Merge tag 'mac80211-next-for-net-next-2021-02-12' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next

Johannes Berg says:

====================
Last set of updates:
 * more minstrel work from Felix to reduce the
   probing overhead
 * QoS for nl80211 control port frames
 * STBC injection support
 * and a couple of small fixes
====================

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

10 files changed, 473 insertions, 425 deletions

diff --git a/net/mac80211/mesh_hwmp.c b/net/mac80211/mesh_hwmp.c
index 313eee12410e..3db514c4c63a 100644
--- a/net/mac80211/mesh_hwmp.c
+++ b/net/mac80211/mesh_hwmp.c
@@ -356,7 +356,7 @@ u32 airtime_link_metric_get(struct ieee80211_local *local,
 	 */
 	tx_time = (device_constant + 10 * test_frame_len / rate);
 	estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err));
-	result = (tx_time * estimated_retx) >> (2 * ARITH_SHIFT);
+	result = ((u64)tx_time * estimated_retx) >> (2 * ARITH_SHIFT);
 	return (u32)result;
 }
 
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 0e4d950cf907..2e33a1263518 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -5754,6 +5754,9 @@ int ieee80211_mgd_assoc(struct ieee80211_sub_if_data *sdata,
 	if (req->flags & ASSOC_REQ_DISABLE_VHT)
 		ifmgd->flags |= IEEE80211_STA_DISABLE_VHT;
 
+	if (req->flags & ASSOC_REQ_DISABLE_HE)
+		ifmgd->flags |= IEEE80211_STA_DISABLE_HE;
+
 	err = ieee80211_prep_connection(sdata, req->bss, true, override);
 	if (err)
 		goto err_clear;
diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c
index bfa550068de4..2f44f4919789 100644
--- a/net/mac80211/rc80211_minstrel_ht.c
+++ b/net/mac80211/rc80211_minstrel_ht.c
@@ -266,6 +266,14 @@ const struct mcs_group minstrel_mcs_groups[] = {
 const s16 minstrel_cck_bitrates[4] = { 10, 20, 55, 110 };
 const s16 minstrel_ofdm_bitrates[8] = { 60, 90, 120, 180, 240, 360, 480, 540 };
 static u8 sample_table[SAMPLE_COLUMNS][MCS_GROUP_RATES] __read_mostly;
+static const u8 minstrel_sample_seq[] = {
+	MINSTREL_SAMPLE_TYPE_INC,
+	MINSTREL_SAMPLE_TYPE_JUMP,
+	MINSTREL_SAMPLE_TYPE_INC,
+	MINSTREL_SAMPLE_TYPE_JUMP,
+	MINSTREL_SAMPLE_TYPE_INC,
+	MINSTREL_SAMPLE_TYPE_SLOW,
+};
 
 static void
 minstrel_ht_update_rates(struct minstrel_priv *mp, struct minstrel_ht_sta *mi);
@@ -379,13 +387,13 @@ out:
 static inline struct minstrel_rate_stats *
 minstrel_get_ratestats(struct minstrel_ht_sta *mi, int index)
 {
-	return &mi->groups[index / MCS_GROUP_RATES].rates[index % MCS_GROUP_RATES];
+	return &mi->groups[MI_RATE_GROUP(index)].rates[MI_RATE_IDX(index)];
 }
 
 static inline int minstrel_get_duration(int index)
 {
-	const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES];
-	unsigned int duration = group->duration[index % MCS_GROUP_RATES];
+	const struct mcs_group *group = &minstrel_mcs_groups[MI_RATE_GROUP(index)];
+	unsigned int duration = group->duration[MI_RATE_IDX(index)];
 
 	return duration << group->shift;
 }
@@ -398,7 +406,7 @@ minstrel_ht_avg_ampdu_len(struct minstrel_ht_sta *mi)
 	if (mi->avg_ampdu_len)
 		return MINSTREL_TRUNC(mi->avg_ampdu_len);
 
-	if (minstrel_ht_is_legacy_group(mi->max_tp_rate[0] / MCS_GROUP_RATES))
+	if (minstrel_ht_is_legacy_group(MI_RATE_GROUP(mi->max_tp_rate[0])))
 		return 1;
 
 	duration = minstrel_get_duration(mi->max_tp_rate[0]);
@@ -465,14 +473,14 @@ minstrel_ht_sort_best_tp_rates(struct minstrel_ht_sta *mi, u16 index,
 	int tmp_group, tmp_idx, tmp_tp_avg, tmp_prob;
 	int j = MAX_THR_RATES;
 
-	cur_group = index / MCS_GROUP_RATES;
-	cur_idx = index  % MCS_GROUP_RATES;
+	cur_group = MI_RATE_GROUP(index);
+	cur_idx = MI_RATE_IDX(index);
 	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_group = MI_RATE_GROUP(tp_list[j - 1]);
+		tmp_idx = MI_RATE_IDX(tp_list[j - 1]);
 		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);
@@ -504,23 +512,23 @@ minstrel_ht_set_best_prob_rate(struct minstrel_ht_sta *mi, u16 *dest, u16 index)
 	int max_gpr_group, max_gpr_idx;
 	int max_gpr_tp_avg, max_gpr_prob;
 
