pthread_internal.h revision 8cf1b305670123aed7638d984ca39bfd22388440 
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
33#include "private/bionic_tls.h"
34
35/* Has the thread been detached by a pthread_join or pthread_detach call? */
36#define PTHREAD_ATTR_FLAG_DETACHED 0x00000001
37
38/* Was the thread's stack allocated by the user rather than by us? */
39#define PTHREAD_ATTR_FLAG_USER_ALLOCATED_STACK 0x00000002
40
41/* Has the thread been joined by another thread? */
42#define PTHREAD_ATTR_FLAG_JOINED 0x00000004
43
44/* Is this the main thread? */
45#define PTHREAD_ATTR_FLAG_MAIN_THREAD 0x80000000
46
47struct pthread_internal_t {
48  struct pthread_internal_t* next;
49  struct pthread_internal_t* prev;
50
51  pid_t tid;
52
53 private:
54  pid_t cached_pid_;
55
56 public:
57  pid_t invalidate_cached_pid() {
58    pid_t old_value;
59    get_cached_pid(&old_value);
60    set_cached_pid(0);
61    return old_value;
62  }
63
64  void set_cached_pid(pid_t value) {
65    cached_pid_ = value;
66  }
67
68  bool get_cached_pid(pid_t* cached_pid) {
69    *cached_pid = cached_pid_;
70    return (*cached_pid != 0);
71  }
72
73  bool user_allocated_stack() {
74    return (attr.flags & PTHREAD_ATTR_FLAG_USER_ALLOCATED_STACK) != 0;
75  }
76
77  pthread_attr_t attr;
78
79  __pthread_cleanup_t* cleanup_stack;
80
81  void* (*start_routine)(void*);
82  void* start_routine_arg;
83  void* return_value;
84
85  void* alternate_signal_stack;
86
87  pthread_mutex_t startup_handshake_mutex;
88
89  void* tls[BIONIC_TLS_SLOTS];
90
91  /*
92   * The dynamic linker implements dlerror(3), which makes it hard for us to implement this
93   * per-thread buffer by simply using malloc(3) and free(3).
94   */
95#define __BIONIC_DLERROR_BUFFER_SIZE 512
96  char dlerror_buffer[__BIONIC_DLERROR_BUFFER_SIZE];
97} __attribute__((aligned(16))); // Align it as thread stack top below it should be aligned.
98
99__LIBC_HIDDEN__ int __init_thread(pthread_internal_t* thread, bool add_to_thread_list);
100__LIBC_HIDDEN__ void __init_tls(pthread_internal_t* thread);
101__LIBC_HIDDEN__ void __init_alternate_signal_stack(pthread_internal_t*);
102__LIBC_HIDDEN__ void _pthread_internal_add(pthread_internal_t* thread);
103
104/* Various third-party apps contain a backport of our pthread_rwlock implementation that uses this. */
105extern "C" __LIBC64_HIDDEN__ pthread_internal_t* __get_thread(void);
106
107__LIBC_HIDDEN__ void pthread_key_clean_all(void);
108__LIBC_HIDDEN__ void _pthread_internal_remove_locked(pthread_internal_t* thread, bool free_thread);
109
110/*
111 * Traditionally we gave threads a 1MiB stack. When we started
112 * allocating per-thread alternate signal stacks to ease debugging of
113 * stack overflows, we subtracted the same amount we were using there
114 * from the default thread stack size. This should keep memory usage
115 * roughly constant.
116 */
117#define PTHREAD_STACK_SIZE_DEFAULT ((1 * 1024 * 1024) - SIGSTKSZ)
118
119__LIBC_HIDDEN__ extern pthread_internal_t* g_thread_list;
120__LIBC_HIDDEN__ extern pthread_mutex_t g_thread_list_lock;
121
122/* Needed by fork. */
123__LIBC_HIDDEN__ extern void __bionic_atfork_run_prepare();
124__LIBC_HIDDEN__ extern void __bionic_atfork_run_child();
125__LIBC_HIDDEN__ extern void __bionic_atfork_run_parent();
126
127#endif /* _PTHREAD_INTERNAL_H_ */
128