Fix a panic due to a race in unpark and park #5871
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Use `std::thread::scope` to keep everything local to just the tests.
This commit fixes a panic in the `ParkingSpot` implementation where an `unpark` signal may not get acknowledged when a waiter times out, causing the waiter to remove itself from the internal map but panic thinking that it missed an unpark signal. The fix in this commit is to consume unpark signals when a timeout happens. This can lead to another possible race I've detailed in the comments which I believe is allowed by the specification of park/unpark in wasm.
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This was uncovered by this failing test run |
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We also didn't find this earlier since nothing in the test suite presumably exercises wait-with-timeout until #5858 was merged. |
Co-authored-by: Andrew Brown <[email protected]>
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This commit fixes a panic in the
ParkingSpotimplementation where anunparksignal may not get acknowledged when a waiter times out,causing the waiter to remove itself from the internal map but panic
thinking that it missed an unpark signal.
The fix in this commit is to consume unpark signals when a timeout
happens. This can lead to another possible race I've detailed in the
comments which I believe is allowed by the specification of park/unpark
in wasm.