On Wed, Dec 04, 2013 at 09:59:09AM +0000, Chris Wilson wrote: > It is useful to assert that if the object is bound, then it must have > its pages pinned to prevent the shrinker from reaping its backing store. > This is even more useful with the introduction of real-ppgtt whereupon > we may have the object bound into several vma, with each instance > pinning the backing store. This assertion breaks down during unbind > where we unpinned the backing store before decoupling the vma binding. > This can be fixed with a trivial reording of the unbind sequence, which > reinforces the > > pin pages > bind to vma > ... > unbind from vma > unpin pages > > concept. > > v2: Bonus comment > > Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > Cc: Ben Widawsky <ben@xxxxxxxxxxxx> > Reviewed-by: Ben Widawsky <ben@xxxxxxxxxxxx> > Tested-by: Ben Widawsky <ben@xxxxxxxxxxxx> Queued for -next, thanks for the patch. -Daniel > --- > drivers/gpu/drm/i915/i915_gem.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c > index 6312d61f5198..9b805f0e8387 100644 > --- a/drivers/gpu/drm/i915/i915_gem.c > +++ b/drivers/gpu/drm/i915/i915_gem.c > @@ -2755,7 +2755,6 @@ int i915_vma_unbind(struct i915_vma *vma) > vma->unbind_vma(vma); > > i915_gem_gtt_finish_object(obj); > - i915_gem_object_unpin_pages(obj); > > list_del(&vma->mm_list); > /* Avoid an unnecessary call to unbind on rebind. */ > @@ -2763,7 +2762,6 @@ int i915_vma_unbind(struct i915_vma *vma) > obj->map_and_fenceable = true; > > drm_mm_remove_node(&vma->node); > - > i915_gem_vma_destroy(vma); > > /* Since the unbound list is global, only move to that list if > @@ -2771,6 +2769,12 @@ int i915_vma_unbind(struct i915_vma *vma) > if (list_empty(&obj->vma_list)) > list_move_tail(&obj->global_list, &dev_priv->mm.unbound_list); > > + /* And finally now the object is completely decoupled from this vma, > + * we can drop its hold on the backing storage and allow it to be > + * reaped by the shrinker. > + */ > + i915_gem_object_unpin_pages(obj); > + > return 0; > } > > -- > 1.8.5 > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@xxxxxxxxxxxxxxxxxxxxx > http://lists.freedesktop.org/mailman/listinfo/intel-gfx -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
