Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2002-2005, Instant802 Networks, Inc. |
| 3 | * Copyright 2005, Devicescape Software, Inc. |
| 4 | * Copyright 2007, Mattias Nissler <mattias.nissler@gmx.de> |
Stefano Brivio | b7c50de9 | 2008-01-29 20:29:16 +0100 | [diff] [blame] | 5 | * Copyright 2007-2008, Stefano Brivio <stefano.brivio@polimi.it> |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 6 | * |
| 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 Berg | 4b47589 | 2008-01-02 15:17:03 +0100 | [diff] [blame] | 15 | #include <linux/debugfs.h> |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 16 | #include <net/mac80211.h> |
Johannes Berg | 2c8dccc | 2008-04-08 15:14:40 -0400 | [diff] [blame] | 17 | #include "rate.h" |
Luis Carlos Cobo | ee38585 | 2008-02-23 15:17:11 +0100 | [diff] [blame] | 18 | #include "mesh.h" |
Mattias Nissler | 12446c6 | 2007-12-19 01:27:18 +0100 | [diff] [blame] | 19 | #include "rc80211_pid.h" |
| 20 | |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 21 | |
| 22 | /* This is an implementation of a TX rate control algorithm that uses a PID |
| 23 | * controller. Given a target failed frames rate, the controller decides about |
| 24 | * TX rate changes to meet the target failed frames rate. |
| 25 | * |
| 26 | * The controller basically computes the following: |
| 27 | * |
Stefano Brivio | 1dc4d1e | 2007-12-19 01:26:52 +0100 | [diff] [blame] | 28 | * adj = CP * err + CI * err_avg + CD * (err - last_err) * (1 + sharpening) |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 29 | * |
| 30 | * where |
| 31 | * adj adjustment value that is used to switch TX rate (see below) |
| 32 | * err current error: target vs. current failed frames percentage |
| 33 | * last_err last error |
| 34 | * err_avg average (i.e. poor man's integral) of recent errors |
Stefano Brivio | 1dc4d1e | 2007-12-19 01:26:52 +0100 | [diff] [blame] | 35 | * sharpening non-zero when fast response is needed (i.e. right after |
| 36 | * association or no frames sent for a long time), heading |
| 37 | * to zero over time |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 38 | * CP Proportional coefficient |
| 39 | * CI Integral coefficient |
| 40 | * CD Derivative coefficient |
| 41 | * |
| 42 | * CP, CI, CD are subject to careful tuning. |
| 43 | * |
| 44 | * The integral component uses a exponential moving average approach instead of |
| 45 | * an actual sliding window. The advantage is that we don't need to keep an |
| 46 | * array of the last N error values and computation is easier. |
| 47 | * |
Stefano Brivio | 90d501d | 2007-12-19 01:26:34 +0100 | [diff] [blame] | 48 | * Once we have the adj value, we map it to a rate by means of a learning |
| 49 | * algorithm. This algorithm keeps the state of the percentual failed frames |
| 50 | * difference between rates. The behaviour of the lowest available rate is kept |
| 51 | * as a reference value, and every time we switch between two rates, we compute |
| 52 | * the difference between the failed frames each rate exhibited. By doing so, |
| 53 | * we compare behaviours which different rates exhibited in adjacent timeslices, |
| 54 | * thus the comparison is minimally affected by external conditions. This |
| 55 | * difference gets propagated to the whole set of measurements, so that the |
| 56 | * reference is always the same. Periodically, we normalize this set so that |
| 57 | * recent events weigh the most. By comparing the adj value with this set, we |
| 58 | * avoid pejorative switches to lower rates and allow for switches to higher |
| 59 | * rates if they behaved well. |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 60 | * |
| 61 | * Note that for the computations we use a fixed-point representation to avoid |
| 62 | * floating point arithmetic. Hence, all values are shifted left by |
| 63 | * RC_PID_ARITH_SHIFT. |
| 64 | */ |
