From: Felix Fietkau Date: Sat, 28 Sep 2019 13:57:58 +0000 (+0200) Subject: mac80211: add an improved moving average algorithm to minstrel X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=c51a39d4a5a7bc1e7008c12b79b9236f667ce5ef;p=openwrt%2Fstaging%2Fjow.git mac80211: add an improved moving average algorithm to minstrel Improves rate control responsiveness and performance Signed-off-by: Felix Fietkau [reworked to apply on 4.19.79 mac80211 + renumbered + refreshed] Signed-off-by: Koen Vandeputte --- diff --git a/package/kernel/mac80211/patches/subsys/362-mac80211-minstrel-remove-divisions-in-tx-status-path.patch b/package/kernel/mac80211/patches/subsys/362-mac80211-minstrel-remove-divisions-in-tx-status-path.patch new file mode 100644 index 0000000000..d38d33b41e --- /dev/null +++ b/package/kernel/mac80211/patches/subsys/362-mac80211-minstrel-remove-divisions-in-tx-status-path.patch @@ -0,0 +1,61 @@ +From: Felix Fietkau +Date: Sat, 28 Sep 2019 15:44:06 +0200 +Subject: [PATCH] mac80211: minstrel: remove divisions in tx status path + +Use a slightly different threshold for downgrading spatial streams to +make it easier to calculate without divisions. +Slightly reduces CPU overhead. + +Signed-off-by: Felix Fietkau +--- + +--- a/net/mac80211/rc80211_minstrel.c ++++ b/net/mac80211/rc80211_minstrel.c +@@ -295,8 +295,7 @@ minstrel_tx_status(void *priv, struct ie + if (mi->sample_deferred > 0) + mi->sample_deferred--; + +- if (time_after(jiffies, mi->last_stats_update + +- (mp->update_interval * HZ) / 1000)) ++ if (time_after(jiffies, mi->last_stats_update + mp->update_interval)) + minstrel_update_stats(mp, mi); + } + +--- a/net/mac80211/rc80211_minstrel_ht.c ++++ b/net/mac80211/rc80211_minstrel_ht.c +@@ -937,23 +937,21 @@ minstrel_ht_tx_status(void *priv, struct + */ + rate = minstrel_get_ratestats(mi, mi->max_tp_rate[0]); + if (rate->attempts > 30 && +- MINSTREL_FRAC(rate->success, rate->attempts) < +- MINSTREL_FRAC(20, 100)) { ++ rate->success < rate->attempts / 4) { + minstrel_downgrade_rate(mi, &mi->max_tp_rate[0], true); + update = true; + } + + rate2 = minstrel_get_ratestats(mi, mi->max_tp_rate[1]); + if (rate2->attempts > 30 && +- MINSTREL_FRAC(rate2->success, rate2->attempts) < +- MINSTREL_FRAC(20, 100)) { ++ rate2->success < rate2->attempts / 4) { + minstrel_downgrade_rate(mi, &mi->max_tp_rate[1], false); + update = true; + } + } + + if (time_after(jiffies, mi->last_stats_update + +- (mp->update_interval / 2 * HZ) / 1000)) { ++ mp->update_interval / 2)) { + update = true; + minstrel_ht_update_stats(mp, mi, true); + } +@@ -1640,7 +1638,7 @@ minstrel_ht_alloc(struct ieee80211_hw *h + mp->has_mrr = true; + + mp->hw = hw; +- mp->update_interval = 100; ++ mp->update_interval = HZ / 10; + + #ifdef CPTCFG_MAC80211_DEBUGFS + mp->fixed_rate_idx = (u32) -1; diff --git a/package/kernel/mac80211/patches/subsys/363-mac80211-minstrel_ht-replace-rate-stats-ewma-with-a-.patch b/package/kernel/mac80211/patches/subsys/363-mac80211-minstrel_ht-replace-rate-stats-ewma-with-a-.patch new file mode 100644 index 0000000000..5e2a017865 --- /dev/null +++ b/package/kernel/mac80211/patches/subsys/363-mac80211-minstrel_ht-replace-rate-stats-ewma-with-a-.patch @@ -0,0 +1,235 @@ +From: Felix Fietkau +Date: Sat, 28 Sep 2019 15:46:06 +0200 +Subject: [PATCH] mac80211: minstrel_ht: replace rate stats ewma with a + better moving