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![Sujith Manoharan](/assets/img/avatar_default.png)
Allow drivers or rate control algorithms to specify BlockAck session timeout when initiating an ADDBA transaction. This is useful in cases where maintaining persistent BA sessions does not incur any overhead. The current timeout value of 5000 TUs is retained for all non ath9k/ath9k_htc drivers. Signed-off-by: Sujith Manoharan <Sujith.Manoharan@atheros.com> Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
835 lines
21 KiB
C
835 lines
21 KiB
C
/*
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* Copyright (C) 2010 Felix Fietkau <nbd@openwrt.org>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/netdevice.h>
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#include <linux/types.h>
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#include <linux/skbuff.h>
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#include <linux/debugfs.h>
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#include <linux/random.h>
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#include <linux/ieee80211.h>
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#include <net/mac80211.h>
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#include "rate.h"
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#include "rc80211_minstrel.h"
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#include "rc80211_minstrel_ht.h"
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#define AVG_PKT_SIZE 1200
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#define SAMPLE_COLUMNS 10
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#define EWMA_LEVEL 75
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/* Number of bits for an average sized packet */
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#define MCS_NBITS (AVG_PKT_SIZE << 3)
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/* Number of symbols for a packet with (bps) bits per symbol */
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#define MCS_NSYMS(bps) ((MCS_NBITS + (bps) - 1) / (bps))
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/* Transmission time for a packet containing (syms) symbols */
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#define MCS_SYMBOL_TIME(sgi, syms) \
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(sgi ? \
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((syms) * 18 + 4) / 5 : /* syms * 3.6 us */ \
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(syms) << 2 /* syms * 4 us */ \
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)
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/* Transmit duration for the raw data part of an average sized packet */
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#define MCS_DURATION(streams, sgi, bps) MCS_SYMBOL_TIME(sgi, MCS_NSYMS((streams) * (bps)))
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/* MCS rate information for an MCS group */
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#define MCS_GROUP(_streams, _sgi, _ht40) { \
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.streams = _streams, \
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.flags = \
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(_sgi ? IEEE80211_TX_RC_SHORT_GI : 0) | \
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(_ht40 ? IEEE80211_TX_RC_40_MHZ_WIDTH : 0), \
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.duration = { \
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MCS_DURATION(_streams, _sgi, _ht40 ? 54 : 26), \
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MCS_DURATION(_streams, _sgi, _ht40 ? 108 : 52), \
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MCS_DURATION(_streams, _sgi, _ht40 ? 162 : 78), \
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MCS_DURATION(_streams, _sgi, _ht40 ? 216 : 104), \
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MCS_DURATION(_streams, _sgi, _ht40 ? 324 : 156), \
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MCS_DURATION(_streams, _sgi, _ht40 ? 432 : 208), \
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MCS_DURATION(_streams, _sgi, _ht40 ? 486 : 234), \
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MCS_DURATION(_streams, _sgi, _ht40 ? 540 : 260) \
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} \
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}
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/*
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* To enable sufficiently targeted rate sampling, MCS rates are divided into
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* groups, based on the number of streams and flags (HT40, SGI) that they
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* use.
