From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265405AbUFHXgS (ORCPT ); Tue, 8 Jun 2004 19:36:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265428AbUFHXgS (ORCPT ); Tue, 8 Jun 2004 19:36:18 -0400 Received: from holomorphy.com ([207.189.100.168]:3713 "EHLO holomorphy.com") by vger.kernel.org with ESMTP id S265405AbUFHXgR (ORCPT ); Tue, 8 Jun 2004 19:36:17 -0400 Date: Tue, 8 Jun 2004 16:36:10 -0700 From: William Lee Irwin III To: Peter Williams Cc: Con Kolivas , Linux Kernel Mailinglist , Zwane Mwaikambo Subject: Re: [PATCH] staircase scheduler v6.4 for 2.6.7-rc3 Message-ID: <20040608233610.GC1444@holomorphy.com> Mail-Followup-To: William Lee Irwin III , Peter Williams , Con Kolivas , Linux Kernel Mailinglist , Zwane Mwaikambo References: <200406090023.54421.kernel@kolivas.org> <40C645F7.6070704@bigpond.net.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <40C645F7.6070704@bigpond.net.au> User-Agent: Mutt/1.5.5.1+cvs20040105i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 09, 2004 at 09:04:23AM +1000, Peter Williams wrote: > There was no need to add the extra overhead of a flag to indicate that a > task was queued for scheduling. Testing whether run_list is empty > achieves the same thing as reliably as the old array == NULL test did. Overhead? Doubtful. Also, that requires the use of list_del_init() while dequeueing, which is not in place now. Please do back the claim with measurements. It should be easy enough to nop out set_task_queued(), implement task_queued() via !list_empty(), and clear_task_queued() via INIT_LIST_HEAD() for a quick performance comparison. But I'd say to merge it even if there's no difference, as it's more self-contained. -- wli