-	cur_group = index / MCS_GROUP_RATES;
-	cur_idx = index % MCS_GROUP_RATES;
-	mg = &mi->groups[index / MCS_GROUP_RATES];
-	mrs = &mg->rates[index % MCS_GROUP_RATES];
+	cur_group = MI_RATE_GROUP(index);
+	cur_idx = MI_RATE_IDX(index);
+	mg = &mi->groups[cur_group];
+	mrs = &mg->rates[cur_idx];
 
-	tmp_group = *dest / MCS_GROUP_RATES;
-	tmp_idx = *dest % MCS_GROUP_RATES;
+	tmp_group = MI_RATE_GROUP(*dest);
+	tmp_idx = MI_RATE_IDX(*dest);
 	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
 	 * MCS_GROUP as well as CCK_GROUP rates do not allow aggregation */
-	max_tp_group = mi->max_tp_rate[0] / MCS_GROUP_RATES;
-	max_tp_idx = mi->max_tp_rate[0] % MCS_GROUP_RATES;
+	max_tp_group = MI_RATE_GROUP(mi->max_tp_rate[0]);
+	max_tp_idx = MI_RATE_IDX(mi->max_tp_rate[0]);
 	max_tp_prob = mi->groups[max_tp_group].rates[max_tp_idx].prob_avg;
 
-	if (minstrel_ht_is_legacy_group(index / MCS_GROUP_RATES) &&
+	if (minstrel_ht_is_legacy_group(MI_RATE_GROUP(index)) &&
 	    !minstrel_ht_is_legacy_group(max_tp_group))
 		return;
 
@@ -529,8 +537,8 @@ minstrel_ht_set_best_prob_rate(struct minstrel_ht_sta *mi, u16 *dest, u16 index)
 	    mrs->prob_avg < max_tp_prob)
 		return;
 
-	max_gpr_group = mg->max_group_prob_rate / MCS_GROUP_RATES;
-	max_gpr_idx = mg->max_group_prob_rate % MCS_GROUP_RATES;
+	max_gpr_group = MI_RATE_GROUP(mg->max_group_prob_rate);
+	max_gpr_idx = MI_RATE_IDX(mg->max_group_prob_rate);
 	max_gpr_prob = mi->groups[max_gpr_group].rates[max_gpr_idx].prob_avg;
 
 	if (mrs->prob_avg > MINSTREL_FRAC(75, 100)) {
@@ -567,13 +575,13 @@ minstrel_ht_assign_best_tp_rates(struct minstrel_ht_sta *mi,
 	unsigned int tmp_group, tmp_idx, tmp_cck_tp, tmp_mcs_tp, tmp_prob;
 	int i;
 
-	tmp_group = tmp_legacy_tp_rate[0] / MCS_GROUP_RATES;
-	tmp_idx = tmp_legacy_tp_rate[0] % MCS_GROUP_RATES;
+	tmp_group = MI_RATE_GROUP(tmp_legacy_tp_rate[0]);
+	tmp_idx = MI_RATE_IDX(tmp_legacy_tp_rate[0]);
 	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_group = MI_RATE_GROUP(tmp_mcs_tp_rate[0]);
+	tmp_idx = MI_RATE_IDX(tmp_mcs_tp_rate[0]);
 	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);
 
@@ -600,14 +608,14 @@ minstrel_ht_prob_rate_reduce_streams(struct minstrel_ht_sta *mi)
 	if (!mi->sta->ht_cap.ht_supported)
 		return;
 
-	tmp_max_streams = minstrel_mcs_groups[mi->max_tp_rate[0] /
-			  MCS_GROUP_RATES].streams;
+	group = MI_RATE_GROUP(mi->max_tp_rate[0]);
+	tmp_max_streams = minstrel_mcs_groups[group].streams;
 	for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) {
 		mg = &mi->groups[group];
 		if (!mi->supported[group] || group == MINSTREL_CCK_GROUP)
 			continue;
 
-		tmp_idx = mg->max_group_prob_rate % MCS_GROUP_RATES;
+		tmp_idx = MI_RATE_IDX(mg->max_group_prob_rate);
 		tmp_prob = mi->groups[group].rates[tmp_idx].prob_avg;
 
 		if (tmp_tp < minstrel_ht_get_tp_avg(mi, group, tmp_idx, tmp_prob) &&
@@ -620,123 +628,24 @@ minstrel_ht_prob_rate_reduce_streams(struct minstrel_ht_sta *mi)
 	}
 }
 
