raw_atomic_cmpxchg
while (raw_atomic_cmpxchg(&__nmi_ipi_lock, 0, 1) == 1) {
while (raw_atomic_cmpxchg(&__nmi_ipi_lock, 0, 1) == 1)
r = raw_atomic_cmpxchg(v, o, new);
return raw_atomic_cmpxchg(v, old, new);
return raw_atomic_cmpxchg(v, old, new);