2007-12-19 00:09:56

by Stefano Brivio

[permalink] [raw]
Subject: [PATCH v2 8/8] rc80211-pid: export tuning parameters through debugfs

From: Mattias Nissler <[email protected]>

This adds all the tunable parameters used by rc80211_pid to debugfs for easy
testing and tuning.

Signed-off-by: Mattias Nissler <[email protected]>
---
rc80211_pid.h | 23 ++++++++++-
rc80211_pid_algo.c | 106
+++++++++++++++++++++++++++++++++++++++++++---------- 2 files changed, 107
insertions(+), 22 deletions(-)

Index: wireless-2.6/net/mac80211/rc80211_pid_algo.c
===================================================================
--- wireless-2.6.orig/net/mac80211/rc80211_pid_algo.c
+++ wireless-2.6/net/mac80211/rc80211_pid_algo.c
@@ -139,19 +139,20 @@ static void rate_control_pid_adjust_rate
}

/* Normalize the failed frames per-rate differences. */
-static void rate_control_pid_normalize(struct rc_pid_rateinfo *r, int l)
+static void rate_control_pid_normalize(struct rc_pid_info *pinfo, int l)
{
- int i;
+ int i, norm_offset = pinfo->norm_offset;
+ struct rc_pid_rateinfo *r = pinfo->rinfo;

- if (r[0].diff > RC_PID_NORM_OFFSET)
- r[0].diff -= RC_PID_NORM_OFFSET;
- else if (r[0].diff < -RC_PID_NORM_OFFSET)
- r[0].diff += RC_PID_NORM_OFFSET;
+ if (r[0].diff > norm_offset)
+ r[0].diff -= norm_offset;
+ else if (r[0].diff < -norm_offset)
+ r[0].diff += norm_offset;
for (i = 0; i < l - 1; i++)
- if (r[i + 1].diff > r[i].diff + RC_PID_NORM_OFFSET)
- r[i + 1].diff -= RC_PID_NORM_OFFSET;
+ if (r[i + 1].diff > r[i].diff + norm_offset)
+ r[i + 1].diff -= norm_offset;
else if (r[i + 1].diff <= r[i].diff)
- r[i + 1].diff += RC_PID_NORM_OFFSET;
+ r[i + 1].diff += norm_offset;
}

static void rate_control_pid_sample(struct rc_pid_info *pinfo,
@@ -167,14 +168,18 @@ static void rate_control_pid_sample(stru
s32 err_int;
s32 err_der;
int adj, i, j, tmp;
+ unsigned long period;

mode = local->oper_hw_mode;
spinfo = sta->rate_ctrl_priv;

/* In case nothing happened during the previous control interval,
turn
* the sharpening factor on. */
- if (jiffies - spinfo->last_sample > 2 * RC_PID_INTERVAL)
- spinfo->sharp_cnt = RC_PID_SHARPENING_DURATION;
+ period = (HZ * pinfo->sampling_period + 500) / 1000;
+ if (!period)
+ period = 1;
+ if (jiffies - spinfo->last_sample > 2 * period)
+ spinfo->sharp_cnt = pinfo->sharpen_duration;

spinfo->last_sample = jiffies;

@@ -202,17 +207,17 @@ static void rate_control_pid_sample(stru
rinfo[j].diff = rinfo[i].diff + tmp;
pinfo->oldrate = sta->txrate;
}
- rate_control_pid_normalize(rinfo, mode->num_rates);
+ rate_control_pid_normalize(pinfo, mode->num_rates);

/* Compute the proportional, integral and derivative errors. */
- err_prop = RC_PID_TARGET_PF - pf;
+ err_prop = pinfo->target - pf;