-static bool
-minstrel_ht_probe_group(struct minstrel_ht_sta *mi, const struct mcs_group *tp_group,
-						int tp_idx, const struct mcs_group *group)
-{
-	if (group->bw < tp_group->bw)
-		return false;
-
-	if (group->streams == tp_group->streams)
-		return true;
-
-	if (tp_idx < 4 && group->streams == tp_group->streams - 1)
-		return true;
-
-	return group->streams == tp_group->streams + 1;
-}
-
-static void
-minstrel_ht_find_probe_rates(struct minstrel_ht_sta *mi, u16 *rates, int *n_rates,
-			     bool faster_rate)
-{
-	const struct mcs_group *group, *tp_group;
-	int i, g, max_dur;
-	int tp_idx;
-
-	tp_group = &minstrel_mcs_groups[mi->max_tp_rate[0] / MCS_GROUP_RATES];
-	tp_idx = mi->max_tp_rate[0] % MCS_GROUP_RATES;
-
-	max_dur = minstrel_get_duration(mi->max_tp_rate[0]);
-	if (faster_rate)
-		max_dur -= max_dur / 16;
-
-	for (g = 0; g < MINSTREL_GROUPS_NB; g++) {
-		u16 supported = mi->supported[g];
-
-		if (!supported)
-			continue;
-
-		group = &minstrel_mcs_groups[g];
-		if (!minstrel_ht_probe_group(mi, tp_group, tp_idx, group))
-			continue;
-
-		for (i = 0; supported; supported >>= 1, i++) {
-			int idx;
-
-			if (!(supported & 1))
-				continue;
-
-			if ((group->duration[i] << group->shift) > max_dur)
-				continue;
-
-			idx = g * MCS_GROUP_RATES + i;
-			if (idx == mi->max_tp_rate[0])
-				continue;
-
-			rates[(*n_rates)++] = idx;
-			break;
-		}
-	}
-}
-
-static void
-minstrel_ht_rate_sample_switch(struct minstrel_priv *mp,
-			       struct minstrel_ht_sta *mi)
+static u16
+__minstrel_ht_get_sample_rate(struct minstrel_ht_sta *mi,
+			      enum minstrel_sample_type type)
 {
-	struct minstrel_rate_stats *mrs;
-	u16 rates[MINSTREL_GROUPS_NB];
-	int n_rates = 0;
-	int probe_rate = 0;
-	bool faster_rate;
+	u16 *rates = mi->sample[type].sample_rates;
+	u16 cur;
 	int i;
-	u8 random;
 
-	/*
-	 * Use rate switching instead of probing packets for devices with
-	 * little control over retry fallback behavior
-	 */
-	if (mp->hw->max_rates > 1)
-		return;
-
-	/*
-	 * If the current EWMA prob is >75%, look for a rate that's 6.25%
-	 * faster than the max tp rate.
-	 * 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_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);
-
-	/* If no suitable rate was found, try to pick the next one in the group */
-	if (!n_rates) {
-		int g_idx = mi->max_tp_rate[0] / MCS_GROUP_RATES;
-		u16 supported = mi->supported[g_idx];
-
-		supported >>= mi->max_tp_rate[0] % MCS_GROUP_RATES;
-		for (i = 0; supported; supported >>= 1, i++) {
-			if (!(supported & 1))
-				continue;
-
-			probe_rate = mi->max_tp_rate[0] + i;
-			goto out;
-		}
-
-		return;
-	}
+	for (i = 0; i < MINSTREL_SAMPLE_RATES; i++) {
+		if (!rates[i])
+			continue;
 
-	i = 0;
-	if (n_rates > 1) {
-		random = prandom_u32();
-		i = random % n_rates;
+		cur = rates[i];
+		rates[i] = 0;
+		return cur;
 	}
-	probe_rate = rates[i];
 
-out:
-	mi->sample_rate = probe_rate;
-	mi->sample_mode = MINSTREL_SAMPLE_ACTIVE;
+	return 0;
 }
 
 static inline int
@@ -791,14 +700,11 @@ minstrel_ht_calc_rate_stats(struct minstrel_priv *mp,
 	unsigned int cur_prob;
 
 	if (unlikely(mrs->attempts > 0)) {
-		mrs->sample_skipped = 0;
 		cur_prob = MINSTREL_FRAC(mrs->success, mrs->attempts);
 		minstrel_filter_avg_add(&mrs->prob_avg,
 					&mrs->prob_avg_1, cur_prob);
 		mrs->att_hist += mrs->attempts;
 		mrs->succ_hist += mrs->success;
-	} else {
-		mrs->sample_skipped++;
 	}
 
 	mrs->last_success = mrs->success;
@@ -807,6 +713,274 @@ minstrel_ht_calc_rate_stats(struct minstrel_priv *mp,
 	mrs->attempts = 0;
 }
 
