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 <string.h>
20#include "pthreadP.h"
21#include <lowlevellock.h>
22
23
24int
25__pthread_getschedparam (pthread_t threadid, int *policy,
26 struct sched_param *param)
27{
28 struct pthread *pd = (struct pthread *) threadid;
29
30 /* Make sure the descriptor is valid. */
31 if (INVALID_TD_P (pd))
32 /* Not a valid thread handle. */
33 return ESRCH;
34
35 int result = 0;
36
37 /* See CREATE THREAD NOTES in nptl/pthread_create.c. */
38 lll_lock (pd->lock, LLL_PRIVATE);
39
40 /* The library is responsible for maintaining the values at all
41 times. If the user uses an interface other than
42 pthread_setschedparam to modify the scheduler setting it is not
43 the library's problem. In case the descriptor's values have
44 not yet been retrieved do it now. */
45 if ((pd->flags & ATTR_FLAG_SCHED_SET) == 0)
46 {
47 if (__sched_getparam (pd->tid, &pd->schedparam) != 0)
48 result = 1;
49 else
50 pd->flags |= ATTR_FLAG_SCHED_SET;
51 }
52
53 if ((pd->flags & ATTR_FLAG_POLICY_SET) == 0)
54 {
55 pd->schedpolicy = __sched_getscheduler (pd->tid);
56 if (pd->schedpolicy == -1)
57 result = 1;
58 else
59 pd->flags |= ATTR_FLAG_POLICY_SET;
60 }
61
62 if (result == 0)
63 {
64 *policy = pd->schedpolicy;
65 memcpy (param, &pd->schedparam, sizeof (struct sched_param));
66 }
67
68 lll_unlock (pd->lock, LLL_PRIVATE);
69
70 return result;
71}
72libc_hidden_def (__pthread_getschedparam)
73strong_alias (__pthread_getschedparam, pthread_getschedparam)
74

source code of glibc/nptl/pthread_getschedparam.c