[Xen-changelog] [xen-unstable] [HVM] Remove unnecessary write barriers

[Xen patchbot-unstable <patchbot-unstable@xxxxxxxxxxxxxxxxxxx>]

# HG changeset patch
# User Tim Deegan <Tim.Deegan@xxxxxxxxxxxxx>
# Date 1168361356 0
# Node ID de6b5a76d680057c7793561c40a9285c613065d1
# Parent  3040ba0f2d3d8659ffadda1f5b599a7ca60f8b53
[HVM] Remove unnecessary write barriers
Using a volatile pointer saves us from the compier reordering these
writes, and the processor won't let them appear out of order.
Signed-off-by: Tim Deegan <Tim.Deegan@xxxxxxxxxxxxx>
---
 xen/arch/x86/mm/shadow/multi.c |    2 --
 1 files changed, 2 deletions(-)

diff -r 3040ba0f2d3d -r de6b5a76d680 xen/arch/x86/mm/shadow/multi.c
--- a/xen/arch/x86/mm/shadow/multi.c    Tue Jan 09 13:24:45 2007 +0000
+++ b/xen/arch/x86/mm/shadow/multi.c    Tue Jan 09 16:49:16 2007 +0000
@@ -851,9 +851,7 @@ static inline void safe_write_entry(void
      * then writing the high word before the low word. */
     BUILD_BUG_ON(sizeof (shadow_l1e_t) != 2 * sizeof (unsigned long));
     d[0] = 0;
-    wmb();
     d[1] = s[1];
-    wmb();
     d[0] = s[0];
 #else
     /* In 32-bit and 64-bit, sizeof(pte) == sizeof(ulong) == 1 word,

_______________________________________________
Xen-changelog mailing list
Xen-changelog@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-changelog