From: Oleg Nesterov <oleg@redhat.com>
To: David Rientjes <rientjes@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>,
Rik van Riel <riel@redhat.com>,
linux-mm@kvack.org
Subject: Re: [patch 2/2] oom: kill all threads sharing oom killed task's mm
Date: Mon, 16 Aug 2010 08:00:49 +0200 [thread overview]
Message-ID: <20100816060049.GB9498@redhat.com> (raw)
In-Reply-To: <alpine.DEB.2.00.1008151425271.8727@chino.kir.corp.google.com>
On 08/15, David Rientjes wrote:
>
> On Sun, 15 Aug 2010, Oleg Nesterov wrote:
>
> > Again, I do not know how the code looks without the patch, but
>
> Why not? This series is based on Linus' tree.
OK, thanks...
> > > + do_each_thread(g, q) {
> > > + if (q->mm == mm && !same_thread_group(q, p))
> > > + force_sig(SIGKILL, q);
> > > + } while_each_thread(g, q);
> >
> > We can kill the wrong task. "q->mm == mm" doesn't necessarily mean
> > we found the task which shares ->mm with p (see above).
> >
> > This needs atomic_inc(mm_users). And please do not use do_each_thread.
>
> Instead of using mm_users to pin the mm, we could simply do this iteration
> with for_each_process() before sending the SIGKILL to p.
Yes, this should work too. (I'd prefer to not take ->siglock under
task->alloc_lock, but currently this is correct and happens anyway).
Oleg.
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2010-08-16 6:03 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-08-15 4:30 [patch 1/2] oom: avoid killing a task if a thread sharing its mm cannot be killed David Rientjes
2010-08-15 4:31 ` [patch 2/2] oom: kill all threads sharing oom killed task's mm David Rientjes
2010-08-15 15:45 ` Oleg Nesterov
2010-08-15 21:28 ` David Rientjes
2010-08-16 6:00 ` Oleg Nesterov [this message]
2010-08-15 15:18 ` [patch 1/2] oom: avoid killing a task if a thread sharing its mm cannot be killed Oleg Nesterov
2010-08-15 21:23 ` David Rientjes
2010-08-16 5:52 ` Oleg Nesterov
2010-08-16 10:56 ` David Rientjes
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=20100816060049.GB9498@redhat.com \
--to=oleg@redhat.com \
--cc=akpm@linux-foundation.org \
--cc=kamezawa.hiroyu@jp.fujitsu.com \
--cc=kosaki.motohiro@jp.fujitsu.com \
--cc=linux-mm@kvack.org \
--cc=riel@redhat.com \
--cc=rientjes@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 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.