[Devel] [RFC rh7] ve: cgroups -- Allow to attach non-self into ve cgroups

[Cyrill Gorcunov]

On Tue, Jun 16, 2015 at 07:44:08PM +0300, Kirill Tkhai wrote:
> > 
> > We gonna move only one task in container start time so I think
> > this is not critical in timing.
> > 
> > As to #2 -- yes, I think rcu-readlock with sync should do the trick.
> > Also I need to check in details what Vladimir suggested, maybe this
> > will work even better?
> 
> Maybe it better, but it allows a situation, when parent's task_ve is
> !ve0, and child's is ve0 for a some time. I'm afraid if there are hidden
> places, which may work wrong because of this.
> 
> If we have any problems because of this, the solution is good.

OK. Gimme sometime (util tomorrow probably) to think of. This issue
not critical at the moment because we know that we're moving one
task only (from vzctl). So we can investigate.

>  
> > > Hm. How about stop_machine? It solves all of the problems. Also, it shouldn't
> > > worsen performance, because this action is rare.
> > 
> > iirc stop-machine is a big hammer :/