* failure case.
*/
#define CMPXCHG_LOOP(CODE, SUCCESS) do { \
+ int retry = 100; \
struct lockref old; \
BUILD_BUG_ON(sizeof(old) != 8); \
old.lock_count = READ_ONCE(lockref->lock_count); \
if (likely(old.lock_count == prev.lock_count)) { \
SUCCESS; \
} \
+ if (!--retry) \
+ break; \
cpu_relax(); \
} \
} while (0)