From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: Re: [RFC] Prefixing cgroup generic control filenames with "cgroup." Date: Thu, 28 Feb 2008 13:21:42 -0800 Message-ID: <20080228132142.4d4b1eef.akpm@linux-foundation.org> References: <6599ad830802281314s25c033d6tc021725ae28aef8d@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <6599ad830802281314s25c033d6tc021725ae28aef8d-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Paul Menage Cc: a.p.zijlstra-/NLkJaSkS4VmR6Xm/wNWPw@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, containers-qjLDD68F18O7TbgM5vRIOg@public.gmane.org, balbir-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org, xemul-GEFAQzZX7r8dnm+yROfE0A@public.gmane.org List-Id: containers.vger.kernel.org On Thu, 28 Feb 2008 13:14:05 -0800 "Paul Menage" wrote: > All control files created by cgroup subsystems are given a prefix > corresponding to their subsystem name. But control files provided by > cgroups itself have no prefix. Currently that set of files is just > "tasks", "notify_on_release" and "release_agent", but that set is > likely to expand in the future. To reduce the risk of clashes, it > would make sense to prefix these files and any future ones with the > "cgroup." prefix. > > The only reason that I can see *not* to do this would be for > compatibility with 2.6.24. Do people think this is a strong enough > reason to leave the existing names? If distros are planning to ship > products based on 2.6.24, presumably they'd be adding their own > patches anyway, so they could add a trivial prefix change patch too. > (I realise this discussion would have been more useful *before* 2.6.24 > shipped, but I didn't quite get round to it ...) > > A compromise might be to keep "tasks" unprefixed, and say that future > names get the "cgroup." prefix; in this case I'd be inclined to add > the prefix to notify_on_release and release_agent on the grounds that > there's much less chance of breaking anyone with those files since (I > suspect) they're much less used. > > Note that if you mount a cgroup filesystem with the "noprefix" option, > which is what the cpuset filesystem wrapper does, no subsystems have > prefixes, and in this case the "cgroup." prefix wouldn't be used > either. So this doesn't affect any users that explicitly mount cpusets > rather than cgroups. > > Thoughts? > It would be easier to judge if we could see the full directory tree. Because if something is in /foo/bar/cgroup/notify_on_release then prefixing the filename with "cgroup_" seems pretty pointless.