Feature or enhancement

The refleak checking relies on per-interpreter "total" refcount tracking. It uses non-atomic operations and is not thread-safe without the GIL.

In the free-threaded build, I think we should primarily track counts in PyThreadState and occasionally aggregate the results into the per-interpreter total refcount using atomic operations.

See:

There is also the legacy _Py_RefTotal, but that's just preserved for ABI compatibility. I don't think we have to do anything with that.

Linked PRs

• gh-117439: Make refleak checking thread-safe without the GIL #117469