From ec8aa669b8393b6789b1954d587c63264af7ff99 Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Thu, 13 May 2010 16:48:03 +0200 Subject: mac80211: add the minstrel_ht rate control algorithm Signed-off-by: Felix Fietkau Signed-off-by: John W. Linville --- net/mac80211/rc80211_minstrel_ht.c | 824 +++++++++++++++++++++++++++++++++++++ 1 file changed, 824 insertions(+) create mode 100644 net/mac80211/rc80211_minstrel_ht.c (limited to 'net/mac80211/rc80211_minstrel_ht.c') diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c new file mode 100644 index 000000000000..c23f08251da4 --- /dev/null +++ b/net/mac80211/rc80211_minstrel_ht.c @@ -0,0 +1,824 @@ +/* + * Copyright (C) 2010 Felix Fietkau + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include +#include +#include +#include +#include +#include +#include +#include "rate.h" +#include "rc80211_minstrel.h" +#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) + +/* 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 */ +#define MCS_SYMBOL_TIME(sgi, syms) \ + (sgi ? \ + ((syms) * 18 + 4) / 5 : /* syms * 3.6 us */ \ + (syms) << 2 /* syms * 4 us */ \ + ) + +/* Transmit duration for the raw data part of an average sized packet */ +#define MCS_DURATION(streams, sgi, bps) MCS_SYMBOL_TIME(sgi, MCS_NSYMS((streams) * (bps))) + +/* MCS rate information for an MCS group */ +#define MCS_GROUP(_streams, _sgi, _ht40) { \ + .streams = _streams, \ + .flags = \ + (_sgi ? IEEE80211_TX_RC_SHORT_GI : 0) | \ + (_ht40 ? IEEE80211_TX_RC_40_MHZ_WIDTH : 0), \ + .duration = { \ + MCS_DURATION(_streams, _sgi, _ht40 ? 54 : 26), \ + MCS_DURATION(_streams, _sgi, _ht40 ? 108 : 52), \ + MCS_DURATION(_streams, _sgi, _ht40 ? 162 : 78), \ + MCS_DURATION(_streams, _sgi, _ht40 ? 216 : 104), \ + MCS_DURATION(_streams, _sgi, _ht40 ? 324 : 156), \ + MCS_DURATION(_streams, _sgi, _ht40 ? 432 : 208), \ + MCS_DURATION(_streams, _sgi, _ht40 ? 486 : 234), \ + MCS_DURATION(_streams, _sgi, _ht40 ? 540 : 260) \ + } \ +} + +/* + * To enable sufficiently targeted rate sampling, MCS rates are divided into + * groups, based on the number of streams and flags (HT40, SGI) that they + * use. + */ +const struct mcs_group minstrel_mcs_groups[] = { + MCS_GROUP(1, 0, 0), + MCS_GROUP(2, 0, 0), +#if MINSTREL_MAX_STREAMS >= 3 + MCS_GROUP(3, 0, 0), +#endif + + MCS_GROUP(1, 1, 0), + MCS_GROUP(2, 1, 0), +#if MINSTREL_MAX_STREAMS >= 3 + MCS_GROUP(3, 1, 0), +#endif + + MCS_GROUP(1, 0, 1), + MCS_GROUP(2, 0, 1), +#if MINSTREL_MAX_STREAMS >= 3 + MCS_GROUP(3, 0, 1), +#endif + + MCS_GROUP(1, 1, 1), + MCS_GROUP(2, 1, 1), +#if MINSTREL_MAX_STREAMS >= 3 + MCS_GROUP(3, 1, 1), +#endif +}; + +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; +} + +/* + * Look up an MCS group index based on mac80211 rate information + */ +static int +minstrel_ht_get_group_idx(struct ieee80211_tx_rate *rate) +{ + int streams = (rate->idx / MCS_GROUP_RATES) + 1; + u32 flags = IEEE80211_TX_RC_SHORT_GI | IEEE80211_TX_RC_40_MHZ_WIDTH; + int i; + + for (i = 0; i < ARRAY_SIZE(minstrel_mcs_groups); i++) { + if (minstrel_mcs_groups[i].streams != streams) + continue; + if (minstrel_mcs_groups[i].flags != (rate->flags & flags)) + continue; + + return i; + } + + WARN_ON(1); + return 0; +} + +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]; +} + + +/* + * Recalculate success probabilities and counters for a rate using EWMA + */ +static void +minstrel_calc_rate_ewma(struct minstrel_priv *mp, struct minstrel_rate_stats *mr) +{ + if (unlikely(mr->attempts > 0)) { + mr->sample_skipped = 0; + mr->cur_prob = MINSTREL_FRAC(mr->success, mr->attempts); + if (!mr->att_hist) + mr->probability = mr->cur_prob; + else + mr->probability = minstrel_ewma(mr->probability, + mr->cur_prob, EWMA_LEVEL); + mr->att_hist += mr->attempts; + mr->succ_hist += mr->success; + } else { + mr->sample_skipped++; + } + mr->last_success = mr->success; + mr->last_attempts = mr->attempts; + mr->success = 0; + mr->attempts = 0; +} + +/* + * Calculate throughput based on the average A-MPDU length, taking into account + * the expected number of retransmissions and their expected length + */ +static void +minstrel_ht_calc_tp(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, + int group, int rate) +{ + struct minstrel_rate_stats *mr; + unsigned int usecs; + + mr = &mi->groups[group].rates[rate]; + + if (mr->probability < MINSTREL_FRAC(1, 10)) { + mr->cur_tp = 0; + return; + } + + usecs = mi->overhead / MINSTREL_TRUNC(mi->avg_ampdu_len); + usecs += minstrel_mcs_groups[group].duration[rate]; + mr->cur_tp = MINSTREL_TRUNC((1000000 / usecs) * mr->probability); +} + +/* + * Update rate statistics and select new primary rates + * + * Rules for rate selection: + * - max_prob_rate must use only one stream, as a tradeoff between delivery + * probability and throughput during strong fluctuations + * - as long as the max prob rate has a probability of more than 3/4, pick + * 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) +{ + struct minstrel_mcs_group_data *mg; + struct minstrel_rate_stats *mr; + int cur_prob, cur_prob_tp, cur_tp, cur_tp2; + int group, i, index; + + if (mi->ampdu_packets > 0) { + mi->avg_ampdu_len = minstrel_ewma(mi->avg_ampdu_len, + MINSTREL_FRAC(mi->ampdu_len, mi->ampdu_packets), EWMA_LEVEL); + mi->ampdu_len = 0; + mi->ampdu_packets = 0; + } + + 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++) { + cur_prob = 0; + cur_prob_tp = 0; + cur_tp = 0; + cur_tp2 = 0; + + mg = &mi->groups[group]; + 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; + + mr = &mg->rates[i]; + mr->retry_updated = false; + index = MCS_GROUP_RATES * group + i; + minstrel_calc_rate_ewma(mp, mr); + minstrel_ht_calc_tp(mp, mi, group, i); + + if (!mr->cur_tp) + continue; + + /* ignore the lowest rate of each single-stream group */ + if (!i && minstrel_mcs_groups[group].streams == 1) + continue; + + if ((mr->cur_tp > cur_prob_tp && mr->probability > + MINSTREL_FRAC(3, 4)) || mr->probability > cur_prob) { + mg->max_prob_rate = index; + cur_prob = mr->probability; + } + + if (mr->cur_tp > cur_tp) { + swap(index, mg->max_tp_rate); + cur_tp = mr->cur_tp; + mr = minstrel_get_ratestats(mi, index); + } + + if (index >= mg->max_tp_rate) + continue; + + if (mr->cur_tp > cur_tp2) { + mg->max_tp_rate2 = index; + cur_tp2 = mr->cur_tp; + } + } + } + + /* try to sample up to half of the availble rates during each interval */ + mi->sample_count *= 4; + + cur_prob = 0; + cur_prob_tp = 0; + cur_tp = 0; + cur_tp2 = 0; + 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 == 1) { + mi->max_prob_rate = mg->max_prob_rate; + cur_prob = mr->cur_prob; + } + + mr = minstrel_get_ratestats(mi, mg->max_tp_rate); + if (cur_tp < mr->cur_tp) { + mi->max_tp_rate = mg->max_tp_rate; + cur_tp = mr->cur_tp; + } + + mr = minstrel_get_ratestats(mi, mg->max_tp_rate2); + if (cur_tp2 < mr->cur_tp) { + mi->max_tp_rate2 = mg->max_tp_rate2; + cur_tp2 = mr->cur_tp; + } + } + + mi->stats_update = jiffies; +} + +static bool +minstrel_ht_txstat_valid(struct ieee80211_tx_rate *rate) +{ + if (!rate->count) + return false; + + if (rate->idx < 0) + return false; + + return !!