) | |
562 | continue; | |
563 | ||
351df099 KB |
564 | index = MCS_GROUP_RATES * group + i; |
565 | ||
ec8aa669 FF |
566 | mr = &mg->rates[i]; |
567 | mr->retry_updated = false; | |
6048d763 PK |
568 | minstrel_calc_rate_ewma(mr); |
569 | minstrel_ht_calc_tp(mi, group, i); | |
ec8aa669 FF |
570 | |
571 | if (!mr->cur_tp) | |
572 | continue; | |
573 | ||
5935839a TH |
574 | /* Find max throughput rate set */ |
575 | if (group != MINSTREL_CCK_GROUP) { | |
576 | minstrel_ht_sort_best_tp_rates(mi, index, | |
577 | tmp_mcs_tp_rate); | |
578 | } else if (group == MINSTREL_CCK_GROUP) { | |
579 | minstrel_ht_sort_best_tp_rates(mi, index, | |
580 | tmp_cck_tp_rate); | |
ec8aa669 | 581 | } |
ec8aa669 | 582 | |
5935839a TH |
583 | /* Find max throughput rate set within a group */ |
584 | minstrel_ht_sort_best_tp_rates(mi, index, | |
585 | tmp_group_tp_rate); | |
ec8aa669 | 586 | |
5935839a TH |
587 | /* Find max probability rate per group and global */ |
588 | minstrel_ht_set_best_prob_rate(mi, index); | |
ec8aa669 FF |
589 | } |
590 | ||
5935839a TH |
591 | memcpy(mg->max_group_tp_rate, tmp_group_tp_rate, |
592 | sizeof(mg->max_group_tp_rate)); | |
ec8aa669 FF |
593 | } |
594 | ||
5935839a TH |
595 | /* Assign new rate set per sta */ |
596 | minstrel_ht_assign_best_tp_rates(mi, tmp_mcs_tp_rate, tmp_cck_tp_rate); | |
597 | memcpy(mi->max_tp_rate, tmp_mcs_tp_rate, sizeof(mi->max_tp_rate)); | |
a299c6d5 | 598 | |
5935839a TH |
599 | /* Try to increase robustness of max_prob_rate*/ |
600 | minstrel_ht_prob_rate_reduce_streams(mi); | |
601 | ||
602 | /* try to sample all available rates during each interval */ | |
603 | mi->sample_count *= 8; | |
a299c6d5 | 604 | |
37feb7e2 LB |
605 | #ifdef CONFIG_MAC80211_DEBUGFS |
606 | /* use fixed index if set */ | |
607 | if (mp->fixed_rate_idx != -1) { | |
5935839a TH |
608 | for (i = 0; i < 4; i++) |
609 | mi->max_tp_rate[i] = mp->fixed_rate_idx; | |
37feb7e2 LB |
610 | mi->max_prob_rate = mp->fixed_rate_idx; |
611 | } | |
612 | #endif | |
a299c6d5 | 613 | |
5935839a | 614 | /* Reset update timer */ |
ec8aa669 FF |
615 | mi->stats_update = jiffies; |
616 | } | |
617 | ||
618 | static bool | |
a0497f9f | 619 | minstrel_ht_txstat_valid(struct minstrel_priv *mp, struct ieee80211_tx_rate *rate) |
ec8aa669 | 620 | { |
b79296be | 621 | if (rate->idx < 0) |
ec8aa669 FF |
622 | return false; |
623 | ||
b79296be | 624 | if (!rate->count) |
ec8aa669 FF |
625 | return false; |
626 | ||
9208247d KB |
627 | if (rate->flags & IEEE80211_TX_RC_MCS || |
628 | rate->flags & IEEE80211_TX_RC_VHT_MCS) | |
a0497f9f FF |
629 | return true; |
630 | ||
631 | return rate->idx == mp->cck_rates[0] || | |
632 | rate->idx == mp->cck_rates[1] || | |
633 | rate->idx == mp->cck_rates[2] || | |
634 | rate->idx == mp->cck_rates[3]; | |
ec8aa669 FF |
635 | } |
636 | ||
637 | static void | |
638 | minstrel_next_sample_idx(struct minstrel_ht_sta *mi) | |
639 | { | |
640 | struct minstrel_mcs_group_data *mg; | |
641 | ||
642 | for (;;) { | |
643 | mi->sample_group++; | |
644 | mi->sample_group %= ARRAY_SIZE(minstrel_mcs_groups); | |
645 | mg = &mi->groups[mi->sample_group]; | |
646 | ||
647 | if (!mg->supported) | |
648 | continue; | |
649 | ||
650 | if (++mg->index >= MCS_GROUP_RATES) { | |
651 | mg->index = 0; | |
652 | if (++mg->column >= ARRAY_SIZE(sample_table)) | |
653 | mg->column = 0; | |
654 | } | |
655 | break; | |
656 | } | |
657 | } | |
658 | ||
659 | static void | |
d4d141ca | 660 | minstrel_downgrade_rate(struct minstrel_ht_sta *mi, u16 *idx, bool primary) |
ec8aa669 FF |
661 | { |
662 | int group, orig_group; | |
663 | ||
664 | orig_group = group = *idx / MCS_GROUP_RATES; | |
665 | while (group > 0) { | |
666 | group--; | |
667 | ||
668 | if (!mi->groups[group].supported) | |
669 | continue; | |
670 | ||
671 | if (minstrel_mcs_groups[group].streams > | |
672 | minstrel_mcs_groups[orig_group].streams) | |
673 | continue; | |
674 | ||
675 | if (primary) | |
5935839a | 676 | *idx = mi->groups[group].max_group_tp_rate[0]; |
