Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755730Ab2F1SaG (ORCPT ); Thu, 28 Jun 2012 14:30:06 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:49069 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751275Ab2F1SaE (ORCPT ); Thu, 28 Jun 2012 14:30:04 -0400 Date: Thu, 28 Jun 2012 11:29:34 -0700 From: Tejun Heo To: Michal Hocko Cc: David Rientjes , Zhouping Liu , linux-mm@kvack.org, Li Zefan , CAI Qian , LKML , Andrew Morton , KAMEZAWA Hiroyuki , aneesh.kumar@linux.vnet.ibm.com Subject: Re: memcg: cat: memory.memsw.* : Operation not supported Message-ID: <20120628182934.GD22641@google.com> References: <2a1a74bf-fbb5-4a6e-b958-44fff8debff2@zmail13.collab.prod.int.phx2.redhat.com> <34bb8049-8007-496c-8ffb-11118c587124@zmail13.collab.prod.int.phx2.redhat.com> <20120627154827.GA4420@tiehlicka.suse.cz> <20120628123611.GA16042@tiehlicka.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120628123611.GA16042@tiehlicka.suse.cz> 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 Content-Length: 1371 Lines: 36 Hello, Michal. On Thu, Jun 28, 2012 at 02:36:11PM +0200, Michal Hocko wrote: > @@ -2726,6 +2726,9 @@ static int cgroup_addrm_files(struct cgroup *cgrp, struct cgroup_subsys *subsys, > int err, ret = 0; > > for (cft = cfts; cft->name[0] != '\0'; cft++) { > + if (subsys->cftype_enabled && !subsys->cftype_enabled(cft->name)) > + continue; > + > if (is_add) > err = cgroup_add_file(cgrp, subsys, cft); > else I hope we could avoid this dynamic decision. That was one of the main reasons behind doing the cftype thing. It's better to be able to "declare" these kind of things rather than being able to implement fully flexible dynamic logic. Too much flexibility often doesn't achieve much while being a hindrance to evolution of code base (trying to improve / simplify X - ooh... there's this single wacko corner case YYY here which is really different from all other users). really_do_swap_account can't change once booted, right? Why not just separate out memsw cfts into a separate array and call cgroup_add_cftypes() from init path? Can't we do that from enable_swap_cgroup()? Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/