1/* x86 internal rwlock struct definitions.
2 Copyright (C) 2019-2022 Free Software Foundation, Inc.
3
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 <http://www.gnu.org/licenses/>. */
19
20#ifndef _RWLOCK_INTERNAL_H
21#define _RWLOCK_INTERNAL_H
22
23struct __pthread_rwlock_arch_t
24{
25 unsigned int __readers;
26 unsigned int __writers;
27 unsigned int __wrphase_futex;
28 unsigned int __writers_futex;
29 unsigned int __pad3;
30 unsigned int __pad4;
31#ifdef __x86_64__
32 int __cur_writer;
33 int __shared;
34 signed char __rwelision;
35# ifdef __ILP32__
36 unsigned char __pad1[3];
37# define __PTHREAD_RWLOCK_ELISION_EXTRA 0, { 0, 0, 0 }
38# else
39 unsigned char __pad1[7];
40# define __PTHREAD_RWLOCK_ELISION_EXTRA 0, { 0, 0, 0, 0, 0, 0, 0 }
41# endif
42 unsigned long int __pad2;
43 /* FLAGS must stay at this position in the structure to maintain
44 binary compatibility. */
45 unsigned int __flags;
46#else /* __x86_64__ */
47 /* FLAGS must stay at this position in the structure to maintain
48 binary compatibility. */
49 unsigned char __flags;
50 unsigned char __shared;
51 signed char __rwelision;
52 unsigned char __pad2;
53 int __cur_writer;
54#endif
55};
56
57#ifdef __x86_64__
58# define __PTHREAD_RWLOCK_INITIALIZER(__flags) \
59 0, 0, 0, 0, 0, 0, 0, 0, __PTHREAD_RWLOCK_ELISION_EXTRA, 0, __flags
60#else
61# define __PTHREAD_RWLOCK_INITIALIZER(__flags) \
62 0, 0, 0, 0, 0, 0, __flags, 0, 0, 0, 0
63#endif
64
65#endif
66

source code of include/x86_64-linux-gnu/bits/struct_rwlock.h