ec8aa669 | 677 | else |
5935839a | 678 | *idx = mi->groups[group].max_group_tp_rate[1]; |
ec8aa669 FF |
679 | break; |
680 | } | |
681 | } | |
682 | ||
683 | static void | |
6048d763 | 684 | minstrel_aggr_check(struct ieee80211_sta *pubsta, struct sk_buff *skb) |
ec8aa669 FF |
685 | { |
686 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; | |
687 | struct sta_info *sta = container_of(pubsta, struct sta_info, sta); | |
688 | u16 tid; | |
689 | ||
75769c80 FF |
690 | if (skb_get_queue_mapping(skb) == IEEE80211_AC_VO) |
691 | return; | |
692 | ||
ec8aa669 FF |
693 | if (unlikely(!ieee80211_is_data_qos(hdr->frame_control))) |
694 | return; | |
695 | ||
e133fae2 | 696 | if (unlikely(skb->protocol == cpu_to_be16(ETH_P_PAE))) |
ec8aa669 FF |
697 | return; |
698 | ||
699 | tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; | |
a622ab72 | 700 | if (likely(sta->ampdu_mlme.tid_tx[tid])) |
ec8aa669 FF |
701 | return; |
702 | ||
bd2ce6e4 | 703 | ieee80211_start_tx_ba_session(pubsta, tid, 5000); |
ec8aa669 FF |
704 | } |
705 | ||
706 | static void | |
707 | minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband, | |
708 | struct ieee80211_sta *sta, void *priv_sta, | |
63558a65 | 709 | struct ieee80211_tx_info *info) |
ec8aa669 FF |
710 | { |
711 | struct minstrel_ht_sta_priv *msp = priv_sta; | |
712 | struct minstrel_ht_sta *mi = &msp->ht; | |
ec8aa669 FF |
713 | struct ieee80211_tx_rate *ar = info->status.rates; |
714 | struct minstrel_rate_stats *rate, *rate2; | |
715 | struct minstrel_priv *mp = priv; | |
a8566662 | 716 | bool last, update = false; |
a544ab7f | 717 | int i; |
ec8aa669 FF |
718 | |
719 | if (!msp->is_ht) | |
63558a65 FF |
720 | return mac80211_minstrel.tx_status_noskb(priv, sband, sta, |
721 | &msp->legacy, info); | |
ec8aa669 FF |
722 | |
723 | /* This packet was aggregated but doesn't carry status info */ | |
724 | if ((info->flags & IEEE80211_TX_CTL_AMPDU) && | |
725 | !(info->flags & IEEE80211_TX_STAT_AMPDU)) | |
726 | return; | |
727 | ||
15d46f38 BS |
728 | if (!(info->flags & IEEE80211_TX_STAT_AMPDU)) { |
729 | info->status.ampdu_ack_len = | |
730 | (info->flags & IEEE80211_TX_STAT_ACK ? 1 : 0); | |
ec8aa669 FF |
731 | info->status.ampdu_len = 1; |
732 | } | |
733 | ||
734 | mi->ampdu_packets++; | |
735 | mi->ampdu_len += info->status.ampdu_len; | |
736 | ||
737 | if (!mi->sample_wait && !mi->sample_tries && mi->sample_count > 0) { | |
c7317e41 | 738 | mi->sample_wait = 16 + 2 * MINSTREL_TRUNC(mi->avg_ampdu_len); |
52c00a37 | 739 | mi->sample_tries = 1; |
ec8aa669 FF |
740 | mi->sample_count--; |
741 | } | |
742 | ||
8d5eab5a | 743 | if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE) |
ec8aa669 | 744 | mi->sample_packets += info->status.ampdu_len; |
ec8aa669 | 745 | |
a0497f9f | 746 | last = !minstrel_ht_txstat_valid(mp, &ar[0]); |
ec8aa669 FF |
747 | for (i = 0; !last; i++) { |
748 | last = (i == IEEE80211_TX_MAX_RATES - 1) || | |
a0497f9f | 749 | !minstrel_ht_txstat_valid(mp, &ar[i + 1]); |
ec8aa669 | 750 | |
a0497f9f | 751 | rate = minstrel_ht_get_stats(mp, mi, &ar[i]); |
ec8aa669 | 752 | |
15d46f38 | 753 | if (last) |
ec8aa669 FF |
754 | rate->success += info->status.ampdu_ack_len; |
755 | ||
756 | rate->attempts += ar[i].count * info->status.ampdu_len; | |
757 | } | |
758 | ||
759 | /* | |
760 | * check for sudden death of spatial multiplexing, | |
761 | * downgrade to a lower number of streams if necessary. | |
762 | */ | |
5935839a | 763 | rate = minstrel_get_ratestats(mi, mi->max_tp_rate[0]); |
ec8aa669 FF |
764 | if (rate->attempts > 30 && |
765 | MINSTREL_FRAC(rate->success, rate->attempts) < | |
a8566662 | 766 | MINSTREL_FRAC(20, 100)) { |
5935839a | 767 | minstrel_downgrade_rate(mi, &mi->max_tp_rate[0], true); |
a8566662 FF |
768 | update = true; |
769 | } | |
ec8aa669 | 770 | |
5935839a | 771 | rate2 = minstrel_get_ratestats(mi, mi->max_tp_rate[1]); |
ecc3d5ae ML |
772 | if (rate2->attempts > 30 && |