average + +Rate success probability usually fluctuates a lot under normal conditions. +With a simple EWMA, noise and fluctuation can be reduced by increasing the +window length, but that comes at the cost of introducing lag on sudden +changes. + +This change replaces the EWMA implementation with a moving average that's +designed to significantly reduce lag while keeping a bigger window size +by being better at filtering out noise. + +It is only slightly more expensive than the simple EWMA and still avoids +divisions in its calculation. + +The algorithm is adapted from an implementation intended for a completely +different field (stock market trading), where the tradeoff of lag vs +noise filtering is equally important. + +The algorithm works in the same way as the "smoothing filter" from +http://www.stockspotter.com/files/PredictiveIndicators.pdf adapted for +fixed-point math with some constants, using only addition, bit shifts +and multiplication + +To better make use of the filtering and bigger window size, the update +interval is cut in half. + +For testing, the algorithm can be reverted to the older one via debugfs + +Signed-off-by: Felix Fietkau +--- + +--- a/net/mac80211/rc80211_minstrel.c ++++ b/net/mac80211/rc80211_minstrel.c +@@ -157,14 +157,18 @@ minstrel_update_rates(struct minstrel_pr + * Recalculate statistics and counters of a given rate + */ + void +-minstrel_calc_rate_stats(struct minstrel_rate_stats *mrs) ++minstrel_calc_rate_stats(struct minstrel_priv *mp, ++ struct minstrel_rate_stats *mrs) + { + unsigned int cur_prob; + + if (unlikely(mrs->attempts > 0)) { + mrs->sample_skipped = 0; + cur_prob = MINSTREL_FRAC(mrs->success, mrs->attempts); +- if (unlikely(!mrs->att_hist)) { ++ if (mp->new_avg) { ++ mrs->prob_ewma = minstrel_filter_avg_add(&mrs->avg, ++ cur_prob); ++ } else if (unlikely(!mrs->att_hist)) { + mrs->prob_ewma = cur_prob; + } else { + /* update exponential weighted moving variance */ +@@ -206,7 +210,7 @@ minstrel_update_stats(struct minstrel_pr + struct minstrel_rate_stats *tmp_mrs = &mi->r[tmp_prob_rate].stats; + + /* Update statistics of success probability per rate */ +- minstrel_calc_rate_stats(mrs); ++ minstrel_calc_rate_stats(mp, mrs); + + /* Sample less often below the 10% chance of success. + * Sample less often above the 95% chance of success. */ +@@ -295,7 +299,8 @@ minstrel_tx_status(void *priv, struct ie + if (mi->sample_deferred > 0) + mi->sample_deferred--; + +- if (time_after(jiffies, mi->last_stats_update + mp->update_interval)) ++ if (time_after(jiffies, mi->last_stats_update + ++ mp->update_interval / (mp->new_avg ? 2 : 1))) + minstrel_update_stats(mp, mi); + } + +--- a/net/mac80211/rc80211_minstrel.h ++++ b/net/mac80211/rc80211_minstrel.h +@@ -22,6 +22,21 @@ + #define MAX_THR_RATES 4 + + /* ++ * Coefficients for moving average with noise filter (period=16), ++ * scaled by 10 bits ++ * ++ * a1 = exp(-pi * sqrt(2) / period) ++ * coeff2 = 2 * a1 * cos(sqrt(2) * 2 * pi / period) ++ * coeff3 = -sqr(a1) ++ * coeff1 = 1 - coeff2 - coeff3 ++ */ ++#define MINSTREL_AVG_COEFF1 (MINSTREL_FRAC(1, 1) - \ ++ MINSTREL_AVG_COEFF2 - \ ++ MINSTREL_AVG_COEFF3) ++#define MINSTREL_AVG_COEFF2 0x00001499 ++#define MINSTREL_AVG_COEFF3 -0x0000092e ++ ++/* + * Perform EWMA (Exponentially Weighted Moving Average) calculation + */ + static inline int +@@ -48,6 +63,41 @@ minstrel_ewmv(int