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Message-ID: <b0bc6ad6c485117731f715a00992c0e414ba8b85.camel@suse.com>
Subject: Re: [RFC PATCH v4 00/19] Core scheduling v4
From:   Dario Faggioli <dfaggioli@suse.com>
To:     Greg Kerr <kerrnel@chromium.org>,
        Vineeth Remanan Pillai <vpillai@digitalocean.com>
Cc:     Phil Auld <pauld@redhat.com>,
        Nishanth Aravamudan <naravamudan@digitalocean.com>,
        Julien Desfossez <jdesfossez@digitalocean.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Tim Chen <tim.c.chen@linux.intel.com>,
        Ingo Molnar <mingo@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Paul Turner <pjt@google.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Linux List Kernel Mailing <linux-kernel@vger.kernel.org>,
        =?ISO-8859-1?Q?Fr=E9d=E9ric?= Weisbecker <fweisbec@gmail.com>,
        Kees Cook <keescook@chromium.org>,
        Aaron Lu <aaron.lwe@gmail.com>,
        Aubrey Li <aubrey.intel@gmail.com>,
        Valentin Schneider <valentin.schneider@arm.com>,
        Mel Gorman <mgorman@techsingularity.net>,
        Pawan Gupta <pawan.kumar.gupta@linux.intel.com>,
        Paolo Bonzini <pbonzini@redhat.com>
Date:   Fri, 01 Nov 2019 19:07:59 +0100
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References: <cover.1572437285.git.vpillai@digitalocean.com>
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         <CANaguZCqHnR8b_68SSA_rfdkinVg8vLH66jQ_GhMsdOjuUHe3g@mail.gmail.com>
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On Fri, 2019-11-01 at 09:35 -0700, Greg Kerr wrote:
> Has anyone considering shipping a V1 implementation which just allows
> threads from the same process to share a core together? And then
> iterating on that? Would that be simpler to implement or do the same
> fundamental problems exist as tagging arbitrary processes with
> cookies?
>=20
IMO, the latter, i.e., the same fundamental problem exist.

It's _tasks_ having to be scheduled in a certain way.

It does not matter much, as far as the necessary modifications to the
scheduler are concerned, whether those tasks are independent processes,
or threads or the same process, or vcpus of a VMs, etc...

Regards
--=20
Dario Faggioli, Ph.D
http://about.me/dario.faggioli
Virtualization Software Engineer
SUSE Labs, SUSE https://www.suse.com/
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