From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932397Ab2AIQl7 (ORCPT ); Mon, 9 Jan 2012 11:41:59 -0500 Received: from mail-tul01m020-f174.google.com ([209.85.214.174]:45819 "EHLO mail-tul01m020-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932178Ab2AIQlz (ORCPT ); Mon, 9 Jan 2012 11:41:55 -0500 Date: Mon, 9 Jan 2012 08:41:48 -0800 From: Tejun Heo To: Namhyung Kim Cc: Jens Axboe , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] block: introduce BIO_IN_FLIGHT flag Message-ID: <20120109164148.GB21732@google.com> References: <1324996113-1837-1-git-send-email-namhyung@gmail.com> <1324996113-1837-2-git-send-email-namhyung@gmail.com> <20120109015628.GB16360@mtj.dyndns.org> <4F0A57A7.4070508@lge.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4F0A57A7.4070508@lge.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Mon, Jan 09, 2012 at 11:57:43AM +0900, Namhyung Kim wrote: > I understand your concerns. However, the blktrace cannot get > bio->bi_flags info in its current form AFAIK. Doing it will require > extending struct blk_io_trace and it'll cause a compatibility issue, > I guess. Umm? Why can't blk_add_trace_bio_complete() look at the flags (or whatever other states) to decide to fire off BLK_TA_COMPLETE or not? What's the difference? No userland visible change is necessary at all. Just make blktrace.c do the right thing. Am I missing something? Thanks. -- tejun