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Mattias Nisslerad018372007-12-19 01:25:57 +01001/*
2 * Copyright 2002-2005, Instant802 Networks, Inc.
3 * Copyright 2005, Devicescape Software, Inc.
4 * Copyright 2007, Mattias Nissler <mattias.nissler@gmx.de>
Stefano Briviob7c50de92008-01-29 20:29:16 +01005 * Copyright 2007-2008, Stefano Brivio <stefano.brivio@polimi.it>
Mattias Nisslerad018372007-12-19 01:25:57 +01006 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11
12#include <linux/netdevice.h>
13#include <linux/types.h>
14#include <linux/skbuff.h>
Johannes Berg4b475892008-01-02 15:17:03 +010015#include <linux/debugfs.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090016#include <linux/slab.h>
Mattias Nisslerad018372007-12-19 01:25:57 +010017#include <net/mac80211.h>
Johannes Berg2c8dccc2008-04-08 15:14:40 -040018#include "rate.h"
Luis Carlos Coboee385852008-02-23 15:17:11 +010019#include "mesh.h"
Mattias Nissler12446c62007-12-19 01:27:18 +010020#include "rc80211_pid.h"
21
Mattias Nisslerad018372007-12-19 01:25:57 +010022
23/* This is an implementation of a TX rate control algorithm that uses a PID
24 * controller. Given a target failed frames rate, the controller decides about
25 * TX rate changes to meet the target failed frames rate.
26 *
27 * The controller basically computes the following:
28 *
Stefano Brivio1dc4d1e2007-12-19 01:26:52 +010029 * adj = CP * err + CI * err_avg + CD * (err - last_err) * (1 + sharpening)
Mattias Nisslerad018372007-12-19 01:25:57 +010030 *
31 * where
32 * adj adjustment value that is used to switch TX rate (see below)
33 * err current error: target vs. current failed frames percentage
34 * last_err last error
35 * err_avg average (i.e. poor man's integral) of recent errors
Stefano Brivio1dc4d1e2007-12-19 01:26:52 +010036 * sharpening non-zero when fast response is needed (i.e. right after
37 * association or no frames sent for a long time), heading
38 * to zero over time
Mattias Nisslerad018372007-12-19 01:25:57 +010039 * CP Proportional coefficient
40 * CI Integral coefficient
41 * CD Derivative coefficient
42 *
43 * CP, CI, CD are subject to careful tuning.
44 *
45 * The integral component uses a exponential moving average approach instead of
46 * an actual sliding window. The advantage is that we don't need to keep an
47 * array of the last N error values and computation is easier.
48 *
Stefano Brivio90d501d2007-12-19 01:26:34 +010049 * Once we have the adj value, we map it to a rate by means of a learning
50 * algorithm. This algorithm keeps the state of the percentual failed frames
51 * difference between rates. The behaviour of the lowest available rate is kept
52 * as a reference value, and every time we switch between two rates, we compute
53 * the difference between the failed frames each rate exhibited. By doing so,
54 * we compare behaviours which different rates exhibited in adjacent timeslices,
55 * thus the comparison is minimally affected by external conditions. This
56 * difference gets propagated to the whole set of measurements, so that the
57 * reference is always the same. Periodically, we normalize this set so that
58 * recent events weigh the most. By comparing the adj value with this set, we
59 * avoid pejorative switches to lower rates and allow for switches to higher
60 * rates if they behaved well.
Mattias Nisslerad018372007-12-19 01:25:57 +010061 *
62 * Note that for the computations we use a fixed-point representation to avoid
63 * floating point arithmetic. Hence, all values are shifted left by
64 * RC_PID_ARITH_SHIFT.
