Re: [PATCH v5 4/5] x86: use mb() around clflush

[Peter Zijlstra]

On Thu, Jan 28, 2016 at 07:02:51PM +0200, Michael S. Tsirkin wrote:
> commit f8e617f4582995f7c25ef25b4167213120ad122b ("sched/idle/x86:
> Optimize unnecessary mwait_idle() resched IPIs") adds
> memory barriers around clflush, but this seems wrong
> for UP since barrier() has no effect on clflush.
> We really want mfence so switch to mb() instead.
> 
> Cc: Mike Galbraith <bitbucket@xxxxxxxxx>
> Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>

Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>