platform_bionic/libc/bionic/pthread_internal.cpp
Yabin Cui 673b15e4ee Let g_thread_list_lock only protect g_thread_list.
As glibc/netbsd don't protect access to thread struct members by a global
lock, we don't want to do it either. This change reduces the
responsibility of g_thread_list_lock to only protect g_thread_list.

Bug: 19636317
Change-Id: I897890710653dac165d8fa4452c7ecf74abdbf2b
2015-03-23 19:03:49 -07:00

92 lines
3.1 KiB
C++

/*
* Copyright (C) 2008 The Android Open Source Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include "pthread_internal.h"
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mman.h>
#include "private/bionic_futex.h"
#include "private/bionic_tls.h"
#include "private/libc_logging.h"
#include "private/ScopedPthreadMutexLocker.h"
static pthread_internal_t* g_thread_list = NULL;
static pthread_mutex_t g_thread_list_lock = PTHREAD_MUTEX_INITIALIZER;
pthread_t __pthread_internal_add(pthread_internal_t* thread) {
ScopedPthreadMutexLocker locker(&g_thread_list_lock);
// We insert at the head.
thread->next = g_thread_list;
thread->prev = NULL;
if (thread->next != NULL) {
thread->next->prev = thread;
}
g_thread_list = thread;
return reinterpret_cast<pthread_t>(thread);
}
void __pthread_internal_remove(pthread_internal_t* thread) {
ScopedPthreadMutexLocker locker(&g_thread_list_lock);
if (thread->next != NULL) {
thread->next->prev = thread->prev;
}
if (thread->prev != NULL) {
thread->prev->next = thread->next;
} else {
g_thread_list = thread->next;
}
}
static void __pthread_internal_free(pthread_internal_t* thread) {
if (thread->mmap_size != 0) {
// Free mapped space, including thread stack and pthread_internal_t.
munmap(thread->attr.stack_base, thread->mmap_size);
}
}
void __pthread_internal_remove_and_free(pthread_internal_t* thread) {
__pthread_internal_remove(thread);
__pthread_internal_free(thread);
}
pthread_internal_t* __pthread_internal_find(pthread_t thread_id) {
pthread_internal_t* thread = reinterpret_cast<pthread_internal_t*>(thread_id);
ScopedPthreadMutexLocker locker(&g_thread_list_lock);
for (pthread_internal_t* t = g_thread_list; t != NULL; t = t->next) {
if (t == thread) {
return thread;
}
}
return NULL;
}