--- /dev/null
+From: Felix Fietkau <nbd@nbd.name>
+Date: Wed, 14 Dec 2016 19:33:23 +0100
+Subject: [PATCH] mac80211: minstrel_ht: move supported bitrate mask out of
+ group data
+
+Improves dcache footprint by ensuring that fewer cache lines need to be
+touched.
+
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+---
+
+--- a/net/mac80211/rc80211_minstrel_ht.c
++++ b/net/mac80211/rc80211_minstrel_ht.c
+@@ -301,7 +301,7 @@ minstrel_ht_get_stats(struct minstrel_pr
+ break;
+
+ /* short preamble */
+- if (!(mi->groups[group].supported & BIT(idx)))
++ if (!(mi->supported[group] & BIT(idx)))
+ idx += 4;
+ }
+ return &mi->groups[group].rates[idx];
+@@ -486,7 +486,7 @@ minstrel_ht_prob_rate_reduce_streams(str
+ MCS_GROUP_RATES].streams;
+ for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) {
+ mg = &mi->groups[group];
+- if (!mg->supported || group == MINSTREL_CCK_GROUP)
++ if (!mi->supported[group] || group == MINSTREL_CCK_GROUP)
+ continue;
+
+ tmp_idx = mg->max_group_prob_rate % MCS_GROUP_RATES;
+@@ -540,7 +540,7 @@ minstrel_ht_update_stats(struct minstrel
+ for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) {
+
+ mg = &mi->groups[group];
+- if (!mg->supported)
++ if (!mi->supported[group])
+ continue;
+
+ mi->sample_count++;
+@@ -550,7 +550,7 @@ minstrel_ht_update_stats(struct minstrel
+ tmp_group_tp_rate[j] = group;
+
+ for (i = 0; i < MCS_GROUP_RATES; i++) {
+- if (!(mg->supported & BIT(i)))
++ if (!(mi->supported[group] & BIT(i)))
+ continue;
+
+ index = MCS_GROUP_RATES * group + i;
+@@ -636,7 +636,7 @@ minstrel_set_next_sample_idx(struct mins
+ mi->sample_group %= ARRAY_SIZE(minstrel_mcs_groups);
+ mg = &mi->groups[mi->sample_group];
+
+- if (!mg->supported)
++ if (!mi->supported[mi->sample_group])
+ continue;
+
+ if (++mg->index >= MCS_GROUP_RATES) {
+@@ -657,7 +657,7 @@ minstrel_downgrade_rate(struct minstrel_
+ while (group > 0) {
+ group--;
+
+- if (!mi->groups[group].supported)
++ if (!mi->supported[group])
+ continue;
+
+ if (minstrel_mcs_groups[group].streams >
+@@ -994,7 +994,7 @@ minstrel_get_sample_rate(struct minstrel
+ sample_idx = sample_table[mg->column][mg->index];
+ minstrel_set_next_sample_idx(mi);
+
+- if (!(mg->supported & BIT(sample_idx)))
++ if (!(mi->supported[sample_group] & BIT(sample_idx)))
+ return -1;
+
+ mrs = &mg->rates[sample_idx];
+@@ -1052,7 +1052,7 @@ static void
+ minstrel_ht_check_cck_shortpreamble(struct minstrel_priv *mp,
+ struct minstrel_ht_sta *mi, bool val)
+ {
+- u8 supported = mi->groups[MINSTREL_CCK_GROUP].supported;
++ u8 supported = mi->supported[MINSTREL_CCK_GROUP];
+
+ if (!supported || !mi->cck_supported_short)
+ return;
+@@ -1061,7 +1061,7 @@ minstrel_ht_check_cck_shortpreamble(stru
+ return;
+
+ supported ^= mi->cck_supported_short | (mi->cck_supported_short << 4);
+- mi->groups[MINSTREL_CCK_GROUP].supported = supported;
++ mi->supported[MINSTREL_CCK_GROUP] = supported;
+ }
+
+ static void
+@@ -1154,7 +1154,7 @@ minstrel_ht_update_cck(struct minstrel_p
+ mi->cck_supported_short |= BIT(i);
+ }
+
+- mi->groups[MINSTREL_CCK_GROUP].supported = mi->cck_supported;
