[PATCH 2/2] drm/i915: use drm_mm_remove_node instead of put_block

[Daniel Vetter]

On Mon, Jul 01, 2013 at 10:21:57PM +0200, David Herrmann wrote:
> Hi
> 
> On Mon, Jul 1, 2013 at 10:05 PM, Daniel Vetter <daniel.vetter at ffwll.ch> wrote:
> > When converting to the preallocated drm_mm_node interfaces in
> >
> > commit dc9dd7a20fde95aa81a8307cde79c2dff9f83f3d
> > Author: Chris Wilson <chris at chris-wilson.co.uk>
> > Date:   Fri Dec 7 20:37:07 2012 +0000
> >
> >     drm/i915: Preallocate the drm_mm_node prior to manipulating the GTT drm_mm
> >
> > only the allocation side was converted, but not the freeing. Fix this
> > up.
> >
> > Note that the only difference between put_block and remove_node is
> > that the former fills up the preallocation cache. Which we don't need
> > anyway and hence is just wasted space.
> >
> > Cc: Chris Wilson <chris at chris-wilson.co.uk>
> > Cc: Ben Widawsky <ben at bwidawsk.net>
> > Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
> > ---
> >  drivers/gpu/drm/i915/i915_gem.c | 6 +++---
> >  1 file changed, 3 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> > index 4200c32..30fd694 100644
> > --- a/drivers/gpu/drm/i915/i915_gem.c
> > +++ b/drivers/gpu/drm/i915/i915_gem.c
> > @@ -2620,7 +2620,7 @@ i915_gem_object_unbind(struct drm_i915_gem_object *obj)
> >         /* Avoid an unnecessary call to unbind on rebind. */
> >         obj->map_and_fenceable = true;
> >
> > -       drm_mm_put_block(obj->gtt_space);
> > +       drm_mm_remove_node(obj->gtt_space);
> 
> kfree(obj->gtt_space);
> 
> >         obj->gtt_space = NULL;
> >         obj->gtt_offset = 0;
> >
> > @@ -3137,14 +3137,14 @@ search_free:
> >         }
> >         if (WARN_ON(!i915_gem_valid_gtt_space(dev, node, obj->cache_level))) {
> >                 i915_gem_object_unpin_pages(obj);
> > -               drm_mm_put_block(node);
> > +               drm_mm_remove_node(node);
> 
> kfree(node);
> 
> >                 return -EINVAL;
> >         }
> >
> >         ret = i915_gem_gtt_prepare_object(obj);
> >         if (ret) {
> >                 i915_gem_object_unpin_pages(obj);
> > -               drm_mm_put_block(node);
> > +               drm_mm_remove_node(node);
> 
> kfree(node);

Yeah, I fail ...

> drm_mm_remove_node() does unlink the node but not remove it. Btw., I
> have these fixes in my series, too. I will push it later and write the
> git-link to #dri-devel.

We have patches in-flight to convert over to embedded drm_mm_nodes anyway,
so I guess that part will solve itself automatically.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch