8272985: Reference discovery is confused about atomicity and degree of parallelism

[tschatzl]

Hi all,

can I have reviews for this change that fixes some (apparent) confusion between atomicity (of the discovery in the ReferenceProcessor sense) vs. the currently selected degree of parallelism?

For all four different combinations of atomicity and parallelism the discovered link in the java.lang.ref.Reference needs to be updated differently using a different kind of access, instead of just two based on atomicity.

I'll fix the use of atomic in ReferenceProcessor in a separate CR to hopefully remove the confusion for the reader too.

Testing: tier1-5, internal perf benchmarks without regressions

Thanks,
Thomas

---

Progress

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Issue

• JDK-8272985: Reference discovery is confused about atomicity and degree of parallelism

Reviewers

• Albert Mingkun Yang (@albertnetymk - Reviewer)
• Kim Barrett (@kimbarrett - Reviewer)

Reviewing

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[mlbridge]

Webrevs

• 01: Full - Incremental (e213e69c)
• 00: Full (115be125)

[openjdk]

@tschatzl 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:

8272985: Reference discovery is confused about atomicity and degree of parallelism

Reviewed-by: ayang, kbarrett

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 65 new commits pushed to the master branch:

• d414a88: 8273240: Dynamic test ArchiveConsistency.java should use CDSArchiveUtils
• 23fa0dc: 8272905: Consolidate discovered lists processing
• ff4018b: 8268148: unchecked warnings handle ? and ? extends Object differently
• 8c37909: 8273234: extended 'for' with expression of type tvar causes the compiler to crash
• 28ba78e: 8244675: assert(IncrementalInline || (_late_inlines.length() == 0 && !has_mh_late_inlines()))
• d05494f: 8266239: Some duplicated javac command-line options have repeated effect
• 93eec9a: 8272776: NullPointerException not reported
• 7b023a3: 8273257: jshell doesn't compile a sealed hierarchy with a sealed interface and a non-sealed leaf
• f17ee0c: 8273263: Incorrect recovery attribution of record component type when j.l.Record is unavailable
• fa9c865: 8273112: -Xloggc: should override -verbose:gc
• ... and 55 more: https://git.openjdk.java.net/jdk/compare/f55d5ab5177b6e08e8499abc181a320a98b28a5f...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.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[kimbarrett]

Looks good.

[tschatzl]

Thanks @kimbarrett @albertnetymk for your reviews.

/integrate

[openjdk]

Going to push as commit fb5b144.
Since your change was applied there have been 71 commits pushed to the master branch:

• 70ed6c5: 8272878: JEP 381 cleanup: Remove unused Solaris code in sun.font.TrueTypeGlyphMapper
• b4e5b28: 8273221: Guard GCIdMark against nested calls
• 4d25e6f: 8273335: compiler/blackhole tests should not run with interpreter-only VMs
• c640fe4: 7188098: TEST_BUG: closed/javax/sound/midi/Synthesizer/Receiver/bug6186488.java fails
• cec6c06: 8272232: javax/swing/JTable/4275046/bug4275046.java failed with "Expected value in the cell: 'rededited' but found 'redEDITED'."
• 14a3ac0: 8271911: replay compilations of methods which use JSR292 (easy cases)
• d414a88: 8273240: Dynamic test ArchiveConsistency.java should use CDSArchiveUtils
• 23fa0dc: 8272905: Consolidate discovered lists processing
• ff4018b: 8268148: unchecked warnings handle ? and ? extends Object differently
• 8c37909: 8273234: extended 'for' with expression of type tvar causes the compiler to crash
• ... and 61 more: https://git.openjdk.java.net/jdk/compare/f55d5ab5177b6e08e8499abc181a320a98b28a5f...master

Your commit was automatically rebased without conflicts.

[openjdk]

@tschatzl Pushed as commit fb5b144.

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