Re: [PATCH] CPUidle: always return with interrupts enabled

From: Rafael J. Wysocki
Date: Wed Sep 30 2009 - 17:20:49 EST


On Wednesday 30 September 2009, Kevin Hilman wrote:
> In the case where cpuidle_idle_call() returns before changing state
> due to a need_resched(), it was returning with IRQs disabled.
>
> This patch ensures IRQs are (re)enabled before returning.

Venki, any comments on this?

> Reported-by: Hemanth V <hemanthv@xxxxxx>
> Signed-off-by: Kevin Hilman <khilman@xxxxxxxxxxxxxxxxxxx>
> ---
> drivers/cpuidle/cpuidle.c | 5 ++++-
> 1 files changed, 4 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
> index ad41f19..12fdd39 100644
> --- a/drivers/cpuidle/cpuidle.c
> +++ b/drivers/cpuidle/cpuidle.c
> @@ -76,8 +76,11 @@ static void cpuidle_idle_call(void)
> #endif
> /* ask the governor for the next state */
> next_state = cpuidle_curr_governor->select(dev);
> - if (need_resched())
> + if (need_resched()) {
> + local_irq_enable();
> return;
> + }
> +
> target_state = &dev->states[next_state];
>
> /* enter the state and update stats */

Best,
Rafael
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