linux-pm.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Pavel Machek <pavel@ucw.cz>
To: Len Brown <lenb@kernel.org>
Cc: rjw@rjwysocki.net, linux-pm@vger.kernel.org,
	linux-kernel@vger.kernel.org, Len Brown <len.brown@intel.com>
Subject: Re: [PATCH 1/1] suspend: make sync() on suspend-to-RAM optional
Date: Wed, 15 Jul 2015 08:43:21 +0200	[thread overview]
Message-ID: <20150715064320.GA23713@amd> (raw)
In-Reply-To: <505338dbbcdce9416ac05f67288b10442fbda179.1436926113.git.len.brown@intel.com>

On Tue 2015-07-14 22:24:51, Len Brown wrote:
> From: Len Brown <len.brown@intel.com>
> 
> The Linux kernel suspend path has traditionally invoked sys_sync().
> 
> But sys_sync() can be expensive, and some systems do not want
> to pay the cost of sys_sync() on every suspend.

Have you measured how expesive it can be, and why it is expensive?

> So make sys_sync on suspend optional.
> 
> Create sysfs attribute /sys/power/pm_suspend_do_sync.
> When set to 1, the kernel will sys_sync() on suspend,
> When set to 0, it will not.
> 
> This attribute can be changed by root at run-time.
> Kernel build parameter CONFIG_PM_SUSPEND_DO_SYNC_DEFAULT.
> As this is 1, by default, this patch does not change
> default behavior.

Why do you need CONFIG parameter?


									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

  reply	other threads:[~2015-07-15  6:43 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-07-15  2:24 [PATCH v4 0/1] suspend: make sync() on suspend-to-RAM optional Len Brown
2015-07-15  2:24 ` [PATCH 1/1] " Len Brown
2015-07-15  6:43   ` Pavel Machek [this message]
2015-07-15 14:06     ` Austin S Hemmelgarn
2015-07-15 14:58       ` Brown, Len
2015-07-17 23:54         ` Rafael J. Wysocki
2015-07-21  9:38           ` Pavel Machek
2015-07-21 14:41             ` Rafael J. Wysocki
2015-07-21 15:19               ` Pavel Machek
2015-07-21 15:36                 ` Austin S Hemmelgarn
2015-07-21 20:11                   ` Pavel Machek
2015-07-21 20:01                 ` Brown, Len
2015-07-21 20:05                   ` Pavel Machek
2015-07-22  1:25                 ` Rafael J. Wysocki
2015-07-22  7:23                   ` Pavel Machek
2015-07-22  8:55                   ` Oliver Neukum
2015-07-31 16:02                     ` Len Brown
2015-07-31 23:56                       ` Rafael J. Wysocki
2015-10-08 15:50                         ` Pavel Machek
  -- strict thread matches above, loose matches on Subject: below --
2014-01-23  7:11 Len Brown
2014-01-23  7:29 ` Zhang Rui
2014-01-23  7:41   ` Brown, Len
2014-01-23  7:38 ` Srivatsa S. Bhat
2014-01-23  7:59   ` Brown, Len
2014-01-26 21:08 ` Pavel Machek
2015-05-08  6:41   ` Len Brown

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=20150715064320.GA23713@amd \
    --to=pavel@ucw.cz \
    --cc=len.brown@intel.com \
    --cc=lenb@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pm@vger.kernel.org \
    --cc=rjw@rjwysocki.net \
    /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).