gh-155477: Fix multiprocessing.Pool deadlock on close() with a buffersize imap - #155478
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gh-155477: Fix multiprocessing.Pool deadlock on close() with a buffersize imap#155478tonghuaroot wants to merge 1 commit into
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…buffersize imap close() did not release the buffersize semaphores that throttle the task generator, so a partially-consumed imap left the task handler blocked and join() deadlocked. Release them in close() and stop the generator once the pool leaves the RUN state.
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The buffersize variant of
Pool.imap()/imap_unordered()throttles the taskgenerator on a semaphore.
close()did not release those semaphores (onlyterminate()did), so a partially-consumed iterator left the task handlerblocked in
sema.acquire()andjoin()deadlocked. Release the buffersizesemaphores in
close(), and stop the task generator once the pool leaves theRUN state. Introduced in gh-64192.