773 | MINSTREL_FRAC(rate2->success, rate2->attempts) < | |
a8566662 | 774 | MINSTREL_FRAC(20, 100)) { |
5935839a | 775 | minstrel_downgrade_rate(mi, &mi->max_tp_rate[1], false); |
a8566662 FF |
776 | update = true; |
777 | } | |
ec8aa669 FF |
778 | |
779 | if (time_after(jiffies, mi->stats_update + (mp->update_interval / 2 * HZ) / 1000)) { | |
a8566662 | 780 | update = true; |
ec8aa669 | 781 | minstrel_ht_update_stats(mp, mi); |
ec8aa669 | 782 | } |
a8566662 FF |
783 | |
784 | if (update) | |
785 | minstrel_ht_update_rates(mp, mi); | |
ec8aa669 FF |
786 | } |
787 | ||
788 | static void | |
789 | minstrel_calc_retransmit(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, | |
790 | int index) | |
791 | { | |
792 | struct minstrel_rate_stats *mr; | |
793 | const struct mcs_group *group; | |
794 | unsigned int tx_time, tx_time_rtscts, tx_time_data; | |
795 | unsigned int cw = mp->cw_min; | |
8fddddff | 796 | unsigned int ctime = 0; |
ec8aa669 FF |
797 | unsigned int t_slot = 9; /* FIXME */ |
798 | unsigned int ampdu_len = MINSTREL_TRUNC(mi->avg_ampdu_len); | |
a0497f9f | 799 | unsigned int overhead = 0, overhead_rtscts = 0; |
ec8aa669 FF |
800 | |
801 | mr = minstrel_get_ratestats(mi, index); | |
802 | if (mr->probability < MINSTREL_FRAC(1, 10)) { | |
803 | mr->retry_count = 1; | |
804 | mr->retry_count_rtscts = 1; | |
805 | return; | |
806 | } | |
807 | ||
808 | mr->retry_count = 2; | |
809 | mr->retry_count_rtscts = 2; | |
810 | mr->retry_updated = true; | |
811 | ||
812 | group = &minstrel_mcs_groups[index / MCS_GROUP_RATES]; | |
ed97a13c | 813 | tx_time_data = group->duration[index % MCS_GROUP_RATES] * ampdu_len / 1000; |
8fddddff DH |
814 | |
815 | /* Contention time for first 2 tries */ | |
816 | ctime = (t_slot * cw) >> 1; | |
817 | cw = min((cw << 1) | 1, mp->cw_max); | |
818 | ctime += (t_slot * cw) >> 1; | |
819 | cw = min((cw << 1) | 1, mp->cw_max); | |
820 | ||
a0497f9f FF |
821 | if (index / MCS_GROUP_RATES != MINSTREL_CCK_GROUP) { |
822 | overhead = mi->overhead; | |
823 | overhead_rtscts = mi->overhead_rtscts; | |
824 | } | |
825 | ||
8fddddff | 826 | /* Total TX time for data and Contention after first 2 tries */ |
a0497f9f FF |
827 | tx_time = ctime + 2 * (overhead + tx_time_data); |
828 | tx_time_rtscts = ctime + 2 * (overhead_rtscts + tx_time_data); | |
8fddddff DH |
829 | |
830 | /* See how many more tries we can fit inside segment size */ | |
ec8aa669 | 831 | do { |
8fddddff DH |
832 | /* Contention time for this try */ |
833 | ctime = (t_slot * cw) >> 1; | |
834 | cw = min((cw << 1) | 1, mp->cw_max); | |
835 | ||
836 | /* Total TX time after this try */ | |
a0497f9f FF |
837 | tx_time += ctime + overhead + tx_time_data; |
838 | tx_time_rtscts += ctime + overhead_rtscts + tx_time_data; | |
8fddddff | 839 | |
ec8aa669 FF |
840 | if (tx_time_rtscts < mp->segment_size) |
841 | mr->retry_count_rtscts++; | |
842 | } while ((tx_time < mp->segment_size) && | |
843 | (++mr->retry_count < mp->max_retry)); | |
844 | } | |
845 | ||
846 | ||
847 | static void | |
848 | minstrel_ht_set_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, | |
a8566662 | 849 | struct ieee80211_sta_rates *ratetbl, int offset, int index) |
ec8aa669 FF |
850 | { |
851 | const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES]; | |
852 | struct minstrel_rate_stats *mr; | |
a8566662 | 853 | u8 idx; |
3ec373c4 | 854 | u16 flags = group->flags; |
ec8aa669 FF |
855 | |
856 | mr = minstrel_get_ratestats(mi, index); | |
857 | if (!mr->retry_updated) | |
858 | minstrel_calc_retransmit(mp, mi, index); | |
859 | ||
a8566662 FF |
860 | if (mr->probability < MINSTREL_FRAC(20, 100) || !mr->retry_count) { |
861 | ratetbl->rate[offset].count = 2; | |
862 | ratetbl->rate[offset].count_rts = 2; | |
863 | ratetbl->rate[offset].count_cts = 2; | |
864 | } else { | |
865 | ratetbl->rate[offset].count = mr->retry_count; | |
866 | ratetbl->rate[offset].count_cts = mr->retry_count; | |
867 | ratetbl->rate[offset].count_rts = mr->retry_count_rtscts; | |
