mac80211: add the 'minstrel' rate control algorithm
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/Kconfig b/net/mac80211/Kconfig
index 8427518..7f710a2 100644
--- a/net/mac80211/Kconfig
+++ b/net/mac80211/Kconfig
@@ -22,6 +22,11 @@
mac80211 that uses a PID controller to select the TX
rate.
+config MAC80211_RC_MINSTREL
+ bool "Minstrel"
+ ---help---
+ This option enables the 'minstrel' TX rate control algorithm
+
choice
prompt "Default rate control algorithm"
default MAC80211_RC_DEFAULT_PID
@@ -39,11 +44,19 @@
default rate control algorithm. You should choose
this unless you know what you are doing.
+config MAC80211_RC_DEFAULT_MINSTREL
+ bool "Minstrel"
+ depends on MAC80211_RC_MINSTREL
+ ---help---
+ Select Minstrel as the default rate control algorithm.
+
+
endchoice
config MAC80211_RC_DEFAULT
string
default "pid" if MAC80211_RC_DEFAULT_PID
+ default "minstrel" if MAC80211_RC_DEFAULT_MINSTREL
default ""
endmenu
diff --git a/net/mac80211/Makefile b/net/mac80211/Makefile
index 2dc8f2b..31cfd1f 100644
--- a/net/mac80211/Makefile
+++ b/net/mac80211/Makefile
@@ -41,4 +41,8 @@
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
+
mac80211-$(CONFIG_MAC80211_RC_PID) += $(rc80211_pid-y)
+mac80211-$(CONFIG_MAC80211_RC_MINSTREL) += $(rc80211_minstrel-y)
diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index d608c44..ae62ad40 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -1015,6 +1015,10 @@
BUILD_BUG_ON(offsetof(struct ieee80211_tx_info, driver_data) +
IEEE80211_TX_INFO_DRIVER_DATA_SIZE > sizeof(skb->cb));
+ ret = rc80211_minstrel_init();
+ if (ret)
+ return ret;
+
ret = rc80211_pid_init();
if (ret)
return ret;
@@ -1027,6 +1031,7 @@
static void __exit ieee80211_exit(void)
{
rc80211_pid_exit();
+ rc80211_minstrel_exit();
/*
* For key todo, it'll be empty by now but the work
diff --git a/net/mac80211/rate.h b/net/mac80211/rate.h
index eb94e58..d0092f8 100644
--- a/net/mac80211/rate.h
+++ b/net/mac80211/rate.h
@@ -125,4 +125,18 @@
}
#endif
+#ifdef CONFIG_MAC80211_RC_MINSTREL
+extern int rc80211_minstrel_init(void);
+extern void rc80211_minstrel_exit(void);
+#else
+static inline int rc80211_minstrel_init(void)
+{
+ return 0;
+}
+static inline void rc80211_minstrel_exit(void)
+{
+}
+#endif
+
+
#endif /* IEEE80211_RATE_H */
diff --git a/net/mac80211/rc80211_minstrel.c b/net/mac80211/rc80211_minstrel.c
new file mode 100644
index 0000000..f6d69da
--- /dev/null
+++ b/net/mac80211/rc80211_minstrel.c
@@ -0,0 +1,583 @@
+/*
+ * Copyright (C) 2008 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.
+ *
+ * Based on minstrel.c:
+ * Copyright (C) 2005-2007 Derek Smithies <derek@indranet.co.nz>
+ * Sponsored by Indranet Technologies Ltd
+ *
+ * Based on sample.c:
+ * Copyright (c) 2005 John Bicket
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer,
+ * without modification.
+ * 2. Redistributions in binary form must reproduce at minimum a disclaimer
+ * similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
+ * redistribution must be conditioned upon including a substantially
+ * similar Disclaimer requirement for further binary redistribution.
+ * 3. Neither the names of the above-listed copyright holders nor the names
+ * of any contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * NO WARRANTY
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
+ * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
+ * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
+ * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+ * THE POSSIBILITY OF SUCH DAMAGES.
