tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Copyright (C) 2008 Felix Fietkau <nbd@openwrt.org>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 */
8
9#ifndef __RC_MINSTREL_H
10#define __RC_MINSTREL_H
11
12#define EWMA_LEVEL 96 /* ewma weighting factor [/EWMA_DIV] */
13#define EWMA_DIV 128
14#define SAMPLE_COLUMNS 10 /* number of columns in sample table */
15
16/* scaled fraction values */
17#define MINSTREL_SCALE 12
18#define MINSTREL_FRAC(val, div) (((val) << MINSTREL_SCALE) / div)
19#define MINSTREL_TRUNC(val) ((val) >> MINSTREL_SCALE)
20
21/* number of highest throughput rates to consider*/
22#define MAX_THR_RATES 4
23
24/*
25 * Perform EWMA (Exponentially Weighted Moving Average) calculation
26 */
27static inline int
28minstrel_ewma(int old, int new, int weight)
29{
30 int diff, incr;
31
32 diff = new - old;
33 incr = (EWMA_DIV - weight) * diff / EWMA_DIV;
34
35 return old + incr;
36}
37
38/*
39 * Perform EWMV (Exponentially Weighted Moving Variance) calculation
40 */
41static inline int
42minstrel_ewmv(int old_ewmv, int cur_prob, int prob_ewma, int weight)
43{
44 int diff, incr;
45
46 diff = cur_prob - prob_ewma;
47 incr = (EWMA_DIV - weight) * diff / EWMA_DIV;
48 return weight * (old_ewmv + MINSTREL_TRUNC(diff * incr)) / EWMA_DIV;
49}
50
51struct minstrel_rate_stats {
52 /* current / last sampling period attempts/success counters */
53 u16 attempts, last_attempts;
54 u16 success, last_success;
55
56 /* total attempts/success counters */
57 u32 att_hist, succ_hist;
58
59 /* statistis of packet delivery probability
60 * prob_ewma - exponential weighted moving average of prob
61 * prob_ewmsd - exp. weighted moving standard deviation of prob */
62 u16 prob_ewma;
63 u16 prob_ewmv;
64
65 /* maximum retry counts */
66 u8 retry_count;
67 u8 retry_count_rtscts;
68
69 u8 sample_skipped;
70 bool retry_updated;
71};
72
73struct minstrel_rate {
74 int bitrate;
75
76 s8 rix;
77 u8 retry_count_cts;
78 u8 adjusted_retry_count;
79
80 unsigned int perfect_tx_time;
81 unsigned int ack_time;
82
83 int sample_limit;
84
85 struct minstrel_rate_stats stats;
86};
87
88struct minstrel_sta_info {
89 struct ieee80211_sta *sta;
90
91 unsigned long last_stats_update;
92 unsigned int sp_ack_dur;
93 unsigned int rate_avg;
94
95 unsigned int lowest_rix;
96
97 u8 max_tp_rate[MAX_THR_RATES];
98 u8 max_prob_rate;
99 unsigned int total_packets;
100 unsigned int sample_packets;
101 int sample_deferred;
102
103 unsigned int sample_row;
104 unsigned int sample_column;
105
106 int n_rates;
107 struct minstrel_rate *r;
108 bool prev_sample;
109
110 /* sampling table */
111 u8 *sample_table;
112
113#ifdef CONFIG_MAC80211_DEBUGFS
114 struct dentry *dbg_stats;
115 struct dentry *dbg_stats_csv;
116#endif
117};
118
119struct minstrel_priv {
120 struct ieee80211_hw *hw;
121 bool has_mrr;
122 unsigned int cw_min;
123 unsigned int cw_max;
124 unsigned int max_retry;
125 unsigned int segment_size;
126 unsigned int update_interval;
127 unsigned int lookaround_rate;
128 unsigned int lookaround_rate_mrr;
129
130 u8 cck_rates[4];
131
132#ifdef CONFIG_MAC80211_DEBUGFS
133 /*
134 * enable fixed rate processing per RC
135 * - write static index to debugfs:ieee80211/phyX/rc/fixed_rate_idx
136 * - write -1 to enable RC processing again
137 * - setting will be applied on next update
138 */
139 u32 fixed_rate_idx;
140 struct dentry *dbg_fixed_rate;
141#endif
142};
143
144struct minstrel_debugfs_info {
145 size_t len;
146 char buf[];
147};
148
149/* Get EWMSD (Exponentially Weighted Moving Standard Deviation) * 10 */
150static inline int
151minstrel_get_ewmsd10(struct minstrel_rate_stats *mrs)
152{
153 unsigned int ewmv = mrs->prob_ewmv;
154 return int_sqrt(MINSTREL_TRUNC(ewmv * 1000 * 1000));
155}
156
157extern const struct rate_control_ops mac80211_minstrel;
158void minstrel_add_sta_debugfs(void *priv, void *priv_sta, struct dentry *dir);
159void minstrel_remove_sta_debugfs(void *priv, void *priv_sta);
160
161/* Recalculate success probabilities and counters for a given rate using EWMA */
162void minstrel_calc_rate_stats(struct minstrel_rate_stats *mrs);
163int minstrel_get_tp_avg(struct minstrel_rate *mr, int prob_ewma);
164
165/* debugfs */
166int minstrel_stats_open(struct inode *inode, struct file *file);
167int minstrel_stats_csv_open(struct inode *inode, struct file *file);
168ssize_t minstrel_stats_read(struct file *file, char __user *buf, size_t len, loff_t *ppos);
169int minstrel_stats_release(struct inode *inode, struct file *file);
170
171#endif