868 | } | |
a0497f9f | 869 | |
3ec373c4 | 870 | if (index / MCS_GROUP_RATES == MINSTREL_CCK_GROUP) |
a8566662 | 871 | idx = mp->cck_rates[index % ARRAY_SIZE(mp->cck_rates)]; |
9208247d KB |
872 | else if (flags & IEEE80211_TX_RC_VHT_MCS) |
873 | idx = ((group->streams - 1) << 4) | | |
874 | ((index % MCS_GROUP_RATES) & 0xF); | |
3ec373c4 | 875 | else |
7a5e3fa2 | 876 | idx = index % MCS_GROUP_RATES + (group->streams - 1) * 8; |
a8566662 FF |
877 | |
878 | if (offset > 0) { | |
879 | ratetbl->rate[offset].count = ratetbl->rate[offset].count_rts; | |
880 | flags |= IEEE80211_TX_RC_USE_RTS_CTS; | |
881 | } | |
882 | ||
883 | ratetbl->rate[offset].idx = idx; | |
884 | ratetbl->rate[offset].flags = flags; | |
885 | } | |
886 | ||
887 | static void | |
888 | minstrel_ht_update_rates(struct minstrel_priv *mp, struct minstrel_ht_sta *mi) | |
889 | { | |
890 | struct ieee80211_sta_rates *rates; | |
891 | int i = 0; | |
892 | ||
893 | rates = kzalloc(sizeof(*rates), GFP_ATOMIC); | |
894 | if (!rates) | |
a0497f9f | 895 | return; |
a8566662 | 896 | |
5935839a TH |
897 | /* Start with max_tp_rate[0] */ |
898 | minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_tp_rate[0]); | |
a8566662 FF |
899 | |
900 | if (mp->hw->max_rates >= 3) { | |
5935839a TH |
901 | /* At least 3 tx rates supported, use max_tp_rate[1] next */ |
902 | minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_tp_rate[1]); | |
a8566662 FF |
903 | } |
904 | ||
905 | if (mp->hw->max_rates >= 2) { | |
906 | /* | |
907 | * At least 2 tx rates supported, use max_prob_rate next */ | |
908 | minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_prob_rate); | |
a0497f9f FF |
909 | } |
910 | ||
a8566662 FF |
911 | rates->rate[i].idx = -1; |
912 | rate_control_set_rates(mp->hw, mi->sta, rates); | |
ec8aa669 FF |
913 | } |
914 | ||
915 | static inline int | |
916 | minstrel_get_duration(int index) | |
917 | { | |
918 | const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES]; | |
919 | return group->duration[index % MCS_GROUP_RATES]; | |
920 | } | |
921 | ||
922 | static int | |
923 | minstrel_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi) | |
924 | { | |
925 | struct minstrel_rate_stats *mr; | |
926 | struct minstrel_mcs_group_data *mg; | |
5935839a | 927 | unsigned int sample_dur, sample_group, cur_max_tp_streams; |
ec8aa669 FF |
928 | int sample_idx = 0; |
929 | ||
930 | if (mi->sample_wait > 0) { | |
931 | mi->sample_wait--; | |
932 | return -1; | |
933 | } | |
934 | ||
935 | if (!mi->sample_tries) | |
936 | return -1; | |
937 | ||
f12140c0 KB |
938 | sample_group = mi->sample_group; |
939 | mg = &mi->groups[sample_group]; | |
ec8aa669 | 940 | sample_idx = sample_table[mg->column][mg->index]; |
f12140c0 KB |
941 | minstrel_next_sample_idx(mi); |
942 | ||
943 | if (!(mg->supported & BIT(sample_idx))) | |
944 | return -1; | |
945 | ||
ec8aa669 | 946 | mr = &mg->rates[sample_idx]; |
965237ab | 947 | sample_idx += sample_group * MCS_GROUP_RATES; |
ec8aa669 | 948 | |
ba6fa29c HS |
949 | /* |
950 | * Sampling might add some overhead (RTS, no aggregation) | |
951 | * to the frame. Hence, don't use sampling for the currently | |
a0ca796c | 952 | * used rates. |
ba6fa29c | 953 | */ |
5935839a TH |
954 | if (sample_idx == mi->max_tp_rate[0] || |
955 | sample_idx == mi->max_tp_rate[1] || | |
a0ca796c | 956 | sample_idx == mi->max_prob_rate) |
ba6fa29c | 957 | return -1; |
a0ca796c | 958 | |
ec8aa669 | 959 | /* |
bc96f242 FF |
960 | * Do not sample if the probability is already higher than 95% |
961 | * to avoid wasting airtime. | |
ec8aa669 | 962 | */ |
bc96f242 | 963 | if (mr->probability > MINSTREL_FRAC(95, 100)) |
8d5eab5a | 964 | return -1; |
ec8aa669 FF |
965 | |
966 | /* | |
967 | * Make sure that lower rates get sampled only occasionally, | |
968 | * if the link is working perfectly. | |
969 | */ | |
5935839a TH |
970 | |
971 | cur_max_tp_streams = minstrel_mcs_groups[mi->max_tp_rate[0] / | |
