mac80211: add max lossless throughput per rate
This patch adds the new statistic "maximum possible lossless
throughput" to Minstrels and Minstrel-HTs rc_stats (in debugfs). This
enables comprehensive comparison between current per-rate throughput
and max. achievable per-rate throughput.
Signed-off-by: Thomas Huehn <thomas@net.t-labs.tu-berlin.de>
Acked-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/mac80211/rc80211_minstrel.c b/net/mac80211/rc80211_minstrel.c
index 61a857b..c4a3477 100644
--- a/net/mac80211/rc80211_minstrel.c
+++ b/net/mac80211/rc80211_minstrel.c
@@ -70,7 +70,7 @@
}
/* return current EMWA throughput */
-int minstrel_get_tp_avg(struct minstrel_rate *mr)
+int minstrel_get_tp_avg(struct minstrel_rate *mr, int prob_ewma)
{
int usecs;
@@ -81,8 +81,11 @@
/* reset thr. below 10% success */
if (mr->stats.prob_ewma < MINSTREL_FRAC(10, 100))
return 0;
+
+ if (prob_ewma > MINSTREL_FRAC(90, 100))
+ return MINSTREL_TRUNC(100000 * (MINSTREL_FRAC(90, 100) / usecs));
else
- return MINSTREL_TRUNC(mr->stats.prob_ewma * (100000 / usecs));
+ return MINSTREL_TRUNC(100000 * (prob_ewma / usecs));
}
/* find & sort topmost throughput rates */
@@ -90,10 +93,14 @@
minstrel_sort_best_tp_rates(struct minstrel_sta_info *mi, int i, u8 *tp_list)
{
int j = MAX_THR_RATES;
+ struct minstrel_rate_stats *tmp_mrs = &mi->r[j - 1].stats;
+ struct minstrel_rate_stats *cur_mrs = &mi->r[i].stats;
- while (j > 0 && (minstrel_get_tp_avg(&mi->r[i]) >
- minstrel_get_tp_avg(&mi->r[tp_list[j - 1]])))
+ while (j > 0 && (minstrel_get_tp_avg(&mi->r[i], cur_mrs->prob_ewma) >
+ minstrel_get_tp_avg(&mi->r[tp_list[j - 1]], tmp_mrs->prob_ewma))) {
j--;
+ tmp_mrs = &mi->r[tp_list[j - 1]].stats;
+ }
if (j < MAX_THR_RATES - 1)
memmove(&tp_list[j + 1], &tp_list[j], MAX_THR_RATES - (j + 1));
@@ -184,6 +191,7 @@
for (i = 0; i < mi->n_rates; i++) {
struct minstrel_rate *mr = &mi->r[i];
struct minstrel_rate_stats *mrs = &mi->r[i].stats;
+ struct minstrel_rate_stats *tmp_mrs = &mi->r[tmp_prob_rate].stats;
/* Update success probabilities per rate */
minstrel_calc_rate_stats(mrs);
@@ -212,12 +220,13 @@
* (2) if all success probabilities < 95%, the rate with
* highest success probability is chosen as max_prob_rate */
if (mrs->prob_ewma >= MINSTREL_FRAC(95, 100)) {
- tmp_cur_tp = minstrel_get_tp_avg(mr);
- tmp_prob_tp = minstrel_get_tp_avg(&mi->r[tmp_prob_rate]);
+ tmp_cur_tp = minstrel_get_tp_avg(mr, mrs->prob_ewma);
+ tmp_prob_tp = minstrel_get_tp_avg(&mi->r[tmp_prob_rate],
+ tmp_mrs->prob_ewma);
if (tmp_cur_tp >= tmp_prob_tp)
tmp_prob_rate = i;
} else {
- if (mrs->prob_ewma >= mi->r[tmp_prob_rate].stats.prob_ewma)
+ if (mrs->prob_ewma >= tmp_mrs->prob_ewma)
tmp_prob_rate = i;
}
}
@@ -684,13 +693,15 @@
static u32 minstrel_get_expected_throughput(void *priv_sta)
{
struct minstrel_sta_info *mi = priv_sta;
+ struct minstrel_rate_stats *tmp_mrs;
int idx = mi->max_tp_rate[0];
int tmp_cur_tp;
/* convert pkt per sec in kbps (1200 is the average pkt size used for
* computing cur_tp
*/
- tmp_cur_tp = minstrel_get_tp_avg(&mi->r[idx]);
+ tmp_mrs = &mi->r[idx].stats;
+ tmp_cur_tp = minstrel_get_tp_avg(&mi->r[idx], tmp_mrs->prob_ewma);
tmp_cur_tp = tmp_cur_tp * 1200 * 8 / 1024;
return tmp_cur_tp;