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-rw-r--r--package/mac80211/patches/530-minstrel_ht.patch1147
1 files changed, 0 insertions, 1147 deletions
diff --git a/package/mac80211/patches/530-minstrel_ht.patch b/package/mac80211/patches/530-minstrel_ht.patch
deleted file mode 100644
index 046e91b8c..000000000
--- a/package/mac80211/patches/530-minstrel_ht.patch
+++ /dev/null
@@ -1,1147 +0,0 @@
---- a/net/mac80211/Makefile
-+++ b/net/mac80211/Makefile
-@@ -47,8 +47,8 @@ CFLAGS_driver-trace.o := -I$(src)
- rc80211_pid-y := rc80211_pid_algo.o
- rc80211_pid-$(CONFIG_MAC80211_DEBUGFS) += rc80211_pid_debugfs.o
-
--rc80211_minstrel-y := rc80211_minstrel.o
--rc80211_minstrel-$(CONFIG_MAC80211_DEBUGFS) += rc80211_minstrel_debugfs.o
-+rc80211_minstrel-y := rc80211_minstrel.o rc80211_minstrel_ht.o
-+rc80211_minstrel-$(CONFIG_MAC80211_DEBUGFS) += rc80211_minstrel_debugfs.o rc80211_minstrel_ht_debugfs.o
-
- mac80211-$(CONFIG_MAC80211_RC_PID) += $(rc80211_pid-y)
- mac80211-$(CONFIG_MAC80211_RC_MINSTREL) += $(rc80211_minstrel-y)
---- a/net/mac80211/main.c
-+++ b/net/mac80211/main.c
-@@ -716,6 +716,10 @@ static int __init ieee80211_init(void)
- if (ret)
- return ret;
-
-+ ret = rc80211_minstrel_ht_init();
-+ if (ret)
-+ goto err_minstrel;
-+
- ret = rc80211_pid_init();
- if (ret)
- goto err_pid;
-@@ -728,6 +732,8 @@ static int __init ieee80211_init(void)
- err_netdev:
- rc80211_pid_exit();
- err_pid:
-+ rc80211_minstrel_ht_exit();
-+ err_minstrel:
- rc80211_minstrel_exit();
-
- return ret;
-@@ -736,6 +742,7 @@ static int __init ieee80211_init(void)
- static void __exit ieee80211_exit(void)
- {
- rc80211_pid_exit();
-+ rc80211_minstrel_ht_exit();
- rc80211_minstrel_exit();
-
- /*
---- a/net/mac80211/rate.h
-+++ b/net/mac80211/rate.h
-@@ -137,6 +137,8 @@ static inline void rc80211_pid_exit(void
- #ifdef CONFIG_MAC80211_RC_MINSTREL
- extern int rc80211_minstrel_init(void);
- extern void rc80211_minstrel_exit(void);
-+extern int rc80211_minstrel_ht_init(void);
-+extern void rc80211_minstrel_ht_exit(void);
- #else
- static inline int rc80211_minstrel_init(void)
- {
-@@ -145,6 +147,13 @@ static inline int rc80211_minstrel_init(
- static inline void rc80211_minstrel_exit(void)
- {
- }
-+static inline int rc80211_minstrel_ht_init(void)
-+{
-+ return 0;
-+}
-+static inline void rc80211_minstrel_ht_exit(void)
-+{
-+}
- #endif
-
-
---- /dev/null
-+++ b/net/mac80211/rc80211_minstrel_ht.c
-@@ -0,0 +1,822 @@
-+/*
-+ * 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;
-+ }
-+
-+ 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 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;
-+
-+ if (sta_cap & IEEE80211_HT_CAP_TX_STBC)
-+ mi->tx_flags |= IEEE80211_TX_CTL_STBC;
-+
-+ 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);
-+}
---- /dev/null
-+++ b/net/mac80211/rc80211_minstrel_ht.h
-@@ -0,0 +1,128 @@
-+/*
-+ * 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.
-+ */
-+
-+#ifndef __RC_MINSTREL_HT_H
-+#define __RC_MINSTREL_HT_H
-+
-+/*
-+ * The number of streams can be changed to 2 to reduce code
-+ * size and memory footprint.
