Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit f4a8cd94 authored by Felix Fietkau's avatar Felix Fietkau Committed by John W. Linville
Browse files

minstrel: improve performance for non-MRR drivers 



This patch enhances minstrel's performance for non-MRR setups,
by preventing it from sampling slower rates with >95% success
probability and by putting at least 1 non-sample frame between
several sample frames.

Signed-off-by: default avatarFelix Fietkau <nbd@openwrt.org>
Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
parent 0a9542ee

net/mac80211/rc80211_minstrel.c

+25 −4
Original line number Diff line number Diff line
@@ -126,7 +126,9 @@ minstrel_update_stats(struct minstrel_priv *mp, struct minstrel_sta_info *mi) 
			mr->adjusted_retry_count = mr->retry_count >> 1;

			if (mr->adjusted_retry_count > 2)

				mr->adjusted_retry_count = 2;

			mr->sample_limit = 4;

		} else {

			mr->sample_limit = -1;

			mr->adjusted_retry_count = mr->retry_count;

		}

		if (!mr->adjusted_retry_count)
@@ -265,7 +267,8 @@ minstrel_get_rate(void *priv, struct ieee80211_sta *sta, 
			(mi->sample_count + mi->sample_deferred / 2);



	/* delta > 0: sampling required */

	if (delta > 0) {

	if ((delta > 0) && (mrr || !mi->prev_sample)) {

		struct minstrel_rate *msr;

		if (mi->packet_count >= 10000) {

			mi->sample_deferred = 0;

			mi->sample_count = 0;
@@ -284,13 +287,20 @@ minstrel_get_rate(void *priv, struct ieee80211_sta *sta, 
		}



		sample_ndx = minstrel_get_next_sample(mi);

		msr = &mi->r[sample_ndx];

		sample = true;

		sample_slower = mrr && (mi->r[sample_ndx].perfect_tx_time >

		sample_slower = mrr && (msr->perfect_tx_time >

			mi->r[ndx].perfect_tx_time);



		if (!sample_slower) {

			if (msr->sample_limit != 0) {

				ndx = sample_ndx;

				mi->sample_count++;

				if (msr->sample_limit > 0)

					msr->sample_limit--;

			} else {

				sample = false;

			}

		} else {

			/* Only use IEEE80211_TX_CTL_RATE_CTRL_PROBE to mark

			 * packets that have the sampling rate deferred to the
@@ -302,10 +312,20 @@ minstrel_get_rate(void *priv, struct ieee80211_sta *sta, 
			mi->sample_deferred++;

		}

	}

	mi->prev_sample = sample;



	/* If we're not using MRR and the sampling rate already

	 * has a probability of >95%, we shouldn't be attempting

	 * to use it, as this only wastes precious airtime */

	if (!mrr && sample && (mi->r[ndx].probability > 17100))

		ndx = mi->max_tp_rate;



	ar[0].idx = mi->r[ndx].rix;

	ar[0].count = minstrel_get_retry_count(&mi->r[ndx], info);



	if (!mrr) {

		if (!sample)

			ar[0].count = mp->max_retry;

		ar[1].idx = mi->lowest_rix;

		ar[1].count = mp->max_retry;

		return;
@@ -401,6 +421,7 @@ minstrel_rate_init(void *priv, struct ieee80211_supported_band *sband, 


		/* calculate maximum number of retransmissions before

		 * fallback (based on maximum segment size) */

		mr->sample_limit = -1;

		mr->retry_count = 1;

		mr->retry_count_cts = 1;

		mr->retry_count_rtscts = 1;

net/mac80211/rc80211_minstrel.h

+2 −0
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ struct minstrel_rate { 
	unsigned int perfect_tx_time;

	unsigned int ack_time;



	int sample_limit;

	unsigned int retry_count;

	unsigned int retry_count_cts;

	unsigned int retry_count_rtscts;
@@ -57,6 +58,7 @@ struct minstrel_sta_info { 


	int n_rates;

	struct minstrel_rate *r;

	bool prev_sample;



	/* sampling table */

	u8 *sample_table;