++ mi->supported[MINSTREL_CCK_GROUP] = mi->cck_supported;
+ }
+
+ static void
+@@ -1233,7 +1233,7 @@ minstrel_ht_update_caps(void *priv, stru
+ u32 gflags = minstrel_mcs_groups[i].flags;
+ int bw, nss;
+
+- mi->groups[i].supported = 0;
++ mi->supported[i] = 0;
+ if (i == MINSTREL_CCK_GROUP) {
+ minstrel_ht_update_cck(mp, mi, sband, sta);
+ continue;
+@@ -1265,8 +1265,8 @@ minstrel_ht_update_caps(void *priv, stru
+ if (use_vht && minstrel_vht_only)
+ continue;
+ #endif
+- mi->groups[i].supported = mcs->rx_mask[nss - 1];
+- if (mi->groups[i].supported)
++ mi->supported[i] = mcs->rx_mask[nss - 1];
++ if (mi->supported[i])
+ n_supported++;
+ continue;
+ }
+@@ -1292,10 +1292,10 @@ minstrel_ht_update_caps(void *priv, stru
+ else
+ bw = BW_20;
+
+- mi->groups[i].supported = minstrel_get_valid_vht_rates(bw, nss,
++ mi->supported[i] = minstrel_get_valid_vht_rates(bw, nss,
+ vht_cap->vht_mcs.tx_mcs_map);
+
+- if (mi->groups[i].supported)
++ if (mi->supported[i])
+ n_supported++;
+ }
+
+--- a/net/mac80211/rc80211_minstrel_ht.h
++++ b/net/mac80211/rc80211_minstrel_ht.h
+@@ -52,9 +52,6 @@ struct minstrel_mcs_group_data {
+ u8 index;
+ u8 column;
+
+- /* bitfield of supported MCS rates of this group */
+- u16 supported;
+-
+ /* sorted rate set within a MCS group*/
+ u16 max_group_tp_rate[MAX_THR_RATES];
+ u16 max_group_prob_rate;
+@@ -101,6 +98,9 @@ struct minstrel_ht_sta {
+ u8 cck_supported;
+ u8 cck_supported_short;
+
++ /* Bitfield of supported MCS rates of all groups */
++ u16 supported[MINSTREL_GROUPS_NB];
++
+ /* MCS rate group info and statistics */
+ struct minstrel_mcs_group_data groups[MINSTREL_GROUPS_NB];
+ };
+--- a/net/mac80211/rc80211_minstrel_ht_debugfs.c
++++ b/net/mac80211/rc80211_minstrel_ht_debugfs.c
+@@ -24,7 +24,7 @@ minstrel_ht_stats_dump(struct minstrel_h
+ char gimode = 'L';
+ u32 gflags;
+
+- if (!mi->groups[i].supported)
++ if (!mi->supported[i])
+ return p;
+
+ mg = &minstrel_mcs_groups[i];
+@@ -42,7 +42,7 @@ minstrel_ht_stats_dump(struct minstrel_h
+ static const int bitrates[4] = { 10, 20, 55, 110 };
+ int idx = i * MCS_GROUP_RATES + j;
+
+- if (!(mi->groups[i].supported & BIT(j)))
++ if (!(mi->supported[i] & BIT(j)))
+ continue;
+
+ if (gflags & IEEE80211_TX_RC_MCS) {
+@@ -170,7 +170,7 @@ minstrel_ht_stats_csv_dump(struct minstr
+ char gimode = 'L';
+ u32 gflags;
+
+- if (!mi->groups[i].supported)
++ if (!mi->supported[i])
+ return p;
+
+ mg = &minstrel_mcs_groups[i];
+@@ -188,7 +188,7 @@ minstrel_ht_stats_csv_dump(struct minstr
+ static const int bitrates[4] = { 10, 20, 55, 110 };
+ int idx = i * MCS_GROUP_RATES + j;
+
+- if (!(mi->groups[i].supported & BIT(j)))
++ if (!(mi->supported[i] & BIT(j)))
+ continue;
+
+ if (gflags & IEEE80211_TX_RC_MCS) {
--- /dev/null
+From: Felix Fietkau <nbd@nbd.name>
+Date: Wed, 14 Dec 2016 20:06:08 +0100
+Subject: [PATCH] mac80211: minstrel_ht: move short preamble check out of
+ get_rate
+
+Test short preamble support in minstrel_ht_update_caps instead of
+looking at the per-packet flag. Makes the code more efficient.
