* [PATCH 1/6] mac80211: minstrel_ht: use bitfields to encode rate indexes
@ 2021-01-24 12:28 Felix Fietkau
2021-01-24 12:28 ` [PATCH 2/6] mac80211: minstrel_ht: update total packets counter in tx status path Felix Fietkau
` (5 more replies)
0 siblings, 6 replies; 12+ messages in thread
From: Felix Fietkau @ 2021-01-24 12:28 UTC (permalink / raw)
To: linux-wireless; +Cc: johannes
Get rid of a lot of divisions and modulo operations
Reduces code size and improves performance
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
net/mac80211/rc80211_minstrel_ht.c | 123 +++++++++++----------
net/mac80211/rc80211_minstrel_ht.h | 13 +++
net/mac80211/rc80211_minstrel_ht_debugfs.c | 4 +-
3 files changed, 78 insertions(+), 62 deletions(-)
diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c
index e35948f4e1bf..a3b86fd300f0 100644
--- a/net/mac80211/rc80211_minstrel_ht.c
+++ b/net/mac80211/rc80211_minstrel_ht.c
@@ -379,13 +379,13 @@ minstrel_ht_get_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
static inline struct minstrel_rate_stats *
minstrel_get_ratestats(struct minstrel_ht_sta *mi, int index)
{
- return &mi->groups[index / MCS_GROUP_RATES].rates[index % MCS_GROUP_RATES];
+ return &mi->groups[MI_RATE_GROUP(index)].rates[MI_RATE_IDX(index)];
}
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];
+ const struct mcs_group *group = &minstrel_mcs_groups[MI_RATE_GROUP(index)];
+ unsigned int duration = group->duration[MI_RATE_IDX(index)];
return duration << group->shift;
}
@@ -398,7 +398,7 @@ minstrel_ht_avg_ampdu_len(struct minstrel_ht_sta *mi)
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))
+ if (minstrel_ht_is_legacy_group(MI_RATE_GROUP(mi->max_tp_rate[0])))
return 1;
duration = minstrel_get_duration(mi->max_tp_rate[0]);
@@ -465,14 +465,14 @@ minstrel_ht_sort_best_tp_rates(struct minstrel_ht_sta *mi, u16 index,
int tmp_group, tmp_idx, tmp_tp_avg, tmp_prob;
int j = MAX_THR_RATES;
- cur_group = index / MCS_GROUP_RATES;
- cur_idx = index % MCS_GROUP_RATES;
+ cur_group = MI_RATE_GROUP(index);
+ cur_idx = MI_RATE_IDX(index);
cur_prob = mi->groups[cur_group].rates[cur_idx].prob_avg;
cur_tp_avg = minstrel_ht_get_tp_avg(mi, cur_group, cur_idx, cur_prob);
do {
- tmp_group = tp_list[j - 1] / MCS_GROUP_RATES;
- tmp_idx = tp_list[j - 1] % MCS_GROUP_RATES;
+ tmp_group = MI_RATE_GROUP(tp_list[j - 1]);
+ tmp_idx = MI_RATE_IDX(tp_list[j - 1]);
tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_avg;
tmp_tp_avg = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx,
tmp_prob);
@@ -504,23 +504,23 @@ minstrel_ht_set_best_prob_rate(struct minstrel_ht_sta *mi, u16 *dest, u16 index)
int max_gpr_group, max_gpr_idx;
int max_gpr_tp_avg, max_gpr_prob;
- cur_group = index / MCS_GROUP_RATES;
- cur_idx = index % MCS_GROUP_RATES;
- mg = &mi->groups[index / MCS_GROUP_RATES];
- mrs = &mg->rates[index % MCS_GROUP_RATES];
+ cur_group = MI_RATE_GROUP(index);
+ cur_idx = MI_RATE_IDX(index);
+ mg = &mi->groups[cur_group];
+ mrs = &mg->rates[cur_idx];
- tmp_group = *dest / MCS_GROUP_RATES;
- tmp_idx = *dest % MCS_GROUP_RATES;
+ tmp_group = MI_RATE_GROUP(*dest);
+ tmp_idx = MI_RATE_IDX(*dest);
tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_avg;
tmp_tp_avg = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, tmp_prob);
/* if max_tp_rate[0] is from MCS_GROUP max_prob_rate get selected from
* MCS_GROUP as well as CCK_GROUP rates do not allow aggregation */
- max_tp_group = mi->max_tp_rate[0] / MCS_GROUP_RATES;
- max_tp_idx = mi->max_tp_rate[0] % MCS_GROUP_RATES;
+ max_tp_group = MI_RATE_GROUP(mi->max_tp_rate[0]);
+ max_tp_idx = MI_RATE_IDX(mi->max_tp_rate[0]);
max_tp_prob = mi->groups[max_tp_group].rates[max_tp_idx].prob_avg;
- if (minstrel_ht_is_legacy_group(index / MCS_GROUP_RATES) &&
+ if (minstrel_ht_is_legacy_group(MI_RATE_GROUP(index)) &&
!minstrel_ht_is_legacy_group(max_tp_group))
return;
@@ -529,8 +529,8 @@ minstrel_ht_set_best_prob_rate(struct minstrel_ht_sta *mi, u16 *dest, u16 index)
mrs->prob_avg < max_tp_prob)
return;
- max_gpr_group = mg->max_group_prob_rate / MCS_GROUP_RATES;
- max_gpr_idx = mg->max_group_prob_rate % MCS_GROUP_RATES;
+ max_gpr_group = MI_RATE_GROUP(mg->max_group_prob_rate);
+ max_gpr_idx = MI_RATE_IDX(mg->max_group_prob_rate);
max_gpr_prob = mi->groups[max_gpr_group].rates[max_gpr_idx].prob_avg;
if (mrs->prob_avg > MINSTREL_FRAC(75, 100)) {
@@ -567,13 +567,13 @@ minstrel_ht_assign_best_tp_rates(struct minstrel_ht_sta *mi,
unsigned int tmp_group, tmp_idx, tmp_cck_tp, tmp_mcs_tp, tmp_prob;
int i;
- tmp_group = tmp_legacy_tp_rate[0] / MCS_GROUP_RATES;
- tmp_idx = tmp_legacy_tp_rate[0] % MCS_GROUP_RATES;
+ tmp_group = MI_RATE_GROUP(tmp_legacy_tp_rate[0]);
+ tmp_idx = MI_RATE_IDX(tmp_legacy_tp_rate[0]);
tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_avg;
tmp_cck_tp = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, tmp_prob);
- tmp_group = tmp_mcs_tp_rate[0] / MCS_GROUP_RATES;
- tmp_idx = tmp_mcs_tp_rate[0] % MCS_GROUP_RATES;
+ tmp_group = MI_RATE_GROUP(tmp_mcs_tp_rate[0]);
+ tmp_idx = MI_RATE_IDX(tmp_mcs_tp_rate[0]);
tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_avg;
tmp_mcs_tp = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, tmp_prob);
@@ -600,14 +600,14 @@ minstrel_ht_prob_rate_reduce_streams(struct minstrel_ht_sta *mi)
if (!mi->sta->ht_cap.ht_supported)
return;
- tmp_max_streams = minstrel_mcs_groups[mi->max_tp_rate[0] /
- MCS_GROUP_RATES].streams;
+ group = MI_RATE_GROUP(mi->max_tp_rate[0]);
+ tmp_max_streams = minstrel_mcs_groups[group].streams;
for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) {
mg = &mi->groups[group];
if (!mi->supported[group] || group == MINSTREL_CCK_GROUP)
continue;
- tmp_idx = mg->max_group_prob_rate % MCS_GROUP_RATES;
+ tmp_idx = MI_RATE_IDX(mg->max_group_prob_rate);
tmp_prob = mi->groups[group].rates[tmp_idx].prob_avg;
if (tmp_tp < minstrel_ht_get_tp_avg(mi, group, tmp_idx, tmp_prob) &&
@@ -644,8 +644,8 @@ minstrel_ht_find_probe_rates(struct minstrel_ht_sta *mi, u16 *rates, int *n_rate
int i, g, max_dur;
int tp_idx;
- tp_group = &minstrel_mcs_groups[mi->max_tp_rate[0] / MCS_GROUP_RATES];
- tp_idx = mi->max_tp_rate[0] % MCS_GROUP_RATES;
+ tp_group = &minstrel_mcs_groups[MI_RATE_GROUP(mi->max_tp_rate[0])];
+ tp_idx = MI_RATE_IDX(mi->max_tp_rate[0]);
max_dur = minstrel_get_duration(mi->max_tp_rate[0]);
if (faster_rate)
@@ -670,7 +670,7 @@ minstrel_ht_find_probe_rates(struct minstrel_ht_sta *mi, u16 *rates, int *n_rate
if ((group->duration[i] << group->shift) > max_dur)
continue;
- idx = g * MCS_GROUP_RATES + i;
+ idx = MI_RATE(g, i);
if (idx == mi->max_tp_rate[0])
continue;
@@ -712,10 +712,10 @@ minstrel_ht_rate_sample_switch(struct minstrel_priv *mp,
/* If no suitable rate was found, try to pick the next one in the group */
if (!n_rates) {
- int g_idx = mi->max_tp_rate[0] / MCS_GROUP_RATES;
+ int g_idx = MI_RATE_GROUP(mi->max_tp_rate[0]);
u16 supported = mi->supported[g_idx];
- supported >>= mi->max_tp_rate[0] % MCS_GROUP_RATES;
+ supported >>= MI_RATE_IDX(mi->max_tp_rate[0]);
for (i = 0; supported; supported >>= 1, i++) {
if (!(supported & 1))
continue;
@@ -856,22 +856,26 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
memset(tmp_mcs_tp_rate, 0, sizeof(tmp_mcs_tp_rate));
memset(tmp_legacy_tp_rate, 0, sizeof(tmp_legacy_tp_rate));
+
if (mi->supported[MINSTREL_CCK_GROUP])
- for (j = 0; j < ARRAY_SIZE(tmp_legacy_tp_rate); j++)
- tmp_legacy_tp_rate[j] = MINSTREL_CCK_GROUP * MCS_GROUP_RATES;
+ group = MINSTREL_CCK_GROUP;
else if (mi->supported[MINSTREL_OFDM_GROUP])
- for (j = 0; j < ARRAY_SIZE(tmp_legacy_tp_rate); j++)
- tmp_legacy_tp_rate[j] = MINSTREL_OFDM_GROUP * MCS_GROUP_RATES;
+ group = MINSTREL_OFDM_GROUP;
+
+ index = MI_RATE(group, 0);
+ for (j = 0; j < ARRAY_SIZE(tmp_legacy_tp_rate); j++)
+ tmp_legacy_tp_rate[j] = index;
if (mi->supported[MINSTREL_VHT_GROUP_0])
- index = MINSTREL_VHT_GROUP_0 * MCS_GROUP_RATES;
+ group = MINSTREL_VHT_GROUP_0;
else if (ht_supported)
- index = MINSTREL_HT_GROUP_0 * MCS_GROUP_RATES;
+ group = MINSTREL_HT_GROUP_0;
else if (mi->supported[MINSTREL_CCK_GROUP])
- index = MINSTREL_CCK_GROUP * MCS_GROUP_RATES;
+ group = MINSTREL_CCK_GROUP;
else
- index = MINSTREL_OFDM_GROUP * MCS_GROUP_RATES;
+ group = MINSTREL_OFDM_GROUP;
+ index = MI_RATE(group, 0);
tmp_max_prob_rate = index;
for (j = 0; j < ARRAY_SIZE(tmp_mcs_tp_rate); j++)
tmp_mcs_tp_rate[j] = index;
@@ -888,7 +892,7 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
/* (re)Initialize group rate indexes */
for(j = 0; j < MAX_THR_RATES; j++)
- tmp_group_tp_rate[j] = MCS_GROUP_RATES * group;
+ tmp_group_tp_rate[j] = MI_RATE(group, 0);
if (group == MINSTREL_CCK_GROUP && ht_supported)
tp_rate = tmp_legacy_tp_rate;
@@ -897,7 +901,7 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
if (!(mi->supported[group] & BIT(i)))
continue;
- index = MCS_GROUP_RATES * group + i;
+ index = MI_RATE(group, i);
mrs = &mg->rates[i];
mrs->retry_updated = false;
@@ -929,13 +933,13 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
continue;
mg = &mi->groups[group];
- mg->max_group_prob_rate = MCS_GROUP_RATES * group;
+ mg->max_group_prob_rate = MI_RATE(group, 0);
for (i = 0; i < MCS_GROUP_RATES; i++) {
if (!(mi->supported[group] & BIT(i)))
continue;
- index = MCS_GROUP_RATES * group + i;
+ index = MI_RATE(group, i);
/* Find max probability rate per group and global */
minstrel_ht_set_best_prob_rate(mi, &tmp_max_prob_rate,
@@ -1022,7 +1026,7 @@ minstrel_downgrade_rate(struct minstrel_ht_sta *mi, u16 *idx, bool primary)
{
int group, orig_group;
- orig_group = group = *idx / MCS_GROUP_RATES;
+ orig_group = group = MI_RATE_GROUP(*idx);
while (group > 0) {
group--;
@@ -1206,7 +1210,7 @@ minstrel_calc_retransmit(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
ctime += (t_slot * cw) >> 1;
cw = min((cw << 1) | 1, mp->cw_max);
- if (minstrel_ht_is_legacy_group(index / MCS_GROUP_RATES)) {
+ if (minstrel_ht_is_legacy_group(MI_RATE_GROUP(index))) {
overhead = mi->overhead_legacy;
overhead_rtscts = mi->overhead_legacy_rtscts;
} else {
@@ -1239,7 +1243,7 @@ static void
minstrel_ht_set_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
struct ieee80211_sta_rates *ratetbl, int offset, int index)
{
- int group_idx = index / MCS_GROUP_RATES;
+ int group_idx = MI_RATE_GROUP(index);
const struct mcs_group *group = &minstrel_mcs_groups[group_idx];
struct minstrel_rate_stats *mrs;
u8 idx;
@@ -1259,7 +1263,7 @@ minstrel_ht_set_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
ratetbl->rate[offset].count_rts = mrs->retry_count_rtscts;
}
- index %= MCS_GROUP_RATES;
+ index = MI_RATE_IDX(index);
if (group_idx == MINSTREL_CCK_GROUP)
idx = mp->cck_rates[index % ARRAY_SIZE(mp->cck_rates)];
else if (group_idx == MINSTREL_OFDM_GROUP)
@@ -1289,17 +1293,17 @@ minstrel_ht_set_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
static inline int
minstrel_ht_get_prob_avg(struct minstrel_ht_sta *mi, int rate)
{
- int group = rate / MCS_GROUP_RATES;
- rate %= MCS_GROUP_RATES;
+ int group = MI_RATE_GROUP(rate);
+ rate = MI_RATE_IDX(rate);
return mi->groups[group].rates[rate].prob_avg;
}
static int
minstrel_ht_get_max_amsdu_len(struct minstrel_ht_sta *mi)
{
- int group = mi->max_prob_rate / MCS_GROUP_RATES;
+ int group = MI_RATE_GROUP(mi->max_prob_rate);
const struct mcs_group *g = &minstrel_mcs_groups[group];
- int rate = mi->max_prob_rate % MCS_GROUP_RATES;
+ int rate = MI_RATE_IDX(mi->max_prob_rate);
unsigned int duration;
/* Disable A-MSDU if max_prob_rate is bad */
@@ -1405,7 +1409,7 @@ minstrel_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
return -1;
mrs = &mg->rates[sample_idx];
- sample_idx += sample_group * MCS_GROUP_RATES;
+ sample_idx += MI_RATE(sample_group, 0);
tp_rate1 = mi->max_tp_rate[0];
@@ -1455,8 +1459,7 @@ minstrel_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
* if the link is working perfectly.
*/
- cur_max_tp_streams = minstrel_mcs_groups[tp_rate1 /
- MCS_GROUP_RATES].streams;
+ cur_max_tp_streams = minstrel_mcs_groups[MI_RATE_GROUP(tp_rate1)].streams;
if (sample_dur >= minstrel_get_duration(tp_rate2) &&
(cur_max_tp_streams - 1 <
minstrel_mcs_groups[sample_group].streams ||
@@ -1484,7 +1487,7 @@ minstrel_ht_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta,
int sample_idx;
if (!(info->flags & IEEE80211_TX_CTL_AMPDU) &&
- !minstrel_ht_is_legacy_group(mi->max_prob_rate / MCS_GROUP_RATES))
+ !minstrel_ht_is_legacy_group(MI_RATE_GROUP(mi->max_prob_rate)))
minstrel_aggr_check(sta, txrc->skb);
info->flags |= mi->tx_flags;
@@ -1512,8 +1515,8 @@ minstrel_ht_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta,
if (sample_idx < 0)
return;
- sample_group = &minstrel_mcs_groups[sample_idx / MCS_GROUP_RATES];
- sample_idx %= MCS_GROUP_RATES;
+ sample_group = &minstrel_mcs_groups[MI_RATE_GROUP(sample_idx)];
+ sample_idx = MI_RATE_IDX(sample_idx);
if (sample_group == &minstrel_mcs_groups[MINSTREL_CCK_GROUP] &&
(sample_idx >= 4) != txrc->short_preamble)
@@ -1529,7 +1532,7 @@ minstrel_ht_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta,
int idx = sample_idx % ARRAY_SIZE(mp->ofdm_rates[0]);
rate->idx = mp->ofdm_rates[mi->band][idx];
} else if (sample_group->flags & IEEE80211_TX_RC_VHT_MCS) {
- ieee80211_rate_set_vht(rate, sample_idx % MCS_GROUP_RATES,
+ ieee80211_rate_set_vht(rate, MI_RATE_IDX(sample_idx),
sample_group->streams);
} else {
rate->idx = sample_idx + (sample_group->streams - 1) * 8;
@@ -1898,8 +1901,8 @@ static u32 minstrel_ht_get_expected_throughput(void *priv_sta)
struct minstrel_ht_sta *mi = priv_sta;
int i, j, prob, tp_avg;
- i = mi->max_tp_rate[0] / MCS_GROUP_RATES;
- j = mi->max_tp_rate[0] % MCS_GROUP_RATES;
+ i = MI_RATE_GROUP(mi->max_tp_rate[0]);
+ j = MI_RATE_IDX(mi->max_tp_rate[0]);
prob = mi->groups[i].rates[j].prob_avg;
/* convert tp_avg from pkt per second in kbps */
diff --git a/net/mac80211/rc80211_minstrel_ht.h b/net/mac80211/rc80211_minstrel_ht.h
index 7d6d0b720f6d..5912f7dc5267 100644
--- a/net/mac80211/rc80211_minstrel_ht.h
+++ b/net/mac80211/rc80211_minstrel_ht.h
@@ -6,6 +6,8 @@
#ifndef __RC_MINSTREL_HT_H
#define __RC_MINSTREL_HT_H
+#include <linux/bitfield.h>
+
/* number of highest throughput rates to consider*/
#define MAX_THR_RATES 4
#define SAMPLE_COLUMNS 10 /* number of columns in sample table */
@@ -57,6 +59,17 @@
#define MCS_GROUP_RATES 10
+#define MI_RATE_IDX_MASK GENMASK(3, 0)
+#define MI_RATE_GROUP_MASK GENMASK(15, 4)
+
+#define MI_RATE(_group, _idx) \
+ (FIELD_PREP(MI_RATE_GROUP_MASK, _group) | \
+ FIELD_PREP(MI_RATE_IDX_MASK, _idx))
+
+#define MI_RATE_IDX(_rate) FIELD_GET(MI_RATE_IDX_MASK, _rate)
+#define MI_RATE_GROUP(_rate) FIELD_GET(MI_RATE_GROUP_MASK, _rate)
+
+
struct minstrel_priv {
struct ieee80211_hw *hw;
bool has_mrr;
diff --git a/net/mac80211/rc80211_minstrel_ht_debugfs.c b/net/mac80211/rc80211_minstrel_ht_debugfs.c
index 3b7af242cde6..067d10383fa7 100644
--- a/net/mac80211/rc80211_minstrel_ht_debugfs.c
+++ b/net/mac80211/rc80211_minstrel_ht_debugfs.c
@@ -56,7 +56,7 @@ minstrel_ht_stats_dump(struct minstrel_ht_sta *mi, int i, char *p)
for (j = 0; j < MCS_GROUP_RATES; j++) {
struct minstrel_rate_stats *mrs = &mi->groups[i].rates[j];
- int idx = i * MCS_GROUP_RATES + j;
+ int idx = MI_RATE(i, j);
unsigned int duration;
if (!(mi->supported[i] & BIT(j)))
@@ -201,7 +201,7 @@ minstrel_ht_stats_csv_dump(struct minstrel_ht_sta *mi, int i, char *p)
for (j = 0; j < MCS_GROUP_RATES; j++) {
struct minstrel_rate_stats *mrs = &mi->groups[i].rates[j];
- int idx = i * MCS_GROUP_RATES + j;
+ int idx = MI_RATE(i, j);
unsigned int duration;
if (!(mi->supported[i] & BIT(j)))
--
2.28.0
^ permalink raw reply related [flat|nested] 12+ messages in thread
* [PATCH 2/6] mac80211: minstrel_ht: update total packets counter in tx status path
2021-01-24 12:28 [PATCH 1/6] mac80211: minstrel_ht: use bitfields to encode rate indexes Felix Fietkau
@ 2021-01-24 12:28 ` Felix Fietkau
2021-01-24 12:28 ` [PATCH 3/6] mac80211: minstrel_ht: reduce the need to sample slower rates Felix Fietkau
` (4 subsequent siblings)
5 siblings, 0 replies; 12+ messages in thread
From: Felix Fietkau @ 2021-01-24 12:28 UTC (permalink / raw)
To: linux-wireless; +Cc: johannes
Keep the update in one place and prepare for further rework
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
net/mac80211/rc80211_minstrel_ht.c | 21 ++++++++++-----------
1 file changed, 10 insertions(+), 11 deletions(-)
diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c
index a3b86fd300f0..2ef748ca5355 100644
--- a/net/mac80211/rc80211_minstrel_ht.c
+++ b/net/mac80211/rc80211_minstrel_ht.c
@@ -1093,6 +1093,16 @@ minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband,
info->status.ampdu_len = 1;
}
+ /* wraparound */
+ if (mi->total_packets >= ~0 - info->status.ampdu_len) {
+ mi->total_packets = 0;
+ mi->sample_packets = 0;
+ }
+
+ mi->total_packets += info->status.ampdu_len;
+ if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE)
+ mi->sample_packets += info->status.ampdu_len;
+
mi->ampdu_packets++;
mi->ampdu_len += info->status.ampdu_len;
@@ -1104,9 +1114,6 @@ minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband,
mi->sample_count--;
}
- if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE)
- mi->sample_packets += info->status.ampdu_len;
-
if (mi->sample_mode != MINSTREL_SAMPLE_IDLE)
rate_sample = minstrel_get_ratestats(mi, mi->sample_rate);
@@ -1504,14 +1511,6 @@ minstrel_ht_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta,
else
sample_idx = minstrel_get_sample_rate(mp, mi);
- mi->total_packets++;
-
- /* wraparound */
- if (mi->total_packets == ~0) {
- mi->total_packets = 0;
- mi->sample_packets = 0;
- }
-
if (sample_idx < 0)
return;
--
2.28.0
^ permalink raw reply related [flat|nested] 12+ messages in thread
* [PATCH 3/6] mac80211: minstrel_ht: reduce the need to sample slower rates
2021-01-24 12:28 [PATCH 1/6] mac80211: minstrel_ht: use bitfields to encode rate indexes Felix Fietkau
2021-01-24 12:28 ` [PATCH 2/6] mac80211: minstrel_ht: update total packets counter in tx status path Felix Fietkau
@ 2021-01-24 12:28 ` Felix Fietkau
2021-01-24 12:28 ` [PATCH 4/6] mac80211: minstrel_ht: significantly redesign the rate probing strategy Felix Fietkau
` (3 subsequent siblings)
5 siblings, 0 replies; 12+ messages in thread
From: Felix Fietkau @ 2021-01-24 12:28 UTC (permalink / raw)
To: linux-wireless; +Cc: johannes
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>
---
net/mac80211/rc80211_minstrel_ht.c | 18 ++++++++----------
net/mac80211/rc80211_minstrel_ht.h | 2 --
2 files changed, 8 insertions(+), 12 deletions(-)
diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c
index 2ef748ca5355..22adcebb8d51 100644
--- a/net/mac80211/rc80211_minstrel_ht.c
+++ b/net/mac80211/rc80211_minstrel_ht.c
@@ -791,14 +791,11 @@ minstrel_ht_calc_rate_stats(struct minstrel_priv *mp,
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_priv *mp, struct minstrel_ht_sta *mi,
mi->ampdu_packets = 0;
}
- mi->sample_slow = 0;
mi->sample_count = 0;
memset(tmp_mcs_tp_rate, 0, sizeof(tmp_mcs_tp_rate));
@@ -883,6 +879,7 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
/* 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])
@@ -897,7 +894,7 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
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;
@@ -906,6 +903,11 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
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)
@@ -1470,13 +1472,9 @@ minstrel_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
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;
diff --git a/net/mac80211/rc80211_minstrel_ht.h b/net/mac80211/rc80211_minstrel_ht.h
index 5912f7dc5267..ebb2b88f44d9 100644
--- 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;
--
2.28.0
^ permalink raw reply related [flat|nested] 12+ messages in thread
* [PATCH 4/6] mac80211: minstrel_ht: significantly redesign the rate probing strategy
2021-01-24 12:28 [PATCH 1/6] mac80211: minstrel_ht: use bitfields to encode rate indexes Felix Fietkau
2021-01-24 12:28 ` [PATCH 2/6] mac80211: minstrel_ht: update total packets counter in tx status path Felix Fietkau
2021-01-24 12:28 ` [PATCH 3/6] mac80211: minstrel_ht: reduce the need to sample slower rates Felix Fietkau
@ 2021-01-24 12:28 ` Felix Fietkau
2021-01-25 11:56 ` Toke Høiland-Jørgensen
2021-01-24 12:28 ` [PATCH 5/6] mac80211: minstrel_ht: show sampling rates in debugfs Felix Fietkau
` (2 subsequent siblings)
5 siblings, 1 reply; 12+ messages in thread
From: Felix Fietkau @ 2021-01-24 12:28 UTC (permalink / raw)
To: linux-wireless; +Cc: johannes
The biggest flaw in current minstrel_ht is the fact that it needs way too
many probing packets to be able to quickly find the best rate.
Depending on the wifi hardware and operating mode, this can significantly
reduce throughput when not operating at the highest available data rate.
In order to be able to significantly reduce the amount of rate sampling,
we need a much smarter selection of probing rates.
The new approach introduced by this patch maintains a limited set of
available rates to be tested during a statistics window.
They are split into distinct categories:
- MINSTREL_SAMPLE_TYPE_INC - incremental rate upgrade:
Pick the next rate group and find the first rate that is faster than
the current max. throughput rate
- MINSTREL_SAMPLE_TYPE_JUMP - random testing of higher rates:
Pick a random rate from the next group that is faster than the current
max throughput rate. This allows faster adaptation when the link changes
significantly
- MINSTREL_SAMPLE_TYPE_SLOW - test a rate between max_prob, max_tp2 and
max_tp in order to reduce the gap between them
In order to prioritize sampling, every 6 attempts are split into 3x INC,
2x JUMP, 1x SLOW.
