From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751591AbdAYPQN (ORCPT ); Wed, 25 Jan 2017 10:16:13 -0500 Received: from mx1.redhat.com ([209.132.183.28]:48414 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751094AbdAYPP6 (ORCPT ); Wed, 25 Jan 2017 10:15:58 -0500 From: Jeff Moyer To: Christoph Hellwig Cc: Toshi Kani , akpm@linux-foundation.org, dan.j.williams@intel.com, linux-nvdimm@ml01.01.org, david@fromorbit.com, linux-kernel@vger.kernel.org, Joe Perches , viro@zeniv.linux.org.uk, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH v5] DAX: enable iostat for read/write References: <20170112183848.23159-1-toshi.kani@hpe.com> <20170125111952.GA11978@infradead.org> X-PGP-KeyID: 1F78E1B4 X-PGP-CertKey: F6FE 280D 8293 F72C 65FD 5A58 1FF8 A7CA 1F78 E1B4 X-PCLoadLetter: What the f**k does that mean? Date: Wed, 25 Jan 2017 10:15:50 -0500 In-Reply-To: <20170125111952.GA11978@infradead.org> (Christoph Hellwig's message of "Wed, 25 Jan 2017 03:19:52 -0800") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Wed, 25 Jan 2017 15:15:52 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Christoph Hellwig writes: > On Thu, Jan 12, 2017 at 11:38:48AM -0700, Toshi Kani wrote: >> DAX IO path does not support iostat, but its metadata IO path does. >> Therefore, iostat shows metadata IO statistics only, which has been >> confusing to users. >> >> Add iostat support to the DAX read/write path. >> >> Note, iostat still does not support the DAX mmap path as it allows >> user applications to access directly. > > NAK. DAX I/O should not be accounted for block device statistics. Agreed, this is a layering violation. Cheers, Jeff