+static bool
+minstrel_ht_find_sample_rate(struct minstrel_ht_sta *mi, int type, int idx)
+{
+	int i;
+
+	for (i = 0; i < MINSTREL_SAMPLE_RATES; i++) {
+		u16 cur = mi->sample[type].sample_rates[i];
+
+		if (cur == idx)
+			return true;
+
+		if (!cur)
+			break;
+	}
+
+	return false;
+}
+
+static int
+minstrel_ht_move_sample_rates(struct minstrel_ht_sta *mi, int type,
+			      u32 fast_rate_dur, u32 slow_rate_dur)
+{
+	u16 *rates = mi->sample[type].sample_rates;
+	int i, j;
+
+	for (i = 0, j = 0; i < MINSTREL_SAMPLE_RATES; i++) {
+		u32 duration;
+		bool valid = false;
+		u16 cur;
+
+		cur = rates[i];
+		if (!cur)
+			continue;
+
+		duration = minstrel_get_duration(cur);
+		switch (type) {
+		case MINSTREL_SAMPLE_TYPE_SLOW:
+			valid = duration > fast_rate_dur &&
+				duration < slow_rate_dur;
+			break;
+		case MINSTREL_SAMPLE_TYPE_INC:
+		case MINSTREL_SAMPLE_TYPE_JUMP:
+			valid = duration < fast_rate_dur;
+			break;
+		default:
+			valid = false;
+			break;
+		}
+
+		if (!valid) {
+			rates[i] = 0;
+			continue;
+		}
+
+		if (i == j)
+			continue;
+
+		rates[j++] = cur;
+		rates[i] = 0;
+	}
+
+	return j;
+}
+
+static int
+minstrel_ht_group_min_rate_offset(struct minstrel_ht_sta *mi, int group,
+				  u32 max_duration)
+{
+	u16 supported = mi->supported[group];
+	int i;
+
+	for (i = 0; i < MCS_GROUP_RATES && supported; i++, supported >>= 1) {
+		if (!(supported & BIT(0)))
+			continue;
+
+		if (minstrel_get_duration(MI_RATE(group, i)) >= max_duration)
+			continue;
+
+		return i;
+	}
+
+	return -1;
+}
+
+/*
+ * Incremental update rates:
+ * Flip through groups and pick the first group rate that is faster than the
+ * highest currently selected rate
+ */
+static u16
+minstrel_ht_next_inc_rate(struct minstrel_ht_sta *mi, u32 fast_rate_dur)
+{
+	struct minstrel_mcs_group_data *mg;
+	u8 type = MINSTREL_SAMPLE_TYPE_INC;
+	int i, index = 0;
+	u8 group;
+
+	group = mi->sample[type].sample_group;
+	for (i = 0; i < ARRAY_SIZE(minstrel_mcs_groups); i++) {
+		group = (group + 1) % ARRAY_SIZE(minstrel_mcs_groups);
+		mg = &mi->groups[group];
+
+		index = minstrel_ht_group_min_rate_offset(mi, group,
+							  fast_rate_dur);
+		if (index < 0)
+			continue;
+
+		index = MI_RATE(group, index & 0xf);
+		if (!minstrel_ht_find_sample_rate(mi, type, index))
+			goto out;
+	}
+	index = 0;
+
+out:
+	mi->sample[type].sample_group = group;
+
+	return index;
+}
+
+static int
+minstrel_ht_next_group_sample_rate(struct minstrel_ht_sta *mi, int group,
+				   u16 supported, int offset)
+{
+	struct minstrel_mcs_group_data *mg = &mi->groups[group];
+	u16 idx;
+	int i;
+
+	for (i = 0; i < MCS_GROUP_RATES; i++) {
+		idx = sample_table[mg->column][mg->index];
+		if (++mg->index >= MCS_GROUP_RATES) {
+			mg->index = 0;
+			if (++mg->column >= ARRAY_SIZE(sample_table))
+				mg->column = 0;
+		}
+
+		if (idx < offset)
+			continue;
+
+		if (!(supported & BIT(idx)))
+			continue;
+
+		return MI_RATE(group, idx);
+	}
+
+	return -1;
+}
+
+/*
+ * Jump rates:
+ * Sample random rates, use those that are faster than the highest
+ * currently selected rate. Rates between the fastest and the slowest
+ * get sorted into the slow sample bucket, but only if it has room
+ */
+static u16
+minstrel_ht_next_jump_rate(struct minstrel_ht_sta *mi, u32 fast_rate_dur,
+			   u32 slow_rate_dur, int *slow_rate_ofs)
+{
+	struct minstrel_mcs_group_data *mg;
+	struct minstrel_rate_stats *mrs;
+	u32 max_duration = slow_rate_dur;
+	int i, index, offset;
