Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755507Ab3ETJ7I (ORCPT ); Mon, 20 May 2013 05:59:08 -0400 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:46358 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754822Ab3ETJ7G (ORCPT ); Mon, 20 May 2013 05:59:06 -0400 Date: Mon, 20 May 2013 11:59:04 +0200 From: Pavel Machek To: Nicolas Pitre Cc: Will Deacon , Rob Herring , Marc Zyngier , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" Subject: Re: [RFC PATCH 1/2] ARM: delay: print dummy values for bogomips Message-ID: <20130520095904.GA7279@amd.pavel.ucw.cz> References: <1367602547-19322-1-git-send-email-will.deacon@arm.com> <1367602547-19322-2-git-send-email-will.deacon@arm.com> <20130506231554.GB16801@amd.pavel.ucw.cz> <5188B8B2.5030601@arm.com> <20130515090103.GA12907@mudshark.cambridge.arm.com> <20130515114737.GA7900@amd.pavel.ucw.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1473 Lines: 39 Hi! > > > In fact, I just tried it and at least my linaro filesystem seems happy > > > enough. > > > > Would it be too much work to simply put the field back with the right > > value? We don't have to get it as precise as we used to, that should > > make slowdown minimum. > > There is simply no right value. And whenever there is a value, people > read too much into it. You are right that there is no right value. But there are many _wrong_ values. Take a look at CPU temperature. There's no right value there, either, as CPU has different temperatures at different places. Displaying heatsink temp +5C is probably ok. Displaying case temperature or compile time constant is not. Now, bogoMIPS is supposed to be instructions per second. Measure instructions per second, and you have acceptable value to display. Put back code from previous version, and you have acceptable value to display. "0", "1" or value from Kconfig is _not_ acceptable value. Maybe bogomips should not have been exposed in /proc in the first place, but it is too late now. "No regressions". Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- 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/