8345750: Shenandoah: Test TestJcmdHeapDump.java#aggressive intermittent assert(gc_cause() == GCCause::_no_gc) failed: Over-writing cause

[earthling-amzn]

This was not a clean backport, the conflicts were trivial to resolve. This addresses a fairly critical issue where in a mistimed heap dump may cause heap corruption or vm crashes for Shenandoah GC.

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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
• JDK-8345750 needs maintainer approval

Issue

• JDK-8345750: Shenandoah: Test TestJcmdHeapDump.java#aggressive intermittent assert(gc_cause() == GCCause::_no_gc) failed: Over-writing cause (Bug - P3 - Requested)

Reviewers

• Y. Srinivas Ramakrishna (@ysramakrishna - Reviewer)

Reviewing

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[bridgekeeper]

👋 Welcome back wkemper! 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.

[mlbridge]

Webrevs

• 00: Full (8ece8c5c)

[phohensee]

jdk23u-dev?

[earthling-amzn]

/approval request This fixes an issue in which an ill-timed heap dump for Shenandoah could cause a crash or heap corruption. The fault was uncovered by running the TestJcmdHeapDump test repeatedly and the fix has been verified by the same. Shenandoah now follows the pattern established by ZGC for handling heap dump/inspection requests.

[openjdk]

@earthling-amzn
8345750: The approval request has been created successfully.

[ysramakrishna]

🚢

[ysramakrishna]

macos builds seem to be failing because of what appears to be an infra issue.