+	u16 *slow_rates;
+	u16 supported;
+	u32 duration;
+	u8 group;
+
+	if (*slow_rate_ofs >= MINSTREL_SAMPLE_RATES)
+		max_duration = fast_rate_dur;
+
+	slow_rates = mi->sample[MINSTREL_SAMPLE_TYPE_SLOW].sample_rates;
+	group = mi->sample[MINSTREL_SAMPLE_TYPE_JUMP].sample_group;
+	for (i = 0; i < ARRAY_SIZE(minstrel_mcs_groups); i++) {
+		u8 type;
+
+		group = (group + 1) % ARRAY_SIZE(minstrel_mcs_groups);
+		mg = &mi->groups[group];
+
+		supported = mi->supported[group];
+		if (!supported)
+			continue;
+
+		offset = minstrel_ht_group_min_rate_offset(mi, group,
+							   max_duration);
+		if (offset < 0)
+			continue;
+
+		index = minstrel_ht_next_group_sample_rate(mi, group, supported,
+							   offset);
+		if (index < 0)
+			continue;
+
+		duration = minstrel_get_duration(index);
+		if (duration < fast_rate_dur)
+			type = MINSTREL_SAMPLE_TYPE_JUMP;
+		else
+			type = MINSTREL_SAMPLE_TYPE_SLOW;
+
+		if (minstrel_ht_find_sample_rate(mi, type, index))
+			continue;
+
+		if (type == MINSTREL_SAMPLE_TYPE_JUMP)
+			goto found;
+
+		if (*slow_rate_ofs >= MINSTREL_SAMPLE_RATES)
+			continue;
+
+		if (duration >= slow_rate_dur)
+			continue;
+
+		/* skip slow rates with high success probability */
+		mrs = minstrel_get_ratestats(mi, index);
+		if (mrs->prob_avg > MINSTREL_FRAC(95, 100))
+			continue;
+
+		slow_rates[(*slow_rate_ofs)++] = index;
+		if (*slow_rate_ofs >= MINSTREL_SAMPLE_RATES)
+			max_duration = fast_rate_dur;
+	}
+	index = 0;
+
+found:
+	mi->sample[MINSTREL_SAMPLE_TYPE_JUMP].sample_group = group;
+
+	return index;
+}
+
+static void
+minstrel_ht_refill_sample_rates(struct minstrel_ht_sta *mi)
+{
+	u32 prob_dur = minstrel_get_duration(mi->max_prob_rate);
+	u32 tp_dur = minstrel_get_duration(mi->max_tp_rate[0]);
+	u32 tp2_dur = minstrel_get_duration(mi->max_tp_rate[1]);
+	u32 fast_rate_dur = min(min(tp_dur, tp2_dur), prob_dur);
+	u32 slow_rate_dur = max(max(tp_dur, tp2_dur), prob_dur);
+	u16 *rates;
+	int i, j;
+
+	rates = mi->sample[MINSTREL_SAMPLE_TYPE_INC].sample_rates;
+	i = minstrel_ht_move_sample_rates(mi, MINSTREL_SAMPLE_TYPE_INC,
+					  fast_rate_dur, slow_rate_dur);
+	while (i < MINSTREL_SAMPLE_RATES) {
+		rates[i] = minstrel_ht_next_inc_rate(mi, tp_dur);
+		if (!rates[i])
+			break;
+
+		i++;
+	}
+
+	rates = mi->sample[MINSTREL_SAMPLE_TYPE_JUMP].sample_rates;
+	i = minstrel_ht_move_sample_rates(mi, MINSTREL_SAMPLE_TYPE_JUMP,
+					  fast_rate_dur, slow_rate_dur);
+	j = minstrel_ht_move_sample_rates(mi, MINSTREL_SAMPLE_TYPE_SLOW,
+					  fast_rate_dur, slow_rate_dur);
+	while (i < MINSTREL_SAMPLE_RATES) {
+		rates[i] = minstrel_ht_next_jump_rate(mi, fast_rate_dur,
+						      slow_rate_dur, &j);
+		if (!rates[i])
+			break;
+
+		i++;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(mi->sample); i++)
+		memcpy(mi->sample[i].cur_sample_rates, mi->sample[i].sample_rates,
+		       sizeof(mi->sample[i].cur_sample_rates));
+}
+
+
 /*
  * Update rate statistics and select new primary rates
  *
@@ -817,8 +991,7 @@ minstrel_ht_calc_rate_stats(struct minstrel_priv *mp,
  *    higher throughput rates, even if the probablity is a bit lower
  */
 static void
-minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
-			 bool sample)
+minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
 {
 	struct minstrel_mcs_group_data *mg;
 	struct minstrel_rate_stats *mrs;
@@ -828,18 +1001,6 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
 	u16 index;
 	bool ht_supported = mi->sta->ht_cap.ht_supported;
 
