8349094: GenShen: Race between control and regulator threads may violate assertions

[earthling-amzn]

Not clean. Several follow up issues here.

---

Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• Change must be properly reviewed (1 review required, with at least 1 Committer)

Issues

• JDK-8349094: GenShen: Race between control and regulator threads may violate assertions (Task - P4)
• JDK-8352428: GenShen: Old-gen cycles are still looping (Bug - P4)
• JDK-8352091: GenShen: assert(!(request.generation->is_old() && _heap->old_generation()->is_doing_mixed_evacuations())) failed: Old heuristic should not request cycles while it waits for mixed evacuation (Task - P4)
• JDK-8351464: Shenandoah: Hang on ShenandoahController::handle_alloc_failure when run test TestAllocHumongousFragment#generational (Bug - P3)
• JDK-8352299: GenShen: Young cycles that interrupt old cycles cannot be cancelled (Bug - P4)

Reviewers

• Kelvin Nilsen (@kdnilsen - Committer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/shenandoah-jdk21u.git pull/174/head:pull/174
$ git checkout pull/174

Update a local copy of the PR:
$ git checkout pull/174
$ git pull https://git.openjdk.org/shenandoah-jdk21u.git pull/174/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 174

View PR using the GUI difftool:
$ git pr show -t 174

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/shenandoah-jdk21u/pull/174.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back wkemper! 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]

@earthling-amzn 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:

8349094: GenShen: Race between control and regulator threads may violate assertions
8352428: GenShen: Old-gen cycles are still looping
8352091: GenShen: assert(!(request.generation->is_old() && _heap->old_generation()->is_doing_mixed_evacuations())) failed: Old heuristic should not request cycles while it waits for mixed evacuation
8351464: Shenandoah: Hang on ShenandoahController::handle_alloc_failure when run test TestAllocHumongousFragment#generational
8352299: GenShen: Young cycles that interrupt old cycles cannot be cancelled

Reviewed-by: kdnilsen

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 3 new commits pushed to the master branch:

• ae5737a: 8350905: Shenandoah: Releasing a WeakHandle's referent may extend its lifetime
• 785f50f: 8351081: Off-by-one error in ShenandoahCardCluster
• 4a65a90: 8351077: Shenandoah: Update comments in ShenandoahConcurrentGC::op_reset_after_collect

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

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

[earthling-amzn]

/issue add 8352428, 8352091, 8351464, 8352299

[openjdk]

@earthling-amzn
Adding additional issue to issue list: 8352428: GenShen: Old-gen cycles are still looping.

Adding additional issue to issue list: 8352091: GenShen: assert(!(request.generation->is_old() && _heap->old_generation()->is_doing_mixed_evacuations())) failed: Old heuristic should not request cycles while it waits for mixed evacuation.

Adding additional issue to issue list: 8351464: Shenandoah: Hang on ShenandoahController::handle_alloc_failure when run test TestAllocHumongousFragment#generational.

Adding additional issue to issue list: 8352299: GenShen: Young cycles that interrupt old cycles cannot be cancelled.

[mlbridge]

Webrevs

• 00: Full (f429cb91)

[earthling-amzn]

Internal testing for this branch is green. MacOS build failure looks unrelated.

/integrate

[openjdk]

Going to push as commit 9a690ba.
Since your change was applied there have been 3 commits pushed to the master branch:

• ae5737a: 8350905: Shenandoah: Releasing a WeakHandle's referent may extend its lifetime
• 785f50f: 8351081: Off-by-one error in ShenandoahCardCluster
• 4a65a90: 8351077: Shenandoah: Update comments in ShenandoahConcurrentGC::op_reset_after_collect

Your commit was automatically rebased without conflicts.

[openjdk]

@earthling-amzn Pushed as commit 9a690ba.

💡 You may see a message that your pull request was closed with unmerged commits. This can be safely ignored.