Re: [PATCH, v3 2/2] cgroups: introduce timer slack subsystem

[Matt Helsley <matthltc@us.ibm.com>]

On Wed, Feb 02, 2011 at 03:23:15PM -0800, Paul Menage wrote:
> On Wed, Feb 2, 2011 at 12:47 PM, Kirill A. Shutsemov
<kirill@shutemov.name> wrote:
> > +static int tslack_write_range(struct cgroup *cgroup, struct cftype *cft,
> > +               u64 val)
> > +{
> > +       struct timer_slack_cgroup *tslack_cgroup;
> > +       struct cgroup_iter it;
> > +       struct task_struct *task;
> > +
> > +       if (!val)
> > +               return -EINVAL;
> > +
> > +       tslack_cgroup = cgroup_to_tslack_cgroup(cgroup);
> > +       switch (cft->private) {
> > +       case TIMER_SLACK_MIN:
> > +               if (val > tslack_cgroup->max_slack_ns)
> > +                       return -EINVAL;
> > +               tslack_cgroup->min_slack_ns = val;
> > +               break;
> > +       case TIMER_SLACK_MAX:
> > +               if (val < tslack_cgroup->min_slack_ns)
> > +                       return -EINVAL;
> > +               tslack_cgroup->max_slack_ns = val;
> > +               break;
> > +       default:
> > +               BUG();
> > +       }
> > +
> 
> Don't we want to keep the min/max applied hierarchically as well? i.e.
> a child can't set its min/max outside the range of its parents?

That was my expectation as well.

Cheers,
	-Matt Helsley