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*/
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const struct mcs_group minstrel_mcs_groups[] = {
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MCS_GROUP(1, 0, 0),
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MCS_GROUP(2, 0, 0),
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#if MINSTREL_MAX_STREAMS >= 3
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MCS_GROUP(3, 0, 0),
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#endif
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MCS_GROUP(1, 1, 0),
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MCS_GROUP(2, 1, 0),
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#if MINSTREL_MAX_STREAMS >= 3
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MCS_GROUP(3, 1, 0),
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#endif
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MCS_GROUP(1, 0, 1),
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MCS_GROUP(2, 0, 1),
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#if MINSTREL_MAX_STREAMS >= 3
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MCS_GROUP(3, 0, 1),
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#endif
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MCS_GROUP(1, 1, 1),
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MCS_GROUP(2, 1, 1),
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#if MINSTREL_MAX_STREAMS >= 3
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MCS_GROUP(3, 1, 1),
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#endif
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};
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static u8 sample_table[SAMPLE_COLUMNS][MCS_GROUP_RATES];
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/*
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* Perform EWMA (Exponentially Weighted Moving Average) calculation
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*/
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static int
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minstrel_ewma(int old, int new, int weight)
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{
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return (new * (100 - weight) + old * weight) / 100;
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}
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/*
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* Look up an MCS group index based on mac80211 rate information
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*/
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static int
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minstrel_ht_get_group_idx(struct ieee80211_tx_rate *rate)
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{
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int streams = (rate->idx / MCS_GROUP_RATES) + 1;
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u32 flags = IEEE80211_TX_RC_SHORT_GI | IEEE80211_TX_RC_40_MHZ_WIDTH;
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int i;
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for (i = 0; i < ARRAY_SIZE(minstrel_mcs_groups); i++) {
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if (minstrel_mcs_groups[i].streams != streams)
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continue;
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if (minstrel_mcs_groups[i].flags != (rate->flags & flags))
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continue;
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return i;
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}
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WARN_ON(1);
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return 0;
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}
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static inline struct minstrel_rate_stats *
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minstrel_get_ratestats(struct minstrel_ht_sta *mi, int index)
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{
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return &mi->groups[index / MCS_GROUP_RATES].rates[index % MCS_GROUP_RATES];
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}
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/*
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* Recalculate success probabilities and counters for a rate using EWMA
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*/
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static void
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minstrel_calc_rate_ewma(struct minstrel_priv *mp, struct minstrel_rate_stats *mr)
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{
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if (unlikely(mr->attempts > 0)) {
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mr->sample_skipped = 0;
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mr->cur_prob = MINSTREL_FRAC(mr->success, mr->attempts);
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if (!mr->att_hist)
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mr->probability = mr->cur_prob;
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else
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mr->probability = minstrel_ewma(mr->probability,
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mr->cur_prob, EWMA_LEVEL);
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mr->att_hist += mr->attempts;
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mr->succ_hist += mr->success;
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} else {
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mr->sample_skipped++;
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}
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mr->last_success = mr->success;
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mr->last_attempts = mr->attempts;
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mr->success = 0;
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mr->attempts = 0;
