kmemleak-test.c

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/*
 * mm/kmemleak-test.c
 *
 * Copyright (C) 2008 ARM Limited
 * Written by Catalin Marinas <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/list.h>
#include <linux/percpu.h>
#include <linux/fdtable.h>

#include <linux/kmemleak.h>

struct test_node {
    long header[25];
    struct list_head list;
    long footer[25];
};

static LIST_HEAD(test_list);
static DEFINE_PER_CPU(void *, kmemleak_test_pointer);

/*
 * Some very simple testing. This function needs to be extended for
 * proper testing.
 */
static int __init kmemleak_test_init(void)
{
    struct test_node *elem;
    int i;

    printk(KERN_INFO "Kmemleak testing\n");

    /* make some orphan objects */
    pr_info("kmemleak: kmalloc(32) = %p\n", kmalloc(32, GFP_KERNEL));
    pr_info("kmemleak: kmalloc(32) = %p\n", kmalloc(32, GFP_KERNEL));
    pr_info("kmemleak: kmalloc(1024) = %p\n", kmalloc(1024, GFP_KERNEL));
    pr_info("kmemleak: kmalloc(1024) = %p\n", kmalloc(1024, GFP_KERNEL));
    pr_info("kmemleak: kmalloc(2048) = %p\n", kmalloc(2048, GFP_KERNEL));
    pr_info("kmemleak: kmalloc(2048) = %p\n", kmalloc(2048, GFP_KERNEL));
    pr_info("kmemleak: kmalloc(4096) = %p\n", kmalloc(4096, GFP_KERNEL));
    pr_info("kmemleak: kmalloc(4096) = %p\n", kmalloc(4096, GFP_KERNEL));
#ifndef CONFIG_MODULES
    pr_info("kmemleak: kmem_cache_alloc(files_cachep) = %p\n",
        kmem_cache_alloc(files_cachep, GFP_KERNEL));
    pr_info("kmemleak: kmem_cache_alloc(files_cachep) = %p\n",
        kmem_cache_alloc(files_cachep, GFP_KERNEL));
#endif
    pr_info("kmemleak: vmalloc(64) = %p\n", vmalloc(64));
    pr_info("kmemleak: vmalloc(64) = %p\n", vmalloc(64));
    pr_info("kmemleak: vmalloc(64) = %p\n", vmalloc(64));
    pr_info("kmemleak: vmalloc(64) = %p\n", vmalloc(64));
    pr_info("kmemleak: vmalloc(64) = %p\n", vmalloc(64));

    /*
     * Add elements to a list. They should only appear as orphan
     * after the module is removed.
     */
    for (i = 0; i < 10; i++) {
        elem = kzalloc(sizeof(*elem), GFP_KERNEL);
        pr_info("kmemleak: kzalloc(sizeof(*elem)) = %p\n", elem);
        if (!elem)
            return -ENOMEM;
        INIT_LIST_HEAD(&elem->list);
        list_add_tail(&elem->list, &test_list);
    }

    for_each_possible_cpu(i) {
        per_cpu(kmemleak_test_pointer, i) = kmalloc(129, GFP_KERNEL);
        pr_info("kmemleak: kmalloc(129) = %p\n",
            per_cpu(kmemleak_test_pointer, i));
    }

    return 0;
}
module_init(kmemleak_test_init);

static void __exit kmemleak_test_exit(void)
{
    struct test_node *elem, *tmp;

    /*
     * Remove the list elements without actually freeing the
     * memory.
     */
    list_for_each_entry_safe(elem, tmp, &test_list, list)
        list_del(&elem->list);
}
module_exit(kmemleak_test_exit);

MODULE_LICENSE("GPL");