-	mi->sample_mode = MINSTREL_SAMPLE_IDLE;
-
-	if (sample) {
-		mi->total_packets_cur = mi->total_packets -
-					mi->total_packets_last;
-		mi->total_packets_last = mi->total_packets;
-	}
-	if (!mp->sample_switch)
-		sample = false;
-	if (mi->total_packets_cur < SAMPLE_SWITCH_THR && mp->sample_switch != 1)
-	    sample = false;
-
 	if (mi->ampdu_packets > 0) {
 		if (!ieee80211_hw_check(mp->hw, TX_STATUS_NO_AMPDU_LEN))
 			mi->avg_ampdu_len = minstrel_ewma(mi->avg_ampdu_len,
@@ -851,27 +1012,27 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
 		mi->ampdu_packets = 0;
 	}
 
-	mi->sample_slow = 0;
-	mi->sample_count = 0;
-
-	memset(tmp_mcs_tp_rate, 0, sizeof(tmp_mcs_tp_rate));
-	memset(tmp_legacy_tp_rate, 0, sizeof(tmp_legacy_tp_rate));
 	if (mi->supported[MINSTREL_CCK_GROUP])
-		for (j = 0; j < ARRAY_SIZE(tmp_legacy_tp_rate); j++)
-			tmp_legacy_tp_rate[j] = MINSTREL_CCK_GROUP * MCS_GROUP_RATES;
+		group = MINSTREL_CCK_GROUP;
 	else if (mi->supported[MINSTREL_OFDM_GROUP])
-		for (j = 0; j < ARRAY_SIZE(tmp_legacy_tp_rate); j++)
-			tmp_legacy_tp_rate[j] = MINSTREL_OFDM_GROUP * MCS_GROUP_RATES;
+		group = MINSTREL_OFDM_GROUP;
+	else
+		group = 0;
+
+	index = MI_RATE(group, 0);
+	for (j = 0; j < ARRAY_SIZE(tmp_legacy_tp_rate); j++)
+		tmp_legacy_tp_rate[j] = index;
 
 	if (mi->supported[MINSTREL_VHT_GROUP_0])
-		index = MINSTREL_VHT_GROUP_0 * MCS_GROUP_RATES;
+		group = MINSTREL_VHT_GROUP_0;
 	else if (ht_supported)
-		index = MINSTREL_HT_GROUP_0 * MCS_GROUP_RATES;
+		group = MINSTREL_HT_GROUP_0;
 	else if (mi->supported[MINSTREL_CCK_GROUP])
-		index = MINSTREL_CCK_GROUP * MCS_GROUP_RATES;
+		group = MINSTREL_CCK_GROUP;
 	else
-		index = MINSTREL_OFDM_GROUP * MCS_GROUP_RATES;
+		group = MINSTREL_OFDM_GROUP;
 
+	index = MI_RATE(group, 0);
 	tmp_max_prob_rate = index;
 	for (j = 0; j < ARRAY_SIZE(tmp_mcs_tp_rate); j++)
 		tmp_mcs_tp_rate[j] = index;
@@ -879,29 +1040,33 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
 	/* Find best rate sets within all MCS groups*/
 	for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) {
 		u16 *tp_rate = tmp_mcs_tp_rate;
+		u16 last_prob = 0;
 
 		mg = &mi->groups[group];
 		if (!mi->supported[group])
 			continue;
 
-		mi->sample_count++;
-
 		/* (re)Initialize group rate indexes */
 		for(j = 0; j < MAX_THR_RATES; j++)
-			tmp_group_tp_rate[j] = MCS_GROUP_RATES * group;
+			tmp_group_tp_rate[j] = MI_RATE(group, 0);
 
 		if (group == MINSTREL_CCK_GROUP && ht_supported)
 			tp_rate = tmp_legacy_tp_rate;
 
-		for (i = 0; i < MCS_GROUP_RATES; i++) {
+		for (i = MCS_GROUP_RATES - 1; i >= 0; i--) {
 			if (!(mi->supported[group] & BIT(i)))
 				continue;
 
-			index = MCS_GROUP_RATES * group + i;
+			index = MI_RATE(group, i);
 
 			mrs = &mg->rates[i];
 			mrs->retry_updated = false;
 			minstrel_ht_calc_rate_stats(mp, mrs);
+
+			if (mrs->att_hist)
+				last_prob = max(last_prob, mrs->prob_avg);
+			else
+				mrs->prob_avg = max(last_prob, mrs->prob_avg);
 			cur_prob = mrs->prob_avg;
 
 			if (minstrel_ht_get_tp_avg(mi, group, i, cur_prob) == 0)
@@ -929,13 +1094,13 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
 			continue;
 
 		mg = &mi->groups[group];
-		mg->max_group_prob_rate = MCS_GROUP_RATES * group;
+		mg->max_group_prob_rate = MI_RATE(group, 0);
 
 		for (i = 0; i < MCS_GROUP_RATES; i++) {
 			if (!(mi->supported[group] & BIT(i)))
 				continue;
 
-			index = MCS_GROUP_RATES * group + i;
+			index = MI_RATE(group, i);
 
 			/* Find max probability rate per group and global */
 			minstrel_ht_set_best_prob_rate(mi, &tmp_max_prob_rate,
@@ -947,12 +1112,7 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
 
