Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965124AbWHOS6j (ORCPT ); Tue, 15 Aug 2006 14:58:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S965226AbWHOS6j (ORCPT ); Tue, 15 Aug 2006 14:58:39 -0400 Received: from gprs189-60.eurotel.cz ([160.218.189.60]:12304 "EHLO spitz.ucw.cz") by vger.kernel.org with ESMTP id S965124AbWHOS6i (ORCPT ); Tue, 15 Aug 2006 14:58:38 -0400 Date: Mon, 14 Aug 2006 20:13:00 +0000 From: Pavel Machek To: Vojtech Pavlik Cc: Andi Kleen , Dmitry Torokhov , Rusty Russell , lkml - Kernel Mailing List Subject: Re: [PATCH] Turn rdmsr, rdtsc into inline functions, clarify names Message-ID: <20060814201300.GA4032@ucw.cz> References: <1154771262.28257.38.camel@localhost.localdomain> <1154832963.29151.21.camel@localhost.localdomain> <20060806031643.GA43490@muc.de> <200608062243.45129.dtor@insightbb.com> <20060807084850.GA67713@muc.de> <20060807110931.GM27757@suse.cz> <20060807122845.GA85602@muc.de> <20060807124855.GB21003@suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060807124855.GB21003@suse.cz> User-Agent: Mutt/1.5.9i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1152 Lines: 31 Hi! > > > > > Would not preempt_disable fix that? > > > > > > > > Partially, but you still have other problems. Please just get rid > > > > of it. Why do we have timer code in the kernel if you then chose > > > > not to use it? > > > > > > The problem is that gettimeofday() is not always fast. > > > > When it is not fast that means it is not reliable and then you're > > also not well off using it anyways. > > I assume you wanted to say "When gettimeofday() is slow, it means TSC is > not reliable", which I agree with. > > But I need, in the driver, in the no-TSC case use i/o counting, not a > slow but reliable method. And I can't say, from outside the timing > subsystem, whether gettimeofday() is fast or slow. do gettimeofday(); gettimeofday(); gettimeofday();, then compare the result with gettimeofday(); inb(); gettimeofday(); ? Pavel -- Thanks for all the (sleeping) penguins. - 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/