3.13.0b1 freethreading-debug build: flaky test_threaded_weak_valued_setdefault on ppc64le

[befeleme]

Bug report

Bug description:

When building freethreading-debug Python 3.13.0b1 on ppc64le, test.test_weakref.MappingTestCase.test_threaded_weak_valued_setdefault sometimes times out.

test_threaded_weak_valued_setdefault (test.test_weakref.MappingTestCase.test_threaded_weak_valued_setdefault) ... Timeout (0:45:00)!
Thread 0x00007fff96c0f100 (most recent call first):
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/test/test_weakref.py", line 94 in collect
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/threading.py", line 990 in run
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/threading.py", line 1039 in _bootstrap_inner
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/threading.py", line 1010 in _bootstrap
Thread 0x00007fffa6043d00 (most recent call first):
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/weakref.py", line 278 in setdefault
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/test/test_weakref.py", line 1921 in test_threaded_weak_valued_setdefault
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/unittest/case.py", line 606 in _callTestMethod
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/unittest/case.py", line 651 in run
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/unittest/case.py", line 707 in __call__
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/unittest/suite.py", line 122 in run
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/unittest/suite.py", line 84 in __call__
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/unittest/suite.py", line 122 in run
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/unittest/suite.py", line 84 in __call__
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/unittest/runner.py", line 240 in run
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/test/libregrtest/single.py", line 57 in _run_suite
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/test/libregrtest/single.py", line 37 in run_unittest
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/test/libregrtest/single.py", line 132 in test_func
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/test/libregrtest/single.py", line 88 in regrtest_runner
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/test/libregrtest/single.py", line 135 in _load_run_test
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/test/libregrtest/single.py", line 178 in _runtest_env_changed_exc
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/test/libregrtest/single.py", line 278 in _runtest
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/test/libregrtest/single.py", line 309 in run_single_test
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/test/libregrtest/worker.py", line 77 in worker_process
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/test/libregrtest/worker.py", line 112 in main
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/test/libregrtest/worker.py", line 116 in <module>
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/runpy.py", line 88 in _run_code
  File "/builddir/build/BUILD/Python-3.13.0b1/Lib/runpy.py", line 198 in _run_module_as_main

CPython versions tested on:

3.13

Operating systems tested on:

Linux