8275730: Relax memory constraint on MultiThreadedRefCounter

[zhengyu123]

It is just an atomic counter, only needs atomic guarantee.

---

Progress

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

Issue

• JDK-8275730: Relax memory constraint on MultiThreadedRefCounter

Reviewers

• Markus Grönlund (@mgronlun - Reviewer)
• Yumin Qi (@yminqi - Reviewer)

Reviewing

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Checkout this PR locally:
$ git fetch https://git.openjdk.java.net/jdk pull/6069/head:pull/6069
$ git checkout pull/6069

Update a local copy of the PR:
$ git checkout pull/6069
$ git pull https://git.openjdk.java.net/jdk pull/6069/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 6069

View PR using the GUI difftool:
$ git pr show -t 6069

Using diff file

Download this PR as a diff file:
https://git.openjdk.java.net/jdk/pull/6069.diff

[bridgekeeper]

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[openjdk]

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[mlbridge]

Webrevs

• 00: Full (82b10c23)

[mgronlun]

Looks good.

[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:

8275730: Relax memory constraint on MultiThreadedRefCounter

Reviewed-by: mgronlun, minqi

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 133 new commits pushed to the master branch:

• 2b02b6f: 8274942: AssertionError at jdk.compiler/com.sun.tools.javac.util.Assert.error(Assert.java:155)
• bb92fb0: 8274930: sun/tools/jps/TestJps.java can fail with long VM arguments string
• 6a04899: 8275840: Add test to java/nio/channels/Channels/TransferTo.java to test transfer sizes > 2GB
• 01105d6: 8276367: ProblemList vmTestbase/nsk/jvmti/RedefineClasses/StressRedefineWithoutBytecodeCorruption/TestDescription.java
• 8fc16f1: 8275729: Qualified method names in CodeHeap Analytics
• fa4ce82: 8276260: (se) Remove java/nio/channels/Selector/Wakeup.java from ProblemList (win)
• 495c828: 8276188: Clarify "default charset" descriptions in String class
• cd778f5: 8202667: java/awt/Debug/DumpOnKey/DumpOnKey.java times out on Windows
• b889f2a: 8276175: codestrings.validate_vm gtest still broken on ppc64 after JDK-8276046
• 5b4e398: 8275766: (tz) Update Timezone Data to 2021e
• ... and 123 more: https://git.openjdk.java.net/jdk/compare/af14650127de47058b958be411503584c0ba6323...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.

[zhengyu123]

Thanks for the review, @mgronlun

[yminqi]

add (sub) itself also with a parameter of atomic_memory_order, but this change is more concise.
LGTM.

[zhengyu123]

Thanks, @yminqi

[zhengyu123]

/integrate

[openjdk]

Going to push as commit a316c06.
Since your change was applied there have been 137 commits pushed to the master branch:

• 6150633: 8276348: Use blessed modifier order in java.base
• 465d350: 8276157: C2: Compiler stack overflow during escape analysis on Linux x86_32
• 7439b59: 8276044: ciReplay: C1 does not dump a replay file when using DumpReplay as compile command option
• 87b926e: 8275086: compiler/c2/irTests/TestPostParseCallDevirtualization.java fails when compiler1 is disabled
• 2b02b6f: 8274942: AssertionError at jdk.compiler/com.sun.tools.javac.util.Assert.error(Assert.java:155)
• bb92fb0: 8274930: sun/tools/jps/TestJps.java can fail with long VM arguments string
• 6a04899: 8275840: Add test to java/nio/channels/Channels/TransferTo.java to test transfer sizes > 2GB
• 01105d6: 8276367: ProblemList vmTestbase/nsk/jvmti/RedefineClasses/StressRedefineWithoutBytecodeCorruption/TestDescription.java
• 8fc16f1: 8275729: Qualified method names in CodeHeap Analytics
• fa4ce82: 8276260: (se) Remove java/nio/channels/Selector/Wakeup.java from ProblemList (win)
• ... and 127 more: https://git.openjdk.java.net/jdk/compare/af14650127de47058b958be411503584c0ba6323...master

Your commit was automatically rebased without conflicts.

[openjdk]

@zhengyu123 Pushed as commit a316c06.

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