memcontrol.c

		return 1;

	mem->info.nodeinfo[node] = pn;
	memset(pn, 0, sizeof(*pn));

	for (zone = 0; zone < MAX_NR_ZONES; zone++) {
		mz = &pn->zoneinfo[zone];
		INIT_LIST_HEAD(&mz->active_list);
		INIT_LIST_HEAD(&mz->inactive_list);
		spin_lock_init(&mz->lru_lock);
	}
	return 0;
}

static void free_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node)
{
	kfree(mem->info.nodeinfo[node]);
}

static struct cgroup_subsys_state *
mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont)
{
	struct mem_cgroup *mem;
	int node;

	if (unlikely((cont->parent) == NULL)) {
		mem = &init_mem_cgroup;
		init_mm.mem_cgroup = mem;
	} else
		mem = kzalloc(sizeof(struct mem_cgroup), GFP_KERNEL);

	if (mem == NULL)
		return ERR_PTR(-ENOMEM);

	res_counter_init(&mem->res);

	memset(&mem->info, 0, sizeof(mem->info));

	for_each_node_state(node, N_POSSIBLE)
		if (alloc_mem_cgroup_per_zone_info(mem, node))
			goto free_out;

	return &mem->css;
free_out:
	for_each_node_state(node, N_POSSIBLE)
		free_mem_cgroup_per_zone_info(mem, node);
	if (cont->parent != NULL)
		kfree(mem);
	return ERR_PTR(-ENOMEM);
}

static void mem_cgroup_pre_destroy(struct cgroup_subsys *ss,
					struct cgroup *cont)
{
	struct mem_cgroup *mem = mem_cgroup_from_cont(cont);
	mem_cgroup_force_empty(mem);
}

static void mem_cgroup_destroy(struct cgroup_subsys *ss,
				struct cgroup *cont)
{
	int node;
	struct mem_cgroup *mem = mem_cgroup_from_cont(cont);

	for_each_node_state(node, N_POSSIBLE)
		free_mem_cgroup_per_zone_info(mem, node);

	kfree(mem_cgroup_from_cont(cont));
}

static int mem_cgroup_populate(struct cgroup_subsys *ss,
				struct cgroup *cont)
{
	return cgroup_add_files(cont, ss, mem_cgroup_files,
					ARRAY_SIZE(mem_cgroup_files));
}

static void mem_cgroup_move_task(struct cgroup_subsys *ss,
				struct cgroup *cont,
				struct cgroup *old_cont,
				struct task_struct *p)
{
	struct mm_struct *mm;
	struct mem_cgroup *mem, *old_mem;

	mm = get_task_mm(p);
	if (mm == NULL)
		return;

	mem = mem_cgroup_from_cont(cont);
	old_mem = mem_cgroup_from_cont(old_cont);

	if (mem == old_mem)
		goto out;

	/*
	 * Only thread group leaders are allowed to migrate, the mm_struct is
	 * in effect owned by the leader
	 */
	if (p->tgid != p->pid)
		goto out;

	css_get(&mem->css);
	rcu_assign_pointer(mm->mem_cgroup, mem);
	css_put(&old_mem->css);

out:
	mmput(mm);
}

struct cgroup_subsys mem_cgroup_subsys = {
	.name = "memory",
	.subsys_id = mem_cgroup_subsys_id,
	.create = mem_cgroup_create,
	.pre_destroy = mem_cgroup_pre_destroy,
	.destroy = mem_cgroup_destroy,
	.populate = mem_cgroup_populate,
	.attach = mem_cgroup_move_task,
	.early_init = 0,
};