Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751964AbbD3QAw (ORCPT ); Thu, 30 Apr 2015 12:00:52 -0400 Received: from cantor2.suse.de ([195.135.220.15]:55444 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750823AbbD3QAt (ORCPT ); Thu, 30 Apr 2015 12:00:49 -0400 Date: Thu, 30 Apr 2015 18:00:44 +0200 From: Borislav Petkov To: "Luis R. Rodriguez" Cc: mingo@elte.hu, tglx@linutronix.de, hpa@zytor.com, plagnioj@jcrosoft.com, tomi.valkeinen@ti.com, daniel.vetter@intel.com, airlied@linux.ie, dledford@redhat.com, awalls@md.metrocast.net, syrjala@sci.fi, luto@amacapital.net, mst@redhat.com, cocci@systeme.lip6.fr, linux-kernel@vger.kernel.org, "Luis R. Rodriguez" , Juergen Gross , Daniel Vetter , Dave Airlie , Bjorn Helgaas , x86@kernel.org Subject: Re: [PATCH v4 2/8] init.h: add __read_mostly to early_param_on_off() Message-ID: <20150430160044.GF5117@pd.tnic> References: <1430343867-1001-1-git-send-email-mcgrof@do-not-panic.com> <1430343867-1001-3-git-send-email-mcgrof@do-not-panic.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1430343867-1001-3-git-send-email-mcgrof@do-not-panic.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2083 Lines: 62 On Wed, Apr 29, 2015 at 02:44:21PM -0700, Luis R. Rodriguez wrote: > From: "Luis R. Rodriguez" So this one is missing a commit message too but we need to talk about this. Why are we adding __read_mostly in the macro? This would put every param declared this way into __section__(".data..read_mostly") and I'm not really convinced that is needed. Those setup params get accessed a couple of times only during boot, in non-critical paths so we don't really care. If you care about pat_enabled being read a lot, you could do: int __read_mostly pat_enabled; only for it. But for every param declared this way? I'm not sure we want that... > Cc: Andy Walls > Cc: Doug Ledford > Cc: Andy Lutomirski > Cc: Ingo Molnar > Cc: Thomas Gleixner > Cc: Juergen Gross > Cc: Daniel Vetter > Cc: Dave Airlie > Cc: Bjorn Helgaas > Cc: Borislav Petkov > Cc: Michael S. Tsirkin > Cc: linux-kernel@vger.kernel.org > Cc: x86@kernel.org > Signed-off-by: Luis R. Rodriguez > --- > include/linux/init.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/include/linux/init.h b/include/linux/init.h > index 21b6d76..a0385cc 100644 > --- a/include/linux/init.h > +++ b/include/linux/init.h > @@ -272,7 +272,7 @@ struct obs_kernel_param { > > #define early_param_on_off(str_on, str_off, var, config) \ > \ > - int var = IS_ENABLED(config); \ > + int __read_mostly var = IS_ENABLED(config); \ > \ > static int __init parse_##var##_on(char *arg) \ > { \ -- Regards/Gruss, Boris. ECO tip #101: Trim your mails when you reply. -- -- 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/