65 */
66
Mattias Nisslerad018372007-12-19 01:25:57 +010067
Stefano Briviob7c50de92008-01-29 20:29:16 +010068/* Adjust the rate while ensuring that we won't switch to a lower rate if it
69 * exhibited a worse failed frames behaviour and we'll choose the highest rate
70 * whose failed frames behaviour is not worse than the one of the original rate
71 * target. While at it, check that the new rate is valid. */
Johannes Berg4b7679a2008-09-18 18:14:18 +020072static void rate_control_pid_adjust_rate(struct ieee80211_supported_band *sband,
73 struct ieee80211_sta *sta,
74 struct rc_pid_sta_info *spinfo, int adj,
Stefano Brivio90d501d2007-12-19 01:26:34 +010075 struct rc_pid_rateinfo *rinfo)
Mattias Nisslerad018372007-12-19 01:25:57 +010076{
Stefano Briviob7c50de92008-01-29 20:29:16 +010077 int cur_sorted, new_sorted, probe, tmp, n_bitrates, band;
Johannes Bergae17e982008-09-11 03:04:36 +020078 int cur = spinfo->txrate_idx;
Mattias Nisslerad018372007-12-19 01:25:57 +010079
Stefano Briviob7c50de92008-01-29 20:29:16 +010080 band = sband->band;
81 n_bitrates = sband->n_bitrates;
Mattias Nisslerad018372007-12-19 01:25:57 +010082
Stefano Briviob7c50de92008-01-29 20:29:16 +010083 /* Map passed arguments to sorted values. */
84 cur_sorted = rinfo[cur].rev_index;
85 new_sorted = cur_sorted + adj;
Mattias Nisslerad018372007-12-19 01:25:57 +010086
Stefano Briviob7c50de92008-01-29 20:29:16 +010087 /* Check limits. */
88 if (new_sorted < 0)
89 new_sorted = rinfo[0].rev_index;
90 else if (new_sorted >= n_bitrates)
91 new_sorted = rinfo[n_bitrates - 1].rev_index;
92
93 tmp = new_sorted;
94
95 if (adj < 0) {
96 /* Ensure that the rate decrease isn't disadvantageous. */
97 for (probe = cur_sorted; probe >= new_sorted; probe--)
98 if (rinfo[probe].diff <= rinfo[cur_sorted].diff &&
99 rate_supported(sta, band, rinfo[probe].index))
100 tmp = probe;
101 } else {
102 /* Look for rate increase with zero (or below) cost. */
103 for (probe = new_sorted + 1; probe < n_bitrates; probe++)
104 if (rinfo[probe].diff <= rinfo[new_sorted].diff &&
105 rate_supported(sta, band, rinfo[probe].index))
106 tmp = probe;
107 }
108
109 /* Fit the rate found to the nearest supported rate. */
110 do {
111 if (rate_supported(sta, band, rinfo[tmp].index)) {
Johannes Bergae17e982008-09-11 03:04:36 +0200112 spinfo->txrate_idx = rinfo[tmp].index;
Mattias Nisslerad018372007-12-19 01:25:57 +0100113 break;
114 }
Stefano Briviob7c50de92008-01-29 20:29:16 +0100115 if (adj < 0)
116 tmp--;
117 else
118 tmp++;
119 } while (tmp < n_bitrates && tmp >= 0);
Mattias Nissler12446c62007-12-19 01:27:18 +0100120
121#ifdef CONFIG_MAC80211_DEBUGFS
Johannes Bergae17e982008-09-11 03:04:36 +0200122 rate_control_pid_event_rate_change(&spinfo->events,
123 spinfo->txrate_idx,
124 sband->bitrates[spinfo->txrate_idx].bitrate);
Mattias Nissler12446c62007-12-19 01:27:18 +0100125#endif
Mattias Nisslerad018372007-12-19 01:25:57 +0100126}
127
Stefano Brivio90d501d2007-12-19 01:26:34 +0100128/* Normalize the failed frames per-rate differences. */
Mattias Nissler1946b742007-12-20 13:27:26 +0100129static void rate_control_pid_normalize(struct rc_pid_info *pinfo, int l)
Stefano Brivio90d501d2007-12-19 01:26:34 +0100130{
Mattias Nissler1946b742007-12-20 13:27:26 +0100131 int i, norm_offset = pinfo->norm_offset;
132 struct rc_pid_rateinfo *r = pinfo->rinfo;
Stefano Brivio90d501d2007-12-19 01:26:34 +0100133
Mattias Nissler1946b742007-12-20 13:27:26 +0100134 if (r[0].diff > norm_offset)
135 r[0].diff -= norm_offset;
136 else if (r[0].diff < -norm_offset)
137 r[0].diff += norm_offset;
Stefano Brivio90d501d2007-12-19 01:26:34 +0100138 for (i = 0; i < l - 1; i++)
Mattias Nissler1946b742007-12-20 13:27:26 +0100139 if (r[i + 1].diff > r[i].diff + norm_offset)
140 r[i + 1].diff -= norm_offset;
Stefano Brivio90d501d2007-12-19 01:26:34 +0100141 else if (r[i + 1].diff <= r[i].diff)
Mattias Nissler1946b742007-12-20 13:27:26 +0100142 r[i + 1].diff += norm_offset;
Stefano Brivio90d501d2007-12-19 01:26:34 +0100143}
144
Mattias Nisslerad018372007-12-19 01:25:57 +0100145static void rate_control_pid_sample(struct rc_pid_info *pinfo,
Johannes Berg4b7679a2008-09-18 18:14:18 +0200146 struct ieee80211_supported_band *sband,
147 struct ieee80211_sta *sta,
148 struct rc_pid_sta_info *spinfo)
Mattias Nisslerad018372007-12-19 01:25:57 +0100149{
Stefano Brivio90d501d2007-12-19 01:26:34 +0100150 struct rc_pid_rateinfo *rinfo = pinfo->rinfo;
Mattias Nisslerad018372007-12-19 01:25:57 +0100151 u32 pf;
152 s32 err_avg;
Mattias Nissler1946b742007-12-20 13:27:26 +0100153 u32 err_prop;
154 u32 err_int;
155 u32 err_der;
Stefano Brivio90d501d2007-12-19 01:26:34 +0100156 int adj, i, j, tmp;
Mattias Nissler1946b742007-12-20 13:27:26 +0100157 unsigned long period;
Mattias Nisslerad018372007-12-19 01:25:57 +0100158
Stefano Brivio1dc4d1e2007-12-19 01:26:52 +0100159 /* In case nothing happened during the previous control interval, turn
160 * the sharpening factor on. */
Bob Copeland8e9310c2010-01-16 14:36:53 -0500161 period = msecs_to_jiffies(pinfo->sampling_period);
Mattias Nissler1946b742007-12-20 13:27:26 +0100162 if (jiffies - spinfo->last_sample > 2 * period)
163 spinfo->sharp_cnt = pinfo->sharpen_duration;
Stefano Brivio1dc4d1e2007-12-19 01:26:52 +0100164
Mattias Nisslerad018372007-12-19 01:25:57 +0100165 spinfo->last_sample = jiffies;
166
Stefano Brivio1dc4d1e2007-12-19 01:26:52 +0100167 /* This should never happen, but in case, we assume the old sample is
Mattias Nisslerad018372007-12-19 01:25:57 +0100168 * still a good measurement and copy it. */
Stefano Brivio1dc4d1e2007-12-19 01:26:52 +0100169 if (unlikely(spinfo->tx_num_xmit == 0))
Mattias Nisslerad018372007-12-19 01:25:57 +0100170 pf = spinfo->last_pf;
Javier Cardonabfc32e62009-08-17 17:15:55 -0700171 else
Mattias Nisslerad018372007-12-19 01:25:57 +0100172 pf = spinfo->tx_num_failed * 100 / spinfo->tx_num_xmit;
Johannes Berg4b7679a2008-09-18 18:14:18 +0200173
Stefano Brivio1dc4d1e2007-12-19 01:26:52 +0100174 spinfo->tx_num_xmit = 0;
175 spinfo->tx_num_failed = 0;
176
Stefano Brivio90d501d2007-12-19 01:26:34 +0100177 /* If we just switched rate, update the rate behaviour info. */
Johannes Bergae17e982008-09-11 03:04:36 +0200178 if (pinfo->oldrate != spinfo->txrate_idx) {
Stefano Brivio90d501d2007-12-19 01:26:34 +0100179
180 i = rinfo[pinfo->oldrate].rev_index;
Johannes Bergae17e982008-09-11 03:04:36 +0200181 j = rinfo[spinfo->txrate_idx].rev_index;
Stefano Brivio90d501d2007-12-19 01:26:34 +0100182
183 tmp = (pf - spinfo->last_pf);
184 tmp = RC_PID_DO_ARITH_RIGHT_SHIFT(tmp, RC_PID_ARITH_SHIFT);
185
186 rinfo[j].diff = rinfo[i].diff + tmp;
Johannes Bergae17e982008-09-11 03:04:36 +0200187 pinfo->oldrate = spinfo->txrate_idx;
Stefano Brivio90d501d2007-12-19 01:26:34 +0100188 }
Johannes Berg8318d782008-01-24 19:38:38 +0100189 rate_control_pid_normalize(pinfo, sband->n_bitrates);
Stefano Brivio90d501d2007-12-19 01:26:34 +0100190
Mattias Nisslerad018372007-12-19 01:25:57 +0100191 /* Compute the proportional, integral and derivative errors. */
Bob Copelande850f682010-01-16 14:36:52 -0500192 err_prop = (pinfo->target - pf) << RC_PID_ARITH_SHIFT;
