1 /* HPPA  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 
23 struct __pthread_rwlock_arch_t
24 {
25   /* In the old Linuxthreads pthread_rwlock_t, this is the
26      start of the 4-word 16-byte aligned lock structure. The
27      next four words are all set to 1 by the Linuxthreads
28      PTHREAD_RWLOCK_INITIALIZER. We ignore them in NPTL.  */
29   int __compat_padding[4] __attribute__ ((__aligned__(16)));
30   unsigned int __readers;
31   unsigned int __writers;
32   unsigned int __wrphase_futex;
33   unsigned int __writers_futex;
34   unsigned int __pad3;
35   unsigned int __pad4;
36   int __cur_writer;
37   /* An unused word, reserved for future use. It was added
38      to maintain the location of the flags from the Linuxthreads
39      layout of this structure.  */
40   int __reserved1;
41   /* FLAGS must stay at this position in the structure to maintain
42      binary compatibility.  */
43   unsigned char __pad2;
44   unsigned char __pad1;
45   unsigned char __shared;
46   unsigned char __flags;
47   /* The NPTL pthread_rwlock_t is 4 words smaller than the
48      Linuxthreads version. One word is in the middle of the
49      structure, the other three are at the end.  */
50   int __reserved2;
51   int __reserved3;
52   int __reserved4;
53 };
54 
55 #define __PTHREAD_RWLOCK_INITIALIZER(__flags) \
56   { 0, 0, 0, 0 }, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, __flags, 0, 0, 0
57 
58 #endif
59