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-rw-r--r--package/mac80211/src/net/mac80211/rc80211_pid_algo.c550
1 files changed, 0 insertions, 550 deletions
diff --git a/package/mac80211/src/net/mac80211/rc80211_pid_algo.c b/package/mac80211/src/net/mac80211/rc80211_pid_algo.c
deleted file mode 100644
index da8462bbd5..0000000000
--- a/package/mac80211/src/net/mac80211/rc80211_pid_algo.c
+++ /dev/null
@@ -1,550 +0,0 @@
-/*
- * Copyright 2002-2005, Instant802 Networks, Inc.
- * Copyright 2005, Devicescape Software, Inc.
- * Copyright 2007, Mattias Nissler <mattias.nissler@gmx.de>
- * Copyright 2007-2008, Stefano Brivio <stefano.brivio@polimi.it>
- *
- * 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 <net/mac80211.h>
-#include "ieee80211_rate.h"
-
-#include "rc80211_pid.h"
-
-
-/* This is an implementation of a TX rate control algorithm that uses a PID
- * controller. Given a target failed frames rate, the controller decides about
- * TX rate changes to meet the target failed frames rate.
- *
- * The controller basically computes the following:
- *
- * adj = CP * err + CI * err_avg + CD * (err - last_err) * (1 + sharpening)
- *
- * where
- * adj adjustment value that is used to switch TX rate (see below)
- * err current error: target vs. current failed frames percentage
- * last_err last error
- * err_avg average (i.e. poor man's integral) of recent errors
- * sharpening non-zero when fast response is needed (i.e. right after
- * association or no frames sent for a long time), heading
- * to zero over time
- * CP Proportional coefficient
- * CI Integral coefficient
- * CD Derivative coefficient
- *
- * CP, CI, CD are subject to careful tuning.
- *
- * The integral component uses a exponential moving average approach instead of
- * an actual sliding window. The advantage is that we don't need to keep an
- * array of the last N error values and computation is easier.
- *
- * Once we have the adj value, we map it to a rate by means of a learning
- * algorithm. This algorithm keeps the state of the percentual failed frames
- * difference between rates. The behaviour of the lowest available rate is kept
- * as a reference value, and every time we switch between two rates, we compute
- * the difference between the failed frames each rate exhibited. By doing so,
- * we compare behaviours which different rates exhibited in adjacent timeslices,
- * thus the comparison is minimally affected by external conditions. This
- * difference gets propagated to the whole set of measurements, so that the
- * reference is always the same. Periodically, we normalize this set so that
- * recent events weigh the most. By comparing the adj value with this set, we
- * avoid pejorative switches to lower rates and allow for switches to higher
- * rates if they behaved well.
- *
- * Note that for the computations we use a fixed-point representation to avoid
- * floating point arithmetic. Hence, all values are shifted left by
- * RC_PID_ARITH_SHIFT.
- */
-
-
-/* Adjust the rate while ensuring that we won't switch to a lower rate if it
- * exhibited a worse failed frames behaviour and we'll choose the highest rate
- * whose failed frames behaviour is not worse than the one of the original rate
- * target. While at it, check that the new rate is valid. */
-static void rate_control_pid_adjust_rate(struct ieee80211_local *local,
- struct sta_info *sta, int adj,
- struct rc_pid_rateinfo *rinfo)
-{
- struct ieee80211_sub_if_data *sdata;
- struct ieee80211_supported_band *sband;
- int cur_sorted, new_sorted, probe, tmp, n_bitrates, band;
- int cur = sta->txrate_idx;
-
- sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
- sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
- band = sband->band;
- n_bitrates = sband->n_bitrates;
-
- /* Map passed arguments to sorted values. */
- cur_sorted = rinfo[cur].rev_index;
- new_sorted = cur_sorted + adj;
-
- /* Check limits. */
- if (new_sorted < 0)
- new_sorted = rinfo[0].rev_index;