Mattias Nisslerad018372007-12-19 01:25:57 +0100193
Mattias Nissler1946b742007-12-20 13:27:26 +0100194 err_avg = spinfo->err_avg_sc >> pinfo->smoothing_shift;
Mattias Nisslerad018372007-12-19 01:25:57 +0100195 spinfo->err_avg_sc = spinfo->err_avg_sc - err_avg + err_prop;
Mattias Nissler1946b742007-12-20 13:27:26 +0100196 err_int = spinfo->err_avg_sc >> pinfo->smoothing_shift;
Mattias Nisslerad018372007-12-19 01:25:57 +0100197
Mattias Nissler1946b742007-12-20 13:27:26 +0100198 err_der = (pf - spinfo->last_pf) *
199 (1 + pinfo->sharpen_factor * spinfo->sharp_cnt);
Mattias Nisslerad018372007-12-19 01:25:57 +0100200 spinfo->last_pf = pf;
Stefano Brivio1dc4d1e2007-12-19 01:26:52 +0100201 if (spinfo->sharp_cnt)
202 spinfo->sharp_cnt--;
Mattias Nisslerad018372007-12-19 01:25:57 +0100203
Mattias Nissler12446c62007-12-19 01:27:18 +0100204#ifdef CONFIG_MAC80211_DEBUGFS
205 rate_control_pid_event_pf_sample(&spinfo->events, pf, err_prop, err_int,
206 err_der);
207#endif
208
Mattias Nisslerad018372007-12-19 01:25:57 +0100209 /* Compute the controller output. */
210 adj = (err_prop * pinfo->coeff_p + err_int * pinfo->coeff_i
211 + err_der * pinfo->coeff_d);
Stefano Brivio90d501d2007-12-19 01:26:34 +0100212 adj = RC_PID_DO_ARITH_RIGHT_SHIFT(adj, 2 * RC_PID_ARITH_SHIFT);
Mattias Nisslerad018372007-12-19 01:25:57 +0100213
214 /* Change rate. */
215 if (adj)
Johannes Berg4b7679a2008-09-18 18:14:18 +0200216 rate_control_pid_adjust_rate(sband, sta, spinfo, adj, rinfo);
Mattias Nisslerad018372007-12-19 01:25:57 +0100217}
218
Johannes Berg4b7679a2008-09-18 18:14:18 +0200219static void rate_control_pid_tx_status(void *priv, struct ieee80211_supported_band *sband,
220 struct ieee80211_sta *sta, void *priv_sta,
Johannes Berge039fa42008-05-15 12:55:29 +0200221 struct sk_buff *skb)
Mattias Nisslerad018372007-12-19 01:25:57 +0100222{
Mattias Nisslerad018372007-12-19 01:25:57 +0100223 struct rc_pid_info *pinfo = priv;
Johannes Berg4b7679a2008-09-18 18:14:18 +0200224 struct rc_pid_sta_info *spinfo = priv_sta;
Mattias Nissler1946b742007-12-20 13:27:26 +0100225 unsigned long period;
Johannes Berge039fa42008-05-15 12:55:29 +0200226 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
Mattias Nisslerad018372007-12-19 01:25:57 +0100227
Johannes Berg4b7679a2008-09-18 18:14:18 +0200228 if (!spinfo)
229 return;
Andrew Lutomirskidf26e7e2008-01-03 21:05:37 -0800230
Mattias Nisslerad018372007-12-19 01:25:57 +0100231 /* Ignore all frames that were sent with a different rate than the rate
232 * we currently advise mac80211 to use. */
Johannes Berge6a98542008-10-21 12:40:02 +0200233 if (info->status.rates[0].idx != spinfo->txrate_idx)
Johannes Berg4b7679a2008-09-18 18:14:18 +0200234 return;
Mattias Nisslerad018372007-12-19 01:25:57 +0100235
Mattias Nisslerad018372007-12-19 01:25:57 +0100236 spinfo->tx_num_xmit++;
237
Mattias Nissler12446c62007-12-19 01:27:18 +0100238#ifdef CONFIG_MAC80211_DEBUGFS
Johannes Berge039fa42008-05-15 12:55:29 +0200239 rate_control_pid_event_tx_status(&spinfo->events, info);
Mattias Nissler12446c62007-12-19 01:27:18 +0100240#endif
241
Mattias Nisslerad018372007-12-19 01:25:57 +0100242 /* We count frames that totally failed to be transmitted as two bad
243 * frames, those that made it out but had some retries as one good and
244 * one bad frame. */
Johannes Berge6a98542008-10-21 12:40:02 +0200245 if (!(info->flags & IEEE80211_TX_STAT_ACK)) {
Mattias Nisslerad018372007-12-19 01:25:57 +0100246 spinfo->tx_num_failed += 2;
247 spinfo->tx_num_xmit++;
Larry Finger1dc5a842008-11-16 17:09:25 -0600248 } else if (info->status.rates[0].count > 1) {