+
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+---
+
+--- a/net/mac80211/rc80211_minstrel_ht.c
++++ b/net/mac80211/rc80211_minstrel_ht.c
+@@ -14,6 +14,7 @@
+ #include <linux/ieee80211.h>
+ #include <net/mac80211.h>
+ #include "rate.h"
++#include "sta_info.h"
+ #include "rc80211_minstrel.h"
+ #include "rc80211_minstrel_ht.h"
+
+@@ -1049,22 +1050,6 @@ minstrel_get_sample_rate(struct minstrel
+ }
+
+ static void
+-minstrel_ht_check_cck_shortpreamble(struct minstrel_priv *mp,
+- struct minstrel_ht_sta *mi, bool val)
+-{
+- u8 supported = mi->supported[MINSTREL_CCK_GROUP];
+-
+- if (!supported || !mi->cck_supported_short)
+- return;
+-
+- if (supported & (mi->cck_supported_short << (val * 4)))
+- return;
+-
+- supported ^= mi->cck_supported_short | (mi->cck_supported_short << 4);
+- mi->supported[MINSTREL_CCK_GROUP] = supported;
+-}
+-
+-static void
+ minstrel_ht_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta,
+ struct ieee80211_tx_rate_control *txrc)
+ {
+@@ -1087,7 +1072,6 @@ minstrel_ht_get_rate(void *priv, struct
+ minstrel_aggr_check(sta, txrc->skb);
+
+ info->flags |= mi->tx_flags;
+- minstrel_ht_check_cck_shortpreamble(mp, mi, txrc->short_preamble);
+
+ #ifdef CPTCFG_MAC80211_DEBUGFS
+ if (mp->fixed_rate_idx != -1)
+@@ -1168,6 +1152,7 @@ minstrel_ht_update_caps(void *priv, stru
+ struct ieee80211_mcs_info *mcs = &sta->ht_cap.mcs;
+ u16 ht_cap = sta->ht_cap.cap;
+ struct ieee80211_sta_vht_cap *vht_cap = &sta->vht_cap;
++ struct sta_info *sinfo = container_of(sta, struct sta_info, sta);
+ int use_vht;
+ int n_supported = 0;
+ int ack_dur;
+@@ -1302,6 +1287,9 @@ minstrel_ht_update_caps(void *priv, stru
+ if (!n_supported)
+ goto use_legacy;
+
++ if (test_sta_flag(sinfo, WLAN_STA_SHORT_PREAMBLE))
++ mi->cck_supported_short |= mi->cck_supported_short << 4;
++
+ /* create an initial rate table with the lowest supported rates */
+ minstrel_ht_update_stats(mp, mi);
+ minstrel_ht_update_rates(mp, mi);
--- /dev/null
+From: Felix Fietkau <nbd@nbd.name>
+Date: Wed, 14 Dec 2016 20:09:14 +0100
+Subject: [PATCH] mac80211: minstrel_ht: make att_hist and succ_hist u32
+ instead of u64
+
+They are only used for debugging purposes and take a very long time to
+overflow. Visibly reduces the size of the per-sta rate control data.
+
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+---
+
+--- a/net/mac80211/rc80211_minstrel.h
++++ b/net/mac80211/rc80211_minstrel.h
+@@ -59,7 +59,7 @@ struct minstrel_rate_stats {
+ u16 success, last_success;
+
+ /* total attempts/success counters */
+- u64 att_hist, succ_hist;
++ u32 att_hist, succ_hist;
+
+ /* statistis of packet delivery probability
+ * cur_prob - current prob within last update intervall
--- /dev/null
+From: Felix Fietkau <nbd@nbd.name>
+Date: Wed, 14 Dec 2016 20:12:25 +0100
+Subject: [PATCH] mac80211: check for MCS in ieee80211_duration before fetching
+ chanctx
+
+Makes the code a bit more efficient
+
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+---
+
+--- a/net/mac80211/tx.c
++++ b/net/mac80211/tx.c
+@@ -63,6 +63,10 @@ static __le16 ieee80211_duration(struct
+ struct ieee80211_chanctx_conf *chanctx_conf;
+ u32 rate_flags = 0;
+
++ /* assume HW handles this */
++ if (tx->rate.flags & (IEEE80211_TX_RC_MCS | IEEE80211_TX_RC_VHT_MCS))
++ return 0;
++
+ rcu_read_lock();
+ chanctx_conf = rcu_dereference(tx->sdata->vif.chanctx_conf);
+ if (chanctx_conf) {
+@@ -71,10 +75,6 @@ static __le16 ieee80211_duration(struct
+ }
+ rcu_read_unlock();
+
+- /* assume HW handles this */
+- if (tx->rate.flags & (IEEE80211_TX_RC_MCS | IEEE80211_TX_RC_VHT_MCS))
+- return 0;
+-
+ /* uh huh? */
+ if (WARN_ON_ONCE(tx->rate.idx < 0))
+ return 0;
--- /dev/null
+From: Felix Fietkau <nbd@nbd.name>
+Date: Wed, 14 Dec 2016 20:13:58 +0100
+Subject: [PATCH] mac80211: minstrel: remove cur_prob from debugfs
+
+This field is redundant, because it is simply last success divided by
+last attempt count. Removing it from the rate stats struct saves about
+1.2 KiB per HT station.
