linux/net/mac80211/rc80211_minstrel_ht_debugfs.c
Karl Beldan 8ec7886b1c mac80211: minstrel_ht: use group flags instead of index to display rates
When displaying a rate through debugfs minstrel_ht guesses its flags
comparing group indexes.  Since 3ec373c421 ("mac80211: minstrel_ht:
include type (cck/ht) in rates flag"), the rate flags of interest are
present in the mcs_group-s, so use it.
While improving the code, this also fixes a smatch false positive
"error: testing array offset 'i' after use" in minstrel_ht_stats_dump.
This warning only triggers after 9208247d74 ("mac80211: minstrel_ht:
add basic support for VHT rates <= 3SS@80MHz") with
CONFIG_MAC80211_RC_MINSTREL_VHT unset because then MINSTREL_VHT_GROUP_0
is above MINSTREL_GROUPS_NB and smatch only barks when the "testing
array offset" seems to prevent possible out of bonds accesses (which
does not happen here since i < ARRAY_SIZE(mi->groups)).

Signed-off-by: Karl Beldan <karl.beldan@rivierawaves.com>
Cc: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-10-23 20:36:13 +02:00

160 lines
4.2 KiB
C

/*
* Copyright (C) 2010 Felix Fietkau <nbd@openwrt.org>
*
* 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.
*/
#include <linux/netdevice.h>
#include <linux/types.h>
#include <linux/skbuff.h>
#include <linux/debugfs.h>
#include <linux/ieee80211.h>
#include <linux/export.h>
#include <net/mac80211.h>
#include "rc80211_minstrel.h"
#include "rc80211_minstrel_ht.h"
static char *
minstrel_ht_stats_dump(struct minstrel_ht_sta *mi, int i, char *p)
{
const struct mcs_group *mg;
unsigned int j, tp, prob, eprob;
char htmode = '2';
char gimode = 'L';
u32 gflags;
if (!mi->groups[i].supported)
return p;
mg = &minstrel_mcs_groups[i];
gflags = mg->flags;
if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH)
htmode = '4';
else if (gflags & IEEE80211_TX_RC_80_MHZ_WIDTH)
htmode = '8';
if (gflags & IEEE80211_TX_RC_SHORT_GI)
gimode = 'S';
for (j = 0; j < MCS_GROUP_RATES; j++) {
struct minstrel_rate_stats *mr = &mi->groups[i].rates[j];
static const int bitrates[4] = { 10, 20, 55, 110 };
int idx = i * MCS_GROUP_RATES + j;
if (!(mi->groups[i].supported & BIT(j)))
continue;
if (gflags & IEEE80211_TX_RC_MCS)
p += sprintf(p, " HT%c0/%cGI ", htmode, gimode);
else if (gflags & IEEE80211_TX_RC_VHT_MCS)
p += sprintf(p, "VHT%c0/%cGI ", htmode, gimode);
else
p += sprintf(p, " CCK/%cP ", j < 4 ? 'L' : 'S');
*(p++) = (idx == mi->max_tp_rate[0]) ? 'A' : ' ';
*(p++) = (idx == mi->max_tp_rate[1]) ? 'B' : ' ';
*(p++) = (idx == mi->max_tp_rate[2]) ? 'C' : ' ';
*(p++) = (idx == mi->max_tp_rate[3]) ? 'D' : ' ';
*(p++) = (idx == mi->max_prob_rate) ? 'P' : ' ';
if (gflags & IEEE80211_TX_RC_MCS) {
p += sprintf(p, " MCS%-2u ", (mg->streams - 1) * 8 + j);
} else if (gflags & IEEE80211_TX_RC_VHT_MCS) {
p += sprintf(p, " MCS%-1u/%1u", j, mg->streams);
} else {
int r = bitrates[j % 4];
p += sprintf(p, " %2u.%1uM ", r / 10, r % 10);
}
tp = mr->cur_tp / 10;
prob = MINSTREL_TRUNC(mr->cur_prob * 1000);
eprob = MINSTREL_TRUNC(mr->probability * 1000);
p += sprintf(p, " %4u.%1u %3u.%1u %3u.%1u "
"%3u %4u(%4u) %9llu(%9llu)\n",
tp / 10, tp % 10,
eprob / 10, eprob % 10,
prob / 10, prob % 10,
mr->retry_count,
mr->last_success,
mr->last_attempts,
(unsigned long long)mr->succ_hist,
(unsigned long long)mr->att_hist);
}
return p;
}
static int
minstrel_ht_stats_open(struct inode *inode, struct file *file)
{
struct minstrel_ht_sta_priv *msp = inode->i_private;
struct minstrel_ht_sta *mi = &msp->ht;
struct minstrel_debugfs_info *ms;
unsigned int i;
char *p;
int ret;
if (!msp->is_ht) {
inode->i_private = &msp->legacy;
ret = minstrel_stats_open(inode, file);
inode->i_private = msp;
return ret;
}
ms = kmalloc(32768, GFP_KERNEL);
if (!ms)
return -ENOMEM;
file->private_data = ms;
p = ms->buf;
p += sprintf(p, " type rate tpt eprob *prob "
"ret *ok(*cum) ok( cum)\n");
p = minstrel_ht_stats_dump(mi, MINSTREL_CCK_GROUP, p);
for (i = 0; i < MINSTREL_CCK_GROUP; i++)
p = minstrel_ht_stats_dump(mi, i, p);
for (i++; i < ARRAY_SIZE(mi->groups); i++)
p = minstrel_ht_stats_dump(mi, i, p);
p += sprintf(p, "\nTotal packet count:: ideal %d "
"lookaround %d\n",
max(0, (int) mi->total_packets - (int) mi->sample_packets),
mi->sample_packets);
p += sprintf(p, "Average A-MPDU length: %d.%d\n",
MINSTREL_TRUNC(mi->avg_ampdu_len),
MINSTREL_TRUNC(mi->avg_ampdu_len * 10) % 10);
ms->len = p - ms->buf;
WARN_ON(ms->len + sizeof(*ms) > 32768);
return nonseekable_open(inode, file);
}
static const struct file_operations minstrel_ht_stat_fops = {
.owner = THIS_MODULE,
.open = minstrel_ht_stats_open,
.read = minstrel_stats_read,
.release = minstrel_stats_release,
.llseek = no_llseek,
};
void
minstrel_ht_add_sta_debugfs(void *priv, void *priv_sta, struct dentry *dir)
{
struct minstrel_ht_sta_priv *msp = priv_sta;
msp->dbg_stats = debugfs_create_file("rc_stats", S_IRUGO, dir, msp,
&minstrel_ht_stat_fops);
}
void
minstrel_ht_remove_sta_debugfs(void *priv, void *priv_sta)
{
struct minstrel_ht_sta_priv *msp = priv_sta;
debugfs_remove(msp->dbg_stats);
}