Available rates are checked and refilled on every stats window update.
With this approach, we finally get a very small delta in throughput when
comparing setting the optimal data rate as a fixed rate vs normal rate
control operation.
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
net/mac80211/rc80211_minstrel_ht.c | 550 +++++++++++++++++------------
net/mac80211/rc80211_minstrel_ht.h | 25 +-
2 files changed, 336 insertions(+), 239 deletions(-)
diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c
index 22adcebb8d51..95e10c4b1539 100644
--- a/net/mac80211/rc80211_minstrel_ht.c
+++ b/net/mac80211/rc80211_minstrel_ht.c
@@ -266,6 +266,14 @@ const struct mcs_group minstrel_mcs_groups[] = {
const s16 minstrel_cck_bitrates[4] = { 10, 20, 55, 110 };
const s16 minstrel_ofdm_bitrates[8] = { 60, 90, 120, 180, 240, 360, 480, 540 };
static u8 sample_table[SAMPLE_COLUMNS][MCS_GROUP_RATES] __read_mostly;
+static const u8 minstrel_sample_seq[] = {
+ MINSTREL_SAMPLE_TYPE_INC,
+ MINSTREL_SAMPLE_TYPE_JUMP,
+ MINSTREL_SAMPLE_TYPE_INC,
+ MINSTREL_SAMPLE_TYPE_JUMP,
+ MINSTREL_SAMPLE_TYPE_INC,
+ MINSTREL_SAMPLE_TYPE_SLOW,
+};
static void
minstrel_ht_update_rates(struct minstrel_priv *mp, struct minstrel_ht_sta *mi);
@@ -620,77 +628,31 @@ minstrel_ht_prob_rate_reduce_streams(struct minstrel_ht_sta *mi)
}
}
-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)
-{
- if (group->bw < tp_group->bw)
- return false;
-
- if (group->streams == tp_group->streams)
- return true;
-
- if (tp_idx < 4 && group->streams == tp_group->streams - 1)
- return true;
-
- return group->streams == tp_group->streams + 1;
-}
-
-static void
-minstrel_ht_find_probe_rates(struct minstrel_ht_sta *mi, u16 *rates, int *n_rates,
- bool faster_rate)
+static u16
+__minstrel_ht_get_sample_rate(struct minstrel_ht_sta *mi,
+ enum minstrel_sample_type type)
{
- const struct mcs_group *group, *tp_group;
- int i, g, max_dur;
- int tp_idx;
-
- tp_group = &minstrel_mcs_groups[MI_RATE_GROUP(mi->max_tp_rate[0])];
- tp_idx = MI_RATE_IDX(mi->max_tp_rate[0]);
-
- max_dur = minstrel_get_duration(mi->max_tp_rate[0]);
- if (faster_rate)
- max_dur -= max_dur / 16;
-
- for (g = 0; g < MINSTREL_GROUPS_NB; g++) {
- u16 supported = mi->supported[g];
-
- if (!supported)
- continue;
+ u16 *rates = mi->sample[type].sample_rates;
+ u16 cur;
+ int i;
- group = &minstrel_mcs_groups[g];
- if (!minstrel_ht_probe_group(mi, tp_group, tp_idx, group))
+ for (i = 0; i < MINSTREL_SAMPLE_RATES; i++) {
+ if (!rates[i])
continue;
- for (i = 0; supported; supported >>= 1, i++) {
- int idx;
-
- if (!(supported & 1))
- continue;
-
- if ((group->duration[i] << group->shift) > max_dur)
- continue;
-
- idx = MI_RATE(g, i);
- if (idx == mi->max_tp_rate[0])
- continue;
-
- rates[(*n_rates)++] = idx;
- break;
- }
+ cur = rates[i];
+ rates[i] = 0;
+ return cur;
}
+
+ return 0;
}
static void
minstrel_ht_rate_sample_switch(struct minstrel_priv *mp,
struct minstrel_ht_sta *mi)
{
- struct minstrel_rate_stats *mrs;
- u16 rates[MINSTREL_GROUPS_NB];
- int n_rates = 0;
- int probe_rate = 0;
- bool faster_rate;
- int i;
- u8 random;
+ u16 rate;
/*
* Use rate switching instead of probing packets for devices with
@@ -699,43 +661,11 @@ minstrel_ht_rate_sample_switch(struct minstrel_priv *mp,
if (mp->hw->max_rates > 1)
return;
- /*
- * If the current EWMA prob is >75%, look for a rate that's 6.25%
- * faster than the max tp rate.
- * If that fails, look again for a rate that is at least as fast
- */
- mrs = minstrel_get_ratestats(mi, mi->max_tp_rate[0]);
- faster_rate = mrs->prob_avg > MINSTREL_FRAC(75, 100);
- minstrel_ht_find_probe_rates(mi, rates, &n_rates, faster_rate);
- if (!n_rates && faster_rate)
- minstrel_ht_find_probe_rates(mi, rates, &n_rates, false);
-
- /* If no suitable rate was found, try to pick the next one in the group */
- if (!n_rates) {
- int g_idx = MI_RATE_GROUP(mi->max_tp_rate[0]);
- u16 supported = mi->supported[g_idx];
-
- supported >>= MI_RATE_IDX(mi->max_tp_rate[0]);
- for (i = 0; supported; supported >>= 1, i++) {
- if (!(supported & 1))
- continue;
-
- probe_rate = mi->max_tp_rate[0] + i;
- goto out;
- }
-
+ rate = __minstrel_ht_get_sample_rate(mi, MINSTREL_SAMPLE_TYPE_INC);
+ if (!rate)
return;
- }
- i = 0;
- if (n_rates > 1) {
- random = prandom_u32();
- i = random % n_rates;
- }
- probe_rate = rates[i];
-
-out:
- mi->sample_rate = probe_rate;
+ mi->sample_rate = rate;
mi->sample_mode = MINSTREL_SAMPLE_ACTIVE;
}
@@ -804,6 +734,274 @@ minstrel_ht_calc_rate_stats(struct minstrel_priv *mp,
mrs->attempts = 0;
}
+static bool
+minstrel_ht_find_sample_rate(struct minstrel_ht_sta *mi, int type, int idx)
+{
+ int i;
+
+ for (i = 0; i < MINSTREL_SAMPLE_RATES; i++) {
+ u16 cur = mi->sample[type].sample_rates[i];
+
+ if (cur == idx)
+ return true;
+
+ if (!cur)
+ break;
+ }
+
+ return false;
+}
+
+static int
+minstrel_ht_move_sample_rates(struct minstrel_ht_sta *mi, int type,
+ u32 fast_rate_dur, u32 slow_rate_dur)
+{
+ u16 *rates = mi->sample[type].sample_rates;
+ int i, j;
+
+ for (i = 0, j = 0; i < MINSTREL_SAMPLE_RATES; i++) {
+ u32 duration;
+ bool valid = false;
+ u16 cur;
+
+ cur = rates[i];
+ if (!cur)
+ continue;
+
+ duration = minstrel_get_duration(cur);
+ switch (type) {
+ case MINSTREL_SAMPLE_TYPE_SLOW:
+ valid = duration > fast_rate_dur &&
+ duration < slow_rate_dur;
+ break;
+ case MINSTREL_SAMPLE_TYPE_INC:
+ case MINSTREL_SAMPLE_TYPE_JUMP:
+ valid = duration < fast_rate_dur;
+ break;
+ default:
+ valid = false;
+ break;
+ }
+
+ if (!valid) {
+ rates[i] = 0;
+ continue;
+ }
+
+ if (i == j)
+ continue;
+
+ rates[j++] = cur;
+ rates[i] = 0;
+ }
+
+ return j;
+}
+
+static int
+minstrel_ht_group_min_rate_offset(struct minstrel_ht_sta *mi, int group,
+ u32 max_duration)
+{
+ u16 supported = mi->supported[group];
+ int i;
+
+ for (i = 0; i < MCS_GROUP_RATES && supported; i++, supported >>= 1) {
+ if (!(supported & BIT(0)))
+ continue;
+
+ if (minstrel_get_duration(MI_RATE(group, i)) >= max_duration)
+ continue;
+
+ return i;
+ }
+
+ return -1;
+}
+
+/*
+ * Incremental update rates:
+ * Flip through groups and pick the first group rate that is faster than the
+ * highest currently selected rate
+ */
+static u16
+minstrel_ht_next_inc_rate(struct minstrel_ht_sta *mi, u32 fast_rate_dur)
+{
+ struct minstrel_mcs_group_data *mg;
+ u8 type = MINSTREL_SAMPLE_TYPE_INC;
+ int i, index = 0;
+ u8 group;
+
+ group = mi->sample[type].sample_group;
+ for (i = 0; i < ARRAY_SIZE(minstrel_mcs_groups); i++) {
+ group = (group + 1) % ARRAY_SIZE(minstrel_mcs_groups);
+ mg = &mi->groups[group];
+
+ index = minstrel_ht_group_min_rate_offset(mi, group,
+ fast_rate_dur);
+ if (index < 0)
+ continue;
+
+ index = MI_RATE(group, index & 0xf);
+ if (!minstrel_ht_find_sample_rate(mi, type, index))
+ goto out;
+ }
+ index = 0;
+
+out:
+ mi->sample[type].sample_group = group;
+
+ return index;
+}
+
+static int
+minstrel_ht_next_group_sample_rate(struct minstrel_ht_sta *mi, int group,
+ u16 supported, int offset)
+{
+ struct minstrel_mcs_group_data *mg = &mi->groups[group];
+ u16 idx;
+ int i;
+
+ for (i = 0; i < MCS_GROUP_RATES; i++) {
+ idx = sample_table[mg->column][mg->index];
+ if (++mg->index >= MCS_GROUP_RATES) {
+ mg->index = 0;
+ if (++mg->column >= ARRAY_SIZE(sample_table))
+ mg->column = 0;
+ }
+
+ if (idx < offset)
+ continue;
+
+ if (!(supported & BIT(idx)))
+ continue;
+
+ return MI_RATE(group, idx);
+ }
+
+ return -1;
+}
+
+/*
+ * Jump rates:
+ * Sample random rates, use those that are faster than the highest
+ * currently selected rate. Rates between the fastest and the slowest
+ * get sorted into the slow sample bucket, but only if it has room
+ */
+static u16
+minstrel_ht_next_jump_rate(struct minstrel_ht_sta *mi, u32 fast_rate_dur,
+ u32 slow_rate_dur, int *slow_rate_ofs)
+{
+ struct minstrel_mcs_group_data *mg;
+ struct minstrel_rate_stats *mrs;
+ u32 max_duration = slow_rate_dur;
+ int i, index, offset;
+ u16 *slow_rates;
+ u16 supported;
+ u32 duration;
+ u8 group;
+
+ if (*slow_rate_ofs >= MINSTREL_SAMPLE_RATES)
+ max_duration = fast_rate_dur;
+
+ slow_rates = mi->sample[MINSTREL_SAMPLE_TYPE_SLOW].sample_rates;
+ group = mi->sample[MINSTREL_SAMPLE_TYPE_JUMP].sample_group;
+ for (i = 0; i < ARRAY_SIZE(minstrel_mcs_groups); i++) {
+ u8 type;
+
+ group = (group + 1) % ARRAY_SIZE(minstrel_mcs_groups);
+ mg = &mi->groups[group];
+
+ supported = mi->supported[group];
+ if (!supported)
+ continue;
+
+ offset = minstrel_ht_group_min_rate_offset(mi, group,
+ max_duration);
+ if (offset < 0)
+ continue;
+
+ index = minstrel_ht_next_group_sample_rate(mi, group, supported,
+ offset);
+ if (index < 0)
+ continue;
+
+ duration = minstrel_get_duration(index);
+ if (duration < fast_rate_dur)
+ type = MINSTREL_SAMPLE_TYPE_JUMP;
+ else
+ type = MINSTREL_SAMPLE_TYPE_SLOW;
+
+ if (minstrel_ht_find_sample_rate(mi, type, index))
+ continue;
+
+ if (type == MINSTREL_SAMPLE_TYPE_JUMP)
+ goto found;
+
+ if (*slow_rate_ofs >= MINSTREL_SAMPLE_RATES)
+ continue;
+
+ if (duration >= slow_rate_dur)
+ continue;
+
+ /* skip slow rates with high success probability */
+ mrs = minstrel_get_ratestats(mi, index);
+ if (mrs->prob_avg > MINSTREL_FRAC(95, 100))
+ continue;
+
+ slow_rates[(*slow_rate_ofs)++] = index;
+ if (*slow_rate_ofs >= MINSTREL_SAMPLE_RATES)
+ max_duration = fast_rate_dur;
+ }
+ index = 0;
+
+found:
+ mi->sample[MINSTREL_SAMPLE_TYPE_JUMP].sample_group = group;
+
+ return index;
+}
+
+static void
+minstrel_ht_refill_sample_rates(struct minstrel_ht_sta *mi)
+{
+ u32 prob_dur = minstrel_get_duration(mi->max_prob_rate);
+ u32 tp_dur = minstrel_get_duration(mi->max_tp_rate[0]);
+ u32 tp2_dur = minstrel_get_duration(mi->max_tp_rate[1]);
+ u32 fast_rate_dur = min(min(tp_dur, tp2_dur), prob_dur);
+ u32 slow_rate_dur = max(max(tp_dur, tp2_dur), prob_dur);
+ u16 *rates;
+ int i, j;
+
+ rates = mi->sample[MINSTREL_SAMPLE_TYPE_INC].sample_rates;
+ i = minstrel_ht_move_sample_rates(mi, MINSTREL_SAMPLE_TYPE_INC,
+ fast_rate_dur, slow_rate_dur);
+ while (i < MINSTREL_SAMPLE_RATES) {
+ rates[i] = minstrel_ht_next_inc_rate(mi, tp_dur);
+ if (!rates[i])
+ break;
+
+ i++;
+ }
+
+ rates = mi->sample[MINSTREL_SAMPLE_TYPE_JUMP].sample_rates;
+ i = minstrel_ht_move_sample_rates(mi, MINSTREL_SAMPLE_TYPE_JUMP,
+ fast_rate_dur, slow_rate_dur);
+ j = minstrel_ht_move_sample_rates(mi, MINSTREL_SAMPLE_TYPE_SLOW,
+ fast_rate_dur, slow_rate_dur);
+ while (i < MINSTREL_SAMPLE_RATES) {
+ rates[i] = minstrel_ht_next_jump_rate(mi, fast_rate_dur,
+ slow_rate_dur, &j);
+ if (!rates[i])
+ break;
+
+ i++;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(mi->sample); i++)
+ memcpy(mi->sample[i].cur_sample_rates, mi->sample[i].sample_rates,
+ sizeof(mi->sample[i].cur_sample_rates));
+}
+
+
/*
* Update rate statistics and select new primary rates
*
@@ -848,8 +1046,6 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
mi->ampdu_packets = 0;
}
- mi->sample_count = 0;
-
memset(tmp_mcs_tp_rate, 0, sizeof(tmp_mcs_tp_rate));
