[Intel-gfx] [PATCH v2] drm/i915: Limit C-states when waiting for the active request

[Chris Wilson]

Quoting Chris Wilson (2018-07-30 13:25:03)
> Quoting Chris Wilson (2018-07-30 13:14:09)
> > +               if (!pm_qos &&
> > +                   i915_seqno_passed(intel_engine_get_seqno(rq->engine),
> > +                                     wait.seqno - 1)) {
> > +                       pm_qos = kzalloc(sizeof(*pm_qos),
> > +                                        GFP_NOWAIT | __GFP_NOWARN);
> > +                       if (pm_qos) {
> > +                               pm_qos_add_request(&pm_qos->req,
> > +                                                  PM_QOS_CPU_DMA_LATENCY,
> > +                                                  50);
> 
> Ho hum, it should also then complain about the blocking notifier
> here. Let's see how observant it is...

Though that was kind of the intention as we could afford to lose a bit
of time before sleeping, so I don't think the blocking notifier itself
is a big deal... It would be a bit of a nuisance to avoid, the easiest
might be to reuse the work.
-Chris