Re: [PATCH v5 4/5] x86: use mb() around clflush
From: Peter Zijlstra <peterz@infradead.org>
Date: 2016-01-28 18:25:41
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 <redacted>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>