OSSpinLockTry

gistfile1.txt

/*
 * void
 * OSSpinLockUnlock(p)
 *      int *p;
 *
 * Unlock the lock pointed to by p.
 */

LEAF(_OSSpinLockUnlock, 0)
LEAF(_IOSpinUnlock, 0)
LEAF(_ev_unlock, 0)
        movl            $0, (%rdi)
END(_OSSpinLockUnlock)


/*
 * int
 * OSSpinLockTry(p)
 *      int *p;
 *
 * Try to lock p.  Return zero if not successful.
 */

LEAF(_OSSpinLockTry, 0)
LEAF(_IOTrySpinLock, 0)
LEAF(_ev_try_lock, 0)
        xorl            %eax, %eax
        orl             $-1, %edx
        lock
        cmpxchgl        %edx, (%rdi)
        setz            %dl
        movzbl          %dl, %eax
END(_OSSpinLockTry)