static inline int ldsem_cmpxchg(long *old, long new, struct ld_semaphore *sem)
{
	long tmp = *old;
	*old = atomic_long_cmpxchg(&sem->count, *old, new);
	return *old == tmp;
}
The program contains a code sequence that can run concurrently with other code, and the code sequence requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence that is operating concurrently.