From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753751Ab1IBRbg (ORCPT ); Fri, 2 Sep 2011 13:31:36 -0400 Received: from mail-gx0-f174.google.com ([209.85.161.174]:56678 "EHLO mail-gx0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753607Ab1IBRbf (ORCPT ); Fri, 2 Sep 2011 13:31:35 -0400 Date: Sat, 3 Sep 2011 02:31:27 +0900 From: Tejun Heo To: Oleg Nesterov Cc: Matt Helsley , "Rafael J. Wysocki" , Paul Menage , containers@lists.linux-foundation.org, linux-pm@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH pm-freezer 1/4] cgroup_freezer: fix freezer->state setting bug in freezer_change_state() Message-ID: <20110902173127.GA3083@htj.dyndns.org> References: <20110831102100.GA2828@mtj.dyndns.org> <20110902004231.GF1919@count0.beaverton.ibm.com> <20110902165839.GA7478@redhat.com> <20110902170844.GJ2752@htj.dyndns.org> <20110902171517.GA8247@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110902171517.GA8247@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Fri, Sep 02, 2011 at 07:15:17PM +0200, Oleg Nesterov wrote: > > I guess it depends on the viewpoint. A simple analogy would be using > > WARN_ON_ONCE() instead of BUG_ON() so that the mode of failure is > > softer. This change isn't likely to make bugs significantly more > > difficult to discover so why not? > > I agree either way. > > Personally I prefer your current patch. Because it is not clear why > do we call try_to_freeze_cgroup() if it was already called. And, the > 2nd call can silently hide the problem if we have some bug. > > But of course, this is up to you and Matt. I'm okay either way too. It would make a bug in that area a bit less annoying and thus may decrease the chance of bug report, but it means that we ship with built-in easy work around (if it doesn't work at the first kick, kick again), which can be beneficial in practice. > > > But I agree either way. Rafael, I think 1-4 are fine, but I think > > > we need the simple 5/4, will send in a minute... > > > > Can you please wait a bit? The second one was broken (missing unlock) > > Yes, I just noticed the small problem too, hopefully we mean the same > bug ;) Yeap, the same one. I thought it was the second patch instead of the third. :) Thanks. -- tejun