From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751958Ab2ARLK3 (ORCPT ); Wed, 18 Jan 2012 06:10:29 -0500 Received: from mx4-phx2.redhat.com ([209.132.183.25]:46350 "EHLO mx4-phx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751192Ab2ARLK2 (ORCPT ); Wed, 18 Jan 2012 06:10:28 -0500 Date: Wed, 18 Jan 2012 06:08:30 -0500 (EST) From: Andrew Jones To: drjones@redhat.com, rientjes@google.com, mingo@elte.hu, david.woodhouse@intel.com Cc: linux-kernel@vger.kernel.org, rientjes@google.com, akpm@linux-foundation.org, mingo@elte.hu, david woodhouse , gregkh@suse.de, davem@davemloft.net, axboe@kernel.dk, arnd@arndb.de, holt@sgi.com, linux-arch@vger.kernel.org, linux@arm.linux.org.uk, hskinnemoen@gmail.com, egtvedt@samfundet.no, msalter@redhat.com, a-jacquiot@ti.com, starvik@axis.com, jesper nilsson , dhowells@redhat.com, takata@linux-m32r.org, geert@linux-m68k.org, yasutake koichi , jonas@southpole.se, kyle@mcmartin.ca, deller@gmx.de, jejb@parisc-linux.org, chris@zankel.net, greg@kroah.com, davej@redhat.com, airlied@linux.ie, jkosina@suse.cz, mchehab@infradead.org, johannes@sipsolutions.net, linville@tuxdriver.com Subject: Re: [PATCH] kconfig: untangle EXPERT and EMBEDDED Message-ID: In-Reply-To: <1326295008-29795-1-git-send-email-drjones@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit MIME-Version: 1.0 X-Originating-IP: [10.34.1.174] X-Mailer: Zimbra 7.1.2_GA_3268 (ZimbraWebClient - FF3.0 (Linux)/7.1.2_GA_3268) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ----- Original Message ----- > Commit 6a108a14fa35 renamed CONFIG_EMBEDDED to CONFIG_EXPERT with the > justification that EMBEDDED was being used with a broader scope. It > was > no longer just being used to expose standard options to embedded > kernel > configs for tweaking, but rather for all "non-standard" kernel > configs. > This is nice, because now developers have a way to clean up the > config > menu by adding 'if EXPERT' to all entries in their Kconfig files that > should rarely have a non-default value selected (hint1: it would be > nice > if developers would do this, hint2: it would also be nice if > developers > would do this rather than making these types of options silent, and > thus > impossible to override). > > Unfortunately, EMBEDDED was also being used to modify the defaults of > some of these options to selections more appropriate for embedded > kernels. Since the renaming was a simple global search-replace, if > developers were to follow hints 1 and 2 above for non-embedded > kernels, > then they may find unexpected changes in their configs after turning > on > EXPERT. > > This patch attempts to untangle these two, making EXPERT true to its > purpose, which is to only expose standard options for tweaking, and > EMBEDDED to resume use as a default option modifier. The patch was > made > with the following four steps, which could not be split into separate > patches without breaking configs > > 1. Make sure EMBEDDED does nothing, i.e. s/EMBEDDED/EXPERT/. There > were > only three places EMBEDDED was used. > > 2. Add CONFIG_EXPERT=y to all configs that had CONFIG_EMBEDDED=y (and > not CONFIG_EXPERT=y already) to make sure step1 has no effect. This > step > isn't strictly necessary since EMBEDDED selects EXPERT, but I wanted > the > configs expressing the new need explicitly. Only 13 *_defconfig > files. > > 3. Move all side effects (default changes) from EXPERT to EMBEDDED > > 4. Add CONFIG_EMBEDDED=y to all configs that had CONFIG_EXPERT=y (and > not CONFIG_EMBEDDED=y already) to make sure step3 has no effect. > > I certainly didn't test this for every touched config. However, I did > test it for one config and got the expected results; > Before patch: > 1. diff config.orig orig.EXPERT -- shows many changes > 2. diff config.orig orig.EMBEDDED -- shows same changes as > (1) > plus EMBEDDED on > After patch: > 3. diff config.orig config.new -- no change > 4. diff config.orig new.EXPERT -- only 1 change, EXPERT on > 5. diff config.orig new.EMBEDDED -- shows same changes as > (2) > > Signed-off-by: Andrew Jones > --- This patch is effectively a partial revert of 6a108a14fa35, and has now been nacked by David Rientjes (author of 6a108a14fa35). However, IMO, there hasn't been a sufficient technical explanation for why. I've now added Ingo Molnar and David Woodhouse to the 'To:', in order to try and bring the patch to their attention. Both are listed as having reviewed or acked 6a108a14fa35, so I would appreciate their opinions on this patch as well. Drew