1 /* $NetBSD: t_scan.c,v 1.2 2021/10/10 19:17:31 wiz Exp $ */
2
3 /*-
4 * Copyright (c) 2021 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_scan.c,v 1.2 2021/10/10 19:17:31 wiz Exp $");
31
32 #include <sys/event.h>
33 #include <sys/time.h>
34 #include <sys/types.h>
35
36 #include <err.h>
37 #include <pthread.h>
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <unistd.h>
41
42 #include <atf-c.h>
43
44 /*
45 * Each kevent thread will make this many kevent() calls, and if it
46 * achieves this mark, we assume the race condition has not occurred
47 * the declare the test passes.
48 */
49 #define NKEVENT_CALLS 10000
50
51 static int kq;
52
53 static void *
kevent_thread(void * arg)54 kevent_thread(void *arg)
55 {
56 struct timespec ts = { 0, 0 };
57 struct kevent event;
58 int rv, i;
59
60 for (i = 0; i < NKEVENT_CALLS; i++) {
61 rv = kevent(kq, NULL, 0, &event, 1, &ts);
62 if (rv < 0) {
63 i = rv;
64 break;
65 }
66 if (rv != 1) {
67 break;
68 }
69 }
70
71 return (void *)(intptr_t)i;
72 }
73
74 ATF_TC(scan1);
ATF_TC_HEAD(scan1,tc)75 ATF_TC_HEAD(scan1, tc)
76 {
77 atf_tc_set_md_var(tc, "descr",
78 "Exercises multi-threaded kevent() calls (PR kern/50094)");
79 }
80
ATF_TC_BODY(scan1,tc)81 ATF_TC_BODY(scan1, tc)
82 {
83 pthread_t t1, t2;
84 void *v1, *v2;
85 intptr_t r1, r2;
86 struct kevent event;
87 int p[2];
88
89 ATF_REQUIRE(pipe(p) == 0);
90 ATF_REQUIRE((kq = kqueue()) >= 0);
91
92 EV_SET(&event, p[0], EVFILT_READ, EV_ADD, 0, 0, 0);
93 ATF_REQUIRE(kevent(kq, &event, 1, NULL, 0, NULL) == 0);
94 ATF_REQUIRE(write(p[1], p, 1) == 1);
95
96 ATF_REQUIRE(pthread_create(&t1, NULL, kevent_thread, NULL) == 0);
97 ATF_REQUIRE(pthread_create(&t2, NULL, kevent_thread, NULL) == 0);
98
99 ATF_REQUIRE(pthread_join(t1, &v1) == 0);
100 r1 = (intptr_t)v1;
101
102 ATF_REQUIRE(pthread_join(t2, &v2) == 0);
103 r2 = (intptr_t)v2;
104
105 ATF_REQUIRE(r1 >= 0);
106 ATF_REQUIRE(r2 >= 0);
107
108 ATF_REQUIRE(r1 == NKEVENT_CALLS);
109 ATF_REQUIRE(r2 == NKEVENT_CALLS);
110 }
111
ATF_TP_ADD_TCS(tp)112 ATF_TP_ADD_TCS(tp)
113 {
114 ATF_TP_ADD_TC(tp, scan1);
115
116 return atf_no_error();
117 }
118