old_ewmv, int cur_prob + return weight * (old_ewmv + MINSTREL_TRUNC(diff * incr)) / EWMA_DIV; + } + ++struct minstrel_avg_ctx { ++ s32 prev[2]; ++}; ++ ++static inline int minstrel_filter_avg_add(struct minstrel_avg_ctx *ctx, s32 in) ++{ ++ s32 out_1 = ctx->prev[0]; ++ s32 out_2 = ctx->prev[1]; ++ s32 val; ++ ++ if (!in) ++ in += 1; ++ ++ if (!out_1) { ++ val = out_1 = in; ++ goto out; ++ } ++ ++ val = MINSTREL_AVG_COEFF1 * in; ++ val += MINSTREL_AVG_COEFF2 * out_1; ++ val += MINSTREL_AVG_COEFF3 * out_2; ++ val >>= MINSTREL_SCALE; ++ ++ if (val > 1 << MINSTREL_SCALE) ++ val = 1 << MINSTREL_SCALE; ++ if (val < 0) ++ val = 1; ++ ++out: ++ ctx->prev[1] = out_1; ++ ctx->prev[0] = val; ++ ++ return val; ++} ++ + struct minstrel_rate_stats { + /* current / last sampling period attempts/success counters */ + u16 attempts, last_attempts; +@@ -56,6 +106,8 @@ struct minstrel_rate_stats { + /* total attempts/success counters */ + u32 att_hist, succ_hist; + ++ struct minstrel_avg_ctx avg; ++ + /* statistis of packet delivery probability + * prob_ewma - exponential weighted moving average of prob + * prob_ewmsd - exp. weighted moving standard deviation of prob */ +@@ -114,6 +166,7 @@ struct minstrel_sta_info { + struct minstrel_priv { + struct ieee80211_hw *hw; + bool has_mrr; ++ bool new_avg; + u32 sample_switch; + unsigned int cw_min; + unsigned int cw_max; +@@ -153,7 +206,8 @@ extern const struct rate_control_ops mac + void minstrel_add_sta_debugfs(void *priv, void *priv_sta, struct dentry *dir); + + /* Recalculate success probabilities and counters for a given rate using EWMA */ +-void minstrel_calc_rate_stats(struct minstrel_rate_stats *mrs); ++void minstrel_calc_rate_stats(struct minstrel_priv *mp, ++ struct minstrel_rate_stats *mrs); + int minstrel_get_tp_avg(struct minstrel_rate *mr, int prob_ewma); + + /* debugfs */ +--- a/net/mac80211/rc80211_minstrel_ht.c ++++ b/net/mac80211/rc80211_minstrel_ht.c +@@ -704,7 +704,7 @@ minstrel_ht_update_stats(struct minstrel + + mrs = &mg->rates[i]; + mrs->retry_updated = false; +- minstrel_calc_rate_stats(mrs); ++ minstrel_calc_rate_stats(mp, mrs); + cur_prob = mrs->prob_ewma; + + if (minstrel_ht_get_tp_avg(mi, group, i, cur_prob) == 0) +@@ -740,6 +740,8 @@ minstrel_ht_update_stats(struct minstrel + + /* try to sample all available rates during each interval */ + mi->sample_count *= 8; ++ if (mp->new_avg) ++ mi->sample_count /= 2; + + if (sample) + minstrel_ht_rate_sample_switch(mp, mi); +@@ -856,6 +858,7 @@ minstrel_ht_tx_status(void *priv, struct + struct ieee80211_tx_rate *ar = info->status.rates; + struct minstrel_rate_stats *rate, *rate2, *rate_sample = NULL; + struct minstrel_priv *mp = priv; ++ u32 update_interval = mp->update_interval / 2; + bool last, update = false; + bool sample_status = false; + int i; +@@ -910,6 +913,10 @@ minstrel_ht_tx_status(void *priv, struct + + switch (mi->sample_mode) { + case MINSTREL_SAMPLE_IDLE: ++ if (mp->new_avg && ++ (mp->hw->max_rates > 1 || ++ mi->total_packets_cur < SAMPLE_SWITCH_THR)) ++ update_interval /= 2; + break; + + case MINSTREL_SAMPLE_ACTIVE: +@@ -950,8 +957,7 @@ minstrel_ht_tx_status(void *priv, struct + } + } + +- if (time_after(jiffies, mi->last_stats_update + +- mp->update_interval / 2)) { ++ if (time_after(jiffies, mi->last_stats_update + update_interval)) { + update = true; + minstrel_ht_update_stats(mp, mi, true); + } +@@ -1639,6 +1645,7 @@ minstrel_ht_alloc(struct ieee80211_hw *h + + mp->hw = hw; + mp->update_interval = HZ / 10; ++ mp->new_avg = true; + + #ifdef CPTCFG_MAC80211_DEBUGFS + mp->fixed_rate_idx = (u32) -1; +@@ -1646,6 +1653,8 @@ minstrel_ht_alloc(struct ieee80211_hw *h + &mp->fixed_rate_idx); + debugfs_create_u32("sample_switch", S_IRUGO | S_IWUSR, debugfsdir, + &mp->sample_switch); ++ debugfs_create_bool("new_avg", S_IRUGO | S_IWUSR, debugfsdir, ++ &mp->new_avg); + #endif + + minstrel_ht_init_cck_rates(mp); diff --git a/package/kernel/mac80211/patches/subsys/364-mac80211-minstrel_ht-rename-prob_ewma-to-prob_avg-us.patch b/package/kernel/mac80211/patches/subsys/364-mac80211-minstrel_ht-rename-prob_ewma-to-prob_avg-us.patch new file mode 100644 index 0000000000..c919643505 --- /dev/null +++ b/package/kernel/mac80211/patches/subsys/364-mac80211-minstrel_ht-rename-prob_ewma-to-prob_avg-us.patch @@ -0,0 +1,437 @@ +From: Felix Fietkau +Date: Tue, 8 Oct 2019 18:54:46 +0200 +Subject: [PATCH] mac80211: minstrel_ht: rename prob_ewma to prob_avg, use it + for the new average + +Reduces per-rate data structure size + +Signed-off-by: Felix Fietkau +--- + +--- a/net/mac80211/rc80211_minstrel.c ++++ b/net/mac80211/rc80211_minstrel.c +@@ -70,7 +70,7 @@ rix_to_ndx(struct minstrel_sta_info *mi, + } + + /* return current EMWA throughput */ +-int minstrel_get_tp_avg(struct minstrel_rate *mr, int prob_ewma) ++int minstrel_get_tp_avg(struct minstrel_rate *mr, int prob_avg) + { + int usecs; + +@@ -79,13 +79,13 @@ int minstrel_get_tp_avg(struct minstrel_ + usecs = 1000000; + + /* reset thr. below 10% success */ +- if (mr->stats.prob_ewma < MINSTREL_FRAC(10, 100)) ++ if (mr->stats.prob_avg < MINSTREL_FRAC(10, 100)) + return 0; + +- if (prob_ewma > MINSTREL_FRAC(90, 100)) ++ if (prob_avg > MINSTREL_FRAC(90, 100)) + return MINSTREL_TRUNC(100000 * (MINSTREL_FRAC(90, 100) / usecs)); + else +- return MINSTREL_TRUNC(100000 * (prob_ewma / usecs)); ++ return MINSTREL_TRUNC(100000 * (prob_avg / usecs)); + } + + /* find & sort topmost throughput rates */ +@@ -98,8 +98,8 @@ minstrel_sort_best_tp_rates(struct minst + + for (j = MAX_THR_RATES; j > 0; --j) { + tmp_mrs = &mi->r[tp_list[j - 1]].stats; +- if (minstrel_get_tp_avg(&mi->r[i], cur_mrs->prob_ewma) <= +- minstrel_get_tp_avg(&mi->r[tp_list[j - 1]], tmp_mrs->prob_ewma)) ++ if (minstrel_get_tp_avg(&mi->r[i], cur_mrs->prob_avg) <= ++ minstrel_get_tp_avg(&mi->r[tp_list[j - 1]], tmp_mrs->prob_avg)) + break; + } + +@@ -166,21 +166,21 @@ minstrel_calc_rate_stats(struct minstrel + mrs->sample_skipped = 0; + cur_prob = MINSTREL_FRAC(mrs->success, mrs->attempts); + if (mp->new_avg) { +- mrs->prob_ewma = minstrel_filter_avg_add(&mrs->avg, +- cur_prob); ++ minstrel_filter_avg_add(&mrs->prob_avg, ++ &mrs->prob_avg_1, cur_prob); + } else if (unlikely(!mrs->att_hist)) { +- mrs->prob_ewma = cur_prob; ++ mrs->prob_avg = cur_prob; + } else { + /* update exponential weighted moving variance */ + mrs->prob_ewmv = minstrel_ewmv(mrs->prob_ewmv, + cur_prob, +- mrs->prob_ewma, ++ mrs->prob_avg, + EWMA_LEVEL); + + /*update exponential weighted moving avarage */ +- mrs->prob_ewma = minstrel_ewma(mrs->prob_ewma, +- cur_prob, +- EWMA_LEVEL); ++ mrs->prob_avg = minstrel_ewma(mrs->prob_avg, ++ cur_prob, ++ EWMA_LEVEL); + } + mrs->att_hist += mrs->attempts; + mrs->succ_hist += mrs->success; +@@ -214,8 +214,8 @@ minstrel_update_stats(struct minstrel_pr + + /* Sample less often below the 10% chance of success. + * Sample less often above the 95% chance of success. */ +- if (mrs->prob_ewma > MINSTREL_FRAC(95, 100) || +- mrs->prob_ewma < MINSTREL_FRAC(10, 100)) { ++ if (mrs->prob_avg > MINSTREL_FRAC(95, 100) || ++ mrs->prob_avg < MINSTREL_FRAC(10, 100)) { + mr->adjusted_retry_count = mrs->retry_count >> 1; + if (mr->adjusted_retry_count > 2) + mr->adjusted_retry_count = 2; +@@ -235,14 +235,14 @@ minstrel_update_stats(struct minstrel_pr + * choose the maximum throughput rate as max_prob_rate + * (2) if all success probabilities < 95%, the rate with + * highest success probability is chosen as max_prob_rate */ +- if (mrs->prob_ewma >= MINSTREL_FRAC(95, 100)) { +- tmp_cur_tp = minstrel_get_tp_avg(mr, mrs->prob_ewma); ++ if (mrs->prob_avg >= MINSTREL_FRAC(95, 100)) { ++ tmp_cur_tp = minstrel_get_tp_avg(mr, mrs->prob_avg); + tmp_prob_tp = minstrel_get_tp_avg(&mi->r[tmp_prob_rate], +- tmp_mrs->prob_ewma); ++ tmp_mrs->prob_avg); + if (tmp_cur_tp >= tmp_prob_tp) + tmp_prob_rate = i; + } else { +- if (mrs->prob_ewma >= tmp_mrs->prob_ewma) ++ if (mrs->prob_avg >= tmp_mrs->prob_avg) + tmp_prob_rate = i; + } + } +@@ -436,7 +436,7 @@ minstrel_get_rate(void *priv, struct iee + * has a probability of >95%, we shouldn't be attempting + * to use it, as this only wastes precious airtime */ + if (!mrr_capable && +- (mi->r[ndx].stats.prob_ewma > MINSTREL_FRAC(95, 100))) ++ (mi->r[ndx].stats.prob_avg > MINSTREL_FRAC(95, 100))) + return; + + mi->prev_sample = true; +@@ -587,7 +587,7 @@ static u32 minstrel_get_expected_through + * computing cur_tp + */ + tmp_mrs = &mi->r[idx].stats; +- tmp_cur_tp = minstrel_get_tp_avg(&mi->r[idx], tmp_mrs->prob_ewma) * 10; ++ tmp_cur_tp = minstrel_get_tp_avg(&mi->r[idx], tmp_mrs->prob_avg) * 10; + tmp_cur_tp = tmp_cur_tp * 1200 * 8 / 1024; + + return tmp_cur_tp; +--- a/net/mac80211/rc80211_minstrel.h ++++ b/net/mac80211/rc80211_minstrel.h +@@ -63,14 +63,10 @@ minstrel_ewmv(int old_ewmv, int cur_prob + return weight * (old_ewmv + MINSTREL_TRUNC(diff * incr)) / EWMA_DIV; + } + +-struct minstrel_avg_ctx { +- s32 prev[2]; +-}; +- +-static inline int minstrel_filter_avg_add(struct minstrel_avg_ctx *ctx, s32 in) ++static inline int minstrel_filter_avg_add(u16 *prev_1, u16 *prev_2, s32 in) + { +- s32 out_1 = ctx->prev[0]; +- s32 out_2 = ctx->prev[1]; ++ s32 out_1 = *prev_1; ++ s32 out_2 = *prev_2; + s32 val; + + if (!in) +@@ -92,8 +88,8 @@ static inline int minstrel_filter_avg_ad + val = 1; + + out: +- ctx->prev[1] = out_1; +- ctx->prev[0] = val; ++ *prev_2 = out_1; ++ *prev_1 = val; + + return val; + } +@@ -106,14 +102,15 @@ struct minstrel_rate_stats { + /* total attempts/success counters */ + u32 att_hist, succ_hist; + +- struct minstrel_avg_ctx avg; +- + /* statistis of packet delivery probability + * prob_ewma - exponential weighted moving average of prob + * prob_ewmsd - exp. weighted moving standard deviation of prob */ +- u16 prob_ewma; + u16 prob_ewmv; + ++ /* prob_avg - moving average of prob */ ++ u16 prob_avg; ++ u16 prob_avg_1; ++ + /* maximum retry counts */ + u8 retry_count; + u8 retry_count_rtscts; +@@ -208,7 +205,7 @@ void minstrel_add_sta_debugfs(void *priv + /* Recalculate success probabilities and counters for a given rate using EWMA */ + void minstrel_calc_rate_stats(struct