mac80211: AMPDU rx reorder timeout timer
This patch introduces a new timer, which will release
queued-up MPDUs from the reorder buffer, whenever
they've waited for more than HT_RX_REORDER_BUF_TIMEOUT
(which is at around 100 ms).
The advantage of having a dedicated timer, instead of
relying on a constant stream of freshly arriving aMPDUs
to release the old ones, is particularly observable when
even a small fraction of MPDUs are forever lost at
low network speeds.
Previously under these circumstances frames would become
stuck in the reorder buffer and the network stack of both
HT peers throttled back, instead of revving up and
gunning the pipes.
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/agg-rx.c b/net/mac80211/agg-rx.c
index 965b272..58eab9e 100644
--- a/net/mac80211/agg-rx.c
+++ b/net/mac80211/agg-rx.c
@@ -86,6 +86,7 @@
tid, 0, reason);
del_timer_sync(&tid_rx->session_timer);
+ del_timer_sync(&tid_rx->reorder_timer);
call_rcu(&tid_rx->rcu_head, ieee80211_free_tid_rx);
}
@@ -120,6 +121,20 @@
ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work);
}
+static void sta_rx_agg_reorder_timer_expired(unsigned long data)
+{
+ u8 *ptid = (u8 *)data;
+ u8 *timer_to_id = ptid - *ptid;
+ struct sta_info *sta = container_of(timer_to_id, struct sta_info,
+ timer_to_tid[0]);
+
+ rcu_read_lock();
+ spin_lock(&sta->lock);
+ ieee80211_release_reorder_timeout(sta, *ptid);
+ spin_unlock(&sta->lock);
+ rcu_read_unlock();
+}
+
static void ieee80211_send_addba_resp(struct ieee80211_sub_if_data *sdata, u8 *da, u16 tid,
u8 dialog_token, u16 status, u16 policy,
u16 buf_size, u16 timeout)
@@ -251,11 +266,18 @@
goto end;
}
+ spin_lock_init(&tid_agg_rx->reorder_lock);
+
/* 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);
+ /* rx reorder timer */
+ tid_agg_rx->reorder_timer.function = sta_rx_agg_reorder_timer_expired;
+ tid_agg_rx->reorder_timer.data = (unsigned long)&sta->timer_to_tid[tid];
+ init_timer(&tid_agg_rx->reorder_timer);
+
/* prepare reordering buffer */
tid_agg_rx->reorder_buf =
kcalloc(buf_size, sizeof(struct sk_buff *), GFP_ATOMIC);