+
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+---
+
+--- a/net/mac80211/rc80211_minstrel.c
++++ b/net/mac80211/rc80211_minstrel.c
+@@ -159,21 +159,23 @@ minstrel_update_rates(struct minstrel_pr
+ void
+ minstrel_calc_rate_stats(struct minstrel_rate_stats *mrs)
+ {
++ unsigned int cur_prob;
++
+ if (unlikely(mrs->attempts > 0)) {
+ mrs->sample_skipped = 0;
+- mrs->cur_prob = MINSTREL_FRAC(mrs->success, mrs->attempts);
++ cur_prob = MINSTREL_FRAC(mrs->success, mrs->attempts);
+ if (unlikely(!mrs->att_hist)) {
+- mrs->prob_ewma = mrs->cur_prob;
++ mrs->prob_ewma = cur_prob;
+ } else {
+ /* update exponential weighted moving variance */
+ mrs->prob_ewmsd = minstrel_ewmsd(mrs->prob_ewmsd,
+- mrs->cur_prob,
++ cur_prob,
+ mrs->prob_ewma,
+ EWMA_LEVEL);
+
+ /*update exponential weighted moving avarage */
+ mrs->prob_ewma = minstrel_ewma(mrs->prob_ewma,
+- mrs->cur_prob,
++ cur_prob,
+ EWMA_LEVEL);
+ }
+ mrs->att_hist += mrs->attempts;
+--- a/net/mac80211/rc80211_minstrel.h
++++ b/net/mac80211/rc80211_minstrel.h
+@@ -62,10 +62,8 @@ struct minstrel_rate_stats {
+ u32 att_hist, succ_hist;
+
+ /* statistis of packet delivery probability
+- * cur_prob - current prob within last update intervall
+ * prob_ewma - exponential weighted moving average of prob
+ * prob_ewmsd - exp. weighted moving standard deviation of prob */
+- unsigned int cur_prob;
+ unsigned int prob_ewma;
+ u16 prob_ewmsd;
+
+--- a/net/mac80211/rc80211_minstrel_debugfs.c
++++ b/net/mac80211/rc80211_minstrel_debugfs.c
+@@ -75,7 +75,7 @@ minstrel_stats_open(struct inode *inode,
+ {
+ struct minstrel_sta_info *mi = inode->i_private;
+ struct minstrel_debugfs_info *ms;
+- unsigned int i, tp_max, tp_avg, prob, eprob;
++ unsigned int i, tp_max, tp_avg, eprob;
+ char *p;
+
+ ms = kmalloc(2048, GFP_KERNEL);
+@@ -86,9 +86,9 @@ minstrel_stats_open(struct inode *inode,
+ p = ms->buf;
+ p += sprintf(p, "\n");
+ p += sprintf(p,
+- "best __________rate_________ ________statistics________ ________last_______ ______sum-of________\n");
++ "best __________rate_________ ________statistics________ ____last_____ ______sum-of________\n");
+ p += sprintf(p,
+- "rate [name idx airtime max_tp] [avg(tp) avg(prob) sd(prob)] [prob.|retry|suc|att] [#success | #attempts]\n");
++ "rate [name idx airtime max_tp] [avg(tp) avg(prob) sd(prob)] [retry|suc|att] [#success | #attempts]\n");
+
+ for (i = 0; i < mi->n_rates; i++) {
+ struct minstrel_rate *mr = &mi->r[i];
+@@ -107,17 +107,15 @@ minstrel_stats_open(struct inode *inode,
+
+ tp_max = minstrel_get_tp_avg(mr, MINSTREL_FRAC(100,100));
+ tp_avg = minstrel_get_tp_avg(mr, mrs->prob_ewma);
+- prob = MINSTREL_TRUNC(mrs->cur_prob * 1000);
+ eprob = MINSTREL_TRUNC(mrs->prob_ewma * 1000);
+
+ p += sprintf(p, "%4u.%1u %4u.%1u %3u.%1u %3u.%1u"
+- " %3u.%1u %3u %3u %-3u "
++ " %3u %3u %-3u "
+ "%9llu %-9llu\n",
+ tp_max / 10, tp_max % 10,
+ tp_avg / 10, tp_avg % 10,
+ eprob / 10, eprob % 10,
+ mrs->prob_ewmsd / 10, mrs->prob_ewmsd % 10,
+- prob / 10, prob % 10,
+ mrs->retry_count,
+ mrs->last_success,
+ mrs->last_attempts,
+@@ -148,7 +146,7 @@ minstrel_stats_csv_open(struct inode *in
+ {
+ struct minstrel_sta_info *mi = inode->i_private;
+ struct minstrel_debugfs_info *ms;
+- unsigned int i, tp_max, tp_avg, prob, eprob;
++ unsigned int i, tp_max, tp_avg, eprob;
+ char *p;
+
+ ms = kmalloc(2048, GFP_KERNEL);
+@@ -175,16 +173,14 @@ minstrel_stats_csv_open(struct inode *in
+
+ tp_max = minstrel_get_tp_avg(mr, MINSTREL_FRAC(100,100));
+ tp_avg = minstrel_get_tp_avg(mr, mrs->prob_ewma);
+- prob = MINSTREL_TRUNC(mrs->cur_prob * 1000);
+ eprob = MINSTREL_TRUNC(mrs->prob_ewma * 1000);
+
+- p += sprintf(p, "%u.%u,%u.%u,%u.%u,%u.%u,%u.%u,%u,%u,%u,"
++ p += sprintf(p, "%u.%u,%u.%u,%u.%u,%u.%u,%u,%u,%u,"
+ "%llu,%llu,%d,%d\n",
+ tp_max / 10, tp_max % 10,
