gh-107275 introduced a regression where a SemLock would fail being passed along nested child processes, as the `is_fork_ctx` attribute would be left missing after the first deserialization.
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(cherry picked from commit add8d45cbe)
Co-authored-by: albanD <desmaison.alban@gmail.com>
Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>
Co-authored-by: Antoine Pitrou <pitrou@free.fr>
gh-77377: Ensure multiprocessing SemLock is valid for spawn-based Process before serializing it (GH-107275)
Ensure multiprocessing SemLock is valid for spawn Process before serializing it.
Creating a multiprocessing SemLock with a fork context, and then trying to pass it to a spawn-created Process, would segfault if not detected early.
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(cherry picked from commit 1700d34d31)
Co-authored-by: albanD <desmaison.alban@gmail.com>
Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>
Co-authored-by: Antoine Pitrou <pitrou@free.fr>
gh-107963: Fix set_forkserver_preload to check the type of given list (GH-107965)
(cherry picked from commit 6515ec3d3d)
gh-107963: Fix set_forkserver_preload to check the type of given list
Co-authored-by: Dong-hee Na <donghee.na@python.org>
gh-90876: Restore the ability to import multiprocessing when `sys.executable` is `None` (GH-106464)
Prevent `multiprocessing.spawn` from failing to *import* in environments
where `sys.executable` is `None`. This regressed in 3.11 with the addition
of support for path-like objects in multiprocessing.
Adds a test decorator to have tests only run when part of test_multiprocessing_spawn to `_test_multiprocessing.py` so we can start to avoid re-running the same not-global-state specific test in all 3 modes when there is no need.
(cherry picked from commit c60df361ce)
Co-authored-by: Gregory P. Smith <greg@krypto.org>
Add an optional keyword 'shutdown_timeout' parameter to the
multiprocessing.BaseManager constructor. Kill the process if
terminate() takes longer than the timeout.
Multiprocessing tests pass test.support.SHORT_TIMEOUT
to BaseManager.shutdown_timeout.
Skip tests on ASAN and/or MSAN builds:
* multiprocessing tests
* test___all__
* test_concurrent_futures
* test_decimal
* test_peg_generator
* test_tools
The ASAN job of GitHub Actions no longer excludes these tests.
For threads, and for multiprocessing, it's always been the case that ``args=list`` works fine when passed to ``Process()`` or ``Thread()``, and such code is common in the wild. But, according to the docs, only a tuple can be used. This brings the docs into synch with reality.
Doc changes by Charlie Zhao.
Co-authored-by: Tim Peters <tim.peters@gmail.com>
Add a PID to names of POSIX shared memory objects to allow
running multiprocessing tests (test_multiprocessing_fork,
test_multiprocessing_spawn, etc) in parallel.
On Linux, skip tests using multiprocessing if the current user cannot
create a file in /dev/shm/ directory. Add the
skip_if_broken_multiprocessing_synchronize() function to the
test.support module.
* Move socket related functions from test.support to socket_helper.
* Import socket, nntplib and urllib.error lazily in transient_internet().
* Remove importing multiprocess.
Log "Warning -- ..." test warnings into sys.__stderr__ rather than
sys.stderr, to ensure to display them even if sys.stderr is captured.
test.libregrtest.utils.print_warning() now calls
test.support.print_warning().
Moreover, the following tests now check the child process exit code:
* test_os.PtyTests
* test_mailbox.test_lock_conflict()
* test_tempfile.test_process_awareness()
* test_uuid.testIssue8621()
* multiprocessing resource tracker tests
When the pull is not used via the context manager or terminate() is called, there is a system in multiprocessing.util that handles finalization of all pools via an atexit handler (the Finalize) class. This class registers the _terminate_pool handler in the registry of finalizers of the module, and that registry is called on interpreter exit via _exit_function. The problem is that the "happy" path with the context manager or manual call to finalize() does some extra steps that _terminate_pool does not. The step that is not executed when the atexit() handler calls _terminate_pool is pinging the _change_notifier queue to unblock the maintenance threads.
This commit moves the notification to the _terminate_pool function so is called from both code paths.
Co-authored-by: Pablo Galindo <Pablogsal@gmail.com>
Multiprocessing and concurrent.futures tests now stop the resource
tracker process when tests complete.
Add ResourceTracker._stop() method to
multiprocessing.resource_tracker.
Add _cleanup_tests() helper function to multiprocessing.util: share
code between multiprocessing and concurrent.futures tests.
Replace hardcoded timeout constants in tests with SHORT_TIMEOUT of
test.support, so it's easier to ajdust this timeout for all tests at
once.
SHORT_TIMEOUT is 30 seconds by default, but it can be longer
depending on --timeout command line option.
The change makes almost all timeouts longer, except
test_reap_children() of test_support which is made 2x shorter:
SHORT_TIMEOUT should be enough. If this test starts to fail,
LONG_TIMEOUT should be used instead.
Uniformize also "from test import support" import in some test files.
Replace hardcoded timeout constants in tests with LONG_TIMEOUT of
test.support, so it's easier to ajdust this timeout for all tests at
once.
LONG_TIMEOUT is 5 minutes by default, but it can be longer depending
on --timeout command line option.
This PR implements a fix for `multiprocessing.Process` objects; the error occurs when Processes are created using either `fork` or `forkserver` as the `start_method`.
In these instances, the `MainThread` of the newly created `Process` object retains all attributes from its parent's `MainThread` object, including the `native_id` attribute. The resulting behavior is such that the new process' `MainThread` captures an incorrect/outdated `native_id` (the parent's instead of its own).
This change forces the Process object to update its `native_id` attribute during the bootstrap process.
cc @vstinner
https://bugs.python.org/issue38707
Automerge-Triggered-By: @pitrou