[PATCH RFC 2/5] cgroup: Add mechanism to register vendor specific DRM devices

[Koenig, Christian]

Hi Harish,

Am 26.11.18 um 21:59 schrieb Kasiviswanathan, Harish:
> Thanks Tejun,Eric and Christian for your replies.
>
> We want GPUs resource management to work seamlessly with containers and container orchestration. With the Intel / bpf based approach this is not possible.

I think one lesson learned is that we should describe this goal in the 
patch covert letter when sending it out. That could have avoid something 
like have of the initial confusion.

>  From your response we gather the following. GPU resources need to be abstracted. We will send a new proposal in same vein. Our current thinking is to start with a single abstracted resource and build a framework that can be expanded to include additional resources. We plan to start with “GPU cores”. We believe all GPUs have some concept of cores or compute unit.

Sounds good, just one comment on creating a framework: Before doing 
something like this think for a moment if it doesn't make sense to 
rather extend the existing cgroup framework. That approach usually makes 
more sense because you rarely need something fundamentally new.

Regards,
Christian.

>
> Your feedback is highly appreciated.
>
> Best Regards,
> Harish
>
>
>
> From: amd-gfx <amd-gfx-bounces at lists.freedesktop.org> on behalf of Tejun Heo <tj at kernel.org>
> Sent: Tuesday, November 20, 2018 5:30 PM
> To: Ho, Kenny
> Cc: cgroups at vger.kernel.org; intel-gfx at lists.freedesktop.org; y2kenny at gmail.com; amd-gfx at lists.freedesktop.org; dri-devel at lists.freedesktop.org
> Subject: Re: [PATCH RFC 2/5] cgroup: Add mechanism to register vendor specific DRM devices
>    
>
> Hello,
>
> On Tue, Nov 20, 2018 at 10:21:14PM +0000, Ho, Kenny wrote:
>> By this reply, are you suggesting that vendor specific resources
>> will never be acceptable to be managed under cgroup?  Let say a user
> I wouldn't say never but whatever which gets included as a cgroup
> controller should have clearly defined resource abstractions and the
> control schemes around them including support for delegation.  AFAICS,
> gpu side still seems to have a long way to go (and it's not clear
> whether that's somewhere it will or needs to end up).
>
>> want to have similar functionality as what cgroup is offering but to
>> manage vendor specific resources, what would you suggest as a
>> solution?  When you say keeping vendor specific resource regulation
>> inside drm or specific drivers, do you mean we should replicate the
>> cgroup infrastructure there or do you mean either drm or specific
>> driver should query existing hierarchy (such as device or perhaps
>> cpu) for the process organization information?
>>
>> To put the questions in more concrete terms, let say a user wants to
>> expose certain part of a gpu to a particular cgroup similar to the
>> way selective cpu cores are exposed to a cgroup via cpuset, how
>> should we go about enabling such functionality?
> Do what the intel driver or bpf is doing?  It's not difficult to hook
> into cgroup for identification purposes.
>
> Thanks.
>