1 | /* Test for sched_getaffinity and sched_setaffinity, PID version. |
2 | Copyright (C) 2015-2022 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 | /* Function definitions for the benefit of tst-skeleton-affinity.c. |
20 | This variant forks a child process which then invokes |
21 | sched_getaffinity and sched_setaffinity on the parent PID. */ |
22 | |
23 | #include <errno.h> |
24 | #include <stdlib.h> |
25 | #include <sched.h> |
26 | #include <stdbool.h> |
27 | #include <stdio.h> |
28 | #include <stdlib.h> |
29 | #include <sys/wait.h> |
30 | #include <unistd.h> |
31 | |
32 | static int |
33 | write_fully (int fd, const void *buffer, size_t length) |
34 | { |
35 | const void *end = buffer + length; |
36 | while (buffer < end) |
37 | { |
38 | ssize_t bytes_written = TEMP_FAILURE_RETRY |
39 | (write (fd, buffer, end - buffer)); |
40 | if (bytes_written < 0) |
41 | return -1; |
42 | if (bytes_written == 0) |
43 | { |
44 | errno = ENOSPC; |
45 | return -1; |
46 | } |
47 | buffer += bytes_written; |
48 | } |
49 | return 0; |
50 | } |
51 | |
52 | static ssize_t |
53 | read_fully (int fd, void *buffer, size_t length) |
54 | { |
55 | const void *start = buffer; |
56 | const void *end = buffer + length; |
57 | while (buffer < end) |
58 | { |
59 | ssize_t bytes_read = TEMP_FAILURE_RETRY |
60 | (read (fd, buffer, end - buffer)); |
61 | if (bytes_read < 0) |
62 | return -1; |
63 | if (bytes_read == 0) |
64 | return buffer - start; |
65 | buffer += bytes_read; |
66 | } |
67 | return length; |
68 | } |
69 | |
70 | static int |
71 | process_child_response (int *pipes, pid_t child, |
72 | cpu_set_t *set, size_t size) |
73 | { |
74 | close (fd: pipes[1]); |
75 | |
76 | int value_from_child; |
77 | ssize_t bytes_read = read_fully |
78 | (fd: pipes[0], buffer: &value_from_child, length: sizeof (value_from_child)); |
79 | if (bytes_read < 0) |
80 | { |
81 | printf (format: "error: read from child: %m\n" ); |
82 | exit (1); |
83 | } |
84 | if (bytes_read != sizeof (value_from_child)) |
85 | { |
86 | printf (format: "error: not enough bytes from child: %zd\n" , bytes_read); |
87 | exit (1); |
88 | } |
89 | if (value_from_child == 0) |
90 | { |
91 | bytes_read = read_fully (fd: pipes[0], buffer: set, length: size); |
92 | if (bytes_read < 0) |
93 | { |
94 | printf (format: "error: read: %m\n" ); |
95 | exit (1); |
96 | } |
97 | if (bytes_read != size) |
98 | { |
99 | printf (format: "error: not enough bytes from child: %zd\n" , bytes_read); |
100 | exit (1); |
101 | } |
102 | } |
103 | |
104 | int status; |
105 | if (waitpid (pid: child, stat_loc: &status, options: 0) < 0) |
106 | { |
107 | printf (format: "error: waitpid: %m\n" ); |
108 | exit (1); |
109 | } |
110 | if (!(WIFEXITED (status) && WEXITSTATUS (status) == 0)) |
111 | { |
112 | printf (format: "error: invalid status from : %m\n" ); |
113 | exit (1); |
114 | } |
115 | |
116 | close (fd: pipes[0]); |
117 | |
118 | if (value_from_child != 0) |
119 | { |
120 | errno = value_from_child; |
121 | return -1; |
122 | } |
123 | return 0; |
124 | } |
125 | |
126 | static int |
127 | getaffinity (size_t size, cpu_set_t *set) |
128 | { |
129 | int pipes[2]; |
130 | if (pipe (pipedes: pipes) < 0) |
131 | { |
132 | printf (format: "error: pipe: %m\n" ); |
133 | exit (1); |
134 | } |
135 | |
136 | int ret = fork (); |
137 | if (ret < 0) |
138 | { |
139 | printf (format: "error: fork: %m\n" ); |
140 | exit (1); |
141 | } |
142 | if (ret == 0) |
143 | { |
144 | /* Child. */ |
145 | int ret = sched_getaffinity (pid: getppid (), cpusetsize: size, cpuset: set); |
146 | if (ret < 0) |
147 | ret = errno; |
148 | if (write_fully (fd: pipes[1], buffer: &ret, length: sizeof (ret)) < 0 |
149 | || write_fully (fd: pipes[1], buffer: set, length: size) < 0 |
150 | || (ret == 0 && write_fully (fd: pipes[1], buffer: set, length: size) < 0)) |
151 | { |
152 | printf (format: "error: write: %m\n" ); |
153 | _exit (1); |
154 | } |
155 | _exit (0); |
156 | } |
157 | |
158 | /* Parent. */ |
159 | return process_child_response (pipes, child: ret, set, size); |
160 | } |
161 | |
162 | static int |
163 | setaffinity (size_t size, const cpu_set_t *set) |
164 | { |
165 | int pipes[2]; |
166 | if (pipe (pipedes: pipes) < 0) |
167 | { |
168 | printf (format: "error: pipe: %m\n" ); |
169 | exit (1); |
170 | } |
171 | |
172 | int ret = fork (); |
173 | if (ret < 0) |
174 | { |
175 | printf (format: "error: fork: %m\n" ); |
176 | exit (1); |
177 | } |
178 | if (ret == 0) |
179 | { |
180 | /* Child. */ |
181 | int ret = sched_setaffinity (pid: getppid (), cpusetsize: size, cpuset: set); |
182 | if (write_fully (fd: pipes[1], buffer: &ret, length: sizeof (ret)) < 0) |
183 | { |
184 | printf (format: "error: write: %m\n" ); |
185 | _exit (1); |
186 | } |
187 | _exit (0); |
188 | } |
189 | |
190 | /* Parent. There is no affinity mask to read from the child, so the |
191 | size is 0. */ |
192 | return process_child_response (pipes, child: ret, NULL, size: 0); |
193 | } |
194 | |
195 | struct conf; |
196 | static bool early_test (struct conf *unused) |
197 | { |
198 | return true; |
199 | } |
200 | |
201 | #include "tst-skeleton-affinity.c" |
202 | |