diff options
| author | Felix Fietkau <nbd@openwrt.org> | 2012-03-19 01:58:06 +0400 |
|---|---|---|
| committer | John W. Linville <linville@tuxdriver.com> | 2012-04-10 00:09:36 +0400 |
| commit | 12d3952fc4a1cd96234bc7023bf7eefeb0bb6355 (patch) | |
| tree | 5c3437e1f996a5c772b286530a3fce547a7d40f2 /net/mac80211/agg-rx.c | |
| parent | fcb2c9e1025cd529890303ffbde813a98cdffed4 (diff) | |
| download | linux-12d3952fc4a1cd96234bc7023bf7eefeb0bb6355.tar.xz | |
mac80211: optimize aggregation session timeout handling
Calling mod_timer from the rx/tx hotpath is somewhat expensive, and the
timeout doesn't need to be so precise.
Switch to a different strategy: Schedule the timer initially, store jiffies
of all last rx/tx activity which would previously modify the timer, and
let the timer re-arm itself after checking the last rx/tx timestamp.
Make the session timers deferrable to avoid causing extra wakeups on systems
running on battery.
This visibly reduces CPU load under high network load on small embedded
systems.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Diffstat (limited to 'net/mac80211/agg-rx.c')
| -rw-r--r-- | net/mac80211/agg-rx.c | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/net/mac80211/agg-rx.c b/net/mac80211/agg-rx.c index 64d3ce5ea1a0..a070d4f460ea 100644 --- a/net/mac80211/agg-rx.c +++ b/net/mac80211/agg-rx.c @@ -142,6 +142,18 @@ static void sta_rx_agg_session_timer_expired(unsigned long data) u8 *timer_to_id = ptid - *ptid; struct sta_info *sta = container_of(timer_to_id, struct sta_info, timer_to_tid[0]); + struct tid_ampdu_rx *tid_rx; + unsigned long timeout; + + tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[*ptid]); + if (!tid_rx) + return; + + timeout = tid_rx->last_rx + TU_TO_JIFFIES(tid_rx->timeout); + if (time_is_after_jiffies(timeout)) { + mod_timer(&tid_rx->session_timer, timeout); + return; + } #ifdef CONFIG_MAC80211_HT_DEBUG printk(KERN_DEBUG "rx session timer expired on tid %d\n", (u16)*ptid); @@ -291,7 +303,7 @@ void ieee80211_process_addba_request(struct ieee80211_local *local, /* rx timer */ tid_agg_rx->session_timer.function = sta_rx_agg_session_timer_expired; tid_agg_rx->session_timer.data = (unsigned long)&sta->timer_to_tid[tid]; - init_timer(&tid_agg_rx->session_timer); + init_timer_deferrable(&tid_agg_rx->session_timer); /* rx reorder timer */ tid_agg_rx->reorder_timer.function = sta_rx_agg_reorder_timer_expired; @@ -335,8 +347,10 @@ void ieee80211_process_addba_request(struct ieee80211_local *local, /* activate it for RX */ rcu_assign_pointer(sta->ampdu_mlme.tid_rx[tid], tid_agg_rx); - if (timeout) + if (timeout) { mod_timer(&tid_agg_rx->session_timer, TU_TO_EXP_TIME(timeout)); + tid_agg_rx->last_rx = jiffies; + } end: mutex_unlock(&sta->ampdu_mlme.mtx); |