972 | MCS_GROUP_RATES].streams; | |
965237ab | 973 | sample_dur = minstrel_get_duration(sample_idx); |
5935839a TH |
974 | if (sample_dur >= minstrel_get_duration(mi->max_tp_rate[1]) && |
975 | (cur_max_tp_streams - 1 < | |
965237ab FF |
976 | minstrel_mcs_groups[sample_group].streams || |
977 | sample_dur >= minstrel_get_duration(mi->max_prob_rate))) { | |
c7317e41 | 978 | if (mr->sample_skipped < 20) |
8d5eab5a | 979 | return -1; |
ec8aa669 FF |
980 | |
981 | if (mi->sample_slow++ > 2) | |
8d5eab5a | 982 | return -1; |
ec8aa669 | 983 | } |
098b8afb | 984 | mi->sample_tries--; |
ec8aa669 FF |
985 | |
986 | return sample_idx; | |
ec8aa669 FF |
987 | } |
988 | ||
a0497f9f FF |
989 | static void |
990 | minstrel_ht_check_cck_shortpreamble(struct minstrel_priv *mp, | |
991 | struct minstrel_ht_sta *mi, bool val) | |
992 | { | |
993 | u8 supported = mi->groups[MINSTREL_CCK_GROUP].supported; | |
994 | ||
995 | if (!supported || !mi->cck_supported_short) | |
996 | return; | |
997 | ||
998 | if (supported & (mi->cck_supported_short << (val * 4))) | |
999 | return; | |
1000 | ||
1001 | supported ^= mi->cck_supported_short | (mi->cck_supported_short << 4); | |
1002 | mi->groups[MINSTREL_CCK_GROUP].supported = supported; | |
1003 | } | |
1004 | ||
ec8aa669 FF |
1005 | static void |
1006 | minstrel_ht_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta, | |
1007 | struct ieee80211_tx_rate_control *txrc) | |
1008 | { | |
a8566662 | 1009 | const struct mcs_group *sample_group; |
ec8aa669 | 1010 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb); |
a8566662 | 1011 | struct ieee80211_tx_rate *rate = &info->status.rates[0]; |
ec8aa669 FF |
1012 | struct minstrel_ht_sta_priv *msp = priv_sta; |
1013 | struct minstrel_ht_sta *mi = &msp->ht; | |
1014 | struct minstrel_priv *mp = priv; | |
1015 | int sample_idx; | |
1016 | ||
1017 | if (rate_control_send_low(sta, priv_sta, txrc)) | |
1018 | return; | |
1019 | ||
1020 | if (!msp->is_ht) | |
1021 | return mac80211_minstrel.get_rate(priv, sta, &msp->legacy, txrc); | |
1022 | ||
95943425 FF |
1023 | if (!(info->flags & IEEE80211_TX_CTL_AMPDU) && |
1024 | mi->max_prob_rate / MCS_GROUP_RATES != MINSTREL_CCK_GROUP) | |
1025 | minstrel_aggr_check(sta, txrc->skb); | |
1026 | ||
ec8aa669 | 1027 | info->flags |= mi->tx_flags; |
a0497f9f | 1028 | minstrel_ht_check_cck_shortpreamble(mp, mi, txrc->short_preamble); |
6de062ce | 1029 | |
37feb7e2 LB |
1030 | #ifdef CONFIG_MAC80211_DEBUGFS |
1031 | if (mp->fixed_rate_idx != -1) | |
1032 | return; | |
1033 | #endif | |
1034 | ||
6de062ce HS |
1035 | /* Don't use EAPOL frames for sampling on non-mrr hw */ |
1036 | if (mp->hw->max_rates == 1 && | |
af61a165 | 1037 | (info->control.flags & IEEE80211_TX_CTRL_PORT_CTRL_PROTO)) |
6de062ce HS |
1038 | sample_idx = -1; |
1039 | else | |
1040 | sample_idx = minstrel_get_sample_rate(mp, mi); | |
24f7580e | 1041 | |
ec8aa669 FF |
1042 | mi->total_packets++; |
1043 | ||
1044 | /* wraparound */ | |
1045 | if (mi->total_packets == ~0) { | |
1046 | mi->total_packets = 0; | |
1047 | mi->sample_packets = 0; | |
1048 | } | |
a8566662 FF |
1049 | |
1050 | if (sample_idx < 0) | |
1051 | return; | |
1052 | ||
1053 | sample_group = &minstrel_mcs_groups[sample_idx / MCS_GROUP_RATES]; | |
1054 | info->flags |= IEEE80211_TX_CTL_RATE_CTRL_PROBE; | |
1cd15857 FF |
1055 | rate->count = 1; |
1056 | ||
1057 | if (sample_idx / MCS_GROUP_RATES == MINSTREL_CCK_GROUP) { | |
1058 | int idx = sample_idx % ARRAY_SIZE(mp->cck_rates); | |
1059 | rate->idx = mp->cck_rates[idx]; | |
9208247d KB |
1060 | } else if (sample_group->flags & IEEE80211_TX_RC_VHT_MCS) { |
1061 | ieee80211_rate_set_vht(rate, sample_idx % MCS_GROUP_RATES, | |
1062 | sample_group->streams); | |
3ec373c4 KB |
1063 | } else { |
1064 | rate->idx = sample_idx % MCS_GROUP_RATES + | |
1065 | (sample_group->streams - 1) * 8; | |
1cd15857 FF |
1066 | } |
1067 | ||
3ec373c4 | 1068 | rate->flags = sample_group->flags; |
ec8aa669 FF |
1069 | } |
1070 | ||