| 65 | |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 66 | |
Stefano Brivio | b7c50de9 | 2008-01-29 20:29:16 +0100 | [diff] [blame] | 67 | /* Adjust the rate while ensuring that we won't switch to a lower rate if it |
| 68 | * exhibited a worse failed frames behaviour and we'll choose the highest rate |
| 69 | * whose failed frames behaviour is not worse than the one of the original rate |
| 70 | * target. While at it, check that the new rate is valid. */ |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 71 | static void rate_control_pid_adjust_rate(struct ieee80211_supported_band *sband, |
| 72 | struct ieee80211_sta *sta, |
| 73 | struct rc_pid_sta_info *spinfo, int adj, |
Stefano Brivio | 90d501d | 2007-12-19 01:26:34 +0100 | [diff] [blame] | 74 | struct rc_pid_rateinfo *rinfo) |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 75 | { |
Stefano Brivio | b7c50de9 | 2008-01-29 20:29:16 +0100 | [diff] [blame] | 76 | int cur_sorted, new_sorted, probe, tmp, n_bitrates, band; |
Johannes Berg | ae17e98 | 2008-09-11 03:04:36 +0200 | [diff] [blame] | 77 | int cur = spinfo->txrate_idx; |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 78 | |
Stefano Brivio | b7c50de9 | 2008-01-29 20:29:16 +0100 | [diff] [blame] | 79 | band = sband->band; |
| 80 | n_bitrates = sband->n_bitrates; |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 81 | |
Stefano Brivio | b7c50de9 | 2008-01-29 20:29:16 +0100 | [diff] [blame] | 82 | /* Map passed arguments to sorted values. */ |
| 83 | cur_sorted = rinfo[cur].rev_index; |
| 84 | new_sorted = cur_sorted + adj; |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 85 | |
Stefano Brivio | b7c50de9 | 2008-01-29 20:29:16 +0100 | [diff] [blame] | 86 | /* Check limits. */ |
| 87 | if (new_sorted < 0) |
| 88 | new_sorted = rinfo[0].rev_index; |
| 89 | else if (new_sorted >= n_bitrates) |
| 90 | new_sorted = rinfo[n_bitrates - 1].rev_index; |
| 91 | |
| 92 | tmp = new_sorted; |
| 93 | |
| 94 | if (adj < 0) { |
| 95 | /* Ensure that the rate decrease isn't disadvantageous. */ |
| 96 | for (probe = cur_sorted; probe >= new_sorted; probe--) |
| 97 | if (rinfo[probe].diff <= rinfo[cur_sorted].diff && |
| 98 | rate_supported(sta, band, rinfo[probe].index)) |
| 99 | tmp = probe; |
| 100 | } else { |
| 101 | /* Look for rate increase with zero (or below) cost. */ |
| 102 | for (probe = new_sorted + 1; probe < n_bitrates; probe++) |
| 103 | if (rinfo[probe].diff <= rinfo[new_sorted].diff && |
| 104 | rate_supported(sta, band, rinfo[probe].index)) |
| 105 | tmp = probe; |
| 106 | } |
| 107 | |
| 108 | /* Fit the rate found to the nearest supported rate. */ |
| 109 | do { |
| 110 | if (rate_supported(sta, band, rinfo[tmp].index)) { |
Johannes Berg | ae17e98 | 2008-09-11 03:04:36 +0200 | [diff] [blame] | 111 | spinfo->txrate_idx = rinfo[tmp].index; |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 112 | break; |
| 113 | } |
Stefano Brivio | b7c50de9 | 2008-01-29 20:29:16 +0100 | [diff] [blame] | 114 | if (adj < 0) |
| 115 | tmp--; |
| 116 | else |
| 117 | tmp++; |
| 118 | } while (tmp < n_bitrates && tmp >= 0); |
Mattias Nissler | 12446c6 | 2007-12-19 01:27:18 +0100 | [diff] [blame] | 119 | |
| 120 | #ifdef CONFIG_MAC80211_DEBUGFS |
Johannes Berg | ae17e98 | 2008-09-11 03:04:36 +0200 | [diff] [blame] | 121 | rate_control_pid_event_rate_change(&spinfo->events, |
| 122 | spinfo->txrate_idx, |
| 123 | sband->bitrates[spinfo->txrate_idx].bitrate); |
Mattias Nissler | 12446c6 | 2007-12-19 01:27:18 +0100 | [diff] [blame] | 124 | #endif |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 125 | } |
| 126 | |
Stefano Brivio | 90d501d | 2007-12-19 01:26:34 +0100 | [diff] [blame] | 127 | /* Normalize the failed frames per-rate differences. */ |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 128 | static void rate_control_pid_normalize(struct rc_pid_info *pinfo, int l) |
Stefano Brivio | 90d501d | 2007-12-19 01:26:34 +0100 | [diff] [blame] | 129 | { |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 130 | int i, norm_offset = pinfo->norm_offset; |
| 131 | struct rc_pid_rateinfo *r = pinfo->rinfo; |
Stefano Brivio | 90d501d | 2007-12-19 01:26:34 +0100 | [diff] [blame] | 132 | |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 133 | if (r[0].diff > norm_offset) |
| 134 | r[0].diff -= norm_offset; |
| 135 | else if (r[0].diff < -norm_offset) |
| 136 | r[0].diff += norm_offset; |
Stefano Brivio | 90d501d | 2007-12-19 01:26:34 +0100 | [diff] [blame] | 137 | for (i = 0; i < l - 1; i++) |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 138 | if (r[i + 1].diff > r[i].diff + norm_offset) |
| 139 | r[i + 1].diff -= norm_offset; |
Stefano Brivio | 90d501d | 2007-12-19 01:26:34 +0100 | [diff] [blame] | 140 | else if (r[i + 1].diff <= r[i].diff) |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 141 | r[i + 1].diff += norm_offset; |
Stefano Brivio | 90d501d | 2007-12-19 01:26:34 +0100 | [diff] [blame] | 142 | } |
| 143 | |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 144 | static void rate_control_pid_sample(struct rc_pid_info *pinfo, |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 145 | struct ieee80211_supported_band *sband, |
| 146 | struct ieee80211_sta *sta, |
| 147 | struct rc_pid_sta_info *spinfo) |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 148 | { |
Stefano Brivio | 90d501d | 2007-12-19 01:26:34 +0100 | [diff] [blame] | 149 | struct rc_pid_rateinfo *rinfo = pinfo->rinfo; |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 150 | u32 pf; |
| 151 | s32 err_avg; |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 152 | u32 err_prop; |
| 153 | u32 err_int; |
| 154 | u32 err_der; |
Stefano Brivio | 90d501d | 2007-12-19 01:26:34 +0100 | [diff] [blame] | 155 | int adj, i, j, tmp; |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 156 | unsigned long period; |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 157 | |
Stefano Brivio | 1dc4d1e | 2007-12-19 01:26:52 +0100 | [diff] [blame] | 158 | /* In case nothing happened during the previous control interval, turn |
| 159 | * the sharpening factor on. */ |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 160 | period = (HZ * pinfo->sampling_period + 500) / 1000; |
| 161 | if (!period) |
| 162 | period = 1; |
| 163 | if (jiffies - spinfo->last_sample > 2 * period) |
| 164 | spinfo->sharp_cnt = pinfo->sharpen_duration; |
Stefano Brivio | 1dc4d1e | 2007-12-19 01:26:52 +0100 | [diff] [blame] | 165 | |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 166 | spinfo->last_sample = jiffies; |
| 167 | |
Stefano Brivio | 1dc4d1e | 2007-12-19 01:26:52 +0100 | [diff] [blame] | 168 | /* This should never happen, but in case, we assume the old sample is |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 169 | * still a good measurement and copy it. */ |
Stefano Brivio | 1dc4d1e | 2007-12-19 01:26:52 +0100 | [diff] [blame] | 170 | if (unlikely(spinfo->tx_num_xmit == 0)) |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 171 | pf = spinfo->last_pf; |
Javier Cardona | bfc32e6 | 2009-08-17 17:15:55 -0700 | [diff] [blame] | 172 | else |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 173 | pf = spinfo->tx_num_failed * 100 / spinfo->tx_num_xmit; |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 174 | |
Stefano Brivio | 1dc4d1e | 2007-12-19 01:26:52 +0100 | [diff] [blame] | 175 | spinfo->tx_num_xmit = 0; |
| 176 | spinfo->tx_num_failed = 0; |
| 177 | |
Stefano Brivio | 90d501d | 2007-12-19 01:26:34 +0100 | [diff] [blame] | 178 | /* If we just switched rate, update the rate behaviour info. */ |
Johannes Berg | ae17e98 | 2008-09-11 03:04:36 +0200 | [diff] [blame] | 179 | if (pinfo->oldrate != spinfo->txrate_idx) { |
Stefano Brivio | 90d501d | 2007-12-19 01:26:34 +0100 | [diff] [blame] | 180 | |
| 181 | i = rinfo[pinfo->oldrate].rev_index; |
