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SubjectRe: [PATCH v3 1/7] locking/pvqspinlock: Unconditional PV kick with _Q_SLOW_VAL
On Wed, Jul 22, 2015 at 04:12:36PM -0400, Waiman Long wrote:
> The smp_store_release() is not a full barrier. In order to avoid missed
> wakeup, we may need to add memory barrier around locked and cpu state
> variables adding to complexity. As the chance of spurious wakeup is very
> low, it is easier and safer to just do an unconditional kick at unlock
> time.

This needs to better spell out the race; my still sleeping brain doesn't
want to co-operate and its generally better to spell out these things
anyway.


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