8331560: Refactor Hotspot container detection code so that subsystem delegates to controllers

[jerboaa]

Please review this preparatory PR which is an enabler for some bugfix/alignment work (e.g. JDK-8322420). The idea is to delegate limit lookup to controllers (memory, cpu, etc.) from the overarching CgroupSubsystem class. This way we can - once the cg type has been detected - "adjust" a controller's path to the limit files when the controller is being created (on init) and then left alone. In this case, the two preparatory entry points are CgroupUtil::processor_count() taking a version-agnostic CgroupCpuController to do the actual look-up and CgroupMemoryController::read_memory_limit_in_bytes() for the same in terms of memory limits.

This enables setting the contoller's path to the interface files (wherever it might be in the hierarchy of it's original cgroup path), look up the limit and "freeze" the path once it found a - lower - limit.

It also ensures that both cgroup versions return -1 or -2 (OSCONTAINER_ERROR) - in both cases negative - for some notion of unlimited. I.e. it makes the upper bound by the host's physical memory apparent in the version agnostic classes.

Testing:

• GHA
• gtest:cgroupTest tests
• container tests on Linux cgv1 and cgv2 on x86_64

Thoughts?

---

Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
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• Commit message must refer to an issue

Issue

• JDK-8331560: Refactor Hotspot container detection code so that subsystem delegates to controllers (Enhancement - P3)

Reviewers

• Johan Sjölen (@jdksjolen - Reviewer)
• Thomas Stuefe (@tstuefe - Reviewer) ⚠️ Review applies to dcd0554b

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk.git pull/19085/head:pull/19085
$ git checkout pull/19085

Update a local copy of the PR:
$ git checkout pull/19085
$ git pull https://git.openjdk.org/jdk.git pull/19085/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 19085

View PR using the GUI difftool:
$ git pr show -t 19085

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk/pull/19085.diff

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[bridgekeeper]

👋 Welcome back sgehwolf! A progress list of the required criteria for merging this PR into pr/19060 will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

@jerboaa 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:

8331560: Refactor Hotspot container detection code so that subsystem delegates to controllers

Reviewed-by: jsjolen, stuefe

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 10 new commits pushed to the master branch:

• dd74e7f: 8335147: Serial: Refactor TenuredGeneration::promote
• a537e87: 8335530: Java file extension missing in AuthenticatorTest
• 4060b35: 8335298: Fix -Wzero-as-null-pointer-constant warning in G1CardSetContainers
• 9046d7a: 8335390: C2 MergeStores: wrong result with Unsafe
• 318d9ac: 8335369: Fix -Wzero-as-null-pointer-constant warnings in ImmutableOopMapBuilder
• 5fe07b3: 5021949: JSplitPane setEnabled(false) shouldn't be partially functional
• ee4720a: 8333306: gc/arguments/TestParallelGCErgo.java fails when largepage are enabled
• 2f4f6cc: 8317721: RISC-V: Implement CRC32 intrinsic
• 3ca2bcd: 8335060: ClassCastException after JDK-8294960
• 747e1e4: 8334295: CTW: update modules

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]

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

• hotspot-runtime

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[mlbridge]

Webrevs

• 07: Full - Incremental (77cf2ea2)
• 06: Full (dcd0554b)
• 05: Full (30fa6173)
• 04: Full - Incremental (abf0adc6)
• 03: Full (6aff2076)
• 02: Full (e177a086)
• 01: Full (5d20a2d5)
• 00: Full (3769ef38)

[openjdk]

@jerboaa this pull request can not be integrated into pr/19060 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 jdk-8331560-cgroup-controller-delegation
git fetch https://git.openjdk.org/jdk.git pr/19060
git merge FETCH_HEAD
# resolve conflicts and follow the instructions given by git merge
git commit -m "Merge pr/19060"
git push

[jankratochvil]

There is the diamond inheritance problem. I am providing a patch, it would be too much clicking in the Github review.
diamond.patch.txt

[jdksjolen]

Hi,

Some more review work here. Unfortunately, mostly nits. I'll take a more big-picture look next.

[jerboaa]

Thanks for the review. Updated the patch!

[jdksjolen]

Hi! Some more review comments.

[jerboaa]

Updated the patch with your suggestions. Thanks!

[tstuefe]

This has been shaping up nicely. From my point of view, this is good to go. Leave it up to @jdksjolen to add any more suggestions.

[jerboaa]

Thanks for the review, Thomas!

[jdksjolen]

I went through it again, LGTM. Nice!

[jerboaa]

Thanks for the reviews!

[jerboaa]

/integrate

[openjdk]

Going to push as commit 153b12b.
Since your change was applied there have been 11 commits pushed to the master branch:

• 685e587: 8334816: compiler/c2/irTests/TestIfMinMax.java fails after 8334629
• dd74e7f: 8335147: Serial: Refactor TenuredGeneration::promote
• a537e87: 8335530: Java file extension missing in AuthenticatorTest
• 4060b35: 8335298: Fix -Wzero-as-null-pointer-constant warning in G1CardSetContainers
• 9046d7a: 8335390: C2 MergeStores: wrong result with Unsafe
• 318d9ac: 8335369: Fix -Wzero-as-null-pointer-constant warnings in ImmutableOopMapBuilder
• 5fe07b3: 5021949: JSplitPane setEnabled(false) shouldn't be partially functional
• ee4720a: 8333306: gc/arguments/TestParallelGCErgo.java fails when largepage are enabled
• 2f4f6cc: 8317721: RISC-V: Implement CRC32 intrinsic
• 3ca2bcd: 8335060: ClassCastException after JDK-8294960
• ... and 1 more: https://git.openjdk.org/jdk/compare/0a6ffa57954ddf4f92205205a5a1bada813d127a...master

Your commit was automatically rebased without conflicts.

[openjdk]

@jerboaa Pushed as commit 153b12b.

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