From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262119AbTLNQ0Z (ORCPT ); Sun, 14 Dec 2003 11:26:25 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262123AbTLNQ0Z (ORCPT ); Sun, 14 Dec 2003 11:26:25 -0500 Received: from ns.suse.de ([195.135.220.2]:51080 "EHLO Cantor.suse.de") by vger.kernel.org with ESMTP id S262119AbTLNQ0Y (ORCPT ); Sun, 14 Dec 2003 11:26:24 -0500 To: Arjan van de Ven Cc: linux-kernel@vger.kernel.org Subject: Re: [CFT][RFC] HT scheduler References: <20031213022038.300B22C2C1@lists.samba.org.suse.lists.linux.kernel> <3FDAB517.4000309@cyberone.com.au.suse.lists.linux.kernel> <3FDBC876.3020603@cyberone.com.au.suse.lists.linux.kernel> <20031214043245.GC21241@mail.shareable.org.suse.lists.linux.kernel> <3FDC3023.9030708@cyberone.com.au.suse.lists.linux.kernel> <1071398761.5233.1.camel@laptop.fenrus.com.suse.lists.linux.kernel> From: Andi Kleen Date: 14 Dec 2003 17:26:23 +0100 In-Reply-To: <1071398761.5233.1.camel@laptop.fenrus.com.suse.lists.linux.kernel> Message-ID: User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.2 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Arjan van de Ven writes: > > also keep in mind that current x86 processors all will internally > optimize out the lock prefix in UP mode or when the cacheline is owned > exclusive.... If HT matters here let the cpu optimize it out..... Are you sure they optimize it out in UP mode? IMHO this would break device drivers that use locked cycles to communicate with bus master devices (and which are not necessarily mapped uncachable/write combining) -Andi