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}
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/*
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* Calculate throughput based on the average A-MPDU length, taking into account
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* the expected number of retransmissions and their expected length
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*/
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static void
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minstrel_ht_calc_tp(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
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int group, int rate)
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{
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struct minstrel_rate_stats *mr;
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unsigned int usecs;
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mr = &mi->groups[group].rates[rate];
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if (mr->probability < MINSTREL_FRAC(1, 10)) {
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mr->cur_tp = 0;
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return;
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}
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usecs = mi->overhead / MINSTREL_TRUNC(mi->avg_ampdu_len);
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usecs += minstrel_mcs_groups[group].duration[rate];
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mr->cur_tp = MINSTREL_TRUNC((1000000 / usecs) * mr->probability);
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}
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/*
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* Update rate statistics and select new primary rates
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*
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* Rules for rate selection:
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* - max_prob_rate must use only one stream, as a tradeoff between delivery
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* probability and throughput during strong fluctuations
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* - as long as the max prob rate has a probability of more than 3/4, pick
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* higher throughput rates, even if the probablity is a bit lower
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*/
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static void
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minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
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{
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struct minstrel_mcs_group_data *mg;
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struct minstrel_rate_stats *mr;
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int cur_prob, cur_prob_tp, cur_tp, cur_tp2;
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int group, i, index;
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if (mi->ampdu_packets > 0) {
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mi->avg_ampdu_len = minstrel_ewma(mi->avg_ampdu_len,
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MINSTREL_FRAC(mi->ampdu_len, mi->ampdu_packets), EWMA_LEVEL);
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mi->ampdu_len = 0;
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mi->ampdu_packets = 0;
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}
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mi->sample_slow = 0;
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mi->sample_count = 0;
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mi->max_tp_rate = 0;
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mi->max_tp_rate2 = 0;
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mi->max_prob_rate = 0;
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for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) {
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cur_prob = 0;
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cur_prob_tp = 0;
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cur_tp = 0;
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cur_tp2 = 0;
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mg = &mi->groups[group];
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if (!mg->supported)
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continue;
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mg->max_tp_rate = 0;
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mg->max_tp_rate2 = 0;
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mg->max_prob_rate = 0;
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mi->sample_count++;
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for (i = 0; i < MCS_GROUP_RATES; i++) {
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if (!(mg->supported & BIT(i)))
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continue;
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mr = &mg->rates[i];
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mr->retry_updated = false;
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index = MCS_GROUP_RATES * group + i;
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minstrel_calc_rate_ewma(mp, mr);
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minstrel_ht_calc_tp(mp, mi, group, i);
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if (!mr->cur_tp)
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continue;
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/* ignore the lowest rate of each single-stream group */
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if (!i && minstrel_mcs_groups[group].streams == 1)
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continue;
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if ((mr->cur_tp > cur_prob_tp && mr->probability >
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MINSTREL_FRAC(3, 4)) || mr->probability > cur_prob) {
