From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261808AbVFKUEv (ORCPT ); Sat, 11 Jun 2005 16:04:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261804AbVFKUEZ (ORCPT ); Sat, 11 Jun 2005 16:04:25 -0400 Received: from gateway-1237.mvista.com ([12.44.186.158]:27130 "EHLO av.mvista.com") by vger.kernel.org with ESMTP id S261803AbVFKUEQ (ORCPT ); Sat, 11 Jun 2005 16:04:16 -0400 Subject: Re: [PATCH] local_irq_disable removal From: Sven-Thorsten Dietrich To: Esben Nielsen Cc: Ingo Molnar , Daniel Walker , linux-kernel@vger.kernel.org In-Reply-To: References: Content-Type: text/plain Date: Sat, 11 Jun 2005 13:02:59 -0700 Message-Id: <1118520182.5593.31.camel@sdietrich-xp.vilm.net> Mime-Version: 1.0 X-Mailer: Evolution 2.0.4 (2.0.4-4) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > > > Well, isn't enough to see that the code contains more instructions and > looks somewhat more complicated? > And - another thing: Not all instructions take the same amount of time to execute. Think about the cli operation. This can take real time on highly pipelined processors, when compared to a simple increment by one operation. So the more complex-looking code, might make things faster. I'm going to say it one last time. Do the analysis scientifically, and use numbers to get your answers. This stuff is profound. Think it through, and when you find a real problem, then we can take a look together, and see if it requires a bug fix. And consider this - There are robots walking around today, that use this concept in Linux 2.4, and they can help you carry a 20 foot long plank across rugged terrain. In addition, they will stand it up against a wall for you... So be careful when you say it can't be done in 2.6. Sven