`configs.Cgroup` contains the configuration used to create cgroups. This
configuration must be saved to disk, since it's required to restore the
cgroup manager that was used to create the cgroups.
Add method to get cgroup configuration from cgroup Manager to allow API users
save it to disk and restore a cgroup manager later.
fixes#2176
Signed-off-by: Julio Montes <julio.montes@intel.com>
Implemented `runc ps` for cgroup v2 , using a newly added method `m.GetUnifiedPath()`.
Unlike the v1 implementation that checks `m.GetPaths()["devices"]`, the v2 implementation does not require the device controller to be available.
Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>