Rework TTMs busy handling

[Michel Dänzer]

On 2024-01-09 09:34, Christian König wrote:
> Am 09.01.24 um 09:14 schrieb Thomas Hellström:
>> On Tue, 2024-01-09 at 08:47 +0100, Christian König wrote:
>>>
>>> I'm trying to make this functionality a bit more useful for years now
>>> since we multiple reports that behavior of drivers can be suboptimal
>>> when multiple placements be given.
>>>
>>> So basically instead of hacking around the TTM behavior in the driver
>>> once more I've gone ahead and changed the idle/busy placement list
>>> into idle/busy placement flags. This not only saves a bunch of code,
>>> but also allows setting some placements as fallback which are used if
>>> allocating from the preferred ones didn't worked.
>>
>> I also have some doubts about the naming "idle" vs "busy", since an
>> elaborate eviction mechanism would probably at some point want to check
>> for gpu idle vs gpu busy, and this might create some confusion moving
>> forward for people confusing busy as in memory overcommit with busy as
>> in gpu activity.
>>
>> I can't immediately think of something better, though.
> 
> Yeah, I was wondering about that as well. Especially since I wanted to add some more flags in the future when for example a bandwidth quota how much memory can be moved in/out is exceeded.
> 
> Something like phase1, phase2, phase3 etc..., but that's also not very descriptive either.

Maybe something like "desired" vs "fallback"?


-- 
Earthling Michel Dänzer            |                  https://redhat.com
Libre software enthusiast          |         Mesa and Xwayland developer