From 1ddc286731134ad52a74b6956d9bc2a4369219a8 Mon Sep 17 00:00:00 2001 From: Rajkumar Manoharan Date: Tue, 3 May 2011 17:03:59 +0530 Subject: [PATCH] mac80211: Postpond ps timer if tx is stopped by others Whenever the driver's queue depth reaches the max, the queues are stopped by the driver till the driver can accept the frames. At the mean time dynamic_ps_timer can be expired due to not receiving packet from upper layer which could restart the transmission at the end of ps work. Due to the mismatch with driver state, mac80211 is unneccesarity buffering all the frames till the driver wakes up the queue. Check whether there is no transmit or the tx queues were stopped by some reasons. If any of the queue was stopped, the postpond ps timer and do not restart netif_tx. Signed-off-by: Rajkumar Manoharan Signed-off-by: John W. Linville --- net/mac80211/mlme.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c index 8d752b4..4f6b267 100644 --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -750,6 +750,8 @@ void ieee80211_dynamic_ps_enable_work(struct work_struct *work) dynamic_ps_enable_work); struct ieee80211_sub_if_data *sdata = local->ps_sdata; struct ieee80211_if_managed *ifmgd = &sdata->u.mgd; + unsigned long flags; + int q; /* can only happen when PS was just disabled anyway */ if (!sdata) @@ -758,6 +760,24 @@ void ieee80211_dynamic_ps_enable_work(struct work_struct *work) if (local->hw.conf.flags & IEEE80211_CONF_PS) return; + /* + * transmission can be stopped by others which leads to + * dynamic_ps_timer expiry. Postpond the ps timer if it + * is not the actual idle state. + */ + spin_lock_irqsave(&local->queue_stop_reason_lock, flags); + for (q = 0; q < local->hw.queues; q++) { + if (local->queue_stop_reasons[q]) { + spin_unlock_irqrestore(&local->queue_stop_reason_lock, + flags); + mod_timer(&local->dynamic_ps_timer, jiffies + + msecs_to_jiffies( + local->hw.conf.dynamic_ps_timeout)); + return; + } + } + spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags); + if ((local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK) && (!(ifmgd->flags & IEEE80211_STA_NULLFUNC_ACKED))) { netif_tx_stop_all_queues(sdata->dev); -- 2.7.4