gh-117657: Quiet TSAN warnings about remaining non-atomic accesses of tstate->state - #118165
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DinoV merged 1 commit intoApr 23, 2024
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gh-117657: Quiet TSAN warnings about remaining non-atomic accesses of tstate->state#118165DinoV merged 1 commit into
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…tate` These should be the last instances of TSAN warning of data races when accessing `tstate->state` non-atomically. TSAN reports a race between accessing `tstate->state` in `_PyThreadState_Suspend()` and the compare/exhange in `park_detached_threads`. This is a false positive due to TSAN modeling failed compare/exchange operations as writes. TSAN reports a race between accessing `tstate->state` in `_PySemaphore_Wait()` and the compare/exchange in `park_detached_threads`. This is the same issue that we saw in pythongh-117830.
mpage
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April 23, 2024 17:02
DinoV
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LGTM!
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These should be the last instances of TSAN warning of data races when accessing tstate->state non-atomically.
TSAN reports a race (example) between accessing tstate->state in _PyThreadState_Suspend():
cpython/Python/pystate.c
Line 2099 in fc21c7f
and the compare/exchange in park_detached_threads():
cpython/Python/pystate.c
Lines 2172 to 2173 in fc21c7f
This is a false positive due to TSAN modeling failed compare/exchange operations as writes.
TSAN also reports a race (example) between accessing tstate->state in _PySemaphore_Wait():
cpython/Python/parking_lot.c
Line 197 in fc21c7f
and the compare/exchange in park_detached_threads() above. This is the same issue that we saw in gh-117830.