1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
|
#define _GNU_SOURCE
#include <pthread.h>
#include <stdio.h>
#include <error.h>
#include <assert.h>
#include <errno.h>
#define THREADS 500
#define WAITS 3
void *
dowait (void *arg)
{
pthread_barrier_t *barrier = arg;
int ret;
ret = pthread_barrier_wait (barrier);
printf ("%d ", pthread_self ());
return (void *) ret;
}
int
main (int argc, char **argv)
{
pthread_barrierattr_t attr;
pthread_barrier_t barrier;
int i, j;
error_t err;
pthread_t tid[THREADS];
int havesyncs;
err = pthread_barrierattr_init (&attr);
if (err)
error (1, err, "pthread_barrierattr_init");
err = pthread_barrierattr_getpshared (&attr, &i);
if (err)
error (1, err, "pthread_barrierattr_getpshared");
assert (i == PTHREAD_PROCESS_PRIVATE || i == PTHREAD_PROCESS_SHARED);
err = pthread_barrierattr_setpshared (&attr, PTHREAD_PROCESS_PRIVATE);
if (err)
error (1, err, "pthread_barrierattr_setpshared");
err = pthread_barrier_init (&barrier, &attr, THREADS + 1);
if (err)
error (1, err, "pthread_barrier_init");
for (j = 0; j < WAITS; j ++)
{
for (i = 0; i < THREADS; i ++)
{
err = pthread_create (&tid[i], 0, dowait, &barrier);
if (err)
error (1, err, "pthread_create (%d)", i);
}
printf ("Manager will now call pthread_barrier_wait.\n");
havesyncs
= pthread_barrier_wait (&barrier) == PTHREAD_BARRIER_SERIAL_THREAD
? 1 : 0;
for (i = THREADS - 1; i >= 0; i --)
{
void *ret;
err = pthread_join (tid[i], &ret);
if (err)
error (1, err, "pthread_join");
switch ((int) ret)
{
case 0:
break;
case PTHREAD_BARRIER_SERIAL_THREAD:
havesyncs ++;
break;
default:
assert (! "Unknown value returned from pthread_barrier_wait.");
break;
}
}
printf ("\n");
assert (havesyncs == 1);
}
return 0;
}
|
