2010-05-13 10:48:03 -04:00
|
|
|
/*
|
|
|
|
* Copyright (C) 2010 Felix Fietkau <nbd@openwrt.org>
|
|
|
|
*
|
|
|
|
* 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 <linux/netdevice.h>
|
|
|
|
#include <linux/types.h>
|
|
|
|
#include <linux/skbuff.h>
|
|
|
|
#include <linux/debugfs.h>
|
|
|
|
#include <linux/random.h>
|
|
|
|
#include <linux/ieee80211.h>
|
|
|
|
#include <net/mac80211.h>
|
|
|
|
#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;
|
2010-07-01 11:18:42 -04:00
|
|
|
cur_prob_tp = mr->cur_tp;
|
2010-05-13 10:48:03 -04:00
|
|
|
}
|
|
|
|
|
|
|
|
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;
|
2010-07-01 11:18:42 -04:00
|
|
|
cur_prob_tp = mr->cur_tp;
|
2010-05-13 10:48:03 -04:00
|
|
|
}
|
|
|
|
|
|
|
|
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
|
2010-06-24 11:18:38 -04:00
|
|
|
minstrel_downgrade_rate(struct minstrel_ht_sta *mi, unsigned int *idx,
|
|
|
|
bool primary)
|
2010-05-13 10:48:03 -04:00
|
|
|
{
|
|
|
|
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;
|
2010-06-10 04:21:39 -04:00
|
|
|
if (likely(sta->ampdu_mlme.tid_tx[tid]))
|
2010-05-13 10:48:03 -04:00
|
|
|
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);
|
2010-07-01 11:19:50 -04:00
|
|
|
if (rate2->attempts > 30 &&
|
|
|
|
MINSTREL_FRAC(rate2->success, rate2->attempts) <
|
2010-05-13 10:48:03 -04:00
|
|
|
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 */
|
2010-07-22 15:36:02 -04:00
|
|
|
if (!sta->ht_cap.ht_supported) {
|
2010-05-13 10:48:03 -04:00
|
|
|
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:
|
2010-07-22 07:14:19 -04:00
|
|
|
kfree(msp->ratelist);
|
2010-05-13 10:48:03 -04:00
|
|
|
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);
|
|
|
|
}
|