From 28b6a09fbf23d2616af88b13b5654e89bda74777 Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Sat, 6 Oct 2018 19:35:05 +0200 Subject: [PATCH] mac80211: minstrel: fix sampling/reporting of CCK rates in HT mode [ Upstream commit 972b66b86f85f4e8201db454f4c3e9d990cf9836 ] Long/short preamble selection cannot be sampled separately, since it depends on the BSS state. Because of that, sampling attempts to currently not used preamble modes are not counted in the statistics, which leads to CCK rates being sampled too often. Fix statistics accounting for long/short preamble by increasing the index where necessary. Fix excessive CCK rate sampling by dropping unsupported sample attempts. This improves throughput on 2.4 GHz channels Signed-off-by: Felix Fietkau Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin --- net/mac80211/rc80211_minstrel_ht.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c index bc97d31907f6..e57811e4b91f 100644 --- a/net/mac80211/rc80211_minstrel_ht.c +++ b/net/mac80211/rc80211_minstrel_ht.c @@ -282,7 +282,8 @@ minstrel_ht_get_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, break; /* short preamble */ - if (!(mi->supported[group] & BIT(idx))) + if ((mi->supported[group] & BIT(idx + 4)) && + (rate->flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)) idx += 4; } return &mi->groups[group].rates[idx]; @@ -1077,18 +1078,23 @@ minstrel_ht_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta, return; sample_group = &minstrel_mcs_groups[sample_idx / MCS_GROUP_RATES]; + sample_idx %= MCS_GROUP_RATES; + + if (sample_group == &minstrel_mcs_groups[MINSTREL_CCK_GROUP] && + (sample_idx >= 4) != txrc->short_preamble) + return; + info->flags |= IEEE80211_TX_CTL_RATE_CTRL_PROBE; rate->count = 1; - if (sample_idx / MCS_GROUP_RATES == MINSTREL_CCK_GROUP) { + if (sample_group == &minstrel_mcs_groups[MINSTREL_CCK_GROUP]) { int idx = sample_idx % ARRAY_SIZE(mp->cck_rates); rate->idx = mp->cck_rates[idx]; } else if (sample_group->flags & IEEE80211_TX_RC_VHT_MCS) { ieee80211_rate_set_vht(rate, sample_idx % MCS_GROUP_RATES, sample_group->streams); } else { - rate->idx = sample_idx % MCS_GROUP_RATES + - (sample_group->streams - 1) * 8; + rate->idx = sample_idx + (sample_group->streams - 1) * 8; } rate->flags = sample_group->flags; -- 2.20.1