Fix barrier for sh4a
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/arch/arch-sh.h b/arch/arch-sh.h
index 23e6ca0..08c5fb3 100644
--- a/arch/arch-sh.h
+++ b/arch/arch-sh.h
@@ -21,7 +21,14 @@
#endif
#define nop __asm__ __volatile__ ("nop": : :"memory")
-#define read_barrier() __asm__ __volatile__ (" " : : : "memory")
-#define write_barrier() __asm__ __volatile__ (" " : : : "memory")
+
+#if defined(__SH4A__)
+#define mb() __asm__ __volatile__ ("synco": : :"memory")
+#else
+#define mb() __asm__ __volatile__ (" " : : : "memory")
+#endif
+
+#define read_barrier() mb()
+#define write_barrier() mb()
#endif