1 | /* Test of POSIX barriers. |
2 | Copyright (C) 2002-2024 Free Software Foundation, Inc. |
3 | This file is part of the GNU C Library. |
4 | |
5 | The GNU C Library is free software; you can redistribute it and/or |
6 | modify it under the terms of the GNU Lesser General Public |
7 | License as published by the Free Software Foundation; either |
8 | version 2.1 of the License, or (at your option) any later version. |
9 | |
10 | The GNU C Library is distributed in the hope that it will be useful, |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
13 | Lesser General Public License for more details. |
14 | |
15 | You should have received a copy of the GNU Lesser General Public |
16 | License along with the GNU C Library; if not, see |
17 | <https://www.gnu.org/licenses/>. */ |
18 | |
19 | #include <pthread.h> |
20 | #include <stdio.h> |
21 | #include <stdlib.h> |
22 | #include <string.h> |
23 | |
24 | #define NTHREADS 20 |
25 | |
26 | #define ROUNDS 20 |
27 | |
28 | static pthread_barrier_t barriers[NTHREADS]; |
29 | |
30 | static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER; |
31 | static int counters[NTHREADS]; |
32 | static int serial[NTHREADS]; |
33 | |
34 | static void * |
35 | worker (void *arg) |
36 | { |
37 | void *result = NULL; |
38 | int nr = (long int) arg; |
39 | int i; |
40 | |
41 | for (i = 0; i < ROUNDS; ++i) |
42 | { |
43 | int j; |
44 | int retval; |
45 | |
46 | if (nr == 0) |
47 | { |
48 | memset (counters, '\0', sizeof (counters)); |
49 | memset (serial, '\0', sizeof (serial)); |
50 | } |
51 | |
52 | retval = pthread_barrier_wait (barrier: &barriers[NTHREADS - 1]); |
53 | if (retval != 0 && retval != PTHREAD_BARRIER_SERIAL_THREAD) |
54 | { |
55 | printf (format: "thread %d failed to wait for all the others\n" , nr); |
56 | result = (void *) 1; |
57 | } |
58 | |
59 | for (j = nr; j < NTHREADS; ++j) |
60 | { |
61 | /* Increment the counter for this round. */ |
62 | pthread_mutex_lock (mutex: &lock); |
63 | ++counters[j]; |
64 | pthread_mutex_unlock (mutex: &lock); |
65 | |
66 | /* Wait for the rest. */ |
67 | retval = pthread_barrier_wait (barrier: &barriers[j]); |
68 | |
69 | /* Test the result. */ |
70 | if (nr == 0 && counters[j] != j + 1) |
71 | { |
72 | printf (format: "barrier in round %d released but count is %d\n" , |
73 | j, counters[j]); |
74 | result = (void *) 1; |
75 | } |
76 | |
77 | if (retval != 0) |
78 | { |
79 | if (retval != PTHREAD_BARRIER_SERIAL_THREAD) |
80 | { |
81 | printf (format: "thread %d in round %d has nonzero return value != PTHREAD_BARRIER_SERIAL_THREAD\n" , |
82 | nr, j); |
83 | result = (void *) 1; |
84 | } |
85 | else |
86 | { |
87 | pthread_mutex_lock (mutex: &lock); |
88 | ++serial[j]; |
89 | pthread_mutex_unlock (mutex: &lock); |
90 | } |
91 | } |
92 | |
93 | /* Wait for the rest again. */ |
94 | retval = pthread_barrier_wait (barrier: &barriers[j]); |
95 | |
96 | /* Now we can check whether exactly one thread was serializing. */ |
97 | if (nr == 0 && serial[j] != 1) |
98 | { |
99 | printf (format: "not exactly one serial thread in round %d\n" , j); |
100 | result = (void *) 1; |
101 | } |
102 | } |
103 | } |
104 | |
105 | return result; |
106 | } |
107 | |
108 | |
109 | #define TEST_FUNCTION do_test () |
110 | #define TIMEOUT 60 |
111 | static int |
112 | do_test (void) |
113 | { |
114 | pthread_t threads[NTHREADS]; |
115 | int i; |
116 | void *res; |
117 | int result = 0; |
118 | |
119 | /* Initialized the barrier variables. */ |
120 | for (i = 0; i < NTHREADS; ++i) |
121 | if (pthread_barrier_init (barrier: &barriers[i], NULL, count: i + 1) != 0) |
122 | { |
123 | printf (format: "Failed to initialize barrier %d\n" , i); |
124 | exit (1); |
125 | } |
126 | |
127 | /* Start the threads. */ |
128 | for (i = 0; i < NTHREADS; ++i) |
129 | if (pthread_create (newthread: &threads[i], NULL, start_routine: worker, arg: (void *) (long int) i) != 0) |
130 | { |
131 | printf (format: "Failed to start thread %d\n" , i); |
132 | exit (1); |
133 | } |
134 | |
135 | /* And wait for them. */ |
136 | for (i = 0; i < NTHREADS; ++i) |
137 | if (pthread_join (th: threads[i], thread_return: &res) != 0 || res != NULL) |
138 | { |
139 | printf (format: "thread %d returned a failure\n" , i); |
140 | result = 1; |
141 | } |
142 | else |
143 | printf (format: "joined threads %d\n" , i); |
144 | |
145 | if (result == 0) |
146 | puts (s: "all OK" ); |
147 | |
148 | return result; |
149 | } |
150 | |
151 | #include "../test-skeleton.c" |
152 | |