Commit d73d68dc authored Oct 26, 2012 by Youquan Song Committed by Rafael J. Wysocki Nov 15, 2012

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 <riel@redhat.com>
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

parent e11538d1

drivers/cpuidle/cpuidle.c

+4 −0

Original line number	Diff line number	Diff line
		@@ -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;
		}