Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753698Ab1EPTDt (ORCPT ); Mon, 16 May 2011 15:03:49 -0400 Received: from lennier.cc.vt.edu ([198.82.162.213]:43226 "EHLO lennier.cc.vt.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752095Ab1EPTDr (ORCPT ); Mon, 16 May 2011 15:03:47 -0400 X-Mailer: exmh version 2.7.2 01/07/2005 with nmh-1.3-dev To: Jean-Christophe PLAGNIOL-VILLARD Cc: Michal Marek , Arnaud Lacombe , linux-kernel@vger.kernel.org, linux-kbuild@vger.kernel.org, x86@kernel.org, Ingo Molnar Subject: Re: [PATCH v2] kconfig: autogenerated config_is_xxx macro In-Reply-To: Your message of "Fri, 13 May 2011 10:09:09 +0200." <20110513080909.GO18952@game.jcrosoft.org> From: Valdis.Kletnieks@vt.edu References: <1304658229-30820-1-git-send-email-plagnioj@jcrosoft.com> <20110507015041.GA21017@game.jcrosoft.org> <4DC7AB57.9050002@suse.cz> <20110513080909.GO18952@game.jcrosoft.org> Mime-Version: 1.0 Content-Type: multipart/signed; boundary="==_Exmh_1305572616_2487P"; micalg=pgp-sha1; protocol="application/pgp-signature" Content-Transfer-Encoding: 7bit Date: Mon, 16 May 2011 15:03:36 -0400 Message-ID: <32557.1305572616@localhost> X-Mirapoint-Received-SPF: 198.82.161.152 auth3.smtp.vt.edu Valdis.Kletnieks@vt.edu 2 pass X-Mirapoint-IP-Reputation: reputation=neutral-1, source=Fixed, refid=n/a, actions=MAILHURDLE SPF TAG X-Junkmail-Status: score=10/50, host=steiner.cc.vt.edu X-Junkmail-Signature-Raw: score=unknown, refid=str=0001.0A020207.4DD1750A.01B0,ss=1,fgs=0, ip=0.0.0.0, so=2010-07-22 22:03:31, dmn=2009-09-10 00:05:08, mode=single engine X-Junkmail-IWF: false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1952 Lines: 54 --==_Exmh_1305572616_2487P Content-Type: text/plain; charset="us-ascii" Content-Id: <32544.1305572608.1@localhost> On Fri, 13 May 2011 10:09:09 +0200, Jean-Christophe PLAGNIOL-VILLARD said: > On 10:52 Mon 09 May , Michal Marek wrote: > > Do you have proof of concept patches that make use of the > > config_is_xxx macros? Acked by the respective subsystem maintainers? > > It would be a good idea to send them along to show that this feature > > is going to be actually used. > I've seen thousands of place in the kernel we can use > so I'll just take one example on x86 > > the patch attached is just an example Out of curiosity, will this Do The Right Thing for cases where things simply won't build for some configs? For example, consider this code snippet from kernel/timer.c, in __mod_timer() (near line 682): debug_activate(timer, expires); cpu = smp_processor_id(); #if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP) if (!pinned && get_sysctl_timer_migration() && idle_cpu(cpu)) cpu = get_nohz_timer_target(); #endif new_base = per_cpu(tvec_bases, cpu); If you convert this to an if statement, will it still compile? Which will happen first, dead code elimination, or the warning that get_nohz_timer_target() is an implicit declaration because the definition in the .h file is also guarded by #ifdef CONFIG_NO_HZ? --==_Exmh_1305572616_2487P Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) Comment: Exmh version 2.5 07/13/2001 iD8DBQFN0XUIcC3lWbTT17ARAu2zAJ4uu2R/V7QCOqmmFRtJXAzt7sm7QQCguF2W alrd+r7GTKDUwKSMvzpOJMg= =qJza -----END PGP SIGNATURE----- --==_Exmh_1305572616_2487P-- -- 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/