From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030201AbVIVD16 (ORCPT ); Wed, 21 Sep 2005 23:27:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030202AbVIVD15 (ORCPT ); Wed, 21 Sep 2005 23:27:57 -0400 Received: from smtp205.mail.sc5.yahoo.com ([216.136.129.95]:39348 "HELO smtp205.mail.sc5.yahoo.com") by vger.kernel.org with SMTP id S1030201AbVIVD15 (ORCPT ); Wed, 21 Sep 2005 23:27:57 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com.au; h=Received:Message-ID:Date:From:User-Agent:X-Accept-Language:MIME-Version:To:CC:Subject:References:In-Reply-To:Content-Type:Content-Transfer-Encoding; b=vvUft79TI15bnompUBCiAkCqvmz0PryDbOaKnZ2U3EPUwCSIx2xwxlT8eO0hAkoDlx6zQiSNEc1MninczCfpRUliqETcaO8sZnEiFl4XZB4shlV3YumuFYquFr4nwL1mWSxJlWZJyMZTXC95ZdyhBmtYlwzS/SHqk0PlWvzqPxc= ; Message-ID: <433224BC.1000904@yahoo.com.au> Date: Thu, 22 Sep 2005 13:27:56 +1000 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.10) Gecko/20050802 Debian/1.7.10-1 X-Accept-Language: en MIME-Version: 1.0 To: Daniel Walker CC: mingo@elte.hu, linux-kernel@vger.kernel.org Subject: Re: [PATCH] RT: Checks for cmpxchg in get_task_struct_rcu() References: <1127345874.19506.43.camel@dhcp153.mvista.com> <433201FC.8040004@yahoo.com.au> <1127355538.8950.1.camel@c-67-188-6-232.hsd1.ca.comcast.net> In-Reply-To: <1127355538.8950.1.camel@c-67-188-6-232.hsd1.ca.comcast.net> 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 Daniel Walker wrote: > On Thu, 2005-09-22 at 10:59 +1000, Nick Piggin wrote: > > >>You need my atomic_cmpxchg patches that provide an atomic_cmpxchg >>(and atomic_inc_not_zero) for all architectures. >> > > > It is racy, but why not just disable preemption .. > Well you haven't, that's the point. You *introduce* racy operation. Anyway, no matter, atomic_cmpxchg will take care of this nicely. -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com