memset(tmp_legacy_tp_rate, 0, sizeof(tmp_legacy_tp_rate));
@@ -885,8 +1081,6 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
if (!mi->supported[group])
continue;
- mi->sample_count++;
-
/* (re)Initialize group rate indexes */
for(j = 0; j < MAX_THR_RATES; j++)
tmp_group_tp_rate[j] = MI_RATE(group, 0);
@@ -953,9 +1147,7 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
/* Try to increase robustness of max_prob_rate*/
minstrel_ht_prob_rate_reduce_streams(mi);
-
- /* try to sample half of all available rates during each interval */
- mi->sample_count *= 4;
+ minstrel_ht_refill_sample_rates(mi);
if (sample)
minstrel_ht_rate_sample_switch(mp, mi);
@@ -972,6 +1164,7 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
/* Reset update timer */
mi->last_stats_update = jiffies;
+ mi->sample_time = jiffies;
}
static bool
@@ -1001,28 +1194,6 @@ minstrel_ht_txstat_valid(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
return false;
}
-static void
-minstrel_set_next_sample_idx(struct minstrel_ht_sta *mi)
-{
- struct minstrel_mcs_group_data *mg;
-
- for (;;) {
- mi->sample_group++;
- mi->sample_group %= ARRAY_SIZE(minstrel_mcs_groups);
- mg = &mi->groups[mi->sample_group];
-
- if (!mi->supported[mi->sample_group])
- continue;
-
- if (++mg->index >= MCS_GROUP_RATES) {
- mg->index = 0;
- if (++mg->column >= ARRAY_SIZE(sample_table))
- mg->column = 0;
- }
- break;
- }
-}
-
static void
minstrel_downgrade_rate(struct minstrel_ht_sta *mi, u16 *idx, bool primary)
{
@@ -1108,14 +1279,6 @@ minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband,
mi->ampdu_packets++;
mi->ampdu_len += info->status.ampdu_len;
- if (!mi->sample_wait && !mi->sample_tries && mi->sample_count > 0) {
- int avg_ampdu_len = minstrel_ht_avg_ampdu_len(mi);
-
- mi->sample_wait = 16 + 2 * avg_ampdu_len;
- mi->sample_tries = 1;
- mi->sample_count--;
- }
-
if (mi->sample_mode != MINSTREL_SAMPLE_IDLE)
rate_sample = minstrel_get_ratestats(mi, mi->sample_rate);
@@ -1387,97 +1550,20 @@ minstrel_ht_update_rates(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
rate_control_set_rates(mp->hw, mi->sta, rates);
}
-static int
-minstrel_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
+static u16
+minstrel_ht_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
{
- 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 (mp->hw->max_rates == 1 && mp->sample_switch &&
- (mi->total_packets_cur >= SAMPLE_SWITCH_THR ||
- mp->sample_switch == 1))
- return -1;
+ u8 seq;
- if (mi->sample_wait > 0) {
- mi->sample_wait--;
- return -1;
- }
-
- if (!mi->sample_tries)
- return -1;
-
- sample_group = mi->sample_group;
- mg = &mi->groups[sample_group];
- sample_idx = sample_table[mg->column][mg->index];
- minstrel_set_next_sample_idx(mi);
-
- if (!(mi->supported[sample_group] & BIT(sample_idx)))
- return -1;
-
- mrs = &mg->rates[sample_idx];
- sample_idx += MI_RATE(sample_group, 0);
-
- tp_rate1 = mi->max_tp_rate[0];
-
- /* Set tp_rate2 to the second highest max_tp_rate */
- if (minstrel_get_duration(mi->max_tp_rate[0]) >
- minstrel_get_duration(mi->max_tp_rate[1])) {
- tp_rate2 = mi->max_tp_rate[0];
+ if (mp->hw->max_rates > 1) {
+ seq = mi->sample_seq;
+ mi->sample_seq = (seq + 1) % ARRAY_SIZE(minstrel_sample_seq);
+ seq = minstrel_sample_seq[seq];
} else {
- tp_rate2 = mi->max_tp_rate[1];
+ seq = MINSTREL_SAMPLE_TYPE_INC;
}
- /*
- * Sampling might add some overhead (RTS, no aggregation)
- * 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_prob_rate)
- return -1;
-
- /*
- * Do not sample if the probability is already higher than 95%,
- * or if the rate is 3 times slower than the current max probability
- * rate, to avoid wasting airtime.
- */
- sample_dur = minstrel_get_duration(sample_idx);
- if (mrs->prob_avg > MINSTREL_FRAC(95, 100) ||
- minstrel_get_duration(mi->max_prob_rate) * 3 < sample_dur)
- return -1;
-
-
- /*
- * For devices with no configurable multi-rate retry, skip sampling
- * below the per-group max throughput rate, and only use one sampling
- * attempt per rate
- */
- if (mp->hw->max_rates == 1 &&
- (minstrel_get_duration(mg->max_group_tp_rate[0]) < sample_dur ||
- mrs->attempts))
- return -1;
-
- /* Skip already sampled slow rates */
- if (sample_dur >= minstrel_get_duration(tp_rate1) && mrs->attempts)
- return -1;
-
- /*
- * Make sure that lower rates get sampled only occasionally,
- * if the link is working perfectly.
- */
-
- cur_max_tp_streams = minstrel_mcs_groups[MI_RATE_GROUP(tp_rate1)].streams;
- 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)))
- return -1;
-
- mi->sample_tries--;
-
- return sample_idx;
+ return __minstrel_ht_get_sample_rate(mi, seq);
}
static void
@@ -1489,7 +1575,7 @@ minstrel_ht_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta,
struct ieee80211_tx_rate *rate = &info->status.rates[0];
struct minstrel_ht_sta *mi = priv_sta;
struct minstrel_priv *mp = priv;
- int sample_idx;
+ u16 sample_idx;
if (!(info->flags & IEEE80211_TX_CTL_AMPDU) &&
!minstrel_ht_is_legacy_group(MI_RATE_GROUP(mi->max_prob_rate)))
@@ -1505,11 +1591,19 @@ minstrel_ht_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta,
/* Don't use EAPOL frames for sampling on non-mrr hw */
if (mp->hw->max_rates == 1 &&
(info->control.flags & IEEE80211_TX_CTRL_PORT_CTRL_PROTO))
- sample_idx = -1;
- else
- sample_idx = minstrel_get_sample_rate(mp, mi);
+ return;
+
+ if (mp->hw->max_rates == 1 && mp->sample_switch &&
+ (mi->total_packets_cur >= SAMPLE_SWITCH_THR ||
+ mp->sample_switch == 1))
+ return;
+
+ if (time_is_before_jiffies(mi->sample_time))
+ return;
- if (sample_idx < 0)
+ mi->sample_time = jiffies + MINSTREL_SAMPLE_INTERVAL;
+ sample_idx = minstrel_ht_get_sample_rate(mp, mi);
+ if (!sample_idx)
return;
sample_group = &minstrel_mcs_groups[MI_RATE_GROUP(sample_idx)];
@@ -1630,16 +1724,6 @@ minstrel_ht_update_caps(void *priv, struct ieee80211_supported_band *sband,
mi->avg_ampdu_len = MINSTREL_FRAC(1, 1);
- /* When using MRR, sample more on the first attempt, without delay */
- if (mp->has_mrr) {
- mi->sample_count = 16;
- mi->sample_wait = 0;
- } else {
- mi->sample_count = 8;
- mi->sample_wait = 8;
- }
- mi->sample_tries = 4;
-
if (!use_vht) {
stbc = (ht_cap & IEEE80211_HT_CAP_RX_STBC) >>
IEEE80211_HT_CAP_RX_STBC_SHIFT;
diff --git a/net/mac80211/rc80211_minstrel_ht.h b/net/mac80211/rc80211_minstrel_ht.h
index ebb2b88f44d9..0d8c15f83f5d 100644
--- a/net/mac80211/rc80211_minstrel_ht.h
+++ b/net/mac80211/rc80211_minstrel_ht.h
@@ -69,6 +69,8 @@
#define MI_RATE_IDX(_rate) FIELD_GET(MI_RATE_IDX_MASK, _rate)
#define MI_RATE_GROUP(_rate) FIELD_GET(MI_RATE_GROUP_MASK, _rate)
+#define MINSTREL_SAMPLE_RATES 5 /* rates per sample type */
+#define MINSTREL_SAMPLE_INTERVAL (HZ / 50)
struct minstrel_priv {
struct ieee80211_hw *hw;
@@ -126,6 +128,13 @@ struct minstrel_rate_stats {
bool retry_updated;
};
+enum minstrel_sample_type {
+ MINSTREL_SAMPLE_TYPE_INC,
+ MINSTREL_SAMPLE_TYPE_JUMP,
+ MINSTREL_SAMPLE_TYPE_SLOW,
+ __MINSTREL_SAMPLE_TYPE_MAX
+};
+
struct minstrel_mcs_group_data {
u8 index;
u8 column;
@@ -144,6 +153,12 @@ enum minstrel_sample_mode {
MINSTREL_SAMPLE_PENDING,
};
+struct minstrel_sample_category {
+ u8 sample_group;
+ u16 sample_rates[MINSTREL_SAMPLE_RATES];
+ u16 cur_sample_rates[MINSTREL_SAMPLE_RATES];
+};
+
struct minstrel_ht_sta {
struct ieee80211_sta *sta;
@@ -175,16 +190,14 @@ struct minstrel_ht_sta {
/* tx flags to add for frames for this sta */
u32 tx_flags;
- u8 sample_wait;
- u8 sample_tries;
- u8 sample_count;
+ unsigned long sample_time;
+ struct minstrel_sample_category sample[__MINSTREL_SAMPLE_TYPE_MAX];
+
+ u8 sample_seq;
enum minstrel_sample_mode sample_mode;
u16 sample_rate;
- /* current MCS group to be sampled */
- u8 sample_group;
-
u8 band;
/* Bitfield of supported MCS rates of all groups */
--
2.28.0
^ permalink raw reply related [flat|nested] 12+ messages in thread
* [PATCH 5/6] mac80211: minstrel_ht: show sampling rates in debugfs
2021-01-24 12:28 [PATCH 1/6] mac80211: minstrel_ht: use bitfields to encode rate indexes Felix Fietkau
` (2 preceding siblings ...)
2021-01-24 12:28 ` [PATCH 4/6] mac80211: minstrel_ht: significantly redesign the rate probing strategy Felix Fietkau
@ 2021-01-24 12:28 ` Felix Fietkau
2021-01-24 12:28 ` [PATCH 6/6] mac80211: minstrel_ht: remove sample rate switching code for constrained devices Felix Fietkau
2021-01-25 19:25 ` kernel test robot
5 siblings, 0 replies; 12+ messages in thread
From: Felix Fietkau @ 2021-01-24 12:28 UTC (permalink / raw)
To: linux-wireless; +Cc: johannes
This makes it easier to see what rates are going to be tested next
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
net/mac80211/rc80211_minstrel_ht_debugfs.c | 19 +++++++++++++++++--
1 file changed, 17 insertions(+), 2 deletions(-)
diff --git a/net/mac80211/rc80211_minstrel_ht_debugfs.c b/net/mac80211/rc80211_minstrel_ht_debugfs.c
index 067d10383fa7..07aa877652a4 100644
--- a/net/mac80211/rc80211_minstrel_ht_debugfs.c
+++ b/net/mac80211/rc80211_minstrel_ht_debugfs.c
@@ -32,6 +32,18 @@ minstrel_stats_release(struct inode *inode, struct file *file)
return 0;
}
+static bool
+minstrel_ht_is_sample_rate(struct minstrel_ht_sta *mi, int idx)
+{
+ int type, i;
+
+ for (type = 0; type < ARRAY_SIZE(mi->sample); type++)
+ for (i = 0; i < MINSTREL_SAMPLE_RATES; i++)
+ if (mi->sample[type].cur_sample_rates[i] == idx)
+ return true;
+ return false;
+}
+
static char *
minstrel_ht_stats_dump(struct minstrel_ht_sta *mi, int i, char *p)
{
@@ -84,6 +96,7 @@ minstrel_ht_stats_dump(struct minstrel_ht_sta *mi, int i, char *p)
*(p++) = (idx == mi->max_tp_rate[2]) ? 'C' : ' ';
*(p++) = (idx == mi->max_tp_rate[3]) ? 'D' : ' ';
*(p++) = (idx == mi->max_prob_rate) ? 'P' : ' ';
+ *(p++) = minstrel_ht_is_sample_rate(mi, idx) ? 'S' : ' ';
if (gflags & IEEE80211_TX_RC_MCS) {
p += sprintf(p, " MCS%-2u", (mg->streams - 1) * 8 + j);
@@ -145,9 +158,9 @@ minstrel_ht_stats_open(struct inode *inode, struct file *file)
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)] [retry|suc|att] [#success | #attempts]\n");
+ "mode guard # rate [name idx airtime max_tp] [avg(tp) avg(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++)
@@ -228,6 +241,8 @@ minstrel_ht_stats_csv_dump(struct minstrel_ht_sta *mi, int i, char *p)
p += sprintf(p, "%s" ,((idx == mi->max_tp_rate[2]) ? "C" : ""));
p += sprintf(p, "%s" ,((idx == mi->max_tp_rate[3]) ? "D" : ""));
p += sprintf(p, "%s" ,((idx == mi->max_prob_rate) ? "P" : ""));
+ p += sprintf(p, "%s" ,((idx == mi->max_prob_rate) ? "P" : ""));
+ p += sprintf(p, "%s", (minstrel_ht_is_sample_rate(mi, idx) ? "S" : ""));
if (gflags & IEEE80211_TX_RC_MCS) {
p += sprintf(p, ",MCS%-2u,", (mg->streams - 1) * 8 + j);
--
2.28.0
^ permalink raw reply related [flat|nested] 12+ messages in thread
* [PATCH 6/6] mac80211: minstrel_ht: remove sample rate switching code for constrained devices
2021-01-24 12:28 [PATCH 1/6] mac80211: minstrel_ht: use bitfields to encode rate indexes Felix Fietkau
` (3 preceding siblings ...)
