8253797: [cgroups v2] Account for the fact that swap accounting is disabled on some systems

[jmtd]

This is a clean backport of 8253797 (via 11u) for jdk8u-dev for cgroups v2 support.

The changed files are exercised by the jtreg test TestSystemMetrics.java which passes on my cgroups v2 system.

---

Progress

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

Issue

• JDK-8253797: [cgroups v2] Account for the fact that swap accounting is disabled on some systems

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk8u-dev pull/185/head:pull/185
$ git checkout pull/185

Update a local copy of the PR:
$ git checkout pull/185
$ git pull https://git.openjdk.org/jdk8u-dev pull/185/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 185

View PR using the GUI difftool:
$ git pr show -t 185

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk8u-dev/pull/185.diff

[bridgekeeper]

👋 Welcome back jdowland! A progress list of the required criteria for merging this PR into pr/168 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 backport pull request has now been updated with issue from the original commit.

[jmtd]

/clean

[openjdk]

@jmtd This backport pull request is now marked as clean

[mlbridge]

Webrevs

• 04: Full (31d06168)
• 03: Full (7c0dab20)
• 02: Full (5e1206fb)
• 01: Full - Incremental (48414a2a)
• 00: Full (48414a2a)

[openjdk-notifier]

The parent pull request that this pull request depends on has now been integrated and the target branch of this pull request has been updated. This means that changes from the dependent pull request can start to show up as belonging to this pull request, which may be confusing for reviewers. To remedy this situation, simply merge the latest changes from the new target branch into this pull request by running commands similar to these in the local repository for your personal fork:

git checkout 8253797-jdk8u-dev
git fetch https://git.openjdk.org/jdk8u-dev master
git merge FETCH_HEAD
# if there are conflicts, follow the instructions given by git merge
git commit -m "Merge master"
git push

[openjdk]

@jmtd this pull request can not be integrated into master due to one or more merge conflicts. To resolve these merge conflicts and update this pull request you can run the following commands in the local repository for your personal fork:

git checkout 8253797-jdk8u-dev
git fetch https://git.openjdk.org/jdk8u-dev master
git merge FETCH_HEAD
# resolve conflicts and follow the instructions given by git merge
git commit -m "Merge master"
git push

[openjdk]

@jmtd Please do not rebase or force-push to an active PR as it invalidates existing review comments. All changes will be squashed into a single commit automatically when integrating. See OpenJDK Developers’ Guide for more information.

[openjdk]

@jmtd This change now passes all automated pre-integration checks.

After integration, the commit message for the final commit will be:

8253797: [cgroups v2] Account for the fact that swap accounting is disabled on some systems

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 no new commits pushed to the master branch. If another commit should be pushed before you perform the /integrate command, your PR will be automatically rebased. If you prefer to avoid any potential 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]

@jmtd Please do not rebase or force-push to an active PR as it invalidates existing review comments. All changes will be squashed into a single commit automatically when integrating. See OpenJDK Developers’ Guide for more information.

[openjdk]

@jmtd Please do not rebase or force-push to an active PR as it invalidates existing review comments. Note for future reference, the bots always squash all changes into a single commit automatically as part of the integration. See OpenJDK Developers’ Guide for more information.

[openjdk-notifier]

The parent pull request that this pull request depends on has now been integrated and the target branch of this pull request has been updated. This means that changes from the dependent pull request can start to show up as belonging to this pull request, which may be confusing for reviewers. To remedy this situation, simply merge the latest changes from the new target branch into this pull request by running commands similar to these in the local repository for your personal fork:

git checkout 8253797-jdk8u-dev
git fetch https://git.openjdk.org/jdk8u-dev master
git merge FETCH_HEAD
# if there are conflicts, follow the instructions given by git merge
git commit -m "Merge master"
git push

[jmtd]

Oddly we got this approved a week ago. I've rebased since, so I've just double-checked that the patch is clean (yes)

/integrate

[openjdk]

Going to push as commit b2619cf.

[openjdk]

@jmtd Pushed as commit b2619cf.

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