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mg->max_prob_rate = index;
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cur_prob = mr->probability;
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cur_prob_tp = mr->cur_tp;
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}
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if (mr->cur_tp > cur_tp) {
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swap(index, mg->max_tp_rate);
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cur_tp = mr->cur_tp;
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mr = minstrel_get_ratestats(mi, index);
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}
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if (index >= mg->max_tp_rate)
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continue;
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if (mr->cur_tp > cur_tp2) {
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mg->max_tp_rate2 = index;
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cur_tp2 = mr->cur_tp;
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}
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}
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}
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/* try to sample up to half of the availble rates during each interval */
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mi->sample_count *= 4;
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cur_prob = 0;
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cur_prob_tp = 0;
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cur_tp = 0;
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cur_tp2 = 0;
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for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) {
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mg = &mi->groups[group];
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if (!mg->supported)
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continue;
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mr = minstrel_get_ratestats(mi, mg->max_prob_rate);
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if (cur_prob_tp < mr->cur_tp &&
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minstrel_mcs_groups[group].streams == 1) {
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mi->max_prob_rate = mg->max_prob_rate;
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cur_prob = mr->cur_prob;
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cur_prob_tp = mr->cur_tp;
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}
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mr = minstrel_get_ratestats(mi, mg->max_tp_rate);
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if (cur_tp < mr->cur_tp) {
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mi->max_tp_rate = mg->max_tp_rate;
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cur_tp = mr->cur_tp;
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}
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mr = minstrel_get_ratestats(mi, mg->max_tp_rate2);
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if (cur_tp2 < mr->cur_tp) {
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mi->max_tp_rate2 = mg->max_tp_rate2;
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cur_tp2 = mr->cur_tp;
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}
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}
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mi->stats_update = jiffies;
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}
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static bool
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minstrel_ht_txstat_valid(struct ieee80211_tx_rate *rate)
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{
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if (!rate->count)
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return false;
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if (rate->idx < 0)
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return false;
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return !!(rate->flags & IEEE80211_TX_RC_MCS);
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}
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static void
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minstrel_next_sample_idx(struct minstrel_ht_sta *mi)
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{
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struct minstrel_mcs_group_data *mg;
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for (;;) {
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mi->sample_group++;
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mi->sample_group %= ARRAY_SIZE(minstrel_mcs_groups);
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mg = &mi->groups[mi->sample_group];
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if (!mg->supported)
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continue;
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if (++mg->index >= MCS_GROUP_RATES) {
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mg->index = 0;
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if (++mg->column >= ARRAY_SIZE(sample_table))
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mg->column = 0;
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}
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break;
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}
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}
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static void
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minstrel_downgrade_rate(struct minstrel_ht_sta *mi, unsigned int *idx,
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bool primary)
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{
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int group, orig_group;
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orig_group = group = *idx / MCS_GROUP_RATES;
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while (group > 0) {
