[PATCH v3 5/9] mac80211: minstrel_ht: improve ampdu length estimation

Felix Fietkau
2021-01-15T12:04:00Z

If the driver does not report A-MPDU length, estimate it based on the rate.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
net/mac80211/rc80211_minstrel_ht.c | 38 +++++++++++++++++++++---------
1 file changed, 27 insertions(+), 11 deletions(-)

diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c
index 9280461ed3cc..5b20e17ec2e6 100644
--- a/net/mac80211/rc80211_minstrel_ht.c
+++ b/net/mac80211/rc80211_minstrel_ht.c
@@ -382,13 +382,37 @@ minstrel_get_ratestats(struct minstrel_ht_sta *mi, int index)
return &mi->groups[index / MCS_GROUP_RATES].rates[index % MCS_GROUP_RATES];
}

+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];
+ return duration << group->shift;
+}
+
static unsigned int
minstrel_ht_avg_ampdu_len(struct minstrel_ht_sta *mi)
{
- if (!mi->avg_ampdu_len)
- return AVG_AMPDU_SIZE;
+ int duration;
+
+ 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))
+ return 1;
+
+ duration = minstrel_get_duration(mi->max_tp_rate[0]);

- return MINSTREL_TRUNC(mi->avg_ampdu_len);
+ if (duration > 400 * 1000)
+ return 2;
+
+ if (duration > 250 * 1000)
+ return 4;
+
+ if (duration > 150 * 1000)
+ return 8;
+
+ return 16;
}

/*
@@ -588,14 +612,6 @@ minstrel_ht_prob_rate_reduce_streams(struct minstrel_ht_sta *mi)
}
}

-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];
- return duration << group->shift;
-}
-
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)
--
2.28.0