+ tp_avg / 10, tp_avg % 10,
+ eprob / 10, eprob % 10,
+ mrs->prob_ewmsd / 10, mrs->prob_ewmsd % 10,
+- prob / 10, prob % 10,
+ mrs->retry_count,
+ mrs->last_success,
+ mrs->last_attempts,
+--- a/net/mac80211/rc80211_minstrel_ht_debugfs.c
++++ b/net/mac80211/rc80211_minstrel_ht_debugfs.c
+@@ -19,7 +19,7 @@ static char *
+ minstrel_ht_stats_dump(struct minstrel_ht_sta *mi, int i, char *p)
+ {
+ const struct mcs_group *mg;
+- unsigned int j, tp_max, tp_avg, prob, eprob, tx_time;
++ unsigned int j, tp_max, tp_avg, eprob, tx_time;
+ char htmode = '2';
+ char gimode = 'L';
+ u32 gflags;
+@@ -83,17 +83,15 @@ minstrel_ht_stats_dump(struct minstrel_h
+
+ 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);
+- prob = MINSTREL_TRUNC(mrs->cur_prob * 1000);
+ eprob = MINSTREL_TRUNC(mrs->prob_ewma * 1000);
+
+ p += sprintf(p, "%4u.%1u %4u.%1u %3u.%1u %3u.%1u"
+- " %3u.%1u %3u %3u %-3u "
++ " %3u %3u %-3u "
+ "%9llu %-9llu\n",
+ tp_max / 10, tp_max % 10,
+ tp_avg / 10, tp_avg % 10,
+ eprob / 10, eprob % 10,
+ mrs->prob_ewmsd / 10, mrs->prob_ewmsd % 10,
+- prob / 10, prob % 10,
+ mrs->retry_count,
+ mrs->last_success,
+ mrs->last_attempts,
+@@ -130,9 +128,9 @@ minstrel_ht_stats_open(struct inode *ino
+
+ p += sprintf(p, "\n");
+ p += sprintf(p,
+- " best ____________rate__________ ________statistics________ ________last_______ ______sum-of________\n");
++ " best ____________rate__________ ________statistics________ _____last____ ______sum-of________\n");
+ p += sprintf(p,
+- "mode guard # rate [name idx airtime max_tp] [avg(tp) avg(prob) sd(prob)] [prob.|retry|suc|att] [#success | #attempts]\n");
++ "mode guard # rate [name idx airtime max_tp] [avg(tp) avg(prob) sd(prob)] [retry|suc|att] [#success | #attempts]\n");
+
+ p = minstrel_ht_stats_dump(mi, MINSTREL_CCK_GROUP, p);
+ for (i = 0; i < MINSTREL_CCK_GROUP; i++)
+@@ -165,7 +163,7 @@ static char *
+ minstrel_ht_stats_csv_dump(struct minstrel_ht_sta *mi, int i, char *p)
+ {
+ const struct mcs_group *mg;
+- unsigned int j, tp_max, tp_avg, prob, eprob, tx_time;
++ unsigned int j, tp_max, tp_avg, eprob, tx_time;
+ char htmode = '2';
+ char gimode = 'L';
+ u32 gflags;
+@@ -226,16 +224,14 @@ minstrel_ht_stats_csv_dump(struct minstr
+
+ 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);
+- prob = MINSTREL_TRUNC(mrs->cur_prob * 1000);
+ eprob = MINSTREL_TRUNC(mrs->prob_ewma * 1000);
+
+- p += sprintf(p, "%u.%u,%u.%u,%u.%u,%u.%u,%u.%u,%u,%u,"
++ p += sprintf(p, "%u.%u,%u.%u,%u.%u,%u.%u,%u,%u,"
+ "%u,%llu,%llu,",
+ tp_max / 10, tp_max % 10,
+ tp_avg / 10, tp_avg % 10,
+ eprob / 10, eprob % 10,
+ mrs->prob_ewmsd / 10, mrs->prob_ewmsd % 10,
+- prob / 10, prob % 10,
+ mrs->retry_count,
+ mrs->last_success,
+ mrs->last_attempts,
--- /dev/null
+From: Felix Fietkau <nbd@nbd.name>
+Date: Wed, 14 Dec 2016 20:15:33 +0100
+Subject: [PATCH] mac80211: minstrel: reduce MINSTREL_SCALE
+
+The loss of a bit of extra precision does not hurt the calculation, 12
+bits is still enough to calculate probabilities well. Reducing the scale
+makes it easier to avoid overflows
+
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+---
+
+--- a/net/mac80211/rc80211_minstrel.h
++++ b/net/mac80211/rc80211_minstrel.h
+@@ -14,7 +14,7 @@
+ #define SAMPLE_COLUMNS 10 /* number of columns in sample table */
+
+ /* scaled fraction values */
+-#define MINSTREL_SCALE 16
++#define MINSTREL_SCALE 12
+ #define MINSTREL_FRAC(val, div) (((val) << MINSTREL_SCALE) / div)
+ #define MINSTREL_TRUNC(val) ((val) >> MINSTREL_SCALE)
+
--- /dev/null
+From: Felix Fietkau <nbd@nbd.name>
+Date: Wed, 14 Dec 2016 20:17:06 +0100
+Subject: [PATCH] mac80211: minstrel: store probability variance instead of
+ standard deviation
+
+This avoids the costly int_sqrt calls in the statistics update and moves
+it to the debugfs code instead.
