Commit-ID: e37cee133c72c9529f74a20d9b7eb3b6dfb928b5
Gitweb: http://git.kernel.org/tip/e37cee133c72c9529f74a20d9b7eb3b6dfb928b5
Author: Michael S. Tsirkin [off-list ref]
AuthorDate: Thu, 28 Jan 2016 19:02:37 +0200
Committer: Ingo Molnar [off-list ref]
CommitDate: Fri, 29 Jan 2016 09:40:10 +0100
locking/x86: Drop a comment left over from X86_OOSTORE
The comment about wmb being non-NOP to deal with non-Intel CPUs
is a left over from before the following commit:
09df7c4c8097 ("x86: Remove CONFIG_X86_OOSTORE")
It makes no sense now: in particular, wmb() is not a NOP even for
regular Intel CPUs because of weird use-cases e.g. dealing with
WC memory.
Drop this comment.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrey Konovalov <redacted>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <redacted>
Cc: Brian Gerst <redacted>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Davidlohr Bueso <redacted>
Cc: Denys Vlasenko <redacted>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <redacted>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <redacted>
Cc: virtualization <redacted>
Link: http://lkml.kernel.org/r/1453921746-16178-3-git-send-email-mst@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
arch/x86/include/asm/barrier.h | 4 ----
1 file changed, 4 deletions(-)
diff --git a/arch/x86/include/asm/barrier.h b/arch/x86/include/asm/barrier.h
index a65bdb1..a291745 100644
--- a/arch/x86/include/asm/barrier.h
+++ b/arch/x86/include/asm/barrier.h
@@ -11,10 +11,6 @@
*/
#ifdef CONFIG_X86_32
-/*
- * Some non-Intel clones support out of order store. wmb() ceases to be a
- * nop for these.
- */
#define mb() asm volatile(ALTERNATIVE("lock; addl $0,0(%%esp)", "mfence", \
X86_FEATURE_XMM2) ::: "memory", "cc")
#define rmb() asm volatile(ALTERNATIVE("lock; addl $0,0(%%esp)", "lfence", \