 	/* Try to increase robustness of max_prob_rate*/
 	minstrel_ht_prob_rate_reduce_streams(mi);
-
-	/* try to sample half of all available rates during each interval */
-	mi->sample_count *= 4;
-
-	if (sample)
-		minstrel_ht_rate_sample_switch(mp, mi);
+	minstrel_ht_refill_sample_rates(mi);
 
 #ifdef CONFIG_MAC80211_DEBUGFS
 	/* use fixed index if set */
@@ -960,12 +1120,12 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
 		for (i = 0; i < 4; i++)
 			mi->max_tp_rate[i] = mp->fixed_rate_idx;
 		mi->max_prob_rate = mp->fixed_rate_idx;
-		mi->sample_mode = MINSTREL_SAMPLE_IDLE;
 	}
 #endif
 
 	/* Reset update timer */
 	mi->last_stats_update = jiffies;
+	mi->sample_time = jiffies;
 }
 
 static bool
@@ -996,33 +1156,11 @@ minstrel_ht_txstat_valid(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
 }
 
 static void
-minstrel_set_next_sample_idx(struct minstrel_ht_sta *mi)
-{
-	struct minstrel_mcs_group_data *mg;
-
-	for (;;) {
-		mi->sample_group++;
-		mi->sample_group %= ARRAY_SIZE(minstrel_mcs_groups);
-		mg = &mi->groups[mi->sample_group];
-
-		if (!mi->supported[mi->sample_group])
-			continue;
-
-		if (++mg->index >= MCS_GROUP_RATES) {
-			mg->index = 0;
-			if (++mg->column >= ARRAY_SIZE(sample_table))
-				mg->column = 0;
-		}
-		break;
-	}
-}
-
-static void
 minstrel_downgrade_rate(struct minstrel_ht_sta *mi, u16 *idx, bool primary)
 {
 	int group, orig_group;
 
-	orig_group = group = *idx / MCS_GROUP_RATES;
+	orig_group = group = MI_RATE_GROUP(*idx);
 	while (group > 0) {
 		group--;
 
@@ -1071,11 +1209,10 @@ minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband,
 	struct ieee80211_tx_info *info = st->info;
 	struct minstrel_ht_sta *mi = priv_sta;
 	struct ieee80211_tx_rate *ar = info->status.rates;
-	struct minstrel_rate_stats *rate, *rate2, *rate_sample = NULL;
+	struct minstrel_rate_stats *rate, *rate2;
 	struct minstrel_priv *mp = priv;
 	u32 update_interval = mp->update_interval;
 	bool last, update = false;
-	bool sample_status = false;
 	int i;
 
 	/* This packet was aggregated but doesn't carry status info */
@@ -1089,22 +1226,18 @@ minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband,
 		info->status.ampdu_len = 1;
 	}
 
-	mi->ampdu_packets++;
-	mi->ampdu_len += info->status.ampdu_len;
-
-	if (!mi->sample_wait && !mi->sample_tries && mi->sample_count > 0) {
-		int avg_ampdu_len = minstrel_ht_avg_ampdu_len(mi);
-
-		mi->sample_wait = 16 + 2 * avg_ampdu_len;
-		mi->sample_tries = 1;
-		mi->sample_count--;
+	/* wraparound */
+	if (mi->total_packets >= ~0 - info->status.ampdu_len) {
+		mi->total_packets = 0;
+		mi->sample_packets = 0;
 	}
 
+	mi->total_packets += info->status.ampdu_len;
 	if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE)
 		mi->sample_packets += info->status.ampdu_len;
 
-	if (mi->sample_mode != MINSTREL_SAMPLE_IDLE)
-		rate_sample = minstrel_get_ratestats(mi, mi->sample_rate);
+	mi->ampdu_packets++;
+	mi->ampdu_len += info->status.ampdu_len;
 
 	last = !minstrel_ht_txstat_valid(mp, mi, &ar[0]);
 	for (i = 0; !last; i++) {
@@ -1112,40 +1245,12 @@ minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband,
 		       !minstrel_ht_txstat_valid(mp, mi, &ar[i + 1]);
 
 		rate = minstrel_ht_get_stats(mp, mi, &ar[i]);
-		if (rate == rate_sample)
-			sample_status = true;
-
 		if (last)
 			rate->success += info->status.ampdu_ack_len;
 
 		rate->attempts += ar[i].count * info->status.ampdu_len;
 	}
 
-	switch (mi->sample_mode) {
-	case MINSTREL_SAMPLE_IDLE:
-		if (mp->hw->max_rates > 1 ||
-		     mi->total_packets_cur < SAMPLE_SWITCH_THR)
-			update_interval /= 2;
-		break;
-
-	case MINSTREL_SAMPLE_ACTIVE:
-		if (!sample_status)
-			break;
-
-		mi->sample_mode = MINSTREL_SAMPLE_PENDING;
-		update = true;
-		break;
-
-	case MINSTREL_SAMPLE_PENDING:
-		if (sample_status)
-			break;
-
-		update = true;
-		minstrel_ht_update_stats(mp, mi, false);
-		break;
-	}
-
-
 	if (mp->hw->max_rates > 1) {
 		/*
 		 * check for sudden death of spatial multiplexing,
@@ -1168,7 +1273,7 @@ minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband,
 