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group--;
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if (!mi->groups[group].supported)
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continue;
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if (minstrel_mcs_groups[group].streams >
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minstrel_mcs_groups[orig_group].streams)
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continue;
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if (primary)
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*idx = mi->groups[group].max_tp_rate;
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else
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*idx = mi->groups[group].max_tp_rate2;
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break;
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}
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}
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static void
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minstrel_aggr_check(struct minstrel_priv *mp, struct ieee80211_sta *pubsta, struct sk_buff *skb)
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{
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struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
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struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
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u16 tid;
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if (unlikely(!ieee80211_is_data_qos(hdr->frame_control)))
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return;
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if (unlikely(skb->protocol == cpu_to_be16(ETH_P_PAE)))
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return;
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tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
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if (likely(sta->ampdu_mlme.tid_tx[tid]))
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return;
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if (skb_get_queue_mapping(skb) == IEEE80211_AC_VO)
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return;
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ieee80211_start_tx_ba_session(pubsta, tid, 5000);
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}
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static void
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minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband,
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struct ieee80211_sta *sta, void *priv_sta,
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struct sk_buff *skb)
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{
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struct minstrel_ht_sta_priv *msp = priv_sta;
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struct minstrel_ht_sta *mi = &msp->ht;
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struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
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struct ieee80211_tx_rate *ar = info->status.rates;
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struct minstrel_rate_stats *rate, *rate2;
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struct minstrel_priv *mp = priv;
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bool last = false;
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int group;
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int i = 0;
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if (!msp->is_ht)
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return mac80211_minstrel.tx_status(priv, sband, sta, &msp->legacy, skb);
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/* This packet was aggregated but doesn't carry status info */
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if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
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!(info->flags & IEEE80211_TX_STAT_AMPDU))
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return;
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if (!(info->flags & IEEE80211_TX_STAT_AMPDU)) {
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info->status.ampdu_ack_len =
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(info->flags & IEEE80211_TX_STAT_ACK ? 1 : 0);
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info->status.ampdu_len = 1;
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}
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mi->ampdu_packets++;
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mi->ampdu_len += info->status.ampdu_len;
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if (!mi->sample_wait && !mi->sample_tries && mi->sample_count > 0) {
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mi->sample_wait = 16 + 2 * MINSTREL_TRUNC(mi->avg_ampdu_len);
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mi->sample_tries = 2;
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mi->sample_count--;
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}
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if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE) {
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mi->sample_packets += info->status.ampdu_len;
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minstrel_next_sample_idx(mi);
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}
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for (i = 0; !last; i++) {
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last = (i == IEEE80211_TX_MAX_RATES - 1) ||
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!minstrel_ht_txstat_valid(&ar[i + 1]);
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if (!minstrel_ht_txstat_valid(&ar[i]))
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break;
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group = minstrel_ht_get_group_idx(&ar[i]);
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rate = &mi->groups[group].rates[ar[i].idx % 8];
