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=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 E2FEACA9EC2 for ; Tue, 29 Oct 2019 07:58:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BC3FA20862 for ; Tue, 29 Oct 2019 07:58:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727170AbfJ2H6p (ORCPT ); Tue, 29 Oct 2019 03:58:45 -0400 Received: from verein.lst.de ([213.95.11.211]:38634 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726233AbfJ2H6p (ORCPT ); Tue, 29 Oct 2019 03:58:45 -0400 Received: by verein.lst.de (Postfix, from userid 2407) id 7CEC368AFE; Tue, 29 Oct 2019 08:58:43 +0100 (CET) Date: Tue, 29 Oct 2019 08:58:43 +0100 From: Christoph Hellwig To: "Darrick J. Wong" Cc: Christoph Hellwig , linux-xfs@vger.kernel.org Subject: Re: [PATCH 4/8] xfs: don't log the inode in xfs_fs_map_blocks if it wasn't modified Message-ID: <20191029075843.GD18999@lst.de> References: <20191025150336.19411-1-hch@lst.de> <20191025150336.19411-5-hch@lst.de> <20191028161245.GD15222@magnolia> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191028161245.GD15222@magnolia> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Mon, Oct 28, 2019 at 09:12:45AM -0700, Darrick J. Wong wrote: > On Fri, Oct 25, 2019 at 05:03:32PM +0200, Christoph Hellwig wrote: > > Even if we are asked for a write layout there is no point in logging > > the inode unless we actually modified it in some way. > > > > Signed-off-by: Christoph Hellwig > > --- > > fs/xfs/xfs_pnfs.c | 43 +++++++++++++++++++------------------------ > > 1 file changed, 19 insertions(+), 24 deletions(-) > > > > diff --git a/fs/xfs/xfs_pnfs.c b/fs/xfs/xfs_pnfs.c > > index 9c96493be9e0..fa90c6334c7c 100644 > > --- a/fs/xfs/xfs_pnfs.c > > +++ b/fs/xfs/xfs_pnfs.c > > @@ -147,32 +147,27 @@ xfs_fs_map_blocks( > > if (error) > > goto out_unlock; > > > > - if (write) { > > - enum xfs_prealloc_flags flags = 0; > > - > > + if (write && > > + (!nimaps || imap.br_startblock == HOLESTARTBLOCK)) { > > ASSERT(imap.br_startblock != DELAYSTARTBLOCK); > > The change in code flow makes this assert rather useless, I think, since > we only end up in this branch if we have a write and a hole. If the > condition that it checks is important (and it seems to be?) then it > ought to be hoisted up a level and turned into: > > ASSERT(!write || !nimaps || imap.br_startblock != DELAYSTARTBLOCK); > > Right? Actually even for !write we should not see delalloc blocks here. So I'll fix up the assert in a separate prep patch.