blob: c230bbe93262b0affc476c01b8d1db9ab7dfe054 [file] [log] [blame]
* Copyright (C) 2008 Felix Fietkau <>
* 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
#define EWMA_LEVEL 96 /* ewma weighting factor [/EWMA_DIV] */
#define EWMA_DIV 128
#define SAMPLE_COLUMNS 10 /* number of columns in sample table */
/* scaled fraction values */
#define MINSTREL_FRAC(val, div) (((val) << MINSTREL_SCALE) / div)
#define MINSTREL_TRUNC(val) ((val) >> MINSTREL_SCALE)
/* number of highest throughput rates to consider*/
#define MAX_THR_RATES 4
* Perform EWMA (Exponentially Weighted Moving Average) calculation
static inline int
minstrel_ewma(int old, int new, int weight)
int diff, incr;
diff = new - old;
incr = (EWMA_DIV - weight) * diff / EWMA_DIV;
return old + incr;
* Perform EWMSD (Exponentially Weighted Moving Standard Deviation) calculation
static inline int
minstrel_ewmsd(int old_ewmsd, int cur_prob, int prob_ewma, int weight)
int diff, incr, tmp_var;
/* calculate exponential weighted moving variance */
diff = MINSTREL_TRUNC((cur_prob - prob_ewma) * 1000000);
incr = (EWMA_DIV - weight) * diff / EWMA_DIV;
tmp_var = old_ewmsd * old_ewmsd;
tmp_var = weight * (tmp_var + diff * incr / 1000000) / EWMA_DIV;
/* return standard deviation */
return (u16) int_sqrt(tmp_var);
struct minstrel_rate_stats {
/* current / last sampling period attempts/success counters */
u16 attempts, last_attempts;
u16 success, last_success;
/* total attempts/success counters */
u64 att_hist, succ_hist;
/* statistis of packet delivery probability
* cur_prob - current prob within last update intervall
* prob_ewma - exponential weighted moving average of prob
* prob_ewmsd - exp. weighted moving standard deviation of prob */
unsigned int cur_prob;
unsigned int prob_ewma;
u16 prob_ewmsd;
/* maximum retry counts */
u8 retry_count;
u8 retry_count_rtscts;
u8 sample_skipped;
bool retry_updated;
struct minstrel_rate {
int bitrate;
s8 rix;
u8 retry_count_cts;
u8 adjusted_retry_count;
unsigned int perfect_tx_time;
unsigned int ack_time;
int sample_limit;
struct minstrel_rate_stats stats;
struct minstrel_sta_info {
struct ieee80211_sta *sta;
unsigned long last_stats_update;
unsigned int sp_ack_dur;
unsigned int rate_avg;
unsigned int lowest_rix;
u8 max_tp_rate[MAX_THR_RATES];
u8 max_prob_rate;
unsigned int total_packets;
unsigned int sample_packets;
int sample_deferred;
unsigned int sample_row;
unsigned int sample_column;
int n_rates;
struct minstrel_rate *r;
bool prev_sample;
/* sampling table */
u8 *sample_table;
struct dentry *dbg_stats;
struct dentry *dbg_stats_csv;
struct minstrel_priv {
struct ieee80211_hw *hw;
bool has_mrr;
unsigned int cw_min;
unsigned int cw_max;
unsigned int max_retry;
unsigned int segment_size;
unsigned int update_interval;
unsigned int lookaround_rate;
unsigned int lookaround_rate_mrr;
u8 cck_rates[4];
* enable fixed rate processing per RC
* - write static index to debugfs:ieee80211/phyX/rc/fixed_rate_idx
* - write -1 to enable RC processing again
* - setting will be applied on next update
u32 fixed_rate_idx;
struct dentry *dbg_fixed_rate;
struct minstrel_debugfs_info {
size_t len;
char buf[];
extern const struct rate_control_ops mac80211_minstrel;
void minstrel_add_sta_debugfs(void *priv, void *priv_sta, struct dentry *dir);
void minstrel_remove_sta_debugfs(void *priv, void *priv_sta);
/* Recalculate success probabilities and counters for a given rate using EWMA */
void minstrel_calc_rate_stats(struct minstrel_rate_stats *mrs);
int minstrel_get_tp_avg(struct minstrel_rate *mr, int prob_ewma);
/* debugfs */
int minstrel_stats_open(struct inode *inode, struct file *file);
int minstrel_stats_csv_open(struct inode *inode, struct file *file);
ssize_t minstrel_stats_read(struct file *file, char __user *buf, size_t len, loff_t *ppos);
int minstrel_stats_release(struct inode *inode, struct file *file);