+ */
+#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"
+
+#define SAMPLE_COLUMNS 10
+#define SAMPLE_TBL(_mi, _idx, _col) \
+ _mi->sample_table[(_idx * SAMPLE_COLUMNS) + _col]
+
+/* convert mac80211 rate index to local array index */
+static inline int
+rix_to_ndx(struct minstrel_sta_info *mi, int rix)
+{
+ int i = rix;
+ for (i = rix; i >= 0; i--)
+ if (mi->r[i].rix == rix)
+ break;
+ WARN_ON(mi->r[i].rix != rix);
+ return i;
+}
+
+static inline bool
+use_low_rate(struct sk_buff *skb)
+{
+ struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
+ struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+ u16 fc;
+
+ fc = le16_to_cpu(hdr->frame_control);
+
+ return ((info->flags & IEEE80211_TX_CTL_NO_ACK) ||
+ (fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA ||
+ is_multicast_ether_addr(hdr->addr1));
+}
+
+
+static void
+minstrel_update_stats(struct minstrel_priv *mp, struct minstrel_sta_info *mi)
+{
+ u32 max_tp = 0, index_max_tp = 0, index_max_tp2 = 0;
+ u32 max_prob = 0, index_max_prob = 0;
+ u32 usecs;
+ u32 p;
+ int i;
+
+ mi->stats_update = jiffies;
+ for (i = 0; i < mi->n_rates; i++) {
+ struct minstrel_rate *mr = &mi->r[i];
+
+ usecs = mr->perfect_tx_time;
+ if (!usecs)
+ usecs = 1000000;
+
+ /* To avoid rounding issues, probabilities scale from 0 (0%)
+ * to 18000 (100%) */
+ if (mr->attempts) {
+ p = (mr->success * 18000) / mr->attempts;
+ mr->succ_hist += mr->success;
+ mr->att_hist += mr->attempts;
+ mr->cur_prob = p;
+ p = ((p * (100 - mp->ewma_level)) + (mr->probability *
+ mp->ewma_level)) / 100;
+ mr->probability = p;
+ mr->cur_tp = p * (1000000 / usecs);
+ }
+
+ mr->last_success = mr->success;
+ mr->last_attempts = mr->attempts;
+ mr->success = 0;
+ mr->attempts = 0;
+
+ /* Sample less often below the 10% chance of success.
+ * Sample less often above the 95% chance of success. */
+ if ((mr->probability > 17100) || (mr->probability < 1800)) {
+ mr->adjusted_retry_count = mr->retry_count >> 1;
+ if (mr->adjusted_retry_count > 2)
+ mr->adjusted_retry_count = 2;
+ } else {
+ mr->adjusted_retry_count = mr->retry_count;
+ }
+ if (!mr->adjusted_retry_count)
+ mr->adjusted_retry_count = 2;
+ }
+
+ for (i = 0; i < mi->n_rates; i++) {
+ struct minstrel_rate *mr = &mi->r[i];
+ if (max_tp < mr->cur_tp) {
+ index_max_tp = i;
+ max_tp = mr->cur_tp;
+ }
+ if (max_prob < mr->probability) {
+ index_max_prob = i;
+ max_prob = mr->probability;
+ }
+ }
+
+ max_tp = 0;
+ for (i = 0; i < mi->n_rates; i++) {
+ struct minstrel_rate *mr = &mi->r[i];
+
+ if (i == index_max_tp)
+ continue;
+
+ if (max_tp < mr->cur_tp) {
+ index_max_tp2 = i;
+ max_tp = mr->cur_tp;
+ }
+ }
+ mi->max_tp_rate = index_max_tp;
+ mi->max_tp_rate2 = index_max_tp2;
+ mi->max_prob_rate = index_max_prob;
+}
+
+static void
+minstrel_tx_status(void *priv, struct ieee80211_supported_band *sband,
+ struct ieee80211_sta *sta, void *priv_sta,
+ struct sk_buff *skb)
+{
+ struct minstrel_sta_info *mi = priv_sta;
+ struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+ struct ieee80211_tx_altrate *ar = info->status.retries;
+ struct minstrel_priv *mp = priv;