Mattias Nisslerad018372007-12-19 01:25:57 +0100249 spinfo->tx_num_failed++;
250 spinfo->tx_num_xmit++;
251 }
252
Mattias Nisslerad018372007-12-19 01:25:57 +0100253 /* Update PID controller state. */
Bob Copeland8e9310c2010-01-16 14:36:53 -0500254 period = msecs_to_jiffies(pinfo->sampling_period);
Mattias Nissler1946b742007-12-20 13:27:26 +0100255 if (time_after(jiffies, spinfo->last_sample + period))
Johannes Berg4b7679a2008-09-18 18:14:18 +0200256 rate_control_pid_sample(pinfo, sband, sta, spinfo);
Mattias Nisslerad018372007-12-19 01:25:57 +0100257}
258
Johannes Berg4b7679a2008-09-18 18:14:18 +0200259static void
Johannes Berge6a98542008-10-21 12:40:02 +0200260rate_control_pid_get_rate(void *priv, struct ieee80211_sta *sta,
261 void *priv_sta,
262 struct ieee80211_tx_rate_control *txrc)
Mattias Nisslerad018372007-12-19 01:25:57 +0100263{
Johannes Berge6a98542008-10-21 12:40:02 +0200264 struct sk_buff *skb = txrc->skb;
265 struct ieee80211_supported_band *sband = txrc->sband;
Johannes Berge6a98542008-10-21 12:40:02 +0200266 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
Johannes Berg4b7679a2008-09-18 18:14:18 +0200267 struct rc_pid_sta_info *spinfo = priv_sta;
Mattias Nisslerad018372007-12-19 01:25:57 +0100268 int rateidx;
269
Johannes Berge6a98542008-10-21 12:40:02 +0200270 if (txrc->rts)
271 info->control.rates[0].count =
272 txrc->hw->conf.long_frame_max_tx_count;
273 else
274 info->control.rates[0].count =
275 txrc->hw->conf.short_frame_max_tx_count;
276
Gábor Stefanik92236842009-04-23 20:06:06 +0200277 /* Send management frames and NO_ACK data using lowest rate. */
Luis R. Rodriguez4c6d4f52009-07-16 10:05:41 -0700278 if (rate_control_send_low(sta, priv_sta, txrc))
Mattias Nisslerad018372007-12-19 01:25:57 +0100279 return;
Mattias Nisslerad018372007-12-19 01:25:57 +0100280
Johannes Bergae17e982008-09-11 03:04:36 +0200281 rateidx = spinfo->txrate_idx;
Mattias Nisslerad018372007-12-19 01:25:57 +0100282
Johannes Berg8318d782008-01-24 19:38:38 +0100283 if (rateidx >= sband->n_bitrates)
284 rateidx = sband->n_bitrates - 1;
Mattias Nisslerad018372007-12-19 01:25:57 +0100285
Johannes Berge6a98542008-10-21 12:40:02 +0200286 info->control.rates[0].idx = rateidx;
Mattias Nissler12446c62007-12-19 01:27:18 +0100287
288#ifdef CONFIG_MAC80211_DEBUGFS
Johannes Berg4b7679a2008-09-18 18:14:18 +0200289 rate_control_pid_event_tx_rate(&spinfo->events,
Johannes Berg8318d782008-01-24 19:38:38 +0100290 rateidx, sband->bitrates[rateidx].bitrate);
Mattias Nissler12446c62007-12-19 01:27:18 +0100291#endif
Mattias Nisslerad018372007-12-19 01:25:57 +0100292}
293
Johannes Berg4b7679a2008-09-18 18:14:18 +0200294static void
295rate_control_pid_rate_init(void *priv, struct ieee80211_supported_band *sband,
Simon Wunderlich3de805c2013-07-08 16:55:50 +0200296 struct cfg80211_chan_def *chandef,
Johannes Berg4b7679a2008-09-18 18:14:18 +0200297 struct ieee80211_sta *sta, void *priv_sta)
Mattias Nisslerad018372007-12-19 01:25:57 +0100298{
Johannes Berg4b7679a2008-09-18 18:14:18 +0200299 struct rc_pid_sta_info *spinfo = priv_sta;
Jiri Slaby69092682009-05-04 18:10:28 +0200300 struct rc_pid_info *pinfo = priv;
301 struct rc_pid_rateinfo *rinfo = pinfo->rinfo;
Jiri Slaby69092682009-05-04 18:10:28 +0200302 int i, j, tmp;
303 bool s;
Johannes Berg4b7679a2008-09-18 18:14:18 +0200304
Mattias Nisslerad018372007-12-19 01:25:57 +0100305 /* TODO: This routine should consider using RSSI from previous packets
306 * as we need to have IEEE 802.1X auth succeed immediately after assoc..