minstrel_priv *mp, + struct minstrel_rate_stats *mrs); +-int minstrel_get_tp_avg(struct minstrel_rate *mr, int prob_ewma); ++int minstrel_get_tp_avg(struct minstrel_rate *mr, int prob_avg); + + /* debugfs */ + int minstrel_stats_open(struct inode *inode, struct file *file); +--- a/net/mac80211/rc80211_minstrel_debugfs.c ++++ b/net/mac80211/rc80211_minstrel_debugfs.c +@@ -91,8 +91,9 @@ minstrel_stats_open(struct inode *inode, + p += sprintf(p, "%6u ", mr->perfect_tx_time); + + tp_max = minstrel_get_tp_avg(mr, MINSTREL_FRAC(100,100)); +- tp_avg = minstrel_get_tp_avg(mr, mrs->prob_ewma); +- eprob = MINSTREL_TRUNC(mrs->prob_ewma * 1000); ++ tp_avg = minstrel_get_tp_avg(mr, mrs->prob_avg); ++ eprob = MINSTREL_TRUNC(mrs->prob_avg * 1000); ++ + prob_ewmsd = minstrel_get_ewmsd10(mrs); + + p += sprintf(p, "%4u.%1u %4u.%1u %3u.%1u %3u.%1u" +@@ -151,8 +152,8 @@ minstrel_stats_csv_open(struct inode *in + p += sprintf(p, "%u,",mr->perfect_tx_time); + + tp_max = minstrel_get_tp_avg(mr, MINSTREL_FRAC(100,100)); +- tp_avg = minstrel_get_tp_avg(mr, mrs->prob_ewma); +- eprob = MINSTREL_TRUNC(mrs->prob_ewma * 1000); ++ tp_avg = minstrel_get_tp_avg(mr, mrs->prob_avg); ++ eprob = MINSTREL_TRUNC(mrs->prob_avg * 1000); + prob_ewmsd = minstrel_get_ewmsd10(mrs); + + p += sprintf(p, "%u.%u,%u.%u,%u.%u,%u.%u,%u,%u,%u," +--- a/net/mac80211/rc80211_minstrel_ht.c ++++ b/net/mac80211/rc80211_minstrel_ht.c +@@ -313,12 +313,12 @@ minstrel_ht_avg_ampdu_len(struct minstre + */ + int + minstrel_ht_get_tp_avg(struct minstrel_ht_sta *mi, int group, int rate, +- int prob_ewma) ++ int prob_avg) + { + unsigned int nsecs = 0; + + /* do not account throughput if sucess prob is below 10% */ +- if (prob_ewma < MINSTREL_FRAC(10, 100)) ++ if (prob_avg < MINSTREL_FRAC(10, 100)) + return 0; + + if (group != MINSTREL_CCK_GROUP) +@@ -332,11 +332,11 @@ minstrel_ht_get_tp_avg(struct minstrel_h + * account for collision related packet error rate fluctuation + * (prob is scaled - see MINSTREL_FRAC above) + */ +- if (prob_ewma > MINSTREL_FRAC(90, 100)) ++ if (prob_avg > MINSTREL_FRAC(90, 100)) + return MINSTREL_TRUNC(100000 * ((MINSTREL_FRAC(90, 100) * 1000) + / nsecs)); + else +- return MINSTREL_TRUNC(100000 * ((prob_ewma * 1000) / nsecs)); ++ return MINSTREL_TRUNC(100000 * ((prob_avg * 1000) / nsecs)); + } + + /* +@@ -356,13 +356,13 @@ minstrel_ht_sort_best_tp_rates(struct mi + + cur_group = index / MCS_GROUP_RATES; + cur_idx = index % MCS_GROUP_RATES; +- cur_prob = mi->groups[cur_group].rates[cur_idx].prob_ewma; ++ cur_prob = mi->groups[cur_group].rates[cur_idx].prob_avg; + cur_tp_avg = minstrel_ht_get_tp_avg(mi, cur_group, cur_idx, cur_prob); + + do { + tmp_group = tp_list[j - 1] / MCS_GROUP_RATES; + tmp_idx = tp_list[j - 1] % MCS_GROUP_RATES; +- tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_ewma; ++ tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_avg; + tmp_tp_avg = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, + tmp_prob); + if (cur_tp_avg < tmp_tp_avg || +@@ -399,7 +399,7 @@ minstrel_ht_set_best_prob_rate(struct mi + + tmp_group = mi->max_prob_rate / MCS_GROUP_RATES; + tmp_idx = mi->max_prob_rate % MCS_GROUP_RATES; +- tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_ewma; ++ tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_avg; + tmp_tp_avg = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, tmp_prob); + + /* if