FIX: Fix RwLock not treating multiple readers correctly in release mode #170
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bkragl
approved these changes
Mar 6, 2025
| @@ -222,7 +222,7 @@ impl<T: ?Sized> RwLock<T> { | |||
| state.holder = RwLockHolder::Read(readers); | |||
| } | |||
| (RwLockType::Read, RwLockHolder::Read(readers)) => { | |||
| debug_assert!(readers.insert(me)); | |||
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ouch. we need to make sure there's no effectful code inside any debug assertion.
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Yeah, forgot to mention, but I checked that there are no other debug_asserts with effectful code.
sarsko
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Mar 6, 2025
…de (#170) * FIX: Fix RwLock not treating multiple readers correctly in release mode * Clippy * Run tests in release when running workflow * Reduce dropped_acquire_must_release_random test case count to 1000 (from 10_000)
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Turns out
RwLockdoesn't function correctly when run in release mode, as we don't insert to the readers when there already is a reader. This PR fixes that.Surprised this hasn't been an issue previously, I guess
RwLockjust isn't used much.Discovered this when I tried to update the workflow to run the tests in release mode, where some of the
RwLocktests failed.This (and similar issues) might explain the instances where we have seen non-replayable schedules generated in release mode and replayed in debug mode, or vice versa.
I should do a pass and check if all tests replay with schedules created in the opposite mode.
By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.