generic-library/bionic
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

am 004ecb39: am db1dec1e: Merge "Clean up pthread_internal_t."

Browse Source 
* commit '004ecb39e1cc0aed57b6185d4adf015b61b2d0c6':
  Clean up pthread_internal_t.
This commit is contained in:
Elliott Hughes 2013-11-21 10:12:26 -08:00 committed by Android Git Automerger
commit 0b4ca7e3ce
4 changed files with 19 additions and 18 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
libc/bionic/libc_init_common.cpp
View File

@ -101,9 +101,9 @@ void __libc_init_tls(KernelArgumentBlock& args) {
// environment variables with global scope live on it).
pthread_attr_init(&main_thread.attr);
pthread_attr_setstack(&main_thread.attr, (void*) stack_bottom, stack_size);
main_thread.attr.flags = PTHREAD_ATTR_FLAG_USER_ALLOCATED_STACK;
main_thread.attr.flags = PTHREAD_ATTR_FLAG_USER_ALLOCATED_STACK | PTHREAD_ATTR_FLAG_MAIN_THREAD;
_init_thread(&main_thread, false);
__init_thread(&main_thread, false);
__init_tls(&main_thread);
__set_tls(main_thread.tls);
tls[TLS_SLOT_BIONIC_PREINIT] = &args;
@ -124,7 +124,6 @@ void __libc_init_common(KernelArgumentBlock& args) {
// Get the main thread from TLS and add it to the thread list.
pthread_internal_t* main_thread = __get_thread();
main_thread->allocated_on_heap = false;
_pthread_internal_add(main_thread);
__system_properties_init(); // Requires 'environ'.

23
libc/bionic/pthread_create.cpp
View File

@ -80,7 +80,7 @@ void __init_alternate_signal_stack(pthread_internal_t* thread) {
}
}
int _init_thread(pthread_internal_t* thread, bool add_to_thread_list) {
int __init_thread(pthread_internal_t* thread, bool add_to_thread_list) {
int error = 0;
// Set the scheduling policy/priority of the thread.
@ -148,16 +148,19 @@ static int __pthread_start(void* arg) {
__init_alternate_signal_stack(thread);
if ((thread->internal_flags & PTHREAD_INTERNAL_FLAG_THREAD_INIT_FAILED) != 0) {
pthread_exit(NULL);
}
void* result = thread->start_routine(thread->start_routine_arg);
pthread_exit(result);
return 0;
}
// A dummy start routine for pthread_create failures where we've created a thread but aren't
// going to run user code on it. We swap out the user's start routine for this and take advantage
// of the regular thread teardown to free up resources.
static void* __do_nothing(void*) {
return NULL;
}
int pthread_create(pthread_t* thread_out, pthread_attr_t const* attr,
void* (*start_routine)(void*), void* arg) {
ErrnoRestorer errno_restorer;
@ -174,7 +177,6 @@ int pthread_create(pthread_t* thread_out, pthread_attr_t const* attr,
__libc_format_log(ANDROID_LOG_WARN, "libc", "pthread_create failed: couldn't allocate thread");
return EAGAIN;
}
thread->allocated_on_heap = true;
if (attr == NULL) {
pthread_attr_init(&thread->attr);
@ -238,12 +240,13 @@ int pthread_create(pthread_t* thread_out, pthread_attr_t const* attr,
return clone_errno;
}
int init_errno = _init_thread(thread, true);
int init_errno = __init_thread(thread, true);
if (init_errno != 0) {
// Mark the thread detached and let its __pthread_start run to completion.
// It'll check this flag and exit immediately, cleaning up its resources.
thread->internal_flags |= PTHREAD_INTERNAL_FLAG_THREAD_INIT_FAILED;
// Mark the thread detached and replace its start_routine with a no-op.
// Letting the thread run is the easiest way to clean up its resources.
thread->attr.flags |= PTHREAD_ATTR_FLAG_DETACHED;
thread->start_routine = __do_nothing;
pthread_mutex_unlock(start_mutex);
return init_errno;
}

7
libc/bionic/pthread_internal.h
View File

@ -39,8 +39,6 @@ struct pthread_internal_t {
void** tls;
pthread_attr_t attr;
bool allocated_on_heap; /* TODO: move this into attr.flags? */
int internal_flags; /* TODO: move this into attr.flags? */
__pthread_cleanup_t* cleanup_stack;
@ -58,7 +56,7 @@ struct pthread_internal_t {
char dlerror_buffer[__BIONIC_DLERROR_BUFFER_SIZE];
};
__LIBC_HIDDEN__ int _init_thread(pthread_internal_t* thread, bool add_to_thread_list);
__LIBC_HIDDEN__ int __init_thread(pthread_internal_t* thread, bool add_to_thread_list);
__LIBC_HIDDEN__ void __init_tls(pthread_internal_t* thread);
__LIBC_HIDDEN__ void __init_alternate_signal_stack(pthread_internal_t*);
__LIBC_HIDDEN__ void _pthread_internal_add(pthread_internal_t* thread);
@ -76,7 +74,8 @@ __LIBC_HIDDEN__ void _pthread_internal_remove_locked(pthread_internal_t* thread)
/* Has the thread been joined by another thread? */
#define PTHREAD_ATTR_FLAG_JOINED 0x00000004
#define PTHREAD_INTERNAL_FLAG_THREAD_INIT_FAILED 1
/* Is this the main thread? */
#define PTHREAD_ATTR_FLAG_MAIN_THREAD 0x80000000
/*
* Traditionally we give threads a 1MiB stack. When we started

2
libc/bionic/pthread_internals.cpp
View File

@ -48,7 +48,7 @@ void _pthread_internal_remove_locked(pthread_internal_t* thread) {
// The main thread is not heap-allocated. See __libc_init_tls for the declaration,
// and __libc_init_common for the point where it's added to the thread list.
if (thread->allocated_on_heap) {
if ((thread->attr.flags & PTHREAD_ATTR_FLAG_MAIN_THREAD) == 0) {
free(thread);
}
}