8386085: Livelock in AbstractQueuedSynchronizer.cleanQueue() when multiple threads do tryAcquire() with a short timeout and no permits available

[kirill-shirokov]

Testing done:

• juc-tests-26-windows-x64.log
• 8386085-BugReproducer2-26-linux-x64.log
• juc-tests-26-linux-x64.log
• juc-tests-26-macosx-aarch64.log

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Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8386085 needs maintainer approval

Issue

• JDK-8386085: Livelock in AbstractQueuedSynchronizer.cleanQueue() when multiple threads do tryAcquire() with a short timeout and no permits available (Bug - P3 - Requested)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk26u.git pull/214/head:pull/214
$ git checkout pull/214

Update a local copy of the PR:
$ git checkout pull/214
$ git pull https://git.openjdk.org/jdk26u.git pull/214/head

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Checkout this PR locally:
$ git pr checkout 214

View PR using the GUI difftool:
$ git pr show -t 214

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Download this PR as a diff file:
https://git.openjdk.org/jdk26u/pull/214.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back kshiroko! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

❗ This change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[openjdk]

This backport pull request has now been updated with issue from the original commit.

[openjdk]

⚠️ @kirill-shirokov This change is now ready for you to apply for maintainer approval. This can be done directly in each associated issue or by using the /approval command.

[mlbridge]

Webrevs

• 00: Full (1f3801b4)

[kirill-shirokov]

All windows failures are due to environment, not related to the JDK (it could not install VS)

[kirill-shirokov]

/approval request This PR fixes a long-standing bug in java.util.concurrent which leads to a livelock in all participating threads with 100% CPU consumption. Tested with reproducer and j.u.c. test on major platforms and CPUs.

[openjdk]

@kirill-shirokov
8386085: The approval request has been created successfully.

[bridgekeeper]

@kirill-shirokov This pull request has been inactive for more than 4 weeks and will be automatically closed if another 4 weeks passes without any activity. To avoid this, simply issue a /touch or /keepalive command to the pull request. Feel free to ask for assistance if you need help with progressing this pull request towards integration!

[bridgekeeper]

@kirill-shirokov This pull request has been inactive for more than 8 weeks and will now be automatically closed. If you would like to continue working on this pull request in the future, feel free to reopen it! This can be done using the /open pull request command.

[kirill-shirokov]

/open

[openjdk]

@kirill-shirokov This pull request is now open

[kirill-shirokov]

/approval request The fix has been integrated into tip and jdk27 (openjdk/jdk#31595), can we proceed with integrating to the lower versions (17, 21, 25, 26)?

[openjdk]

@kirill-shirokov
8386085: The approval request has been updated successfully.