Return-path: Received: from mail-pb0-f50.google.com ([209.85.160.50]:61599 "EHLO mail-pb0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751290Ab3CSLI2 (ORCPT ); Tue, 19 Mar 2013 07:08:28 -0400 Received: by mail-pb0-f50.google.com with SMTP id up1so338001pbc.37 for ; Tue, 19 Mar 2013 04:08:28 -0700 (PDT) From: "Luis R. Rodriguez" To: johannes@sipsolutions.net Cc: linux-wireless@vger.kernel.org, "Luis R. Rodriguez" Subject: [RFC] mac80211: avoid rearming BA session timers unnecessarily Date: Tue, 19 Mar 2013 04:08:22 -0700 Message-Id: <1363691302-11947-1-git-send-email-mcgrof@do-not-panic.com> (sfid-20130319_120833_510818_F0C8EF46) Sender: linux-wireless-owner@vger.kernel.org List-ID: From: "Luis R. Rodriguez" If mac80211 tears down the BA sessions with del_timer_sync() technically mod_timer() can still rearm them. If mac80211 tears the BA sessions down we don't want to rearm the timers at a later time so avoid this possibility. Signed-off-by: Luis R. Rodriguez --- Figure I'd start reviewing mod_timer()/mod_timer_pending() as no one caught on. Likely not an issue on mac80211 but I suspect drivers will all be poo. net/mac80211/agg-rx.c | 2 +- net/mac80211/agg-tx.c | 2 +- net/mac80211/rx.c | 4 ++-- 3 files changed, 4 insertions(+), 4 deletions(-) diff --git a/net/mac80211/agg-rx.c b/net/mac80211/agg-rx.c index 31bf258..47d7468 100644 --- a/net/mac80211/agg-rx.c +++ b/net/mac80211/agg-rx.c @@ -153,7 +153,7 @@ static void sta_rx_agg_session_timer_expired(unsigned long data) timeout = tid_rx->last_rx + TU_TO_JIFFIES(tid_rx->timeout); if (time_is_after_jiffies(timeout)) { - mod_timer(&tid_rx->session_timer, timeout); + mod_timer_pending(&tid_rx->session_timer, timeout); rcu_read_unlock(); return; } diff --git a/net/mac80211/agg-tx.c b/net/mac80211/agg-tx.c index 13b7683..b15b629 100644 --- a/net/mac80211/agg-tx.c +++ b/net/mac80211/agg-tx.c @@ -488,7 +488,7 @@ static void sta_tx_agg_session_timer_expired(unsigned long data) timeout = tid_tx->last_tx + TU_TO_JIFFIES(tid_tx->timeout); if (time_is_after_jiffies(timeout)) { - mod_timer(&tid_tx->session_timer, timeout); + mod_timer_pending(&tid_tx->session_timer, timeout); rcu_read_unlock(); return; } diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index 5b4492a..0b81653 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -2216,8 +2216,8 @@ ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames) /* reset session timer */ if (tid_agg_rx->timeout) - mod_timer(&tid_agg_rx->session_timer, - TU_TO_EXP_TIME(tid_agg_rx->timeout)); + mod_timer_pending(&tid_agg_rx->session_timer, + TU_TO_EXP_TIME(tid_agg_rx->timeout)); spin_lock(&tid_agg_rx->reorder_lock); /* release stored frames up to start of BAR */ -- 1.7.10.4