8377179: Improve and document racy use of start/end in ThreadLocalAllocBuffer

[tschatzl]

Hi all,

please review this change that tries to document and streamline the racy use of ThreadLocalAllocBuffer internals.

Testing: gha

Thanks,
Thomas

---

Progress

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Issue

• JDK-8377179: Improve and document racy use of start/end in ThreadLocalAllocBuffer (Enhancement - P4)

Reviewers

• Albert Mingkun Yang (@albertnetymk - Reviewer) Review applies to d229bddb
• Ivan Walulya (@walulyai - Reviewer)

Reviewing

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[bridgekeeper]

👋 Welcome back tschatzl! 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]

@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:

8377179: Improve and document racy use of start/end in ThreadLocalAllocBuffer

Reviewed-by: iwalulya, ayang

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 22 new commits pushed to the master branch:

• bfd5bda: 8374582: [REDO] Move input validation checks to Java for java.lang.StringCoding intrinsics
• 90f3702: 8377226: Inline Thread::set_allocated_bytes
• 5724154: 8376052: Use AttachOperationFailedException rather than AttachNotSupportedException in findTargetProcessTmpDirectory()
• ... and 19 more: https://git.openjdk.org/jdk/compare/d49e29aa8c88a0f966446de4288f32a529f0dd52...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.

[openjdk]

@tschatzl The following label will be automatically applied to this pull request:

• hotspot

When this pull request is ready to be reviewed, an "RFR" email will be sent to the corresponding mailing list. If you would like to change these labels, use the /label pull request command.

[mlbridge]

Webrevs

• 02: Full - Incremental (9b1e6abc)
• 01: Full - Incremental (723233c2)
• 00: Full (d229bddb)

[albertnetymk]

/cc hotspot-gc

Some minor suggestion; up to you.

[openjdk]

@albertnetymk
The hotspot-gc label was successfully added.

[walulyai]

failing tests

[tschatzl]

Thanks @walulyai @albertnetymk for your reviews
/integrate

[openjdk]

Going to push as commit 5f83e9a.
Since your change was applied there have been 24 commits pushed to the master branch:

• 2d6a1aa: 8377313: java/lang/Thread/virtual/stress/GetStackTraceALotWhenPinned.java#id0 timeout
• 1efb298: 8375598: VM crashes with "assert((labs(val) & 0xFFFFFFFF00000000) == 0 || dest == (address)-1) failed: must be 32bit offset or -1" when using too high value for NonNMethodCodeHeapSize
• bfd5bda: 8374582: [REDO] Move input validation checks to Java for java.lang.StringCoding intrinsics
• ... and 21 more: https://git.openjdk.org/jdk/compare/d49e29aa8c88a0f966446de4288f32a529f0dd52...master

Your commit was automatically rebased without conflicts.

[openjdk]

@tschatzl Pushed as commit 5f83e9a.

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