- else if (new_sorted >= n_bitrates)
- new_sorted = rinfo[n_bitrates - 1].rev_index;
-
- tmp = new_sorted;
-
- if (adj < 0) {
- /* Ensure that the rate decrease isn't disadvantageous. */
- for (probe = cur_sorted; probe >= new_sorted; probe--)
- if (rinfo[probe].diff <= rinfo[cur_sorted].diff &&
- rate_supported(sta, band, rinfo[probe].index))
- tmp = probe;
- } else {
- /* Look for rate increase with zero (or below) cost. */
- for (probe = new_sorted + 1; probe < n_bitrates; probe++)
- if (rinfo[probe].diff <= rinfo[new_sorted].diff &&
- rate_supported(sta, band, rinfo[probe].index))
- tmp = probe;
- }
-
- /* Fit the rate found to the nearest supported rate. */
- do {
- if (rate_supported(sta, band, rinfo[tmp].index)) {
- sta->txrate_idx = rinfo[tmp].index;
- break;
- }
- if (adj < 0)
- tmp--;
- else
- tmp++;
- } while (tmp < n_bitrates && tmp >= 0);
-
-#ifdef CONFIG_MAC80211_DEBUGFS
- rate_control_pid_event_rate_change(
- &((struct rc_pid_sta_info *)sta->rate_ctrl_priv)->events,
- sta->txrate_idx, sband->bitrates[sta->txrate_idx].bitrate);
-#endif
-}
-
-/* Normalize the failed frames per-rate differences. */
-static void rate_control_pid_normalize(struct rc_pid_info *pinfo, int l)
-{
- int i, norm_offset = pinfo->norm_offset;
- struct rc_pid_rateinfo *r = pinfo->rinfo;
-
- if (r[0].diff > norm_offset)
- r[0].diff -= norm_offset;
- else if (r[0].diff < -norm_offset)
- r[0].diff += norm_offset;
- for (i = 0; i < l - 1; i++)
- if (r[i + 1].diff > r[i].diff + norm_offset)
- r[i + 1].diff -= norm_offset;
- else if (r[i + 1].diff <= r[i].diff)
- r[i + 1].diff += norm_offset;
-}
-
-static void rate_control_pid_sample(struct rc_pid_info *pinfo,
- struct ieee80211_local *local,
- struct sta_info *sta)
-{
- struct rc_pid_sta_info *spinfo = sta->rate_ctrl_priv;
- struct rc_pid_rateinfo *rinfo = pinfo->rinfo;
- struct ieee80211_supported_band *sband;
- u32 pf;
- s32 err_avg;
- u32 err_prop;
- u32 err_int;
- u32 err_der;
- int adj, i, j, tmp;
- unsigned long period;
-
- sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
- spinfo = sta->rate_ctrl_priv;
-
- /* In case nothing happened during the previous control interval, turn
- * the sharpening factor on. */
- period = (HZ * pinfo->sampling_period + 500) / 1000;
- if (!period)
- period = 1;
- if (jiffies - spinfo->last_sample > 2 * period)
- spinfo->sharp_cnt = pinfo->sharpen_duration;
-
- spinfo->last_sample = jiffies;
-
- /* This should never happen, but in case, we assume the old sample is
- * still a good measurement and copy it. */
- if (unlikely(spinfo->tx_num_xmit == 0))
- pf = spinfo->last_pf;
- else {
- pf = spinfo->tx_num_failed * 100 / spinfo->tx_num_xmit;
- pf <<= RC_PID_ARITH_SHIFT;
- }
-
- spinfo->tx_num_xmit = 0;
- spinfo->tx_num_failed = 0;
-
- /* If we just switched rate, update the rate behaviour info. */
- if (pinfo->oldrate != sta->txrate_idx) {
-
- i = rinfo[pinfo->oldrate].rev_index;
- j = rinfo[sta->txrate_idx].rev_index;
-
- tmp = (pf - spinfo->last_pf);
- tmp = RC_PID_DO_ARITH_RIGHT_SHIFT(tmp, RC_PID_ARITH_SHIFT);
-
- rinfo[j].diff = rinfo[i].diff + tmp;
- pinfo->oldrate = sta->txrate_idx;
- }
- rate_control_pid_normalize(pinfo, sband->n_bitrates);
-
- /* Compute the proportional, integral and derivative errors. */
- err_prop = (pinfo->target << RC_PID_ARITH_SHIFT) - pf;
-
- err_avg = spinfo->err_avg_sc >> pinfo->smoothing_shift;
- spinfo->err_avg_sc = spinfo->err_avg_sc - err_avg + err_prop;
- err_int = spinfo->err_avg_sc >> pinfo->smoothing_shift;
-
- err_der = (pf - spinfo->last_pf) *
- (1 + pinfo->sharpen_factor * spinfo->sharp_cnt);
- spinfo->last_pf = pf;
- if (spinfo->sharp_cnt)
- spinfo->sharp_cnt--;
-
-#ifdef CONFIG_MAC80211_DEBUGFS
- rate_control_pid_event_pf_sample(&spinfo->events, pf, err_prop, err_int,
- err_der);
-#endif
-
- /* Compute the controller output. */
- adj = (err_prop * pinfo->coeff_p + err_int * pinfo->coeff_i
- + err_der * pinfo->coeff_d);
- adj = RC_PID_DO_ARITH_RIGHT_SHIFT(adj, 2 * RC_PID_ARITH_SHIFT);
-
