From d73d68dc49e09143e8e3bef10670a021c26ec4a5 Mon Sep 17 00:00:00 2001 From: Youquan Song Date: Fri, 26 Oct 2012 12:26:59 +0200 Subject: [PATCH] cpuidle: Set residency to 0 if target Cstate not enter When cpuidle governor choose a C-state to enter for idle CPU, but it notice that there is tasks request to be executed. So the idle CPU will not really enter the target C-state and go to run task. In this situation, it will use the residency of previous really entered target C-states. Obviously, it is not reasonable. So, this patch fix it by set the target C-state residency to 0. Signed-off-by: Rik van Riel Signed-off-by: Youquan Song Signed-off-by: Rafael J. Wysocki --- drivers/cpuidle/cpuidle.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index f4b8fc50c0f2..ce4cac706dd1 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -144,6 +144,10 @@ int cpuidle_idle_call(void) /* ask the governor for the next state */ next_state = cpuidle_curr_governor->select(drv, dev); if (need_resched()) { + dev->last_residency = 0; + /* give the governor an opportunity to reflect on the outcome */ + if (cpuidle_curr_governor->reflect) + cpuidle_curr_governor->reflect(dev, next_state); local_irq_enable(); return 0; }