[jdk8u-dev] RFR: 8239785: Cgroups: Incorrect detection logic on old systems in hotspot [v3]

[Jonathan Dowland]

> This is a backport of add18914fb1294999877b563c734a25b4c17b922 for cgroups v2 support injdk8u-dev, via the 11u backport.
> 
> It does not apply clean:
> 
>  * context issues for changes made for the different approach for logging in 8u
>  * copyright lines
> 
> Small amount of re-working of new code that used `log_trace`/`log_debug` to use the 8u approach.

Jonathan Dowland has updated the pull request incrementally with one additional commit since the last revision:

  Move test to a more 8u-appropriate location
  
  Container (cgroups, docker) tests in 8u reside in
  hotspot/test/runtime/containers

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

Changes:
  - all: https://git.openjdk.org/jdk8u-dev/pull/135/files
  - new: https://git.openjdk.org/jdk8u-dev/pull/135/files/880244fd..9af9bd47

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk8u-dev&pr=135&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk8u-dev&pr=135&range=01-02

  Stats: 0 lines in 1 file changed: 0 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk8u-dev/pull/135.diff
  Fetch: git fetch https://git.openjdk.org/jdk8u-dev pull/135/head:pull/135

PR: https://git.openjdk.org/jdk8u-dev/pull/135