Re: [PATCH v8 06/16] sched/core: uclamp: Extend sched_setattr() to support utilization clamping

[Peter Zijlstra]

On Tue, May 07, 2019 at 12:13:47PM +0100, Patrick Bellasi wrote:
> On 17-Apr 15:26, Suren Baghdasaryan wrote:
> > On Tue, Apr 2, 2019 at 3:42 AM Patrick Bellasi <patrick.bellasi@xxxxxxx> wrote:

> > > @@ -1056,6 +1100,13 @@ static void __init init_uclamp(void)
> > >  #else /* CONFIG_UCLAMP_TASK */
> > >  static inline void uclamp_rq_inc(struct rq *rq, struct task_struct *p) { }
> > >  static inline void uclamp_rq_dec(struct rq *rq, struct task_struct *p) { }
> > > +static inline int uclamp_validate(struct task_struct *p,
> > > +                                 const struct sched_attr *attr)
> > > +{
> > > +       return -ENODEV;
> > 
> > ENOSYS might be more appropriate?
> 
> Yep, agree, thanks!

No, -ENOSYS (see the comment) is special in that it indicates the whole
system call is unavailable; that is most certainly not the case!