a0497f9f FF |
1071 | static void |
1072 | minstrel_ht_update_cck(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, | |
1073 | struct ieee80211_supported_band *sband, | |
1074 | struct ieee80211_sta *sta) | |
1075 | { | |
1076 | int i; | |
1077 | ||
1078 | if (sband->band != IEEE80211_BAND_2GHZ) | |
1079 | return; | |
1080 | ||
2dfca312 FF |
1081 | if (!(mp->hw->flags & IEEE80211_HW_SUPPORTS_HT_CCK_RATES)) |
1082 | return; | |
1083 | ||
a0497f9f FF |
1084 | mi->cck_supported = 0; |
1085 | mi->cck_supported_short = 0; | |
1086 | for (i = 0; i < 4; i++) { | |
1087 | if (!rate_supported(sta, sband->band, mp->cck_rates[i])) | |
1088 | continue; | |
1089 | ||
1090 | mi->cck_supported |= BIT(i); | |
1091 | if (sband->bitrates[i].flags & IEEE80211_RATE_SHORT_PREAMBLE) | |
1092 | mi->cck_supported_short |= BIT(i); | |
1093 | } | |
1094 | ||
1095 | mi->groups[MINSTREL_CCK_GROUP].supported = mi->cck_supported; | |
1096 | } | |
1097 | ||
ec8aa669 FF |
1098 | static void |
1099 | minstrel_ht_update_caps(void *priv, struct ieee80211_supported_band *sband, | |
3de805cf | 1100 | struct cfg80211_chan_def *chandef, |
64f68e5d | 1101 | struct ieee80211_sta *sta, void *priv_sta) |
ec8aa669 FF |
1102 | { |
1103 | struct minstrel_priv *mp = priv; | |
1104 | struct minstrel_ht_sta_priv *msp = priv_sta; | |
1105 | struct minstrel_ht_sta *mi = &msp->ht; | |
1106 | struct ieee80211_mcs_info *mcs = &sta->ht_cap.mcs; | |
ec8aa669 | 1107 | u16 sta_cap = sta->ht_cap.cap; |
9208247d KB |
1108 | struct ieee80211_sta_vht_cap *vht_cap = &sta->vht_cap; |
1109 | int use_vht; | |
4dc217df | 1110 | int n_supported = 0; |
ec8aa669 FF |
1111 | int ack_dur; |
1112 | int stbc; | |
1113 | int i; | |
1114 | ||
1115 | /* fall back to the old minstrel for legacy stations */ | |
4dc217df FF |
1116 | if (!sta->ht_cap.ht_supported) |
1117 | goto use_legacy; | |
ec8aa669 | 1118 | |
8a0ee4fe | 1119 | BUILD_BUG_ON(ARRAY_SIZE(minstrel_mcs_groups) != MINSTREL_GROUPS_NB); |
ec8aa669 | 1120 | |
9208247d KB |
1121 | #ifdef CONFIG_MAC80211_RC_MINSTREL_VHT |
1122 | if (vht_cap->vht_supported) | |
1123 | use_vht = vht_cap->vht_mcs.tx_mcs_map != cpu_to_le16(~0); | |
1124 | else | |
1125 | #endif | |
1126 | use_vht = 0; | |
1127 | ||
ec8aa669 FF |
1128 | msp->is_ht = true; |
1129 | memset(mi, 0, sizeof(*mi)); | |
a8566662 FF |
1130 | |
1131 | mi->sta = sta; | |
ec8aa669 FF |
1132 | mi->stats_update = jiffies; |
1133 | ||
438b61b7 SW |
1134 | ack_dur = ieee80211_frame_duration(sband->band, 10, 60, 1, 1, 0); |
1135 | mi->overhead = ieee80211_frame_duration(sband->band, 0, 60, 1, 1, 0); | |
1136 | mi->overhead += ack_dur; | |
ec8aa669 FF |
1137 | mi->overhead_rtscts = mi->overhead + 2 * ack_dur; |
1138 | ||
1139 | mi->avg_ampdu_len = MINSTREL_FRAC(1, 1); | |
1140 | ||
1141 | /* When using MRR, sample more on the first attempt, without delay */ | |
1142 | if (mp->has_mrr) { | |
1143 | mi->sample_count = 16; | |
1144 | mi->sample_wait = 0; | |
1145 | } else { | |
1146 | mi->sample_count = 8; | |
1147 | mi->sample_wait = 8; | |
1148 | } | |
1149 | mi->sample_tries = 4; | |
1150 | ||
9208247d KB |
1151 | /* TODO tx_flags for vht - ATM the RC API is not fine-grained enough */ |
1152 | if (!use_vht) { | |
1153 | stbc = (sta_cap & IEEE80211_HT_CAP_RX_STBC) >> | |
1154 | IEEE80211_HT_CAP_RX_STBC_SHIFT; | |
1155 | mi->tx_flags |= stbc << IEEE80211_TX_CTL_STBC_SHIFT; | |
ec8aa669 | 1156 | |
9208247d KB |
1157 | if (sta_cap & IEEE80211_HT_CAP_LDPC_CODING) |
1158 | mi->tx_flags |= IEEE80211_TX_CTL_LDPC; | |
1159 | } | |
ec8aa669 | 1160 | |
ec8aa669 | 1161 | for (i = 0; i < ARRAY_SIZE(mi->groups); i++) { |
3ec373c4 | 1162 | u32 gflags = minstrel_mcs_groups[i].flags; |
9208247d | 1163 | int bw, nss; |
3ec373c4 | 1164 | |
ec8aa669 | 1165 | mi->groups[i].supported = 0; |
a0497f9f FF |
1166 | if (i == MINSTREL_CCK_GROUP) { |
1167 | minstrel_ht_update_cck(mp, mi, sband, sta); | |
1168 | continue; | |
1169 | } | |
1170 | ||
3ec373c4 KB |
1171 | if (gflags & IEEE80211_TX_RC_SHORT_GI) { |
