[Mesa-dev] [PATCH 1/2] winsys/amdgpu: adjust IB size based on buffer wait time

[Marek Olšák]

On Wed, Apr 20, 2016 at 8:18 PM, Grigori Goronzy <greg at chown.ath.cx> wrote:
> On 2016-04-20 02:20, Nicolai Hähnle wrote:
>>
>> This is just a slight massaging of the patch you sent previously. What
>> happened to the discussion we had about how to do this properly?
>>
>
> This already provides good value as-is and it is (IMHO) reasonably clean, so
> why not include it for the time being? Marek seemed to like the general
> concept as well. I agree that basing IB size on GPU idleness is a great idea
> and I'll look into that, either as an alternative or as an addition to this.
>
> Just a random question: we can count on up to date gfx fence sequence
> numbers being available without any calls into the kernel, right? The winsys
> code makes that conditional and calls into the kernel when no fence pointer
> is available.

Yes, there is a fence buffer you can read to get the latest sequence
numbers for different rings. That buffer might not be updated when IBs
of other process finish though.

Only UVD and VCE don't support user fences.

Marek