Star64_linux/drivers/net/wireless/ath/ath9k/debug_sta.c
Toke Høiland-Jørgensen 63fefa0504 ath9k: Introduce airtime fairness scheduling between stations
This reworks the ath9k driver to schedule transmissions to connected
stations in a way that enforces airtime fairness between them. It
accomplishes this by measuring the time spent transmitting to or
receiving from a station at TX and RX completion, and accounting this to
a per-station, per-QoS level airtime deficit. Then, an FQ-CoDel based
deficit scheduler is employed at packet dequeue time, to control which
station gets the next transmission opportunity.

Airtime fairness can significantly improve the efficiency of the network
when station rates vary. The following throughput values are from a
simple three-station test scenario, where two stations operate at the
highest HT20 rate, and one station at the lowest, and the scheduler is
employed at the access point:

                  Before   /   After
Fast station 1:    19.17   /   25.09 Mbps
Fast station 2:    19.83   /   25.21 Mbps
Slow station:       2.58   /    1.77 Mbps
Total:             41.58   /   52.07 Mbps

The benefit of airtime fairness goes up the more stations are present.
In a 30-station test with one station artificially limited to 1 Mbps,
we have seen aggregate throughput go from 2.14 to 17.76 Mbps.

Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
2016-12-15 10:43:05 +02:00

308 lines
7.6 KiB
C

/*
* Copyright (c) 2013 Qualcomm Atheros, Inc.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include "ath9k.h"
/*************/
/* node_aggr */
/*************/
static ssize_t read_file_node_aggr(struct file *file, char __user *user_buf,
size_t count, loff_t *ppos)
{
struct ath_node *an = file->private_data;
struct ath_softc *sc = an->sc;
struct ath_atx_tid *tid;
struct ath_txq *txq;
u32 len = 0, size = 4096;
char *buf;
size_t retval;
int tidno;
buf = kzalloc(size, GFP_KERNEL);
if (buf == NULL)
return -ENOMEM;
if (!an->sta->ht_cap.ht_supported) {
len = scnprintf(buf, size, "%s\n",
"HT not supported");
goto exit;
}
len = scnprintf(buf, size, "Max-AMPDU: %d\n",
an->maxampdu);
len += scnprintf(buf + len, size - len, "MPDU Density: %d\n\n",
an->mpdudensity);
len += scnprintf(buf + len, size - len,
"\n%3s%11s%10s%10s%10s%10s%9s%6s%8s\n",
"TID", "SEQ_START", "SEQ_NEXT", "BAW_SIZE",
"BAW_HEAD", "BAW_TAIL", "BAR_IDX", "SCHED", "PAUSED");
for (tidno = 0; tidno < IEEE80211_NUM_TIDS; tidno++) {
tid = ath_node_to_tid(an, tidno);
txq = tid->txq;
ath_txq_lock(sc, txq);
if (tid->active) {
len += scnprintf(buf + len, size - len,
"%3d%11d%10d%10d%10d%10d%9d%6d\n",
tid->tidno,
tid->seq_start,
tid->seq_next,
tid->baw_size,
tid->baw_head,
tid->baw_tail,
tid->bar_index,
!list_empty(&tid->list));
}
ath_txq_unlock(sc, txq);
}
exit:
retval = simple_read_from_buffer(user_buf, count, ppos, buf, len);
kfree(buf);
return retval;
}
static const struct file_operations fops_node_aggr = {
.read = read_file_node_aggr,
.open = simple_open,
.owner = THIS_MODULE,
.llseek = default_llseek,
};
/*************/
/* node_recv */
/*************/
void ath_debug_rate_stats(struct ath_softc *sc,
struct ath_rx_status *rs,
struct sk_buff *skb)
{
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
struct ath_hw *ah = sc->sc_ah;
struct ieee80211_rx_status *rxs;
struct ath_rx_rate_stats *rstats;
struct ieee80211_sta *sta;
struct ath_node *an;
if (!ieee80211_is_data(hdr->frame_control))
return;
rcu_read_lock();
sta = ieee80211_find_sta_by_ifaddr(sc->hw, hdr->addr2, NULL);
if (!sta)
goto exit;
an = (struct ath_node *) sta->drv_priv;
rstats = &an->rx_rate_stats;
rxs = IEEE80211_SKB_RXCB(skb);
if (IS_HT_RATE(rs->rs_rate)) {
if (rxs->rate_idx >= ARRAY_SIZE(rstats->ht_stats))
goto exit;
if (rxs->flag & RX_FLAG_40MHZ)
rstats->ht_stats[rxs->rate_idx].ht40_cnt++;
else
rstats->ht_stats[rxs->rate_idx].ht20_cnt++;
if (rxs->flag & RX_FLAG_SHORT_GI)
rstats->ht_stats[rxs->rate_idx].sgi_cnt++;
else
rstats->ht_stats[rxs->rate_idx].lgi_cnt++;
goto exit;
}
if (IS_CCK_RATE(rs->rs_rate)) {
if (rxs->flag & RX_FLAG_SHORTPRE)