1172 | if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH) { | |
e1a0c6b3 JB |
1173 | if (!(sta_cap & IEEE80211_HT_CAP_SGI_40)) |
1174 | continue; | |
1175 | } else { | |
1176 | if (!(sta_cap & IEEE80211_HT_CAP_SGI_20)) | |
1177 | continue; | |
1178 | } | |
ec8aa669 FF |
1179 | } |
1180 | ||
3ec373c4 | 1181 | if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH && |
e1a0c6b3 | 1182 | sta->bandwidth < IEEE80211_STA_RX_BW_40) |
ec8aa669 FF |
1183 | continue; |
1184 | ||
9208247d KB |
1185 | nss = minstrel_mcs_groups[i].streams; |
1186 | ||
e9219779 | 1187 | /* Mark MCS > 7 as unsupported if STA is in static SMPS mode */ |
9208247d KB |
1188 | if (sta->smps_mode == IEEE80211_SMPS_STATIC && nss > 1) |
1189 | continue; | |
1190 | ||
1191 | /* HT rate */ | |
1192 | if (gflags & IEEE80211_TX_RC_MCS) { | |
1193 | #ifdef CONFIG_MAC80211_RC_MINSTREL_VHT | |
9ffe9044 | 1194 | if (use_vht && minstrel_vht_only) |
9208247d KB |
1195 | continue; |
1196 | #endif | |
1197 | mi->groups[i].supported = mcs->rx_mask[nss - 1]; | |
1198 | if (mi->groups[i].supported) | |
1199 | n_supported++; | |
1200 | continue; | |
1201 | } | |
1202 | ||
1203 | /* VHT rate */ | |
1204 | if (!vht_cap->vht_supported || | |
1205 | WARN_ON(!(gflags & IEEE80211_TX_RC_VHT_MCS)) || | |
1206 | WARN_ON(gflags & IEEE80211_TX_RC_160_MHZ_WIDTH)) | |
e9219779 HS |
1207 | continue; |
1208 | ||
9208247d KB |
1209 | if (gflags & IEEE80211_TX_RC_80_MHZ_WIDTH) { |
1210 | if (sta->bandwidth < IEEE80211_STA_RX_BW_80 || | |
1211 | ((gflags & IEEE80211_TX_RC_SHORT_GI) && | |
1212 | !(vht_cap->cap & IEEE80211_VHT_CAP_SHORT_GI_80))) { | |
1213 | continue; | |
1214 | } | |
1215 | } | |
1216 | ||
1217 | if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH) | |
1218 | bw = BW_40; | |
1219 | else if (gflags & IEEE80211_TX_RC_80_MHZ_WIDTH) | |
1220 | bw = BW_80; | |
1221 | else | |
1222 | bw = BW_20; | |
1223 | ||
1224 | mi->groups[i].supported = minstrel_get_valid_vht_rates(bw, nss, | |
1225 | vht_cap->vht_mcs.tx_mcs_map); | |
4dc217df FF |
1226 | |
1227 | if (mi->groups[i].supported) | |
1228 | n_supported++; | |
ec8aa669 | 1229 | } |
4dc217df FF |
1230 | |
1231 | if (!n_supported) | |
1232 | goto use_legacy; | |
1233 | ||
a8566662 | 1234 | /* create an initial rate table with the lowest supported rates */ |
a3647362 | 1235 | minstrel_ht_update_stats(mp, mi); |
a8566662 | 1236 | minstrel_ht_update_rates(mp, mi); |
a3647362 | 1237 | |
4dc217df FF |
1238 | return; |
1239 | ||
1240 | use_legacy: | |
1241 | msp->is_ht = false; | |
1242 | memset(&msp->legacy, 0, sizeof(msp->legacy)); | |
1243 | msp->legacy.r = msp->ratelist; | |
1244 | msp->legacy.sample_table = msp->sample_table; | |
3de805cf SW |
1245 | return mac80211_minstrel.rate_init(priv, sband, chandef, sta, |
1246 | &msp->legacy); | |
ec8aa669 FF |
1247 | } |
1248 | ||
1249 | static void | |
1250 | minstrel_ht_rate_init(void *priv, struct ieee80211_supported_band *sband, | |
3de805cf | 1251 | struct cfg80211_chan_def *chandef, |
ec8aa669 FF |
1252 | struct ieee80211_sta *sta, void *priv_sta) |
1253 | { | |
3de805cf | 1254 | minstrel_ht_update_caps(priv, sband, chandef, sta, priv_sta); |
ec8aa669 FF |
1255 | } |
1256 | ||
1257 | static void | |
1258 | minstrel_ht_rate_update(void *priv, struct ieee80211_supported_band *sband, | |
3de805cf | 1259 | struct cfg80211_chan_def *chandef, |
ec8aa669 | 1260 | struct ieee80211_sta *sta, void *priv_sta, |
64f68e5d | 1261 | u32 changed) |
ec8aa669 | 1262 | { |
3de805cf | 1263 | minstrel_ht_update_caps(priv, sband, chandef, sta, priv_sta); |
ec8aa669 FF |
1264 | } |
1265 | ||
1266 | static void * | |
1267 | minstrel_ht_alloc_sta(void *priv, struct ieee80211_sta *sta, gfp_t gfp) | |
1268 | { | |
1269 | struct ieee80211_supported_band *sband; | |
1270 | struct minstrel_ht_sta_priv *msp; | |
1271 | struct minstrel_priv *mp = priv; | |
1272 | struct ieee80211_hw *hw = mp->hw; | |
1273 | int max_rates = 0; | |
1274 | int i; | |
1275 | ||
