From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753157AbdFSQD1 (ORCPT ); Mon, 19 Jun 2017 12:03:27 -0400 Received: from zeniv.linux.org.uk ([195.92.253.2]:39278 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752552AbdFSQDZ (ORCPT ); Mon, 19 Jun 2017 12:03:25 -0400 Date: Mon, 19 Jun 2017 17:03:16 +0100 From: Al Viro To: Sean Fu Cc: shli@kernel.org, anton@tuxera.com, jack@suse.cz, axboe@fb.com, ebiggers@google.com, rpeterso@redhat.com, bmarzins@redhat.com, linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-ntfs-dev@lists.sourceforge.net Subject: Re: [PATCH] fs: buffer: Modify alloc_page_buffers. Message-ID: <20170619160315.GD10672@ZenIV.linux.org.uk> References: <1497877296-22441-1-git-send-email-fxinrong@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1497877296-22441-1-git-send-email-fxinrong@gmail.com> User-Agent: Mutt/1.8.0 (2017-02-23) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jun 19, 2017 at 09:01:36PM +0800, Sean Fu wrote: > Make alloc_page_buffers support circular buffer list and initialise > b_state field. > Optimize the performance by removing the buffer list traversal to create > circular buffer list. > - bh = head = alloc_page_buffers(page, blocksize, 1); > + bh = head = alloc_page_buffers(page, blocksize, 1, 0, 0); Frankly, I don't like that change of calling conventions; it's very easy to mess the order of arguments when using interfaces like that and it's hell to find when trying to debug the resulting mess. Do you really get an observable change in performance? What loads are triggering it?