[jdk8u-dev] RFR: 8239559: Cgroups: Incorrect detection logic on some systems [v5]

[Jonathan Dowland]

> This is a backport of 53ee0c4963007b86db7979312b81f990e6ce271a via the 11u backport 53ee0c4963007b86db7979312b81f990e6ce271a for cgroups v2 support in jdk8u-dev.
> 
> It isn't clean: context differences in CgroupSubsystemFactory.java around the use of post-8u logging in the original patch.
> 
> I also had to Optional.isEmpty which is not present in 8u's Optional.

Jonathan Dowland has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains one additional commit since the last revision:

  Test fix by Severin. Thanks!

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

Changes:
  - all: https://git.openjdk.org/jdk8u-dev/pull/136/files
  - new: https://git.openjdk.org/jdk8u-dev/pull/136/files/45ec61df..221ef6a5

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk8u-dev&pr=136&range=04
 - incr: https://webrevs.openjdk.org/?repo=jdk8u-dev&pr=136&range=03-04

  Stats: 33 lines in 2 files changed: 24 ins; 0 del; 9 mod
  Patch: https://git.openjdk.org/jdk8u-dev/pull/136.diff
  Fetch: git fetch https://git.openjdk.org/jdk8u-dev pull/136/head:pull/136

PR: https://git.openjdk.org/jdk8u-dev/pull/136