[Intel-gfx] [PATCH 30/66] drm/i915: Getter/setter for object attributes

[Daniel Vetter]

On Mon, Jul 01, 2013 at 03:59:51PM -0700, Ben Widawsky wrote:
> On Mon, Jul 01, 2013 at 09:08:58PM +0200, Daniel Vetter wrote:
> > On Mon, Jul 1, 2013 at 8:43 PM, Daniel Vetter <daniel at ffwll.ch> wrote:
> > >> All of this is addressed in future patches. As we've discussed, I think
> > >> I'll have to respin it anyway, so I'll name it as such upfront. To me it
> > >> felt a little weird to start calling things "ggtt" before I made the
> > >> separation.
> > >
> > > I think now that we know what the end result should (more or less at
> > > least) look like we can aim to make it right the first time we touch a
> > > piece of code. That will reduce the churn in the patch series and so
> > > make the beast easier to review.
> > >
> > > Imo foreshadowing (to keep consistent with the "a patch series should
> > > tell a story" analogy) is perfectly fine, and in many cases helps in
> > > understanding the big picture of a large pile of patches.
> > 
> > I've forgotten to add one thing: If you switch these again later on
> > (layz me didn't check for that) it's imo best to stick with those
> > names (presuming they fit, since the gtt_size vs. obj->size
> > disdinction is a rather important one). Again I think now that we know
> > where to go to it's best to get there with as few intermediate steps
> > as possible.
> > -Daniel
> >
> 
> I don't recall object size being very important actually, so I don't
> think the distinction is too important, but I'm just arguing for the
> sake of arguing. With the sg page stuff that Imre did, I think most size
> calculations unrelated to gtt size are there anyway, and most of our mm
> (not page allocation) code should only ever care about the gtt.

The disdinction is only important on gen2/3, which is why you don't recall
it being important ;-)

I think you have two options:
- Trust me that it's indeed important.
- Read up on gen2/3 fencing code and make up your own mind.

Cheers, Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch