All of lore.kernel.org
 help / color / mirror / Atom feed
From: Valentin Schneider <valentin.schneider@arm.com>
To: Dietmar Eggemann <dietmar.eggemann@arm.com>,
	linux-kernel@vger.kernel.org
Cc: Qais Yousef <qais.yousef@arm.com>,
	Lingutla Chandrasekhar <clingutla@codeaurora.org>,
	Peter Zijlstra <peterz@infradead.org>,
	Ingo Molnar <mingo@kernel.org>,
	Vincent Guittot <vincent.guittot@linaro.org>,
	Morten Rasmussen <morten.rasmussen@arm.com>,
	Quentin Perret <qperret@google.com>,
	Pavan Kondeti <pkondeti@codeaurora.org>,
	Rik van Riel <riel@surriel.com>
Subject: Re: [PATCH v4 3/3] sched/fair: Introduce a CPU capacity comparison helper
Date: Tue, 06 Apr 2021 16:59:26 +0100	[thread overview]
Message-ID: <87h7kjo141.mognet@arm.com> (raw)
In-Reply-To: <b03ae299-0b0c-3090-4d16-edbf2bdd5edb@arm.com>

On 06/04/21 17:37, Dietmar Eggemann wrote:
> On 01/04/2021 21:30, Valentin Schneider wrote:
>> While at it, replace group_smaller_{min, max}_cpu_capacity() with
>> comparisons of the source group's min/max capacity and the destination
>> CPU's capacity.
>
> IMHO, you haven't mentioned why you replace local sched group with dst
> CPU. I can see that only the capacity of the dst CPU makes really sense
> here. Might be worth mentioning in the patch header why. There is some
> of it in v3 6/7 but that's a different change.
>

Right, some of it got lost in the shuffling. This was a separate change in
v1 (4/8). I can reuse that changelog into:

"""
Also note that comparing capacity extrema of local and source sched_group's
doesn't make much sense when at the day of the day the imbalance will be
pulled by a known env->dst_cpu, whose capacity can be anywhere within the
local group's capacity extrema.

While at it, replace group_smaller_{min, max}_cpu_capacity() with
comparisons of the source group's min/max capacity and the destination
CPU's capacity.
"""

> Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
>
> [...]

      reply	other threads:[~2021-04-06 15:59 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-04-01 19:30 [PATCH v4 0/3] sched/fair: load-balance vs capacity margins Valentin Schneider
2021-04-01 19:30 ` [PATCH v4 1/3] sched/fair: Ignore percpu threads for imbalance pulls Valentin Schneider
2021-04-02 12:52   ` Vincent Guittot
2021-04-06 15:35   ` Dietmar Eggemann
2021-04-06 15:55     ` Valentin Schneider
2021-04-01 19:30 ` [PATCH v4 2/3] sched/fair: Clean up active balance nr_balance_failed trickery Valentin Schneider
2021-04-02 12:57   ` Vincent Guittot
2021-04-06 15:36   ` Dietmar Eggemann
2021-04-01 19:30 ` [PATCH v4 3/3] sched/fair: Introduce a CPU capacity comparison helper Valentin Schneider
2021-04-02 13:04   ` Vincent Guittot
2021-04-06 15:37   ` Dietmar Eggemann
2021-04-06 15:59     ` Valentin Schneider [this message]

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=87h7kjo141.mognet@arm.com \
    --to=valentin.schneider@arm.com \
    --cc=clingutla@codeaurora.org \
    --cc=dietmar.eggemann@arm.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@kernel.org \
    --cc=morten.rasmussen@arm.com \
    --cc=peterz@infradead.org \
    --cc=pkondeti@codeaurora.org \
    --cc=qais.yousef@arm.com \
    --cc=qperret@google.com \
    --cc=riel@surriel.com \
    --cc=vincent.guittot@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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.