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Diffstat (limited to 'net/mac80211/rc80211_minstrel_ht.c')
-rw-r--r--net/mac80211/rc80211_minstrel_ht.c273
1 files changed, 159 insertions, 114 deletions
diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c
index 3af141c69712..5b2d3012b983 100644
--- a/net/mac80211/rc80211_minstrel_ht.c
+++ b/net/mac80211/rc80211_minstrel_ht.c
@@ -17,8 +17,6 @@
#include "rc80211_minstrel_ht.h"
#define AVG_PKT_SIZE 1200
-#define SAMPLE_COLUMNS 10
-#define EWMA_LEVEL 75
/* Number of bits for an average sized packet */
#define MCS_NBITS (AVG_PKT_SIZE << 3)
@@ -26,11 +24,11 @@
/* Number of symbols for a packet with (bps) bits per symbol */
#define MCS_NSYMS(bps) ((MCS_NBITS + (bps) - 1) / (bps))
-/* Transmission time for a packet containing (syms) symbols */
+/* Transmission time (nanoseconds) for a packet containing (syms) symbols */
#define MCS_SYMBOL_TIME(sgi, syms) \
(sgi ? \
- ((syms) * 18 + 4) / 5 : /* syms * 3.6 us */ \
- (syms) << 2 /* syms * 4 us */ \
+ ((syms) * 18000 + 4000) / 5 : /* syms * 3.6 us */ \
+ ((syms) * 1000) << 2 /* syms * 4 us */ \
)
/* Transmit duration for the raw data part of an average sized packet */
@@ -64,9 +62,9 @@
}
#define CCK_DURATION(_bitrate, _short, _len) \
- (10 /* SIFS */ + \
+ (1000 * (10 /* SIFS */ + \
(_short ? 72 + 24 : 144 + 48 ) + \
- (8 * (_len + 4) * 10) / (_bitrate))
+ (8 * (_len + 4) * 10) / (_bitrate)))
#define CCK_ACK_DURATION(_bitrate, _short) \
(CCK_DURATION((_bitrate > 10 ? 20 : 10), false, 60) + \
@@ -128,14 +126,8 @@ const struct mcs_group minstrel_mcs_groups[] = {
static u8 sample_table[SAMPLE_COLUMNS][MCS_GROUP_RATES];
-/*
- * Perform EWMA (Exponentially Weighted Moving Average) calculation
- */
-static int
-minstrel_ewma(int old, int new, int weight)
-{
- return (new * (100 - weight) + old * weight) / 100;
-}
+static void
+minstrel_ht_update_rates(struct minstrel_priv *mp, struct minstrel_ht_sta *mi);
/*
* Look up an MCS group index based on mac80211 rate information
@@ -211,20 +203,32 @@ static void
minstrel_ht_calc_tp(struct minstrel_ht_sta *mi, int group, int rate)
{
struct minstrel_rate_stats *mr;
- unsigned int usecs = 0;
+ unsigned int nsecs = 0;
+ unsigned int tp;
+ unsigned int prob;
mr = &mi->groups[group].rates[rate];
+ prob = mr->probability;
- if (mr->probability < MINSTREL_FRAC(1, 10)) {
+ if (prob < MINSTREL_FRAC(1, 10)) {
mr->cur_tp = 0;
return;
}
+ /*
+ * For the throughput calculation, limit the probability value to 90% to
+ * account for collision related packet error rate fluctuation
+ */
+ if (prob > MINSTREL_FRAC(9, 10))
+ prob = MINSTREL_FRAC(9, 10);
+
if (group != MINSTREL_CCK_GROUP)
- usecs = mi->overhead / MINSTREL_TRUNC(mi->avg_ampdu_len);
+ nsecs = 1000 * mi->overhead / MINSTREL_TRUNC(mi->avg_ampdu_len);
- usecs += minstrel_mcs_groups[group].duration[rate];
- mr->cur_tp = MINSTREL_TRUNC((1000000 / usecs) * mr->probability);
+ nsecs += minstrel_mcs_groups[group].duration[rate];
+ tp = 1000000 * ((mr->probability * 1000) / nsecs);
+
+ mr->cur_tp = MINSTREL_TRUNC(tp);
}
/*
@@ -243,6 +247,7 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
struct minstrel_rate_stats *mr;
int cur_prob, cur_prob_tp, cur_tp, cur_tp2;
int group, i, index;
+ bool mi_rates_valid = false;
if (mi->ampdu_packets > 0) {
mi->avg_ampdu_len = minstrel_ewma(mi->avg_ampdu_len,
@@ -253,11 +258,10 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
mi->sample_slow = 0;
mi->sample_count = 0;
- mi->max_tp_rate = 0;
- mi->max_tp_rate2 = 0;
- mi->max_prob_rate = 0;
for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) {
+ bool mg_rates_valid = false;
+
cur_prob = 0;
cur_prob_tp = 0;
cur_tp = 0;
@@ -267,15 +271,24 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
if (!mg->supported)
continue;
- mg->max_tp_rate = 0;
- mg->max_tp_rate2 = 0;
- mg->max_prob_rate = 0;
mi->sample_count++;
for (i = 0; i < MCS_GROUP_RATES; i++) {
if (!(mg->supported & BIT(i)))
continue;
+ /* initialize rates selections starting indexes */
+ if (!mg_rates_valid) {
+ mg->max_tp_rate = mg->max_tp_rate2 =
+ mg->max_prob_rate = i;
+ if (!mi_rates_valid) {
+ mi->max_tp_rate = mi->max_tp_rate2 =
+ mi->max_prob_rate = i;
+ mi_rates_valid = true;
+ }
+ mg_rates_valid = true;
+ }
+
mr = &mg->rates[i];
mr->retry_updated = false;
index = MCS_GROUP_RATES * group + i;
@@ -308,8 +321,8 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
}
}
- /* try to sample up to half of the available rates during each interval */
- mi->sample_count *= 4;
+ /* try to sample all available rates during each interval */
+ mi->sample_count *= 8;
cur_prob = 0;
cur_prob_tp = 0;
@@ -320,20 +333,13 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
if (!mg->supported)
continue;
- mr = minstrel_get_ratestats(mi, mg->max_prob_rate);
- if (cur_prob_tp < mr->cur_tp &&
- minstrel_mcs_groups[group].streams == 1) {
- mi->max_prob_rate = mg->max_prob_rate;
- cur_prob = mr->cur_prob;
- cur_prob_tp = mr->cur_tp;
- }
-
mr = minstrel_get_ratestats(mi, mg->max_tp_rate);
if (cur_tp < mr->cur_tp) {
mi->max_tp_rate2 = mi->max_tp_rate;
cur_tp2 = cur_tp;
mi->max_tp_rate = mg->max_tp_rate;
cur_tp = mr->cur_tp;
+ mi->max_prob_streams = minstrel_mcs_groups[group].streams - 1;
}
mr = minstrel_get_ratestats(mi, mg->max_tp_rate2);
@@ -343,6 +349,23 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
}
}
+ if (mi->max_prob_streams < 1)
+ mi->max_prob_streams = 1;
+
+ for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) {
+ mg = &mi->groups[group];
+ if (!mg->supported)
+ continue;
+ mr = minstrel_get_ratestats(mi, mg->max_prob_rate);
+ if (cur_prob_tp < mr->cur_tp &&
+ minstrel_mcs_groups[group].streams <= mi->max_prob_streams) {
+ mi->max_prob_rate = mg->max_prob_rate;
+ cur_prob = mr->cur_prob;
+ cur_prob_tp = mr->cur_tp;
+ }
+ }
+
+
mi->stats_update = jiffies;
}
@@ -445,7 +468,7 @@ minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband,
struct ieee80211_tx_rate *ar = info->status.rates;
struct minstrel_rate_stats *rate, *rate2;
struct minstrel_priv *mp = priv;
- bool last;
+ bool last, update = false;
int i;
if (!msp->is_ht)
@@ -467,7 +490,7 @@ minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband,
if (!mi->sample_wait && !mi->sample_tries && mi->sample_count > 0) {
mi->sample_wait = 16 + 2 * MINSTREL_TRUNC(mi->avg_ampdu_len);
- mi->sample_tries = 2;
+ mi->sample_tries = 1;
mi->sample_count--;
}
@@ -494,21 +517,29 @@ minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband,
rate = minstrel_get_ratestats(mi, mi->max_tp_rate);
if (rate->attempts > 30 &&
MINSTREL_FRAC(rate->success, rate->attempts) <
- MINSTREL_FRAC(20, 100))
+ MINSTREL_FRAC(20, 100)) {
minstrel_downgrade_rate(mi, &mi->max_tp_rate, true);
+ update = true;
+ }
rate2 = minstrel_get_ratestats(mi, mi->max_tp_rate2);
if (rate2->attempts > 30 &&
MINSTREL_FRAC(rate2->success, rate2->attempts) <
- MINSTREL_FRAC(20, 100))
+ MINSTREL_FRAC(20, 100)) {
minstrel_downgrade_rate(mi, &mi->max_tp_rate2, false);
+ update = true;
+ }
if (time_after(jiffies, mi->stats_update + (mp->update_interval / 2 * HZ) / 1000)) {
+ update = true;
minstrel_ht_update_stats(mp, mi);
if (!(info->flags & IEEE80211_TX_CTL_AMPDU) &&
mi->max_prob_rate / MCS_GROUP_RATES != MINSTREL_CCK_GROUP)
minstrel_aggr_check(sta, skb);
}
+
+ if (update)
+ minstrel_ht_update_rates(mp, mi);
}
static void
@@ -536,7 +567,7 @@ minstrel_calc_retransmit(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
mr->retry_updated = true;
group = &minstrel_mcs_groups[index / MCS_GROUP_RATES];
- tx_time_data = group->duration[index % MCS_GROUP_RATES] * ampdu_len;
+ tx_time_data = group->duration[index % MCS_GROUP_RATES] * ampdu_len / 1000;
/* Contention time for first 2 tries */
ctime = (t_slot * cw) >> 1;
@@ -572,36 +603,71 @@ minstrel_calc_retransmit(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
static void
minstrel_ht_set_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
- struct ieee80211_tx_rate *rate, int index,
- bool sample, bool rtscts)
+ struct ieee80211_sta_rates *ratetbl, int offset, int index)
{
const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES];
struct minstrel_rate_stats *mr;
+ u8 idx;
+ u16 flags;
mr = minstrel_get_ratestats(mi, index);
if (!mr->retry_updated)
minstrel_calc_retransmit(mp, mi, index);
- if (sample)
- rate->count = 1;
- else if (mr->probability < MINSTREL_FRAC(20, 100))
- rate->count = 2;
- else if (rtscts)
- rate->count = mr->retry_count_rtscts;
- else
- rate->count = mr->retry_count;
-
- rate->flags = 0;
- if (rtscts)
- rate->flags |= IEEE80211_TX_RC_USE_RTS_CTS;
+ if (mr->probability < MINSTREL_FRAC(20, 100) || !mr->retry_count) {
+ ratetbl->rate[offset].count = 2;
+ ratetbl->rate[offset].count_rts = 2;
+ ratetbl->rate[offset].count_cts = 2;
+ } else {
+ ratetbl->rate[offset].count = mr->retry_count;
+ ratetbl->rate[offset].count_cts = mr->retry_count;