- /* Change rate. */
- if (adj)
- rate_control_pid_adjust_rate(local, sta, adj, rinfo);
-}
-
-static void rate_control_pid_tx_status(void *priv, struct net_device *dev,
- struct sk_buff *skb,
- struct ieee80211_tx_status *status)
-{
- struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
- struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
- struct ieee80211_sub_if_data *sdata;
- struct rc_pid_info *pinfo = priv;
- struct sta_info *sta;
- struct rc_pid_sta_info *spinfo;
- unsigned long period;
- struct ieee80211_supported_band *sband;
-
- sta = sta_info_get(local, hdr->addr1);
- sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
-
- if (!sta)
- return;
-
- /* Don't update the state if we're not controlling the rate. */
- sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
- if (sdata->bss && sdata->bss->force_unicast_rateidx > -1) {
- sta->txrate_idx = sdata->bss->max_ratectrl_rateidx;
- return;
- }
-
- /* Ignore all frames that were sent with a different rate than the rate
- * we currently advise mac80211 to use. */
- if (status->control.tx_rate != &sband->bitrates[sta->txrate_idx])
- goto ignore;
-
- spinfo = sta->rate_ctrl_priv;
- spinfo->tx_num_xmit++;
-
-#ifdef CONFIG_MAC80211_DEBUGFS
- rate_control_pid_event_tx_status(&spinfo->events, status);
-#endif
-
- /* We count frames that totally failed to be transmitted as two bad
- * frames, those that made it out but had some retries as one good and
- * one bad frame. */
- if (status->excessive_retries) {
- spinfo->tx_num_failed += 2;
- spinfo->tx_num_xmit++;
- } else if (status->retry_count) {
- spinfo->tx_num_failed++;
- spinfo->tx_num_xmit++;
- }
-
- if (status->excessive_retries) {
- sta->tx_retry_failed++;
- sta->tx_num_consecutive_failures++;
- sta->tx_num_mpdu_fail++;
- } else {
- sta->last_ack_rssi[0] = sta->last_ack_rssi[1];
- sta->last_ack_rssi[1] = sta->last_ack_rssi[2];
- sta->last_ack_rssi[2] = status->ack_signal;
- sta->tx_num_consecutive_failures = 0;
- sta->tx_num_mpdu_ok++;
- }
- sta->tx_retry_count += status->retry_count;
- sta->tx_num_mpdu_fail += status->retry_count;
-
- /* Update PID controller state. */
- period = (HZ * pinfo->sampling_period + 500) / 1000;
- if (!period)
- period = 1;
- if (time_after(jiffies, spinfo->last_sample + period))
- rate_control_pid_sample(pinfo, local, sta);
-
-ignore:
- sta_info_put(sta);
-}
-
-static void rate_control_pid_get_rate(void *priv, struct net_device *dev,
- struct ieee80211_supported_band *sband,
- struct sk_buff *skb,
- struct rate_selection *sel)
-{
- struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
- struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
- struct ieee80211_sub_if_data *sdata;
- struct sta_info *sta;
- int rateidx;
- u16 fc;
-
- sta = sta_info_get(local, hdr->addr1);
-
- /* Send management frames and broadcast/multicast data using lowest
- * rate. */
- fc = le16_to_cpu(hdr->frame_control);
- if ((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA ||
- is_multicast_ether_addr(hdr->addr1) || !sta) {
- sel->rate = rate_lowest(local, sband, sta);
- if (sta)
- sta_info_put(sta);
- return;
- }
-
- /* If a forced rate is in effect, select it. */
- sdata = IEEE80211_DEV_TO_SUB_IF(dev);
- if (sdata->bss && sdata->bss->force_unicast_rateidx > -1)
- sta->txrate_idx = sdata->bss->force_unicast_rateidx;
-
- rateidx = sta->txrate_idx;
-
- if (rateidx >= sband->n_bitrates)
- rateidx = sband->n_bitrates - 1;
-
- sta->last_txrate_idx = rateidx;
-
- sta_info_put(sta);
-
- sel->rate = &sband->bitrates[rateidx];
-
-#ifdef CONFIG_MAC80211_DEBUGFS
- rate_control_pid_event_tx_rate(
- &((struct rc_pid_sta_info *) sta->rate_ctrl_priv)->events,
- rateidx, sband->bitrates[rateidx].bitrate);
-#endif
-}
-
-static void rate_control_pid_rate_init(void *priv, void *priv_sta,
- struct ieee80211_local *local,
- struct sta_info *sta)
-{
- /* TODO: This routine should consider using RSSI from previous packets
- * as we need to have IEEE 802.1X auth succeed immediately after assoc..
