1/*
2 * Copyright (C) 2008 The Android Open Source Project
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *  * Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 *  * Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in
12 *    the documentation and/or other materials provided with the
13 *    distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28#ifndef _PTHREAD_INTERNAL_H_
29#define _PTHREAD_INTERNAL_H_
30
31#include <pthread.h>
32#include <stdatomic.h>
33
34#include "private/bionic_lock.h"
35#include "private/bionic_tls.h"
36
37/* Has the thread been detached by a pthread_join or pthread_detach call? */
38#define PTHREAD_ATTR_FLAG_DETACHED 0x00000001
39
40/* Has the thread been joined by another thread? */
41#define PTHREAD_ATTR_FLAG_JOINED 0x00000002
42
43class pthread_key_data_t {
44 public:
45  uintptr_t seq; // Use uintptr_t just for alignment, as we use pointer below.
46  void* data;
47};
48
49enum ThreadJoinState {
50  THREAD_NOT_JOINED,
51  THREAD_EXITED_NOT_JOINED,
52  THREAD_JOINED,
53  THREAD_DETACHED
54};
55
56class thread_local_dtor;
57
58class pthread_internal_t {
59 public:
60  class pthread_internal_t* next;
61  class pthread_internal_t* prev;
62
63  pid_t tid;
64
65 private:
66  pid_t cached_pid_;
67
68 public:
69  pid_t invalidate_cached_pid() {
70    pid_t old_value;
71    get_cached_pid(&old_value);
72    set_cached_pid(0);
73    return old_value;
74  }
75
76  void set_cached_pid(pid_t value) {
77    cached_pid_ = value;
78  }
79
80  bool get_cached_pid(pid_t* cached_pid) {
81    *cached_pid = cached_pid_;
82    return (*cached_pid != 0);
83  }
84
85  pthread_attr_t attr;
86
87  _Atomic(ThreadJoinState) join_state;
88
89  __pthread_cleanup_t* cleanup_stack;
90
91  void* (*start_routine)(void*);
92  void* start_routine_arg;
93  void* return_value;
94
95  void* alternate_signal_stack;
96
97  Lock startup_handshake_lock;
98
99  size_t mmap_size;
100
101  thread_local_dtor* thread_local_dtors;
102
103  void* tls[BIONIC_TLS_SLOTS];
104
105  pthread_key_data_t key_data[BIONIC_PTHREAD_KEY_COUNT];
106
107  /*
108   * The dynamic linker implements dlerror(3), which makes it hard for us to implement this
109   * per-thread buffer by simply using malloc(3) and free(3).
110   */
111#define __BIONIC_DLERROR_BUFFER_SIZE 512
112  char dlerror_buffer[__BIONIC_DLERROR_BUFFER_SIZE];
113};
114
115__LIBC_HIDDEN__ int __init_thread(pthread_internal_t* thread);
116__LIBC_HIDDEN__ void __init_tls(pthread_internal_t* thread);
117__LIBC_HIDDEN__ void __init_alternate_signal_stack(pthread_internal_t*);
118
119__LIBC_HIDDEN__ pthread_t           __pthread_internal_add(pthread_internal_t* thread);
120__LIBC_HIDDEN__ pthread_internal_t* __pthread_internal_find(pthread_t pthread_id);
121__LIBC_HIDDEN__ void                __pthread_internal_remove(pthread_internal_t* thread);
122__LIBC_HIDDEN__ void                __pthread_internal_remove_and_free(pthread_internal_t* thread);
123
124// Make __get_thread() inlined for performance reason. See http://b/19825434.
125static inline __always_inline pthread_internal_t* __get_thread() {
126  return reinterpret_cast<pthread_internal_t*>(__get_tls()[TLS_SLOT_THREAD_ID]);
127}
128
129__LIBC_HIDDEN__ void pthread_key_clean_all(void);
130
131/*
132 * Traditionally we gave threads a 1MiB stack. When we started
133 * allocating per-thread alternate signal stacks to ease debugging of
134 * stack overflows, we subtracted the same amount we were using there
135 * from the default thread stack size. This should keep memory usage
136 * roughly constant.
137 */
138#define PTHREAD_STACK_SIZE_DEFAULT ((1 * 1024 * 1024) - SIGSTKSZ)
139
140// Leave room for a guard page in the internally created signal stacks.
141#if defined(__LP64__)
142// SIGSTKSZ is not big enough for 64-bit arch. See http://b/23041777.
143#define SIGNAL_STACK_SIZE (16 * 1024 + PAGE_SIZE)
144#else
145#define SIGNAL_STACK_SIZE (SIGSTKSZ + PAGE_SIZE)
146#endif
147
148/* Needed by fork. */
149__LIBC_HIDDEN__ extern void __bionic_atfork_run_prepare();
150__LIBC_HIDDEN__ extern void __bionic_atfork_run_child();
151__LIBC_HIDDEN__ extern void __bionic_atfork_run_parent();
152
153#endif /* _PTHREAD_INTERNAL_H_ */
154