mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-09-27 02:39:58 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 13

Issue #18808 again: fix the after-fork logic for not-yet-started or already-stopped threads.

Browse source 
(AFAICT, in theory, we must reset all the locks, not just those in use)
This commit is contained in:
Antoine Pitrou 2013-09-08 13:19:06 +02:00
parent 6f6f4865d1
commit 5da7e7959e
2 changed files with 8 additions and 10 deletions
Download patch file Download diff file Expand all files Collapse all files

2
Lib/test/test_threading.py
View file

@ -109,7 +109,7 @@ class ThreadTests(BaseTestCase):
if verbose: if verbose:
print('waiting for all tasks to complete') print('waiting for all tasks to complete')
for t in threads: for t in threads:
t.join(NUMTASKS) t.join()
self.assertTrue(not t.is_alive()) self.assertTrue(not t.is_alive())
self.assertNotEqual(t.ident, 0) self.assertNotEqual(t.ident, 0)
self.assertFalse(t.ident is None) self.assertFalse(t.ident is None)

16
Lib/threading.py
View file

@ -517,8 +517,6 @@ def _newname(template="Thread-%d"):
_active_limbo_lock = _allocate_lock() _active_limbo_lock = _allocate_lock()
_active = {} # maps thread id to Thread object _active = {} # maps thread id to Thread object
_limbo = {} _limbo = {}
# For debug and leak testing
_dangling = WeakSet() _dangling = WeakSet()
# Main class for threads # Main class for threads
@ -552,14 +550,11 @@ class Thread:
self._tstate_lock = None self._tstate_lock = None
self._started = Event() self._started = Event()
self._stopped = Event() self._stopped = Event()
# _is_stopped should be the same as _stopped.is_set(). The bizarre
# duplication is to allow test_is_alive_after_fork to pass on old
# Linux kernels. See issue 18808.
self._is_stopped = False
self._initialized = True self._initialized = True
# sys.stderr is not stored in the class like # sys.stderr is not stored in the class like
# sys.exc_info since it can be changed between instances # sys.exc_info since it can be changed between instances
self._stderr = _sys.stderr self._stderr = _sys.stderr
# For debugging and _after_fork()
_dangling.add(self) _dangling.add(self)
def _reset_internal_locks(self, is_alive): def _reset_internal_locks(self, is_alive):
@ -711,7 +706,6 @@ class Thread:
def _stop(self): def _stop(self):
self._stopped.set() self._stopped.set()
self._is_stopped = True
def _delete(self): def _delete(self):
"Remove current thread from the dict of currently running threads." "Remove current thread from the dict of currently running threads."
@ -798,7 +792,7 @@ class Thread:
assert self._initialized, "Thread.__init__() not called" assert self._initialized, "Thread.__init__() not called"
if not self._started.is_set(): if not self._started.is_set():
return False return False
if not self._is_stopped: if not self._stopped.is_set():
return True return True
# The Python part of the thread is done, but the C part may still be # The Python part of the thread is done, but the C part may still be
# waiting to run. # waiting to run.
@ -976,7 +970,11 @@ def _after_fork():
current = current_thread() current = current_thread()
_main_thread = current _main_thread = current
with _active_limbo_lock: with _active_limbo_lock:
for thread in _enumerate(): # Dangling thread instances must still have their locks reset,
# because someone may join() them.
threads = set(_enumerate())
threads.update(_dangling)
for thread in threads:
# Any lock/condition variable may be currently locked or in an # Any lock/condition variable may be currently locked or in an
# invalid state, so we reinitialize them. # invalid state, so we reinitialize them.
if thread is current: if thread is current: