xen: arm: Use dmb for smp barriers

The full power of dsb is not required in this context.

Also change wmb() to be dsb() directly instead of indirectly via mb(), for
clarity.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Tim Deegan <tim@xen.org>

diff --git a/xen/include/asm-arm/system.h b/xen/include/asm-arm/system.h
index e0036249393e38ce13151b5d6b1c0e92384477a9..89c61efd7a221f85ce951bb75cee023ab7adc671 100644 (file)
--- a/xen/include/asm-arm/system.h
+++ b/xen/include/asm-arm/system.h
@@ -18,11 +18,11 @@
 
 #define mb()            dsb()
 #define rmb()           dsb()
-#define wmb()           mb()
+#define wmb()           dsb()
 
-#define smp_mb()        mb()
-#define smp_rmb()       rmb()
-#define smp_wmb()       wmb()
+#define smp_mb()        dmb()
+#define smp_rmb()       dmb()
+#define smp_wmb()       dmb()
 
 #define xchg(ptr,x) \
         ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))