2021-01-24 12:28 ` [PATCH 5/6] mac80211: minstrel_ht: show sampling rates in debugfs Felix Fietkau
@ 2021-01-24 12:28 ` Felix Fietkau
2021-01-25 19:25 ` kernel test robot
5 siblings, 0 replies; 12+ messages in thread
From: Felix Fietkau @ 2021-01-24 12:28 UTC (permalink / raw)
To: linux-wireless; +Cc: johannes
This was added to mitigate the effects of too much sampling on devices that
use a static global fallback table instead of configurable multi-rate retry.
Now that the sampling algorithm is improved, this code path no longer performs
any better than the standard probing on affected devices.
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
net/mac80211/rc80211_minstrel_ht.c | 95 ++----------------------------
net/mac80211/rc80211_minstrel_ht.h | 17 +-----
2 files changed, 9 insertions(+), 103 deletions(-)
diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c
index 95e10c4b1539..8e9e30c468a6 100644
--- a/net/mac80211/rc80211_minstrel_ht.c
+++ b/net/mac80211/rc80211_minstrel_ht.c
@@ -648,27 +648,6 @@ __minstrel_ht_get_sample_rate(struct minstrel_ht_sta *mi,
return 0;
}
-static void
-minstrel_ht_rate_sample_switch(struct minstrel_priv *mp,
- struct minstrel_ht_sta *mi)
-{
- u16 rate;
-
- /*
- * Use rate switching instead of probing packets for devices with
- * little control over retry fallback behavior
- */
- if (mp->hw->max_rates > 1)
- return;
-
- rate = __minstrel_ht_get_sample_rate(mi, MINSTREL_SAMPLE_TYPE_INC);
- if (!rate)
- return;
-
- mi->sample_rate = rate;
- mi->sample_mode = MINSTREL_SAMPLE_ACTIVE;
-}
-
static inline int
minstrel_ewma(int old, int new, int weight)
{
@@ -1012,8 +991,7 @@ minstrel_ht_refill_sample_rates(struct minstrel_ht_sta *mi)
* higher throughput rates, even if the probablity is a bit lower
*/
static void
-minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
- bool sample)
+minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
{
struct minstrel_mcs_group_data *mg;
struct minstrel_rate_stats *mrs;
@@ -1023,18 +1001,6 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
u16 index;
bool ht_supported = mi->sta->ht_cap.ht_supported;
- mi->sample_mode = MINSTREL_SAMPLE_IDLE;
-
- if (sample) {
- mi->total_packets_cur = mi->total_packets -
- mi->total_packets_last;
- mi->total_packets_last = mi->total_packets;
- }
- if (!mp->sample_switch)
- sample = false;
- if (mi->total_packets_cur < SAMPLE_SWITCH_THR && mp->sample_switch != 1)
- sample = false;
-
if (mi->ampdu_packets > 0) {
if (!ieee80211_hw_check(mp->hw, TX_STATUS_NO_AMPDU_LEN))
mi->avg_ampdu_len = minstrel_ewma(mi->avg_ampdu_len,
@@ -1149,16 +1115,12 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
minstrel_ht_prob_rate_reduce_streams(mi);
minstrel_ht_refill_sample_rates(mi);
- if (sample)
- minstrel_ht_rate_sample_switch(mp, mi);
-
#ifdef CONFIG_MAC80211_DEBUGFS
/* use fixed index if set */
if (mp->fixed_rate_idx != -1) {
for (i = 0; i < 4; i++)
mi->max_tp_rate[i] = mp->fixed_rate_idx;
mi->max_prob_rate = mp->fixed_rate_idx;
- mi->sample_mode = MINSTREL_SAMPLE_IDLE;
}
#endif
@@ -1248,11 +1210,10 @@ minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband,
struct ieee80211_tx_info *info = st->info;
struct minstrel_ht_sta *mi = priv_sta;
struct ieee80211_tx_rate *ar = info->status.rates;
- struct minstrel_rate_stats *rate, *rate2, *rate_sample = NULL;
+ struct minstrel_rate_stats *rate, *rate2;
struct minstrel_priv *mp = priv;
u32 update_interval = mp->update_interval;
bool last, update = false;
- bool sample_status = false;
int i;
/* This packet was aggregated but doesn't carry status info */
@@ -1279,49 +1240,18 @@ minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband,
mi->ampdu_packets++;
mi->ampdu_len += info->status.ampdu_len;
- if (mi->sample_mode != MINSTREL_SAMPLE_IDLE)
- rate_sample = minstrel_get_ratestats(mi, mi->sample_rate);
-
last = !minstrel_ht_txstat_valid(mp, mi, &ar[0]);
for (i = 0; !last; i++) {
last = (i == IEEE80211_TX_MAX_RATES - 1) ||
!minstrel_ht_txstat_valid(mp, mi, &ar[i + 1]);
rate = minstrel_ht_get_stats(mp, mi, &ar[i]);
- if (rate == rate_sample)
- sample_status = true;
-
if (last)
rate->success += info->status.ampdu_ack_len;
rate->attempts += ar[i].count * info->status.ampdu_len;
}
- switch (mi->sample_mode) {
- case MINSTREL_SAMPLE_IDLE:
- if (mp->hw->max_rates > 1 ||
- mi->total_packets_cur < SAMPLE_SWITCH_THR)
- update_interval /= 2;
- break;
-
- case MINSTREL_SAMPLE_ACTIVE:
- if (!sample_status)
- break;
-
- mi->sample_mode = MINSTREL_SAMPLE_PENDING;
- update = true;
- break;
-
- case MINSTREL_SAMPLE_PENDING:
- if (sample_status)
- break;
-
- update = true;
- minstrel_ht_update_stats(mp, mi, false);
- break;
- }
-
-
if (mp->hw->max_rates > 1) {
/*
* check for sudden death of spatial multiplexing,
@@ -1344,7 +1274,7 @@ minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband,
if (time_after(jiffies, mi->last_stats_update + update_interval)) {
update = true;
- minstrel_ht_update_stats(mp, mi, true);
+ minstrel_ht_update_stats(mp, mi);
}
if (update)
@@ -1523,18 +1453,14 @@ static void
minstrel_ht_update_rates(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
{
struct ieee80211_sta_rates *rates;
- u16 first_rate = mi->max_tp_rate[0];
int i = 0;
- if (mi->sample_mode == MINSTREL_SAMPLE_ACTIVE)
- first_rate = mi->sample_rate;
-
rates = kzalloc(sizeof(*rates), GFP_ATOMIC);
if (!rates)
return;
/* Start with max_tp_rate[0] */
- minstrel_ht_set_rate(mp, mi, rates, i++, first_rate);
+ minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_tp_rate[0]);
if (mp->hw->max_rates >= 3) {
/* At least 3 tx rates supported, use max_tp_rate[1] next */
@@ -1593,11 +1519,6 @@ minstrel_ht_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta,
(info->control.flags & IEEE80211_TX_CTRL_PORT_CTRL_PROTO))
return;
- if (mp->hw->max_rates == 1 && mp->sample_switch &&
- (mi->total_packets_cur >= SAMPLE_SWITCH_THR ||
- mp->sample_switch == 1))
- return;
-
if (time_is_before_jiffies(mi->sample_time))
return;
@@ -1811,7 +1732,7 @@ minstrel_ht_update_caps(void *priv, struct ieee80211_supported_band *sband,
minstrel_ht_update_ofdm(mp, mi, sband, sta);
/* create an initial rate table with the lowest supported rates */
- minstrel_ht_update_stats(mp, mi, true);
+ minstrel_ht_update_stats(mp, mi);
minstrel_ht_update_rates(mp, mi);
}
@@ -1927,8 +1848,6 @@ minstrel_ht_alloc(struct ieee80211_hw *hw)
if (!mp)
return NULL;
- mp->sample_switch = -1;
-
/* contention window settings
* Just an approximation. Using the per-queue values would complicate
* the calculations and is probably unnecessary */
@@ -1948,7 +1867,7 @@ minstrel_ht_alloc(struct ieee80211_hw *hw)
mp->has_mrr = true;
mp->hw = hw;
- mp->update_interval = HZ / 10;
+ mp->update_interval = HZ / 20;
minstrel_ht_init_cck_rates(mp);
for (i = 0; i < ARRAY_SIZE(mp->hw->wiphy->bands); i++)
@@ -1966,8 +1885,6 @@ static void minstrel_ht_add_debugfs(struct ieee80211_hw *hw, void *priv,
mp->fixed_rate_idx = (u32) -1;
debugfs_create_u32("fixed_rate_idx", S_IRUGO | S_IWUGO, debugfsdir,
&mp->fixed_rate_idx);
- debugfs_create_u32("sample_switch", S_IRUGO | S_IWUSR, debugfsdir,
- &mp->sample_switch);
}
#endif
diff --git a/net/mac80211/rc80211_minstrel_ht.h b/net/mac80211/rc80211_minstrel_ht.h
index 0d8c15f83f5d..06e7126727ad 100644
--- a/net/mac80211/rc80211_minstrel_ht.h
+++ b/net/mac80211/rc80211_minstrel_ht.h
@@ -75,7 +75,6 @@
struct minstrel_priv {
struct ieee80211_hw *hw;
bool has_mrr;
- u32 sample_switch;
unsigned int cw_min;
unsigned int cw_max;
unsigned int max_retry;
@@ -147,12 +146,6 @@ struct minstrel_mcs_group_data {
struct minstrel_rate_stats rates[MCS_GROUP_RATES];
};
-enum minstrel_sample_mode {
- MINSTREL_SAMPLE_IDLE,
- MINSTREL_SAMPLE_ACTIVE,
- MINSTREL_SAMPLE_PENDING,
-};
-
struct minstrel_sample_category {
u8 sample_group;
u16 sample_rates[MINSTREL_SAMPLE_RATES];
@@ -182,23 +175,19 @@ struct minstrel_ht_sta {
unsigned int overhead_legacy;
unsigned int overhead_legacy_rtscts;
- unsigned int total_packets_last;
- unsigned int total_packets_cur;
unsigned int total_packets;
unsigned int sample_packets;
/* tx flags to add for frames for this sta */
u32 tx_flags;
- unsigned long sample_time;
- struct minstrel_sample_category sample[__MINSTREL_SAMPLE_TYPE_MAX];
+ u8 band;
u8 sample_seq;
-
- enum minstrel_sample_mode sample_mode;
u16 sample_rate;
- u8 band;
+ unsigned long sample_time;
+ struct minstrel_sample_category sample[__MINSTREL_SAMPLE_TYPE_MAX];
/* Bitfield of supported MCS rates of all groups */
u16 supported[MINSTREL_GROUPS_NB];
--
2.28.0
^ permalink raw reply related [flat|nested] 12+ messages in thread
* Re: [PATCH 4/6] mac80211: minstrel_ht: significantly redesign the rate probing strategy
2021-01-24 12:28 ` [PATCH 4/6] mac80211: minstrel_ht: significantly redesign the rate probing strategy Felix Fietkau
@ 2021-01-25 11:56 ` Toke Høiland-Jørgensen
2021-01-25 20:46 ` Felix Fietkau
0 siblings, 1 reply; 12+ messages in thread
From: Toke Høiland-Jørgensen @ 2021-01-25 11:56 UTC (permalink / raw)
To: Felix Fietkau, linux-wireless; +Cc: johannes
Felix Fietkau <nbd@nbd.name> writes:
> The biggest flaw in current minstrel_ht is the fact that it needs way too
> many probing packets to be able to quickly find the best rate.
> Depending on the wifi hardware and operating mode, this can significantly
> reduce throughput when not operating at the highest available data rate.
>
> In order to be able to significantly reduce the amount of rate sampling,
> we need a much smarter selection of probing rates.
>
> The new approach introduced by this patch maintains a limited set of
> available rates to be tested during a statistics window.
