mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Tejun Heo <tj@kernel.org>
To: Usama Arif <usama.arif@linux.dev>
Cc: arighi@nvidia.com, bpf@vger.kernel.org, bsegall@google.com,
	changwoo@igalia.com, dietmar.eggemann@arm.com, etsal@meta.com,
	juri.lelli@redhat.com, kprateek.nayak@amd.com,
	linux-kernel@vger.kernel.org, mgorman@suse.de, mingo@redhat.com,
	peterz@infradead.org, rostedt@goodmis.org,
	sched-ext@lists.linux.dev, vincent.guittot@linaro.org,
	void@manifault.com, vschneid@redhat.com, yphbchou0911@gmail.com
Subject: Re: [PATCH] sched_ext: Place dsq_vtime next to dsq_priq
Date: Thu, 24 Sep 2026 06:57:56 -1000	[thread overview]
Message-ID: <6ae9d2d1972afdedf0117ec01aba783f@kernel.org> (raw)
In-Reply-To: <20260924161446.3039726-1-usama.arif@linux.dev>

Hello,

On Thu, Sep 24, 2026 at 09:14:46AM -0700, Usama Arif wrote:
> scx_dispatch_enqueue() calls rb_add() for a vtime-ordered DSQ while
> holding dsq->lock. At each level of the descent, scx_dsq_priq_less()
> loads the visited task's dsq_vtime, and that comparison selects rb_left
> or rb_right from the same task's dsq_priq. In the x86-64 benchmark
> configuration, these accesses fell on different 64-byte cache lines
> before this change, so a cold visited task could require a second cache
> line fill on the dependent descent path.

Applied to sched_ext/for-7.4.

Thanks.

--
tejun

      reply	other threads:[~2026-09-24 16:57 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-09-24 16:14 Usama Arif
2026-09-24 16:57 ` Tejun Heo [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=6ae9d2d1972afdedf0117ec01aba783f@kernel.org \
    --to=tj@kernel.org \
    --cc=arighi@nvidia.com \
    --cc=bpf@vger.kernel.org \
    --cc=bsegall@google.com \
    --cc=changwoo@igalia.com \
    --cc=dietmar.eggemann@arm.com \
    --cc=etsal@meta.com \
    --cc=juri.lelli@redhat.com \
    --cc=kprateek.nayak@amd.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mgorman@suse.de \
    --cc=mingo@redhat.com \
    --cc=peterz@infradead.org \
    --cc=rostedt@goodmis.org \
    --cc=sched-ext@lists.linux.dev \
    --cc=usama.arif@linux.dev \
    --cc=vincent.guittot@linaro.org \
    --cc=void@manifault.com \
    --cc=vschneid@redhat.com \
    --cc=yphbchou0911@gmail.com \
    /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
all inboxes | Powered by JetHome®