From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751973AbZJVP4u (ORCPT ); Thu, 22 Oct 2009 11:56:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751815AbZJVP4t (ORCPT ); Thu, 22 Oct 2009 11:56:49 -0400 Received: from e7.ny.us.ibm.com ([32.97.182.137]:44430 "EHLO e7.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751890AbZJVP4s (ORCPT ); Thu, 22 Oct 2009 11:56:48 -0400 Subject: Re: [PATCH 3/5 v4] Export memory_sysdev_class From: Dave Hansen To: Nathan Fontenot Cc: linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org In-Reply-To: <4AE07AB7.2070901@austin.ibm.com> References: <4ADF1C49.2030201@austin.ibm.com> <4ADF1E42.3020907@austin.ibm.com> <1256141009.23737.22.camel@nimitz> <4AE07AB7.2070901@austin.ibm.com> Content-Type: text/plain Date: Thu, 22 Oct 2009 08:56:46 -0700 Message-Id: <1256227006.23737.784.camel@nimitz> Mime-Version: 1.0 X-Mailer: Evolution 2.26.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2009-10-22 at 10:31 -0500, Nathan Fontenot wrote: > Dave Hansen wrote: > > On Wed, 2009-10-21 at 09:44 -0500, Nathan Fontenot wrote: > >> Export the memory_sysdev_class structure. This is needed so we can create > >> a 'release' file in sysfs in addition to the existing 'probe' file in > >> order to support DLPAR removal of memory on the powerpc/pseries platform. > >> The new 'release' file will be powerpc/pseries only. > > > > Please do it in generic code. You may only need it on ppc today, but > > somebody else is going to want the same thing tomorrow on another arch. > > I thought about this but wasn't sure if having the probe/release sysfs files > for memory and cpu be in generic code would be accepted. Although we don't want to pollute the generic code with lots of per-arch cruft, this still looks pretty generic to me. It is also really nice to have all of the sysfs files for one directory be in a single place in the source. > Would it be acceptable to put the new release file for memory under the > ARCH_MEMORY_PROBE config option? That sounds fine to me. It may need a slightly tuned name if you can think of anything better. I can't off the top of my head. x86's is really only there for testing reasons. I would use mem= to shrink a machine's memory at boot then use the probe file to re-add it later. I did that before I had hardware that could do real hotplug. > This would reduce the number of arch'es > that would require stubs as it appears only powerpc and x86 define this. Yeah, that'd be a nice side-effect I guess. -- Dave