-+ */
-+#define MINSTREL_MAX_STREAMS 3
-+#define MINSTREL_STREAM_GROUPS 4
-+
-+/* scaled fraction values */
-+#define MINSTREL_SCALE 16
-+#define MINSTREL_FRAC(val, div) (((val) << MINSTREL_SCALE) / div)
-+#define MINSTREL_TRUNC(val) ((val) >> MINSTREL_SCALE)
-+
-+#define MCS_GROUP_RATES 8
-+
-+struct mcs_group {
-+ u32 flags;
-+ unsigned int streams;
-+ unsigned int duration[MCS_GROUP_RATES];
-+};
-+
-+struct minstrel_rate_stats {
-+ /* current / last sampling period attempts/success counters */
-+ unsigned int attempts, last_attempts;
-+ unsigned int success, last_success;
-+
-+ /* total attempts/success counters */
-+ u64 att_hist, succ_hist;
-+
-+ /* current throughput */
-+ unsigned int cur_tp;
-+
-+ /* packet delivery probabilities */
-+ unsigned int cur_prob, probability;
-+
-+ /* maximum retry counts */
-+ unsigned int retry_count;
-+ unsigned int retry_count_rtscts;
-+
-+ bool retry_updated;
-+ u8 sample_skipped;
-+};
-+
-+struct minstrel_mcs_group_data {
-+ u8 index;
-+ u8 column;
-+
-+ /* bitfield of supported MCS rates of this group */
-+ u8 supported;
-+
-+ /* selected primary rates */
-+ unsigned int max_tp_rate;
-+ unsigned int max_tp_rate2;
-+ unsigned int max_prob_rate;
-+
-+ /* MCS rate statistics */
-+ struct minstrel_rate_stats rates[MCS_GROUP_RATES];
-+};
-+
-+struct minstrel_ht_sta {
-+ /* ampdu length (average, per sampling interval) */
-+ unsigned int ampdu_len;
-+ unsigned int ampdu_packets;
-+
-+ /* ampdu length (EWMA) */
-+ unsigned int avg_ampdu_len;
-+
-+ /* best throughput rate */
-+ unsigned int max_tp_rate;
-+
-+ /* second best throughput rate */
-+ unsigned int max_tp_rate2;
-+
-+ /* best probability rate */
-+ unsigned int max_prob_rate;
-+
-+ /* time of last status update */
-+ unsigned long stats_update;
-+
-+ /* overhead time in usec for each frame */
-+ unsigned int overhead;
-+ unsigned int overhead_rtscts;
-+
-+ unsigned int total_packets;
-+ unsigned int sample_packets;
-+
-+ /* tx flags to add for frames for this sta */
-+ u32 tx_flags;
-+
-+ u8 sample_wait;
-+ u8 sample_tries;
-+ u8 sample_count;
-+ u8 sample_slow;
-+
-+ /* current MCS group to be sampled */
-+ u8 sample_group;
-+
-+ /* MCS rate group info and statistics */
-+ struct minstrel_mcs_group_data groups[MINSTREL_MAX_STREAMS * MINSTREL_STREAM_GROUPS];
-+};
-+
-+struct minstrel_ht_sta_priv {
-+ union {
-+ struct minstrel_ht_sta ht;
-+ struct minstrel_sta_info legacy;
-+ };
-+#ifdef CONFIG_MAC80211_DEBUGFS
-+ struct dentry *dbg_stats;
-+#endif
-+ void *ratelist;
-+ void *sample_table;
-+ bool is_ht;
-+};
-+
-+void minstrel_ht_add_sta_debugfs(void *priv, void *priv_sta, struct dentry *dir);
-+void minstrel_ht_remove_sta_debugfs(void *priv, void *priv_sta);
-+
-+#endif
---- /dev/null
-+++ b/net/mac80211/rc80211_minstrel_ht_debugfs.c
-@@ -0,0 +1,120 @@
-+/*
-+ * 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/ieee80211.h>
-+#include <net/mac80211.h>
-+#include "rc80211_minstrel.h"
-+#include "rc80211_minstrel_ht.h"
