Re: [Intel-gfx] [PATCH 1/2] drm/i915: Allow overlapping userptr objects

2014-07-23 Thread Tvrtko Ursulin
On 07/23/2014 03:34 PM, Daniel Vetter wrote: On Wed, Jul 23, 2014 at 02:23:53PM +0100, Tvrtko Ursulin wrote: I think it would be good to add some more tests to cover the tracking "handover" between the interval tree and linear list to ensure invalidation still works correctly in non-trivial cas

Re: [Intel-gfx] [PATCH 1/2] drm/i915: Allow overlapping userptr objects

2014-07-23 Thread Daniel Vetter
On Wed, Jul 23, 2014 at 02:23:53PM +0100, Tvrtko Ursulin wrote: > Looks fine. Performance impact is potentially big as we discussed but I > suppose we can leave that for later if an issue. So: > > Reviewed-by: Tvrtko Ursulin Merged, thanks for patch and review. > I think it would be good to add

Re: [Intel-gfx] [PATCH 1/2] drm/i915: Allow overlapping userptr objects

2014-07-23 Thread Tvrtko Ursulin
On 07/21/2014 01:21 PM, Chris Wilson wrote: Whilst I strongly advise against doing so for the implicit coherency issues between the multiple buffer objects accessing the same backing store, it nevertheless is a valid use case, akin to mmaping the same file multiple times. The reason why we forb

[Intel-gfx] [PATCH 1/2] drm/i915: Allow overlapping userptr objects

2014-07-21 Thread Chris Wilson
Whilst I strongly advise against doing so for the implicit coherency issues between the multiple buffer objects accessing the same backing store, it nevertheless is a valid use case, akin to mmaping the same file multiple times. The reason why we forbade it earlier was that our use of the interval

Re: [Intel-gfx] [PATCH 1/2] drm/i915: Allow overlapping userptr objects

2014-07-10 Thread Daniel Vetter
On Thu, Jul 10, 2014 at 10:21:43AM +0100, Chris Wilson wrote: > Whilst I strongly advise against doing so for the implicit coherency > issues between the multiple buffer objects accessing the same backing > store, it nevertheless is a valid use case, akin to mmaping the same > file multiple times.

Re: [Intel-gfx] [PATCH 1/2] drm/i915: Allow overlapping userptr objects

2014-07-10 Thread Chris Wilson
On Thu, Jul 10, 2014 at 01:26:53PM +0100, Tvrtko Ursulin wrote: > Too bad that on first overlapping object the whole process goes into > "slow mode". I wonder what would benchmarking say to that. > > Perhaps we could still use interval tree but add another layer of > indirection where ranges would

Re: [Intel-gfx] [PATCH 1/2] drm/i915: Allow overlapping userptr objects

2014-07-10 Thread Tvrtko Ursulin
On 07/10/2014 10:21 AM, Chris Wilson wrote: Whilst I strongly advise against doing so for the implicit coherency issues between the multiple buffer objects accessing the same backing store, it nevertheless is a valid use case, akin to mmaping the same file multiple times. The reason why we forb

[Intel-gfx] [PATCH 1/2] drm/i915: Allow overlapping userptr objects

2014-07-10 Thread Chris Wilson
Whilst I strongly advise against doing so for the implicit coherency issues between the multiple buffer objects accessing the same backing store, it nevertheless is a valid use case, akin to mmaping the same file multiple times. The reason why we forbade it earlier was that our use of the interval