https://github.com/python/cpython/commit/44ba11a2045a8d00b6089fedd8b57f02c8a... commit: 44ba11a2045a8d00b6089fedd8b57f02c8a7225a branch: 3.13 author: Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com> committer: Yhg1s <thomas@python.org> date: 2024-09-30T13:51:24-07:00 summary: [3.13] gh-124642: Dictionaries aren't marking objects as weakref'd (GH-124643) (#124798) gh-124642: Dictionaries aren't marking objects as weakref'd (GH-124643) Dictionaries aren't marking objects as weakref'd (cherry picked from commit 077e7ef6a0abbf9e04b9aa11b4f621031004c31f) Co-authored-by: Dino Viehland <dinoviehland@meta.com> files: A Misc/NEWS.d/next/Core_and_Builtins/2024-09-27-17-18-53.gh-issue-124642.OCjhBJ.rst M Objects/dictobject.c diff --git a/Misc/NEWS.d/next/Core_and_Builtins/2024-09-27-17-18-53.gh-issue-124642.OCjhBJ.rst b/Misc/NEWS.d/next/Core_and_Builtins/2024-09-27-17-18-53.gh-issue-124642.OCjhBJ.rst new file mode 100644 index 00000000000000..29763844a9f592 --- /dev/null +++ b/Misc/NEWS.d/next/Core_and_Builtins/2024-09-27-17-18-53.gh-issue-124642.OCjhBJ.rst @@ -0,0 +1 @@ +Fixed scalability issue in free-threaded builds for lock-free reads from dictionaries in multi-threaded scenarios diff --git a/Objects/dictobject.c b/Objects/dictobject.c index 7f7fd836c01509..a5a5bce3965555 100644 --- a/Objects/dictobject.c +++ b/Objects/dictobject.c @@ -1549,7 +1549,7 @@ _Py_dict_lookup_threadsafe(PyDictObject *mp, PyObject *key, Py_hash_t hash, PyOb *value_addr = value; if (value != NULL) { assert(ix >= 0); - Py_INCREF(value); + _Py_NewRefWithLock(value); } Py_END_CRITICAL_SECTION(); return ix; @@ -6988,7 +6988,7 @@ _PyObject_TryGetInstanceAttribute(PyObject *obj, PyObject *name, PyObject **attr // Still no dict, we can read from the values assert(values->valid); value = values->values[ix]; - *attr = Py_XNewRef(value); + *attr = _Py_XNewRefWithLock(value); success = true; } @@ -7008,7 +7008,7 @@ _PyObject_TryGetInstanceAttribute(PyObject *obj, PyObject *name, PyObject **attr if (dict->ma_values == values && FT_ATOMIC_LOAD_UINT8(values->valid)) { value = _Py_atomic_load_ptr_relaxed(&values->values[ix]); - *attr = Py_XNewRef(value); + *attr = _Py_XNewRefWithLock(value); success = true; } else { // Caller needs to lookup from the dictionary