ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/package/kernel/mac80211/patches/subsys/348-mac80211-minstrel_ht-reduce-the-need-to-sample-slowe.patch b/package/kernel/mac80211/patches/subsys/348-mac80211-minstrel_ht-reduce-the-need-to-sample-slowe.patch
new file mode 100644
index 0000000..dc6f11e
--- /dev/null
+++ b/package/kernel/mac80211/patches/subsys/348-mac80211-minstrel_ht-reduce-the-need-to-sample-slowe.patch
@@ -0,0 +1,102 @@
+From: Felix Fietkau <nbd@nbd.name>
+Date: Fri, 22 Jan 2021 19:24:59 +0100
+Subject: [PATCH] mac80211: minstrel_ht: reduce the need to sample slower
+ rates
+
+In order to more gracefully be able to fall back to lower rates without too
+much throughput fluctuations, initialize all untested rates below tested ones
+to the maximum probabilty of higher rates.
+Usually this leads to untested lower rates getting initialized with a
+probability value of 100%, making them better candidates for fallback without
+having to rely on random probing
+
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+---
+
+--- a/net/mac80211/rc80211_minstrel_ht.c
++++ b/net/mac80211/rc80211_minstrel_ht.c
+@@ -791,14 +791,11 @@ minstrel_ht_calc_rate_stats(struct minst
+ 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;
+@@ -851,7 +848,6 @@ minstrel_ht_update_stats(struct minstrel
+ mi->ampdu_packets = 0;
+ }
+
+- mi->sample_slow = 0;
+ mi->sample_count = 0;
+
+ if (mi->supported[MINSTREL_CCK_GROUP])
+@@ -882,6 +878,7 @@ minstrel_ht_update_stats(struct minstrel
+ /* 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])
+@@ -896,7 +893,7 @@ minstrel_ht_update_stats(struct minstrel
+ 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;
+
+@@ -905,6 +902,11 @@ minstrel_ht_update_stats(struct minstrel
+ 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)
+@@ -1469,13 +1471,9 @@ minstrel_get_sample_rate(struct minstrel
+ if (sample_dur >= minstrel_get_duration(tp_rate2) &&
+ (cur_max_tp_streams - 1 <
+ minstrel_mcs_groups[sample_group].streams ||
+- sample_dur >= minstrel_get_duration(mi->max_prob_rate))) {
+- if (mrs->sample_skipped < 20)
++ sample_dur >= minstrel_get_duration(mi->max_prob_rate)))
+ return -1;
+
+- if (mi->sample_slow++ > 2)
+- return -1;
+- }
+ mi->sample_tries--;
+
+ return sample_idx;
+--- a/net/mac80211/rc80211_minstrel_ht.h
++++ b/net/mac80211/rc80211_minstrel_ht.h
+@@ -123,7 +123,6 @@ struct minstrel_rate_stats {
+ u8 retry_count;
+ u8 retry_count_rtscts;
+
+- u8 sample_skipped;
+ bool retry_updated;
+ };
+
+@@ -179,7 +178,6 @@ struct minstrel_ht_sta {
+ u8 sample_wait;
+ u8 sample_tries;
+ u8 sample_count;
+- u8 sample_slow;
+
+ enum minstrel_sample_mode sample_mode;
+ u16 sample_rate;