Johannes Berg | ae17e98 | 2008-09-11 03:04:36 +0200 | [diff] [blame] | 182 | j = rinfo[spinfo->txrate_idx].rev_index; |
Stefano Brivio | 90d501d | 2007-12-19 01:26:34 +0100 | [diff] [blame] | 183 | |
| 184 | tmp = (pf - spinfo->last_pf); |
| 185 | tmp = RC_PID_DO_ARITH_RIGHT_SHIFT(tmp, RC_PID_ARITH_SHIFT); |
| 186 | |
| 187 | rinfo[j].diff = rinfo[i].diff + tmp; |
Johannes Berg | ae17e98 | 2008-09-11 03:04:36 +0200 | [diff] [blame] | 188 | pinfo->oldrate = spinfo->txrate_idx; |
Stefano Brivio | 90d501d | 2007-12-19 01:26:34 +0100 | [diff] [blame] | 189 | } |
Johannes Berg | 8318d78 | 2008-01-24 19:38:38 +0100 | [diff] [blame] | 190 | rate_control_pid_normalize(pinfo, sband->n_bitrates); |
Stefano Brivio | 90d501d | 2007-12-19 01:26:34 +0100 | [diff] [blame] | 191 | |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 192 | /* Compute the proportional, integral and derivative errors. */ |
Bob Copeland | e850f68 | 2010-01-16 14:36:52 -0500 | [diff] [blame^] | 193 | err_prop = (pinfo->target - pf) << RC_PID_ARITH_SHIFT; |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 194 | |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 195 | err_avg = spinfo->err_avg_sc >> pinfo->smoothing_shift; |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 196 | spinfo->err_avg_sc = spinfo->err_avg_sc - err_avg + err_prop; |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 197 | err_int = spinfo->err_avg_sc >> pinfo->smoothing_shift; |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 198 | |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 199 | err_der = (pf - spinfo->last_pf) * |
| 200 | (1 + pinfo->sharpen_factor * spinfo->sharp_cnt); |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 201 | spinfo->last_pf = pf; |
Stefano Brivio | 1dc4d1e | 2007-12-19 01:26:52 +0100 | [diff] [blame] | 202 | if (spinfo->sharp_cnt) |
| 203 | spinfo->sharp_cnt--; |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 204 | |
Mattias Nissler | 12446c6 | 2007-12-19 01:27:18 +0100 | [diff] [blame] | 205 | #ifdef CONFIG_MAC80211_DEBUGFS |
| 206 | rate_control_pid_event_pf_sample(&spinfo->events, pf, err_prop, err_int, |
| 207 | err_der); |
| 208 | #endif |
| 209 | |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 210 | /* Compute the controller output. */ |
| 211 | adj = (err_prop * pinfo->coeff_p + err_int * pinfo->coeff_i |
| 212 | + err_der * pinfo->coeff_d); |
Stefano Brivio | 90d501d | 2007-12-19 01:26:34 +0100 | [diff] [blame] | 213 | adj = RC_PID_DO_ARITH_RIGHT_SHIFT(adj, 2 * RC_PID_ARITH_SHIFT); |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 214 | |
| 215 | /* Change rate. */ |
| 216 | if (adj) |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 217 | rate_control_pid_adjust_rate(sband, sta, spinfo, adj, rinfo); |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 218 | } |
| 219 | |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 220 | static void rate_control_pid_tx_status(void *priv, struct ieee80211_supported_band *sband, |
| 221 | struct ieee80211_sta *sta, void *priv_sta, |
Johannes Berg | e039fa4 | 2008-05-15 12:55:29 +0200 | [diff] [blame] | 222 | struct sk_buff *skb) |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 223 | { |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 224 | struct rc_pid_info *pinfo = priv; |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 225 | struct rc_pid_sta_info *spinfo = priv_sta; |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 226 | unsigned long period; |
Johannes Berg | e039fa4 | 2008-05-15 12:55:29 +0200 | [diff] [blame] | 227 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 228 | |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 229 | if (!spinfo) |
| 230 | return; |
Andrew Lutomirski | df26e7e | 2008-01-03 21:05:37 -0800 | [diff] [blame] | 231 | |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 232 | /* Ignore all frames that were sent with a different rate than the rate |
| 233 | * we currently advise mac80211 to use. */ |
Johannes Berg | e6a9854 | 2008-10-21 12:40:02 +0200 | [diff] [blame] | 234 | if (info->status.rates[0].idx != spinfo->txrate_idx) |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 235 | return; |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 236 | |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 237 | spinfo->tx_num_xmit++; |
| 238 | |
Mattias Nissler | 12446c6 | 2007-12-19 01:27:18 +0100 | [diff] [blame] | 239 | #ifdef CONFIG_MAC80211_DEBUGFS |
Johannes Berg | e039fa4 | 2008-05-15 12:55:29 +0200 | [diff] [blame] | 240 | rate_control_pid_event_tx_status(&spinfo->events, info); |
Mattias Nissler | 12446c6 | 2007-12-19 01:27:18 +0100 | [diff] [blame] | 241 | #endif |
| 242 | |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 243 | /* We count frames that totally failed to be transmitted as two bad |
| 244 | * frames, those that made it out but had some retries as one good and |
| 245 | * one bad frame. */ |
Johannes Berg | e6a9854 | 2008-10-21 12:40:02 +0200 | [diff] [blame] | 246 | if (!(info->flags & IEEE80211_TX_STAT_ACK)) { |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 247 | spinfo->tx_num_failed += 2; |
| 248 | spinfo->tx_num_xmit++; |
Larry Finger | 1dc5a84 | 2008-11-16 17:09:25 -0600 | [diff] [blame] | 249 | } else if (info->status.rates[0].count > 1) { |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 250 | spinfo->tx_num_failed++; |
| 251 | spinfo->tx_num_xmit++; |
| 252 | } |
| 253 | |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 254 | /* Update PID controller state. */ |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 255 | period = (HZ * pinfo->sampling_period + 500) / 1000; |
| 256 | if (!period) |
| 257 | period = 1; |
| 258 | if (time_after(jiffies, spinfo->last_sample + period)) |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 259 | rate_control_pid_sample(pinfo, sband, sta, spinfo); |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 260 | } |
| 261 | |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 262 | static void |
Johannes Berg | e6a9854 | 2008-10-21 12:40:02 +0200 | [diff] [blame] | 263 | rate_control_pid_get_rate(void *priv, struct ieee80211_sta *sta, |
| 264 | void *priv_sta, |
| 265 | struct ieee80211_tx_rate_control *txrc) |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 266 | { |
Johannes Berg | e6a9854 | 2008-10-21 12:40:02 +0200 | [diff] [blame] | 267 | struct sk_buff *skb = txrc->skb; |
| 268 | struct ieee80211_supported_band *sband = txrc->sband; |
Johannes Berg | e6a9854 | 2008-10-21 12:40:02 +0200 | [diff] [blame] | 269 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 270 | struct rc_pid_sta_info *spinfo = priv_sta; |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 271 | int rateidx; |
| 272 | |
Johannes Berg | e6a9854 | 2008-10-21 12:40:02 +0200 | [diff] [blame] | 273 | if (txrc->rts) |
| 274 | info->control.rates[0].count = |
| 275 | txrc->hw->conf.long_frame_max_tx_count; |
| 276 | else |
| 277 | info->control.rates[0].count = |
| 278 | txrc->hw->conf.short_frame_max_tx_count; |
| 279 | |
Gábor Stefanik | 9223684 | 2009-04-23 20:06:06 +0200 | [diff] [blame] | 280 | /* Send management frames and NO_ACK data using lowest rate. */ |
Luis R. Rodriguez | 4c6d4f5 | 2009-07-16 10:05:41 -0700 | [diff] [blame] | 281 | if (rate_control_send_low(sta, priv_sta, txrc)) |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 282 | return; |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 283 | |
Johannes Berg | ae17e98 | 2008-09-11 03:04:36 +0200 | [diff] [blame] | 284 | rateidx = spinfo->txrate_idx; |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 285 | |
Johannes Berg | 8318d78 | 2008-01-24 19:38:38 +0100 | [diff] [blame] | 286 | if (rateidx >= sband->n_bitrates) |
| 287 | rateidx = sband->n_bitrates - 1; |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 288 | |
Johannes Berg | e6a9854 | 2008-10-21 12:40:02 +0200 | [diff] [blame] | 289 | info->control.rates[0].idx = rateidx; |
Mattias Nissler | 12446c6 | 2007-12-19 01:27:18 +0100 | [diff] [blame] | 290 | |
| 291 | #ifdef CONFIG_MAC80211_DEBUGFS |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 292 | rate_control_pid_event_tx_rate(&spinfo->events, |
Johannes Berg | 8318d78 | 2008-01-24 19:38:38 +0100 | [diff] [blame] | 293 | rateidx, sband->bitrates[rateidx].bitrate); |
Mattias Nissler | 12446c6 | 2007-12-19 01:27:18 +0100 | [diff] [blame] | 294 | #endif |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 295 | } |
| 296 | |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 297 | static void |
| 298 | rate_control_pid_rate_init(void *priv, struct ieee80211_supported_band *sband, |
| 299 | struct ieee80211_sta *sta, void *priv_sta) |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 300 | { |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 301 | struct rc_pid_sta_info *spinfo = priv_sta; |
Jiri Slaby | 6909268 | 2009-05-04 18:10:28 +0200 | [diff] [blame] | 302 | struct rc_pid_info *pinfo = priv; |
| 303 | struct rc_pid_rateinfo *rinfo = pinfo->rinfo; |
Jiri Slaby | 6909268 | 2009-05-04 18:10:28 +0200 | [diff] [blame] | 304 | int i, j, tmp; |
| 305 | bool s; |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 306 | |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 307 | /* TODO: This routine should consider using RSSI from previous packets |
| 308 | * as we need to have IEEE 802.1X auth succeed immediately after assoc.. |
| 309 | * Until that method is implemented, we will use the lowest supported |
| 310 | * rate as a workaround. */ |
Johannes Berg | 8318d78 | 2008-01-24 19:38:38 +0100 | [diff] [blame] | 311 | |
Stefano Brivio | 90d501d | 2007-12-19 01:26:34 +0100 | [diff] [blame] | 312 | /* Sort the rates. This is optimized for the most common case (i.e. |
| 313 | * almost-sorted CCK+OFDM rates). Kind of bubble-sort with reversed |
| 314 | * mapping too. */ |
Johannes Berg | 8318d78 | 2008-01-24 19:38:38 +0100 | [diff] [blame] | 315 | for (i = 0; i < sband->n_bitrates; i++) { |
Stefano Brivio | 90d501d | 2007-12-19 01:26:34 +0100 | [diff] [blame] | 316 | rinfo[i].index = i; |
| 317 | rinfo[i].rev_index = i; |
Mattias Nissler | adeed48 | 2008-07-07 23:08:19 +0200 | [diff] [blame] | 318 | if (RC_PID_FAST_START) |
Stefano Brivio | 90d501d | 2007-12-19 01:26:34 +0100 | [diff] [blame] | 319 | rinfo[i].diff = 0; |
| 320 | else |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 321 | rinfo[i].diff = i * pinfo->norm_offset; |
Stefano Brivio | 90d501d | 2007-12-19 01:26:34 +0100 | [diff] [blame] | 322 | } |
Johannes Berg | 8318d78 | 2008-01-24 19:38:38 +0100 | [diff] [blame] | 323 | for (i = 1; i < sband->n_bitrates; i++) { |
Stefano Brivio | 90d501d | 2007-12-19 01:26:34 +0100 | [diff] [blame] | 324 | s = 0; |
Johannes Berg | 8318d78 | 2008-01-24 19:38:38 +0100 | [diff] [blame] | 325 | for (j = 0; j < sband->n_bitrates - i; j++) |
| 326 | if (unlikely(sband->bitrates[rinfo[j].index].bitrate > |
| 327 | sband->bitrates[rinfo[j + 1].index].bitrate)) { |
Stefano Brivio | 90d501d | 2007-12-19 01:26:34 +0100 | [diff] [blame] | 328 | tmp = rinfo[j].index; |
| 329 | rinfo[j].index = rinfo[j + 1].index; |
| 330 | rinfo[j + 1].index = tmp; |
| 331 | rinfo[rinfo[j].index].rev_index = j; |
| 332 | rinfo[rinfo[j + 1].index].rev_index = j + 1; |
| 333 | s = 1; |
| 334 | } |
| 335 | if (!s) |
| 336 | break; |
| 337 | } |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 338 | |
Jiri Slaby | 6909268 | 2009-05-04 18:10:28 +0200 | [diff] [blame] | 339 | spinfo->txrate_idx = rate_lowest_index(sband, sta); |
Jiri Slaby | 6909268 | 2009-05-04 18:10:28 +0200 | [diff] [blame] | 340 | } |
| 341 | |
| 342 | static void *rate_control_pid_alloc(struct ieee80211_hw *hw, |
| 343 | struct dentry *debugfsdir) |
| 344 | { |
| 345 | struct rc_pid_info *pinfo; |
| 346 | struct rc_pid_rateinfo *rinfo; |
| 347 | struct ieee80211_supported_band *sband; |
| 348 | int i, max_rates = 0; |
| 349 | #ifdef CONFIG_MAC80211_DEBUGFS |
| 350 | struct rc_pid_debugfs_entries *de; |
| 351 | #endif |
| 352 | |
| 353 | pinfo = kmalloc(sizeof(*pinfo), GFP_ATOMIC); |
| 354 | if (!pinfo) |
| 355 | return NULL; |
| 356 | |
| 357 | for (i = 0; i < IEEE80211_NUM_BANDS; i++) { |
| 358 | sband = hw->wiphy->bands[i]; |
John W. Linville | 621ad7c | 2009-05-05 15:18:26 -0400 | [diff] [blame] | 359 | if (sband && sband->n_bitrates > max_rates) |
Jiri Slaby | 6909268 | 2009-05-04 18:10:28 +0200 | [diff] [blame] | 360 | max_rates = sband->n_bitrates; |
| 361 | } |
| 362 | |
| 363 | rinfo = kmalloc(sizeof(*rinfo) * max_rates, GFP_ATOMIC); |
| 364 | if (!rinfo) { |
| 365 | kfree(pinfo); |
| 366 | return NULL; |
| 367 | } |
| 368 | |
| 369 | pinfo->target = RC_PID_TARGET_PF; |
| 370 | pinfo->sampling_period = RC_PID_INTERVAL; |
| 371 | pinfo->coeff_p = RC_PID_COEFF_P; |
| 372 | pinfo->coeff_i = RC_PID_COEFF_I; |
| 373 | pinfo->coeff_d = RC_PID_COEFF_D; |
| 374 | pinfo->smoothing_shift = RC_PID_SMOOTHING_SHIFT; |
| 375 | pinfo->sharpen_factor = RC_PID_SHARPENING_FACTOR; |
| 376 | pinfo->sharpen_duration = RC_PID_SHARPENING_DURATION; |
| 377 | pinfo->norm_offset = RC_PID_NORM_OFFSET; |
| 378 | pinfo->rinfo = rinfo; |
| 379 | pinfo->oldrate = 0; |
| 380 | |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 381 | #ifdef CONFIG_MAC80211_DEBUGFS |
| 382 | de = &pinfo->dentries; |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 383 | de->target = debugfs_create_u32("target_pf", S_IRUSR | S_IWUSR, |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 384 | debugfsdir, &pinfo->target); |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 385 | de->sampling_period = debugfs_create_u32("sampling_period", |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 386 | S_IRUSR | S_IWUSR, debugfsdir, |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 387 | &pinfo->sampling_period); |
| 388 | de->coeff_p = debugfs_create_u32("coeff_p", S_IRUSR | S_IWUSR, |
Tomas Winkler | 9902b18 | 2008-11-08 23:50:55 +0200 | [diff] [blame] | 389 | debugfsdir, (u32 *)&pinfo->coeff_p); |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 390 | de->coeff_i = debugfs_create_u32("coeff_i", S_IRUSR | S_IWUSR, |
Tomas Winkler | 9902b18 | 2008-11-08 23:50:55 +0200 | [diff] [blame] | 391 | debugfsdir, (u32 *)&pinfo->coeff_i); |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 392 | de->coeff_d = debugfs_create_u32("coeff_d", S_IRUSR | S_IWUSR, |
Tomas Winkler | 9902b18 | 2008-11-08 23:50:55 +0200 | [diff] [blame] | 393 | debugfsdir, (u32 *)&pinfo->coeff_d); |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 394 | de->smoothing_shift = debugfs_create_u32("smoothing_shift", |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 395 | S_IRUSR | S_IWUSR, debugfsdir, |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 396 | &pinfo->smoothing_shift); |
| 397 | de->sharpen_factor = debugfs_create_u32("sharpen_factor", |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 398 | S_IRUSR | S_IWUSR, debugfsdir, |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 399 | &pinfo->sharpen_factor); |
| 400 | de->sharpen_duration = debugfs_create_u32("sharpen_duration", |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 401 | S_IRUSR | S_IWUSR, debugfsdir, |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 402 | &pinfo->sharpen_duration); |
| 403 | de->norm_offset = debugfs_create_u32("norm_offset", |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 404 | S_IRUSR | S_IWUSR, debugfsdir, |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 405 | &pinfo->norm_offset); |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 406 | #endif |
