[jdk21u-dev] RFR: 8331560: Refactor Hotspot container detection code so that subsystem delegates to controllers [v4]

[Jan Kratochvil]

> A patch 5 of 7 for: [[21u] Backport intention of 8322420: [Linux] cgroup v2: Limits in parent nested control groups are not detected](https://mail.openjdk.org/pipermail/jdk-updates-dev/2025-April/043206.html)
> 
> It has a patch dependency on PR 3 of 7: https://github.com/openjdk/jdk21u-dev/pull/1661
> 
> This backport is not clean:
> 
>  - `src/hotspot/os/linux/cgroupSubsystem_linux.hpp`, `src/hotspot/os/linux/cgroupV1Subsystem_linux.cpp`, `src/hotspot/os/linux/cgroupV1Subsystem_linux.hpp`, `src/hotspot/os/linux/cgroupV2Subsystem_linux.cpp`, `src/hotspot/os/linux/cgroupV2Subsystem_linux.hpp` are missing `CgroupSubsystem::memory_and_swap_usage_in_bytes()` as [JDK-8325139](https://github.com/openjdk/jdk/commit/3d106cb091de6b6ef2a9bf483fb0f5c98c28263c) has not been backported.
> 
>  - `src/hotspot/os/linux/cgroupSubsystem_linux.hpp`, `src/hotspot/os/linux/cgroupV1Subsystem_linux.cpp`, `src/hotspot/os/linux/cgroupV1Subsystem_linux.hpp`, `src/hotspot/os/linux/cgroupV2Subsystem_linux.cpp`, `src/hotspot/os/linux/cgroupV2Subsystem_linux.hpp` are missing `CgroupSubsystem::rss_usage_in_bytes()` and `CgroupSubsystem::cache_usage_in_bytes()` as [JDK-8313083](https://github.com/openjdk/jdk/commit/c96cbe481c86800b76e220374b24b6671984adb7) has not been backported.
> 
> The whole patchset has been tested on CentOS-7.9 (for cgroup v1) and on Fedora 40 (for cgroup v2) for test/hotspot/jtreg/containers.

Jan Kratochvil has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains nine commits:

 - Merge branch 'devmaster' into devmaster-cgroup2reduced1234-conflict
 - Merge remote-tracking branch 'janjdk21u-dev/devmaster-cgroup2reduced1234b' into devmaster-cgroup2reduced1234-conflict
 - 8331560: Refactor Hotspot container detection code so that subsystem delegates to controllers
   
   Reviewed-by: jsjolen, stuefe
 - 8261242: [Linux] OSContainer::is_containerized() returns true when run outside a container
   
   Reviewed-by: stuefe, iklam
 - src/java.base/linux/native/libjava/CgroupMetrics.c:42:(.text+0x11): undefined reference to `JVM_IsContainerized'
    - a patch by Yuri Nesterenko
 - 8333326: Linux Alpine build fails after 8302744
   
   Reviewed-by: sgehwolf, clanger, stuefe
 - 8302744: Refactor Hotspot container detection code
   
   Reviewed-by: jsjolen, stuefe
 - rss/cache fixups.
 - 8331560: Refactor Hotspot container detection code so that subsystem delegates to controllers
   
   Reviewed-by: jsjolen, stuefe

-------------

Changes: https://git.openjdk.org/jdk21u-dev/pull/1662/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1662&range=03
  Stats: 570 lines in 8 files changed: 325 ins; 81 del; 164 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/1662.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/1662/head:pull/1662

PR: https://git.openjdk.org/jdk21u-dev/pull/1662