307 * Until that method is implemented, we will use the lowest supported
308 * rate as a workaround. */
Johannes Berg8318d782008-01-24 19:38:38 +0100309
Stefano Brivio90d501d2007-12-19 01:26:34 +0100310 /* Sort the rates. This is optimized for the most common case (i.e.
311 * almost-sorted CCK+OFDM rates). Kind of bubble-sort with reversed
312 * mapping too. */
Johannes Berg8318d782008-01-24 19:38:38 +0100313 for (i = 0; i < sband->n_bitrates; i++) {
Stefano Brivio90d501d2007-12-19 01:26:34 +0100314 rinfo[i].index = i;
315 rinfo[i].rev_index = i;
Mattias Nissleradeed482008-07-07 23:08:19 +0200316 if (RC_PID_FAST_START)
Stefano Brivio90d501d2007-12-19 01:26:34 +0100317 rinfo[i].diff = 0;
318 else
Mattias Nissler1946b742007-12-20 13:27:26 +0100319 rinfo[i].diff = i * pinfo->norm_offset;
Stefano Brivio90d501d2007-12-19 01:26:34 +0100320 }
Johannes Berg8318d782008-01-24 19:38:38 +0100321 for (i = 1; i < sband->n_bitrates; i++) {
Rusty Russell3db1cd52011-12-19 13:56:45 +0000322 s = false;
Johannes Berg8318d782008-01-24 19:38:38 +0100323 for (j = 0; j < sband->n_bitrates - i; j++)
324 if (unlikely(sband->bitrates[rinfo[j].index].bitrate >
325 sband->bitrates[rinfo[j + 1].index].bitrate)) {
Stefano Brivio90d501d2007-12-19 01:26:34 +0100326 tmp = rinfo[j].index;
327 rinfo[j].index = rinfo[j + 1].index;
328 rinfo[j + 1].index = tmp;
329 rinfo[rinfo[j].index].rev_index = j;
330 rinfo[rinfo[j + 1].index].rev_index = j + 1;
Rusty Russell3db1cd52011-12-19 13:56:45 +0000331 s = true;
Stefano Brivio90d501d2007-12-19 01:26:34 +0100332 }
333 if (!s)
334 break;
335 }
Mattias Nisslerad018372007-12-19 01:25:57 +0100336
Jiri Slaby69092682009-05-04 18:10:28 +0200337 spinfo->txrate_idx = rate_lowest_index(sband, sta);
Jiri Slaby69092682009-05-04 18:10:28 +0200338}
339
340static void *rate_control_pid_alloc(struct ieee80211_hw *hw,
341 struct dentry *debugfsdir)
342{
343 struct rc_pid_info *pinfo;
344 struct rc_pid_rateinfo *rinfo;
345 struct ieee80211_supported_band *sband;
346 int i, max_rates = 0;
347#ifdef CONFIG_MAC80211_DEBUGFS
348 struct rc_pid_debugfs_entries *de;
349#endif
350
351 pinfo = kmalloc(sizeof(*pinfo), GFP_ATOMIC);
352 if (!pinfo)
353 return NULL;
354
355 for (i = 0; i < IEEE80211_NUM_BANDS; i++) {
356 sband = hw->wiphy->bands[i];
John W. Linville621ad7c2009-05-05 15:18:26 -0400357 if (sband && sband->n_bitrates > max_rates)
Jiri Slaby69092682009-05-04 18:10:28 +0200358 max_rates = sband->n_bitrates;
359 }
360
361 rinfo = kmalloc(sizeof(*rinfo) * max_rates, GFP_ATOMIC);
362 if (!rinfo) {
363 kfree(pinfo);
364 return NULL;
365 }
366
367 pinfo->target = RC_PID_TARGET_PF;
368 pinfo->sampling_period = RC_PID_INTERVAL;
369 pinfo->coeff_p = RC_PID_COEFF_P;
370 pinfo->coeff_i = RC_PID_COEFF_I;
