pythongh-112075: Iterating a dict shouldn't require locks (python#115108

) Makes iteration of a dict be lock free for the forward iteration case.
diegorusso · Apr 17, 2024 · 3b06e72 · 3b06e72
1 parent 9b7fb30
commit 3b06e72
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diff --git a/Include/internal/pycore_dict.h b/Include/internal/pycore_dict.h
@@ -212,6 +212,7 @@ static inline PyDictUnicodeEntry* DK_UNICODE_ENTRIES(PyDictKeysObject *dk) {
 #define DICT_WATCHER_AND_MODIFICATION_MASK ((1 << (DICT_MAX_WATCHERS + DICT_WATCHED_MUTATION_BITS)) - 1)
 
 #define DICT_VALUES_SIZE(values) ((uint8_t *)values)[-1]
+#define DICT_VALUES_USED_SIZE(values) ((uint8_t *)values)[-2]
 
 #ifdef Py_GIL_DISABLED
 #define DICT_NEXT_VERSION(INTERP) \