https://github.com/python/cpython/commit/c3955e049fd5dbd3d92bc95fed4442964156293d commit: c3955e049fd5dbd3d92bc95fed4442964156293d branch: main author: Thomas Kowalski <[email protected]> committer: kumaraditya303 <[email protected]> date: 2026-03-11T12:57:26+05:30 summary:
gh-145713: make bytearray.resize thread-safe on free-threading (#145714) Co-authored-by: Kumar Aditya <[email protected]> files: A Misc/NEWS.d/next/Core_and_Builtins/2026-03-09-00-00-00.gh-issue-145713.KR6azvzI.rst M Lib/test/test_bytes.py M Objects/bytearrayobject.c M Objects/clinic/bytearrayobject.c.h diff --git a/Lib/test/test_bytes.py b/Lib/test/test_bytes.py index 1c64bf888f9d27..876ecd4467b0a2 100644 --- a/Lib/test/test_bytes.py +++ b/Lib/test/test_bytes.py @@ -2908,6 +2908,22 @@ def check(funcs, it): check([iter_next] + [iter_reduce] * 10, iter(ba)) # for tsan check([iter_next] + [iter_setstate] * 10, iter(ba)) # for tsan + @unittest.skipUnless(support.Py_GIL_DISABLED, 'this test can only possibly fail with GIL disabled') + @threading_helper.reap_threads + @threading_helper.requires_working_threading() + def test_free_threading_bytearray_resize(self): + def resize_stress(ba): + for _ in range(1000): + try: + ba.resize(1000) + ba.resize(1) + except (BufferError, ValueError): + pass + + ba = bytearray(100) + threads = [threading.Thread(target=resize_stress, args=(ba,)) for _ in range(4)] + with threading_helper.start_threads(threads): + pass if __name__ == "__main__": unittest.main() diff --git a/Misc/NEWS.d/next/Core_and_Builtins/2026-03-09-00-00-00.gh-issue-145713.KR6azvzI.rst b/Misc/NEWS.d/next/Core_and_Builtins/2026-03-09-00-00-00.gh-issue-145713.KR6azvzI.rst new file mode 100644 index 00000000000000..2cf83eff31056a --- /dev/null +++ b/Misc/NEWS.d/next/Core_and_Builtins/2026-03-09-00-00-00.gh-issue-145713.KR6azvzI.rst @@ -0,0 +1,3 @@ +Make :meth:`bytearray.resize` thread-safe in the free-threaded build by +using a critical section and calling the lock-held variant of the resize +function. diff --git a/Objects/bytearrayobject.c b/Objects/bytearrayobject.c index 7f09769e12f05f..e2fea94e099626 100644 --- a/Objects/bytearrayobject.c +++ b/Objects/bytearrayobject.c @@ -1506,6 +1506,7 @@ bytearray_removesuffix_impl(PyByteArrayObject *self, Py_buffer *suffix) /*[clinic input] +@critical_section bytearray.resize size: Py_ssize_t New size to resize to. @@ -1515,10 +1516,10 @@ Resize the internal buffer of bytearray to len. static PyObject * bytearray_resize_impl(PyByteArrayObject *self, Py_ssize_t size) -/*[clinic end generated code: output=f73524922990b2d9 input=6c9a260ca7f72071]*/ +/*[clinic end generated code: output=f73524922990b2d9 input=116046316a2b5cfc]*/ { Py_ssize_t start_size = PyByteArray_GET_SIZE(self); - int result = PyByteArray_Resize((PyObject *)self, size); + int result = bytearray_resize_lock_held((PyObject *)self, size); if (result < 0) { return NULL; } diff --git a/Objects/clinic/bytearrayobject.c.h b/Objects/clinic/bytearrayobject.c.h index be704ccf68f669..cf60d0ceadc7d1 100644 --- a/Objects/clinic/bytearrayobject.c.h +++ b/Objects/clinic/bytearrayobject.c.h @@ -625,7 +625,9 @@ bytearray_resize(PyObject *self, PyObject *arg) } size = ival; } + Py_BEGIN_CRITICAL_SECTION(self); return_value = bytearray_resize_impl((PyByteArrayObject *)self, size); + Py_END_CRITICAL_SECTION(); exit: return return_value; @@ -1833,4 +1835,4 @@ bytearray_sizeof(PyObject *self, PyObject *Py_UNUSED(ignored)) { return bytearray_sizeof_impl((PyByteArrayObject *)self); } -/*[clinic end generated code: output=5eddefde2a001ceb input=a9049054013a1b77]*/ +/*[clinic end generated code: output=2d76ef023928424f input=a9049054013a1b77]*/ _______________________________________________ Python-checkins mailing list -- [email protected] To unsubscribe send an email to [email protected] https://mail.python.org/mailman3//lists/python-checkins.python.org Member address: [email protected]