1276 | for (i = 0; i < IEEE80211_NUM_BANDS; i++) { | |
1277 | sband = hw->wiphy->bands[i]; | |
1278 | if (sband && sband->n_bitrates > max_rates) | |
1279 | max_rates = sband->n_bitrates; | |
1280 | } | |
1281 | ||
472dd35c | 1282 | msp = kzalloc(sizeof(*msp), gfp); |
ec8aa669 FF |
1283 | if (!msp) |
1284 | return NULL; | |
1285 | ||
1286 | msp->ratelist = kzalloc(sizeof(struct minstrel_rate) * max_rates, gfp); | |
1287 | if (!msp->ratelist) | |
1288 | goto error; | |
1289 | ||
1290 | msp->sample_table = kmalloc(SAMPLE_COLUMNS * max_rates, gfp); | |
1291 | if (!msp->sample_table) | |
1292 | goto error1; | |
1293 | ||
1294 | return msp; | |
1295 | ||
1296 | error1: | |
7e988014 | 1297 | kfree(msp->ratelist); |
ec8aa669 FF |
1298 | error: |
1299 | kfree(msp); | |
1300 | return NULL; | |
1301 | } | |
1302 | ||
1303 | static void | |
1304 | minstrel_ht_free_sta(void *priv, struct ieee80211_sta *sta, void *priv_sta) | |
1305 | { | |
1306 | struct minstrel_ht_sta_priv *msp = priv_sta; | |
1307 | ||
1308 | kfree(msp->sample_table); | |
1309 | kfree(msp->ratelist); | |
1310 | kfree(msp); | |
1311 | } | |
1312 | ||
1313 | static void * | |
1314 | minstrel_ht_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir) | |
1315 | { | |
1316 | return mac80211_minstrel.alloc(hw, debugfsdir); | |
1317 | } | |
1318 | ||
1319 | static void | |
1320 | minstrel_ht_free(void *priv) | |
1321 | { | |
1322 | mac80211_minstrel.free(priv); | |
1323 | } | |
1324 | ||
cca674d4 AQ |
1325 | static u32 minstrel_ht_get_expected_throughput(void *priv_sta) |
1326 | { | |
1327 | struct minstrel_ht_sta_priv *msp = priv_sta; | |
1328 | struct minstrel_ht_sta *mi = &msp->ht; | |
1329 | int i, j; | |
1330 | ||
1331 | if (!msp->is_ht) | |
1332 | return mac80211_minstrel.get_expected_throughput(priv_sta); | |
1333 | ||
5935839a TH |
1334 | i = mi->max_tp_rate[0] / MCS_GROUP_RATES; |
1335 | j = mi->max_tp_rate[0] % MCS_GROUP_RATES; | |
cca674d4 AQ |
1336 | |
1337 | /* convert cur_tp from pkt per second in kbps */ | |
1338 | return mi->groups[i].rates[j].cur_tp * AVG_PKT_SIZE * 8 / 1024; | |
1339 | } | |
1340 | ||
631ad703 | 1341 | static const struct rate_control_ops mac80211_minstrel_ht = { |
ec8aa669 | 1342 | .name = "minstrel_ht", |
63558a65 | 1343 | .tx_status_noskb = minstrel_ht_tx_status, |
ec8aa669 FF |
1344 | .get_rate = minstrel_ht_get_rate, |
1345 | .rate_init = minstrel_ht_rate_init, | |
1346 | .rate_update = minstrel_ht_rate_update, | |
1347 | .alloc_sta = minstrel_ht_alloc_sta, | |
1348 | .free_sta = minstrel_ht_free_sta, | |
1349 | .alloc = minstrel_ht_alloc, | |
1350 | .free = minstrel_ht_free, | |
1351 | #ifdef CONFIG_MAC80211_DEBUGFS | |
1352 | .add_sta_debugfs = minstrel_ht_add_sta_debugfs, | |
1353 | .remove_sta_debugfs = minstrel_ht_remove_sta_debugfs, | |
1354 | #endif | |
cca674d4 | 1355 | .get_expected_throughput = minstrel_ht_get_expected_throughput, |
ec8aa669 FF |
1356 | }; |
1357 | ||
1358 | ||
f6e1a73b | 1359 | static void __init init_sample_table(void) |
ec8aa669 FF |
1360 | { |
1361 | int col, i, new_idx; | |
1362 | u8 rnd[MCS_GROUP_RATES]; | |
1363 | ||
1364 | memset(sample_table, 0xff, sizeof(sample_table)); | |
1365 | for (col = 0; col < SAMPLE_COLUMNS; col++) { | |
f7d8ad81 | 1366 | prandom_bytes(rnd, sizeof(rnd)); |
ec8aa669 | 1367 | for (i = 0; i < MCS_GROUP_RATES; i++) { |
ec8aa669 | 1368 | new_idx = (i + rnd[i]) % MCS_GROUP_RATES; |
ec8aa669 FF |
1369 | while (sample_table[col][new_idx] != 0xff) |
1370 | new_idx = (new_idx + 1) % MCS_GROUP_RATES; | |
1371 | ||
1372 | sample_table[col][new_idx] = i; | |
1373 | } | |
1374 | } | |
1375 | } | |
1376 | ||
1377 | int __init | |
1378 | rc80211_minstrel_ht_init(void) | |
1379 | { | |
1380 | init_sample_table(); | |
1381 | return ieee80211_rate_control_register(&mac80211_minstrel_ht); | |
1382 | } | |
1383 | ||
1384 | void | |
1385 | rc80211_minstrel_ht_exit(void) | |
1386 | { | |
1387 | ieee80211_rate_control_unregister(&mac80211_minstrel_ht); | |
1388 | } |