Re: [PATCH V5] x86 spinlock: Fix memory corruption on completing completions

Oleg Nesterov
2015-02-15T20:31:59Z

On 02/15, Raghavendra K T wrote:
>
> * Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> [2015-02-15 11:25:44]:
>
> Resending the V5 with smp_mb__after_atomic() change without bumping up
> revision

Reviewed-by: Oleg Nesterov <oleg@redhat.com>

Of course, this needs the acks from maintainers. And I agree that SLOWPATH
in .head makes xadd() in unlock() unavoidable. However I do not see how we
can avoid the locked inc if we want to eliminate read-after-unlock.