From mboxrd@z Thu Jan 1 00:00:00 1970 From: Qais Yousef Subject: Re: [PATCH v9 3/8] cpuset: Rebuild root domain deadline accounting information Date: Sun, 15 Jan 2023 16:41:48 +0000 Message-ID: <20230115164148.lnoqfpg7em334ts3@airbuntu> References: <20190719140000.31694-1-juri.lelli@redhat.com> <20190719140000.31694-4-juri.lelli@redhat.com> <20221216233501.gh6m75e7s66dmjgo@airbuntu> <20221220114309.coi2o4ewosgouy6o@airbuntu> Mime-Version: 1.0 Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=layalina-io.20210112.gappssmtp.com; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=wyXeq2MEr1J+e0QY6nAt4hvGGGXhRFe/SJyt1uQjd+M=; b=HVKsp/vf0AVRuU856/IGt6skrRZgxXhP5I4Y/qoLNwpTmzYThPiVRxsVlvJJmA2Hg8 tV7IHYq1EnC+YIpW7nqTWWsd259d0i6s++jbssfomjbxGF0jqnK5YIE9DH/SkAO3JLxM uS3s6sDNNElol4/q/sxBwK4HKwEwolb4mt0ZDnNTvQYzoD6hXCHFYV8wQWFiWwjYg7Rl uoYg9AkFXmyKNC4d7x4HjFxlkLF43etPXh1w5UD9EU9MiBBJ1CV7f6PikjHHNpIaCbMk Hgh+DGvyf19Jvt03Vhtv6xgnvLiGGsToOPXr97ilY6D6nQjhYAwKouUCVxcIeq3VXDwf A3bA== Content-Disposition: inline In-Reply-To: <20221220114309.coi2o4ewosgouy6o@airbuntu> List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Vincent Guittot Cc: Juri Lelli , peterz-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org, mingo-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, rostedt-nx8X9YLhiw1AfugRpC6u6w@public.gmane.org, tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, luca.abeni-5rdYK369eBLQB0XuIGIEkQ@public.gmane.org, claudio-YOzL5CV4y4YG1A2ADO40+w@public.gmane.org, tommaso.cucinotta-5rdYK369eBLQB0XuIGIEkQ@public.gmane.org, bristot-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, mathieu.poirier-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org, longman-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, dietmar.eggemann-5wv7dgnIgG8@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Wei Wang , Rick Yiu , Quentin Perret On 12/20/22 11:43, Qais Yousef wrote: > On 12/19/22 09:07, Vincent Guittot wrote: > > On Sat, 17 Dec 2022 at 00:35, Qais Yousef wrote: > > > > > > Hi > > > > > > On 07/19/19 15:59, Juri Lelli wrote: > > > > When the topology of root domains is modified by CPUset or CPUhotplug > > > > operations information about the current deadline bandwidth held in the > > > > root domain is lost. > > > > > > > > This patch addresses the issue by recalculating the lost deadline > > > > bandwidth information by circling through the deadline tasks held in > > > > CPUsets and adding their current load to the root domain they are > > > > associated with. > > > > > > > > Signed-off-by: Mathieu Poirier > > > > Signed-off-by: Juri Lelli > > > > --- > > > > > > We see that rebuild_root_domain() can take 10+ ms (I get a max of 20ms quite > > > consistently) on suspend/resume. > > > > > > Do we actually need to rebuild_root_domain() if we're going through > > > a suspend/resume cycle? > > > > During suspend to ram, there are cpus hotplug operation but If you use > > suspend to idle, you will skip cpus hotplug operation and its > > associated rebuild. > > Thanks Vincent. I'll check on that - but if we want to keep suspend to ram? > Do we really to incur this hit? Using s2idle is not an option actually. I'll prepare v2 to address Waiman comment if I don't get more feedback in the next few days. Thanks!