static void free_slab(struct kmem_cache *s, struct page *page)
{
	if (unlikely(s->flags & SLAB_TYPESAFE_BY_RCU)) {
		call_rcu(&page->rcu_head, rcu_free_slab);
	} else
		__free_slab(s, page);
}
static void free_slab(struct kmem_cache *s, struct page *page)
{
	if (unlikely(s->flags & SLAB_TYPESAFE_BY_RCU)) {
		call_rcu(&page->rcu_head, rcu_free_slab);
	} else
		__free_slab(s, page);
}