From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261162AbULIXr1 (ORCPT ); Thu, 9 Dec 2004 18:47:27 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261669AbULIXr1 (ORCPT ); Thu, 9 Dec 2004 18:47:27 -0500 Received: from c7ns3.center7.com ([216.250.142.14]:51358 "EHLO smtp.slc03.viawest.net") by vger.kernel.org with ESMTP id S261162AbULIXrW (ORCPT ); Thu, 9 Dec 2004 18:47:22 -0500 Message-ID: <41B8E6A5.3090103@devicelogics.com> Date: Thu, 09 Dec 2004 16:58:29 -0700 From: "Jeff V. Merkey" User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.6) Gecko/20040510 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Anton Altaparmakov Cc: kernel-stuff@comcast.net, Imanpreet Singh Arora , Linux Kernel Mailing List Subject: Re: Question from Russells Spinlocks References: <120920042115.25628.41B8C082000394E30000641C220076219400009A9B9CD3040A029D0A05@comcast.net> In-Reply-To: Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Anton Altaparmakov wrote: > > >Your last sentence is incorrect. Spinlocks on 1 CPU machines still need >to disable preemption (assuming preemption is compiled in obviously, if >not then indeed you are right). Otherwise preemption could take place in >the middle of a data manipulation and you would still have the same race >as you described with two cpus working concurrently. Except that with >preemption it is only logical concurrence not actual physical concurrence. > >Best regards, > > Anton > > > Anton is correct in his analysis. Jeff