From 12d3952fc4a1cd96234bc7023bf7eefeb0bb6355 Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Sun, 18 Mar 2012 22:58:06 +0100 Subject: 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 Signed-off-by: John W. Linville --- net/mac80211/sta_info.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'net/mac80211/sta_info.h') diff --git a/net/mac80211/sta_info.h b/net/mac80211/sta_info.h index ab0576827baf..e21652bccf7c 100644 --- a/net/mac80211/sta_info.h +++ b/net/mac80211/sta_info.h @@ -101,6 +101,7 @@ enum ieee80211_sta_info_flags { * @dialog_token: dialog token for aggregation session * @timeout: session timeout value to be filled in ADDBA requests * @state: session state (see above) + * @last_tx: jiffies of last tx activity * @stop_initiator: initiator of a session stop * @tx_stop: TX DelBA frame when stopping * @buf_size: reorder buffer size at receiver @@ -122,6 +123,7 @@ struct tid_ampdu_tx { struct timer_list addba_resp_timer; struct sk_buff_head pending; unsigned long state; + unsigned long last_tx; u16 timeout; u8 dialog_token; u8 stop_initiator; @@ -139,6 +141,7 @@ struct tid_ampdu_tx { * @reorder_time: jiffies when skb was added * @session_timer: check if peer keeps Tx-ing on the TID (by timeout value) * @reorder_timer: releases expired frames from the reorder buffer. + * @last_rx: jiffies of last rx activity * @head_seq_num: head sequence number in reordering buffer. * @stored_mpdu_num: number of MPDUs in reordering buffer * @ssn: Starting Sequence Number expected to be aggregated. @@ -163,6 +166,7 @@ struct tid_ampdu_rx { unsigned long *reorder_time; struct timer_list session_timer; struct timer_list reorder_timer; + unsigned long last_rx; u16 head_seq_num; u16 stored_mpdu_num; u16 ssn; -- cgit v1.2.1