linux-imx

/*

 * Copyright (c) 2013 Red Hat, Inc. and Parallels Inc. All rights reserved.

 * Authors: David Chinner and Glauber Costa

 *

 * Generic LRU infrastructure

 */

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/mm.h>

#include <linux/list_lru.h>

#include <linux/slab.h>

#include <linux/mutex.h>

#include <linux/memcontrol.h>

​

#ifdef CONFIG_MEMCG_KMEM

static LIST_HEAD(list_lrus);

static DEFINE_MUTEX(list_lrus_mutex);

​

static void list_lru_register(struct list_lru *lru)

{

    mutex_lock(&list_lrus_mutex);

    list_add(&lru->list, &list_lrus);

    mutex_unlock(&list_lrus_mutex);

}

​

static void list_lru_unregister(struct list_lru *lru)

{

    mutex_lock(&list_lrus_mutex);

    list_del(&lru->list);

    mutex_unlock(&list_lrus_mutex);

}

​

static int lru_shrinker_id(struct list_lru *lru)

{

    return lru->shrinker_id;

}

​

static inline bool list_lru_memcg_aware(struct list_lru *lru)

{

    /*

     * This needs node 0 to be always present, even

     * in the systems supporting sparse numa ids.

     */

    return !!lru->node[0].memcg_lrus;

}

​

static inline struct list_lru_one *

list_lru_from_memcg_idx(struct list_lru_node *nlru, int idx)

{

    struct list_lru_memcg *memcg_lrus;

    /*

     * Either lock or RCU protects the array of per cgroup lists

     * from relocation (see memcg_update_list_lru_node).

     */

    memcg_lrus = rcu_dereference_check(nlru->memcg_lrus,

                       lockdep_is_held(&nlru->lock));

    if (memcg_lrus && idx >= 0)

        return memcg_lrus->lru[idx];

    return &nlru->lru;

}

​

static __always_inline struct mem_cgroup *mem_cgroup_from_kmem(void *ptr)

{