Function thread_reap_domain

freebsd/kern/kern_thread.c:580–646

* Reap zombies from passed domain. */

 * Reap zombies from passed domain.
 */
static void
thread_reap_domain(struct thread_domain_data *tdd)
{
	struct thread *itd, *ntd;
	struct tidbatch tidbatch;
	struct credbatch credbatch;
	int tdcount;
	struct plimit *lim;
	int limcount;

	/*
	 * Reading upfront is pessimal if followed by concurrent atomic_swap,
	 * but most of the time the list is empty.
	 */
	if (tdd->tdd_zombies == NULL)
		return;

	itd = (struct thread *)atomic_swap_ptr((uintptr_t *)&tdd->tdd_zombies,
	    (uintptr_t)NULL);
	if (itd == NULL)
		return;

	/*
	 * Multiple CPUs can get here, the race is fine as ticks is only
	 * advisory.
	 */
	tdd->tdd_reapticks = ticks;

	tidbatch_prep(&tidbatch);
	credbatch_prep(&credbatch);
	tdcount = 0;
	lim = NULL;
	limcount = 0;

	while (itd != NULL) {
		ntd = itd->td_zombie;
		EVENTHANDLER_DIRECT_INVOKE(thread_dtor, itd);
		tidbatch_add(&tidbatch, itd);
		credbatch_add(&credbatch, itd);
		MPASS(itd->td_limit != NULL);
		if (lim != itd->td_limit) {
			if (limcount != 0) {
				lim_freen(lim, limcount);
				limcount = 0;
			}
		}
		lim = itd->td_limit;
		limcount++;
		thread_free_batched(itd);
		tidbatch_process(&tidbatch);
		credbatch_process(&credbatch);
		tdcount++;
		if (tdcount == 32) {
			thread_count_sub(tdcount);
			tdcount = 0;
		}
		itd = ntd;
	}