-+
-+extern const struct mcs_group minstrel_mcs_groups[];
-+
-+static int
-+minstrel_ht_stats_open(struct inode *inode, struct file *file)
-+{
-+ struct minstrel_ht_sta_priv *msp = inode->i_private;
-+ struct minstrel_ht_sta *mi = &msp->ht;
-+ struct minstrel_debugfs_info *ms;
-+ unsigned int i, j, tp, prob, eprob;
-+ char *p;
-+ int ret;
-+
-+ if (!msp->is_ht) {
-+ inode->i_private = &msp->legacy;
-+ ret = minstrel_stats_open(inode, file);
-+ inode->i_private = msp;
-+ return ret;
-+ }
-+
-+ ms = kmalloc(sizeof(*ms) + 8192, GFP_KERNEL);
-+ if (!ms)
-+ return -ENOMEM;
-+
-+ file->private_data = ms;
-+ p = ms->buf;
-+ p += sprintf(p, "type rate throughput ewma prob this prob "
-+ "this succ/attempt success attempts\n");
-+ for (i = 0; i < MINSTREL_MAX_STREAMS * MINSTREL_STREAM_GROUPS; i++) {
-+ char htmode = '2';
-+ char gimode = 'L';
-+
-+ if (!mi->groups[i].supported)
-+ continue;
-+
-+ if (minstrel_mcs_groups[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
-+ htmode = '4';
-+ if (minstrel_mcs_groups[i].flags & IEEE80211_TX_RC_SHORT_GI)
-+ gimode = 'S';
-+
-+ for (j = 0; j < MCS_GROUP_RATES; j++) {
-+ struct minstrel_rate_stats *mr = &mi->groups[i].rates[j];
-+ int idx = i * MCS_GROUP_RATES + j;
-+
-+ if (!(mi->groups[i].supported & BIT(j)))
-+ continue;
-+
-+ p += sprintf(p, "HT%c0/%cGI ", htmode, gimode);
-+
-+ *(p++) = (idx == mi->max_tp_rate) ? 'T' : ' ';
-+ *(p++) = (idx == mi->max_tp_rate2) ? 't' : ' ';
-+ *(p++) = (idx == mi->max_prob_rate) ? 'P' : ' ';
-+ p += sprintf(p, "MCS%-2u", (minstrel_mcs_groups[i].streams - 1) *
-+ MCS_GROUP_RATES + j);
-+
-+ tp = mr->cur_tp / 10;
-+ prob = MINSTREL_TRUNC(mr->cur_prob * 1000);
-+ eprob = MINSTREL_TRUNC(mr->probability * 1000);
-+
-+ p += sprintf(p, " %6u.%1u %6u.%1u %6u.%1u "
-+ "%3u(%3u) %8llu %8llu\n",
-+ tp / 10, tp % 10,
-+ eprob / 10, eprob % 10,
-+ prob / 10, prob % 10,
-+ mr->last_success,
-+ mr->last_attempts,
-+ (unsigned long long)mr->succ_hist,
-+ (unsigned long long)mr->att_hist);
-+ }
-+ }
-+ p += sprintf(p, "\nTotal packet count:: ideal %d "
-+ "lookaround %d\n",
-+ max(0, (int) mi->total_packets - (int) mi->sample_packets),
-+ mi->sample_packets);
-+ p += sprintf(p, "Average A-MPDU length: %d.%d\n",
-+ MINSTREL_TRUNC(mi->avg_ampdu_len),
-+ MINSTREL_TRUNC(mi->avg_ampdu_len * 10) % 10);
-+ ms->len = p - ms->buf;
-+
-+ return 0;
-+}
-+
-+static const struct file_operations minstrel_ht_stat_fops = {
-+ .owner = THIS_MODULE,
-+ .open = minstrel_ht_stats_open,
-+ .read = minstrel_stats_read,
-+ .release = minstrel_stats_release,
-+};
-+
-+void
-+minstrel_ht_add_sta_debugfs(void *priv, void *priv_sta, struct dentry *dir)
-+{
-+ struct minstrel_ht_sta_priv *msp = priv_sta;
-+
-+ msp->dbg_stats = debugfs_create_file("rc_stats", S_IRUGO, dir, msp,
-+ &minstrel_ht_stat_fops);
-+}
-+
-+void
-+minstrel_ht_remove_sta_debugfs(void *priv, void *priv_sta)
-+{
-+ struct minstrel_ht_sta_priv *msp = priv_sta;
-+
-+ debugfs_remove(msp->dbg_stats);
-+}