+This also fixes an overflow in the previous standard deviation
+calculation.
+
+Signed-off-by: Thomas Huehn <thomas.huehn@evernet-eg.de>
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+---
+
+--- a/net/mac80211/rc80211_minstrel.c
++++ b/net/mac80211/rc80211_minstrel.c
+@@ -168,10 +168,10 @@ minstrel_calc_rate_stats(struct minstrel
+ mrs->prob_ewma = cur_prob;
+ } else {
+ /* update exponential weighted moving variance */
+- mrs->prob_ewmsd = minstrel_ewmsd(mrs->prob_ewmsd,
+- cur_prob,
+- mrs->prob_ewma,
+- EWMA_LEVEL);
++ mrs->prob_ewmv = minstrel_ewmv(mrs->prob_ewmv,
++ cur_prob,
++ mrs->prob_ewma,
++ EWMA_LEVEL);
+
+ /*update exponential weighted moving avarage */
+ mrs->prob_ewma = minstrel_ewma(mrs->prob_ewma,
+--- a/net/mac80211/rc80211_minstrel.h
++++ b/net/mac80211/rc80211_minstrel.h
+@@ -36,21 +36,16 @@ minstrel_ewma(int old, int new, int weig
+ }
+
+ /*
+- * Perform EWMSD (Exponentially Weighted Moving Standard Deviation) calculation
++ * Perform EWMV (Exponentially Weighted Moving Variance) calculation
+ */
+ static inline int
+-minstrel_ewmsd(int old_ewmsd, int cur_prob, int prob_ewma, int weight)
++minstrel_ewmv(int old_ewmv, int cur_prob, int prob_ewma, int weight)
+ {
+- int diff, incr, tmp_var;
++ int diff, incr;
+
+- /* calculate exponential weighted moving variance */
+- diff = MINSTREL_TRUNC((cur_prob - prob_ewma) * 1000000);
++ diff = cur_prob - prob_ewma;
+ incr = (EWMA_DIV - weight) * diff / EWMA_DIV;
+- tmp_var = old_ewmsd * old_ewmsd;
+- tmp_var = weight * (tmp_var + diff * incr / 1000000) / EWMA_DIV;
+-
+- /* return standard deviation */
+- return (u16) int_sqrt(tmp_var);
++ return weight * (old_ewmv + MINSTREL_TRUNC(diff * incr)) / EWMA_DIV;
+ }
+
+ struct minstrel_rate_stats {
+@@ -65,7 +60,7 @@ struct minstrel_rate_stats {
+ * prob_ewma - exponential weighted moving average of prob
+ * prob_ewmsd - exp. weighted moving standard deviation of prob */
+ unsigned int prob_ewma;
+- u16 prob_ewmsd;
++ u16 prob_ewmv;
+
+ /* maximum retry counts */
+ u8 retry_count;
+@@ -151,6 +146,14 @@ struct minstrel_debugfs_info {
+ char buf[];
+ };
+
++/* Get EWMSD (Exponentially Weighted Moving Standard Deviation) * 10 */
++static inline int
++minstrel_get_ewmsd10(struct minstrel_rate_stats *mrs)
++{
++ unsigned int ewmv = mrs->prob_ewmv;
++ return int_sqrt(MINSTREL_TRUNC(ewmv * 1000 * 1000));
++}
++
+ extern const struct rate_control_ops mac80211_minstrel;
+ void minstrel_add_sta_debugfs(void *priv, void *priv_sta, struct dentry *dir);
+ void minstrel_remove_sta_debugfs(void *priv, void *priv_sta);
+--- a/net/mac80211/rc80211_minstrel_debugfs.c
++++ b/net/mac80211/rc80211_minstrel_debugfs.c
+@@ -93,6 +93,7 @@ minstrel_stats_open(struct inode *inode,
+ for (i = 0; i < mi->n_rates; i++) {
+ struct minstrel_rate *mr = &mi->r[i];
+ struct minstrel_rate_stats *mrs = &mi->r[i].stats;
++ unsigned int prob_ewmsd;
