diff options
Diffstat (limited to 'package/kernel/mac80211/patches/343-mac80211-minstrel_ht-improve-sample-rate-skip-logic.patch')
| -rw-r--r-- | package/kernel/mac80211/patches/343-mac80211-minstrel_ht-improve-sample-rate-skip-logic.patch | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/package/kernel/mac80211/patches/343-mac80211-minstrel_ht-improve-sample-rate-skip-logic.patch b/package/kernel/mac80211/patches/343-mac80211-minstrel_ht-improve-sample-rate-skip-logic.patch new file mode 100644 index 0000000..55ff817 --- /dev/null +++ b/package/kernel/mac80211/patches/343-mac80211-minstrel_ht-improve-sample-rate-skip-logic.patch @@ -0,0 +1,77 @@ +From: Felix Fietkau <nbd@openwrt.org> +Date: Thu, 3 Mar 2016 23:20:06 +0100 +Subject: [PATCH] mac80211: minstrel_ht: improve sample rate skip logic + +There were a few issues that were slowing down the process of finding +the optimal rate, especially on devices with multi-rate retry +limitations: + +When max_tp_rate[0] was slower than max_tp_rate[1], the code did not +sample max_tp_rate[1], which would often allow it to switch places with +max_tp_rate[0] (e.g. if only the first sampling attempts were bad, but the +rate is otherwise good). + +Also, sample attempts of rates between max_tp_rate[0] and [1] were being +ignored in this case, because the code only checked if the rate was +slower than [1]. + +Fix this by checking against the fastest / second fastest max_tp_rate +instead of assuming a specific order between the two. + +In my tests this patch significantly reduces the time until minstrel_ht +finds the optimal rate right after assoc + +Signed-off-by: Felix Fietkau <nbd@openwrt.org> +--- + +--- a/net/mac80211/rc80211_minstrel_ht.c ++++ b/net/mac80211/rc80211_minstrel_ht.c +@@ -958,6 +958,7 @@ minstrel_get_sample_rate(struct minstrel + 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 (mi->sample_wait > 0) { +@@ -979,14 +980,22 @@ minstrel_get_sample_rate(struct minstrel + mrs = &mg->rates[sample_idx]; + sample_idx += sample_group * MCS_GROUP_RATES; + ++ /* Set tp_rate1, tp_rate2 to the highest / second highest max_tp_rate */ ++ if (minstrel_get_duration(mi->max_tp_rate[0]) > ++ minstrel_get_duration(mi->max_tp_rate[1])) { ++ tp_rate1 = mi->max_tp_rate[1]; ++ tp_rate2 = mi->max_tp_rate[0]; ++ } else { ++ tp_rate1 = mi->max_tp_rate[0]; ++ tp_rate2 = mi->max_tp_rate[1]; ++ } ++ + /* + * Sampling might add some overhead (RTS, no aggregation) +- * to the frame. Hence, don't use sampling for the currently +- * used rates. ++ * to the frame. Hence, don't use sampling for the highest currently ++ * used highest throughput or probability rate. + */ +- if (sample_idx == mi->max_tp_rate[0] || +- sample_idx == mi->max_tp_rate[1] || +- sample_idx == mi->max_prob_rate) ++ if (sample_idx == mi->max_tp_rate[0] || sample_idx == mi->max_prob_rate) + return -1; + + /* +@@ -1001,10 +1010,10 @@ minstrel_get_sample_rate(struct minstrel + * if the link is working perfectly. + */ + +- cur_max_tp_streams = minstrel_mcs_groups[mi->max_tp_rate[0] / ++ cur_max_tp_streams = minstrel_mcs_groups[tp_rate1 / + MCS_GROUP_RATES].streams; + sample_dur = minstrel_get_duration(sample_idx); +- if (sample_dur >= minstrel_get_duration(mi->max_tp_rate[1]) && ++ 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))) { |