1/******************************************************************************
2 *
3 * Copyright FUJITSU LIMITED 2010
4 * Copyright KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
5 *
6 *   This program is free software;  you can redistribute it and/or modify
7 *   it under the terms of the GNU General Public License as published by
8 *   the Free Software Foundation; either version 2 of the License, or
9 *   (at your option) any later version.
10 *
11 * DESCRIPTION
12 *      Wait on uninitialized heap. It shold be zero and FUTEX_WAIT should
13 *      return immediately. This test is intent to test zero page handling in
14 *      futex.
15 *
16 * AUTHOR
17 *      KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
18 *
19 * HISTORY
20 *      2010-Jan-6: Initial version by KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
21 *
22 *****************************************************************************/
23
24#include <pthread.h>
25#include <stdio.h>
26#include <stdlib.h>
27#include <sys/mman.h>
28#include <syscall.h>
29#include <sys/types.h>
30#include <sys/stat.h>
31#include <unistd.h>
32#include <errno.h>
33#include <linux/futex.h>
34#include <libgen.h>
35
36#include "logging.h"
37#include "futextest.h"
38
39#define TEST_NAME "futex-wait-uninitialized-heap"
40#define WAIT_US 5000000
41
42static int child_blocked = 1;
43static int child_ret;
44void *buf;
45
46void usage(char *prog)
47{
48	printf("Usage: %s\n", prog);
49	printf("  -c	Use color\n");
50	printf("  -h	Display this help message\n");
51	printf("  -v L	Verbosity level: %d=QUIET %d=CRITICAL %d=INFO\n",
52	       VQUIET, VCRITICAL, VINFO);
53}
54
55void *wait_thread(void *arg)
56{
57	int res;
58
59	child_ret = RET_PASS;
60	res = futex_wait(buf, 1, NULL, 0);
61	child_blocked = 0;
62
63	if (res != 0 && errno != EWOULDBLOCK) {
64		error("futex failure\n", errno);
65		child_ret = RET_ERROR;
66	}
67	pthread_exit(NULL);
68}
69
70int main(int argc, char **argv)
71{
72	int c, ret = RET_PASS;
73	long page_size;
74	pthread_t thr;
75
76	while ((c = getopt(argc, argv, "chv:")) != -1) {
77		switch (c) {
78		case 'c':
79			log_color(1);
80			break;
81		case 'h':
82			usage(basename(argv[0]));
83			exit(0);
84		case 'v':
85			log_verbosity(atoi(optarg));
86			break;
87		default:
88			usage(basename(argv[0]));
89			exit(1);
90		}
91	}
92
93	page_size = sysconf(_SC_PAGESIZE);
94
95	buf = mmap(NULL, page_size, PROT_READ|PROT_WRITE,
96		   MAP_PRIVATE|MAP_ANONYMOUS, 0, 0);
97	if (buf == (void *)-1) {
98		error("mmap\n", errno);
99		exit(1);
100	}
101
102	ksft_print_header();
103	ksft_print_msg("%s: Test the uninitialized futex value in FUTEX_WAIT\n",
104	       basename(argv[0]));
105
106
107	ret = pthread_create(&thr, NULL, wait_thread, NULL);
108	if (ret) {
109		error("pthread_create\n", errno);
110		ret = RET_ERROR;
111		goto out;
112	}
113
114	info("waiting %dus for child to return\n", WAIT_US);
115	usleep(WAIT_US);
116
117	ret = child_ret;
118	if (child_blocked) {
119		fail("child blocked in kernel\n");
120		ret = RET_FAIL;
121	}
122
123 out:
124	print_result(TEST_NAME, ret);
125	return ret;
126}
127