Re: [PATCH] drm/i915: Don't use a special stolen reserve offset

[Daniel Vetter <daniel@ffwll.ch>]

On Thu, Jul 04, 2013 at 11:24:46PM +0200, Daniel Vetter wrote:
> On Thu, Jul 04, 2013 at 12:42:15PM -0700, Ben Widawsky wrote:
> > Setting the node directly is good enough. We don't need a special value
> > to store the gtt_offset, and we no longer have the pointer to tuck
> > things away neatly.
> > 
> > This is temporarily broken since:
> > commit 7dedae28b41000539b6c18bcf72107c97e4937e4
> > Author: Ben Widawsky <ben@bwidawsk.net>
> > Date:   Wed Jul 3 14:45:24 2013 -0700
> > 
> >     drm/i915: Use gtt_space->start for stolen reservation
> > 
> > However with no userspace currently, the bisection problem shouldn't be
> > a concern.
> > 
> > CC: Chris Wilson <chris@chris-wilson.co.uk>
> > Reported-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> > Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
> > ---
> >  drivers/gpu/drm/i915/i915_drv.h        | 1 -
> >  drivers/gpu/drm/i915/i915_gem_gtt.c    | 1 -
> >  drivers/gpu/drm/i915/i915_gem_stolen.c | 8 ++++++--
> >  3 files changed, 6 insertions(+), 4 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> > index ea86ad6..b9e8ba1 100644
> > --- a/drivers/gpu/drm/i915/i915_drv.h
> > +++ b/drivers/gpu/drm/i915/i915_drv.h
> > @@ -1201,7 +1201,6 @@ enum hdmi_force_audio {
> >  	HDMI_AUDIO_ON,			/* force turn on HDMI audio */
> >  };
> >  
> > -#define I915_GTT_RESERVED (ULONG_MAX)
> >  #define I915_GTT_OFFSET_NONE ((u32)-1)
> >  
> >  struct drm_i915_gem_object_ops {
> > diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
> > index f075831..c0ca103 100644
> > --- a/drivers/gpu/drm/i915/i915_gem_gtt.c
> > +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
> > @@ -632,7 +632,6 @@ void i915_gem_setup_global_gtt(struct drm_device *dev,
> >  		DRM_DEBUG_KMS("reserving preallocated space: %lx + %zx\n",
> >  			      i915_gem_obj_ggtt_offset(obj), obj->base.size);
> >  
> > -		BUG_ON(obj->gtt_space->start != I915_GTT_RESERVED);
> 
> I've thought we've agreed on a WARN_ON(!drm_mm_node_allocated); here?

WARN_ON(drm_mm_node_allocated); to be precise ;-)
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch