Merge tag 'mac80211-next-for-net-next-2019-10-11' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next

Johannes Berg says:

====================
A few more small things, nothing really stands out:
 * minstrel improvements from Felix
 * a TX aggregation simplification
 * some additional capabilities for hwsim
 * minor cleanups & docs updates
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

9 files changed, 141 insertions, 88 deletions

diff --git a/net/mac80211/agg-tx.c b/net/mac80211/agg-tx.c
index b11883d26875..33da6f738c99 100644
--- a/net/mac80211/agg-tx.c
+++ b/net/mac80211/agg-tx.c
@@ -485,7 +485,14 @@ void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
 
 	params.ssn = sta->tid_seq[tid] >> 4;
 	ret = drv_ampdu_action(local, sdata, &params);
-	if (ret) {
+	if (ret == IEEE80211_AMPDU_TX_START_IMMEDIATE) {
+		/*
+		 * We didn't send the request yet, so don't need to check
+		 * here if we already got a response, just mark as driver
+		 * ready immediately.
+		 */
+		set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state);
+	} else if (ret) {
 		ht_dbg(sdata,
 		       "BA request denied - HW unavailable for %pM tid %d\n",
 		       sta->sta.addr, tid);
diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index 0a6ff01c68a9..d40744903fa9 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -538,7 +538,6 @@ int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
 {
 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 	struct cfg80211_bss *cbss;
-	int err, changed = 0;
 
 	sdata_assert_lock(sdata);
 
@@ -560,13 +559,7 @@ int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
 	ifibss->chandef = sdata->csa_chandef;
 
 	/* generate the beacon */
-	err = ieee80211_ibss_csa_beacon(sdata, NULL);
-	if (err < 0)
-		return err;
-
-	changed |= err;
-
-	return changed;
+	return ieee80211_ibss_csa_beacon(sdata, NULL);
 }
 
 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
diff --git a/net/mac80211/rc80211_minstrel.c b/net/mac80211/rc80211_minstrel.c
index ee86c3333999..86bc469a28bc 100644
--- a/net/mac80211/rc80211_minstrel.c
+++ b/net/mac80211/rc80211_minstrel.c
@@ -70,7 +70,7 @@ rix_to_ndx(struct minstrel_sta_info *mi, int rix)
 }
 
 /* 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_rate *mr, int prob_ewma)
 		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 minstrel_sta_info *mi, int i, u8 *tp_list)
 
 	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;
 	}
 
@@ -157,20 +157,24 @@ minstrel_update_rates(struct minstrel_priv *mp, struct minstrel_sta_info *mi)
 * 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)) {
-			mrs->prob_ewma = cur_prob;
+		if (mp->new_avg) {
+			minstrel_filter_avg_add(&mrs->prob_avg,
+						&mrs->prob_avg_1, cur_prob);
+		} else if (unlikely(!mrs->att_hist)) {
+			mrs->prob_avg = cur_prob;
 		} else {
 			/*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;
@@ -200,12 +204,12 @@ minstrel_update_stats(struct minstrel_priv *mp, struct minstrel_sta_info *mi)
 		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. */
-		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;
@@ -225,14 +229,14 @@ minstrel_update_stats(struct minstrel_priv *mp, struct minstrel_sta_info *mi)
 		 * 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;
 		}
 	}
@@ -290,7 +294,7 @@ minstrel_tx_status(void *priv, struct ieee80211_supported_band *sband,
 		mi->sample_deferred--;
 
 	if (time_after(jiffies, mi->last_stats_update +
-				(mp->update_interval * HZ) / 1000))
+				mp->update_interval / (mp->new_avg ? 2 : 1)))
 		minstrel_update_stats(mp, mi);
 }
 
@@ -422,7 +426,7 @@ minstrel_get_rate(void *priv, struct ieee80211_sta *sta,
 	 * 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;
@@ -573,7 +577,7 @@ static u32 minstrel_get_expected_throughput(void *priv_sta)
 	 * 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;
diff --git a/net/mac80211/rc80211_minstrel.h b/net/mac80211/rc80211_minstrel.h
index 51d8b2c846e7..dbb43bcd3c45 100644
--- a/net/mac80211/rc80211_minstrel.h
+++ b/net/mac80211/rc80211_minstrel.h
@@ -19,6 +19,21 @@
 #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
@@ -32,6 +47,37 @@ minstrel_ewma(int old, int new, int weight)
 	return old + incr;
 }
 
+static inline int minstrel_filter_avg_add(u16 *prev_1, u16 *prev_2, s32 in)
+{
+	s32 out_1 = *prev_1;
+	s32 out_2 = *prev_2;
+	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:
+	*prev_2 = out_1;
+	*prev_1 = val;
+
+	return val;
+}
+
 struct minstrel_rate_stats {
 	/* current / last sampling period attempts/success counters */
 	u16 attempts, last_attempts;
@@ -40,8 +86,9 @@ struct minstrel_rate_stats {
 	/* total attempts/success counters */
 	u32 att_hist, succ_hist;
 
