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      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 
     45 ATF_TC(getfilerace);
     46 ATF_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 
     53 static int fd;
     54 static volatile bool quit;
     55 
     56 static void *
     57 wrkwrk(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 
     70 ATF_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 
    103 ATF_TP_ADD_TCS(tp)
    104 {
    105 	ATF_TP_ADD_TC(tp, getfilerace);
    106 
    107 	return atf_no_error();
    108 }
    109