+ ratetbl->rate[offset].count_rts = mr->retry_count_rtscts;
+ }
if (index / MCS_GROUP_RATES == MINSTREL_CCK_GROUP) {
- rate->idx = mp->cck_rates[index % ARRAY_SIZE(mp->cck_rates)];
+ idx = mp->cck_rates[index % ARRAY_SIZE(mp->cck_rates)];
+ flags = 0;
+ } else {
+ idx = index % MCS_GROUP_RATES +
+ (group->streams - 1) * MCS_GROUP_RATES;
+ flags = IEEE80211_TX_RC_MCS | group->flags;
+ }
+
+ if (offset > 0) {
+ ratetbl->rate[offset].count = ratetbl->rate[offset].count_rts;
+ flags |= IEEE80211_TX_RC_USE_RTS_CTS;
+ }
+
+ ratetbl->rate[offset].idx = idx;
+ ratetbl->rate[offset].flags = flags;
+}
+
+static void
+minstrel_ht_update_rates(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
+{
+ struct ieee80211_sta_rates *rates;
+ int i = 0;
+
+ rates = kzalloc(sizeof(*rates), GFP_ATOMIC);
+ if (!rates)
return;
+
+ /* Start with max_tp_rate */
+ minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_tp_rate);
+
+ if (mp->hw->max_rates >= 3) {
+ /* At least 3 tx rates supported, use max_tp_rate2 next */
+ minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_tp_rate2);
}
- rate->flags |= IEEE80211_TX_RC_MCS | group->flags;
- rate->idx = index % MCS_GROUP_RATES + (group->streams - 1) * MCS_GROUP_RATES;
+ if (mp->hw->max_rates >= 2) {
+ /*
+ * At least 2 tx rates supported, use max_prob_rate next */
+ minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_prob_rate);
+ }
+
+ rates->rate[i].idx = -1;
+ rate_control_set_rates(mp->hw, mi->sta, rates);
}
static inline int
@@ -616,6 +682,7 @@ minstrel_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
{
struct minstrel_rate_stats *mr;
struct minstrel_mcs_group_data *mg;
+ unsigned int sample_dur, sample_group;
int sample_idx = 0;
if (mi->sample_wait > 0) {
@@ -626,39 +693,46 @@ minstrel_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
if (!mi->sample_tries)
return -1;
- mi->sample_tries--;
mg = &mi->groups[mi->sample_group];
sample_idx = sample_table[mg->column][mg->index];
mr = &mg->rates[sample_idx];
- sample_idx += mi->sample_group * MCS_GROUP_RATES;
+ sample_group = mi->sample_group;
+ sample_idx += sample_group * MCS_GROUP_RATES;
minstrel_next_sample_idx(mi);
/*
* Sampling might add some overhead (RTS, no aggregation)
* to the frame. Hence, don't use sampling for the currently
- * used max TP rate.
+ * used rates.
*/
- if (sample_idx == mi->max_tp_rate)
+ if (sample_idx == mi->max_tp_rate ||
+ sample_idx == mi->max_tp_rate2 ||
+ sample_idx == mi->max_prob_rate)
return -1;
+
/*
- * When not using MRR, do not sample if the probability is already
- * higher than 95% to avoid wasting airtime
+ * Do not sample if the probability is already higher than 95%
+ * to avoid wasting airtime.
*/
- if (!mp->has_mrr && (mr->probability > MINSTREL_FRAC(95, 100)))
+ if (mr->probability > MINSTREL_FRAC(95, 100))
return -1;
/*
* Make sure that lower rates get sampled only occasionally,
* if the link is working perfectly.
