[PATCH] drm/i915: Before pageflip, also wait for shared dmabuf fences.

[Michel Dänzer]

On 31/10/16 05:00 PM, Christian König wrote:
> Am 31.10.2016 um 07:44 schrieb Michel Dänzer:
>> On 29/10/16 10:58 PM, Mike Lothian wrote:
>>> I turned on vsync and everything works great in tomb raider
>>>
>>> :D
>>>
>>> Thanks again to everyone who made this possible
>>>
>>> On Fri, 28 Oct 2016 at 19:37 Mike Lothian <mike at fireburn.co.uk
>>> <mailto:mike at fireburn.co.uk>> wrote:
>>>
>>>      Hi Mario
>>>
>>>      That fixes the tearing, it's been replaced with a strange stutter,
>>>      like it's only showing half the number of frames being reported -
>>>      it's really noticeable in tomb raider
>> I wonder if the stutter might be due to the dGPU writing another frame
>> before the iGPU is done processing the previous one. Christian, does the
>> amdgpu scheduler wait for shared fences of shared BOs to signal before
>> submitting jobs using them to the GPU?
> 
> Yeah, that should work. We wait for both the exclusive as well as all
> shared fences before CS or pageflip.
> 
> Only on CS we filter the shared fences so that we don't necessary wait
> for submissions from the same process.

Note that it can be the same process (Xorg) in the RandR 1.4 multihead
case. But it sounds like Mike's stutter can't be due to the issue I was
thinking of.


-- 
Earthling Michel Dänzer               |               http://www.amd.com
Libre software enthusiast             |             Mesa and X developer