1 /* Copyright (C) 2002-2022 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18 #include <errno.h>
19 #include <sched.h>
20 #include <string.h>
21 #include "pthreadP.h"
22 #include <lowlevellock.h>
23
24
25 int
__pthread_setschedparam(pthread_t threadid,int policy,const struct sched_param * param)26 __pthread_setschedparam (pthread_t threadid, int policy,
27 const struct sched_param *param)
28 {
29 struct pthread *pd = (struct pthread *) threadid;
30
31 /* Make sure the descriptor is valid. */
32 if (INVALID_TD_P (pd))
33 /* Not a valid thread handle. */
34 return ESRCH;
35
36 int result = 0;
37
38 /* See CREATE THREAD NOTES in nptl/pthread_create.c. */
39 lll_lock (pd->lock, LLL_PRIVATE);
40
41 struct sched_param p;
42 const struct sched_param *orig_param = param;
43
44 /* If the thread should have higher priority because of some
45 PTHREAD_PRIO_PROTECT mutexes it holds, adjust the priority. */
46 if (__builtin_expect (pd->tpp != NULL, 0)
47 && pd->tpp->priomax > param->sched_priority)
48 {
49 p = *param;
50 p.sched_priority = pd->tpp->priomax;
51 param = &p;
52 }
53
54 /* Try to set the scheduler information. */
55 if (__builtin_expect (__sched_setscheduler (pd->tid, policy,
56 param) == -1, 0))
57 result = errno;
58 else
59 {
60 /* We succeeded changing the kernel information. Reflect this
61 change in the thread descriptor. */
62 pd->schedpolicy = policy;
63 memcpy (&pd->schedparam, orig_param, sizeof (struct sched_param));
64 pd->flags |= ATTR_FLAG_SCHED_SET | ATTR_FLAG_POLICY_SET;
65 }
66
67 lll_unlock (pd->lock, LLL_PRIVATE);
68
69 return result;
70 }
71 strong_alias (__pthread_setschedparam, pthread_setschedparam)
72