>
> They are split into distinct categories:
> - MINSTREL_SAMPLE_TYPE_INC - incremental rate upgrade:
> Pick the next rate group and find the first rate that is faster than
> the current max. throughput rate
> - MINSTREL_SAMPLE_TYPE_JUMP - random testing of higher rates:
> Pick a random rate from the next group that is faster than the current
> max throughput rate. This allows faster adaptation when the link changes
> significantly
> - MINSTREL_SAMPLE_TYPE_SLOW - test a rate between max_prob, max_tp2 and
> max_tp in order to reduce the gap between them
>
> In order to prioritize sampling, every 6 attempts are split into 3x INC,
> 2x JUMP, 1x SLOW.
>
> Available rates are checked and refilled on every stats window update.
Very cool!
> With this approach, we finally get a very small delta in throughput when
> comparing setting the optimal data rate as a fixed rate vs normal rate
> control operation.
Can you quantify this "very small delta"? Would love to see some
benchmark data :)
-Toke
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH 1/6] mac80211: minstrel_ht: use bitfields to encode rate indexes
2021-01-24 12:28 [PATCH 1/6] mac80211: minstrel_ht: use bitfields to encode rate indexes Felix Fietkau
@ 2021-01-25 19:25 ` kernel test robot
2021-01-24 12:28 ` [PATCH 3/6] mac80211: minstrel_ht: reduce the need to sample slower rates Felix Fietkau
` (4 subsequent siblings)
5 siblings, 0 replies; 12+ messages in thread
From: kernel test robot @ 2021-01-25 19:25 UTC (permalink / raw)
To: Felix Fietkau, linux-wireless; +Cc: kbuild-all, clang-built-linux, johannes
[-- Attachment #1: Type: text/plain, Size: 14496 bytes --]
Hi Felix,
I love your patch! Perhaps something to improve:
[auto build test WARNING on mac80211-next/master]
[also build test WARNING on next-20210125]
[cannot apply to mac80211/master v5.11-rc5]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Felix-Fietkau/mac80211-minstrel_ht-use-bitfields-to-encode-rate-indexes/20210125-210635
base: https://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next.git master
config: x86_64-randconfig-a015-20210125 (attached as .config)
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 12d0753aca22896fda2cf76781b0ee0524d55065)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install x86_64 cross compiling tool for clang build
# apt-get install binutils-x86-64-linux-gnu
# https://github.com/0day-ci/linux/commit/8a2d01887013f71806262345f71766d6518e3552
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Felix-Fietkau/mac80211-minstrel_ht-use-bitfields-to-encode-rate-indexes/20210125-210635
git checkout 8a2d01887013f71806262345f71766d6518e3552
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
>> net/mac80211/rc80211_minstrel_ht.c:862:11: warning: variable 'group' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
else if (mi->supported[MINSTREL_OFDM_GROUP])
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
net/mac80211/rc80211_minstrel_ht.c:865:18: note: uninitialized use occurs here
index = MI_RATE(group, 0);
^~~~~
net/mac80211/rc80211_minstrel_ht.h:66:34: note: expanded from macro 'MI_RATE'
(FIELD_PREP(MI_RATE_GROUP_MASK, _group) | \
^~~~~~
include/linux/bitfield.h:95:20: note: expanded from macro 'FIELD_PREP'
((typeof(_mask))(_val) << __bf_shf(_mask)) & (_mask); \
^~~~
net/mac80211/rc80211_minstrel_ht.c:862:7: note: remove the 'if' if its condition is always true
else if (mi->supported[MINSTREL_OFDM_GROUP])
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
net/mac80211/rc80211_minstrel_ht.c:825:11: note: initialize the variable 'group' to silence this warning
int group, i, j, cur_prob;
^
= 0
1 warning generated.
vim +862 net/mac80211/rc80211_minstrel_ht.c
cbda98c710d273b Felix Fietkau 2021-01-15 809
ec8aa669b8393b6 Felix Fietkau 2010-05-13 810 /*
ec8aa669b8393b6 Felix Fietkau 2010-05-13 811 * Update rate statistics and select new primary rates
ec8aa669b8393b6 Felix Fietkau 2010-05-13 812 *
ec8aa669b8393b6 Felix Fietkau 2010-05-13 813 * Rules for rate selection:
ec8aa669b8393b6 Felix Fietkau 2010-05-13 814 * - max_prob_rate must use only one stream, as a tradeoff between delivery
ec8aa669b8393b6 Felix Fietkau 2010-05-13 815 * probability and throughput during strong fluctuations
5935839ad735837 Thomas Huehn 2014-09-09 816 * - as long as the max prob rate has a probability of more than 75%, pick
ec8aa669b8393b6 Felix Fietkau 2010-05-13 817 * higher throughput rates, even if the probablity is a bit lower
ec8aa669b8393b6 Felix Fietkau 2010-05-13 818 */
ec8aa669b8393b6 Felix Fietkau 2010-05-13 819 static void
48cb39522a9d4d4 Felix Fietkau 2019-08-20 820 minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
48cb39522a9d4d4 Felix Fietkau 2019-08-20 821 bool sample)
ec8aa669b8393b6 Felix Fietkau 2010-05-13 822 {
ec8aa669b8393b6 Felix Fietkau 2010-05-13 823 struct minstrel_mcs_group_data *mg;
9134073bc693633 Thomas Huehn 2015-03-24 824 struct minstrel_rate_stats *mrs;
50e55a8ea76fb59 Thomas Huehn 2015-03-24 825 int group, i, j, cur_prob;
d4d141cae804a43 Karl Beldan 2014-10-20 826 u16 tmp_mcs_tp_rate[MAX_THR_RATES], tmp_group_tp_rate[MAX_THR_RATES];
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 827 u16 tmp_legacy_tp_rate[MAX_THR_RATES], tmp_max_prob_rate;
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 828 u16 index;
a7844a53846017c Felix Fietkau 2021-01-15 829 bool ht_supported = mi->sta->ht_cap.ht_supported;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 830
48cb39522a9d4d4 Felix Fietkau 2019-08-20 831 mi->sample_mode = MINSTREL_SAMPLE_IDLE;
48cb39522a9d4d4 Felix Fietkau 2019-08-20 832
48cb39522a9d4d4 Felix Fietkau 2019-08-20 833 if (sample) {
48cb39522a9d4d4 Felix Fietkau 2019-08-20 834 mi->total_packets_cur = mi->total_packets -
48cb39522a9d4d4 Felix Fietkau 2019-08-20 835 mi->total_packets_last;
48cb39522a9d4d4 Felix Fietkau 2019-08-20 836 mi->total_packets_last = mi->total_packets;
48cb39522a9d4d4 Felix Fietkau 2019-08-20 837 }
48cb39522a9d4d4 Felix Fietkau 2019-08-20 838 if (!mp->sample_switch)
48cb39522a9d4d4 Felix Fietkau 2019-08-20 839 sample = false;
48cb39522a9d4d4 Felix Fietkau 2019-08-20 840 if (mi->total_packets_cur < SAMPLE_SWITCH_THR && mp->sample_switch != 1)
48cb39522a9d4d4 Felix Fietkau 2019-08-20 841 sample = false;
48cb39522a9d4d4 Felix Fietkau 2019-08-20 842
ec8aa669b8393b6 Felix Fietkau 2010-05-13 843 if (mi->ampdu_packets > 0) {
77f7ffdc335de85 Felix Fietkau 2019-01-16 844 if (!ieee80211_hw_check(mp->hw, TX_STATUS_NO_AMPDU_LEN))
ec8aa669b8393b6 Felix Fietkau 2010-05-13 845 mi->avg_ampdu_len = minstrel_ewma(mi->avg_ampdu_len,
77f7ffdc335de85 Felix Fietkau 2019-01-16 846 MINSTREL_FRAC(mi->ampdu_len, mi->ampdu_packets),
77f7ffdc335de85 Felix Fietkau 2019-01-16 847 EWMA_LEVEL);
77f7ffdc335de85 Felix Fietkau 2019-01-16 848 else
77f7ffdc335de85 Felix Fietkau 2019-01-16 849 mi->avg_ampdu_len = 0;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 850 mi->ampdu_len = 0;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 851 mi->ampdu_packets = 0;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 852 }
ec8aa669b8393b6 Felix Fietkau 2010-05-13 853
ec8aa669b8393b6 Felix Fietkau 2010-05-13 854 mi->sample_slow = 0;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 855 mi->sample_count = 0;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 856
21f7981b4bd9048 Felix Fietkau 2019-08-20 857 memset(tmp_mcs_tp_rate, 0, sizeof(tmp_mcs_tp_rate));
a7844a53846017c Felix Fietkau 2021-01-15 858 memset(tmp_legacy_tp_rate, 0, sizeof(tmp_legacy_tp_rate));
8a2d01887013f71 Felix Fietkau 2021-01-24 859
21f7981b4bd9048 Felix Fietkau 2019-08-20 860 if (mi->supported[MINSTREL_CCK_GROUP])
8a2d01887013f71 Felix Fietkau 2021-01-24 861 group = MINSTREL_CCK_GROUP;
a7844a53846017c Felix Fietkau 2021-01-15 @862 else if (mi->supported[MINSTREL_OFDM_GROUP])
8a2d01887013f71 Felix Fietkau 2021-01-24 863 group = MINSTREL_OFDM_GROUP;
8a2d01887013f71 Felix Fietkau 2021-01-24 864
8a2d01887013f71 Felix Fietkau 2021-01-24 865 index = MI_RATE(group, 0);
a7844a53846017c Felix Fietkau 2021-01-15 866 for (j = 0; j < ARRAY_SIZE(tmp_legacy_tp_rate); j++)
8a2d01887013f71 Felix Fietkau 2021-01-24 867 tmp_legacy_tp_rate[j] = index;
21f7981b4bd9048 Felix Fietkau 2019-08-20 868
21f7981b4bd9048 Felix Fietkau 2019-08-20 869 if (mi->supported[MINSTREL_VHT_GROUP_0])
8a2d01887013f71 Felix Fietkau 2021-01-24 870 group = MINSTREL_VHT_GROUP_0;
a7844a53846017c Felix Fietkau 2021-01-15 871 else if (ht_supported)
8a2d01887013f71 Felix Fietkau 2021-01-24 872 group = MINSTREL_HT_GROUP_0;
a7844a53846017c Felix Fietkau 2021-01-15 873 else if (mi->supported[MINSTREL_CCK_GROUP])
8a2d01887013f71 Felix Fietkau 2021-01-24 874 group = MINSTREL_CCK_GROUP;
a7844a53846017c Felix Fietkau 2021-01-15 875 else
8a2d01887013f71 Felix Fietkau 2021-01-24 876 group = MINSTREL_OFDM_GROUP;
21f7981b4bd9048 Felix Fietkau 2019-08-20 877
8a2d01887013f71 Felix Fietkau 2021-01-24 878 index = MI_RATE(group, 0);
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 879 tmp_max_prob_rate = index;
21f7981b4bd9048 Felix Fietkau 2019-08-20 880 for (j = 0; j < ARRAY_SIZE(tmp_mcs_tp_rate); j++)
21f7981b4bd9048 Felix Fietkau 2019-08-20 881 tmp_mcs_tp_rate[j] = index;
c2eb5b0f342c9b1 Karl Beldan 2013-04-18 882
5935839ad735837 Thomas Huehn 2014-09-09 883 /* Find best rate sets within all MCS groups*/
5935839ad735837 Thomas Huehn 2014-09-09 884 for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) {
a7844a53846017c Felix Fietkau 2021-01-15 885 u16 *tp_rate = tmp_mcs_tp_rate;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 886
ec8aa669b8393b6 Felix Fietkau 2010-05-13 887 mg = &mi->groups[group];
41d085835d3d225 Felix Fietkau 2016-12-14 888 if (!mi->supported[group])
ec8aa669b8393b6 Felix Fietkau 2010-05-13 889 continue;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 890
ec8aa669b8393b6 Felix Fietkau 2010-05-13 891 mi->sample_count++;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 892
5935839ad735837 Thomas Huehn 2014-09-09 893 /* (re)Initialize group rate indexes */
5935839ad735837 Thomas Huehn 2014-09-09 894 for(j = 0; j < MAX_THR_RATES; j++)
8a2d01887013f71 Felix Fietkau 2021-01-24 895 tmp_group_tp_rate[j] = MI_RATE(group, 0);
5935839ad735837 Thomas Huehn 2014-09-09 896
a7844a53846017c Felix Fietkau 2021-01-15 897 if (group == MINSTREL_CCK_GROUP && ht_supported)
a7844a53846017c Felix Fietkau 2021-01-15 898 tp_rate = tmp_legacy_tp_rate;
a7844a53846017c Felix Fietkau 2021-01-15 899
ec8aa669b8393b6 Felix Fietkau 2010-05-13 900 for (i = 0; i < MCS_GROUP_RATES; i++) {
41d085835d3d225 Felix Fietkau 2016-12-14 901 if (!(mi->supported[group] & BIT(i)))
ec8aa669b8393b6 Felix Fietkau 2010-05-13 902 continue;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 903
8a2d01887013f71 Felix Fietkau 2021-01-24 904 index = MI_RATE(group, i);
351df099721e02e Karl Beldan 2013-11-13 905
9134073bc693633 Thomas Huehn 2015-03-24 906 mrs = &mg->rates[i];
9134073bc693633 Thomas Huehn 2015-03-24 907 mrs->retry_updated = false;
cbda98c710d273b Felix Fietkau 2021-01-15 908 minstrel_ht_calc_rate_stats(mp, mrs);
5f63afe0288d955 Felix Fietkau 2019-10-08 909 cur_prob = mrs->prob_avg;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 910
50e55a8ea76fb59 Thomas Huehn 2015-03-24 911 if (minstrel_ht_get_tp_avg(mi, group, i, cur_prob) == 0)
ec8aa669b8393b6 Felix Fietkau 2010-05-13 912 continue;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 913
5935839ad735837 Thomas Huehn 2014-09-09 914 /* Find max throughput rate set */
a7844a53846017c Felix Fietkau 2021-01-15 915 minstrel_ht_sort_best_tp_rates(mi, index, tp_rate);
ec8aa669b8393b6 Felix Fietkau 2010-05-13 916
5935839ad735837 Thomas Huehn 2014-09-09 917 /* Find max throughput rate set within a group */
5935839ad735837 Thomas Huehn 2014-09-09 918 minstrel_ht_sort_best_tp_rates(mi, index,
5935839ad735837 Thomas Huehn 2014-09-09 919 tmp_group_tp_rate);
ec8aa669b8393b6 Felix Fietkau 2010-05-13 920 }
