From: Vitaly Wool Date: Thu, 6 Sep 2012 14:06:52 +0000 (+0200) Subject: rfkill: prevent unnecessary event generation X-Git-Tag: v3.7-rc1~145^2~30^2~48^2~1 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=eab48345c2b2d791159aaac4a77000baa8dbc1ae;p=profile%2Fivi%2Fkernel-adaptation-intel-automotive.git rfkill: prevent unnecessary event generation Prevent unnecessary rfkill event generation when the state has not actually changed. These events have to be delivered to relevant userspace processes, causing these processes to wake up and do something while they could as well have slept. This obviously results in more CPU usage, longer time-to-sleep-again and therefore higher power consumption. Signed-off-by: Vitaly Wool Signed-off-by: Mykyta Iziumtsev Signed-off-by: Johannes Berg --- diff --git a/net/rfkill/core.c b/net/rfkill/core.c index c275bad..a5c9527 100644 --- a/net/rfkill/core.c +++ b/net/rfkill/core.c @@ -270,6 +270,7 @@ static bool __rfkill_set_hw_state(struct rfkill *rfkill, static void rfkill_set_block(struct rfkill *rfkill, bool blocked) { unsigned long flags; + bool prev, curr; int err; if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP)) @@ -284,6 +285,8 @@ static void rfkill_set_block(struct rfkill *rfkill, bool blocked) rfkill->ops->query(rfkill, rfkill->data); spin_lock_irqsave(&rfkill->lock, flags); + prev = rfkill->state & RFKILL_BLOCK_SW; + if (rfkill->state & RFKILL_BLOCK_SW) rfkill->state |= RFKILL_BLOCK_SW_PREV; else @@ -313,10 +316,13 @@ static void rfkill_set_block(struct rfkill *rfkill, bool blocked) } rfkill->state &= ~RFKILL_BLOCK_SW_SETCALL; rfkill->state &= ~RFKILL_BLOCK_SW_PREV; + curr = rfkill->state & RFKILL_BLOCK_SW; spin_unlock_irqrestore(&rfkill->lock, flags); rfkill_led_trigger_event(rfkill); - rfkill_event(rfkill); + + if (prev != curr) + rfkill_event(rfkill); } #ifdef CONFIG_RFKILL_INPUT