On Wed, 1 Feb 2012 13:13:44 +0100, Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> wrote: > On Wed, Feb 01, 2012 at 11:55:44AM +0000, Chris Wilson wrote: > > On Wed, 1 Feb 2012 11:38:35 +0100, Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> wrote: > > > The drivers currently check in set_property whether the property is > > > unchanged. move this check into the core and do not bother the drivers > > > with checking for unchanged properties. > > > > This patch seems to have functional side-effects beyond the description. > > > > For example, > > > diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c > > > index db3b461..0024b59 100644 > > > --- a/drivers/gpu/drm/i915/intel_dp.c > > > +++ b/drivers/gpu/drm/i915/intel_dp.c > > > @@ -2223,9 +2223,6 @@ intel_dp_set_property(struct drm_connector *connector, > > > int i = val; > > > bool has_audio; > > > > > > - if (i == intel_dp->force_audio) > > > - return 0; > > > - > > > > Here we are checking against the current value of the intel_dp, which > > may in theory be modified elsewhere as well, and avoiding the modeswitch > > if it is unnecessary. > > In case of force_audio I just checked that the current value is not > changed elsewhere, but I must admit that I haven't checked this for > all other properties. Would the patch be ok if I review for side > effects? > > BTW if someone changes the underlying variable of a property outside > of the .set_property callback there are likely problems elsewhere > because without calling drm_connector_property_set_value the values > of the variable and the property backing store will be inconsistent. > The calls to drm_connector_property_set_value in turn are quite easy > reviewable, those are very few. Sure, it just jumped out as being not in the same pattern as the rest. I'd break out the ones that are different, like intel_dp, into their own patch so that the above analysis can be recorded along with the change and that we have something easy to bisect/change-our-minds about later. ;-) -Chris -- Chris Wilson, Intel Open Source Technology Centre _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
