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[tip:locking/core] locking/x86: Drop a comment left over from X86_OOSTORE

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Commit-ID:  e37cee133c72c9529f74a20d9b7eb3b6dfb928b5
Gitweb:     http://git.kernel.org/tip/e37cee133c72c9529f74a20d9b7eb3b6dfb928b5
Author:     Michael S. Tsirkin <mst@redhat.com>
AuthorDate: Thu, 28 Jan 2016 19:02:37 +0200
Committer:  Ingo Molnar <mingo@kernel.org>
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 <andreyknvl@google.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: virtualization <virtualization@lists.linux-foundation.org>
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", \

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[PATCH v5 0/5] x86: faster smp_mb()+documentation tweaks "Michael S. Tsirkin" <mst@redhat.com> - 2016-01-28 18:10 +0100
  [PATCH v5 5/5] x86: drop mfence in favor of lock+addl "Michael S. Tsirkin" <mst@redhat.com> - 2016-01-28 18:10 +0100
  [PATCH v5 4/5] x86: use mb() around clflush "Michael S. Tsirkin" <mst@redhat.com> - 2016-01-28 18:10 +0100
    Re: [PATCH v5 4/5] x86: use mb() around clflush Peter Zijlstra <peterz@infradead.org> - 2016-01-28 19:30 +0100
    [tip:locking/core] locking/x86: Use mb() around clflush() "tip-bot for Michael S. Tsirkin" <tipbot@zytor.com> - 2016-01-29 12:40 +0100
  [PATCH v5 1/5] x86: add cc clobber for addl "Michael S. Tsirkin" <mst@redhat.com> - 2016-01-28 18:10 +0100
    [tip:locking/core] locking/x86: Add cc clobber for ADDL "tip-bot for Michael S. Tsirkin" <tipbot@zytor.com> - 2016-01-29 12:40 +0100
  [PATCH v5 2/5] x86: drop a comment left over from X86_OOSTORE "Michael S. Tsirkin" <mst@redhat.com> - 2016-01-28 18:10 +0100
    [tip:locking/core] locking/x86:   Drop a comment left over from X86_OOSTORE "tip-bot for Michael S. Tsirkin" <tipbot@zytor.com> - 2016-01-29 12:40 +0100

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