atomic_fetchadd_int
if (atomic_fetchadd_int(&e->refcnt, -1) == 1)
if (atomic_fetchadd_int(&e->refcnt, 1) == 1) /* 0 -> 1 transition */
int atomic_fetchadd_int(volatile int *p, int v);
xid = atomic_fetchadd_int(&nlm_xid, 1);
xid = atomic_fetchadd_int(&nlm_xid, 1);
xid = atomic_fetchadd_int(&nlm_xid, 1);
xid = atomic_fetchadd_int(&nlm_xid, 1);