+ int i, ndx, tries;
+ int success = 0;
+
+ if (!info->status.excessive_retries)
+ success = 1;
+
+ if (!mp->has_mrr || (ar[0].rate_idx < 0)) {
+ ndx = rix_to_ndx(mi, info->tx_rate_idx);
+ tries = info->status.retry_count + 1;
+ mi->r[ndx].success += success;
+ mi->r[ndx].attempts += tries;
+ return;
+ }
+
+ for (i = 0; i < 4; i++) {
+ if (ar[i].rate_idx < 0)
+ break;
+
+ ndx = rix_to_ndx(mi, ar[i].rate_idx);
+ mi->r[ndx].attempts += ar[i].limit + 1;
+
+ if ((i != 3) && (ar[i + 1].rate_idx < 0))
+ mi->r[ndx].success += success;
+ }
+
+ if ((info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE) && (i >= 0))
+ mi->sample_count++;
+
+ if (mi->sample_deferred > 0)
+ mi->sample_deferred--;
+}
+
+
+static inline unsigned int
+minstrel_get_retry_count(struct minstrel_rate *mr,
+ struct ieee80211_tx_info *info)
+{
+ unsigned int retry = mr->adjusted_retry_count;
+
+ if (info->flags & IEEE80211_TX_CTL_USE_RTS_CTS)
+ retry = max(2U, min(mr->retry_count_rtscts, retry));
+ else if (info->flags & IEEE80211_TX_CTL_USE_CTS_PROTECT)
+ retry = max(2U, min(mr->retry_count_cts, retry));
+ return retry;
+}
+
+
+static int
+minstrel_get_next_sample(struct minstrel_sta_info *mi)
+{
+ unsigned int sample_ndx;
+ sample_ndx = SAMPLE_TBL(mi, mi->sample_idx, mi->sample_column);
+ mi->sample_idx++;
+ if (mi->sample_idx > (mi->n_rates - 2)) {
+ mi->sample_idx = 0;
+ mi->sample_column++;
+ if (mi->sample_column >= SAMPLE_COLUMNS)
+ mi->sample_column = 0;
+ }
+ return sample_ndx;
+}
+
+void
+minstrel_get_rate(void *priv, struct ieee80211_supported_band *sband,
+ struct ieee80211_sta *sta, void *priv_sta,
+ struct sk_buff *skb, struct rate_selection *sel)
+{
+ struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+ struct minstrel_sta_info *mi = priv_sta;
+ struct minstrel_priv *mp = priv;
+ struct ieee80211_tx_altrate *ar = info->control.retries;
+ unsigned int ndx, sample_ndx = 0;
+ bool mrr;
+ bool sample_slower = false;
+ bool sample = false;
+ int i, delta;
+ int mrr_ndx[3];
+ int sample_rate;
+
+ if (!sta || !mi || use_low_rate(skb)) {
+ sel->rate_idx = rate_lowest_index(sband, sta);
+ return;
+ }
+
+ mrr = mp->has_mrr;
+
+ /* mac80211 does not allow mrr for RTS/CTS */
+ if ((info->flags & IEEE80211_TX_CTL_USE_RTS_CTS) ||
+ (info->flags & IEEE80211_TX_CTL_USE_CTS_PROTECT))
+ mrr = false;
+
+ if (time_after(jiffies, mi->stats_update + (mp->update_interval *
+ HZ) / 1000))
+ minstrel_update_stats(mp, mi);
+
+ ndx = mi->max_tp_rate;
+
+ if (mrr)
+ sample_rate = mp->lookaround_rate_mrr;
+ else
+ sample_rate = mp->lookaround_rate;
+
+ mi->packet_count++;
+ delta = (mi->packet_count * sample_rate / 100) -
+ (mi->sample_count + mi->sample_deferred / 2);
+
+ /* delta > 0: sampling required */
+ if (delta > 0) {
+ if (mi->packet_count >= 10000) {
+ mi->sample_deferred = 0;
+ mi->sample_count = 0;
+ mi->packet_count = 0;
+ } else if (delta > mi->n_rates * 2) {
+ /* With multi-rate retry, not every planned sample
+ * attempt actually gets used, due to the way the retry
+ * chain is set up - [max_tp,sample,prob,lowest] for
+ * sample_rate < max_tp.
