gh-130373: Avoid locking in _LOAD_ATTR_WITH_HINT#130372
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| #ifdef Py_GIL_DISABLED | ||
| _PyDict_EnsureSharedOnRead(dict_o); | ||
| #endif |
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I think we should de-opt here if the condition doesn't hold. The critical section is escaping so previously validated guards might not hold.
Something like:
EXIT_IF(!_Py_IsOwnedByCurrentThread((PyObject *)dict_o) && !IS_DICT_SHARED(dict_o));
EDIT: EXIT_IF instead of DEOPT_IF
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I think we need to do DEOPT_IF because apparently we can't mix and match them. I've updated it to do the ownership check and then mark the dictionary as shared when doing the specialization.
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@DinoV - this lgtm modulo Sam's comment. Can you take a look? |
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LGTM. The tail calling check failure should go away if you merge main. Not sure about the other failing check. |
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Adds a lock-free lookup of the hinted location
https://github.com/facebookexperimental/free-threading-benchmarking/tree/main/results/bm-20250219-3.14.0a5+-6a1fe7e-NOGIL