Date:   Thu, 13 Jan 2022 16:11:23 -0500
From:   Daniel Jordan <daniel.m.jordan@oracle.com>
To:     Tejun Heo <tj@kernel.org>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        Alexander Duyck <alexanderduyck@fb.com>,
        Alex Williamson <alex.williamson@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Ben Segall <bsegall@google.com>,
        Cornelia Huck <cohuck@redhat.com>,
        Dan Williams <dan.j.williams@intel.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Herbert Xu <herbert@gondor.apana.org.au>,
        Ingo Molnar <mingo@redhat.com>,
        Jason Gunthorpe <jgg@nvidia.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Josh Triplett <josh@joshtriplett.org>,
        Michal Hocko <mhocko@suse.com>, Nico Pache <npache@redhat.com>,
        Pasha Tatashin <pasha.tatashin@soleen.com>,
        Steffen Klassert <steffen.klassert@secunet.com>,
        Steve Sistare <steven.sistare@oracle.com>,
        Tim Chen <tim.c.chen@linux.intel.com>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        linux-mm@kvack.org, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org
Subject: Re: [RFC 15/16] sched/fair: Account kthread runtime debt for CFS
 bandwidth
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On Thu, Jan 13, 2022 at 04:08:57PM -0500, Daniel Jordan wrote:
> On Wed, Jan 12, 2022 at 10:18:16AM -1000, Tejun Heo wrote:
> > If we're gonna do this, let's please do it right and make weight based
> > control work too. Otherwise, its usefulness is pretty limited.
> 
> Ok, understood.
> 
> Doing it as presented is an incremental step and all that's required for
> this.  I figured weight could be added later with the first user that
> actually needs it.
> 
> I did prototype weight too, though, just to see if it was all gonna work
> together, so given how the discussion elsewhere in the thread is going,
> I might respin the scheduler part of this with another use case and
> weight-based control included.
> 
> I got this far, do the interface and CFS skeleton seem sane?  Both are

s/CFS/CFS bandwidth/

> basically unchanged with weight-based control included, the weight parts
> are just more code on top.
> 
> Thanks for looking.