1 | /* Copyright (C) 2002-2024 Free Software Foundation, Inc. |
2 | This file is part of the GNU C Library. |
3 | |
4 | The GNU C Library is free software; you can redistribute it and/or |
5 | modify it under the terms of the GNU Lesser General Public |
6 | License as published by the Free Software Foundation; either |
7 | version 2.1 of the License, or (at your option) any later version. |
8 | |
9 | The GNU C Library is distributed in the hope that it will be useful, |
10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
12 | Lesser General Public License for more details. |
13 | |
14 | You should have received a copy of the GNU Lesser General Public |
15 | License along with the GNU C Library; if not, see |
16 | <https://www.gnu.org/licenses/>. */ |
17 | |
18 | #include <errno.h> |
19 | #include <pthread.h> |
20 | #include <stdint.h> |
21 | #include <stdio.h> |
22 | #include <stdlib.h> |
23 | #include <string.h> |
24 | #include <unistd.h> |
25 | #include <sys/mman.h> |
26 | #include <sys/wait.h> |
27 | |
28 | |
29 | static int |
30 | do_test (void) |
31 | { |
32 | size_t ps = sysconf (_SC_PAGESIZE); |
33 | char tmpfname[] = "/tmp/tst-spin2.XXXXXX" ; |
34 | char data[ps]; |
35 | void *mem; |
36 | int fd; |
37 | pthread_spinlock_t *s; |
38 | pid_t pid; |
39 | char *p; |
40 | int err; |
41 | |
42 | fd = mkstemp (template: tmpfname); |
43 | if (fd == -1) |
44 | { |
45 | printf (format: "cannot open temporary file: %m\n" ); |
46 | return 1; |
47 | } |
48 | |
49 | /* Make sure it is always removed. */ |
50 | unlink (name: tmpfname); |
51 | |
52 | /* Create one page of data. */ |
53 | memset (data, '\0', ps); |
54 | |
55 | /* Write the data to the file. */ |
56 | if (write (fd, data, ps) != (ssize_t) ps) |
57 | { |
58 | puts (s: "short write" ); |
59 | return 1; |
60 | } |
61 | |
62 | mem = mmap (NULL, len: ps, PROT_READ | PROT_WRITE, MAP_SHARED, fd: fd, offset: 0); |
63 | if (mem == MAP_FAILED) |
64 | { |
65 | printf (format: "mmap failed: %m\n" ); |
66 | return 1; |
67 | } |
68 | |
69 | s = (pthread_spinlock_t *) (((uintptr_t) mem |
70 | + __alignof (pthread_spinlock_t)) |
71 | & ~(__alignof (pthread_spinlock_t) - 1)); |
72 | p = (char *) (s + 1); |
73 | |
74 | if (pthread_spin_init (lock: s, PTHREAD_PROCESS_SHARED) != 0) |
75 | { |
76 | puts (s: "spin_init failed" ); |
77 | return 1; |
78 | } |
79 | |
80 | if (pthread_spin_lock (lock: s) != 0) |
81 | { |
82 | puts (s: "spin_lock failed" ); |
83 | return 1; |
84 | } |
85 | |
86 | err = pthread_spin_trylock (lock: s); |
87 | if (err == 0) |
88 | { |
89 | puts (s: "1st spin_trylock succeeded" ); |
90 | return 1; |
91 | } |
92 | else if (err != EBUSY) |
93 | { |
94 | puts (s: "1st spin_trylock didn't return EBUSY" ); |
95 | return 1; |
96 | } |
97 | |
98 | err = pthread_spin_unlock (lock: s); |
99 | if (err != 0) |
100 | { |
101 | puts (s: "parent: spin_unlock failed" ); |
102 | return 1; |
103 | } |
104 | |
105 | err = pthread_spin_trylock (lock: s); |
106 | if (err != 0) |
107 | { |
108 | puts (s: "2nd spin_trylock failed" ); |
109 | return 1; |
110 | } |
111 | |
112 | *p = 0; |
113 | |
114 | puts (s: "going to fork now" ); |
115 | pid = fork (); |
116 | if (pid == -1) |
117 | { |
118 | puts (s: "fork failed" ); |
119 | return 1; |
120 | } |
121 | else if (pid == 0) |
122 | { |
123 | /* Play some lock ping-pong. It's our turn to unlock first. */ |
124 | if ((*p)++ != 0) |
125 | { |
126 | puts (s: "child: *p != 0" ); |
127 | return 1; |
128 | } |
129 | |
130 | if (pthread_spin_unlock (lock: s) != 0) |
131 | { |
132 | puts (s: "child: 1st spin_unlock failed" ); |
133 | return 1; |
134 | } |
135 | |
136 | puts (s: "child done" ); |
137 | } |
138 | else |
139 | { |
140 | if (pthread_spin_lock (lock: s) != 0) |
141 | { |
142 | puts (s: "parent: 2nd spin_lock failed" ); |
143 | return 1; |
144 | } |
145 | |
146 | puts (s: "waiting for child" ); |
147 | |
148 | waitpid (pid: pid, NULL, options: 0); |
149 | |
150 | puts (s: "parent done" ); |
151 | } |
152 | |
153 | return 0; |
154 | } |
155 | |
156 | #define TEST_FUNCTION do_test () |
157 | #include "../test-skeleton.c" |
158 | |