From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1031957Ab2COQyK (ORCPT ); Thu, 15 Mar 2012 12:54:10 -0400 Received: from mail-pz0-f52.google.com ([209.85.210.52]:63763 "EHLO mail-pz0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1031805Ab2COQyH (ORCPT ); Thu, 15 Mar 2012 12:54:07 -0400 Date: Thu, 15 Mar 2012 09:54:02 -0700 From: Tejun Heo To: Lennart Poettering Cc: Li Zefan , containers@lists.linux-foundation.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, Frederic Weisbecker Subject: Re: [PATCH] cgroup: deprecate remount option changes and "name=" mount option Message-ID: <20120315165402.GC32137@google.com> References: <20120314215228.GI7349@google.com> <20120314232925.GA16973@tango.0pointer.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120314232925.GA16973@tango.0pointer.de> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Thu, Mar 15, 2012 at 12:29:25AM +0100, Lennart Poettering wrote: > Hmm, this is not clear to me. Are you intending to remove the name= > mount option entirely, or just intend to remove that you can change it > in remounts? > > systemd uses name=systemd to get its own private cgroup tree, that has > no controller bound, hence we kinda need this option. Or are you > suggesting there was an other way to get a private cgroup tree that > systemd can use for grouping and labelling things? Eh, you're right. I want to remove support for duplicate mounting by name or subsys as it just isn't necessary, so what I want is, * "mount -t cgroupfs -o SUBSYS" will fail if SUBSYS is already mounted somewhere else. * "mount -t cgroupfs -o none" will always create a new cgroup hierarchy w/o any controller attached. I didn't realize that the mount code didn't allow none w/o name and now I don't see a non-intrusive way to remove the name option. :( Eh well, I'll drop that part. Thanks. -- tejun