KTHREAD_IS_PARKED_MASK
atomic_andnot(KTHREAD_IS_PARKED_MASK, &task->kthread_flags);
if ((atomic_fetch_andnot(KTHREAD_IS_PARKED_MASK, &task->kthread_flags) &
KTHREAD_IS_PARKED_MASK) != 0)
while ((atomic_fetch_or(KTHREAD_IS_PARKED_MASK,
&task->kthread_flags) & KTHREAD_IS_PARKED_MASK) == 0)