8324983: race in CompileBroker::possibly_add_compiler_threads

[tkrodriguez]

The number of active compiler threads is decremented before the compiler thread has actually activated so possibly_add_compiler_thread might start a new thread on the existing JavaThread. This adds a check that it's really exiting before proceeding and some new guarantees that ensure threads aren't started on top running threads.

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Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
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• Commit message must refer to an issue

Issue

• JDK-8324983: Race in CompileBroker::possibly_add_compiler_threads (Bug - P3)

Reviewers

• Vladimir Kozlov (@vnkozlov - Reviewer) ⚠️ Review applies to 93145119
• David Holmes (@dholmes-ora - Reviewer)
• Doug Simon (@dougxc - Reviewer)

Reviewing

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Checkout this PR locally:
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$ git checkout pull/17662

Update a local copy of the PR:
$ git checkout pull/17662
$ git pull https://git.openjdk.org/jdk.git pull/17662/head

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Checkout this PR locally:
$ git pr checkout 17662

View PR using the GUI difftool:
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https://git.openjdk.org/jdk/pull/17662.diff

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[bridgekeeper]

👋 Welcome back never! 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]

@tkrodriguez The following label will be automatically applied to this pull request:

• hotspot

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[mlbridge]

Webrevs

• 01: Full - Incremental (7bc1ab8c)
• 00: Full (93145119)

[vnkozlov]

Good.

[openjdk]

@tkrodriguez This change now passes all automated pre-integration checks.

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

After integration, the commit message for the final commit will be:

8324983: race in CompileBroker::possibly_add_compiler_threads

Reviewed-by: kvn, dholmes, dnsimon

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 36 new commits pushed to the master branch:

• 692c9f8: 8325201: (zipfs) Disable TestPosix.setPermissionsShouldConvertToUnix which fails on Windows
• ed06846: 8325037: x86: enable and fix hotspot/jtreg/compiler/vectorization/TestRoundVectFloat.java
• a18b03b: 8324635: (zipfs) Regression in Files.setPosixFilePermissions called on existing MSDOS entries
• 7476e29: 8323680: SA PointerFinder code can do a better job of leveraging existing code to determine if an address is in the TLAB
• 63cb1f8: 8321396: Retire test/jdk/java/util/zip/NoExtensionSignature.java
• f613e13: 8313739: ZipOutputStream.close() should always close the wrapped stream
• adc3604: 8325148: Enable restricted javac warning in java.base
• 1ae8513: 8324858: [vectorapi] Bounds checking issues when accessing memory segments
• 38c0197: 8318105: [jmh] the test java.security.HSS failed with 2 active threads
• 6787c4c: 8325055: Rename Injector.h
• ... and 26 more: https://git.openjdk.org/jdk/compare/1733d2ea244756238c302d802511eb1557cd46ac...master

As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[tkrodriguez]

@dholmes-ora are you planning to approve or should I go ahead and integrate?

[dholmes-ora]

Thanks for the update. Thumbs up on the shared changes.

[tkrodriguez]

Thanks for the reviews.

/integrate

[openjdk]

Going to push as commit 1993652.
Since your change was applied there have been 49 commits pushed to the master branch:

• 55c1446: 8321468: Remove StringUTF16::equals
• 19e9220: 8325169: Reduce String::indexOf overheads
• 89e6a02: 8325064: C2 SuperWord: refactor construct_bb
• d395ac2: 8321373: Build should use LC_ALL=C.UTF-8
• 51671c0: 8323809: Serial: Refactor card table verification
• cdf918b: 8325134: Serial: Remove Generation::used_region
• 4da28b4: 8291809: Convert compiler/c2/cr7200264/TestSSE2IntVect.java to IR verification test
• 0377f1a: 8325133: Missing MEMFLAGS parameter in parts of os API
• df35462: 8323502: javac crash with wrongly typed method block in Flow
• af32262: 8325049: stubGenerator_ppc.cpp should use alignas
• ... and 39 more: https://git.openjdk.org/jdk/compare/1733d2ea244756238c302d802511eb1557cd46ac...master

Your commit was automatically rebased without conflicts.

[openjdk]

@tkrodriguez Pushed as commit 1993652.

💡 You may see a message that your pull request was closed with unmerged commits. This can be safely ignored.

[dougxc]

Thanks @vnkozlov for approving the backport.

/backport jdk22

[openjdk]

@dougxc the backport was successfully created on the branch backport-dougxc-19936526 in my personal fork of openjdk/jdk22. To create a pull request with this backport targeting openjdk/jdk22:master, just click the following link:

➡️ Create pull request

The title of the pull request is automatically filled in correctly and below you find a suggestion for the pull request body:

Hi all,

This pull request contains a backport of commit 19936526 from the openjdk/jdk repository.

The commit being backported was authored by Tom Rodriguez on 5 Feb 2024 and was reviewed by Vladimir Kozlov, David Holmes and Doug Simon.

Thanks!

If you need to update the source branch of the pull then run the following commands in a local clone of your personal fork of openjdk/jdk22:

$ git fetch https://github.com/openjdk-bots/jdk22.git backport-dougxc-19936526:backport-dougxc-19936526
$ git checkout backport-dougxc-19936526
# make changes
$ git add paths/to/changed/files
$ git commit --message 'Describe additional changes made'
$ git push https://github.com/openjdk-bots/jdk22.git backport-dougxc-19936526

⚠️ @dougxc You are not yet a collaborator in my fork openjdk-bots/jdk22. An invite will be sent out and you need to accept it before you can proceed.