linux-imx

/*

 * Copyright (C) 2017 Red Hat. All rights reserved.

 *

 * This file is released under the GPL.

 */

​

#include "dm-cache-background-tracker.h"

​

/*----------------------------------------------------------------*/

​

#define DM_MSG_PREFIX "dm-background-tracker"

​

struct bt_work {

    struct list_head list;

    struct rb_node node;

    struct policy_work work;

};

​

struct background_tracker {

    unsigned max_work;

    atomic_t pending_promotes;

    atomic_t pending_writebacks;

    atomic_t pending_demotes;

​

    struct list_head issued;

    struct list_head queued;

    struct rb_root pending;

​

    struct kmem_cache *work_cache;

};

​

struct background_tracker *btracker_create(unsigned max_work)

{

    struct background_tracker *b = kmalloc(sizeof(*b), GFP_KERNEL);

​

    if (!b) {

        DMERR("couldn't create background_tracker");

        return NULL;

    }

​

    b->max_work = max_work;

    atomic_set(&b->pending_promotes, 0);

    atomic_set(&b->pending_writebacks, 0);

    atomic_set(&b->pending_demotes, 0);

​

    INIT_LIST_HEAD(&b->issued);

    INIT_LIST_HEAD(&b->queued);

​

    b->pending = RB_ROOT;

    b->work_cache = KMEM_CACHE(bt_work, 0);

    if (!b->work_cache) {

        DMERR("couldn't create mempool for background work items");

        kfree(b);

        b = NULL;

    }

​

    return b;

}

EXPORT_SYMBOL_GPL(btracker_create);

​

void btracker_destroy(struct background_tracker *b)

{

    kmem_cache_destroy(b->work_cache);