RFR: 8343191: Cgroup v1 subsystem fails to set subsystem path [v3]

[Sergey Chernyshev]

On Mon, 2 Dec 2024 10:47:01 GMT, Severin Gehwolf <sgehwolf at openjdk.org> wrote:

> And after the patch this would become this, right?
> 
> ```
> /sys/fs/cgroup/cpu,cpuacct/system.slice/garden.service/garden/bad/2f57368b-0eda-4e52-64d8-af5c
> /sys/fs/cgroup/cpu,cpuacct/
> ```

It depends on whether it was a subgroup in the initial path. If `bad/2f57368b-0eda-4e52-64d8-af5c` is the subgroup, the reduction will be

/sys/fs/cgroup/cpu,cpuacct/system.slice/garden.service/garden/bad/2f57368b-0eda-4e52-64d8-af5c
/sys/fs/cgroup/cpu,cpuacct/bad/2f57368b-0eda-4e52-64d8-af5c
/sys/fs/cgroup/cpu,cpuacct/bad
/sys/fs/cgroup/cpu,cpuacct/

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

PR Review Comment: https://git.openjdk.org/jdk/pull/21808#discussion_r1865663436