8257817: Shenandoah: Don't race with conc-weak-in-progress flag in weak-LRB

[zhengyu123]

After concurrent weak root processing, it should perform handshake first to ensure there are no dirty loads (loads have yet processed by barriers) in Java thread, before it resets conc-weak-root-in-progress flag.

• hotspot_gc_shenandoah

---

Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• Change must be properly reviewed

Issue

• JDK-8257817: Shenandoah: Don't race with conc-weak-in-progress flag in weak-LRB

Reviewers

• Roman Kennke (@rkennke - Reviewer)

Download

$ git fetch https://git.openjdk.java.net/jdk pull/1673/head:pull/1673
$ git checkout pull/1673

[bridgekeeper]

👋 Welcome back zgu! 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]

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

• hotspot-gc
• shenandoah

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[mlbridge]

Webrevs

• 00: Full (058bb16)

[rkennke]

Looks good to me!
Might want to see in a follow-up if binding conc-roots-flag to should_do_class_unloading() is sane.

[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:

8257817: Shenandoah: Don't race with conc-weak-in-progress flag in weak-LRB

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:

• a265c20: 8255619: Localized WinResources.properties have MsiInstallerStrings_en.wxl resource
• e3793e5: 8257514: Fix the issues in jdk.jpackage identified by SpotBugs
• bbc44f5: 8257186: Size of heap segments is not computed correctlyFix overflow in size computation for heap segments
• b4b9828: 8254784: javac should reject records with @SafeVarargs applied to varargs record component
• dcf63f8: 8257788: Class fields could be local in the SunJSSE provider
• d29c78d: 8257679: Improved unix compatibility layer in Windows build (winenv)
• 74be819: 8257517: LogCompilation: Add -z to the help messages

Please see this link for an up-to-date comparison between the source branch of this pull request and the master branch.
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[zhengyu123]

Looks good to me!
Might want to see in a follow-up if binding conc-roots-flag to should_do_class_unloading() is sane.

Thanks for reviewing. There is already a RFE (JDK-8255837) to clean can/should_do_xxx up, as part of ongoing refactoring.

[zhengyu123]

/integrate

[openjdk]

@zhengyu123 Since your change was applied there have been 7 commits pushed to the master branch:

• a265c20: 8255619: Localized WinResources.properties have MsiInstallerStrings_en.wxl resource
• e3793e5: 8257514: Fix the issues in jdk.jpackage identified by SpotBugs
• bbc44f5: 8257186: Size of heap segments is not computed correctlyFix overflow in size computation for heap segments
• b4b9828: 8254784: javac should reject records with @SafeVarargs applied to varargs record component
• dcf63f8: 8257788: Class fields could be local in the SunJSSE provider
• d29c78d: 8257679: Improved unix compatibility layer in Windows build (winenv)
• 74be819: 8257517: LogCompilation: Add -z to the help messages

Your commit was automatically rebased without conflicts.

Pushed as commit 395b6bd.

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