+ *
+ * If there's too much sampling backlog and the link
+ * starts getting worse, minstrel would start bursting
+ * out lots of sampling frames, which would result
+ * in a large throughput loss. */
+ mi->sample_count += (delta - mi->n_rates * 2);
+ }
+
+ sample_ndx = minstrel_get_next_sample(mi);
+ sample = true;
+ sample_slower = mrr && (mi->r[sample_ndx].perfect_tx_time >
+ mi->r[ndx].perfect_tx_time);
+
+ if (!sample_slower) {
+ ndx = sample_ndx;
+ mi->sample_count++;
+ } else {
+ /* Only use IEEE80211_TX_CTL_RATE_CTRL_PROBE to mark
+ * packets that have the sampling rate deferred to the
+ * second MRR stage. Increase the sample counter only
+ * if the deferred sample rate was actually used.
+ * Use the sample_deferred counter to make sure that
+ * the sampling is not done in large bursts */
+ info->flags |= IEEE80211_TX_CTL_RATE_CTRL_PROBE;
+ mi->sample_deferred++;
+ }
+ }
+ sel->rate_idx = mi->r[ndx].rix;
+ info->control.retry_limit = minstrel_get_retry_count(&mi->r[ndx], info);
+
+ if (!mrr) {
+ ar[0].rate_idx = mi->lowest_rix;
+ ar[0].limit = mp->max_retry;
+ ar[1].rate_idx = -1;
+ return;
+ }
+
+ /* MRR setup */
+ if (sample) {
+ if (sample_slower)
+ mrr_ndx[0] = sample_ndx;
+ else
+ mrr_ndx[0] = mi->max_tp_rate;
+ } else {
+ mrr_ndx[0] = mi->max_tp_rate2;
+ }
+ mrr_ndx[1] = mi->max_prob_rate;
+ mrr_ndx[2] = 0;
+ for (i = 0; i < 3; i++) {
+ ar[i].rate_idx = mi->r[mrr_ndx[i]].rix;
+ ar[i].limit = mi->r[mrr_ndx[i]].adjusted_retry_count;
+ }
+}
+
+
+static void
+calc_rate_durations(struct minstrel_sta_info *mi, struct ieee80211_local *local,
+ struct minstrel_rate *d, struct ieee80211_rate *rate)
+{
+ int erp = !!(rate->flags & IEEE80211_RATE_ERP_G);
+
+ d->perfect_tx_time = ieee80211_frame_duration(local, 1200,
+ rate->bitrate, erp, 1);
+ d->ack_time = ieee80211_frame_duration(local, 10,
+ rate->bitrate, erp, 1);
+}
+
+static void
+init_sample_table(struct minstrel_sta_info *mi)
+{
+ unsigned int i, col, new_idx;
+ unsigned int n_srates = mi->n_rates - 1;
+ u8 rnd[8];
+
+ mi->sample_column = 0;
+ mi->sample_idx = 0;
+ memset(mi->sample_table, 0, SAMPLE_COLUMNS * mi->n_rates);
+
+ for (col = 0; col < SAMPLE_COLUMNS; col++) {
+ for (i = 0; i < n_srates; i++) {
+ get_random_bytes(rnd, sizeof(rnd));
+ new_idx = (i + rnd[i & 7]) % n_srates;
+
+ while (SAMPLE_TBL(mi, new_idx, col) != 0)
+ new_idx = (new_idx + 1) % n_srates;
+
+ /* Don't sample the slowest rate (i.e. slowest base
+ * rate). We must presume that the slowest rate works
+ * fine, or else other management frames will also be
+ * failing and the link will break */
+ SAMPLE_TBL(mi, new_idx, col) = i + 1;
+ }
+ }
+}
+
+static void
+minstrel_rate_init(void *priv, struct ieee80211_supported_band *sband,
+ struct ieee80211_sta *sta, void *priv_sta)
+{
+ struct minstrel_sta_info *mi = priv_sta;
+ struct minstrel_priv *mp = priv;
+ struct minstrel_rate *mr_ctl;
+ unsigned int i, n = 0;
+ unsigned int t_slot = 9; /* FIXME: get real slot time */
+
+ mi->lowest_rix = rate_lowest_index(sband, sta);
+ mr_ctl = &mi->r[rix_to_ndx(mi, mi->lowest_rix)];
+ mi->sp_ack_dur = mr_ctl->ack_time;
+
+ for (i = 0; i < sband->n_bitrates; i++) {
+ struct minstrel_rate *mr = &mi->r[n];
+ unsigned int tx_time = 0, tx_time_cts = 0, tx_time_rtscts = 0;
