8361706: Parallel weak klass link cleaning does not clean out previous klasses

[tschatzl]

Hi all,

please review this fix to parallel weak klass link cleaning.

KlassCleaningTask::work() misses cleaning out previous versions of klasses (created by JVMTI class redefinition) as the regular single-threaded variant would do when calling Klass::clean_weak_klass_links() with clean_live_klasses = true.

The fix moves the cleaning of weak klass links for previous versions of the klass into InstanceKlass::clean_weak_instanceklass_links().

Testing: gha, tier1-5, many runs of vmTestbase/nsk/jvmti/RedefineClasses/StressRedefine/TestDescription.java(with JDK-8361952 also out for review)

Thanks,
Thomas

---

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Issue

• JDK-8361706: Parallel weak klass link cleaning does not clean out previous klasses (Bug - P2)

Reviewers

• Erik Österlund (@fisk - Reviewer)
• Coleen Phillimore (@coleenp - Reviewer)

Reviewing

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[tschatzl]

/label add hotspot-gc
/label add hotspot-runtime

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👋 Welcome back tschatzl! 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]

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

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

8361706: Parallel weak klass link cleaning does not clean out previous klasses

Reviewed-by: eosterlund, coleenp

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At the time when this comment was updated there had been 13 new commits pushed to the master branch:

• a86dd56: 8360936: Test compiler/onSpinWait/TestOnSpinWaitAArch64.java fails after JDK-8359435
• 76442f3: 8361494: [IR Framework] Escape too much in replacement of placeholder
• 445e5ec: 8361342: Shenandoah: Evacuation may assert on invalid mirror object after JDK-8340297
• ... and 10 more: https://git.openjdk.org/jdk/compare/3d37c4e37ac6e3fb7915de46ed98136453b8840a...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.

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[openjdk]

@tschatzl
The hotspot-gc label was successfully added.

[openjdk]

@tschatzl
The hotspot-runtime label was successfully added.

[mlbridge]

Webrevs

• 00: Full (f3dcf761)

[coleenp]

Can you make InstanceKlass::clean_weak_instanceklass_links() protected? If not, this looks good.

[tschatzl]

Can you make InstanceKlass::clean_weak_instanceklass_links() protected? If not, this looks good.

It is required to be public right now.

Thanks @coleenp @fisk for your reviews

/integrate

[openjdk]

Going to push as commit 99c299f.
Since your change was applied there have been 29 commits pushed to the master branch:

• 272e66d: 8361952: Installation of MethodData::extra_data_lock() misses synchronization on reader side
• 14c79be: 8361140: Missing OptimizePtrCompare check in ConnectionGraph::reduce_phi_on_cmp
• 7c34bdf: 8362122: Problem list TestStressBailout until JDK-8361752 is fixed
• ... and 26 more: https://git.openjdk.org/jdk/compare/3d37c4e37ac6e3fb7915de46ed98136453b8840a...master

Your commit was automatically rebased without conflicts.

[openjdk]

@tschatzl Pushed as commit 99c299f.

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