Re: [PATCH v4 4/4] drm/i915: Use __sg_alloc_table_from_pages for userptr allocations

From: Chris Wilson
Date: Mon Nov 14 2016 - 04:53:16 EST


On Fri, Nov 11, 2016 at 12:36:13PM +0000, Tvrtko Ursulin wrote:
> From: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx>
>
> With the addition of __sg_alloc_table_from_pages we can control
> the maximum coallescing size and eliminate a separate path for
> allocating backing store here.
>
> Similar to 871dfbd67d4e ("drm/i915: Allow compaction upto
> SWIOTLB max segment size") this enables more compact sg lists to
> be created and so has a beneficial effect on workloads with many
> and/or large objects of this class.
>
> v2:
> * Rename helper to i915_sg_segment_size and fix swiotlb override.
> * Commit message update.
>
> v3:
> * Actually include the swiotlb override fix.
>
> v4:
> * Regroup parameters a bit. (Chris Wilson)
>
> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx>
> Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
> Reviewed-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> (v2)
(bump)
Reviewed-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
-Chris

--
Chris Wilson, Intel Open Source Technology Centre