[PATCH v2 3/3] x86: tweak the comment about use of wmb for IO

From	"Michael S. Tsirkin" <mst@redhat.com>
Newsgroups	linux.kernel
Subject	[PATCH v2 3/3] x86: tweak the comment about use of wmb for IO
Date	2016-01-12 23:20 +0100
Message-ID	<qQfse-7eN-25@gated-at.bofh.it> (permalink)
References	<qQfsd-7eN-3@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On x86, we *do* still use the non-nop rmb/wmb for IO barriers, but even
that is generally questionable.

Leave them around as historial unless somebody can point to a case where
they care about the performance, but tweak the comment so people
don't think they are strictly required in all cases.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 arch/x86/include/asm/barrier.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/barrier.h b/arch/x86/include/asm/barrier.h
index eb220b8..924cd44 100644
--- a/arch/x86/include/asm/barrier.h
+++ b/arch/x86/include/asm/barrier.h
@@ -6,7 +6,7 @@
 
 /*
  * Force strict CPU ordering.
- * And yes, this is required on UP too when we're talking
+ * And yes, this might be required on UP too when we're talking
  * to devices.
  */
 
-- 
MST

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[PATCH v2 3/3] x86: tweak the comment about use of wmb for IO "Michael S. Tsirkin" <mst@redhat.com> - 2016-01-12 23:20 +0100

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