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if (last)
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rate->success += info->status.ampdu_ack_len;
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rate->attempts += ar[i].count * info->status.ampdu_len;
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}
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/*
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* check for sudden death of spatial multiplexing,
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* downgrade to a lower number of streams if necessary.
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*/
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rate = minstrel_get_ratestats(mi, mi->max_tp_rate);
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if (rate->attempts > 30 &&
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MINSTREL_FRAC(rate->success, rate->attempts) <
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MINSTREL_FRAC(20, 100))
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minstrel_downgrade_rate(mi, &mi->max_tp_rate, true);
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rate2 = minstrel_get_ratestats(mi, mi->max_tp_rate2);
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if (rate2->attempts > 30 &&
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MINSTREL_FRAC(rate2->success, rate2->attempts) <
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MINSTREL_FRAC(20, 100))
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minstrel_downgrade_rate(mi, &mi->max_tp_rate2, false);
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if (time_after(jiffies, mi->stats_update + (mp->update_interval / 2 * HZ) / 1000)) {
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minstrel_ht_update_stats(mp, mi);
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minstrel_aggr_check(mp, sta, skb);
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}
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}
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static void
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minstrel_calc_retransmit(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
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int index)
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{
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struct minstrel_rate_stats *mr;
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const struct mcs_group *group;
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unsigned int tx_time, tx_time_rtscts, tx_time_data;
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unsigned int cw = mp->cw_min;
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unsigned int t_slot = 9; /* FIXME */
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unsigned int ampdu_len = MINSTREL_TRUNC(mi->avg_ampdu_len);
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mr = minstrel_get_ratestats(mi, index);
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if (mr->probability < MINSTREL_FRAC(1, 10)) {
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mr->retry_count = 1;
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mr->retry_count_rtscts = 1;
|
|
return;
|
|
}
|
|
|
|
mr->retry_count = 2;
|
|
mr->retry_count_rtscts = 2;
|
|
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 = 2 * (t_slot + mi->overhead + tx_time_data);
|
|
tx_time_rtscts = 2 * (t_slot + mi->overhead_rtscts + tx_time_data);
|
|
do {
|
|
cw = (cw << 1) | 1;
|
|
cw = min(cw, mp->cw_max);
|
|
tx_time += cw + t_slot + mi->overhead;
|
|
tx_time_rtscts += cw + t_slot + mi->overhead_rtscts;
|
|
if (tx_time_rtscts < mp->segment_size)
|
|
mr->retry_count_rtscts++;
|
|
} while ((tx_time < mp->segment_size) &&
|
|
(++mr->retry_count < mp->max_retry));
|
|
}
|
|
|
|
|
|
static void
|
|
minstrel_ht_set_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
|
|
struct ieee80211_tx_rate *rate, int index,
|
|
struct ieee80211_tx_rate_control *txrc,
|
|
bool sample, bool rtscts)
|
|
{
|
|
const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES];
|
|
struct minstrel_rate_stats *mr;
|
|
|
|
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 = IEEE80211_TX_RC_MCS | group->flags;
|
|
if (txrc->short_preamble)
|
|
rate->flags |= IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
|
|
if (txrc->rts || rtscts)
|
|
rate->flags |= IEEE80211_TX_RC_USE_RTS_CTS;
|
|
rate->idx = index % MCS_GROUP_RATES + (group->streams - 1) * MCS_GROUP_RATES;
|
|
}
|
|
|
|
static inline int
|
|
minstrel_get_duration(int index)
|
|
{
|
|
const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES];
|
|
return group->duration[index % MCS_GROUP_RATES];
|
|
}
|
|
|
|
static int
|
|
minstrel_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
|
|
{
|
|
struct minstrel_rate_stats *mr;
|
|
struct minstrel_mcs_group_data *mg;
|
|
int sample_idx = 0;
|
|
|
|
if (mi->sample_wait > 0) {
|
|
mi->sample_wait--;
|
|
return -1;
|
|
}
|
|
|
|
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;
|
|
|
|
/*
|
|
* When not using MRR, 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)))
|
|
goto next;
|
|
|
|
/*
|
|
* 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)) {
|
|
if (mr->sample_skipped < 20)
|
|
goto next;
|
|
|
|
if (mi->sample_slow++ > 2)
|
|
goto next;
|
|
}
|
|
|
|
return sample_idx;
|
|
|
|
next:
|
|
minstrel_next_sample_idx(mi);
|
|
return -1;
|
|
}
|
|
|
|
static void
|
|
minstrel_ht_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta,
|
|
struct ieee80211_tx_rate_control *txrc)
|
|
{
|
|
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
|
|
struct ieee80211_tx_rate *ar = info->status.rates;
|
|
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;
|
|
|
|
if (!msp->is_ht)
|
|
return mac80211_minstrel.get_rate(priv, sta, &msp->legacy, txrc);
|
|
|
|
info->flags |= mi->tx_flags;
|
|
sample_idx = minstrel_get_sample_rate(mp, mi);
|
|
if (sample_idx >= 0) {
|
|
sample = true;
|
|
minstrel_ht_set_rate(mp, mi, &ar[0], sample_idx,
|
|
txrc, true, false);
|
|
minstrel_ht_set_rate(mp, mi, &ar[1], mi->max_tp_rate,
|
|
txrc, false, false);
