Re: [PATCH v2] cpuidle: coupled: abort idle if pokes are pending

[Colin Cross]

On Thu, Aug 29, 2013 at 1:28 PM, Rafael J. Wysocki <rjw@xxxxxxx> wrote:
> On Wednesday, August 28, 2013 06:41:47 PM Colin Cross wrote:
>> Joseph Lo <josephl@xxxxxxxxxx> reported a lockup on Tegra20 caused
>> by a race condition in coupled cpuidle.  When two or more cpus
>> enter idle at the same time, the first cpus to arrive may go to the
>> ready loop without processing pending pokes from the last cpu to
>> arrive.
>>
>> This patch adds a check for pending pokes once all cpus have been
>> synchronized in the ready loop and resets the coupled state and
>> retries if any cpus failed to handle their pending poke.
>>
>> Retrying on all cpus may trigger the same issue again, so this patch
>> also adds a check to ensure that each cpu has received at least one
>> poke between when it enters the waiting loop and when it moves on to
>> the ready loop.
>>
>> Reported-by: Joseph Lo <josephl@xxxxxxxxxx>
>> Tested-by: Stephen Warren <swarren@xxxxxxxxxx>
>> Tested-by: Joseph Lo <josephl@xxxxxxxxxx>
>> Signed-off-by: Colin Cross <ccross@xxxxxxxxxxx>
>
> Still stable material I suppose?

Yes please
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