Fix Select selector backend per-IO waiter queue handling #63
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When multiple fibers wait on different events for the same IO object and only a subset of the polled events happen, some of the fibers could be woken up prematurely (with a subset of the events they asked for) and dropped from the queue. Fix by re-inserting the waiters into the IO object's queue when none of their events were triggered.
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This looks good to me. Thanks for including a test. I'll think about the queue implementation. |
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Thanks for this, I'm going to merge it as it fixes the issue, but I might re-evaluate how the IO wait queue is handled. |
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When multiple fibers wait on different events for the same IO object and only a subset of the polled events happen, some of the fibers could be woken up prematurely (with a subset of the events they asked for) and dropped from the queue.
Fix by re-inserting the waiters into the IO object's queue when none of their events were triggered.
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Contribution
I tried to modify the existing code as little as possible to fix this, but it's really starting to make the per-IO queue handling way more complicated than it should be...