From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161631AbXD3Guh (ORCPT ); Mon, 30 Apr 2007 02:50:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1161649AbXD3Guh (ORCPT ); Mon, 30 Apr 2007 02:50:37 -0400 Received: from brick.kernel.dk ([80.160.20.94]:8372 "EHLO kernel.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161631AbXD3Gue (ORCPT ); Mon, 30 Apr 2007 02:50:34 -0400 Date: Mon, 30 Apr 2007 08:46:16 +0200 From: Jens Axboe To: "Alan D. Brunelle" Cc: linux-kernel@vger.kernel.org Subject: Re: [PATCH linux-2.6-block.git] Fix blktrace trace ordering for plug branch Message-ID: <20070430064615.GB21015@kernel.dk> References: <46325A6F.4050705@pobox.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <46325A6F.4050705@pobox.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Apr 27 2007, Alan D. Brunelle wrote: > The attached patch will correct the ordering of trace output between > request queue insertions (I) and unplug calls (U). Right now the insert > precedes the unplug, which just isn't right: > > 65,128 0 1 67.699868965 7882 Q R 0 + 1 [aiod] > 65,128 0 2 67.699876462 7882 G R 0 + 1 [aiod] > 65,128 0 3 67.699878286 7882 P W [aiod] > 65,128 0 4 67.699880491 7882 I R 0 + 1 [aiod] > 65,128 0 5 67.699887589 7882 U R [aiod] 1 > 65,128 0 6 67.699898317 54 D R 0 + 1 [kblockd/0] > 65,128 2 153 67.700126590 0 C R 0 + 1 [0] > > With the patch provided the unplug comes first: > > 65,128 3 1 0.000000000 7045 Q R 0 + 1 [aiod] > 65,128 3 2 0.000002295 7045 G R 0 + 1 [aiod] > 65,128 3 3 0.000002617 7045 P W [aiod] > 65,128 3 4 0.000003685 7045 U R [aiod] 1 > 65,128 3 5 0.000004107 7045 I R 0 + 1 [aiod] > 65,128 3 6 0.000009491 57 D R 0 + 1 [kblockd/3] > 65,128 2 1 0.000232447 0 C R 0 + 1 [0] > > Jens: If you agree, the patch can be applied to your plug branch for > git://git.kernel.dk/data/git/linux-2.6-block.git Thanks, with that applied the unplug ordering should be the same after the plugging changes. Applied. -- Jens Axboe