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
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
|
/* Test for sched_getaffinity and sched_setaffinity, PID version.
Copyright (C) 2015-2021 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
/* Function definitions for the benefit of tst-skeleton-affinity.c.
This variant forks a child process which then invokes
sched_getaffinity and sched_setaffinity on the parent PID. */
#include <errno.h>
#include <stdlib.h>
#include <sched.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/wait.h>
#include <unistd.h>
static int
write_fully (int fd, const void *buffer, size_t length)
{
const void *end = buffer + length;
while (buffer < end)
{
ssize_t bytes_written = TEMP_FAILURE_RETRY
(write (fd, buffer, end - buffer));
if (bytes_written < 0)
return -1;
if (bytes_written == 0)
{
errno = ENOSPC;
return -1;
}
buffer += bytes_written;
}
return 0;
}
static ssize_t
read_fully (int fd, void *buffer, size_t length)
{
const void *start = buffer;
const void *end = buffer + length;
while (buffer < end)
{
ssize_t bytes_read = TEMP_FAILURE_RETRY
(read (fd, buffer, end - buffer));
if (bytes_read < 0)
return -1;
if (bytes_read == 0)
return buffer - start;
buffer += bytes_read;
}
return length;
}
static int
process_child_response (int *pipes, pid_t child,
cpu_set_t *set, size_t size)
{
close (pipes[1]);
int value_from_child;
ssize_t bytes_read = read_fully
(pipes[0], &value_from_child, sizeof (value_from_child));
if (bytes_read < 0)
{
printf ("error: read from child: %m\n");
exit (1);
}
if (bytes_read != sizeof (value_from_child))
{
printf ("error: not enough bytes from child: %zd\n", bytes_read);
exit (1);
}
if (value_from_child == 0)
{
bytes_read = read_fully (pipes[0], set, size);
if (bytes_read < 0)
{
printf ("error: read: %m\n");
exit (1);
}
if (bytes_read != size)
{
printf ("error: not enough bytes from child: %zd\n", bytes_read);
exit (1);
}
}
int status;
if (waitpid (child, &status, 0) < 0)
{
printf ("error: waitpid: %m\n");
exit (1);
}
if (!(WIFEXITED (status) && WEXITSTATUS (status) == 0))
{
printf ("error: invalid status from : %m\n");
exit (1);
}
close (pipes[0]);
if (value_from_child != 0)
{
errno = value_from_child;
return -1;
}
return 0;
}
static int
getaffinity (size_t size, cpu_set_t *set)
{
int pipes[2];
if (pipe (pipes) < 0)
{
printf ("error: pipe: %m\n");
exit (1);
}
int ret = fork ();
if (ret < 0)
{
printf ("error: fork: %m\n");
exit (1);
}
if (ret == 0)
{
/* Child. */
int ret = sched_getaffinity (getppid (), size, set);
if (ret < 0)
ret = errno;
if (write_fully (pipes[1], &ret, sizeof (ret)) < 0
|| write_fully (pipes[1], set, size) < 0
|| (ret == 0 && write_fully (pipes[1], set, size) < 0))
{
printf ("error: write: %m\n");
_exit (1);
}
_exit (0);
}
/* Parent. */
return process_child_response (pipes, ret, set, size);
}
static int
setaffinity (size_t size, const cpu_set_t *set)
{
int pipes[2];
if (pipe (pipes) < 0)
{
printf ("error: pipe: %m\n");
exit (1);
}
int ret = fork ();
if (ret < 0)
{
printf ("error: fork: %m\n");
exit (1);
}
if (ret == 0)
{
/* Child. */
int ret = sched_setaffinity (getppid (), size, set);
if (write_fully (pipes[1], &ret, sizeof (ret)) < 0)
{
printf ("error: write: %m\n");
_exit (1);
}
_exit (0);
}
/* Parent. There is no affinity mask to read from the child, so the
size is 0. */
return process_child_response (pipes, ret, NULL, 0);
}
struct conf;
static bool early_test (struct conf *unused)
{
return true;
}
#include "tst-skeleton-affinity.c"
|