- err_avg = spinfo->err_avg_sc >> RC_PID_SMOOTHING_SHIFT;
+ err_avg = spinfo->err_avg_sc >> pinfo->smoothing_shift;
spinfo->err_avg_sc = spinfo->err_avg_sc - err_avg + err_prop;
- err_int = spinfo->err_avg_sc >> RC_PID_SMOOTHING_SHIFT;
+ err_int = spinfo->err_avg_sc >> pinfo->smoothing_shift;

- err_der = pf - spinfo->last_pf
- * (1 + RC_PID_SHARPENING_FACTOR * spinfo->sharp_cnt);
+ err_der = (pf - spinfo->last_pf) *
+ (1 + pinfo->sharpen_factor * spinfo->sharp_cnt);
spinfo->last_pf = pf;
if (spinfo->sharp_cnt)
spinfo->sharp_cnt--;
@@ -241,6 +246,7 @@ static void rate_control_pid_tx_status(v
struct rc_pid_info *pinfo = priv;
struct sta_info *sta;
struct rc_pid_sta_info *spinfo;
+ unsigned long period;

sta = sta_info_get(local, hdr->addr1);

@@ -285,7 +291,10 @@ static void rate_control_pid_tx_status(v
sta->tx_num_mpdu_fail += status->retry_count;

/* Update PID controller state. */
- if (time_after(jiffies, spinfo->last_sample + RC_PID_INTERVAL))
+ period = (HZ * pinfo->sampling_period + 500) / 1000;
+ if (!period)
+ period = 1;
+ if (time_after(jiffies, spinfo->last_sample + period))
rate_control_pid_sample(pinfo, local, sta);

sta_info_put(sta);
@@ -343,6 +352,9 @@ static void *rate_control_pid_alloc(stru
struct ieee80211_hw_mode *mode;
int i, j, tmp;
bool s;
+#ifdef CONFIG_MAC80211_DEBUGFS
+ struct rc_pid_debugfs_entries *de;
+#endif

pinfo = kmalloc(sizeof(*pinfo), GFP_ATOMIC);
if (!pinfo)
@@ -363,10 +375,10 @@ static void *rate_control_pid_alloc(stru
for (i = 0; i < mode->num_rates; i++) {
rinfo[i].index = i;
rinfo[i].rev_index = i;
- if (RC_PID_FAST_START)
+ if (pinfo->fast_start)
rinfo[i].diff = 0;
else
- rinfo[i].diff = i * RC_PID_NORM_OFFSET;
+ rinfo[i].diff = i * pinfo->norm_offset;
}
for (i = 1; i < mode->num_rates; i++) {
s = 0;
@@ -385,18 +397,72 @@ static void *rate_control_pid_alloc(stru
}

pinfo->target = RC_PID_TARGET_PF;
+ pinfo->sampling_period = RC_PID_INTERVAL;
pinfo->coeff_p = RC_PID_COEFF_P;
pinfo->coeff_i = RC_PID_COEFF_I;
pinfo->coeff_d = RC_PID_COEFF_D;
+ pinfo->smoothing_shift = RC_PID_SMOOTHING_SHIFT;
+ pinfo->sharpen_factor = RC_PID_SHARPENING_FACTOR;
+ pinfo->sharpen_duration = RC_PID_SHARPENING_DURATION;
+ pinfo->norm_offset = RC_PID_NORM_OFFSET;
+ pinfo->fast_start = RC_PID_FAST_START;
pinfo->rinfo = rinfo;
pinfo->oldrate = 0;

