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SubjectRe: [PATCH tip/core/rcu 21/21] drivers/vhost: Remove now-redundant read_barrier_depends()
On Tue, Dec 05, 2017 at 09:51:48PM +0200, Michael S. Tsirkin wrote:
> > > WRITE_ONCE(obj->val, 1);
> > > smp_wmb();
> > > WRITE_ONCE(*foo, obj);
> >
> > I believe Peter was instead suggesting:
> >
> > WRITE_ONCE(obj->val, 1);
> > smp_store_release(foo, obj);
>
> Isn't that more expensive though?

Depends on the architecture. The only architecture where it is more
expensive and people actually still care about is ARM I think.

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