https://github.com/python/cpython/commit/c05e71f61ec17a730513dc28f37814b97ad5e053 commit: c05e71f61ec17a730513dc28f37814b97ad5e053 branch: 3.14 author: Miss Islington (bot) <[email protected]> committer: nascheme <[email protected]> date: 2025-11-19T17:00:42-08:00 summary:
[3.14] gh-132657: avoid locks and refcounting in `frozenset` lookups (GH-136107) (gh-141772) gh-132657: avoid locks and refcounting in `frozenset` lookups (GH-136107) (cherry picked from commit f58a7c717584241467970623384ce61cbd776f29) Co-authored-by: Pieter Eendebak <[email protected]> files: A Misc/NEWS.d/next/Core_and_Builtins/2025-07-09-21-27-14.gh-issue-132657.kSA8R3.rst M Objects/setobject.c diff --git a/Misc/NEWS.d/next/Core_and_Builtins/2025-07-09-21-27-14.gh-issue-132657.kSA8R3.rst b/Misc/NEWS.d/next/Core_and_Builtins/2025-07-09-21-27-14.gh-issue-132657.kSA8R3.rst new file mode 100644 index 00000000000000..99f7a990875a0a --- /dev/null +++ b/Misc/NEWS.d/next/Core_and_Builtins/2025-07-09-21-27-14.gh-issue-132657.kSA8R3.rst @@ -0,0 +1 @@ +Improve performance of :class:`frozenset` by removing locks in the free-threading build. diff --git a/Objects/setobject.c b/Objects/setobject.c index 83004e57b66c20..9332c24ac8673b 100644 --- a/Objects/setobject.c +++ b/Objects/setobject.c @@ -86,6 +86,8 @@ set_lookkey(PySetObject *so, PyObject *key, Py_hash_t hash) int probes; int cmp; + int frozenset = PyFrozenSet_CheckExact(so); + while (1) { entry = &so->table[i]; probes = (i + LINEAR_PROBES <= mask) ? LINEAR_PROBES: 0; @@ -102,13 +104,20 @@ set_lookkey(PySetObject *so, PyObject *key, Py_hash_t hash) && unicode_eq(startkey, key)) return entry; table = so->table; - Py_INCREF(startkey); - cmp = PyObject_RichCompareBool(startkey, key, Py_EQ); - Py_DECREF(startkey); - if (cmp < 0) - return NULL; - if (table != so->table || entry->key != startkey) - return set_lookkey(so, key, hash); + if (frozenset) { + cmp = PyObject_RichCompareBool(startkey, key, Py_EQ); + if (cmp < 0) + return NULL; + } else { + // incref startkey because it can be removed from the set by the compare + Py_INCREF(startkey); + cmp = PyObject_RichCompareBool(startkey, key, Py_EQ); + Py_DECREF(startkey); + if (cmp < 0) + return NULL; + if (table != so->table || entry->key != startkey) + return set_lookkey(so, key, hash); + } if (cmp > 0) return entry; mask = so->mask; @@ -2234,10 +2243,16 @@ set_contains_lock_held(PySetObject *so, PyObject *key) int _PySet_Contains(PySetObject *so, PyObject *key) { + assert(so); + int rv; - Py_BEGIN_CRITICAL_SECTION(so); - rv = set_contains_lock_held(so, key); - Py_END_CRITICAL_SECTION(); + if (PyFrozenSet_CheckExact(so)) { + rv = set_contains_lock_held(so, key); + } else { + Py_BEGIN_CRITICAL_SECTION(so); + rv = set_contains_lock_held(so, key); + Py_END_CRITICAL_SECTION(); + } return rv; } _______________________________________________ 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]
