/*
 * Out Of Memory (OOM) for Memory Resource Controller
 *
 * The program is designed to cope with unpredictable like amount and
 * system physical memory, swap size and other VMM technology like KSM,
 * memcg, memory hotplug and so on which may affect the OOM
 * behaviours. It simply increase the memory consumption 3G each time
 * until all the available memory is consumed and OOM is triggered.
 *
 * Copyright (C) 2010-2017  Red Hat, Inc.
 *
 * This program is free software;  you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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.
 */

#include "config.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#if HAVE_NUMA_H
#include <numa.h>
#endif

#include "numa_helper.h"
#include "mem.h"

#ifdef HAVE_NUMA_V2

static int memcg_mounted;

static void verify_oom(void)
{
#if __WORDSIZE == 32
	tst_brk(TCONF, "test is not designed for 32-bit system.");
#endif

	SAFE_FILE_PRINTF(MEMCG_PATH_NEW "/tasks", "%d", getpid());
	SAFE_FILE_PRINTF(MEMCG_LIMIT, "%ld", TESTMEM);

	testoom(0, 0, ENOMEM, 1);

	if (access(MEMCG_SW_LIMIT, F_OK) == -1) {
		if (errno == ENOENT)
			tst_res(TCONF,
				"memcg swap accounting is disabled");
		else
			tst_brk(TBROK | TERRNO, "access");
	} else {
		SAFE_FILE_PRINTF(MEMCG_SW_LIMIT, "%ld", TESTMEM);
		testoom(0, 1, ENOMEM, 1);
	}

	/* OOM for MEMCG with mempolicy */
	if (is_numa(NULL, NH_MEMS, 2)) {
		tst_res(TINFO, "OOM on MEMCG & mempolicy...");
		testoom(MPOL_BIND, 0, ENOMEM, 1);
		testoom(MPOL_INTERLEAVE, 0, ENOMEM, 1);
		testoom(MPOL_PREFERRED, 0, ENOMEM, 1);
	}
}

static void setup(void)
{
	overcommit = get_sys_tune("overcommit_memory");
	set_sys_tune("overcommit_memory", 1, 1);
	mount_mem("memcg", "cgroup", "memory", MEMCG_PATH, MEMCG_PATH_NEW);
	memcg_mounted = 1;
}

static void cleanup(void)
{
	if (overcommit != -1)
		set_sys_tune("overcommit_memory", overcommit, 0);
	if (memcg_mounted)
		umount_mem(MEMCG_PATH, MEMCG_PATH_NEW);
}

static struct tst_test test = {
	.needs_root = 1,
	.forks_child = 1,
	.timeout = -1,
	.setup = setup,
	.cleanup = cleanup,
	.test_all = verify_oom,
};

#else
	TST_TEST_TCONF(NUMA_ERROR_MSG);
#endif