tools/virtio: use virt_xxx barriers

[cascardo/linux.git] / tools / virtio / asm / barrier.h

diff --git a/tools/virtio/asm/barrier.h b/tools/virtio/asm/barrier.h
index 26b7926..ba34f9e 100644 (file)
--- a/tools/virtio/asm/barrier.h
+++ b/tools/virtio/asm/barrier.h
@@ -1,15 +1,19 @@
 #if defined(__i386__) || defined(__x86_64__)
 #define barrier() asm volatile("" ::: "memory")
-#define mb() __sync_synchronize()
-
-#define smp_mb()       mb()
-# define dma_rmb()     barrier()
-# define dma_wmb()     barrier()
-# define smp_rmb()     barrier()
-# define smp_wmb()     barrier()
+#define virt_mb() __sync_synchronize()
+#define virt_rmb() barrier()
+#define virt_wmb() barrier()
+/* Atomic store should be enough, but gcc generates worse code in that case. */
+#define virt_store_mb(var, value)  do { \
+       typeof(var) virt_store_mb_value = (value); \
+       __atomic_exchange(&(var), &virt_store_mb_value, &virt_store_mb_value, \
+                         __ATOMIC_SEQ_CST); \
+       barrier(); \
+} while (0);
 /* Weak barriers should be used. If not - it's a bug */
-# define rmb() abort()
-# define wmb() abort()
+# define mb() abort()
+# define rmb() abort()
+# define wmb() abort()
 #else
 #error Please fill in barrier macros
 #endif