ec8aa669b8393b6 Felix Fietkau 2010-05-13 921
5935839ad735837 Thomas Huehn 2014-09-09 922 memcpy(mg->max_group_tp_rate, tmp_group_tp_rate,
5935839ad735837 Thomas Huehn 2014-09-09 923 sizeof(mg->max_group_tp_rate));
ec8aa669b8393b6 Felix Fietkau 2010-05-13 924 }
ec8aa669b8393b6 Felix Fietkau 2010-05-13 925
5935839ad735837 Thomas Huehn 2014-09-09 926 /* Assign new rate set per sta */
a7844a53846017c Felix Fietkau 2021-01-15 927 minstrel_ht_assign_best_tp_rates(mi, tmp_mcs_tp_rate,
a7844a53846017c Felix Fietkau 2021-01-15 928 tmp_legacy_tp_rate);
5935839ad735837 Thomas Huehn 2014-09-09 929 memcpy(mi->max_tp_rate, tmp_mcs_tp_rate, sizeof(mi->max_tp_rate));
ec8aa669b8393b6 Felix Fietkau 2010-05-13 930
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 931 for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) {
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 932 if (!mi->supported[group])
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 933 continue;
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 934
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 935 mg = &mi->groups[group];
8a2d01887013f71 Felix Fietkau 2021-01-24 936 mg->max_group_prob_rate = MI_RATE(group, 0);
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 937
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 938 for (i = 0; i < MCS_GROUP_RATES; i++) {
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 939 if (!(mi->supported[group] & BIT(i)))
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 940 continue;
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 941
8a2d01887013f71 Felix Fietkau 2021-01-24 942 index = MI_RATE(group, i);
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 943
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 944 /* Find max probability rate per group and global */
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 945 minstrel_ht_set_best_prob_rate(mi, &tmp_max_prob_rate,
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 946 index);
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 947 }
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 948 }
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 949
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 950 mi->max_prob_rate = tmp_max_prob_rate;
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 951
5935839ad735837 Thomas Huehn 2014-09-09 952 /* Try to increase robustness of max_prob_rate*/
5935839ad735837 Thomas Huehn 2014-09-09 953 minstrel_ht_prob_rate_reduce_streams(mi);
a299c6d591f8f6a Felix Fietkau 2013-03-02 954
eeafcb0c80c81d6 Felix Fietkau 2021-01-15 955 /* try to sample half of all available rates during each interval */
eeafcb0c80c81d6 Felix Fietkau 2021-01-15 956 mi->sample_count *= 4;
a299c6d591f8f6a Felix Fietkau 2013-03-02 957
48cb39522a9d4d4 Felix Fietkau 2019-08-20 958 if (sample)
48cb39522a9d4d4 Felix Fietkau 2019-08-20 959 minstrel_ht_rate_sample_switch(mp, mi);
48cb39522a9d4d4 Felix Fietkau 2019-08-20 960
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 35873 bytes --]
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH 1/6] mac80211: minstrel_ht: use bitfields to encode rate indexes
@ 2021-01-25 19:25 ` kernel test robot
0 siblings, 0 replies; 12+ messages in thread
From: kernel test robot @ 2021-01-25 19:25 UTC (permalink / raw)
To: kbuild-all
[-- Attachment #1: Type: text/plain, Size: 14710 bytes --]
Hi Felix,
I love your patch! Perhaps something to improve:
[auto build test WARNING on mac80211-next/master]
[also build test WARNING on next-20210125]
[cannot apply to mac80211/master v5.11-rc5]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Felix-Fietkau/mac80211-minstrel_ht-use-bitfields-to-encode-rate-indexes/20210125-210635
base: https://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next.git master
config: x86_64-randconfig-a015-20210125 (attached as .config)
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 12d0753aca22896fda2cf76781b0ee0524d55065)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install x86_64 cross compiling tool for clang build
# apt-get install binutils-x86-64-linux-gnu
# https://github.com/0day-ci/linux/commit/8a2d01887013f71806262345f71766d6518e3552
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Felix-Fietkau/mac80211-minstrel_ht-use-bitfields-to-encode-rate-indexes/20210125-210635
git checkout 8a2d01887013f71806262345f71766d6518e3552
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
>> net/mac80211/rc80211_minstrel_ht.c:862:11: warning: variable 'group' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
else if (mi->supported[MINSTREL_OFDM_GROUP])
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
net/mac80211/rc80211_minstrel_ht.c:865:18: note: uninitialized use occurs here
index = MI_RATE(group, 0);
^~~~~
net/mac80211/rc80211_minstrel_ht.h:66:34: note: expanded from macro 'MI_RATE'
(FIELD_PREP(MI_RATE_GROUP_MASK, _group) | \
^~~~~~
include/linux/bitfield.h:95:20: note: expanded from macro 'FIELD_PREP'
((typeof(_mask))(_val) << __bf_shf(_mask)) & (_mask); \
^~~~
net/mac80211/rc80211_minstrel_ht.c:862:7: note: remove the 'if' if its condition is always true
else if (mi->supported[MINSTREL_OFDM_GROUP])
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
net/mac80211/rc80211_minstrel_ht.c:825:11: note: initialize the variable 'group' to silence this warning
int group, i, j, cur_prob;
^
= 0
1 warning generated.
vim +862 net/mac80211/rc80211_minstrel_ht.c
cbda98c710d273b Felix Fietkau 2021-01-15 809
ec8aa669b8393b6 Felix Fietkau 2010-05-13 810 /*
ec8aa669b8393b6 Felix Fietkau 2010-05-13 811 * Update rate statistics and select new primary rates
ec8aa669b8393b6 Felix Fietkau 2010-05-13 812 *
ec8aa669b8393b6 Felix Fietkau 2010-05-13 813 * Rules for rate selection:
ec8aa669b8393b6 Felix Fietkau 2010-05-13 814 * - max_prob_rate must use only one stream, as a tradeoff between delivery
ec8aa669b8393b6 Felix Fietkau 2010-05-13 815 * probability and throughput during strong fluctuations
5935839ad735837 Thomas Huehn 2014-09-09 816 * - as long as the max prob rate has a probability of more than 75%, pick
ec8aa669b8393b6 Felix Fietkau 2010-05-13 817 * higher throughput rates, even if the probablity is a bit lower
ec8aa669b8393b6 Felix Fietkau 2010-05-13 818 */
ec8aa669b8393b6 Felix Fietkau 2010-05-13 819 static void
48cb39522a9d4d4 Felix Fietkau 2019-08-20 820 minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
48cb39522a9d4d4 Felix Fietkau 2019-08-20 821 bool sample)
ec8aa669b8393b6 Felix Fietkau 2010-05-13 822 {
ec8aa669b8393b6 Felix Fietkau 2010-05-13 823 struct minstrel_mcs_group_data *mg;
9134073bc693633 Thomas Huehn 2015-03-24 824 struct minstrel_rate_stats *mrs;
50e55a8ea76fb59 Thomas Huehn 2015-03-24 825 int group, i, j, cur_prob;
d4d141cae804a43 Karl Beldan 2014-10-20 826 u16 tmp_mcs_tp_rate[MAX_THR_RATES], tmp_group_tp_rate[MAX_THR_RATES];
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 827 u16 tmp_legacy_tp_rate[MAX_THR_RATES], tmp_max_prob_rate;
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 828 u16 index;
a7844a53846017c Felix Fietkau 2021-01-15 829 bool ht_supported = mi->sta->ht_cap.ht_supported;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 830
48cb39522a9d4d4 Felix Fietkau 2019-08-20 831 mi->sample_mode = MINSTREL_SAMPLE_IDLE;
48cb39522a9d4d4 Felix Fietkau 2019-08-20 832
48cb39522a9d4d4 Felix Fietkau 2019-08-20 833 if (sample) {
48cb39522a9d4d4 Felix Fietkau 2019-08-20 834 mi->total_packets_cur = mi->total_packets -
48cb39522a9d4d4 Felix Fietkau 2019-08-20 835 mi->total_packets_last;
48cb39522a9d4d4 Felix Fietkau 2019-08-20 836 mi->total_packets_last = mi->total_packets;
48cb39522a9d4d4 Felix Fietkau 2019-08-20 837 }
48cb39522a9d4d4 Felix Fietkau 2019-08-20 838 if (!mp->sample_switch)
48cb39522a9d4d4 Felix Fietkau 2019-08-20 839 sample = false;
48cb39522a9d4d4 Felix Fietkau 2019-08-20 840 if (mi->total_packets_cur < SAMPLE_SWITCH_THR && mp->sample_switch != 1)
48cb39522a9d4d4 Felix Fietkau 2019-08-20 841 sample = false;
48cb39522a9d4d4 Felix Fietkau 2019-08-20 842
ec8aa669b8393b6 Felix Fietkau 2010-05-13 843 if (mi->ampdu_packets > 0) {
77f7ffdc335de85 Felix Fietkau 2019-01-16 844 if (!ieee80211_hw_check(mp->hw, TX_STATUS_NO_AMPDU_LEN))
ec8aa669b8393b6 Felix Fietkau 2010-05-13 845 mi->avg_ampdu_len = minstrel_ewma(mi->avg_ampdu_len,
77f7ffdc335de85 Felix Fietkau 2019-01-16 846 MINSTREL_FRAC(mi->ampdu_len, mi->ampdu_packets),
77f7ffdc335de85 Felix Fietkau 2019-01-16 847 EWMA_LEVEL);
77f7ffdc335de85 Felix Fietkau 2019-01-16 848 else
77f7ffdc335de85 Felix Fietkau 2019-01-16 849 mi->avg_ampdu_len = 0;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 850 mi->ampdu_len = 0;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 851 mi->ampdu_packets = 0;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 852 }
ec8aa669b8393b6 Felix Fietkau 2010-05-13 853
ec8aa669b8393b6 Felix Fietkau 2010-05-13 854 mi->sample_slow = 0;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 855 mi->sample_count = 0;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 856
21f7981b4bd9048 Felix Fietkau 2019-08-20 857 memset(tmp_mcs_tp_rate, 0, sizeof(tmp_mcs_tp_rate));
a7844a53846017c Felix Fietkau 2021-01-15 858 memset(tmp_legacy_tp_rate, 0, sizeof(tmp_legacy_tp_rate));
8a2d01887013f71 Felix Fietkau 2021-01-24 859
21f7981b4bd9048 Felix Fietkau 2019-08-20 860 if (mi->supported[MINSTREL_CCK_GROUP])
8a2d01887013f71 Felix Fietkau 2021-01-24 861 group = MINSTREL_CCK_GROUP;
a7844a53846017c Felix Fietkau 2021-01-15 @862 else if (mi->supported[MINSTREL_OFDM_GROUP])
8a2d01887013f71 Felix Fietkau 2021-01-24 863 group = MINSTREL_OFDM_GROUP;
8a2d01887013f71 Felix Fietkau 2021-01-24 864
8a2d01887013f71 Felix Fietkau 2021-01-24 865 index = MI_RATE(group, 0);
a7844a53846017c Felix Fietkau 2021-01-15 866 for (j = 0; j < ARRAY_SIZE(tmp_legacy_tp_rate); j++)
8a2d01887013f71 Felix Fietkau 2021-01-24 867 tmp_legacy_tp_rate[j] = index;
21f7981b4bd9048 Felix Fietkau 2019-08-20 868
21f7981b4bd9048 Felix Fietkau 2019-08-20 869 if (mi->supported[MINSTREL_VHT_GROUP_0])
8a2d01887013f71 Felix Fietkau 2021-01-24 870 group = MINSTREL_VHT_GROUP_0;
a7844a53846017c Felix Fietkau 2021-01-15 871 else if (ht_supported)
8a2d01887013f71 Felix Fietkau 2021-01-24 872 group = MINSTREL_HT_GROUP_0;
a7844a53846017c Felix Fietkau 2021-01-15 873 else if (mi->supported[MINSTREL_CCK_GROUP])
8a2d01887013f71 Felix Fietkau 2021-01-24 874 group = MINSTREL_CCK_GROUP;
a7844a53846017c Felix Fietkau 2021-01-15 875 else
8a2d01887013f71 Felix Fietkau 2021-01-24 876 group = MINSTREL_OFDM_GROUP;
21f7981b4bd9048 Felix Fietkau 2019-08-20 877
8a2d01887013f71 Felix Fietkau 2021-01-24 878 index = MI_RATE(group, 0);
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 879 tmp_max_prob_rate = index;
21f7981b4bd9048 Felix Fietkau 2019-08-20 880 for (j = 0; j < ARRAY_SIZE(tmp_mcs_tp_rate); j++)
21f7981b4bd9048 Felix Fietkau 2019-08-20 881 tmp_mcs_tp_rate[j] = index;
c2eb5b0f342c9b1 Karl Beldan 2013-04-18 882
5935839ad735837 Thomas Huehn 2014-09-09 883 /* Find best rate sets within all MCS groups*/
5935839ad735837 Thomas Huehn 2014-09-09 884 for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) {
a7844a53846017c Felix Fietkau 2021-01-15 885 u16 *tp_rate = tmp_mcs_tp_rate;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 886
ec8aa669b8393b6 Felix Fietkau 2010-05-13 887 mg = &mi->groups[group];
41d085835d3d225 Felix Fietkau 2016-12-14 888 if (!mi->supported[group])
ec8aa669b8393b6 Felix Fietkau 2010-05-13 889 continue;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 890
ec8aa669b8393b6 Felix Fietkau 2010-05-13 891 mi->sample_count++;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 892
5935839ad735837 Thomas Huehn 2014-09-09 893 /* (re)Initialize group rate indexes */
5935839ad735837 Thomas Huehn 2014-09-09 894 for(j = 0; j < MAX_THR_RATES; j++)
8a2d01887013f71 Felix Fietkau 2021-01-24 895 tmp_group_tp_rate[j] = MI_RATE(group, 0);