+ unsigned int tx_time_single;
+ unsigned int cw = mp->cw_min;
+
+ if (!rate_supported(sta, sband->band, i))
+ continue;
+ n++;
+ memset(mr, 0, sizeof(*mr));
+
+ mr->rix = i;
+ mr->bitrate = sband->bitrates[i].bitrate / 5;
+ calc_rate_durations(mi, hw_to_local(mp->hw), mr,
+ &sband->bitrates[i]);
+
+ /* calculate maximum number of retransmissions before
+ * fallback (based on maximum segment size) */
+ mr->retry_count = 1;
+ mr->retry_count_cts = 1;
+ mr->retry_count_rtscts = 1;
+ tx_time = mr->perfect_tx_time + mi->sp_ack_dur;
+ do {
+ /* add one retransmission */
+ tx_time_single = mr->ack_time + mr->perfect_tx_time;
+
+ /* contention window */
+ tx_time_single += t_slot + min(cw, mp->cw_max);
+ cw = (cw + 1) << 1;
+
+ tx_time += tx_time_single;
+ tx_time_cts += tx_time_single + mi->sp_ack_dur;
+ tx_time_rtscts += tx_time_single + 2 * mi->sp_ack_dur;
+ if ((tx_time_cts < mp->segment_size) &&
+ (mr->retry_count_cts < mp->max_retry))
+ mr->retry_count_cts++;
+ if ((tx_time_rtscts < mp->segment_size) &&
+ (mr->retry_count_rtscts < mp->max_retry))
+ mr->retry_count_rtscts++;
+ } while ((tx_time < mp->segment_size) &&
+ (++mr->retry_count < mp->max_retry));
+ mr->adjusted_retry_count = mr->retry_count;
+ }
+
+ for (i = n; i < sband->n_bitrates; i++) {
+ struct minstrel_rate *mr = &mi->r[i];
+ mr->rix = -1;
+ }
+
+ mi->n_rates = n;
+ mi->stats_update = jiffies;
+
+ init_sample_table(mi);
+}
+
+static void *
+minstrel_alloc_sta(void *priv, struct ieee80211_sta *sta, gfp_t gfp)
+{
+ struct ieee80211_supported_band *sband;
+ struct minstrel_sta_info *mi;
+ struct minstrel_priv *mp = priv;
+ struct ieee80211_hw *hw = mp->hw;
+ int max_rates = 0;
+ int i;
+
+ mi = kzalloc(sizeof(struct minstrel_sta_info), gfp);
+ if (!mi)
+ return NULL;
+
+ for (i = 0; i < IEEE80211_NUM_BANDS; i++) {
+ sband = hw->wiphy->bands[hw->conf.channel->band];
+ if (sband->n_bitrates > max_rates)
+ max_rates = sband->n_bitrates;
+ }
+
+ mi->r = kzalloc(sizeof(struct minstrel_rate) * max_rates, gfp);
+ if (!mi->r)
+ goto error;
+
+ mi->sample_table = kmalloc(SAMPLE_COLUMNS * max_rates, gfp);
+ if (!mi->sample_table)
+ goto error1;
+
+ mi->stats_update = jiffies;
+ return mi;
+
+error1:
+ kfree(mi->r);
+error:
+ kfree(mi);
+ return NULL;
+}
+
+static void
+minstrel_free_sta(void *priv, struct ieee80211_sta *sta, void *priv_sta)
+{
+ struct minstrel_sta_info *mi = priv_sta;
+
+ kfree(mi->sample_table);
+ kfree(mi->r);
+ kfree(mi);
+}
+
+static void
+minstrel_clear(void *priv)
+{
+}
+
+static void *
+minstrel_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
+{
+ struct minstrel_priv *mp;
+
+ mp = kzalloc(sizeof(struct minstrel_priv), GFP_ATOMIC);
+ if (!mp)
+ return NULL;
+
+ /* contention window settings
+ * Just an approximation. Using the per-queue values would complicate
+ * the calculations and is probably unnecessary */
+ mp->cw_min = 15;
+ mp->cw_max = 1023;
+
+ /* number of packets (in %) to use for sampling other rates
+ * sample less often for non-mrr packets, because the overhead
+ * is much higher than with mrr */
+ mp->lookaround_rate = 5;
+ mp->lookaround_rate_mrr = 10;
+
+ /* moving average weight for EWMA */
+ mp->ewma_level = 75;
+
