/* * 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_SCALE 16 #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; #ifdef CONFIG_MAC80211_DEBUGFS struct dentry *dbg_stats; struct dentry *dbg_stats_csv; #endif }; 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]; #ifdef CONFIG_MAC80211_DEBUGFS /* * 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; #endif }; 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); #endif