[PATCH 28/34] x86: define __smp_xxX

Michael S. Tsirkin
2015-12-30T21:52:26Z

This defines __smp_XXX barriers for x86,
for use by virtualization.

smp_XXX barriers are removed as they are
defined correctly by asm-generic/barriers.h

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
arch/x86/include/asm/barrier.h | 31 ++++++++++++-------------------
1 file changed, 12 insertions(+), 19 deletions(-)

diff --git a/arch/x86/include/asm/barrier.h b/arch/x86/include/asm/barrier.h
index cc4c2a7..a584e1c 100644
--- a/arch/x86/include/asm/barrier.h
+++ b/arch/x86/include/asm/barrier.h
@@ -31,17 +31,10 @@
#endif
#define dma_wmb() barrier()

-#ifdef CONFIG_SMP
-#define smp_mb() mb()
-#define smp_rmb() dma_rmb()
-#define smp_wmb() barrier()
-#define smp_store_mb(var, value) do { (void)xchg(&var, value); } while (0)
-#else /* !SMP */
-#define smp_mb() barrier()
-#define smp_rmb() barrier()
-#define smp_wmb() barrier()
-#define smp_store_mb(var, value) do { WRITE_ONCE(var, value); barrier(); } while (0)
-#endif /* SMP */
+#define __smp_mb() mb()
+#define __smp_rmb() dma_rmb()
+#define __smp_wmb() barrier()
+#define __smp_store_mb(var, value) do { (void)xchg(&var, value); } while (0)

#if defined(CONFIG_X86_PPRO_FENCE)

@@ -50,31 +43,31 @@
* model and we should fall back to full barriers.
*/

-#define smp_store_release(p, v) \
+#define __smp_store_release(p, v) \
do { \
compiletime_assert_atomic_type(*p); \
- smp_mb(); \
+ __smp_mb(); \
WRITE_ONCE(*p, v); \
} while (0)

-#define smp_load_acquire(p) \
+#define __smp_load_acquire(p) \
({ \
typeof(*p) ___p1 = READ_ONCE(*p); \
compiletime_assert_atomic_type(*p); \
- smp_mb(); \
+ __smp_mb(); \
___p1; \
})

#else /* regular x86 TSO memory ordering */

-#define smp_store_release(p, v) \
+#define __smp_store_release(p, v) \
do { \
compiletime_assert_atomic_type(*p); \
barrier(); \
WRITE_ONCE(*p, v); \
} while (0)

-#define smp_load_acquire(p) \
+#define __smp_load_acquire(p) \
({ \
typeof(*p) ___p1 = READ_ONCE(*p); \
compiletime_assert_atomic_type(*p); \
@@ -85,8 +78,8 @@ do { \
#endif

/* Atomic operations are already serializing on x86 */
-#define smp_mb__before_atomic() barrier()
-#define smp_mb__after_atomic() barrier()
+#define __smp_mb__before_atomic() barrier()
+#define __smp_mb__after_atomic() barrier()

#include <asm-generic/barrier.h>

--
MST