- * Until that method is implemented, we will use the lowest supported
- * rate as a workaround. */
- struct ieee80211_supported_band *sband;
-
- sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
- sta->txrate_idx = rate_lowest_index(local, sband, sta);
-}
-
-static void *rate_control_pid_alloc(struct ieee80211_local *local)
-{
- struct rc_pid_info *pinfo;
- struct rc_pid_rateinfo *rinfo;
- struct ieee80211_supported_band *sband;
- int i, j, tmp;
- bool s;
-#ifdef CONFIG_MAC80211_DEBUGFS
- struct rc_pid_debugfs_entries *de;
-#endif
-
- sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
-
- pinfo = kmalloc(sizeof(*pinfo), GFP_ATOMIC);
- if (!pinfo)
- return NULL;
-
- /* We can safely assume that sband won't change unless we get
- * reinitialized. */
- rinfo = kmalloc(sizeof(*rinfo) * sband->n_bitrates, GFP_ATOMIC);
- if (!rinfo) {
- kfree(pinfo);
- return NULL;
- }
-
- /* Sort the rates. This is optimized for the most common case (i.e.
- * almost-sorted CCK+OFDM rates). Kind of bubble-sort with reversed
- * mapping too. */
- for (i = 0; i < sband->n_bitrates; i++) {
- rinfo[i].index = i;
- rinfo[i].rev_index = i;
- if (pinfo->fast_start)
- rinfo[i].diff = 0;
- else
- rinfo[i].diff = i * pinfo->norm_offset;
- }
- for (i = 1; i < sband->n_bitrates; i++) {
- s = 0;
- for (j = 0; j < sband->n_bitrates - i; j++)
- if (unlikely(sband->bitrates[rinfo[j].index].bitrate >
- sband->bitrates[rinfo[j + 1].index].bitrate)) {
- tmp = rinfo[j].index;
- rinfo[j].index = rinfo[j + 1].index;
- rinfo[j + 1].index = tmp;
- rinfo[rinfo[j].index].rev_index = j;
- rinfo[rinfo[j + 1].index].rev_index = j + 1;
- s = 1;
- }
- if (!s)
- break;
- }
-
- pinfo->target = RC_PID_TARGET_PF;
- pinfo->sampling_period = RC_PID_INTERVAL;
- pinfo->coeff_p = RC_PID_COEFF_P;
- pinfo->coeff_i = RC_PID_COEFF_I;
- pinfo->coeff_d = RC_PID_COEFF_D;
- pinfo->smoothing_shift = RC_PID_SMOOTHING_SHIFT;
- pinfo->sharpen_factor = RC_PID_SHARPENING_FACTOR;
- pinfo->sharpen_duration = RC_PID_SHARPENING_DURATION;
- pinfo->norm_offset = RC_PID_NORM_OFFSET;
- pinfo->fast_start = RC_PID_FAST_START;
- pinfo->rinfo = rinfo;
- pinfo->oldrate = 0;
-
-#ifdef CONFIG_MAC80211_DEBUGFS
- de = &pinfo->dentries;
- de->dir = debugfs_create_dir("rc80211_pid",
- local->hw.wiphy->debugfsdir);
- de->target = debugfs_create_u32("target_pf", S_IRUSR | S_IWUSR,
- de->dir, &pinfo->target);
- de->sampling_period = debugfs_create_u32("sampling_period",
- S_IRUSR | S_IWUSR, de->dir,
- &pinfo->sampling_period);
- de->coeff_p = debugfs_create_u32("coeff_p", S_IRUSR | S_IWUSR,
- de->dir, &pinfo->coeff_p);
- de->coeff_i = debugfs_create_u32("coeff_i", S_IRUSR | S_IWUSR,
- de->dir, &pinfo->coeff_i);
- de->coeff_d = debugfs_create_u32("coeff_d", S_IRUSR | S_IWUSR,
- de->dir, &pinfo->coeff_d);
