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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1002DC001DC for ; Fri, 14 Jul 2023 14:30:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235819AbjGNOav (ORCPT ); Fri, 14 Jul 2023 10:30:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45088 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235769AbjGNOau (ORCPT ); Fri, 14 Jul 2023 10:30:50 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C05761BFB for ; Fri, 14 Jul 2023 07:30:08 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id CEF6261D1A for ; Fri, 14 Jul 2023 14:30:07 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D7534C433C9; Fri, 14 Jul 2023 14:30:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1689345007; bh=OBfJCS92UzmsLadHmYPGtlTmmiWzY0ooE0gwKVu0LDk=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=RyYsF45hKkn2Y7NdN/Oc6NC0mhrD/MKM+C0Lm+7AqC7TxahYt1lnmKIaDCioB1HT8 gSlLz5/clvYGb9s5bxIXrdJ5wVrvRYTcHsBSfjDmquHoA5vMZJ6ulXO5t1Y7UTVDcU SouOIh7Wyoj/RJN/DqkZzLyKPwGCily96IGFVq8746JYbnWWokcHJCc1opRg48Aw98 BYrl5m8zM7RSCVY90Iu/Q66XzK1+F2bEOy27xN3iV4oEEle7AmkmUI306TX1+MIwA6 VcDWspZgvdKOYQwyaxSG6ua4ayigUBJoDoJbMxV8vAugK414BwVDdVJaOdEJJg19q4 6C6X5VWlpnq5w== Message-ID: <872eb33d7a7c58f7223faa79f2bda7677b8ee264.camel@kernel.org> Subject: Re: [PATCH v5 5/8] xfs: XFS_ICHGTIME_CREATE is unused From: Jeff Layton To: "Darrick J. Wong" Cc: Anthony Iliopoulos , linux-xfs@vger.kernel.org Date: Fri, 14 Jul 2023 10:30:05 -0400 In-Reply-To: <20230714141632.GU108251@frogsfrogsfrogs> References: <20230713-mgctime-v5-0-9eb795d2ae37@kernel.org> <20230713-mgctime-v5-5-9eb795d2ae37@kernel.org> <2b782aa87e50d6ee9195a9725fef2d56d52d8afe.camel@kernel.org> <20230714063502.GS108251@frogsfrogsfrogs> <6a2e25d21dde5e376af85ed5b691a0ddbb9cd478.camel@kernel.org> <20230714141632.GU108251@frogsfrogsfrogs> Content-Type: text/plain; charset="ISO-8859-15" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.48.4 (3.48.4-1.fc38) MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Fri, 2023-07-14 at 07:16 -0700, Darrick J. Wong wrote: > On Fri, Jul 14, 2023 at 06:53:45AM -0400, Jeff Layton wrote: > > On Thu, 2023-07-13 at 23:35 -0700, Darrick J. Wong wrote: > > > On Thu, Jul 13, 2023 at 08:15:21PM -0400, Jeff Layton wrote: > > > > On Fri, 2023-07-14 at 01:53 +0200, Anthony Iliopoulos wrote: > > > > > On Thu, Jul 13, 2023 at 07:00:54PM -0400, Jeff Layton wrote: > > > > > > Nothing ever sets this flag, which makes sense since the create= time is > > > > > > set at inode instantiation and is never changed. Remove it and = the > > > > > > handling of it in xfs_trans_ichgtime. > > > > >=20 > > > > > It is currently used by xfs_repair during recreating the root ino= de and > > > > > the internal realtime inodes when needed (libxfs is exported to x= fsprogs > > > > > so there are userspace consumers of this code). > > > > >=20 > > > >=20 > > > > Ahh thanks. I didn't think to look at userland for this. We can dro= p > > > > this patch, and I'll respin #6. > > > >=20 > > > > Looking briefly at xfsprogs, it looks like XFS_ICHGTIME_CREATE is n= ever > > > > set without also setting XFS_ICHGTIME_CHG. Is that safe assumption? > > >=20 > > > There are four timestamps in an xfs inode and an ICHGTIME flag for ea= ch: > > > MOD is mtime, CHG is ctime, CREATE is crtime/btime, and ACCESS is ati= me. > > > I'd rather leave it that way than tie flags together. > > >=20 > > >=20 > >=20 > > I wasn't suggesting to tie any flags together. I just don't see any > > scenario where it's OK to call xfs_trans_ichgtime() without > > XFS_ICHGTIME_CHG set. It has to change if either of the other times > > change. >=20 > Oh! That's correct, I don't know of any place where the [bam]time get > updated without also bumping ctime. >=20 Great! Thanks for confirming. With that, patch #6 has this delta in it instead: diff --git a/fs/xfs/libxfs/xfs_trans_inode.c b/fs/xfs/libxfs/xfs_trans_inod= e.c index 6b2296ff248a..3ac1fcca7c52 100644 --- a/fs/xfs/libxfs/xfs_trans_inode.c +++ b/fs/xfs/libxfs/xfs_trans_inode.c @@ -62,12 +62,12 @@ xfs_trans_ichgtime( ASSERT(tp); ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL)); =20 - tv =3D current_time(inode); + /* If the mtime or btime change, then ctime must also change */ + WARN_ON_ONCE(!(flags & XFS_ICHGTIME_CHG)); =20 + tv =3D inode_set_ctime_current(inode); if (flags & XFS_ICHGTIME_MOD) inode->i_mtime =3D tv; - if (flags & XFS_ICHGTIME_CHG) - inode_set_ctime_to_ts(inode, tv); if (flags & XFS_ICHGTIME_CREATE) ip->i_crtime =3D tv; }