From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B4EA8C43610 for ; Wed, 21 Nov 2018 15:07:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8865121479 for ; Wed, 21 Nov 2018 15:07:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8865121479 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731224AbeKVBmL (ORCPT ); Wed, 21 Nov 2018 20:42:11 -0500 Received: from mx1.redhat.com ([209.132.183.28]:34052 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729828AbeKVBmJ (ORCPT ); Wed, 21 Nov 2018 20:42:09 -0500 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 65ADB3002F82; Wed, 21 Nov 2018 15:07:21 +0000 (UTC) Received: from ming.t460p (ovpn-8-20.pek2.redhat.com [10.72.8.20]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 0B9468271A; Wed, 21 Nov 2018 15:06:15 +0000 (UTC) Date: Wed, 21 Nov 2018 23:06:11 +0800 From: Ming Lei To: Christoph Hellwig Cc: Jens Axboe , linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Theodore Ts'o , Omar Sandoval , Sagi Grimberg , Dave Chinner , Kent Overstreet , Mike Snitzer , dm-devel@redhat.com, Alexander Viro , linux-fsdevel@vger.kernel.org, Shaohua Li , linux-raid@vger.kernel.org, David Sterba , linux-btrfs@vger.kernel.org, "Darrick J . Wong" , linux-xfs@vger.kernel.org, Gao Xiang , linux-ext4@vger.kernel.org, Coly Li , linux-bcache@vger.kernel.org, Boaz Harrosh , Bob Peterson , cluster-devel@redhat.com Subject: Re: [PATCH V11 02/19] block: introduce multi-page bvec helpers Message-ID: <20181121150610.GA19111@ming.t460p> References: <20181121032327.8434-1-ming.lei@redhat.com> <20181121032327.8434-3-ming.lei@redhat.com> <20181121131928.GA1640@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181121131928.GA1640@lst.de> User-Agent: Mutt/1.9.1 (2017-09-22) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.47]); Wed, 21 Nov 2018 15:07:21 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 21, 2018 at 02:19:28PM +0100, Christoph Hellwig wrote: > On Wed, Nov 21, 2018 at 11:23:10AM +0800, Ming Lei wrote: > > This patch introduces helpers of 'segment_iter_*' for multipage > > bvec support. > > > > The introduced helpers treate one bvec as real multi-page segment, > > which may include more than one pages. > > Unless I'm missing something these bvec vs segment names are exactly > inverted vs how we use it elsewhere. > > In the iterators we use segment for single-page bvec, and bvec for multi > page ones, and here it is inverse. Please switch it around. bvec_iter_* is used for single-page bvec in current linus tree, and there are lots of users now: [linux]$ git grep -n "bvec_iter_*" ./ | wc 191 995 13242 If we have to switch it first, it can be a big change, just wondering if Jens is happy with that? Thanks, Ming