- de->smoothing_shift = debugfs_create_u32("smoothing_shift",
- S_IRUSR | S_IWUSR, de->dir,
- &pinfo->smoothing_shift);
- de->sharpen_factor = debugfs_create_u32("sharpen_factor",
- S_IRUSR | S_IWUSR, de->dir,
- &pinfo->sharpen_factor);
- de->sharpen_duration = debugfs_create_u32("sharpen_duration",
- S_IRUSR | S_IWUSR, de->dir,
- &pinfo->sharpen_duration);
- de->norm_offset = debugfs_create_u32("norm_offset",
- S_IRUSR | S_IWUSR, de->dir,
- &pinfo->norm_offset);
- de->fast_start = debugfs_create_bool("fast_start",
- S_IRUSR | S_IWUSR, de->dir,
- &pinfo->fast_start);
-#endif
-
- return pinfo;
-}
-
-static void rate_control_pid_free(void *priv)
-{
- struct rc_pid_info *pinfo = priv;
-#ifdef CONFIG_MAC80211_DEBUGFS
- struct rc_pid_debugfs_entries *de = &pinfo->dentries;
-
- debugfs_remove(de->fast_start);
- debugfs_remove(de->norm_offset);
- debugfs_remove(de->sharpen_duration);
- debugfs_remove(de->sharpen_factor);
- debugfs_remove(de->smoothing_shift);
- debugfs_remove(de->coeff_d);
- debugfs_remove(de->coeff_i);
- debugfs_remove(de->coeff_p);
- debugfs_remove(de->sampling_period);
- debugfs_remove(de->target);
- debugfs_remove(de->dir);
-#endif
-
- kfree(pinfo->rinfo);
- kfree(pinfo);
-}
-
-static void rate_control_pid_clear(void *priv)
-{
-}
-
-static void *rate_control_pid_alloc_sta(void *priv, gfp_t gfp)
-{
- struct rc_pid_sta_info *spinfo;
-
- spinfo = kzalloc(sizeof(*spinfo), gfp);
- if (spinfo == NULL)
- return NULL;
-
- spinfo->last_sample = jiffies;
-
-#ifdef CONFIG_MAC80211_DEBUGFS
- spin_lock_init(&spinfo->events.lock);
- init_waitqueue_head(&spinfo->events.waitqueue);
-#endif
-
- return spinfo;
-}
-
-static void rate_control_pid_free_sta(void *priv, void *priv_sta)
-{
- struct rc_pid_sta_info *spinfo = priv_sta;
- kfree(spinfo);
-}
-
-static struct rate_control_ops mac80211_rcpid = {
- .name = "pid",
- .tx_status = rate_control_pid_tx_status,
- .get_rate = rate_control_pid_get_rate,
- .rate_init = rate_control_pid_rate_init,
- .clear = rate_control_pid_clear,
- .alloc = rate_control_pid_alloc,
- .free = rate_control_pid_free,
- .alloc_sta = rate_control_pid_alloc_sta,
- .free_sta = rate_control_pid_free_sta,
-#ifdef CONFIG_MAC80211_DEBUGFS
- .add_sta_debugfs = rate_control_pid_add_sta_debugfs,
- .remove_sta_debugfs = rate_control_pid_remove_sta_debugfs,
-#endif
-};
-
-MODULE_DESCRIPTION("PID controller based rate control algorithm");
-MODULE_AUTHOR("Stefano Brivio");
-MODULE_AUTHOR("Mattias Nissler");
-MODULE_LICENSE("GPL");
-
-int __init rc80211_pid_init(void)
-{
- return ieee80211_rate_control_register(&mac80211_rcpid);
-}
-
-void rc80211_pid_exit(void)
-{
- ieee80211_rate_control_unregister(&mac80211_rcpid);
-}
-
-#ifdef CONFIG_MAC80211_RC_PID_MODULE
-module_init(rc80211_pid_init);
-module_exit(rc80211_pid_exit);
-#endif