__atomic_op_fence 27 include/linux/atomic-fallback.h __atomic_op_fence(xchg, __VA_ARGS__) __atomic_op_fence 50 include/linux/atomic-fallback.h __atomic_op_fence(cmpxchg, __VA_ARGS__) __atomic_op_fence 73 include/linux/atomic-fallback.h __atomic_op_fence(cmpxchg64, __VA_ARGS__)