1/* Returns whether Priority Inheritance support CLOCK_MONOTONIC.
2 Copyright (C) 2021-2023 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#include <support/xthread.h>
20#include <sys/syscall.h>
21#include <unistd.h>
22
23bool
24support_mutex_pi_monotonic (void)
25{
26#ifdef __linux__
27# ifndef __NR_futex
28# define __NR_futex __NR_futex_time64
29# endif
30 int r = syscall (__NR_futex, &(unsigned int){0}, 13 /* FUTEX_LOCK_PI2 */,
31 0, NULL);
32 return r == 0;
33#else
34 return false;
35#endif
36}
37