+ /* maximum time that the hw is allowed to stay in one MRR segment */
+ mp->segment_size = 6000;
+
+ if (hw->max_altrate_tries > 0)
+ mp->max_retry = hw->max_altrate_tries;
+ else
+ /* safe default, does not necessarily have to match hw properties */
+ mp->max_retry = 7;
+
+ if (hw->max_altrates >= 3)
+ mp->has_mrr = true;
+
+ mp->hw = hw;
+ mp->update_interval = 100;
+
+ return mp;
+}
+
+static void
+minstrel_free(void *priv)
+{
+ kfree(priv);
+}
+
+static struct rate_control_ops mac80211_minstrel = {
+ .name = "minstrel",
+ .tx_status = minstrel_tx_status,
+ .get_rate = minstrel_get_rate,
+ .rate_init = minstrel_rate_init,
+ .clear = minstrel_clear,
+ .alloc = minstrel_alloc,
+ .free = minstrel_free,
+ .alloc_sta = minstrel_alloc_sta,
+ .free_sta = minstrel_free_sta,
+#ifdef CONFIG_MAC80211_DEBUGFS
+ .add_sta_debugfs = minstrel_add_sta_debugfs,
+ .remove_sta_debugfs = minstrel_remove_sta_debugfs,
+#endif
+};
+
+int __init
+rc80211_minstrel_init(void)
+{
+ return ieee80211_rate_control_register(&mac80211_minstrel);
+}
+
+void
+rc80211_minstrel_exit(void)
+{
+ ieee80211_rate_control_unregister(&mac80211_minstrel);
+}
+
diff --git a/net/mac80211/rc80211_minstrel.h b/net/mac80211/rc80211_minstrel.h
new file mode 100644
index 0000000..9a90a6a
--- /dev/null
+++ b/net/mac80211/rc80211_minstrel.h
@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2008 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_H
+#define __RC_MINSTREL_H
+
+struct minstrel_rate {
+ int bitrate;
+ int rix;
+
+ unsigned int perfect_tx_time;
+ unsigned int ack_time;
+
+ unsigned int retry_count;
+ unsigned int retry_count_cts;
+ unsigned int retry_count_rtscts;
+ unsigned int adjusted_retry_count;
+
+ u32 success;
+ u32 attempts;
+ u32 last_attempts;
+ u32 last_success;
+
+ /* parts per thousand */
+ u32 cur_prob;
+ u32 probability;
+
+ /* per-rate throughput */
+ u32 cur_tp;
+ u32 throughput;
+
+ u64 succ_hist;
+ u64 att_hist;
+};
+
+struct minstrel_sta_info {
+ unsigned long stats_update;
+ unsigned int sp_ack_dur;
+ unsigned int rate_avg;
+
+ unsigned int lowest_rix;
+
+ unsigned int max_tp_rate;
+ unsigned int max_tp_rate2;
+ unsigned int max_prob_rate;
+ unsigned int packet_count;
+ unsigned int sample_count;
+ int sample_deferred;
+
+ unsigned int sample_idx;
+ unsigned int sample_column;
+
+ int n_rates;
+ struct minstrel_rate *r;
+
+ /* sampling table */
+ u8 *sample_table;
+
+#ifdef CONFIG_MAC80211_DEBUGFS
+ struct dentry *dbg_stats;
+#endif
+};
+
+struct minstrel_priv {
+ struct ieee80211_hw *hw;
+ bool has_mrr;
+ unsigned int cw_min;
+ unsigned int cw_max;
+ unsigned int max_retry;
+ unsigned int ewma_level;
+ unsigned int segment_size;
+ unsigned int update_interval;
+ unsigned int lookaround_rate;
+ unsigned int lookaround_rate_mrr;
+};
+
+void minstrel_add_sta_debugfs(void *priv, void *priv_sta, struct dentry *dir);
+void minstrel_remove_sta_debugfs(void *priv, void *priv_sta);
+
+#endif
diff --git a/net/mac80211/rc80211_minstrel_debugfs.c b/net/mac80211/rc80211_minstrel_debugfs.c
new file mode 100644
index 0000000..0b024cd
--- /dev/null
+++ b/net/mac80211/rc80211_minstrel_debugfs.c
@@ -0,0 +1,164 @@
+/*
+ * Copyright (C) 2008 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.
