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

[kirill-shirokov]

Testing done:

• 8386085-BugReproducer2-25-linux-x64.log
• juc-tests-25-linux-x64.log
• juc-tests-25-macosx-aarch64.log
• juc-tests-25-windows-x64.log

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Progress

• Change must not contain extraneous whitespace
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• JDK-8386085 needs maintainer approval

Issue

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

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[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 (7079c7a2)

[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.

[GoeLin]

Hi @kirill-shirokov
please backport to jdk27 first. Best to jdk27, not jdk27u to get more coverage. I defer the other backports for now.

[kirill-shirokov]

Hi @GoeLin, here's backports for jdk27, jdk26u:
openjdk/jdk#31595
openjdk/jdk26u#214

And I created a backport for jdk27u just in case (I can delete either one):
openjdk/jdk27u#6