Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932249AbcDYLsI (ORCPT ); Mon, 25 Apr 2016 07:48:08 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:60898 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754432AbcDYLsF (ORCPT ); Mon, 25 Apr 2016 07:48:05 -0400 Date: Mon, 25 Apr 2016 04:48:02 -0700 From: Christoph Hellwig To: Waiman Long Cc: Christoph Hellwig , "Theodore Ts'o" , Andreas Dilger , linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, Tejun Heo , Christoph Lameter , Scott J Norton , Douglas Hatch , Toshimitsu Kani Subject: Re: [PATCH v3 1/2] ext4: Pass in DIO_SKIP_DIO_COUNT flag if inode_dio_begin() called Message-ID: <20160425114802.GA15856@infradead.org> References: <1460484775-33359-1-git-send-email-Waiman.Long@hpe.com> <1460484775-33359-2-git-send-email-Waiman.Long@hpe.com> <20160420205801.GA24609@infradead.org> <571918BC.2060007@hpe.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <571918BC.2060007@hpe.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 645 Lines: 12 On Thu, Apr 21, 2016 at 02:15:24PM -0400, Waiman Long wrote: > On 04/20/2016 04:58 PM, Christoph Hellwig wrote: > >FYI, none of the Dax code even needs to ever touch the dio_count, > >as dax I/O can't be asynchronous, and we thus don't need it to protect > >against truncate. I'd suggest to remove it and then end_io callback > >from the DAX code entirely as a start and then move from there. > > Yes, it seems like we may not need to change the dio_count in dax_do_io() > after all. BTW, what do mean by using end_io callback as a start? I mean to remove both the i_dio_count manipulation, and the unessecary end_io callback from dax_do_io.