rstats->cck_stats[rxs->rate_idx].cck_sp_cnt++;
else
rstats->cck_stats[rxs->rate_idx].cck_lp_cnt++;
goto exit;
}
if (IS_OFDM_RATE(rs->rs_rate)) {
if (ah->curchan->chan->band == NL80211_BAND_2GHZ)
rstats->ofdm_stats[rxs->rate_idx - 4].ofdm_cnt++;
else
rstats->ofdm_stats[rxs->rate_idx].ofdm_cnt++;
}
exit:
rcu_read_unlock();
}
#define PRINT_CCK_RATE(str, i, sp) \
do { \
len += scnprintf(buf + len, size - len, \
"%11s : %10u\n", \
str, \
(sp) ? rstats->cck_stats[i].cck_sp_cnt : \
rstats->cck_stats[i].cck_lp_cnt); \
} while (0)
#define PRINT_OFDM_RATE(str, i) \
do { \
len += scnprintf(buf + len, size - len, \
"%11s : %10u\n", \
str, \
rstats->ofdm_stats[i].ofdm_cnt); \
} while (0)
static ssize_t read_file_node_recv(struct file *file, char __user *user_buf,
size_t count, loff_t *ppos)
{
struct ath_node *an = file->private_data;
struct ath_softc *sc = an->sc;
struct ath_hw *ah = sc->sc_ah;
struct ath_rx_rate_stats *rstats;
struct ieee80211_sta *sta = an->sta;
enum nl80211_band band;
u32 len = 0, size = 4096;
char *buf;
size_t retval;
int i;
buf = kzalloc(size, GFP_KERNEL);
if (buf == NULL)
return -ENOMEM;
band = ah->curchan->chan->band;
rstats = &an->rx_rate_stats;
if (!sta->ht_cap.ht_supported)
goto legacy;
len += scnprintf(buf + len, size - len,
"%24s%10s%10s%10s\n",
"HT20", "HT40", "SGI", "LGI");
for (i = 0; i < 24; i++) {
len += scnprintf(buf + len, size - len,
"%8s%3u : %10u%10u%10u%10u\n",
"MCS", i,
rstats->ht_stats[i].ht20_cnt,
rstats->ht_stats[i].ht40_cnt,
rstats->ht_stats[i].sgi_cnt,
rstats->ht_stats[i].lgi_cnt);
}
len += scnprintf(buf + len, size - len, "\n");
legacy:
if (band == NL80211_BAND_2GHZ) {
PRINT_CCK_RATE("CCK-1M/LP", 0, false);
PRINT_CCK_RATE("CCK-2M/LP", 1, false);
PRINT_CCK_RATE("CCK-5.5M/LP", 2, false);
PRINT_CCK_RATE("CCK-11M/LP", 3, false);
PRINT_CCK_RATE("CCK-2M/SP", 1, true);
PRINT_CCK_RATE("CCK-5.5M/SP", 2, true);
PRINT_CCK_RATE("CCK-11M/SP", 3, true);
}
PRINT_OFDM_RATE("OFDM-6M", 0);
PRINT_OFDM_RATE("OFDM-9M", 1);
PRINT_OFDM_RATE("OFDM-12M", 2);
PRINT_OFDM_RATE("OFDM-18M", 3);
PRINT_OFDM_RATE("OFDM-24M", 4);
PRINT_OFDM_RATE("OFDM-36M", 5);
PRINT_OFDM_RATE("OFDM-48M", 6);
PRINT_OFDM_RATE("OFDM-54M", 7);
retval = simple_read_from_buffer(user_buf, count, ppos, buf, len);
kfree(buf);
return retval;
}
#undef PRINT_OFDM_RATE
#undef PRINT_CCK_RATE
static const struct file_operations fops_node_recv = {
.read = read_file_node_recv,
.open = simple_open,
.owner = THIS_MODULE,
.llseek = default_llseek,
};
void ath_debug_airtime(struct ath_softc *sc,
struct ath_node *an,
u32 rx,
u32 tx)
{
struct ath_airtime_stats *astats = &an->airtime_stats;
astats->rx_airtime += rx;
astats->tx_airtime += tx;
}
static ssize_t read_airtime(struct file *file, char __user *user_buf,
size_t count, loff_t *ppos)
{
struct ath_node *an = file->private_data;
struct ath_airtime_stats *astats;
static const char *qname[4] = {
"VO", "VI", "BE", "BK"
};
u32 len = 0, size = 256;
char *buf;
size_t retval;
int i;
buf = kzalloc(size, GFP_KERNEL);
if (buf == NULL)
return -ENOMEM;
astats = &an->airtime_stats;
len += scnprintf(buf + len, size - len, "RX: %u us\n", astats->rx_airtime);
len += scnprintf(buf + len, size - len, "TX: %u us\n", astats->tx_airtime);
len += scnprintf(buf + len, size - len, "Deficit: ");
for (i = 0; i < 4; i++)
len += scnprintf(buf+len, size - len, "%s: %lld us ", qname[i], an->airtime_deficit[i]);
if (len < size)
buf[len++] = '\n';
retval = simple_read_from_buffer(user_buf, count, ppos, buf, len);
kfree(buf);
return retval;
}
static const struct file_operations fops_airtime = {
.read = read_airtime,
.open = simple_open,
.owner = THIS_MODULE,
.llseek = default_llseek,
};
void ath9k_sta_add_debugfs(struct ieee80211_hw *hw,
struct ieee80211_vif *vif,
struct ieee80211_sta *sta,
struct dentry *dir)
{
struct ath_node *an = (struct ath_node *)sta->drv_priv;
debugfs_create_file("node_aggr", S_IRUGO, dir, an, &fops_node_aggr);
debugfs_create_file("node_recv", S_IRUGO, dir, an, &fops_node_recv);
debugfs_create_file("airtime", S_IRUGO, dir, an, &fops_airtime);
}