From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S266163AbUBCW6P (ORCPT ); Tue, 3 Feb 2004 17:58:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S266171AbUBCW6P (ORCPT ); Tue, 3 Feb 2004 17:58:15 -0500 Received: from fw.osdl.org ([65.172.181.6]:60109 "EHLO mail.osdl.org") by vger.kernel.org with ESMTP id S266163AbUBCW6K (ORCPT ); Tue, 3 Feb 2004 17:58:10 -0500 Date: Tue, 3 Feb 2004 14:59:29 -0800 From: Andrew Morton To: Ingo Molnar Cc: kernel@kolivas.org, linux-kernel@vger.kernel.org, josh@stack.nl Subject: Re: [PATCH] 2.6.1 Hyperthread smart "nice" 2 Message-Id: <20040203145929.01a96d9b.akpm@osdl.org> In-Reply-To: <20040203105758.GA7783@elte.hu> References: <200401291917.42087.kernel@kolivas.org> <200402022027.10151.kernel@kolivas.org> <20040202103122.GA29402@elte.hu> <200402032152.46481.kernel@kolivas.org> <20040203105758.GA7783@elte.hu> X-Mailer: Sylpheed version 0.9.7 (GTK+ 1.2.10; i586-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Ingo Molnar wrote: > > * Con Kolivas wrote: > > > At least it appears Intel are well aware of the priority problem, but > > full priority support across logical cores is not likely. However I > > guess these new instructions are probably enough to work with if > > someone can do the coding. > > these instructions can be used in the idle=poll code instead of rep-nop. > This way idle-wakeup can be done via the memory bus in essence, and the > idle threads wont waste CPU time. (right now idle=poll wastes lots of > cycles on HT boxes and is thus unusable.) The code to do this was merged quite a while ago. See arch/i386/kernel/process.c:mwait_idle(). I was hoping to see a spinlock patch using mwait(), but nothing yet..