8275035: Clean up worker thread infrastructure

[pliden]

I propose that we clean up our GangWorker/WorkGang and related classes, to remove abstractions we no longer need (after CMS was removed, MutexDispatcher was removed, Parallel is now using WorkGang, etc) and adjusting names as follows:

• Rename AbstractGangTask to WorkerTask
• Rename WorkGang to WorkerThreads
• Fold GangWorker into WorkerThread
• Fold WorkManager into WorkerThreads
• Move SubTaskDone and friends to a new workerUtils.hpp/cpp

I've split things up into several commits to make it easier to review.

Testing: Passes Tier 1-3 on all Oracle platforms.

---

Progress

• Change must not contain extraneous whitespace
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• Change must be properly reviewed

Issue

• JDK-8275035: Clean up worker thread infrastructure

Reviewers

• Stefan Karlsson (@stefank - Reviewer) ⚠️ Review applies to 39b23f4
• Albert Mingkun Yang (@albertnetymk - Reviewer) ⚠️ Review applies to 39b23f4

Reviewing

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[bridgekeeper]

👋 Welcome back pliden! 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]

@pliden The following labels will be automatically applied to this pull request:

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• serviceability
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[mlbridge]

Webrevs

• 01: Full (9a89f785)
• 00: Full (39b23f42)

[stefank]

Looks good

[openjdk]

@pliden 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:

8275035: Clean up worker thread infrastructure

Reviewed-by: stefank, ayang

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At the time when this comment was updated there had been no new commits pushed to the master branch. If another commit should be pushed before you perform the /integrate command, your PR will be automatically rebased. If you prefer to avoid any potential automatic rebasing, please check the documentation for the /integrate command for further details.

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[dholmes-ora]

Changes to non GC files look fine.

Thanks,
David

[openjdk]

@pliden this pull request can not be integrated into master due to one or more merge conflicts. To resolve these merge conflicts and update this pull request you can run the following commands in the local repository for your personal fork:

git checkout 8275035_clean_up_worker_threads
git fetch https://git.openjdk.java.net/jdk master
git merge FETCH_HEAD
# resolve conflicts and follow the instructions given by git merge
git commit -m "Merge master"
git push

[pliden]

Thanks all for reviewing!

/integrate

[openjdk]

Going to push as commit 54b8870.
Since your change was applied there have been 3 commits pushed to the master branch:

• 3b0b6ad: 8275226: Shenandoah: Relax memory constraint for worker claiming tasks/ranges
• 8d9004b: 8274781: Use monospace font for enclosing interface
• 333c469: 8275262: [BACKOUT] AArch64: Implement string_compare intrinsic in SVE

Your commit was automatically rebased without conflicts.

[openjdk]

@pliden Pushed as commit 54b8870.

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