(rate->flags & IEEE80211_TX_RC_MCS); +} + +static void +minstrel_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 (!mg->supported) + 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, int *idx, bool primary) +{ + int group, orig_group; + + orig_group = group = *idx / MCS_GROUP_RATES; + while (group > 0) { + group--; + + if (!mi->groups[group].supported) + continue; + + if (minstrel_mcs_groups[group].streams > + minstrel_mcs_groups[orig_group].streams) + continue; + + if (primary) + *idx = mi->groups[group].max_tp_rate; + else + *idx = mi->groups[group].max_tp_rate2; + break; + } +} + +static void +minstrel_aggr_check(struct minstrel_priv *mp, struct ieee80211_sta *pubsta, struct sk_buff *skb) +{ + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; + struct sta_info *sta = container_of(pubsta, struct sta_info, sta); + u16 tid; + + if (unlikely(!ieee80211_is_data_qos(hdr->frame_control))) + return; + + if (unlikely(skb->protocol == cpu_to_be16(ETH_P_PAE))) + return; + + tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; + if (likely(sta->ampdu_mlme.tid_state_tx[tid] != HT_AGG_STATE_IDLE)) + return; + + ieee80211_start_tx_ba_session(pubsta, tid); +} + +static void +minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband, + struct ieee80211_sta *sta, void *priv_sta, + struct sk_buff *skb) +{ + struct minstrel_ht_sta_priv *msp = priv_sta; + struct minstrel_ht_sta *mi = &msp->ht; + struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); + struct ieee80211_tx_rate *ar = info->status.rates; + struct minstrel_rate_stats *rate, *rate2; + struct minstrel_priv *mp = priv; + bool last = false; + int group; + int i = 0; + + if (!msp->is_ht) + return mac80211_minstrel.tx_status(priv, sband, sta, &msp->legacy, skb); + + /* This packet was aggregated but doesn't carry status info */ + if ((info->flags & IEEE80211_TX_CTL_AMPDU) && + !(info->flags & IEEE80211_TX_STAT_AMPDU)) + return; + + if (!info->status.ampdu_len) { + info->status.ampdu_ack_len = 1; + info->status.ampdu_len = 1; + } + + mi->ampdu_packets++; + mi->ampdu_len += info->status.ampdu_len; + + if (!mi->sample_wait && !mi->sample_tries && mi->sample_count > 0) { + mi->sample_wait = 4 + 2 * MINSTREL_TRUNC(mi->avg_ampdu_len); + mi->sample_tries = 3; + mi->sample_count--; + } + + if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE) { + mi->sample_packets += info->status.ampdu_len; + minstrel_next_sample_idx(mi); + } + + for (i = 0; !last; i++) { + last = (i == IEEE80211_TX_MAX_RATES - 1) || + !minstrel_ht_txstat_valid(&ar[i + 1]); + + if (!minstrel_ht_txstat_valid(&ar[i])) + break; + + group = minstrel_ht_get_group_idx(&ar[i]); + rate = &mi->groups[group].rates[ar[i].idx % 8]; + + if (last && (info->flags & IEEE80211_TX_STAT_ACK)) + rate->success += info->status.ampdu_ack_len; + + rate->attempts += ar[i].count * info->status.ampdu_len; + } + + /* + * check for sudden death of spatial multiplexing, + * downgrade to a lower number of streams if necessary. + */ + rate = minstrel_get_ratestats(mi, mi->max_tp_rate); + if (rate->attempts > 30 && + MINSTREL_FRAC(rate->success, rate->attempts) < + MINSTREL_FRAC(20, 100)) + minstrel_downgrade_rate(mi, &mi->max_tp_rate, true); + + rate2 = minstrel_get_ratestats(mi, mi->max_tp_rate2); + if (rate->attempts > 30 && + MINSTREL_FRAC(rate->success, rate->attempts) < + MINSTREL_FRAC(20, 100)) + minstrel_downgrade_rate(mi, &mi->max_tp_rate2, false); + + if (time_after(jiffies, mi->stats_update + (mp->update_interval / 2 * HZ) / 1000)) { + minstrel_ht_update_stats(mp, mi); + minstrel_aggr_check(mp, sta, skb); + } +} + +static void +minstrel_calc_retransmit(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, + int index) +{ + struct minstrel_rate_stats *mr; + const struct mcs_group *group; + unsigned int tx_time, tx_time_rtscts, tx_time_data; + unsigned int cw = mp->cw_min; + unsigned int t_slot = 9; /* FIXME */ + unsigned int ampdu_len = MINSTREL_TRUNC(mi->avg_ampdu_len); + + mr = minstrel_get_ratestats(mi, index); + if (mr->probability < MINSTREL_FRAC(1, 10)) { + mr->retry_count = 1; + 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 (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 < 10) + 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; + + 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) { + 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, true); + 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, true); + + 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 && !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->sample_table); +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); +} -- cgit v1.2.3 From a622ab72b4dcfdf53e24b16e9530cb876979a00c Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Thu, 10 Jun 2010 10:21:39 +0200 Subject: mac80211: use RCU for TX aggregation Currently we allocate some memory for each TX aggregation session and additionally keep a state bitmap indicating the state it is in. By using RCU to protect the pointer, moving the state into the structure and some locking trickery we can avoid locking when the TX agg session is fully operational. Signed-off-by: Johannes Berg Signed-off-by: John W. Linville --- net/mac80211/rc80211_minstrel_ht.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/mac80211/rc80211_minstrel_ht.c') diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c index c23f08251da4..7a04951fcb1f 100644 --- a/net/mac80211/rc80211_minstrel_ht.c +++ b/net/mac80211/rc80211_minstrel_ht.c @@ -365,7 +365,7 @@ minstrel_aggr_check(struct minstrel_priv *mp, struct ieee80211_sta *pubsta, stru return; tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; - if (likely(sta->ampdu_mlme.tid_state_tx[tid] != HT_AGG_STATE_IDLE)) + if (likely(sta->ampdu_mlme.tid_tx[tid])) return; ieee80211_start_tx_ba_session(pubsta, tid); -- cgit v1.2.3 From d5ece2150a8a1715fea3272e057c45d98edb78ea Mon Sep 17 00:00:00 2001 From: "John W. Linville" Date: Thu, 24 Jun 2010 11:18:38 -0400 Subject: minstrel_ht: make *idx unsigned in minstrel_downgrade_rate net/mac80211/rc80211_minstrel_ht.c:440:46: warning: incorrect type in argument 2 (different signedness) net/mac80211/rc80211_minstrel_ht.c:440:46: expected int *idx net/mac80211/rc80211_minstrel_ht.c:440:46: got unsigned int * net/mac80211/rc80211_minstrel_ht.c:446:46: warning: incorrect type in argument 2 (different signedness) net/mac80211/rc80211_minstrel_ht.c:446:46: expected int *idx net/mac80211/rc80211_minstrel_ht.c:446:46: got unsigned int * Signed-off-by: John W. Linville Acked-by: Felix Fietkau --- net/mac80211/rc80211_minstrel_ht.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'net/mac80211/rc80211_minstrel_ht.c') diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c index 7a04951fcb1f..52c85036660d 100644 --- a/net/mac80211/rc80211_minstrel_ht.c +++ b/net/mac80211/rc80211_minstrel_ht.c @@ -328,7 +328,8 @@ minstrel_next_sample_idx(struct minstrel_ht_sta *mi) } static void -minstrel_downgrade_rate(struct minstrel_ht_sta *mi, int *idx, bool primary) +minstrel_downgrade_rate(struct minstrel_ht_sta *mi, unsigned int *idx, + bool primary) { int group, orig_group; -- cgit v1.2.3 From 009271f9187d61c638bb4f3db9ab172c5065e542 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Thu, 1 Jul 2010 23:18:42 +0800 Subject: minstrel_ht: fix updating rate with best probability The throughput should be considered when updating rate with best probability. Signed-off-by: Ming Lei Acked-by: Felix Fietkau Signed-off-by: John W. Linville --- net/mac80211/rc80211_minstrel_ht.