1/* Common threading primitives definitions for both POSIX and C11.
2 Copyright (C) 2017 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 <http://www.gnu.org/licenses/>. */
18
19#ifndef _THREAD_SHARED_TYPES_H
20#define _THREAD_SHARED_TYPES_H 1
21
22/* Arch-specific definitions. Each architecture must define the following
23 macros to define the expected sizes of pthread data types:
24
25 __SIZEOF_PTHREAD_ATTR_T - size of pthread_attr_t.
26 __SIZEOF_PTHREAD_MUTEX_T - size of pthread_mutex_t.
27 __SIZEOF_PTHREAD_MUTEXATTR_T - size of pthread_mutexattr_t.
28 __SIZEOF_PTHREAD_COND_T - size of pthread_cond_t.
29 __SIZEOF_PTHREAD_CONDATTR_T - size of pthread_condattr_t.
30 __SIZEOF_PTHREAD_RWLOCK_T - size of pthread_rwlock_t.
31 __SIZEOF_PTHREAD_RWLOCKATTR_T - size of pthread_rwlockattr_t.
32 __SIZEOF_PTHREAD_BARRIER_T - size of pthread_barrier_t.
33 __SIZEOF_PTHREAD_BARRIERATTR_T - size of pthread_barrierattr_t.
34
35 Also, the following macros must be define for internal pthread_mutex_t
36 struct definitions (struct __pthread_mutex_s):
37
38 __PTHREAD_COMPAT_PADDING_MID - any additional members after 'kind'
39 and before '__spin' (for 64 bits) or
40 '__nusers' (for 32 bits).
41 __PTHREAD_COMPAT_PADDING_END - any additional members at the end of
42 the internal structure.
43 __PTHREAD_MUTEX_LOCK_ELISION - 1 if the architecture supports lock
44 elision or 0 otherwise.
45 __PTHREAD_MUTEX_NUSERS_AFTER_KIND - control where to put __nusers. The
46 preferred value for new architectures
47 is 0.
48 __PTHREAD_MUTEX_USE_UNION - control whether internal __spins and
49 __list will be place inside a union for
50 linuxthreads compatibility.
51 The preferred value for new architectures
52 is 0.
53
54 For a new port the preferred values for the required defines are:
55
56 #define __PTHREAD_COMPAT_PADDING_MID
57 #define __PTHREAD_COMPAT_PADDING_END
58 #define __PTHREAD_MUTEX_LOCK_ELISION 0
59 #define __PTHREAD_MUTEX_NUSERS_AFTER_KIND 0
60 #define __PTHREAD_MUTEX_USE_UNION 0
61
62 __PTHREAD_MUTEX_LOCK_ELISION can be set to 1 if the hardware plans to
63 eventually support lock elision using transactional memory.
64
65 The additional macro defines any constraint for the lock alignment
66 inside the thread structures:
67
68 __LOCK_ALIGNMENT - for internal lock/futex usage.
69
70 Same idea but for the once locking primitive:
71
72 __ONCE_ALIGNMENT - for pthread_once_t/once_flag definition.
73
74 And finally the internal pthread_rwlock_t (struct __pthread_rwlock_arch_t)
75 must be defined.
76 */
77#include <bits/pthreadtypes-arch.h>
78
79/* Common definition of pthread_mutex_t. */
80
81#if !__PTHREAD_MUTEX_USE_UNION
82typedef struct __pthread_internal_list
83{
84 struct __pthread_internal_list *__prev;
85 struct __pthread_internal_list *__next;
86} __pthread_list_t;
87#else
88typedef struct __pthread_internal_slist
89{
90 struct __pthread_internal_slist *__next;
91} __pthread_slist_t;
92#endif
93
94/* Lock elision support. */
95#if __PTHREAD_MUTEX_LOCK_ELISION
96# if !__PTHREAD_MUTEX_USE_UNION
97# define __PTHREAD_SPINS_DATA \
98 short __spins; \
99 short __elision
100# define __PTHREAD_SPINS 0, 0
101# else
102# define __PTHREAD_SPINS_DATA \
103 struct \
104 { \
105 short __espins; \
106 short __eelision; \
107 } __elision_data
108# define __PTHREAD_SPINS { 0, 0 }
109# define __spins __elision_data.__espins
110# define __elision __elision_data.__eelision
111# endif
112#else
113# define __PTHREAD_SPINS_DATA int __spins
114/* Mutex __spins initializer used by PTHREAD_MUTEX_INITIALIZER. */
115# define __PTHREAD_SPINS 0
116#endif
117
118struct __pthread_mutex_s
119{
120 int __lock __LOCK_ALIGNMENT;
121 unsigned int __count;
122 int __owner;
123#if !__PTHREAD_MUTEX_NUSERS_AFTER_KIND
124 unsigned int __nusers;
125#endif
126 /* KIND must stay at this position in the structure to maintain
127 binary compatibility with static initializers. */
128 int __kind;
129 __PTHREAD_COMPAT_PADDING_MID
130#if __PTHREAD_MUTEX_NUSERS_AFTER_KIND
131 unsigned int __nusers;
132#endif
133#if !__PTHREAD_MUTEX_USE_UNION
134 __PTHREAD_SPINS_DATA;
135 __pthread_list_t __list;
136# define __PTHREAD_MUTEX_HAVE_PREV 1
137#else
138 __extension__ union
139 {
140 __PTHREAD_SPINS_DATA;
141 __pthread_slist_t __list;
142 };
143# define __PTHREAD_MUTEX_HAVE_PREV 0
144#endif
145 __PTHREAD_COMPAT_PADDING_END
146};
147
148
149/* Common definition of pthread_cond_t. */
150
151struct __pthread_cond_s
152{
153 __extension__ union
154 {
155 __extension__ unsigned long long int __wseq;
156 struct
157 {
158 unsigned int __low;
159 unsigned int __high;
160 } __wseq32;
161 };
162 __extension__ union
163 {
164 __extension__ unsigned long long int __g1_start;
165 struct
166 {
167 unsigned int __low;
168 unsigned int __high;
169 } __g1_start32;
170 };
171 unsigned int __g_refs[2] __LOCK_ALIGNMENT;
172 unsigned int __g_size[2];
173 unsigned int __g1_orig_size;
174 unsigned int __wrefs;
175 unsigned int __g_signals[2];
176};
177
178#endif /* _THREAD_SHARED_TYPES_H */
179