linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Tejun Heo <tj@kernel.org>
To: Colin Cross <ccross@android.com>
Cc: "Linux PM list" <linux-pm@vger.kernel.org>,
	lkml <linux-kernel@vger.kernel.org>,
	"Rafael J. Wysocki" <rjw@sisk.pl>,
	"Arve Hjønnevåg" <arve@android.com>,
	"Li Zefan" <lizefan@huawei.com>,
	"Len Brown" <len.brown@intel.com>, "Pavel Machek" <pavel@ucw.cz>,
	containers@lists.linux-foundation.org, cgroups@vger.kernel.org
Subject: Re: [PATCH 02/10] freezer: skip waking up tasks with PF_FREEZER_SKIP set
Date: Mon, 29 Apr 2013 15:08:31 -0700	[thread overview]
Message-ID: <20130429220831.GC2395@htj.dyndns.org> (raw)
In-Reply-To: <CAMbhsRQHkm=XTYtummEZq1h4sa-tRGwLpk8Uyhpj9D3+jQF3dg@mail.gmail.com>

Hey,

On Mon, Apr 29, 2013 at 03:02:19PM -0700, Colin Cross wrote:
> See the first patch in the series (which isn't available in the
> archive yet, so I can't link to it).  The short version is that

It didn't arrive in my lkml folder either.  Maybe vger is taking some
time distributing emails.

> Android goes through suspend/resume very often (every few seconds when
> on a busy wifi network with the screen off), and a significant portion
> of the energy used to go in and out of suspend is spent in the
> freezer.  This patch series takes the most common userspace sleep
> points and converts them to PF_FREEZER_SKIP, which reduces the number
> of context switches for every suspend or resume event on a
> freshly-booted Android device from 1000 to 25, and reduces the time

Ah, okay, so you're spreading PF_FREEZER_SKIP.  When you post patches
which touch the freezer can you please cc me and Oleg Nesterov
<oleg@redhat.com> (I'll ping him this time)?  Freezer has been very
subtly broken in various ways and many kthread users are still broken,
so let's tread carefully.

> spent freezing by a factor of 5.  It will have a similar effect on a
> non-Android system, although those generally don't care about
> suspend/resume optimization.

Yeah, if it's something which makes actual difference rather than
"this seems to be a good idea" thing, sure, let's find a way.

Thanks.

-- 
tejun

  reply	other threads:[~2013-04-29 22:08 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-04-29 21:45 [PATCH 00/10] optimize freezing tasks by reducing task wakeups Colin Cross
2013-04-29 21:45 ` [PATCH 01/10] freezer: shorten freezer sleep time using exponential backoff Colin Cross
2013-05-02 12:28   ` Pavel Machek
2013-04-29 21:45 ` [PATCH 02/10] freezer: skip waking up tasks with PF_FREEZER_SKIP set Colin Cross
2013-04-29 21:51   ` Tejun Heo
2013-04-29 21:57     ` Tejun Heo
2013-04-29 22:02       ` Colin Cross
2013-04-29 22:08         ` Tejun Heo [this message]
2013-04-29 22:16           ` Tejun Heo
2013-04-30 11:48             ` Rafael J. Wysocki
2013-04-30 17:10   ` Oleg Nesterov
2013-04-30 17:15     ` Oleg Nesterov
2013-04-29 21:45 ` [PATCH 03/10] freezer: add new freezable helpers using freezer_do_not_count() Colin Cross
2013-05-02 12:48   ` Pavel Machek
2013-05-02 13:05     ` Oliver Neukum
2013-05-02 13:46       ` Pavel Machek
2013-05-02 17:05     ` Colin Cross
2013-05-03 14:00       ` Pavel Machek
2013-04-29 21:45 ` [PATCH 04/10] binder: use freezable blocking calls Colin Cross
2013-04-29 21:45 ` [PATCH 05/10] epoll: use freezable blocking call Colin Cross
2013-04-29 21:45 ` [PATCH 06/10] select: " Colin Cross
2013-04-29 21:45 ` [PATCH 07/10] futex: " Colin Cross
2013-04-29 22:52   ` Darren Hart
2013-04-29 23:46     ` Colin Cross
2013-05-02 19:52     ` Matt Helsley
2013-04-29 21:45 ` [PATCH 08/10] nanosleep: " Colin Cross
2013-04-29 21:45 ` [PATCH 09/10] sigtimedwait: " Colin Cross
2013-04-30 16:38   ` Oleg Nesterov
2013-04-30 16:56     ` Oleg Nesterov
2013-04-30 16:58     ` Colin Cross
2013-04-30 17:00       ` Oleg Nesterov
2013-04-29 21:45 ` [PATCH 10/10] af_unix: use freezable blocking calls in read Colin Cross

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=20130429220831.GC2395@htj.dyndns.org \
    --to=tj@kernel.org \
    --cc=arve@android.com \
    --cc=ccross@android.com \
    --cc=cgroups@vger.kernel.org \
    --cc=containers@lists.linux-foundation.org \
    --cc=len.brown@intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pm@vger.kernel.org \
    --cc=lizefan@huawei.com \
    --cc=pavel@ucw.cz \
    --cc=rjw@sisk.pl \
    /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).