-	/* prob_ewma - exponential weighted moving average of prob */
-	u16 prob_ewma;
+	/* prob_avg - moving average of prob */
+	u16 prob_avg;
+	u16 prob_avg_1;
 
 	/* maximum retry counts */
 	u8 retry_count;
@@ -95,6 +142,7 @@ 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;
@@ -126,8 +174,9 @@ extern const struct rate_control_ops mac80211_minstrel;
 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);
-int minstrel_get_tp_avg(struct minstrel_rate *mr, int prob_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_avg);
 
 /* debugfs */
 int minstrel_stats_open(struct inode *inode, struct file *file);
diff --git a/net/mac80211/rc80211_minstrel_debugfs.c b/net/mac80211/rc80211_minstrel_debugfs.c
index c8afd85b51a0..9b8e0daeb7bb 100644
--- a/net/mac80211/rc80211_minstrel_debugfs.c
+++ b/net/mac80211/rc80211_minstrel_debugfs.c
@@ -90,8 +90,8 @@ minstrel_stats_open(struct inode *inode, struct file *file)
 		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);
 
 		p += sprintf(p, "%4u.%1u    %4u.%1u     %3u.%1u"
 				"     %3u   %3u %-3u   "
@@ -147,8 +147,8 @@ minstrel_stats_csv_open(struct inode *inode, struct file *file)
 		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);
 
 		p += sprintf(p, "%u.%u,%u.%u,%u.%u,%u,%u,%u,"
 				"%llu,%llu,%d,%d\n",
diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c
index 0ef2633349b5..694a31978a04 100644
--- a/net/mac80211/rc80211_minstrel_ht.c
+++ b/net/mac80211/rc80211_minstrel_ht.c
@@ -346,12 +346,12 @@ minstrel_ht_avg_ampdu_len(struct minstrel_ht_sta *mi)
  */
 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)
@@ -365,11 +365,11 @@ minstrel_ht_get_tp_avg(struct minstrel_ht_sta *mi, int group, int rate,
 	 * 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));
 }
 
 /*
@@ -389,13 +389,13 @@ minstrel_ht_sort_best_tp_rates(struct minstrel_ht_sta *mi, u16 index,
 
 	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 ||
@@ -432,7 +432,7 @@ minstrel_ht_set_best_prob_rate(struct minstrel_ht_sta *mi, u16 index)
 
 	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
@@ -444,11 +444,11 @@ minstrel_ht_set_best_prob_rate(struct minstrel_ht_sta *mi, u16 index)
 
 	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;
 
@@ -458,9 +458,9 @@ minstrel_ht_set_best_prob_rate(struct minstrel_ht_sta *mi, u16 index)
 		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;
 	}
 }
@@ -482,12 +482,12 @@ minstrel_ht_assign_best_tp_rates(struct minstrel_ht_sta *mi,
 
 	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) {
@@ -518,7 +518,7 @@ minstrel_ht_prob_rate_reduce_streams(struct minstrel_ht_sta *mi)
 			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)) {
@@ -623,7 +623,7 @@ minstrel_ht_rate_sample_switch(struct minstrel_priv *mp,
 	 * 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);
@@ -737,8 +737,8 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
 
 			mrs = &mg->rates[i];
 			mrs->retry_updated = false;
-			minstrel_calc_rate_stats(mrs);
-			cur_prob = mrs->prob_ewma;
+			minstrel_calc_rate_stats(mp, mrs);
+			cur_prob = mrs->prob_avg;
 
 			if (minstrel_ht_get_tp_avg(mi, group, i, cur_prob) == 0)
 				continue;
@@ -773,6 +773,8 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
 
 	/* 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);
@@ -889,6 +891,7 @@ minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband,
 	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;
@@ -943,6 +946,10 @@ minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband,
 
 	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:
@@ -970,23 +977,20 @@ minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband,
 		 */
 		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)) {
+	if (time_after(jiffies, mi->last_stats_update + update_interval)) {
 		update = true;
 		minstrel_ht_update_stats(mp, mi, true);
 	}
@@ -1008,7 +1012,7 @@ minstrel_calc_retransmit(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
 	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;
@@ -1065,7 +1069,7 @@ minstrel_ht_set_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
 	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;
@@ -1099,11 +1103,11 @@ minstrel_ht_set_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
 }
 
 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
@@ -1115,7 +1119,7 @@ minstrel_ht_get_max_amsdu_len(struct minstrel_ht_sta *mi)
 	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];
@@ -1138,7 +1142,7 @@ minstrel_ht_get_max_amsdu_len(struct minstrel_ht_sta *mi)
 	 * 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;
 
@@ -1243,7 +1247,7 @@ minstrel_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
 	 * 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;
 
@@ -1666,7 +1670,8 @@ minstrel_ht_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
 		mp->has_mrr = true;
 
 	mp->hw = hw;
-	mp->update_interval = 100;
+	mp->update_interval = HZ / 10;
+	mp->new_avg = true;
 
 #ifdef CONFIG_MAC80211_DEBUGFS
 	mp->fixed_rate_idx = (u32) -1;
@@ -1674,6 +1679,8 @@ minstrel_ht_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
 			   &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);
@@ -1698,7 +1705,7 @@ static u32 minstrel_ht_get_expected_throughput(void *priv_sta)
 
 	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;
diff --git a/net/mac80211/rc80211_minstrel_ht.h b/net/mac80211/rc80211_minstrel_ht.h
index f938701e7ab7..53ea3c29debf 100644
--- a/net/mac80211/rc80211_minstrel_ht.h
+++ b/net/mac80211/rc80211_minstrel_ht.h
@@ -119,6 +119,6 @@ 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
diff --git a/net/mac80211/rc80211_minstrel_ht_debugfs.c b/net/mac80211/rc80211_minstrel_ht_debugfs.c
index 5a6e9f3edc04..bebb71917742 100644
--- a/net/mac80211/rc80211_minstrel_ht_debugfs.c
+++ b/net/mac80211/rc80211_minstrel_ht_debugfs.c
@@ -98,8 +98,8 @@ minstrel_ht_stats_dump(struct minstrel_ht_sta *mi, int i, char *p)
 		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);
 
 		p += sprintf(p, "%4u.%1u    %4u.%1u     %3u.%1u"
 				"     %3u   %3u %-3u   "
@@ -243,8 +243,8 @@ minstrel_ht_stats_csv_dump(struct minstrel_ht_sta *mi, int i, char *p)
 		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);
 
 		p += sprintf(p, "%u.%u,%u.%u,%u.%u,%u,%u,"
 				"%u,%llu,%llu,",
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 1fa422782905..938c10f7955b 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -1617,7 +1617,7 @@ static bool ieee80211_queue_skb(struct ieee80211_local *local,
 
 static bool ieee80211_tx_frags(struct ieee80211_local *local,
 			       struct ieee80211_vif *vif,
-			       struct ieee80211_sta *sta,
+			       struct sta_info *sta,
 			       struct sk_buff_head *skbs,
 			       bool txpending)
 {
@@ -1679,7 +1679,7 @@ static bool ieee80211_tx_frags(struct ieee80211_local *local,
 		spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
 
 		info->control.vif = vif;
-		control.sta = sta;
+		control.sta = sta ? &sta->sta : NULL;
 
 		__skb_unlink(skb, skbs);
 		drv_tx(local, &control, skb);
@@ -1698,7 +1698,6 @@ static bool __ieee80211_tx(struct ieee80211_local *local,
 	struct ieee80211_tx_info *info;
 	struct ieee80211_sub_if_data *sdata;
 	struct ieee80211_vif *vif;
-	struct ieee80211_sta *pubsta;
 	struct sk_buff *skb;
 	bool result = true;
 	__le16 fc;
@@ -1713,11 +1712,6 @@ static bool __ieee80211_tx(struct ieee80211_local *local,
 	if (sta && !sta->uploaded)
 		sta = NULL;
 
-	if (sta)
-		pubsta = &sta->sta;
-	else
-		pubsta = NULL;
-
 	switch (sdata->vif.type) {
 	case NL80211_IFTYPE_MONITOR:
 		if (sdata->u.mntr.flags & MONITOR_FLAG_ACTIVE) {
@@ -1744,8 +1738,7 @@ static bool __ieee80211_tx(struct ieee80211_local *local,
 		break;
 	}
 
-	result = ieee80211_tx_frags(local, vif, pubsta, skbs,
-				    txpending);
+	result = ieee80211_tx_frags(local, vif, sta, skbs, txpending);
 
 	ieee80211_tpt_led_trig_tx(local, fc, led_len);
 
@@ -3529,7 +3522,7 @@ static bool ieee80211_xmit_fast(struct ieee80211_sub_if_data *sdata,
 				     struct ieee80211_sub_if_data, u.ap);
 
 	__skb_queue_tail(&tx.skbs, skb);
-	ieee80211_tx_frags(local, &sdata->vif, &sta->sta, &tx.skbs, false);
+	ieee80211_tx_frags(local, &sdata->vif, sta, &tx.skbs, false);
 	return true;
 }