Stream: git-wasmtime

Topic: wasmtime / PR #7144 Fix race condition in `AsyncWriteStream`

Wasmtime GitHub notifications bot (Oct 03 2023 at 19:31):

alexcrichton opened PR #7144 from alexcrichton:fix-flaky-test to bytecodealliance:main:

This commit fixes a synchronization issue with AsyncWriteStream where the writer task would get wedged and not make any further progress. The underlying reason is that notify_waiters was used which did not buffer its notification, meaning that if a waiter wasn't actually waiting then it would miss the notification and block forever on the next call to notified. By using notify_one instead this will buffer up a single notification for the other end for when it gets to waiting for work.

Additionally this removes creation of the Notified future ahead-of-time as that's no longer necessary.

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Wasmtime GitHub notifications bot (Oct 03 2023 at 19:31):

alexcrichton requested elliottt for a review on PR #7144.

Wasmtime GitHub notifications bot (Oct 03 2023 at 19:31):

alexcrichton requested wasmtime-core-reviewers for a review on PR #7144.

Wasmtime GitHub notifications bot (Oct 03 2023 at 19:31):

alexcrichton requested fitzgen for a review on PR #7144.

Wasmtime GitHub notifications bot (Oct 03 2023 at 19:58):

fitzgen submitted PR review.

Wasmtime GitHub notifications bot (Oct 03 2023 at 19:58):

elliottt submitted PR review:

Looks good to me! The difference in behavior between those two similarly named functions is unfortunate, thanks for catching this!

Wasmtime GitHub notifications bot (Oct 03 2023 at 19:59):

alexcrichton updated PR #7144.

Wasmtime GitHub notifications bot (Oct 03 2023 at 19:59):

alexcrichton has enabled auto merge for PR #7144.

Wasmtime GitHub notifications bot (Oct 03 2023 at 21:20):

alexcrichton merged PR #7144.

Last updated: Dec 23 2024 at 12:05 UTC