Home | History | Annotate | Download | only in bionic 
      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_tls.h"
     35 
     36 /* Has the thread been detached by a pthread_join or pthread_detach call? */
     37 #define PTHREAD_ATTR_FLAG_DETACHED 0x00000001
     38 
     39 /* Has the thread been joined by another thread? */
     40 #define PTHREAD_ATTR_FLAG_JOINED 0x00000002
     41 
     42 struct pthread_key_data_t {
     43   uintptr_t seq; // Use uintptr_t just for alignment, as we use pointer below.
     44   void* data;
     45 };
     46 
     47 enum ThreadJoinState {
     48   THREAD_NOT_JOINED,
     49   THREAD_EXITED_NOT_JOINED,
     50   THREAD_JOINED,
     51   THREAD_DETACHED
     52 };
     53 
     54 struct pthread_internal_t {
     55   struct pthread_internal_t* next;
     56   struct pthread_internal_t* prev;
     57 
     58   pid_t tid;
     59 
     60  private:
     61   pid_t cached_pid_;
     62 
     63  public:
     64   pid_t invalidate_cached_pid() {
     65     pid_t old_value;
     66     get_cached_pid(&old_value);
     67     set_cached_pid(0);
     68     return old_value;
     69   }
     70 
     71   void set_cached_pid(pid_t value) {
     72     cached_pid_ = value;
     73   }
     74 
     75   bool get_cached_pid(pid_t* cached_pid) {
     76     *cached_pid = cached_pid_;
     77     return (*cached_pid != 0);
     78   }
     79 
     80   pthread_attr_t attr;
     81 
     82   _Atomic(ThreadJoinState) join_state;
     83 
     84   __pthread_cleanup_t* cleanup_stack;
     85 
     86   void* (*start_routine)(void*);
     87   void* start_routine_arg;
     88   void* return_value;
     89 
     90   void* alternate_signal_stack;
     91 
     92   pthread_mutex_t startup_handshake_mutex;
     93 
     94   size_t mmap_size;
     95 
     96   void* tls[BIONIC_TLS_SLOTS];
     97 
     98   pthread_key_data_t key_data[BIONIC_PTHREAD_KEY_COUNT];
     99 
    100   /*
    101    * The dynamic linker implements dlerror(3), which makes it hard for us to implement this
    102    * per-thread buffer by simply using malloc(3) and free(3).
    103    */
    104 #define __BIONIC_DLERROR_BUFFER_SIZE 512
    105   char dlerror_buffer[__BIONIC_DLERROR_BUFFER_SIZE];
    106 };
    107 
    108 __LIBC_HIDDEN__ int __init_thread(pthread_internal_t* thread);
    109 __LIBC_HIDDEN__ void __init_tls(pthread_internal_t* thread);
    110 __LIBC_HIDDEN__ void __init_alternate_signal_stack(pthread_internal_t*);
    111 
    112 __LIBC_HIDDEN__ pthread_t           __pthread_internal_add(pthread_internal_t* thread);
    113 __LIBC_HIDDEN__ pthread_internal_t* __pthread_internal_find(pthread_t pthread_id);
    114 __LIBC_HIDDEN__ void                __pthread_internal_remove(pthread_internal_t* thread);
    115 __LIBC_HIDDEN__ void                __pthread_internal_remove_and_free(pthread_internal_t* thread);
    116 
    117 // Make __get_thread() inlined for performance reason. See http://b/19825434.
    118 static inline __always_inline pthread_internal_t* __get_thread() {
    119   return reinterpret_cast<pthread_internal_t*>(__get_tls()[TLS_SLOT_THREAD_ID]);
    120 }
    121 
    122 __LIBC_HIDDEN__ void pthread_key_clean_all(void);
    123 
    124 /*
    125  * Traditionally we gave threads a 1MiB stack. When we started
    126  * allocating per-thread alternate signal stacks to ease debugging of
    127  * stack overflows, we subtracted the same amount we were using there
    128  * from the default thread stack size. This should keep memory usage
    129  * roughly constant.
    130  */
    131 #define PTHREAD_STACK_SIZE_DEFAULT ((1 * 1024 * 1024) - SIGSTKSZ)
    132 
    133 /* Leave room for a guard page in the internally created signal stacks. */
    134 #define SIGNAL_STACK_SIZE (SIGSTKSZ + PAGE_SIZE)
    135 
    136 /* Needed by fork. */
    137 __LIBC_HIDDEN__ extern void __bionic_atfork_run_prepare();
    138 __LIBC_HIDDEN__ extern void __bionic_atfork_run_child();
    139 __LIBC_HIDDEN__ extern void __bionic_atfork_run_parent();
    140 
    141 #endif /* _PTHREAD_INTERNAL_H_ */
    142