max_tp_rate[0] is from MCS_GROUP max_prob_rate get selected from +@@ -411,11 +411,11 @@ minstrel_ht_set_best_prob_rate(struct mi + + max_gpr_group = mg->max_group_prob_rate / MCS_GROUP_RATES; + max_gpr_idx = mg->max_group_prob_rate % MCS_GROUP_RATES; +- max_gpr_prob = mi->groups[max_gpr_group].rates[max_gpr_idx].prob_ewma; ++ max_gpr_prob = mi->groups[max_gpr_group].rates[max_gpr_idx].prob_avg; + +- if (mrs->prob_ewma > MINSTREL_FRAC(75, 100)) { ++ if (mrs->prob_avg > MINSTREL_FRAC(75, 100)) { + cur_tp_avg = minstrel_ht_get_tp_avg(mi, cur_group, cur_idx, +- mrs->prob_ewma); ++ mrs->prob_avg); + if (cur_tp_avg > tmp_tp_avg) + mi->max_prob_rate = index; + +@@ -425,9 +425,9 @@ minstrel_ht_set_best_prob_rate(struct mi + if (cur_tp_avg > max_gpr_tp_avg) + mg->max_group_prob_rate = index; + } else { +- if (mrs->prob_ewma > tmp_prob) ++ if (mrs->prob_avg > tmp_prob) + mi->max_prob_rate = index; +- if (mrs->prob_ewma > max_gpr_prob) ++ if (mrs->prob_avg > max_gpr_prob) + mg->max_group_prob_rate = index; + } + } +@@ -449,12 +449,12 @@ minstrel_ht_assign_best_tp_rates(struct + + tmp_group = tmp_cck_tp_rate[0] / MCS_GROUP_RATES; + tmp_idx = tmp_cck_tp_rate[0] % MCS_GROUP_RATES; +- tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_ewma; ++ tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_avg; + tmp_cck_tp = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, tmp_prob); + + tmp_group = tmp_mcs_tp_rate[0] / MCS_GROUP_RATES; + tmp_idx = tmp_mcs_tp_rate[0] % MCS_GROUP_RATES; +- tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_ewma; ++ tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_avg; + tmp_mcs_tp = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, tmp_prob); + + if (tmp_cck_tp_rate && tmp_cck_tp > tmp_mcs_tp) { +@@ -485,7 +485,7 @@ minstrel_ht_prob_rate_reduce_streams(str + continue; + + tmp_idx = mg->max_group_prob_rate % MCS_GROUP_RATES; +- tmp_prob = mi->groups[group].rates[tmp_idx].prob_ewma; ++ tmp_prob = mi->groups[group].rates[tmp_idx].prob_avg; + + if (tmp_tp < minstrel_ht_get_tp_avg(mi, group, tmp_idx, tmp_prob) && + (minstrel_mcs_groups[group].streams < tmp_max_streams)) { +@@ -590,7 +590,7 @@ minstrel_ht_rate_sample_switch(struct mi + * If that fails, look again for a rate that is at least as fast + */ + mrs = minstrel_get_ratestats(mi, mi->max_tp_rate[0]); +- faster_rate = mrs->prob_ewma > MINSTREL_FRAC(75, 100); ++ faster_rate = mrs->prob_avg > MINSTREL_FRAC(75, 100); + minstrel_ht_find_probe_rates(mi, rates, &n_rates, faster_rate); + if (!n_rates && faster_rate) + minstrel_ht_find_probe_rates(mi, rates, &n_rates, false); +@@ -705,7 +705,7 @@ minstrel_ht_update_stats(struct minstrel + mrs = &mg->rates[i]; + mrs->retry_updated = false; + minstrel_calc_rate_stats(mp, mrs); +- cur_prob = mrs->prob_ewma; ++ cur_prob = mrs->prob_avg; + + if (minstrel_ht_get_tp_avg(mi, group, i, cur_prob) == 0) + continue; +@@ -979,7 +979,7 @@ minstrel_calc_retransmit(struct minstrel + unsigned int overhead = 0, overhead_rtscts = 0; + + mrs = minstrel_get_ratestats(mi, index); +- if (mrs->prob_ewma < MINSTREL_FRAC(1, 10)) { ++ if (mrs->prob_avg < MINSTREL_FRAC(1, 10)) { + mrs->retry_count = 1; + mrs->retry_count_rtscts = 1; + return; +@@ -1036,7 +1036,7 @@ minstrel_ht_set_rate(struct minstrel_pri + if (!mrs->retry_updated) + minstrel_calc_retransmit(mp, mi, index); + +- if (mrs->prob_ewma < MINSTREL_FRAC(20, 100) || !mrs->retry_count) { ++ if (mrs->prob_avg < MINSTREL_FRAC(20, 100) || !mrs->retry_count) { + ratetbl->rate[offset].count = 2; + ratetbl->rate[offset].count_rts = 2; + ratetbl->rate[offset].count_cts = 2; +@@ -1070,11 +1070,11 @@ minstrel_ht_set_rate(struct minstrel_pri + } + + static inline int +-minstrel_ht_get_prob_ewma(struct minstrel_ht_sta *mi, int rate) ++minstrel_ht_get_prob_avg(struct minstrel_ht_sta *mi, int rate) + { + int group = rate / MCS_GROUP_RATES; + rate %= MCS_GROUP_RATES; +- return mi->groups[group].rates[rate].prob_ewma; ++ return mi->groups[group].rates[rate].prob_avg; + } + + static int +@@ -1086,7 +1086,7 @@ minstrel_ht_get_max_amsdu_len(struct min + unsigned int duration; + + /* Disable A-MSDU if max_prob_rate is bad */ +- if (mi->groups[group].rates[rate].prob_ewma < MINSTREL_FRAC(50, 100)) ++ if (mi->groups[group].rates[rate].prob_avg < MINSTREL_FRAC(50, 100)) + return 1; + + duration = g->duration[rate]; +@@ -1109,7 +1109,7 @@ minstrel_ht_get_max_amsdu_len(struct min + * data packet size + */ + if (duration > MCS_DURATION(1, 0, 260) || +- (minstrel_ht_get_prob_ewma(mi, mi->max_tp_rate[0]) < ++ (minstrel_ht_get_prob_avg(mi, mi->max_tp_rate[0]) < + MINSTREL_FRAC(75, 100))) + return 3200; + +@@ -1216,7 +1216,7 @@ minstrel_get_sample_rate(struct minstrel + * rate, to avoid wasting airtime. + */ + sample_dur = minstrel_get_duration(sample_idx); +- if (mrs->prob_ewma > MINSTREL_FRAC(95, 100) || ++ if (mrs->prob_avg > MINSTREL_FRAC(95, 100) || + minstrel_get_duration(mi->max_prob_rate) * 3 < sample_dur) + return -1; + +@@ -1679,7 +1679,7 @@ static u32 minstrel_ht_get_expected_thro + + i = mi->max_tp_rate[0] / MCS_GROUP_RATES; + j = mi->max_tp_rate[0] % MCS_GROUP_RATES; +- prob = mi->groups[i].rates[j].prob_ewma; ++ prob = mi->groups[i].rates[j].prob_avg; + + /* convert tp_avg from pkt per second in kbps */ + tp_avg = minstrel_ht_get_tp_avg(mi, i, j, prob) * 10; +--- a/net/mac80211/rc80211_minstrel_ht.h ++++ b/net/mac80211/rc80211_minstrel_ht.h +@@ -122,6 +122,6 @@ struct minstrel_ht_sta_priv { + + void minstrel_ht_add_sta_debugfs(void *priv, void *priv_sta, struct dentry *dir); + int minstrel_ht_get_tp_avg(struct minstrel_ht_sta *mi, int group, int rate, +- int prob_ewma); ++ int prob_avg); + + #endif +--- a/net/mac80211/rc80211_minstrel_ht_debugfs.c ++++ b/net/mac80211/rc80211_minstrel_ht_debugfs.c +@@ -102,8 +102,8 @@ minstrel_ht_stats_dump(struct minstrel_h + p += sprintf(p, "%6u ", tx_time); + + tp_max = minstrel_ht_get_tp_avg(mi, i, j, MINSTREL_FRAC(100, 100)); +- tp_avg = minstrel_ht_get_tp_avg(mi, i, j, mrs->prob_ewma); +- eprob = MINSTREL_TRUNC(mrs->prob_ewma * 1000); ++ tp_avg = minstrel_ht_get_tp_avg(mi, i, j, mrs->prob_avg); ++ eprob = MINSTREL_TRUNC(mrs->prob_avg * 1000); + prob_ewmsd = minstrel_get_ewmsd10(mrs); + + p += sprintf(p, "%4u.%1u %4u.%1u %3u.%1u %3u.%1u" +@@ -250,8 +250,8 @@ minstrel_ht_stats_csv_dump(struct minstr + p += sprintf(p, "%u,", tx_time); + + tp_max = minstrel_ht_get_tp_avg(mi, i, j, MINSTREL_FRAC(100, 100)); +- tp_avg = minstrel_ht_get_tp_avg(mi, i, j, mrs->prob_ewma); +- eprob = MINSTREL_TRUNC(mrs->prob_ewma * 1000); ++ tp_avg = minstrel_ht_get_tp_avg(mi, i, j, mrs->prob_avg); ++ eprob = MINSTREL_TRUNC(mrs->prob_avg * 1000); + prob_ewmsd = minstrel_get_ewmsd10(mrs); + + p += sprintf(p, "%u.%u,%u.%u,%u.%u,%u.%u,%u,%u,"