Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755608Ab2BGHwD (ORCPT ); Tue, 7 Feb 2012 02:52:03 -0500 Received: from nat28.tlf.novell.com ([130.57.49.28]:30962 "EHLO nat28.tlf.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754189Ab2BGHwB convert rfc822-to-8bit (ORCPT ); Tue, 7 Feb 2012 02:52:01 -0500 Message-Id: <4F30E62B02000078000717EB@nat28.tlf.novell.com> X-Mailer: Novell GroupWise Internet Agent 12.0.0 Date: Tue, 07 Feb 2012 07:51:55 +0000 From: "Jan Beulich" To: "Konrad Rzeszutek Wilk" Cc: "Jeremy Fitzhardinge" , , "Dan Magenheimer" , Subject: Re: [PATCH] xen/tmem: cleanup References: <4F2C06A00200007800071071@nat28.tlf.novell.com> <4F2F998202000078000714CD@nat28.tlf.novell.com> <4F3012B602000078000716AB@nat28.tlf.novell.com> <20120206170224.GD23240@phenom.dumpdata.com> In-Reply-To: <20120206170224.GD23240@phenom.dumpdata.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8BIT Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1975 Lines: 42 >>> On 06.02.12 at 18:02, Konrad Rzeszutek Wilk wrote: > On Mon, Feb 06, 2012 at 04:49:42PM +0000, Jan Beulich wrote: >> >>> On 06.02.12 at 17:37, Dan Magenheimer wrote: >> >> From: Jan Beulich [mailto:JBeulich@suse.com] >> >> > tmem_enabled is used in xen/drivers/xen-selfballoon.c >> >> >> >> Which can't be built as a module, and hence the symbol doesn't need >> >> exporting. This patch (of course, I'm tempted to say) survived build >> >> testing. >> > >> > Yes, correct. BUT... I think only the reason xen-selfballoon.c >> > can't be built as a module is because the MM variable vm_committed_as >> > (or an access function) is not exported. Ideally xen-selfballoon.c >> > probably should be a module but putting a core MM change in >> > the critical path of a Xen-only-related enhancement seemed >> > a recipe for sure failure. >> >> No, this isn't the main reason (as you say further down, this could >> easily be adjusted for) afaict. The main reason is that >> register_xen_selfballooning() is being called from non-modular >> code (xen-balloon.c), which could be made a module too, but in >> turn has at least one reference that wouldn't be nice to become >> an export (balloon_set_new_target()). > > It would be nice if all of it could become modules. That way HVM > device driver domains could load the whole thing without having much > built-in code in the kernel. > > Is it possible to do that? As outlined above, it is possible, but I'm not certain it is a good idea to have balloon_set_new_target() exported. If you think that's acceptable, I can certainly put together a patch doing that (on top of the one here, and probably not immediately). Jan -- 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/