*/
- if (minstrel_get_duration(sample_idx) >
- minstrel_get_duration(mi->max_tp_rate)) {
+ sample_dur = minstrel_get_duration(sample_idx);
+ if (sample_dur >= minstrel_get_duration(mi->max_tp_rate2) &&
+ (mi->max_prob_streams <
+ minstrel_mcs_groups[sample_group].streams ||
+ sample_dur >= minstrel_get_duration(mi->max_prob_rate))) {
if (mr->sample_skipped < 20)
return -1;
if (mi->sample_slow++ > 2)
return -1;
}
+ mi->sample_tries--;
return sample_idx;
}
@@ -683,13 +757,13 @@ static void
minstrel_ht_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta,
struct ieee80211_tx_rate_control *txrc)
{
+ const struct mcs_group *sample_group;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
- struct ieee80211_tx_rate *ar = info->status.rates;
+ struct ieee80211_tx_rate *rate = &info->status.rates[0];
struct minstrel_ht_sta_priv *msp = priv_sta;
struct minstrel_ht_sta *mi = &msp->ht;
struct minstrel_priv *mp = priv;
int sample_idx;
- bool sample = false;
if (rate_control_send_low(sta, priv_sta, txrc))
return;
@@ -717,51 +791,6 @@ minstrel_ht_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta,
}
#endif
- if (sample_idx >= 0) {
- sample = true;
- minstrel_ht_set_rate(mp, mi, &ar[0], sample_idx,
- true, false);
- info->flags |= IEEE80211_TX_CTL_RATE_CTRL_PROBE;
- } else {
- minstrel_ht_set_rate(mp, mi, &ar[0], mi->max_tp_rate,
- false, false);
- }
-
- if (mp->hw->max_rates >= 3) {
- /*
- * At least 3 tx rates supported, use
- * sample_rate -> max_tp_rate -> max_prob_rate for sampling and
- * max_tp_rate -> max_tp_rate2 -> max_prob_rate by default.
- */
- if (sample_idx >= 0)
- minstrel_ht_set_rate(mp, mi, &ar[1], mi->max_tp_rate,
- false, false);
- else
- minstrel_ht_set_rate(mp, mi, &ar[1], mi->max_tp_rate2,
- false, true);
-
- minstrel_ht_set_rate(mp, mi, &ar[2], mi->max_prob_rate,
- false, !sample);
-
- ar[3].count = 0;
- ar[3].idx = -1;
- } else if (mp->hw->max_rates == 2) {
- /*
- * Only 2 tx rates supported, use
- * sample_rate -> max_prob_rate for sampling and
- * max_tp_rate -> max_prob_rate by default.
- */
- minstrel_ht_set_rate(mp, mi, &ar[1], mi->max_prob_rate,
- false, !sample);
-
- ar[2].count = 0;
- ar[2].idx = -1;
- } else {
- /* Not using MRR, only use the first rate */
- ar[1].count = 0;
- ar[1].idx = -1;
- }
-
mi->total_packets++;
/* wraparound */
@@ -769,6 +798,16 @@ minstrel_ht_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta,
mi->total_packets = 0;
mi->sample_packets = 0;
}
+
+ if (sample_idx < 0)
+ return;
+
+ sample_group = &minstrel_mcs_groups[sample_idx / MCS_GROUP_RATES];
+ info->flags |= IEEE80211_TX_CTL_RATE_CTRL_PROBE;
+ rate->idx = sample_idx % MCS_GROUP_RATES +
+ (sample_group->streams - 1) * MCS_GROUP_RATES;
+ rate->flags = IEEE80211_TX_RC_MCS | sample_group->flags;
+ rate->count = 1;
}
static void
@@ -818,6 +857,8 @@ minstrel_ht_update_caps(void *priv, struct ieee80211_supported_band *sband,
msp->is_ht = true;
memset(mi, 0, sizeof(*mi));
+
+ mi->sta = sta;
mi->stats_update = jiffies;
ack_dur = ieee80211_frame_duration(sband->band, 10, 60, 1, 1);
@@ -879,6 +920,10 @@ minstrel_ht_update_caps(void *priv, struct ieee80211_supported_band *sband,
if (!n_supported)
goto use_legacy;
+ /* create an initial rate table with the lowest supported rates */
+ minstrel_ht_update_stats(mp, mi);
+ minstrel_ht_update_rates(mp, mi);
+
return;
use_legacy:
generated by cgit v1.2.3 (git 2.0.4) at 2024-05-24 17:02:54 +0000