8263832: Shenandoah: Fixing parallel thread iteration in final mark task

[zhengyu123]

Please review this trivial patch that parallelizes thread iteration in ShenandoahFinalMarkingTask

Test:

• hotspot_gc_shenandoah

---

Progress

• Change must not contain extraneous whitespace
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Issue

• JDK-8263832: Shenandoah: Fixing parallel thread iteration in final mark task

Reviewers

• Roman Kennke (@rkennke - Reviewer)

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To checkout this PR locally:
$ git fetch https://git.openjdk.java.net/jdk pull/3080/head:pull/3080
$ git checkout pull/3080

To update a local copy of the PR:
$ git checkout pull/3080
$ git pull https://git.openjdk.java.net/jdk pull/3080/head

[bridgekeeper]

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[openjdk]

@zhengyu123 The following labels will be automatically applied to this pull request:

• hotspot-gc
• shenandoah

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[mlbridge]

Webrevs

• 00: Full (965a72c)

[rkennke]

It's not trivial. Maybe I'm missing something, but where are the threads claimed now? I believe you should leave the claiming code where it is, right? And only change threads_do() to possibly_parallel_threads_do().

[zhengyu123]

It's not trivial. Maybe I'm missing something, but where are the threads claimed now? I believe you should leave the claiming code where it is, right? And only change threads_do() to possibly_parallel_threads_do().

Threads are claimed inside Threads::possibly_parallel_threads_do() (https://github.com/openjdk/jdk/blob/master/src/hotspot/share/runtime/thread.cpp#L2866)

[rkennke]

Ah

It's not trivial. Maybe I'm missing something, but where are the threads claimed now? I believe you should leave the claiming code where it is, right? And only change threads_do() to possibly_parallel_threads_do().

Threads are claimed inside Threads::possibly_parallel_threads_do() (https://github.com/openjdk/jdk/blob/master/src/hotspot/share/runtime/thread.cpp#L2866)

Ah ok, alright. It's clearly too late for work! Sorry for the noise.

[rkennke]

Ok, thanks!

[openjdk]

@zhengyu123 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:

8263832: Shenandoah: Fixing parallel thread iteration in final mark task

Reviewed-by: rkennke

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 7 new commits pushed to the master branch:

• c82a673: 8262001: java/lang/management/ThreadMXBean/ResetPeakThreadCount.java failed with "RuntimeException: Current Peak = 14 Expected to be == previous peak = 7 + 8"
• 01ddf3d: 8263622: The java.awt.color.ICC_Profile#setData invert the order of bytes for the "head" tag
• e34f766: 8252723: Run stack016.java also with C2-only
• 2173fed: 8263439: getSupportedAttributeValues() throws NPE for Finishings attribute
• e543a50: 8261352: Create implementation for component peer for all the components who should be ignored in a11y interactions
• 21db0f6: 8263659: Reflow GTestResultParser for better readability
• e333b6e: 8246494: introduce vm.flagless at-requires property

Please see this link for an up-to-date comparison between the source branch of this pull request and the master branch.
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.

[zhengyu123]

/integrate

[openjdk]

@zhengyu123 Since your change was applied there have been 12 commits pushed to the master branch:

• 434a399: 8260274: Cipher.init(int, key) does not use highest priority provider for random bytes
• 6aa28b3: 8263827: Suspend "missing" javadoc doclint checks for smartcardio
• ed1e25d: 8263833: Stop disabling warnings for sunFont.c with gcc
• 788e30c: 8263320: [test] Add Object Stream Formatter to work with test utility HexPrinter
• fa0f161: 8263742: (bf) MappedByteBuffer.force() should use the capacity as its upper bound
• c82a673: 8262001: java/lang/management/ThreadMXBean/ResetPeakThreadCount.java failed with "RuntimeException: Current Peak = 14 Expected to be == previous peak = 7 + 8"
• 01ddf3d: 8263622: The java.awt.color.ICC_Profile#setData invert the order of bytes for the "head" tag
• e34f766: 8252723: Run stack016.java also with C2-only
• 2173fed: 8263439: getSupportedAttributeValues() throws NPE for Finishings attribute
• e543a50: 8261352: Create implementation for component peer for all the components who should be ignored in a11y interactions
• ... and 2 more: https://git.openjdk.java.net/jdk/compare/8c8d1b31f0cb8a1af3a5f6e9a8c7e4c9268f4bfb...master

Your commit was automatically rebased without conflicts.

Pushed as commit d185655.

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