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'net/mac80211/rc80211_minstrel_ht.c') diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c index 52c85036660d..8fba6f4c5145 100644 --- a/net/mac80211/rc80211_minstrel_ht.c +++ b/net/mac80211/rc80211_minstrel_ht.c @@ -240,6 +240,7 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi) MINSTREL_FRAC(3, 4)) || mr->probability > cur_prob) { mg->max_prob_rate = index; cur_prob = mr->probability; + cur_prob_tp = mr->cur_tp; } if (mr->cur_tp > cur_tp) { @@ -275,6 +276,7 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi) 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); -- cgit v1.2.3 From ecc3d5ae17e62ce1250abf16ff523c677bf19e2f Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Thu, 1 Jul 2010 23:19:50 +0800 Subject: minstrel_ht: fix check for downgrading of top2 rate The check should be against current top2 rate, instead of current top rate. Signed-off-by: Ming Lei Acked-by: Felix Fietkau Signed-off-by: John W. Linville --- net/mac80211/rc80211_minstrel_ht.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'net/mac80211/rc80211_minstrel_ht.c') diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c index 8fba6f4c5145..b5ace243546c 100644 --- a/net/mac80211/rc80211_minstrel_ht.c +++ b/net/mac80211/rc80211_minstrel_ht.c @@ -443,8 +443,8 @@ minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband, minstrel_downgrade_rate(mi, &mi->max_tp_rate, true); rate2 = minstrel_get_ratestats(mi, mi->max_tp_rate2); - if (rate->attempts > 30 && - MINSTREL_FRAC(rate->success, rate->attempts) < + if (rate2->attempts > 30 && + MINSTREL_FRAC(rate2->success, rate2->attempts) < MINSTREL_FRAC(20, 100)) minstrel_downgrade_rate(mi, &mi->max_tp_rate2, false); -- cgit v1.2.3 From 00fc90c886220efe8b634d3f2a04713fcebbe2c0 Mon Sep 17 00:00:00 2001 From: "John W. Linville" Date: Thu, 22 Jul 2010 15:36:02 -0400 Subject: minstrel_ht: remove unnecessary NULL check in minstrel_ht_update_caps If sta is NULL, we will have problems long before we get here... Reported-by: Dan Carpenter Signed-off-by: John W. Linville Cc: Felix Fietkau --- net/mac80211/rc80211_minstrel_ht.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/mac80211/rc80211_minstrel_ht.c') diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c index b5ace243546c..a16694bb634b 100644 --- a/net/mac80211/rc80211_minstrel_ht.c +++ b/net/mac80211/rc80211_minstrel_ht.c @@ -636,7 +636,7 @@ minstrel_ht_update_caps(void *priv, struct ieee80211_supported_band *sband, int i; /* fall back to the old minstrel for legacy stations */ - if (sta && !sta->ht_cap.ht_supported) { + if (!sta->ht_cap.ht_supported) { msp->is_ht = false; memset(&msp->legacy, 0, sizeof(msp->legacy)); msp->legacy.r = msp->ratelist; -- cgit v1.2.3 From 7e988014cd6dec991f095305256f57168b5610e8 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Thu, 22 Jul 2010 13:14:19 +0200 Subject: mac80211: freeing the wrong variable The intent was to free "msp->ratelist" here. "msp->sample_table" is always NULL at this point. Signed-off-by: Dan Carpenter Signed-off-by: John W. Linville --- net/mac80211/rc80211_minstrel_ht.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/mac80211/rc80211_minstrel_ht.c') diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c index a16694bb634b..c5b465904e3b 100644 --- a/net/mac80211/rc80211_minstrel_ht.c +++ b/net/mac80211/rc80211_minstrel_ht.c @@ -748,7 +748,7 @@ minstrel_ht_alloc_sta(void *priv, struct ieee80211_sta *sta, gfp_t gfp) return msp; error1: - kfree(msp->sample_table); + kfree(msp->ratelist); error: kfree(msp); return NULL; -- cgit v1.2.3