+#ifdef CONFIG_MAC80211_DEBUGFS
+ de = &pinfo->dentries;
+ de->dir = debugfs_create_dir("rc80211_pid",
+ local->hw.wiphy->debugfsdir);
+ de->target = debugfs_create_u32("target_pf", S_IRUSR | S_IWUSR,
+ de->dir, &pinfo->target);
+ de->sampling_period = debugfs_create_u32("sampling_period",
+ S_IRUSR | S_IWUSR,
de->dir,
+ &pinfo->sampling_period);
+ de->coeff_p = debugfs_create_s32("coeff_p", S_IRUSR | S_IWUSR,
+ de->dir, &pinfo->coeff_p);
+ de->coeff_i = debugfs_create_s32("coeff_i", S_IRUSR | S_IWUSR,
+ de->dir, &pinfo->coeff_i);
+ de->coeff_d = debugfs_create_s32("coeff_d", S_IRUSR | S_IWUSR,
+ de->dir, &pinfo->coeff_d);
+ de->smoothing_shift = debugfs_create_u32("smoothing_shift",
+ S_IRUSR | S_IWUSR,
de->dir,
+ &pinfo->smoothing_shift);
+ de->sharpen_factor = debugfs_create_u32("sharpen_factor",
+ S_IRUSR | S_IWUSR, de->dir,
+ &pinfo->sharpen_factor);
+ de->sharpen_duration = debugfs_create_u32("sharpen_duration",
+ S_IRUSR | S_IWUSR,
de->dir,
+
&pinfo->sharpen_duration);
+ de->norm_offset = debugfs_create_u32("norm_offset",
+ S_IRUSR | S_IWUSR, de->dir,
+ &pinfo->norm_offset);
+ de->fast_start = debugfs_create_bool("fast_start",
+ S_IRUSR | S_IWUSR, de->dir,
+ &pinfo->fast_start);
+#endif
+
return pinfo;
}

static void rate_control_pid_free(void *priv)
{
struct rc_pid_info *pinfo = priv;
+#ifdef CONFIG_MAC80211_DEBUGFS
+ struct rc_pid_debugfs_entries *de = &pinfo->dentries;
+
+ debugfs_remove(de->fast_start);
+ debugfs_remove(de->norm_offset);
+ debugfs_remove(de->sharpen_duration);
+ debugfs_remove(de->sharpen_factor);
+ debugfs_remove(de->smoothing_shift);
+ debugfs_remove(de->coeff_d);
+ debugfs_remove(de->coeff_i);
+ debugfs_remove(de->coeff_p);
+ debugfs_remove(de->sampling_period);
+ debugfs_remove(de->target);
+ debugfs_remove(de->dir);
+#endif
+
kfree(pinfo->rinfo);
kfree(pinfo);
}
Index: wireless-2.6/net/mac80211/rc80211_pid.h
===================================================================
--- wireless-2.6.orig/net/mac80211/rc80211_pid.h
+++ wireless-2.6/net/mac80211/rc80211_pid.h
@@ -119,6 +119,20 @@ struct rc_pid_events_file_info {
unsigned int next_entry;
};

+struct rc_pid_debugfs_entries {
+ struct dentry *dir;
+ struct dentry *target;
+ struct dentry *sampling_period;
+ struct dentry *coeff_p;
+ struct dentry *coeff_i;
+ struct dentry *coeff_d;
+ struct dentry *smoothing_shift;
+ struct dentry *sharpen_factor;
+ struct dentry *sharpen_duration;
+ struct dentry *norm_offset;
+ struct dentry *fast_start;
+};
+
void rate_control_pid_event_tx_status(struct rc_pid_event_buffer *buf,
struct ieee80211_tx_status
*stat);

@@ -222,8 +236,8 @@ struct rc_pid_info {
/* Exponential averaging shift. */
unsigned int smoothing_shift;

- /* Sharpening shift and duration. */
- unsigned int sharpen_shift;
+ /* Sharpening factor and duration. */
+ unsigned int sharpen_factor;
unsigned int sharpen_duration;

/* Normalization offset. */
@@ -237,6 +251,11 @@ struct rc_pid_info {

/* Index of the last used rate. */
int oldrate;
+
+#ifdef CONFIG_MAC80211_DEBUGFS
+ /* Debugfs entries created for the parameters above. */
+ struct rc_pid_debugfs_entries dentries;
+#endif
};

#endif /* RC80211_PID_H */

--
Ciao
Stefano