diff options
Diffstat (limited to 'Lib')
| -rw-r--r-- | Lib/concurrent/futures/thread.py | 1 | ||||
| -rw-r--r-- | Lib/test/test_concurrent_futures/test_thread_pool.py | 19 |
2 files changed, 20 insertions, 0 deletions
diff --git a/Lib/concurrent/futures/thread.py b/Lib/concurrent/futures/thread.py index 16cc553..909359b 100644 --- a/Lib/concurrent/futures/thread.py +++ b/Lib/concurrent/futures/thread.py @@ -41,6 +41,7 @@ if hasattr(os, 'register_at_fork'): os.register_at_fork(before=_global_shutdown_lock.acquire, after_in_child=_global_shutdown_lock._at_fork_reinit, after_in_parent=_global_shutdown_lock.release) + os.register_at_fork(after_in_child=_threads_queues.clear) class WorkerContext: diff --git a/Lib/test/test_concurrent_futures/test_thread_pool.py b/Lib/test/test_concurrent_futures/test_thread_pool.py index 2b5bea9..4324241 100644 --- a/Lib/test/test_concurrent_futures/test_thread_pool.py +++ b/Lib/test/test_concurrent_futures/test_thread_pool.py @@ -66,6 +66,25 @@ class ThreadPoolExecutorTest(ThreadPoolMixin, ExecutorTest, BaseTestCase): with futures.ProcessPoolExecutor(1, mp_context=mp.get_context('fork')) as workers: workers.submit(tuple) + @support.requires_fork() + @unittest.skipUnless(hasattr(os, 'register_at_fork'), 'need os.register_at_fork') + def test_process_fork_from_a_threadpool(self): + # bpo-43944: clear concurrent.futures.thread._threads_queues after fork, + # otherwise child process will try to join parent thread + def fork_process_and_return_exitcode(): + # Ignore the warning about fork with threads. + with self.assertWarnsRegex(DeprecationWarning, + r"use of fork\(\) may lead to deadlocks in the child"): + p = mp.get_context('fork').Process(target=lambda: 1) + p.start() + p.join() + return p.exitcode + + with futures.ThreadPoolExecutor(1) as pool: + process_exitcode = pool.submit(fork_process_and_return_exitcode).result() + + self.assertEqual(process_exitcode, 0) + def test_executor_map_current_future_cancel(self): stop_event = threading.Event() log = [] |