Function slab_alloc_item

freebsd/vm/uma_core.c:3758–3785

}

static void *
slab_alloc_item(uma_keg_t keg, uma_slab_t slab)
{
	uma_domain_t dom;
	void *item;
	int freei;

	KEG_LOCK_ASSERT(keg, slab->us_domain);

	dom = &keg->uk_domain[slab->us_domain];
	freei = BIT_FFS(keg->uk_ipers, &slab->us_free) - 1;
	BIT_CLR(keg->uk_ipers, freei, &slab->us_free);
	item = slab_item(slab, keg, freei);
	slab->us_freecount--;
	dom->ud_free_items--;

	/*
	 * Move this slab to the full list.  It must be on the partial list, so
	 * we do not need to update the free slab count.  In particular,
	 * keg_fetch_slab() always returns slabs on the partial list.
	 */
	if (slab->us_freecount == 0) {
		LIST_REMOVE(slab, us_link);
		LIST_INSERT_HEAD(&dom->ud_full_slab, slab, us_link);
	}

	return (item);
}

static int
zone_import(void *arg, void **bucket, int max, int domain, int flags)