1 /* Verify that pthread_[gs]etattr_default_np work correctly.
2
3 Copyright (C) 2013-2023 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
5
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
10
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <https://www.gnu.org/licenses/>. */
19
20 #include <pthread.h>
21 #include <stdio.h>
22 #include <stdint.h>
23 #include <string.h>
24 #include <unistd.h>
25 #include <errno.h>
26 #include <stdbool.h>
27
28 #define RETURN_IF_FAIL(f, ...) \
29 ({ \
30 int ret = f (__VA_ARGS__); \
31 if (ret != 0) \
32 { \
33 printf ("%s:%d: %s returned %d (errno = %d)\n", __FILE__, __LINE__, \
34 #f, ret, errno); \
35 return ret; \
36 } \
37 })
38
39 static int (*verify_result) (pthread_attr_t *);
40 static size_t stacksize = 1024 * 1024;
41 static size_t guardsize;
42 static bool do_join = true;
43 static int running = 0;
44 static int detach_failed = 0;
45 static pthread_mutex_t m = PTHREAD_MUTEX_INITIALIZER;
46 static pthread_cond_t c = PTHREAD_COND_INITIALIZER;
47
48 static void *
49 thr (void *unused __attribute__ ((unused)))
50 {
51 pthread_attr_t attr;
52 int ret;
53
54 memset (&attr, 0xab, sizeof attr);
55 /* To verify that the pthread_setattr_default_np worked. */
56 if ((ret = pthread_getattr_default_np (&attr)) != 0)
57 {
58 printf ("pthread_getattr_default_np failed: %s\n", strerror (ret));
59 goto out;
60 }
61
62 if ((ret = (*verify_result) (&attr)) != 0)
63 goto out;
64
65 memset (&attr, 0xab, sizeof attr);
66 /* To verify that the attributes actually got applied. */
67 if ((ret = pthread_getattr_np (pthread_self (), &attr)) != 0)
68 {
69 printf ("pthread_getattr_default_np failed: %s\n", strerror (ret));
70 goto out;
71 }
72
73 ret = (*verify_result) (&attr);
74
75 out:
76 if (!do_join)
77 {
78 pthread_mutex_lock (&m);
79 running--;
80 pthread_cond_signal (&c);
81 pthread_mutex_unlock (&m);
82
83 detach_failed |= ret;
84 }
85
86 return (void *) (uintptr_t) ret;
87 }
88
89 static int
90 run_threads (const pthread_attr_t *attr)
91 {
92 pthread_t t;
93 void *tret = NULL;
94
95 RETURN_IF_FAIL (pthread_setattr_default_np, attr);
96
97 /* Run twice to ensure that the attributes do not get overwritten in the
98 first run somehow. */
99 for (int i = 0; i < 2; i++)
100 {
101 RETURN_IF_FAIL (pthread_create, &t, NULL, thr, NULL);
102 if (do_join)
103 RETURN_IF_FAIL (pthread_join, t, &tret);
104 else
105 {
106 pthread_mutex_lock (&m);
107 running++;
108 pthread_mutex_unlock (&m);
109 }
110
111 if (tret != NULL)
112 {
113 puts ("Thread failed");
114 return 1;
115 }
116 }
117
118 /* Stay in sync for detached threads and get their status. */
119 while (!do_join)
120 {
121 pthread_mutex_lock (&m);
122 if (running == 0)
123 {
124 pthread_mutex_unlock (&m);
125 break;
126 }
127 pthread_cond_wait (&c, &m);
128 pthread_mutex_unlock (&m);
129 }
130
131 return 0;
132 }
133
134 static int
135 verify_detach_result (pthread_attr_t *attr)
136 {
137 int state;
138
139 RETURN_IF_FAIL (pthread_attr_getdetachstate, attr, &state);
140
141 if (state != PTHREAD_CREATE_DETACHED)
142 {
143 puts ("failed to set detach state");
144 return 1;
145 }
146
147 return 0;
148 }
149
150 static int
151 do_detach_test (void)
152 {
153 pthread_attr_t attr;
154
155 do_join = false;
156 RETURN_IF_FAIL (pthread_attr_init, &attr);
157 RETURN_IF_FAIL (pthread_attr_setdetachstate, &attr, PTHREAD_CREATE_DETACHED);
158
159 RETURN_IF_FAIL (run_threads, &attr);
160 return detach_failed;
161 }
162
163 static int
164 verify_affinity_result (pthread_attr_t *attr)
165 {
166 cpu_set_t cpuset;
167
168 RETURN_IF_FAIL (pthread_attr_getaffinity_np, attr, sizeof (cpuset), &cpuset);
169 if (!CPU_ISSET (0, &cpuset))
170 {
171 puts ("failed to set cpu affinity");
172 return 1;
173 }
174
175 return 0;
176 }
177
178 static int
179 do_affinity_test (void)
180 {
181 pthread_attr_t attr;
182
183 RETURN_IF_FAIL (pthread_attr_init, &attr);
184
185 /* Processor affinity. Like scheduling policy, this could fail if the user
186 does not have the necessary privileges. So we only spew a warning if
187 pthread_create fails with EPERM. A computer has at least one CPU. */
188 cpu_set_t cpuset;
189 CPU_ZERO (&cpuset);
190 CPU_SET (0, &cpuset);
191 RETURN_IF_FAIL (pthread_attr_setaffinity_np, &attr, sizeof (cpuset), &cpuset);
192
193 int ret = run_threads (&attr);
194
195 if (ret == EPERM)
196 {
197 printf ("Skipping CPU Affinity test: %s\n", strerror (ret));
198 return 0;
199 }
200 else if (ret != 0)
201 return ret;
202
203 return 0;
204 }
205
206 static int
207 verify_sched_result (pthread_attr_t *attr)
208 {
209 int inherited, policy;
210 struct sched_param param;
211
212 RETURN_IF_FAIL (pthread_attr_getinheritsched, attr, &inherited);
213 if (inherited != PTHREAD_EXPLICIT_SCHED)
214 {
215 puts ("failed to set EXPLICIT_SCHED (%d != %d)");
216 return 1;
217 }
218
219 RETURN_IF_FAIL (pthread_attr_getschedpolicy, attr, &policy);
220 if (policy != SCHED_RR)
221 {
222 printf ("failed to set SCHED_RR (%d != %d)\n", policy, SCHED_RR);
223 return 1;
224 }
225
226 RETURN_IF_FAIL (pthread_attr_getschedparam, attr, ¶m);
227 if (param.sched_priority != 42)
228 {
229 printf ("failed to set sched_priority (%d != %d)\n",
230 param.sched_priority, 42);
231 return 1;
232 }
233
234 return 0;
235 }
236
237 static int
238 do_sched_test (void)
239 {
240 pthread_attr_t attr;
241
242 RETURN_IF_FAIL (pthread_attr_init, &attr);
243
244 /* Scheduling policy. Note that we don't always test these since it's
245 possible that the user the tests run as don't have the appropriate
246 privileges. */
247 RETURN_IF_FAIL (pthread_attr_setinheritsched, &attr, PTHREAD_EXPLICIT_SCHED);
248 RETURN_IF_FAIL (pthread_attr_setschedpolicy, &attr, SCHED_RR);
249
250 struct sched_param param;
251 param.sched_priority = 42;
252 RETURN_IF_FAIL (pthread_attr_setschedparam, &attr, ¶m);
253
254 int ret = run_threads (&attr);
255
256 if (ret == EPERM)
257 {
258 printf ("Skipping Scheduler Attributes test: %s\n", strerror (ret));
259 return 0;
260 }
261 else if (ret != 0)
262 return ret;
263
264 return 0;
265 }
266
267 static int
268 verify_guardsize_result (pthread_attr_t *attr)
269 {
270 size_t guard;
271
272 RETURN_IF_FAIL (pthread_attr_getguardsize, attr, &guard);
273
274 if (guardsize != guard)
275 {