+ *
+ * Based on minstrel.c:
+ * Copyright (C) 2005-2007 Derek Smithies <derek@indranet.co.nz>
+ * Sponsored by Indranet Technologies Ltd
+ *
+ * Based on sample.c:
+ * Copyright (c) 2005 John Bicket
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer,
+ * without modification.
+ * 2. Redistributions in binary form must reproduce at minimum a disclaimer
+ * similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
+ * redistribution must be conditioned upon including a substantially
+ * similar Disclaimer requirement for further binary redistribution.
+ * 3. Neither the names of the above-listed copyright holders nor the names
+ * of any contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * NO WARRANTY
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
+ * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
+ * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
+ * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+ * THE POSSIBILITY OF SUCH DAMAGES.
+ */
+#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"
+
+struct minstrel_stats_info {
+ struct minstrel_sta_info *mi;
+ char buf[4096];
+ size_t len;
+};
+
+static int
+minstrel_stats_open(struct inode *inode, struct file *file)
+{
+ struct minstrel_sta_info *mi = inode->i_private;
+ struct minstrel_stats_info *ms;
+ unsigned int i, tp, prob, eprob;
+ char *p;
+
+ ms = kmalloc(sizeof(*ms), GFP_KERNEL);
+ if (!ms)
+ return -ENOMEM;
+
+ file->private_data = ms;
+ p = ms->buf;
+ p += sprintf(p, "rate throughput ewma prob this prob "
+ "this succ/attempt success attempts\n");
+ for (i = 0; i < mi->n_rates; i++) {
+ struct minstrel_rate *mr = &mi->r[i];
+
+ *(p++) = (i == mi->max_tp_rate) ? 'T' : ' ';
+ *(p++) = (i == mi->max_tp_rate2) ? 't' : ' ';
+ *(p++) = (i == mi->max_prob_rate) ? 'P' : ' ';
+ p += sprintf(p, "%3u%s", mr->bitrate / 2,
+ (mr->bitrate & 1 ? ".5" : " "));
+
+ tp = ((mr->cur_tp * 96) / 18000) >> 10;
+ prob = mr->cur_prob / 18;
+ eprob = mr->probability / 18;
+
+ 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,
+ mr->succ_hist,
+ mr->att_hist);
+ }
+ p += sprintf(p, "\nTotal packet count:: ideal %d "
+ "lookaround %d\n\n",
+ mi->packet_count - mi->sample_count,
+ mi->sample_count);
+ ms->len = p - ms->buf;
+
+ return 0;
+}
+
+static int
+minstrel_stats_read(struct file *file, char __user *buf, size_t len, loff_t *o)
+{
+ struct minstrel_stats_info *ms;
+ char *src;
+
+ ms = file->private_data;
+ src = ms->buf;
+
+ len = min(len, ms->len);
+ if (len <= *o)
+ return 0;
+
+ src += *o;
+ len -= *o;
+ *o += len;
+
+ if (copy_to_user(buf, src, len))
+ return -EFAULT;
+
+ return len;
+}
+
+static int
+minstrel_stats_release(struct inode *inode, struct file *file)
+{
+ struct minstrel_stats_info *ms = file->private_data;
+
+ kfree(ms);
+
+ return 0;
+}
+
+static struct file_operations minstrel_stat_fops = {
+ .owner = THIS_MODULE,
+ .open = minstrel_stats_open,
+ .read = minstrel_stats_read,
+ .release = minstrel_stats_release,
+};
+
+void
+minstrel_add_sta_debugfs(void *priv, void *priv_sta, struct dentry *dir)
+{
+ struct minstrel_sta_info *mi = priv_sta;
+
+ mi->dbg_stats = debugfs_create_file("rc_stats", S_IRUGO, dir, mi,
+ &minstrel_stat_fops);
+}
+
+void
+minstrel_remove_sta_debugfs(void *priv, void *priv_sta)
+{
+ struct minstrel_sta_info *mi = priv_sta;
+
+ debugfs_remove(mi->dbg_stats);
+}