[CRIU] [PATCH 1/2] Re-create cgroups if necessary

[Pavel Emelyanov]

On 06/25/2014 07:06 PM, Serge Hallyn wrote:

> Another complication, btw, will be to do with relative cgroup paths.  I can
> probably abstract that behind the cgmanager abstraction when I add that,
> but idea is - if I checkpointed u1 on the host, in /cpuset/lxc/u1, and now
> restart it inside a nested container, then it should be restarted at
> /cpuset/lxc/somecontainer/lxc/u1, perhaps even /cpuset/lxc/u1/lxc/u1.

How about do it two-step.

First, on dump all cgroup paths are dumped relative to root task groups.
It's not so yet, but since we in -rc we can change that. Next, on restore
we tell the --cgroup-root $path option that would prepend $path to all
cgroup paths from the image.

With your example the /lxc/u1 would get trimmed from tasks' cgroup paths on
dump and on restore you'd be able to say --cgroup-root /cpuset/lxc/u1/lxc/u1.

Thanks,
Pavel