8381382: Shenandoah: assert(capacity > 0) failed: free regions must have allocation capacity

[pengxiaolong]

Hi all,

This pull request contains a backport of commit 01bfd427 from the openjdk/jdk repository.

The PR fix a memory order related bug that could corrupt heap, therefore I think it is necessary to backport it. It is not a clean backport because of renaming from Atomic to AtomicAccess in hotspot.

Test:

• hotspot_gc_shenandoah

Thanks!

---

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---

Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8381382 needs maintainer approval

Issue

• JDK-8381382: Shenandoah: assert(capacity > 0) failed: free regions must have allocation capacity (Bug - P3 - Requested)

Reviewers

• William Kemper (@earthling-amzn - Committer)
• Kelvin Nilsen (@kdnilsen - no project role)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk25u-dev.git pull/553/head:pull/553
$ git checkout pull/553

Update a local copy of the PR:
$ git checkout pull/553
$ git pull https://git.openjdk.org/jdk25u-dev.git pull/553/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 553

View PR using the GUI difftool:
$ git pr show -t 553

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk25u-dev/pull/553.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back xpeng! 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]

❗ This change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[openjdk]

This backport pull request has now been updated with issue from the original commit.

[mlbridge]

Webrevs

• 00: Full (6fdeb9f0)

[earthling-amzn]

Thank you!

[kdnilsen]

Thanks

[earthling-amzn]

/approval request This change addresses a correctness issue introduced in https://bugs.openjdk.org/browse/JDK-8345423. Only Shenandoah is affected by the change.

[openjdk]

@earthling-amzn Only the author (@pengxiaolong) is allowed to issue the /approval command.

[pengxiaolong]

/approval request This change addresses a correctness issue introduced in https://bugs.openjdk.org/browse/JDK-8345423. Only Shenandoah is affected by the change.

[openjdk]

@pengxiaolong
8381382: The approval request has been created successfully.