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 f38ab1b2865e99..fcc9d11a9d627e 100644 --- a/Objects/dictobject.c +++ b/Objects/dictobject.c @@ -1488,7 +1488,7 @@ _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; @@ -7015,7 +7015,7 @@ _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; } @@ -7035,7 +7035,7 @@ _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