Function vm_swapout_object_deactivate

freebsd/vm/vm_swapout.c:206–248

* vm_swapout_object_deactivate * * Deactivate enough pages to satisfy the inactive target * requirements. * * The object and map must be locked. */

 *	The object and map must be locked.
 */
static void
vm_swapout_object_deactivate(pmap_t pmap, vm_object_t first_object,
    long desired)
{
	vm_object_t backing_object, object;
	vm_page_t m;
	bool unmap;

	VM_OBJECT_ASSERT_LOCKED(first_object);
	if ((first_object->flags & OBJ_FICTITIOUS) != 0)
		return;
	for (object = first_object;; object = backing_object) {
		if (pmap_resident_count(pmap) <= desired)
			goto unlock_return;
		VM_OBJECT_ASSERT_LOCKED(object);
		if ((object->flags & OBJ_UNMANAGED) != 0 ||
		    blockcount_read(&object->paging_in_progress) > 0)
			goto unlock_return;

		unmap = true;
		if (object->shadow_count > 1)
			unmap = false;

		/*
		 * Scan the object's entire memory queue.
		 */
		TAILQ_FOREACH(m, &object->memq, listq) {
			if (pmap_resident_count(pmap) <= desired)
				goto unlock_return;
			if (should_yield())
				goto unlock_return;
			vm_swapout_object_deactivate_page(pmap, m, unmap);
		}
		if ((backing_object = object->backing_object) == NULL)
			goto unlock_return;
		VM_OBJECT_RLOCK(backing_object);
		if (object != first_object)
			VM_OBJECT_RUNLOCK(object);
	}
unlock_return:
	if (object != first_object)
		VM_OBJECT_RUNLOCK(object);
}

/*
 * deactivate some number of pages in a map, try to do it fairly, but