371 pinfo->coeff_d = RC_PID_COEFF_D;
372 pinfo->smoothing_shift = RC_PID_SMOOTHING_SHIFT;
373 pinfo->sharpen_factor = RC_PID_SHARPENING_FACTOR;
374 pinfo->sharpen_duration = RC_PID_SHARPENING_DURATION;
375 pinfo->norm_offset = RC_PID_NORM_OFFSET;
376 pinfo->rinfo = rinfo;
377 pinfo->oldrate = 0;
378
Mattias Nissler1946b742007-12-20 13:27:26 +0100379#ifdef CONFIG_MAC80211_DEBUGFS
380 de = &pinfo->dentries;
Mattias Nissler1946b742007-12-20 13:27:26 +0100381 de->target = debugfs_create_u32("target_pf", S_IRUSR | S_IWUSR,
Johannes Berg4b7679a2008-09-18 18:14:18 +0200382 debugfsdir, &pinfo->target);
Mattias Nissler1946b742007-12-20 13:27:26 +0100383 de->sampling_period = debugfs_create_u32("sampling_period",
Johannes Berg4b7679a2008-09-18 18:14:18 +0200384 S_IRUSR | S_IWUSR, debugfsdir,
Mattias Nissler1946b742007-12-20 13:27:26 +0100385 &pinfo->sampling_period);
386 de->coeff_p = debugfs_create_u32("coeff_p", S_IRUSR | S_IWUSR,
Tomas Winkler9902b182008-11-08 23:50:55 +0200387 debugfsdir, (u32 *)&pinfo->coeff_p);
Mattias Nissler1946b742007-12-20 13:27:26 +0100388 de->coeff_i = debugfs_create_u32("coeff_i", S_IRUSR | S_IWUSR,
Tomas Winkler9902b182008-11-08 23:50:55 +0200389 debugfsdir, (u32 *)&pinfo->coeff_i);
Mattias Nissler1946b742007-12-20 13:27:26 +0100390 de->coeff_d = debugfs_create_u32("coeff_d", S_IRUSR | S_IWUSR,
Tomas Winkler9902b182008-11-08 23:50:55 +0200391 debugfsdir, (u32 *)&pinfo->coeff_d);
Mattias Nissler1946b742007-12-20 13:27:26 +0100392 de->smoothing_shift = debugfs_create_u32("smoothing_shift",
Johannes Berg4b7679a2008-09-18 18:14:18 +0200393 S_IRUSR | S_IWUSR, debugfsdir,
Mattias Nissler1946b742007-12-20 13:27:26 +0100394 &pinfo->smoothing_shift);
395 de->sharpen_factor = debugfs_create_u32("sharpen_factor",
Johannes Berg4b7679a2008-09-18 18:14:18 +0200396 S_IRUSR | S_IWUSR, debugfsdir,
Mattias Nissler1946b742007-12-20 13:27:26 +0100397 &pinfo->sharpen_factor);
398 de->sharpen_duration = debugfs_create_u32("sharpen_duration",
Johannes Berg4b7679a2008-09-18 18:14:18 +0200399 S_IRUSR | S_IWUSR, debugfsdir,
Mattias Nissler1946b742007-12-20 13:27:26 +0100400 &pinfo->sharpen_duration);
401 de->norm_offset = debugfs_create_u32("norm_offset",
Johannes Berg4b7679a2008-09-18 18:14:18 +0200402 S_IRUSR | S_IWUSR, debugfsdir,
Mattias Nissler1946b742007-12-20 13:27:26 +0100403 &pinfo->norm_offset);
Mattias Nissler1946b742007-12-20 13:27:26 +0100404#endif
405
Mattias Nisslerad018372007-12-19 01:25:57 +0100406 return pinfo;
407}
408
409static void rate_control_pid_free(void *priv)
410{
411 struct rc_pid_info *pinfo = priv;
Mattias Nissler1946b742007-12-20 13:27:26 +0100412#ifdef CONFIG_MAC80211_DEBUGFS
413 struct rc_pid_debugfs_entries *de = &pinfo->dentries;
414
