linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Rik van Riel <riel@surriel.com>
To: Peter Zijlstra <peterz@infradead.org>, Tejun Heo <tj@kernel.org>
Cc: Josh Don <joshdon@google.com>, Ingo Molnar <mingo@redhat.com>,
	Juri Lelli <juri.lelli@redhat.com>,
	Vincent Guittot <vincent.guittot@linaro.org>,
	Dietmar Eggemann <dietmar.eggemann@arm.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Ben Segall <bsegall@google.com>, Mel Gorman <mgorman@suse.de>,
	Daniel Bristot de Oliveira <bristot@redhat.com>,
	Paul Turner <pjt@google.com>,
	David Rientjes <rientjes@google.com>,
	Oleg Rombakh <olegrom@google.com>,
	Viresh Kumar <viresh.kumar@linaro.org>,
	Steve Sistare <steven.sistare@oracle.com>,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] sched: cgroup SCHED_IDLE support
Date: Sat, 26 Jun 2021 07:42:27 -0400	[thread overview]
Message-ID: <bd6320bb038f02d2bad0bb07ecf2b23f3cda9167.camel@surriel.com> (raw)
In-Reply-To: <YNWPBDH/mQdojEu9@hirez.programming.kicks-ass.net>

[-- Attachment #1: Type: text/plain, Size: 1171 bytes --]

On Fri, 2021-06-25 at 10:08 +0200, Peter Zijlstra wrote:
> On Wed, Jun 16, 2021 at 11:42:05AM -0400, Tejun Heo wrote:
> > A high-level problem that I see with the proposal is that this
> > would bake
> > the current recursive implementation into the interface. The
> > semantics of
> > the currently exposed interface, at least the weight based part, is
> > abstract
> > and doesn't necessarily dictate how the scheduling is actually
> > performed.
> > Adding this would mean that we're now codifying the current
> > behavior of
> > fully nested scheduling into the interface.
> 
> It's a direct concequence of the hierarchical requirement. The
> approach
> is the only valid one. The other relative controllers that don't do
> this, are simply broken.
> 
> Absolute controllers have it easier, they can be trivially flattened.

I'm pretty sure CFS can be mostly flattened too, just not
trivially :)

Doing the delta_exectime to vruntime accounting in a somewhat
delayed fashion, with never more than one or two timeslices
worth of vruntime at a time being accounted, should make the
flat CFS runqueue model work.

-- 
All Rights Reversed.

[-- Attachment #2: This is a digitally signed message part --]
[-- Type: application/pgp-signature, Size: 488 bytes --]

  parent reply	other threads:[~2021-06-26 11:44 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-08 23:11 [PATCH] sched: cgroup SCHED_IDLE support Josh Don
2021-06-10 12:53 ` Dietmar Eggemann
2021-06-10 19:14   ` Josh Don
2021-06-11 16:43     ` Dietmar Eggemann
2021-06-11 23:34       ` Josh Don
2021-06-15 10:06         ` Dietmar Eggemann
2021-06-15 23:30           ` Josh Don
2021-06-25  9:24           ` Peter Zijlstra
2021-06-16 15:42 ` Tejun Heo
2021-06-17  1:01   ` Josh Don
2021-06-26  9:57     ` Tejun Heo
2021-06-29  4:57       ` Josh Don
2021-06-25  8:08   ` Peter Zijlstra
2021-06-26 10:06     ` Tejun Heo
2021-06-26 11:42     ` Rik van Riel [this message]
2021-06-25  8:14 ` Peter Zijlstra
2021-06-26  0:18   ` Josh Don
2021-06-25  8:20 ` Peter Zijlstra
2021-06-26  0:35   ` Josh Don

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=bd6320bb038f02d2bad0bb07ecf2b23f3cda9167.camel@surriel.com \
    --to=riel@surriel.com \
    --cc=bristot@redhat.com \
    --cc=bsegall@google.com \
    --cc=dietmar.eggemann@arm.com \
    --cc=joshdon@google.com \
    --cc=juri.lelli@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mgorman@suse.de \
    --cc=mingo@redhat.com \
    --cc=olegrom@google.com \
    --cc=peterz@infradead.org \
    --cc=pjt@google.com \
    --cc=rientjes@google.com \
    --cc=rostedt@goodmis.org \
    --cc=steven.sistare@oracle.com \
    --cc=tj@kernel.org \
    --cc=vincent.guittot@linaro.org \
    --cc=viresh.kumar@linaro.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).