[Intel-gfx] [PATCH 1/3] drm/i915/display: Do not schedule DRRS work thread when it is not active

[Souza, Jose]

On Fri, 2022-04-29 at 19:00 +0300, Ville Syrjälä wrote:
> On Thu, Apr 28, 2022 at 02:10:56PM -0700, José Roberto de Souza wrote:
> > Frontbuffer updates were scheduling the execution of DRRS work thread
> > even if DRRS is not active.
> > There was no issues with it because intel_drrs_downclock_work() checks
> > if DRRS is active but there is no reason to keep scheduling this work
> > thread and wasting CPU time.
> > 
> > Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_drrs.c | 5 +++++
> >  1 file changed, 5 insertions(+)
> > 
> > diff --git a/drivers/gpu/drm/i915/display/intel_drrs.c b/drivers/gpu/drm/i915/display/intel_drrs.c
> > index 166caf293f7bc..04bc296761be0 100644
> > --- a/drivers/gpu/drm/i915/display/intel_drrs.c
> > +++ b/drivers/gpu/drm/i915/display/intel_drrs.c
> > @@ -236,6 +236,11 @@ static void intel_drrs_frontbuffer_update(struct drm_i915_private *dev_priv,
> >  		else
> >  			crtc->drrs.busy_frontbuffer_bits &= ~frontbuffer_bits;
> >  
> > +		if (!intel_drrs_is_active(crtc)) {
> > +			mutex_unlock(&crtc->drrs.mutex);
> > +			continue;
> > +		}
> 
> Should be impossible due to crtc->drrs.frontbuffer_bits==0.

Yep, my bad this patch is not needed.
Can you review the remaining?

I have one more patch to this series that avoids DP link configuration change during seamless mode change, when possible.
Planning to send new version with this patch any other changes that you request.

thanks

> 
> > +
> >  		/* flush/invalidate means busy screen hence upclock */
> >  		intel_drrs_set_state(crtc, DRRS_REFRESH_RATE_HIGH);
> >  
> > -- 
> > 2.36.0
>