aboutsummaryrefslogtreecommitdiff
path: root/lib/test_free_pages.c
blob: 074e76bd76b2b3c9ba25ee9639b2d7d35d7f193b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
// SPDX-License-Identifier: GPL-2.0+
/*
 * test_free_pages.c: Check that free_pages() doesn't leak memory
 * Copyright (c) 2020 Oracle
 * Author: Matthew Wilcox <willy@infradead.org>
 */

#include <linux/gfp.h>
#include <linux/mm.h>
#include <linux/module.h>

static void test_free_pages(gfp_t gfp)
{
	unsigned int i;

	for (i = 0; i < 1000 * 1000; i++) {
		unsigned long addr = __get_free_pages(gfp, 3);
		struct page *page = virt_to_page(addr);

		/* Simulate page cache getting a speculative reference */
		get_page(page);
		free_pages(addr, 3);
		put_page(page);
	}
}

static int m_in(void)
{
	test_free_pages(GFP_KERNEL);
	test_free_pages(GFP_KERNEL | __GFP_COMP);

	return 0;
}

static void m_ex(void)
{
}

module_init(m_in);
module_exit(m_ex);
MODULE_AUTHOR("Matthew Wilcox <willy@infradead.org>");
MODULE_LICENSE("GPL");