From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758031AbYDCXtp (ORCPT ); Thu, 3 Apr 2008 19:49:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753530AbYDCXti (ORCPT ); Thu, 3 Apr 2008 19:49:38 -0400 Received: from smtp-out.google.com ([216.239.33.17]:23301 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750770AbYDCXth (ORCPT ); Thu, 3 Apr 2008 19:49:37 -0400 DomainKey-Signature: a=rsa-sha1; s=beta; d=google.com; c=nofws; q=dns; h=received:message-id:date:from:to:subject:cc:in-reply-to: mime-version:content-type:content-transfer-encoding: content-disposition:references; b=C0aKp7ynF94i/Sk1Ydex/wxoHpjgZ2pwLeoDuPkfSmZRNcmGNArMeoPJXzL3AOssp S14G+Gc3lnA5+UPQcqLBA== Message-ID: <6599ad830804031649p6bbc60f3s59fb7c25a7260505@mail.gmail.com> Date: Thu, 3 Apr 2008 16:49:24 -0700 From: "Paul Menage" To: matthltc@us.ibm.com Subject: Re: [Devel] [RFC PATCH 0/4] Container Freezer: Reuse Suspend Freezer Cc: Linux-Kernel , "Linux Containers" In-Reply-To: <20080403210316.397506379@us.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20080403210316.397506379@us.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Apr 3, 2008 at 2:03 PM, wrote: > > * "freezer.kill" > > writing will send signal number to all tasks > My first thought (not having looked at the code yet) is that sending a signal doesn't really have anything to do with freezing, so it shouldn't be in the same subsystem. Maybe a separate subsystem called "signal"? And more than that, it's not something that requires any particular per-process state, so there's no reason that the subsystem that provides the "kill" functionality shouldn't be able to be mounted in multiple hierarchies. How about if I added support for stateless subsystems, that could potentially be mounted in multiple hierarchies at once? They wouldn't need an entry in the css set, since they have no state. > * Usage : > > # mkdir /containers/freezer > # mount -t container -ofreezer freezer /containers/freezer > # mkdir /containers/freezer/0 > # echo $some_pid > /containers/freezer/0/tasks > > to get status of the freezer subsystem : > > # cat /containers/freezer/0/freezer.freeze > RUNNING > > to freeze all tasks in the container : > > # echo 1 > /containers/freezer/0/freezer.freeze > # cat /containers/freezer/0/freezer.freeze > FREEZING > # cat /containers/freezer/0/freezer.freeze > FROZEN Could we separate this out into two files? One called "freeze" that's a 0/1 for whether we're intending to freeze the subsystem, and one called "frozen" that indicates whether it is frozen? And maybe a "state" file to report the RUNNING/FREEZING/FROZEN distinction in a human-readable way? Paul