t_filedesc.c revision 314817 
1/*	$NetBSD: t_filedesc.c,v 1.6 2017/01/13 21:30:41 christos Exp $	*/
2
3/*-
4 * Copyright (c) 2010 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#include <sys/cdefs.h>
30__RCSID("$NetBSD: t_filedesc.c,v 1.6 2017/01/13 21:30:41 christos Exp $");
31
32#include <sys/types.h>
33
34#include <assert.h>
35#include <atf-c.h>
36#include <fcntl.h>
37#include <stdlib.h>
38#include <pthread.h>
39
40#include <rump/rump.h>
41#include <rump/rump_syscalls.h>
42
43#include "h_macros.h"
44
45ATF_TC(getfilerace);
46ATF_TC_HEAD(getfilerace, tc)
47{
48
49	atf_tc_set_md_var(tc, "descr", "race between multithreaded proc. "
50	    "fd_getfile() and fd_close() (PR kern/43694)");
51}
52
53static int fd;
54static volatile bool quit;
55
56static void *
57wrkwrk(void *arg)
58{
59
60	/* just something to cause fd_getfile() to be called */
61	while (!quit)
62		rump_sys_write(fd, &fd, sizeof(fd));
63
64	return NULL;
65}
66
67/* for me, 1000 triggers extremely seldom, 10k sometimes, 100k almost always */
68#define DEFAULT_ITERATIONS 10000
69
70ATF_TC_BODY(getfilerace, tc)
71{
72	pthread_t pt;
73	int fd_wrk;
74	int i, iters;
75
76	/*
77	 * Want a multiprocessor virtual kernel.  A multiprocessor host
78	 * probably helps too, but that's harder to do in software...
79	 */
80	setenv("RUMP_NCPU", "2", 1);
81	rump_init();
82
83	fd = fd_wrk = rump_sys_open("/dev/null", O_RDWR, 0);
84	if (fd == -1)
85		atf_tc_fail_errno("cannot open /dev/null");
86
87	if (atf_tc_has_config_var(tc, "iters"))
88		iters = atoi(atf_tc_get_config_var(tc, "iters"));
89	else
90		iters = DEFAULT_ITERATIONS;
91
92	pthread_create(&pt, NULL, wrkwrk, NULL);
93	for (i = 0; i < iters; i++) {
94		rump_sys_close(fd_wrk);
95		fd_wrk = rump_sys_open("/dev/null", O_RDWR, 0);
96		assert(fd == fd_wrk);
97	}
98
99	quit = true;
100	pthread_join(pt, NULL);
101}
102
103ATF_TP_ADD_TCS(tp)
104{
105	ATF_TP_ADD_TC(tp, getfilerace);
106
107	return atf_no_error();
108}
109