Add ThreadPoolExecutor.submit to ignored methods

[agners]

This is an internal function used during cleanup, and we can't really do anything about it. Even when correctly using the Python library (e.g. acquiring the semaphore with timeout=0), in some rare cases the something to avoid this call.

Fixes: #52

[cbornet]

Thanks for the report and PR.
How about putting the exclusion on ThreadPoolExecutor.submit (and ProcessPoolExecutor.submit ?) instead as it's the usual way to call blocking code in the event loop and it has a smaller scope than _acquire_restore ?

[agners]

How about putting the exclusion on ThreadPoolExecutor.submit (and ProcessPoolExecutor.submit ?) instead as it's the usual way to call blocking code in the event loop and it has a smaller scope than _acquire_restore ?

Hm, I was thinking that _acquire_restore() is smaller scope as it is further down the call chain. But I guess it depends where _acquire_restore() gets called. Since the actual blocking call is in there, wouldn't it be better to have that function specifically excluded?

In any case, my reproducer is not able to reproduce the issue with the exclusions you suggest, so it does work too in practice.

[agners]

I've updated the PR to target ThreadPoolExecutor.submit. I think the ProcessPoolExecutor doesn't need the same treatment.

[cbornet]

Thanks for a lot !