[mirror_ubuntu-zesty-kernel.git] / tools / virtio / asm / barrier.h

#if defined(__i386__) || defined(__x86_64__)
#define barrier() asm volatile("" ::: "memory")
#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 mb() abort()
# define rmb() abort()
# define wmb() abort()
#else
#error Please fill in barrier macros
#endif
Commit	Line	Data
61d0b5a4 RR	1	#if defined(__i386__) \|\| defined(__x86_64__)
61d0b5a4 RR	2	#define barrier() asm volatile("" ::: "memory")
a7c49033 MT	3	#define virt_mb() __sync_synchronize()
	4	#define virt_rmb() barrier()
	5	#define virt_wmb() barrier()
	6	/* Atomic store should be enough, but gcc generates worse code in that case. */
	7	#define virt_store_mb(var, value) do { \
	8	typeof(var) virt_store_mb_value = (value); \
	9	__atomic_exchange(&(var), &virt_store_mb_value, &virt_store_mb_value, \
	10	__ATOMIC_SEQ_CST); \
	11	barrier(); \
	12	} while (0);
61d0b5a4	13	/* Weak barriers should be used. If not - it's a bug */
a7c49033 MT	14	# define mb() abort()
	15	# define rmb() abort()
	16	# define wmb() abort()
61d0b5a4 RR	17	#else
	18	#error Please fill in barrier macros
	19	#endif
	20