mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-09-04 07:51:13 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 10

bpo-33608: Minor cleanup related to pending calls. (gh-12247)

Browse source
This commit is contained in:
Eric Snow 2019-03-08 22:47:07 -07:00 • committed by GitHub
parent 7bda9de550
commit 5be45a6105
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
5 changed files with 81 additions and 68 deletions
Download patch file Download diff file Expand all files Collapse all files

80
Python/ceval.c
View file

@ -174,9 +174,11 @@ PyEval_InitThreads(void)
PyThread_init_thread();
create_gil();
take_gil(_PyThreadState_GET());
_PyRuntime.ceval.pending.main_thread = PyThread_get_thread_ident();
if (!_PyRuntime.ceval.pending.lock)
// Set it to the ID of the main thread of the main interpreter.
_PyRuntime.main_thread = PyThread_get_thread_ident();
if (!_PyRuntime.ceval.pending.lock) {
_PyRuntime.ceval.pending.lock = PyThread_allocate_lock();
}
}
void
@ -243,9 +245,9 @@ PyEval_ReInitThreads(void)
if (!gil_created())
return;
recreate_gil();
_PyRuntime.ceval.pending.lock = PyThread_allocate_lock();
take_gil(current_tstate);
_PyRuntime.ceval.pending.main_thread = PyThread_get_thread_ident();
_PyRuntime.main_thread = PyThread_get_thread_ident();
_PyRuntime.ceval.pending.lock = PyThread_allocate_lock();
/* Destroy all threads except the current one */
_PyThreadState_DeleteExcept(current_tstate);
@ -323,6 +325,35 @@ _PyEval_SignalReceived(void)
SIGNAL_PENDING_SIGNALS();
}
/* Push one item onto the queue while holding the lock. */
static int
_push_pending_call(int (*func)(void *), void *arg)
{
int i = _PyRuntime.ceval.pending.last;
int j = (i + 1) % NPENDINGCALLS;
if (j == _PyRuntime.ceval.pending.first) {
return -1; /* Queue full */
}
_PyRuntime.ceval.pending.calls[i].func = func;
_PyRuntime.ceval.pending.calls[i].arg = arg;
_PyRuntime.ceval.pending.last = j;
return 0;
}
/* Pop one item off the queue while holding the lock. */
static void
_pop_pending_call(int (**func)(void *), void **arg)
{
int i = _PyRuntime.ceval.pending.first;
if (i == _PyRuntime.ceval.pending.last) {
return; /* Queue empty */
}
*func = _PyRuntime.ceval.pending.calls[i].func;
*arg = _PyRuntime.ceval.pending.calls[i].arg;
_PyRuntime.ceval.pending.first = (i + 1) % NPENDINGCALLS;
}
/* This implementation is thread-safe. It allows
scheduling to be made from any thread, and even from an executing
callback.
@ -331,7 +362,6 @@ _PyEval_SignalReceived(void)
int
Py_AddPendingCall(int (*func)(void *), void *arg)
{
int i, j, result=0;
PyThread_type_lock lock = _PyRuntime.ceval.pending.lock;
/* try a few times for the lock. Since this mechanism is used
@ -346,6 +376,7 @@ Py_AddPendingCall(int (*func)(void *), void *arg)
* this function is called before any bytecode evaluation takes place.
*/
if (lock != NULL) {
int i;
for (i = 0; i<100; i++) {
if (PyThread_acquire_lock(lock, NOWAIT_LOCK))
break;
@ -354,15 +385,8 @@ Py_AddPendingCall(int (*func)(void *), void *arg)
return -1;
}
i = _PyRuntime.ceval.pending.last;
j = (i + 1) % NPENDINGCALLS;
if (j == _PyRuntime.ceval.pending.first) {
result = -1; /* Queue full */
} else {
_PyRuntime.ceval.pending.calls[i].func = func;
_PyRuntime.ceval.pending.calls[i].arg = arg;
_PyRuntime.ceval.pending.last = j;
}
int result = _push_pending_call(func, arg);
/* signal main loop */
SIGNAL_PENDING_CALLS();
if (lock != NULL)
@ -373,10 +397,10 @@ Py_AddPendingCall(int (*func)(void *), void *arg)
static int
handle_signals(void)
{
/* Only handle signals on main thread. */
if (_PyRuntime.ceval.pending.main_thread &&
PyThread_get_thread_ident() != _PyRuntime.ceval.pending.main_thread)
{
/* Only handle signals on main thread. PyEval_InitThreads must
* have been called already.
*/
if (PyThread_get_thread_ident() != _PyRuntime.main_thread) {
return 0;
}
/*
@ -401,9 +425,7 @@ make_pending_calls(void)
static int busy = 0;
/* only service pending calls on main thread */
if (_PyRuntime.ceval.pending.main_thread &&
PyThread_get_thread_ident() != _PyRuntime.ceval.pending.main_thread)
{
if (PyThread_get_thread_ident() != _PyRuntime.main_thread) {
return 0;
}
@ -428,24 +450,18 @@ make_pending_calls(void)
/* perform a bounded number of calls, in case of recursion */
for (int i=0; i<NPENDINGCALLS; i++) {
int j;
int (*func)(void *);
int (*func)(void *) = NULL;
void *arg = NULL;
/* pop one item off the queue while holding the lock */
PyThread_acquire_lock(_PyRuntime.ceval.pending.lock, WAIT_LOCK);
j = _PyRuntime.ceval.pending.first;
if (j == _PyRuntime.ceval.pending.last) {
func = NULL; /* Queue empty */
} else {
func = _PyRuntime.ceval.pending.calls[j].func;
arg = _PyRuntime.ceval.pending.calls[j].arg;
_PyRuntime.ceval.pending.first = (j + 1) % NPENDINGCALLS;
}
_pop_pending_call(&func, &arg);
PyThread_release_lock(_PyRuntime.ceval.pending.lock);
/* having released the lock, perform the callback */
if (func == NULL)
if (func == NULL) {
break;
}
res = func(arg);
if (res) {
goto error;