[CRIU] [PATCH 1/2] cg: Add ability to dump custom cgroup properties and skip controllers

[Cyrill Gorcunov]

On Wed, Apr 27, 2016 at 08:30:10AM -0600, Tycho Andersen wrote:
> Hi Cyrill,
> 
> On Wed, Apr 27, 2016 at 11:53:09AM +0300, Cyrill Gorcunov wrote:
> > +
> > +	if (!list_empty(&cgp_list)) {
> > +		pr_info("Custom controllers defined. Zapping compiled in ones.\n");
> > +		INIT_LIST_HEAD(&cgp_predefined_list);
> > +	}
> 
> This means that (IIUC) we can't inherit some properties from the built
> in set. The way I envision using this feature is for when new

Yes, once new specified in command line it means built-ins are
zapped out, so that we have to provide complete set of controllers
and properties in specification.

> controllers or properties are released in the kernel but not in
> upstream CRIU yet (because I haven't updated the list ;-), so I'd
> probably want all the built in ones plus some additional ones.

I don't mind. We will need to provide strategy argument then,
probably inside specification?

> Is there some way we can either add a mode to merge the props provided
> into the props hardcoded? We could just merge by controller, so if you
> specify some props for a controller, you have to specify all the ones
> for that controller, but if you don't say anything about a controller,
> you get the defaults (or you can exclude it with
> --cgroup-exclude-controller when that patch lands).

I'm all opening for suggestion. While not merged we can easily
try out various approaches.