 	if (time_after(jiffies, mi->last_stats_update + update_interval)) {
 		update = true;
-		minstrel_ht_update_stats(mp, mi, true);
+		minstrel_ht_update_stats(mp, mi);
 	}
 
 	if (update)
@@ -1206,7 +1311,7 @@ minstrel_calc_retransmit(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
 	ctime += (t_slot * cw) >> 1;
 	cw = min((cw << 1) | 1, mp->cw_max);
 
-	if (minstrel_ht_is_legacy_group(index / MCS_GROUP_RATES)) {
+	if (minstrel_ht_is_legacy_group(MI_RATE_GROUP(index))) {
 		overhead = mi->overhead_legacy;
 		overhead_rtscts = mi->overhead_legacy_rtscts;
 	} else {
@@ -1239,7 +1344,7 @@ static void
 minstrel_ht_set_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
                      struct ieee80211_sta_rates *ratetbl, int offset, int index)
 {
-	int group_idx = index / MCS_GROUP_RATES;
+	int group_idx = MI_RATE_GROUP(index);
 	const struct mcs_group *group = &minstrel_mcs_groups[group_idx];
 	struct minstrel_rate_stats *mrs;
 	u8 idx;
@@ -1259,7 +1364,7 @@ minstrel_ht_set_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
 		ratetbl->rate[offset].count_rts = mrs->retry_count_rtscts;
 	}
 
-	index %= MCS_GROUP_RATES;
+	index = MI_RATE_IDX(index);
 	if (group_idx == MINSTREL_CCK_GROUP)
 		idx = mp->cck_rates[index % ARRAY_SIZE(mp->cck_rates)];
 	else if (group_idx == MINSTREL_OFDM_GROUP)
@@ -1289,17 +1394,17 @@ minstrel_ht_set_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
 static inline int
 minstrel_ht_get_prob_avg(struct minstrel_ht_sta *mi, int rate)
 {
-	int group = rate / MCS_GROUP_RATES;
-	rate %= MCS_GROUP_RATES;
+	int group = MI_RATE_GROUP(rate);
+	rate = MI_RATE_IDX(rate);
 	return mi->groups[group].rates[rate].prob_avg;
 }
 
 static int
 minstrel_ht_get_max_amsdu_len(struct minstrel_ht_sta *mi)
 {
-	int group = mi->max_prob_rate / MCS_GROUP_RATES;
+	int group = MI_RATE_GROUP(mi->max_prob_rate);
 	const struct mcs_group *g = &minstrel_mcs_groups[group];
-	int rate = mi->max_prob_rate % MCS_GROUP_RATES;
+	int rate = MI_RATE_IDX(mi->max_prob_rate);
 	unsigned int duration;
 
 	/* Disable A-MSDU if max_prob_rate is bad */
@@ -1347,18 +1452,14 @@ static void
 minstrel_ht_update_rates(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
 {
 	struct ieee80211_sta_rates *rates;
-	u16 first_rate = mi->max_tp_rate[0];
 	int i = 0;
 
-	if (mi->sample_mode == MINSTREL_SAMPLE_ACTIVE)
-		first_rate = mi->sample_rate;
-
 	rates = kzalloc(sizeof(*rates), GFP_ATOMIC);
 	if (!rates)
 		return;
 
 	/* Start with max_tp_rate[0] */
-	minstrel_ht_set_rate(mp, mi, rates, i++, first_rate);
+	minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_tp_rate[0]);
 
 	if (mp->hw->max_rates >= 3) {
 		/* At least 3 tx rates supported, use max_tp_rate[1] next */
@@ -1374,102 +1475,20 @@ minstrel_ht_update_rates(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
 	rate_control_set_rates(mp->hw, mi->sta, rates);
 }
 
-static int
-minstrel_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
+static u16
+minstrel_ht_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
 {
-	struct minstrel_rate_stats *mrs;
-	struct minstrel_mcs_group_data *mg;
-	unsigned int sample_dur, sample_group, cur_max_tp_streams;
-	int tp_rate1, tp_rate2;
-	int sample_idx = 0;
-
-	if (mp->hw->max_rates == 1 && mp->sample_switch &&
-	    (mi->total_packets_cur >= SAMPLE_SWITCH_THR ||
-	     mp->sample_switch == 1))
-		return -1;
-
-	if (mi->sample_wait > 0) {
-		mi->sample_wait--;
-		return -1;
-	}
-
-	if (!mi->sample_tries)
-		retu