8253778: ShenandoahSafepoint::is_at_shenandoah_safepoint should not access VMThread state from other threads

[shipilev]

There are lots of Shenandoah-related test failures in current runs, triggered by new assert in JDK-8212107. The assert looks legitimate, and Shenandoah code should instead be more relaxed here, by checking it runs in VMThread before accessing its state.

Testing:

• hotspot_gc_shenandoah

---

Progress

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Issue

• JDK-8253778: ShenandoahSafepoint::is_at_shenandoah_safepoint should not access VMThread state from other threads

Reviewers

• Jie Fu (@DamonFool - Committer)
• Robbin Ehn (@robehn - Reviewer)
• Roman Kennke (@rkennke - Reviewer)

Download

$ git fetch https://git.openjdk.java.net/jdk pull/424/head:pull/424
$ git checkout pull/424

[bridgekeeper]

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[openjdk]

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

• hotspot-gc
• shenandoah

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[mlbridge]

Webrevs

• 01: Full - Incremental (fe40601)
• 00: Full (054c584)

[DamonFool]

Looks good to me.

Thanks for fixing it.

[robehn]

Not sure what it's worth, but seems reasonable to me.

[openjdk]

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

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

8253778: ShenandoahSafepoint::is_at_shenandoah_safepoint should not access VMThread state from other threads

Reviewed-by: jiefu, rehn, rkennke

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At the time when this comment was updated there had been 2 new commits pushed to the master branch:

• 4c65365: 8253792: javax.swing.text.GapContent documentation typos
• 3078b5f: 6441211: Small Error in API at javax.swing.plaf.synth.Region

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[shipilev]

/integrate

[openjdk]

@shipilev Since your change was applied there have been 2 commits pushed to the master branch:

• 4c65365: 8253792: javax.swing.text.GapContent documentation typos
• 3078b5f: 6441211: Small Error in API at javax.swing.plaf.synth.Region

Your commit was automatically rebased without conflicts.

Pushed as commit 8331e63.

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