[PATCH 1/1] ARM: ux500:mach-ux500/cpuidle.c spinlock dis-matching
Daniel Lezcano
daniel.lezcano at linaro.org
Sun Jan 6 11:23:26 EST 2013
On 12/28/2012 08:06 AM, steve.zhan wrote:
> Hi Daniel,
Hi Steve,
sorry I missed your email.
>
> I think we must unlock the master spinlock even
> prcmu_gic_decouple function now always return 0.
> Could you give some infos about this?
I agree, that would be cleaner.
AFAICS, your patch does not solve the problem because 'recouple' will be
false if prcmu_gic_decouple fails, so the lock will never be release.
That will be simpler to do:
if (prcmu_gic_decouple()) {
spin_unlock(&master);
goto out;
}
no ?
> Thanks.
>
> diff --git a/arch/arm/mach-ux500/cpuidle.c b/arch/arm/mach-ux500/cpuidle.c
> index b54884bd..b0759ce 100644
> --- a/arch/arm/mach-ux500/cpuidle.c
> +++ b/arch/arm/mach-ux500/cpuidle.c
> @@ -29,6 +29,7 @@ static inline int ux500_enter_idle(struct cpuidle_device *dev,
> {
> int this_cpu = smp_processor_id();
> bool recouple = false;
> + bool locked = false;
>
> clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &this_cpu);
>
> @@ -39,6 +40,8 @@ static inline int ux500_enter_idle(struct cpuidle_device *dev,
> if (!spin_trylock(&master_lock))
> goto wfi;
>
> + locked = true;
> +
> /* decouple the gic from the A9 cores */
> if (prcmu_gic_decouple())
> goto out;
> @@ -76,7 +79,7 @@ static inline int ux500_enter_idle(struct cpuidle_device *dev,
> /* When we switch to retention, the prcmu is in charge
> * of recoupling the gic automatically */
> recouple = false;
> -
> + locked = false;
> spin_unlock(&master_lock);
> }
> wfi:
> @@ -86,7 +89,8 @@ out:
>
> if (recouple) {
> prcmu_gic_recouple();
> - spin_unlock(&master_lock);
> + if (locked)
> + spin_unlock(&master_lock);
> }
>
> clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &this_cpu);
>
>
>
> Steve Zhan
>
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