[Intel-gfx] [PATCH 1/3] drm: Track drm_mm nodes with an interval tree

[David Herrmann]

Hi

On Wed, Oct 21, 2015 at 5:11 PM, Daniel Vetter <daniel at ffwll.ch> wrote:
> On Tue, Oct 06, 2015 at 11:53:09AM +0100, Chris Wilson wrote:
>> In addition to the last-in/first-out stack for accessing drm_mm nodes,
>> we occasionally and in the future often want to find a drm_mm_node by an
>> address. To do so efficiently we need to track the nodes in an interval
>> tree - lookups for a particular address will then be O(lg(N)), where N
>> is the number of nodes in the range manager as opposed to O(N).
>> Insertion however gains an extra O(lg(N)) step for all nodes
>> irrespective of whether the interval tree is in use. For future i915
>> patches, eliminating the linear walk is a significant improvement.
>>
>> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
>> Cc: dri-devel at lists.freedesktop.org
>
> Reviewed-by: Daniel Vetter <daniel.vetter at ffwll.ch>
>
> I guess for simpler merge ordering we can just pull this into drm-intel
> and patch up the vma manager (just need to drop a lot of code and adjust
> the search to use the drm_mm internal_tree nodes) later on.

Agreed.

Acked-by: David Herrmann <dh.herrmann at gmail.com>

Thanks
David