Rework TTMs busy handling

[Christian König]

Am 09.01.24 um 09:14 schrieb Thomas Hellström:
> Hi, Christian
>
> On Tue, 2024-01-09 at 08:47 +0100, Christian König wrote:
>> Hi guys,
>>
>> 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.
>>
>> Zack pointed out that some removed VMWGFX code was brought back
>> because
>> of rebasing, fixed in this version.
>>
>> Intel CI seems to be happy with those patches, so any more comments?
> Looks like Xe changes are missing? (xe is now in drm-tip).
>
> 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.

Going to take a look at XE as well, thanks for the notice.

Regards,
Christian.

>
> /Thomas
>
>
>> Regards,
>> Christian.
>>
>>