[libvirt] [PATCH 9/9] qemu_cgroup: assert threading cgroup layout for machine cgroup

[Henning Schild]

On Fri, 26 Feb 2016 12:02:52 +0000
"Daniel P. Berrange" <berrange at redhat.com> wrote:

> On Fri, Feb 26, 2016 at 12:57:38PM +0100, Henning Schild wrote:
> > On Fri, 26 Feb 2016 11:22:07 +0000
> > "Daniel P. Berrange" <berrange at redhat.com> wrote:
> >   
> > > On Tue, Feb 23, 2016 at 04:58:44PM +0100, Henning Schild wrote:  
> > > > Make sure the thread related controls of the machine cgroup
> > > > never get any tasks assigned.
> > > > 
> > > > Signed-off-by: Henning Schild <henning.schild at siemens.com>
> > > > ---
> > > >  src/qemu/qemu_cgroup.c | 14 ++++++++++++--
> > > >  1 file changed, 12 insertions(+), 2 deletions(-)    
> > > 
> > > NACK This also won't work for same reason as previous patch  
> > 
> > Having that in place can still be useful after we have sorted out
> > the random result of what systemd gave us.
> > Is the general idea of such an assertion a good idea, and should i
> > adopt it according to comments?
> > At the moment i just used the assertion mask in the only code-path
> > that adds tasks within libvirt. If we have to deal with
> > manipulation from the outside, it might be a good idea to introduce
> > more assertions based on the mask.  
> 
> Without patch 4 though, there's nowhere you can put this afaict.

After moving the pid to the emulator cgroup, i can assert that the
parent is now empty and then put it in place. It would assert libvirt
itself does not use the parent group somewhen in the future.

> 
> 
> Regards,
> Daniel