From: Andrew Morton <akpm@linux-foundation.org>
To: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: linux-kernel@vger.kernel.org,
Pavel Emelyanov <xemul@parallels.com>,
Serge Hallyn <serge.hallyn@canonical.com>,
KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
Kees Cook <keescook@chromium.org>, Tejun Heo <tj@kernel.org>,
Andrew Vagin <avagin@openvz.org>,
"Eric W. Biederman" <ebiederm@xmission.com>,
Alexey Dobriyan <adobriyan@gmail.com>
Subject: Re: [patch 1/4] fs, proc: Introduce /proc/<pid>/task/<tid>/children entry v8
Date: Tue, 24 Jan 2012 15:53:03 -0800 [thread overview]
Message-ID: <20120124155303.acbb3b11.akpm@linux-foundation.org> (raw)
In-Reply-To: <20120123142436.181674896@openvz.org>
On Mon, 23 Jan 2012 18:20:37 +0400
Cyrill Gorcunov <gorcunov@openvz.org> wrote:
> When we do checkpoint of a task we need to know the list of children
> the task, has but there is no easy and fast way to generate reverse
> parent->children chain from arbitrary <pid> (while a parent pid is
> provided in "PPid" field of /proc/<pid>/status).
>
> So instead of walking over all pids in the system (creating one big process
> tree in memory, just to figure out which children a task has) -- we add
> explicit /proc/<pid>/task/<tid>/children entry, because the kernel already has
> this kind of information but it is not yet exported.
>
> This is a first level children, not the whole process tree.
Is there a reason for not putting this new code inside
CONFIG_CHECKPOINT_RESTART? If so, please changelog that.
We could add
/* #ifdef CONFIG_CHECKPOINT_RESTART (reasoning goes here) */
so that if we should decide to pull all this code out again, a grep
will flag this code for consideration.
next prev parent reply other threads:[~2012-01-24 23:53 UTC|newest]
Thread overview: 60+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-01-23 14:20 [patch 0/4] A few patches in a sake of c/r functionality Cyrill Gorcunov
2012-01-23 14:20 ` [patch 1/4] fs, proc: Introduce /proc/<pid>/task/<tid>/children entry v8 Cyrill Gorcunov
2012-01-23 18:54 ` Kees Cook
2012-01-23 19:33 ` Cyrill Gorcunov
2012-01-23 20:29 ` Kees Cook
2012-01-23 20:39 ` Cyrill Gorcunov
2012-01-24 2:07 ` KAMEZAWA Hiroyuki
2012-01-24 6:53 ` Cyrill Gorcunov
2012-01-24 7:07 ` KAMEZAWA Hiroyuki
2012-01-24 7:21 ` Cyrill Gorcunov
2012-01-24 8:52 ` Eric W. Biederman
2012-01-24 9:11 ` Cyrill Gorcunov
2012-01-25 1:14 ` KOSAKI Motohiro
2012-01-25 2:11 ` Eric W. Biederman
2012-01-25 6:55 ` Cyrill Gorcunov
2012-01-25 15:29 ` Cyrill Gorcunov
2012-01-24 8:51 ` Cyrill Gorcunov
2012-01-24 23:53 ` Andrew Morton [this message]
2012-01-25 6:52 ` Cyrill Gorcunov
2012-01-23 14:20 ` [patch 2/4] [RFC] syscalls, x86: Add __NR_kcmp syscall v4 Cyrill Gorcunov
2012-01-23 18:48 ` H. Peter Anvin
2012-01-23 20:03 ` Cyrill Gorcunov
2012-01-24 2:16 ` KAMEZAWA Hiroyuki
2012-01-24 6:47 ` Cyrill Gorcunov
2012-01-24 7:04 ` H. Peter Anvin
2012-01-24 7:17 ` Cyrill Gorcunov
2012-01-24 7:20 ` KAMEZAWA Hiroyuki
2012-01-24 7:38 ` Cyrill Gorcunov
2012-01-24 7:40 ` KAMEZAWA Hiroyuki
2012-01-24 8:48 ` Cyrill Gorcunov
2012-01-24 20:20 ` KOSAKI Motohiro
2012-01-24 20:26 ` Cyrill Gorcunov
2012-01-24 20:44 ` Eric W. Biederman
2012-01-24 20:50 ` Cyrill Gorcunov
2012-01-24 21:20 ` Eric W. Biederman
2012-01-24 21:34 ` Cyrill Gorcunov
2012-01-24 21:22 ` Andrew Morton
2012-01-24 21:45 ` Andrew Morton
2012-01-24 21:46 ` H. Peter Anvin
2012-01-24 22:00 ` Andrew Morton
2012-01-24 22:52 ` H. Peter Anvin
2012-01-24 23:42 ` Andrew Morton
2012-01-24 21:46 ` Cyrill Gorcunov
2012-01-24 21:59 ` Andrew Morton
2012-01-24 22:54 ` Eric W. Biederman
2012-01-24 22:54 ` Andrew Morton
2012-01-24 21:25 ` Andrew Morton
2012-01-24 21:31 ` Cyrill Gorcunov
2012-01-24 8:49 ` Eric W. Biederman
2012-01-24 8:49 ` Cyrill Gorcunov
2012-01-23 14:20 ` [patch 3/4] c/r: procfs: add arg_start/end, env_start/end and exit_code members to /proc/$pid/stat Cyrill Gorcunov
2012-01-23 20:42 ` Kees Cook
2012-01-23 20:53 ` Cyrill Gorcunov
2012-01-24 23:59 ` Andrew Morton
2012-01-25 6:54 ` Cyrill Gorcunov
2012-01-25 7:12 ` Andrew Morton
2012-01-25 7:18 ` Cyrill Gorcunov
2012-01-23 14:20 ` [patch 4/4] c/r: prctl: Extend PR_SET_MM to set up more mm_struct entries Cyrill Gorcunov
2012-01-23 15:55 ` Cyrill Gorcunov
2012-01-23 20:02 ` Cyrill Gorcunov
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=20120124155303.acbb3b11.akpm@linux-foundation.org \
--to=akpm@linux-foundation.org \
--cc=adobriyan@gmail.com \
--cc=avagin@openvz.org \
--cc=ebiederm@xmission.com \
--cc=gorcunov@openvz.org \
--cc=kamezawa.hiroyu@jp.fujitsu.com \
--cc=keescook@chromium.org \
--cc=linux-kernel@vger.kernel.org \
--cc=serge.hallyn@canonical.com \
--cc=tj@kernel.org \
--cc=xemul@parallels.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.