1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0+ 2*4882a593Smuzhiyun /* 3*4882a593Smuzhiyun * test_free_pages.c: Check that free_pages() doesn't leak memory 4*4882a593Smuzhiyun * Copyright (c) 2020 Oracle 5*4882a593Smuzhiyun * Author: Matthew Wilcox <willy@infradead.org> 6*4882a593Smuzhiyun */ 7*4882a593Smuzhiyun 8*4882a593Smuzhiyun #include <linux/gfp.h> 9*4882a593Smuzhiyun #include <linux/mm.h> 10*4882a593Smuzhiyun #include <linux/module.h> 11*4882a593Smuzhiyun test_free_pages(gfp_t gfp)12*4882a593Smuzhiyunstatic void test_free_pages(gfp_t gfp) 13*4882a593Smuzhiyun { 14*4882a593Smuzhiyun unsigned int i; 15*4882a593Smuzhiyun 16*4882a593Smuzhiyun for (i = 0; i < 1000 * 1000; i++) { 17*4882a593Smuzhiyun unsigned long addr = __get_free_pages(gfp, 3); 18*4882a593Smuzhiyun struct page *page = virt_to_page(addr); 19*4882a593Smuzhiyun 20*4882a593Smuzhiyun /* Simulate page cache getting a speculative reference */ 21*4882a593Smuzhiyun get_page(page); 22*4882a593Smuzhiyun free_pages(addr, 3); 23*4882a593Smuzhiyun put_page(page); 24*4882a593Smuzhiyun } 25*4882a593Smuzhiyun } 26*4882a593Smuzhiyun m_in(void)27*4882a593Smuzhiyunstatic int m_in(void) 28*4882a593Smuzhiyun { 29*4882a593Smuzhiyun test_free_pages(GFP_KERNEL); 30*4882a593Smuzhiyun test_free_pages(GFP_KERNEL | __GFP_COMP); 31*4882a593Smuzhiyun 32*4882a593Smuzhiyun return 0; 33*4882a593Smuzhiyun } 34*4882a593Smuzhiyun m_ex(void)35*4882a593Smuzhiyunstatic void m_ex(void) 36*4882a593Smuzhiyun { 37*4882a593Smuzhiyun } 38*4882a593Smuzhiyun 39*4882a593Smuzhiyun module_init(m_in); 40*4882a593Smuzhiyun module_exit(m_ex); 41*4882a593Smuzhiyun MODULE_AUTHOR("Matthew Wilcox <willy@infradead.org>"); 42*4882a593Smuzhiyun MODULE_LICENSE("GPL"); 43