276 printf ("failed to set guardsize (%zu, %zu)\n", guardsize, guard);
277 return 1;
278 }
279
280 return 0;
281 }
282
283 static int
284 do_guardsize_test (void)
285 {
286 long int pagesize = sysconf (_SC_PAGESIZE);
287 pthread_attr_t attr;
288
289 if (pagesize < 0)
290 {
291 printf ("sysconf failed: %s\n", strerror (errno));
292 return 1;
293 }
294
295 RETURN_IF_FAIL (pthread_getattr_default_np, &attr);
296
297 /* Increase default guardsize by a page. */
298 RETURN_IF_FAIL (pthread_attr_getguardsize, &attr, &guardsize);
299 guardsize += pagesize;
300 RETURN_IF_FAIL (pthread_attr_setguardsize, &attr, guardsize);
301 RETURN_IF_FAIL (run_threads, &attr);
302
303 return 0;
304 }
305
306 static int
307 verify_stacksize_result (pthread_attr_t *attr)
308 {
309 size_t stack;
310
311 RETURN_IF_FAIL (pthread_attr_getstacksize, attr, &stack);
312
313 if (stacksize != stack)
314 {
315 printf ("failed to set default stacksize (%zu, %zu)\n", stacksize, stack);
316 return 1;
317 }
318
319 return 0;
320 }
321
322 static int
323 do_stacksize_test (void)
324 {
325 long int pagesize = sysconf (_SC_PAGESIZE);
326 pthread_attr_t attr;
327
328 if (pagesize < 0)
329 {
330 printf ("sysconf failed: %s\n", strerror (errno));
331 return 1;
332 }
333
334 /* Perturb the size by a page so that we're not aligned on the 64K boundary.
335 pthread_create does this perturbation on x86 to avoid causing the 64k
336 aliasing conflict. We want to prevent pthread_create from doing that
337 since it is not consistent for all architectures. */
338 stacksize += pagesize;
339
340 RETURN_IF_FAIL (pthread_attr_init, &attr);
341
342 /* Run twice to ensure that we don't give a false positive. */
343 RETURN_IF_FAIL (pthread_attr_setstacksize, &attr, stacksize);
344 RETURN_IF_FAIL (run_threads, &attr);
345 stacksize *= 2;
346 RETURN_IF_FAIL (pthread_attr_setstacksize, &attr, stacksize);
347 RETURN_IF_FAIL (run_threads, &attr);
348 return 0;
349 }
350
351 /* We test each attribute separately because sched and affinity tests may need
352 additional user privileges that may not be available during the test run.
353 Each attribute test is a set of two functions, viz. a function to set the
354 default attribute (do_foo_test) and another to verify its result
355 (verify_foo_result). Each test spawns a thread and checks (1) if the
356 attribute values were applied correctly and (2) if the change in the default
357 value reflected. */
358 static int
359 do_test (void)
360 {
361 puts ("stacksize test");
362 verify_result = verify_stacksize_result;
363 RETURN_IF_FAIL (do_stacksize_test);
364
365 puts ("guardsize test");
366 verify_result = verify_guardsize_result;
367 RETURN_IF_FAIL (do_guardsize_test);
368
369 puts ("sched test");
370 verify_result = verify_sched_result;
371 RETURN_IF_FAIL (do_sched_test);
372
373 puts ("affinity test");
374 verify_result = verify_affinity_result;
375 RETURN_IF_FAIL (do_affinity_test);
376
377 puts ("detach test");
378 verify_result = verify_detach_result;
379 RETURN_IF_FAIL (do_detach_test);
380
381 return 0;
382 }
383
384 #define TEST_FUNCTION do_test ()
385 #include "../test-skeleton.c"