From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Subject: Re: [PATCH 09/11] drm, cgroup: Introduce lgpu as DRM cgroup resource
Date: Fri, 14 Feb 2020 16:15:28 -0500
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To: Kenny Ho <y2kenny-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Cc: Daniel Vetter <daniel-/w4YWyX8dFk@public.gmane.org>, Jason Ekstrand <jason-fQELhIk9awXprZlt/sZkLg@public.gmane.org>, Kenny Ho <Kenny.Ho-5C7GfCeVMHo@public.gmane.org>, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Maling list - DRI developers <dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org>, amd-gfx mailing list <amd-gfx-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org>, Alex Deucher <alexander.deucher-5C7GfCeVMHo@public.gmane.org>, Christian =?iso-8859-1?Q?K=F6nig?= <christian.koenig-5C7GfCeVMHo@public.gmane.org>, "Kuehling, Felix" <felix.kuehling-5C7GfCeVMHo@public.gmane.org>, "Greathouse, Joseph" <joseph.greathouse-5C7GfCeVMHo@public.gmane.org>, jsparks-WVYJKLFxKCc@public.gmane.org, lkaplan-WVYJKLFxKCc@public.gmane.org, nirmoy.das-5C7GfCeVMHo@public.gmane.org, damon.mcdougall-5C7GfCeVMHo@public.gmane.org, juan.zuniga-anaya-5C7GfCeVMHo@public.gmane.org, Johannes Weiner <hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org>

On Fri, Feb 14, 2020 at 03:28:40PM -0500, Kenny Ho wrote:
> Can you elaborate, per your understanding, how the lgpu weight
> attribute differ from the io.weight you suggested?  Is it merely a

Oh, it's the non-weight part which is problematic.

> formatting/naming issue or is it the implementation details that you
> find troubling?  From my perspective, the weight attribute implements
> as you suggested back in RFCv4 (proportional control on top of a unit
> - either physical or time unit.)
> 
> Perhaps more explicit questions would help me understand what you
> mean. If I remove the 'list' and 'count' attributes leaving just
> weight, is that satisfactory?  Are you saying the idea of affinity or

At least from interface pov, yes, although I think it should be clear
what the weight controls.

> named-resource is banned from cgroup entirely (even though it exists
> in the form of cpuset already and users are interested in having such
> options [i.e. userspace OpenCL] when needed?)
> 
> To be clear, I am not saying no proportional control.  I am saying
> give the user the options, which is what has been implemented.

We can get there if we *really* have to but not from the get-go but
I'd rather avoid affinities if at all possible.

Thanks.

-- 
tejun