5935839ad735837 Thomas Huehn 2014-09-09 896
a7844a53846017c Felix Fietkau 2021-01-15 897 if (group == MINSTREL_CCK_GROUP && ht_supported)
a7844a53846017c Felix Fietkau 2021-01-15 898 tp_rate = tmp_legacy_tp_rate;
a7844a53846017c Felix Fietkau 2021-01-15 899
ec8aa669b8393b6 Felix Fietkau 2010-05-13 900 for (i = 0; i < MCS_GROUP_RATES; i++) {
41d085835d3d225 Felix Fietkau 2016-12-14 901 if (!(mi->supported[group] & BIT(i)))
ec8aa669b8393b6 Felix Fietkau 2010-05-13 902 continue;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 903
8a2d01887013f71 Felix Fietkau 2021-01-24 904 index = MI_RATE(group, i);
351df099721e02e Karl Beldan 2013-11-13 905
9134073bc693633 Thomas Huehn 2015-03-24 906 mrs = &mg->rates[i];
9134073bc693633 Thomas Huehn 2015-03-24 907 mrs->retry_updated = false;
cbda98c710d273b Felix Fietkau 2021-01-15 908 minstrel_ht_calc_rate_stats(mp, mrs);
5f63afe0288d955 Felix Fietkau 2019-10-08 909 cur_prob = mrs->prob_avg;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 910
50e55a8ea76fb59 Thomas Huehn 2015-03-24 911 if (minstrel_ht_get_tp_avg(mi, group, i, cur_prob) == 0)
ec8aa669b8393b6 Felix Fietkau 2010-05-13 912 continue;
ec8aa669b8393b6 Felix Fietkau 2010-05-13 913
5935839ad735837 Thomas Huehn 2014-09-09 914 /* Find max throughput rate set */
a7844a53846017c Felix Fietkau 2021-01-15 915 minstrel_ht_sort_best_tp_rates(mi, index, tp_rate);
ec8aa669b8393b6 Felix Fietkau 2010-05-13 916
5935839ad735837 Thomas Huehn 2014-09-09 917 /* Find max throughput rate set within a group */
5935839ad735837 Thomas Huehn 2014-09-09 918 minstrel_ht_sort_best_tp_rates(mi, index,
5935839ad735837 Thomas Huehn 2014-09-09 919 tmp_group_tp_rate);
ec8aa669b8393b6 Felix Fietkau 2010-05-13 920 }
ec8aa669b8393b6 Felix Fietkau 2010-05-13 921
5935839ad735837 Thomas Huehn 2014-09-09 922 memcpy(mg->max_group_tp_rate, tmp_group_tp_rate,
5935839ad735837 Thomas Huehn 2014-09-09 923 sizeof(mg->max_group_tp_rate));
ec8aa669b8393b6 Felix Fietkau 2010-05-13 924 }
ec8aa669b8393b6 Felix Fietkau 2010-05-13 925
5935839ad735837 Thomas Huehn 2014-09-09 926 /* Assign new rate set per sta */
a7844a53846017c Felix Fietkau 2021-01-15 927 minstrel_ht_assign_best_tp_rates(mi, tmp_mcs_tp_rate,
a7844a53846017c Felix Fietkau 2021-01-15 928 tmp_legacy_tp_rate);
5935839ad735837 Thomas Huehn 2014-09-09 929 memcpy(mi->max_tp_rate, tmp_mcs_tp_rate, sizeof(mi->max_tp_rate));
ec8aa669b8393b6 Felix Fietkau 2010-05-13 930
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 931 for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) {
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 932 if (!mi->supported[group])
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 933 continue;
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 934
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 935 mg = &mi->groups[group];
8a2d01887013f71 Felix Fietkau 2021-01-24 936 mg->max_group_prob_rate = MI_RATE(group, 0);
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 937
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 938 for (i = 0; i < MCS_GROUP_RATES; i++) {
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 939 if (!(mi->supported[group] & BIT(i)))
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 940 continue;
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 941
8a2d01887013f71 Felix Fietkau 2021-01-24 942 index = MI_RATE(group, i);
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 943
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 944 /* Find max probability rate per group and global */
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 945 minstrel_ht_set_best_prob_rate(mi, &tmp_max_prob_rate,
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 946 index);
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 947 }
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 948 }
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 949
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 950 mi->max_prob_rate = tmp_max_prob_rate;
a7fca4e4037f7e3 Felix Fietkau 2021-01-15 951
5935839ad735837 Thomas Huehn 2014-09-09 952 /* Try to increase robustness of max_prob_rate*/
5935839ad735837 Thomas Huehn 2014-09-09 953 minstrel_ht_prob_rate_reduce_streams(mi);
a299c6d591f8f6a Felix Fietkau 2013-03-02 954
eeafcb0c80c81d6 Felix Fietkau 2021-01-15 955 /* try to sample half of all available rates during each interval */
eeafcb0c80c81d6 Felix Fietkau 2021-01-15 956 mi->sample_count *= 4;
a299c6d591f8f6a Felix Fietkau 2013-03-02 957
48cb39522a9d4d4 Felix Fietkau 2019-08-20 958 if (sample)
48cb39522a9d4d4 Felix Fietkau 2019-08-20 959 minstrel_ht_rate_sample_switch(mp, mi);
48cb39522a9d4d4 Felix Fietkau 2019-08-20 960
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org
[-- Attachment #2: config.gz --]
[-- Type: application/gzip, Size: 35873 bytes --]
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH 4/6] mac80211: minstrel_ht: significantly redesign the rate probing strategy
2021-01-25 11:56 ` Toke Høiland-Jørgensen
@ 2021-01-25 20:46 ` Felix Fietkau
2021-01-25 21:21 ` Toke Høiland-Jørgensen
0 siblings, 1 reply; 12+ messages in thread
From: Felix Fietkau @ 2021-01-25 20:46 UTC (permalink / raw)
To: Toke Høiland-Jørgensen, linux-wireless; +Cc: johannes
On 2021-01-25 12:56, Toke Høiland-Jørgensen wrote:
> Felix Fietkau <nbd@nbd.name> writes:
>
>> The biggest flaw in current minstrel_ht is the fact that it needs way too
>> many probing packets to be able to quickly find the best rate.
>> Depending on the wifi hardware and operating mode, this can significantly
>> reduce throughput when not operating at the highest available data rate.
>>
>> In order to be able to significantly reduce the amount of rate sampling,
>> we need a much smarter selection of probing rates.
>>
>> The new approach introduced by this patch maintains a limited set of
>> available rates to be tested during a statistics window.
>>
>> They are split into distinct categories:
>> - MINSTREL_SAMPLE_TYPE_INC - incremental rate upgrade:
>> Pick the next rate group and find the first rate that is faster than
>> the current max. throughput rate
>> - MINSTREL_SAMPLE_TYPE_JUMP - random testing of higher rates:
>> Pick a random rate from the next group that is faster than the current
>> max throughput rate. This allows faster adaptation when the link changes
>> significantly
>> - MINSTREL_SAMPLE_TYPE_SLOW - test a rate between max_prob, max_tp2 and
>> max_tp in order to reduce the gap between them
>>
>> In order to prioritize sampling, every 6 attempts are split into 3x INC,
>> 2x JUMP, 1x SLOW.
>>
>> Available rates are checked and refilled on every stats window update.
>
> Very cool!
>
>> With this approach, we finally get a very small delta in throughput when
>> comparing setting the optimal data rate as a fixed rate vs normal rate
>> control operation.
>
> Can you quantify this "very small delta"? Would love to see some
> benchmark data :)
Based on a quick test it seems to be around 5% (sometimes less) at VHT80
MCS6 nss=4 with ~350 mbit/s TCP throughput. I guess I might be able to
bring that down even further, once I optimize it some more.
- Felix
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH 4/6] mac80211: minstrel_ht: significantly redesign the rate probing strategy
2021-01-25 20:46 ` Felix Fietkau
@ 2021-01-25 21:21 ` Toke Høiland-Jørgensen
2021-01-25 21:27 ` Felix Fietkau
0 siblings, 1 reply; 12+ messages in thread
From: Toke Høiland-Jørgensen @ 2021-01-25 21:21 UTC (permalink / raw)
To: Felix Fietkau, linux-wireless; +Cc: johannes
Felix Fietkau <nbd@nbd.name> writes:
> On 2021-01-25 12:56, Toke Høiland-Jørgensen wrote:
>> Felix Fietkau <nbd@nbd.name> writes:
>>
>>> The biggest flaw in current minstrel_ht is the fact that it needs way too
>>> many probing packets to be able to quickly find the best rate.
>>> Depending on the wifi hardware and operating mode, this can significantly
>>> reduce throughput when not operating at the highest available data rate.
>>>
>>> In order to be able to significantly reduce the amount of rate sampling,
>>> we need a much smarter selection of probing rates.
>>>
>>> The new approach introduced by this patch maintains a limited set of
>>> available rates to be tested during a statistics window.
>>>
>>> They are split into distinct categories:
>>> - MINSTREL_SAMPLE_TYPE_INC - incremental rate upgrade:
>>> Pick the next rate group and find the first rate that is faster than
>>> the current max. throughput rate
>>> - MINSTREL_SAMPLE_TYPE_JUMP - random testing of higher rates:
>>> Pick a random rate from the next group that is faster than the current
>>> max throughput rate. This allows faster adaptation when the link changes
>>> significantly
>>> - MINSTREL_SAMPLE_TYPE_SLOW - test a rate between max_prob, max_tp2 and
>>> max_tp in order to reduce the gap between them
>>>
>>> In order to prioritize sampling, every 6 attempts are split into 3x INC,
>>> 2x JUMP, 1x SLOW.
>>>
>>> Available rates are checked and refilled on every stats window update.
>>
>> Very cool!
>>
>>> With this approach, we finally get a very small delta in throughput when
>>> comparing setting the optimal data rate as a fixed rate vs normal rate
>>> control operation.
>>
>> Can you quantify this "very small delta"? Would love to see some
>> benchmark data :)
> Based on a quick test it seems to be around 5% (sometimes less) at VHT80
> MCS6 nss=4 with ~350 mbit/s TCP throughput. I guess I might be able to
> bring that down even further, once I optimize it some more.
Cool! And pre-patch?
-Toke
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH 4/6] mac80211: minstrel_ht: significantly redesign the rate probing strategy
2021-01-25 21:21 ` Toke Høiland-Jørgensen
@ 2021-01-25 21:27 ` Felix Fietkau
0 siblings, 0 replies; 12+ messages in thread
From: Felix Fietkau @ 2021-01-25 21:27 UTC (permalink / raw)
To: Toke Høiland-Jørgensen, linux-wireless; +Cc: johannes
On 2021-01-25 22:21, Toke Høiland-Jørgensen wrote:
> Felix Fietkau <nbd@nbd.name> writes:
>
>> On 2021-01-25 12:56, Toke Høiland-Jørgensen wrote:
>>> Felix Fietkau <nbd@nbd.name> writes:
>>>> With this approach, we finally get a very small delta in throughput when
>>>> comparing setting the optimal data rate as a fixed rate vs normal rate
>>>> control operation.
>>>
>>> Can you quantify this "very small delta"? Would love to see some
>>> benchmark data :)
>> Based on a quick test it seems to be around 5% (sometimes less) at VHT80
>> MCS6 nss=4 with ~350 mbit/s TCP throughput. I guess I might be able to
>> bring that down even further, once I optimize it some more.
>
> Cool! And pre-patch?
Some users reported more than 30%
- Felix
^ permalink raw reply [flat|nested] 12+ messages in thread
end of thread, other threads:[~2021-01-26 5:57 UTC | newest]
Thread overview: 12+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-01-24 12:28 [PATCH 1/6] mac80211: minstrel_ht: use bitfields to encode rate indexes Felix Fietkau
2021-01-24 12:28 ` [PATCH 2/6] mac80211: minstrel_ht: update total packets counter in tx status path Felix Fietkau
2021-01-24 12:28 ` [PATCH 3/6] mac80211: minstrel_ht: reduce the need to sample slower rates Felix Fietkau
2021-01-24 12:28 ` [PATCH 4/6] mac80211: minstrel_ht: significantly redesign the rate probing strategy Felix Fietkau
2021-01-25 11:56 ` Toke Høiland-Jørgensen
2021-01-25 20:46 ` Felix Fietkau
2021-01-25 21:21 ` Toke Høiland-Jørgensen
2021-01-25 21:27 ` Felix Fietkau
2021-01-24 12:28 ` [PATCH 5/6] mac80211: minstrel_ht: show sampling rates in debugfs Felix Fietkau
2021-01-24 12:28 ` [PATCH 6/6] mac80211: minstrel_ht: remove sample rate switching code for constrained devices Felix Fietkau
2021-01-25 19:25 ` [PATCH 1/6] mac80211: minstrel_ht: use bitfields to encode rate indexes kernel test robot
2021-01-25 19:25 ` kernel test robot
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.