+
+ *(p++) = (i == mi->max_tp_rate[0]) ? 'A' : ' ';
+ *(p++) = (i == mi->max_tp_rate[1]) ? 'B' : ' ';
+@@ -108,6 +109,7 @@ minstrel_stats_open(struct inode *inode,
+ 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);
++ prob_ewmsd = minstrel_get_ewmsd10(mrs);
+
+ p += sprintf(p, "%4u.%1u %4u.%1u %3u.%1u %3u.%1u"
+ " %3u %3u %-3u "
+@@ -115,7 +117,7 @@ minstrel_stats_open(struct inode *inode,
+ tp_max / 10, tp_max % 10,
+ tp_avg / 10, tp_avg % 10,
+ eprob / 10, eprob % 10,
+- mrs->prob_ewmsd / 10, mrs->prob_ewmsd % 10,
++ prob_ewmsd / 10, prob_ewmsd % 10,
+ mrs->retry_count,
+ mrs->last_success,
+ mrs->last_attempts,
+@@ -159,6 +161,7 @@ minstrel_stats_csv_open(struct inode *in
+ for (i = 0; i < mi->n_rates; i++) {
+ struct minstrel_rate *mr = &mi->r[i];
+ struct minstrel_rate_stats *mrs = &mi->r[i].stats;
++ unsigned int prob_ewmsd;
+
+ p += sprintf(p, "%s" ,((i == mi->max_tp_rate[0]) ? "A" : ""));
+ p += sprintf(p, "%s" ,((i == mi->max_tp_rate[1]) ? "B" : ""));
+@@ -174,13 +177,14 @@ minstrel_stats_csv_open(struct inode *in
+ 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);
++ prob_ewmsd = minstrel_get_ewmsd10(mrs);
+
+ p += sprintf(p, "%u.%u,%u.%u,%u.%u,%u.%u,%u,%u,%u,"
+ "%llu,%llu,%d,%d\n",
+ tp_max / 10, tp_max % 10,
+ tp_avg / 10, tp_avg % 10,
+ eprob / 10, eprob % 10,
+- mrs->prob_ewmsd / 10, mrs->prob_ewmsd % 10,
++ prob_ewmsd / 10, prob_ewmsd % 10,
+ mrs->retry_count,
+ mrs->last_success,
+ mrs->last_attempts,
+--- a/net/mac80211/rc80211_minstrel_ht_debugfs.c
++++ b/net/mac80211/rc80211_minstrel_ht_debugfs.c
+@@ -41,6 +41,7 @@ minstrel_ht_stats_dump(struct minstrel_h
+ struct minstrel_rate_stats *mrs = &mi->groups[i].rates[j];
+ static const int bitrates[4] = { 10, 20, 55, 110 };
+ int idx = i * MCS_GROUP_RATES + j;
++ unsigned int prob_ewmsd;
+
+ if (!(mi->supported[i] & BIT(j)))
+ continue;
+@@ -84,6 +85,7 @@ minstrel_ht_stats_dump(struct minstrel_h
+ 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);
++ prob_ewmsd = minstrel_get_ewmsd10(mrs);
+
+ p += sprintf(p, "%4u.%1u %4u.%1u %3u.%1u %3u.%1u"
+ " %3u %3u %-3u "
+@@ -91,7 +93,7 @@ minstrel_ht_stats_dump(struct minstrel_h
+ tp_max / 10, tp_max % 10,
+ tp_avg / 10, tp_avg % 10,
+ eprob / 10, eprob % 10,
+- mrs->prob_ewmsd / 10, mrs->prob_ewmsd % 10,
++ prob_ewmsd / 10, prob_ewmsd % 10,
+ mrs->retry_count,
+ mrs->last_success,
+ mrs->last_attempts,
+@@ -185,6 +187,7 @@ minstrel_ht_stats_csv_dump(struct minstr
+ struct minstrel_rate_stats *mrs = &mi->groups[i].rates[j];
+ static const int bitrates[4] = { 10, 20, 55, 110 };
+ int idx = i * MCS_GROUP_RATES + j;
++ unsigned int prob_ewmsd;
+
+ if (!(mi->supported[i] & BIT(j)))
+ continue;
+@@ -225,13 +228,14 @@ minstrel_ht_stats_csv_dump(struct minstr
+ 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);
++ prob_ewmsd = minstrel_get_ewmsd10(mrs);
+
+ p += sprintf(p, "%u.%u,%u.%u,%u.%u,%u.%u,%u,%u,"