Mattias Nissler1946b742007-12-20 13:27:26 +0100415 debugfs_remove(de->norm_offset);
416 debugfs_remove(de->sharpen_duration);
417 debugfs_remove(de->sharpen_factor);
418 debugfs_remove(de->smoothing_shift);
419 debugfs_remove(de->coeff_d);
420 debugfs_remove(de->coeff_i);
421 debugfs_remove(de->coeff_p);
422 debugfs_remove(de->sampling_period);
423 debugfs_remove(de->target);
Mattias Nissler1946b742007-12-20 13:27:26 +0100424#endif
425
Stefano Brivio90d501d2007-12-19 01:26:34 +0100426 kfree(pinfo->rinfo);
Mattias Nisslerad018372007-12-19 01:25:57 +0100427 kfree(pinfo);
428}
429
Johannes Berg4b7679a2008-09-18 18:14:18 +0200430static void *rate_control_pid_alloc_sta(void *priv, struct ieee80211_sta *sta,
431 gfp_t gfp)
Mattias Nisslerad018372007-12-19 01:25:57 +0100432{
433 struct rc_pid_sta_info *spinfo;
434
435 spinfo = kzalloc(sizeof(*spinfo), gfp);
Mattias Nissler12446c62007-12-19 01:27:18 +0100436 if (spinfo == NULL)
437 return NULL;
438
Stefano Brivioc09c7232008-01-17 00:38:29 +0100439 spinfo->last_sample = jiffies;
440
Mattias Nissler12446c62007-12-19 01:27:18 +0100441#ifdef CONFIG_MAC80211_DEBUGFS
442 spin_lock_init(&spinfo->events.lock);
443 init_waitqueue_head(&spinfo->events.waitqueue);
444#endif
Mattias Nisslerad018372007-12-19 01:25:57 +0100445
446 return spinfo;
447}
448
Johannes Berg4b7679a2008-09-18 18:14:18 +0200449static void rate_control_pid_free_sta(void *priv, struct ieee80211_sta *sta,
450 void *priv_sta)
Mattias Nisslerad018372007-12-19 01:25:57 +0100451{
Johannes Berg4b7679a2008-09-18 18:14:18 +0200452 kfree(priv_sta);
Mattias Nisslerad018372007-12-19 01:25:57 +0100453}
454
Johannes Berg4b475892008-01-02 15:17:03 +0100455static struct rate_control_ops mac80211_rcpid = {
Mattias Nisslerad018372007-12-19 01:25:57 +0100456 .name = "pid",
457 .tx_status = rate_control_pid_tx_status,
458 .get_rate = rate_control_pid_get_rate,
459 .rate_init = rate_control_pid_rate_init,
Mattias Nisslerad018372007-12-19 01:25:57 +0100460 .alloc = rate_control_pid_alloc,
461 .free = rate_control_pid_free,
462 .alloc_sta = rate_control_pid_alloc_sta,
463 .free_sta = rate_control_pid_free_sta,
Mattias Nissler12446c62007-12-19 01:27:18 +0100464#ifdef CONFIG_MAC80211_DEBUGFS
465 .add_sta_debugfs = rate_control_pid_add_sta_debugfs,
466 .remove_sta_debugfs = rate_control_pid_remove_sta_debugfs,
467#endif
Mattias Nisslerad018372007-12-19 01:25:57 +0100468};
Johannes Berg4b475892008-01-02 15:17:03 +0100469
Johannes Berg4b475892008-01-02 15:17:03 +0100470int __init rc80211_pid_init(void)
471{
472 return ieee80211_rate_control_register(&mac80211_rcpid);
473}
474
Johannes Bergf0b92052008-01-31 19:31:57 +0100475void rc80211_pid_exit(void)
Johannes Berg4b475892008-01-02 15:17:03 +0100476{
477 ieee80211_rate_control_unregister(&mac80211_rcpid);
478}