|
|
info->flags |= IEEE80211_TX_CTL_RATE_CTRL_PROBE;
|
|
} else {
|
|
minstrel_ht_set_rate(mp, mi, &ar[0], mi->max_tp_rate,
|
|
txrc, false, false);
|
|
minstrel_ht_set_rate(mp, mi, &ar[1], mi->max_tp_rate2,
|
|
txrc, false, true);
|
|
}
|
|
minstrel_ht_set_rate(mp, mi, &ar[2], mi->max_prob_rate, txrc, false, !sample);
|
|
|
|
ar[3].count = 0;
|
|
ar[3].idx = -1;
|
|
|
|
mi->total_packets++;
|
|
|
|
/* wraparound */
|
|
if (mi->total_packets == ~0) {
|
|
mi->total_packets = 0;
|
|
mi->sample_packets = 0;
|
|
}
|
|
}
|
|
|
|
static void
|
|
minstrel_ht_update_caps(void *priv, struct ieee80211_supported_band *sband,
|
|
struct ieee80211_sta *sta, void *priv_sta,
|
|
enum nl80211_channel_type oper_chan_type)
|
|
{
|
|
struct minstrel_priv *mp = priv;
|
|
struct minstrel_ht_sta_priv *msp = priv_sta;
|
|
struct minstrel_ht_sta *mi = &msp->ht;
|
|
struct ieee80211_mcs_info *mcs = &sta->ht_cap.mcs;
|
|
struct ieee80211_local *local = hw_to_local(mp->hw);
|
|
u16 sta_cap = sta->ht_cap.cap;
|
|
int ack_dur;
|
|
int stbc;
|
|
int i;
|
|
|
|
/* fall back to the old minstrel for legacy stations */
|
|
if (!sta->ht_cap.ht_supported) {
|
|
msp->is_ht = false;
|
|
memset(&msp->legacy, 0, sizeof(msp->legacy));
|
|
msp->legacy.r = msp->ratelist;
|
|
msp->legacy.sample_table = msp->sample_table;
|
|
return mac80211_minstrel.rate_init(priv, sband, sta, &msp->legacy);
|
|
}
|
|
|
|
BUILD_BUG_ON(ARRAY_SIZE(minstrel_mcs_groups) !=
|
|
MINSTREL_MAX_STREAMS * MINSTREL_STREAM_GROUPS);
|
|
|
|
msp->is_ht = true;
|
|
memset(mi, 0, sizeof(*mi));
|
|
mi->stats_update = jiffies;
|
|
|
|
ack_dur = ieee80211_frame_duration(local, 10, 60, 1, 1);
|
|
mi->overhead = ieee80211_frame_duration(local, 0, 60, 1, 1) + ack_dur;
|
|
mi->overhead_rtscts = mi->overhead + 2 * ack_dur;
|
|
|
|
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;
|
|
|
|
stbc = (sta_cap & IEEE80211_HT_CAP_RX_STBC) >>
|
|
IEEE80211_HT_CAP_RX_STBC_SHIFT;
|
|
mi->tx_flags |= stbc << IEEE80211_TX_CTL_STBC_SHIFT;
|
|
|
|
if (sta_cap & IEEE80211_HT_CAP_LDPC_CODING)
|
|
mi->tx_flags |= IEEE80211_TX_CTL_LDPC;
|
|
|
|
if (oper_chan_type != NL80211_CHAN_HT40MINUS &&
|
|
oper_chan_type != NL80211_CHAN_HT40PLUS)
|
|
sta_cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(mi->groups); i++) {
|
|
u16 req = 0;
|
|
|
|
mi->groups[i].supported = 0;
|
|
if (minstrel_mcs_groups[i].flags & IEEE80211_TX_RC_SHORT_GI) {
|
|
if (minstrel_mcs_groups[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
|
|
req |= IEEE80211_HT_CAP_SGI_40;
|
|
else
|
|
req |= IEEE80211_HT_CAP_SGI_20;
|
|
}
|
|
|
|
if (minstrel_mcs_groups[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
|
|
req |= IEEE80211_HT_CAP_SUP_WIDTH_20_40;
|
|
|
|
if ((sta_cap & req) != req)
|
|
continue;
|
|
|
|
mi->groups[i].supported =
|
|
mcs->rx_mask[minstrel_mcs_groups[i].streams - 1];
|
|
}
|
|
}
|
|
|
|
static void
|
|
minstrel_ht_rate_init(void *priv, struct ieee80211_supported_band *sband,
|
|
struct ieee80211_sta *sta, void *priv_sta)
|
|
{
|
|
struct minstrel_priv *mp = priv;
|
|
|
|
minstrel_ht_update_caps(priv, sband, sta, priv_sta, mp->hw->conf.channel_type);
|
|
}
|
|
|
|
static void
|
|
minstrel_ht_rate_update(void *priv, struct ieee80211_supported_band *sband,
|
|
struct ieee80211_sta *sta, void *priv_sta,
|
|
u32 changed, enum nl80211_channel_type oper_chan_type)
|
|
{
|
|
minstrel_ht_update_caps(priv, sband, sta, priv_sta, oper_chan_type);
|
|
}
|
|
|
|
static void *
|
|
minstrel_ht_alloc_sta(void *priv, struct ieee80211_sta *sta, gfp_t gfp)
|
|
{
|
|
struct ieee80211_supported_band *sband;
|
|
struct minstrel_ht_sta_priv *msp;
|
|
struct minstrel_priv *mp = priv;
|
|
struct ieee80211_hw *hw = mp->hw;
|
|
int max_rates = 0;
|
|
int i;
|
|
|
|
for (i = 0; i < IEEE80211_NUM_BANDS; i++) {
|
|
sband = hw->wiphy->bands[i];
|
|
if (sband && sband->n_bitrates > max_rates)
|
|
max_rates = sband->n_bitrates;
|
|
}
|
|
|
|
msp = kzalloc(sizeof(struct minstrel_ht_sta), gfp);
|
|
if (!msp)
|
|
return NULL;
|
|
|
|
msp->ratelist = kzalloc(sizeof(struct minstrel_rate) * max_rates, gfp);
|
|
if (!msp->ratelist)
|
|
goto error;
|
|
|
|
msp->sample_table = kmalloc(SAMPLE_COLUMNS * max_rates, gfp);
|
|
if (!msp->sample_table)
|
|
goto error1;
|
|
|
|
return msp;
|
|
|
|
error1:
|
|
kfree(msp->ratelist);
|
|
error:
|
|
kfree(msp);
|
|
return NULL;
|
|
}
|
|
|
|
static void
|
|
minstrel_ht_free_sta(void *priv, struct ieee80211_sta *sta, void *priv_sta)
|
|
{
|
|
struct minstrel_ht_sta_priv *msp = priv_sta;
|
|
|
|
kfree(msp->sample_table);
|
|
kfree(msp->ratelist);
|
|
kfree(msp);
|
|
}
|
|
|
|
static void *
|
|
minstrel_ht_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
|
|
{
|
|
return mac80211_minstrel.alloc(hw, debugfsdir);
|
|
}
|
|
|
|
static void
|
|
minstrel_ht_free(void *priv)
|
|
{
|
|
mac80211_minstrel.free(priv);
|
|
}
|
|
|
|
static struct rate_control_ops mac80211_minstrel_ht = {
|
|
.name = "minstrel_ht",
|
|
.tx_status = minstrel_ht_tx_status,
|
|
.get_rate = minstrel_ht_get_rate,
|
|
.rate_init = minstrel_ht_rate_init,
|
|
.rate_update = minstrel_ht_rate_update,
|
|
.alloc_sta = minstrel_ht_alloc_sta,
|
|
.free_sta = minstrel_ht_free_sta,
|
|
.alloc = minstrel_ht_alloc,
|
|
.free = minstrel_ht_free,
|
|
#ifdef CONFIG_MAC80211_DEBUGFS
|
|
.add_sta_debugfs = minstrel_ht_add_sta_debugfs,
|
|
.remove_sta_debugfs = minstrel_ht_remove_sta_debugfs,
|
|
#endif
|
|
};
|
|
|
|
|
|
static void
|
|
init_sample_table(void)
|
|
{
|
|
int col, i, new_idx;
|
|
u8 rnd[MCS_GROUP_RATES];
|
|
|
|
memset(sample_table, 0xff, sizeof(sample_table));
|
|
for (col = 0; col < SAMPLE_COLUMNS; col++) {
|
|
for (i = 0; i < MCS_GROUP_RATES; i++) {
|
|
get_random_bytes(rnd, sizeof(rnd));
|
|
new_idx = (i + rnd[i]) % MCS_GROUP_RATES;
|
|
|
|
while (sample_table[col][new_idx] != 0xff)
|
|
new_idx = (new_idx + 1) % MCS_GROUP_RATES;
|
|
|
|
sample_table[col][new_idx] = i;
|
|
}
|
|
}
|
|
}
|
|
|
|
int __init
|
|
rc80211_minstrel_ht_init(void)
|
|
{
|
|
init_sample_table();
|
|
return ieee80211_rate_control_register(&mac80211_minstrel_ht);
|
|
}
|
|
|
|
void
|
|
rc80211_minstrel_ht_exit(void)
|
|
{
|
|
ieee80211_rate_control_unregister(&mac80211_minstrel_ht);
|
|
}
|