+ "%u,%llu,%llu,",
+ tp_max / 10, tp_max % 10,
+ tp_avg / 10, tp_avg % 10,
+ eprob / 10, eprob % 10,
+- mrs->prob_ewmsd / 10, mrs->prob_ewmsd % 10,
++ prob_ewmsd / 10, prob_ewmsd % 10,
+ mrs->retry_count,
+ mrs->last_success,
+ mrs->last_attempts,
--- /dev/null
+From: Felix Fietkau <nbd@nbd.name>
+Date: Wed, 14 Dec 2016 20:19:56 +0100
+Subject: [PATCH] mac80211: minstrel: make prob_ewma u16 instead of u32
+
+Saves about 1.2 KiB memory per station
+
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+---
+
+--- a/net/mac80211/rc80211_minstrel.h
++++ b/net/mac80211/rc80211_minstrel.h
+@@ -59,7 +59,7 @@ struct minstrel_rate_stats {
+ /* statistis of packet delivery probability
+ * prob_ewma - exponential weighted moving average of prob
+ * prob_ewmsd - exp. weighted moving standard deviation of prob */
+- unsigned int prob_ewma;
++ u16 prob_ewma;
+ u16 prob_ewmv;
+
+ /* maximum retry counts */
--- /dev/null
+From: Felix Fietkau <nbd@nbd.name>
+Date: Wed, 14 Dec 2016 20:23:29 +0100
+Subject: [PATCH] mac80211: minstrel_ht: remove obsolete #if for >= 3 streams
+
+This was added during early development when 3x3 hardware was not very
+common yet. This is completely unnecessary now.
+
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+---
+
+--- a/net/mac80211/rc80211_minstrel_ht.c
++++ b/net/mac80211/rc80211_minstrel_ht.c
+@@ -155,67 +155,47 @@ MODULE_PARM_DESC(minstrel_vht_only,
+ const struct mcs_group minstrel_mcs_groups[] = {
+ MCS_GROUP(1, 0, BW_20),
+ MCS_GROUP(2, 0, BW_20),
+-#if MINSTREL_MAX_STREAMS >= 3
+ MCS_GROUP(3, 0, BW_20),
+-#endif
+
+ MCS_GROUP(1, 1, BW_20),
+ MCS_GROUP(2, 1, BW_20),
+-#if MINSTREL_MAX_STREAMS >= 3
+ MCS_GROUP(3, 1, BW_20),
+-#endif
+
+ MCS_GROUP(1, 0, BW_40),
+ MCS_GROUP(2, 0, BW_40),
+-#if MINSTREL_MAX_STREAMS >= 3
+ MCS_GROUP(3, 0, BW_40),
+-#endif
+
+ MCS_GROUP(1, 1, BW_40),
+ MCS_GROUP(2, 1, BW_40),
+-#if MINSTREL_MAX_STREAMS >= 3
+ MCS_GROUP(3, 1, BW_40),
+-#endif
+
+ CCK_GROUP,
+
+ #ifdef CPTCFG_MAC80211_RC_MINSTREL_VHT
+ VHT_GROUP(1, 0, BW_20),
+ VHT_GROUP(2, 0, BW_20),
+-#if MINSTREL_MAX_STREAMS >= 3
+ VHT_GROUP(3, 0, BW_20),
+-#endif
+
+ VHT_GROUP(1, 1, BW_20),
+ VHT_GROUP(2, 1, BW_20),
+-#if MINSTREL_MAX_STREAMS >= 3
+ VHT_GROUP(3, 1, BW_20),
+-#endif
+
+ VHT_GROUP(1, 0, BW_40),
+ VHT_GROUP(2, 0, BW_40),
+-#if MINSTREL_MAX_STREAMS >= 3
+ VHT_GROUP(3, 0, BW_40),
+-#endif
+
+ VHT_GROUP(1, 1, BW_40),
+ VHT_GROUP(2, 1, BW_40),
+-#if MINSTREL_MAX_STREAMS >= 3
+ VHT_GROUP(3, 1, BW_40),
+-#endif
+
+ VHT_GROUP(1, 0, BW_80),
+ VHT_GROUP(2, 0, BW_80),
+-#if MINSTREL_MAX_STREAMS >= 3
+ VHT_GROUP(3, 0, BW_80),
+-#endif
+
+ VHT_GROUP(1, 1, BW_80),
+ VHT_GROUP(2, 1, BW_80),
+-#if MINSTREL_MAX_STREAMS >= 3
+ VHT_GROUP(3, 1, BW_80),
+ #endif
+-#endif
+ };
+
+ static u8 sample_table[SAMPLE_COLUMNS][MCS_GROUP_RATES] __read_mostly;
projects / openwrt / openwrt.git / commitdiff