From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750897AbWJ0Xen (ORCPT ); Fri, 27 Oct 2006 19:34:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750893AbWJ0Xen (ORCPT ); Fri, 27 Oct 2006 19:34:43 -0400 Received: from agminet01.oracle.com ([141.146.126.228]:42363 "EHLO agminet01.oracle.com") by vger.kernel.org with ESMTP id S1750732AbWJ0Xen (ORCPT ); Fri, 27 Oct 2006 19:34:43 -0400 Message-ID: <4542977E.5030007@oracle.com> Date: Fri, 27 Oct 2006 16:34:22 -0700 From: Zach Brown User-Agent: Thunderbird 1.5.0.7 (X11/20060913) MIME-Version: 1.0 To: Jeff Moyer CC: Andrew Morton , linux-kernel@vger.kernel.org Subject: Re: [PATCH] dio: lock refcount operations References: <20061027181735.18631.43565.sendpatchset@tetsuo.zabbo.net> <45426D3F.3040304@oracle.com> In-Reply-To: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Brightmail-Tracker: AAAAAQAAAAI= X-Brightmail-Tracker: AAAAAQAAAAI= X-Whitelist: TRUE X-Whitelist: TRUE Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > zach.brown> The addition of the interrupt masking spin lock acquiry in > zach.brown> dio_bio_submit() looks alarming. This lock acquiry existed in > zach.brown> that path before the recent dio completion patch set. We > zach.brown> shouldn't expect significant performance regression from > zach.brown> returning to the behaviour that existed before the completion > zach.brown> clean up work. > > Are you going to quantify this at all? I think we should. I could try to take a swing at it next week, sure. Leaving it for Ken is pretty tempting, though :) - z