linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Anton Vorontsov <anton.vorontsov@linaro.org>
To: Oleg Nesterov <oleg@redhat.com>
Cc: "Arve Hjønnevåg" <arve@android.com>,
	"KOSAKI Motohiro" <kosaki.motohiro@gmail.com>,
	"Greg Kroah-Hartman" <gregkh@suse.de>,
	"San Mehat" <san@google.com>, "Colin Cross" <ccross@android.com>,
	"Eric W. Biederman" <ebiederm@xmission.com>,
	linux-kernel@vger.kernel.org, kernel-team@android.com,
	linaro-kernel@lists.linaro.org
Subject: Re: [PATCH 1/3] procfs: Export next_tgid(), move it to kernel/pid.c
Date: Tue, 31 Jan 2012 00:49:20 +0400	[thread overview]
Message-ID: <20120130204920.GA27812@oksana.dev.rtsoft.ru> (raw)
In-Reply-To: <20120130134312.GA14110@redhat.com>

On Mon, Jan 30, 2012 at 02:43:12PM +0100, Oleg Nesterov wrote:
> On 01/30, Anton Vorontsov wrote:
> >
> > We'd like to use this function in the android low memory killer driver, so
> > let's export it.
> 
> I guess you mean 3/3.
> 
> If lowmem_shrink() can use next_tid() which is not really accurate,
> then why tou can't simply change it to use rcu_read_lock ?

Yes, in LMK driver we don't need to be accurate. I probably could use
rcu_read_lock, but the plan was in not holding any global locks (in
this case the rcu) at all, instead I'd like to hold just a reference
of the task, which the driver is analyzing at this time. Once we decide
(to kill or not to kill the task), we either send a signal (and drop
the reference) or just drop the reference.

Thanks,

-- 
Anton Vorontsov
Email: cbouatmailru@gmail.com

  reply	other threads:[~2012-01-30 20:49 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-01-30  1:13 [PATCH 1/3] procfs: Export next_tgid(), move it to kernel/pid.c Anton Vorontsov
2012-01-30  2:22 ` Greg KH
2012-01-30 19:50   ` Anton Vorontsov
2012-01-30  3:26 ` Eric W. Biederman
2012-01-30 19:51   ` Anton Vorontsov
2012-01-30 13:43 ` Oleg Nesterov
2012-01-30 20:49   ` Anton Vorontsov [this message]
2012-01-31  1:51     ` Eric W. Biederman
2012-02-01  4:19       ` Anton Vorontsov
2012-02-01  4:37         ` Eric W. Biederman

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=20120130204920.GA27812@oksana.dev.rtsoft.ru \
    --to=anton.vorontsov@linaro.org \
    --cc=arve@android.com \
    --cc=ccross@android.com \
    --cc=ebiederm@xmission.com \
    --cc=gregkh@suse.de \
    --cc=kernel-team@android.com \
    --cc=kosaki.motohiro@gmail.com \
    --cc=linaro-kernel@lists.linaro.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=oleg@redhat.com \
    --cc=san@google.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;
as well as URLs for NNTP newsgroup(s).