| 407 | |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 408 | return pinfo; |
| 409 | } |
| 410 | |
| 411 | static void rate_control_pid_free(void *priv) |
| 412 | { |
| 413 | struct rc_pid_info *pinfo = priv; |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 414 | #ifdef CONFIG_MAC80211_DEBUGFS |
| 415 | struct rc_pid_debugfs_entries *de = &pinfo->dentries; |
| 416 | |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 417 | debugfs_remove(de->norm_offset); |
| 418 | debugfs_remove(de->sharpen_duration); |
| 419 | debugfs_remove(de->sharpen_factor); |
| 420 | debugfs_remove(de->smoothing_shift); |
| 421 | debugfs_remove(de->coeff_d); |
| 422 | debugfs_remove(de->coeff_i); |
| 423 | debugfs_remove(de->coeff_p); |
| 424 | debugfs_remove(de->sampling_period); |
| 425 | debugfs_remove(de->target); |
Mattias Nissler | 1946b74 | 2007-12-20 13:27:26 +0100 | [diff] [blame] | 426 | #endif |
| 427 | |
Stefano Brivio | 90d501d | 2007-12-19 01:26:34 +0100 | [diff] [blame] | 428 | kfree(pinfo->rinfo); |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 429 | kfree(pinfo); |
| 430 | } |
| 431 | |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 432 | static void *rate_control_pid_alloc_sta(void *priv, struct ieee80211_sta *sta, |
| 433 | gfp_t gfp) |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 434 | { |
| 435 | struct rc_pid_sta_info *spinfo; |
| 436 | |
| 437 | spinfo = kzalloc(sizeof(*spinfo), gfp); |
Mattias Nissler | 12446c6 | 2007-12-19 01:27:18 +0100 | [diff] [blame] | 438 | if (spinfo == NULL) |
| 439 | return NULL; |
| 440 | |
Stefano Brivio | c09c723 | 2008-01-17 00:38:29 +0100 | [diff] [blame] | 441 | spinfo->last_sample = jiffies; |
| 442 | |
Mattias Nissler | 12446c6 | 2007-12-19 01:27:18 +0100 | [diff] [blame] | 443 | #ifdef CONFIG_MAC80211_DEBUGFS |
| 444 | spin_lock_init(&spinfo->events.lock); |
| 445 | init_waitqueue_head(&spinfo->events.waitqueue); |
| 446 | #endif |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 447 | |
| 448 | return spinfo; |
| 449 | } |
| 450 | |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 451 | static void rate_control_pid_free_sta(void *priv, struct ieee80211_sta *sta, |
| 452 | void *priv_sta) |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 453 | { |
Johannes Berg | 4b7679a | 2008-09-18 18:14:18 +0200 | [diff] [blame] | 454 | kfree(priv_sta); |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 455 | } |
| 456 | |
Johannes Berg | 4b47589 | 2008-01-02 15:17:03 +0100 | [diff] [blame] | 457 | static struct rate_control_ops mac80211_rcpid = { |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 458 | .name = "pid", |
| 459 | .tx_status = rate_control_pid_tx_status, |
| 460 | .get_rate = rate_control_pid_get_rate, |
| 461 | .rate_init = rate_control_pid_rate_init, |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 462 | .alloc = rate_control_pid_alloc, |
| 463 | .free = rate_control_pid_free, |
| 464 | .alloc_sta = rate_control_pid_alloc_sta, |
| 465 | .free_sta = rate_control_pid_free_sta, |
Mattias Nissler | 12446c6 | 2007-12-19 01:27:18 +0100 | [diff] [blame] | 466 | #ifdef CONFIG_MAC80211_DEBUGFS |
| 467 | .add_sta_debugfs = rate_control_pid_add_sta_debugfs, |
| 468 | .remove_sta_debugfs = rate_control_pid_remove_sta_debugfs, |
| 469 | #endif |
Mattias Nissler | ad01837 | 2007-12-19 01:25:57 +0100 | [diff] [blame] | 470 | }; |
Johannes Berg | 4b47589 | 2008-01-02 15:17:03 +0100 | [diff] [blame] | 471 | |
Johannes Berg | 4b47589 | 2008-01-02 15:17:03 +0100 | [diff] [blame] | 472 | int __init rc80211_pid_init(void) |
| 473 | { |
| 474 | return ieee80211_rate_control_register(&mac80211_rcpid); |
| 475 | } |
| 476 | |
Johannes Berg | f0b9205 | 2008-01-31 19:31:57 +0100 | [diff] [blame] | 477 | void rc80211_pid_exit(void) |
Johannes Berg | 4b47589 | 2008-01-02 15:17:03 +0100 | [diff] [blame] | 478 | { |
| 479 | ieee80211_rate_control_unregister(&mac80211_rcpid); |
| 480 | } |