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=-16.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 F1EA2C4708F for ; Tue, 1 Jun 2021 19:53:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D7EC1613C1 for ; Tue, 1 Jun 2021 19:53:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234723AbhFATzJ (ORCPT ); Tue, 1 Jun 2021 15:55:09 -0400 Received: from mail.kernel.org ([198.145.29.99]:38286 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233853AbhFATzG (ORCPT ); Tue, 1 Jun 2021 15:55:06 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 7DEBE6023B; Tue, 1 Jun 2021 19:53:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1622577204; bh=Kn+xm7L0+263Q+pPrjDNjaUNxSJM6DylX5ppu5+SrD0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=J6/IzPi3NlytE1wWsLXNVxGE53YKLxmEeRKRHWa4L9b6gBVQNUWDIMHHwKOnHRJBU Klv4TyzxnabvyfjsQX4HLpt09lgJKLst1tcaQp9S+Ywj9XE5mg8gF9WhdcjJR4NNqZ EIBVwJUynIPsEVWsiq8+3g8iAjwu14Sh5mDo1w8Zyr8womEuk7D2yz5Y8V/xHiVFcc MPDLLpe8mD60i3COdnmlwCf/avwZBhToSc0ov0p1go8A5OadkPw+Wg3xCkThFPjSc7 mTdnMJF5twROhNUsLAenxOGAHlWb2qkRuPeWXHLUamKFl+9dVQIoYkxmQ144BrZRht Haj0rlWxPtFQg== Date: Tue, 1 Jun 2021 12:53:24 -0700 From: "Darrick J. Wong" To: Dave Chinner Cc: linux-xfs@vger.kernel.org, hch@infradead.org Subject: Re: [PATCH 4/5] xfs: drop inactive dquots before inactivating inodes Message-ID: <20210601195324.GC26380@locust> References: <162250085103.490412.4291071116538386696.stgit@locust> <162250087317.490412.346108244268292896.stgit@locust> <20210601003506.GZ664593@dread.disaster.area> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210601003506.GZ664593@dread.disaster.area> Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Tue, Jun 01, 2021 at 10:35:06AM +1000, Dave Chinner wrote: > On Mon, May 31, 2021 at 03:41:13PM -0700, Darrick J. Wong wrote: > > From: Darrick J. Wong > > > > During quotaoff, the incore inode scan to detach dquots from inodes > > won't touch inodes that have lost their VFS state but haven't yet been > > queued for reclaim. This isn't strictly a problem because we drop the > > dquots at the end of inactivation, but if we detect this situation > > before starting inactivation, we can drop the inactive dquots early to > > avoid delaying quotaoff further. > > > > Signed-off-by: Darrick J. Wong > > --- > > fs/xfs/xfs_super.c | 32 ++++++++++++++++++++++++++++---- > > 1 file changed, 28 insertions(+), 4 deletions(-) > > > > > > diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c > > index a2dab05332ac..79f1cd1a0221 100644 > > --- a/fs/xfs/xfs_super.c > > +++ b/fs/xfs/xfs_super.c > > @@ -637,22 +637,46 @@ xfs_fs_destroy_inode( > > struct inode *inode) > > { > > struct xfs_inode *ip = XFS_I(inode); > > + struct xfs_mount *mp = ip->i_mount; > > > > trace_xfs_destroy_inode(ip); > > > > ASSERT(!rwsem_is_locked(&inode->i_rwsem)); > > - XFS_STATS_INC(ip->i_mount, vn_rele); > > - XFS_STATS_INC(ip->i_mount, vn_remove); > > + XFS_STATS_INC(mp, vn_rele); > > + XFS_STATS_INC(mp, vn_remove); > > + > > + /* > > + * If a quota type is turned off but we still have a dquot attached to > > + * the inode, detach it before processing this inode to avoid delaying > > + * quotaoff for longer than is necessary. > > + * > > + * The inode has no VFS state and hasn't been tagged for any kind of > > + * reclamation, which means that iget, quotaoff, blockgc, and reclaim > > + * will not touch it. It is therefore safe to do this locklessly > > + * because we have the only reference here. > > + */ > > + if (!XFS_IS_UQUOTA_ON(mp)) { > > + xfs_qm_dqrele(ip->i_udquot); > > + ip->i_udquot = NULL; > > + } > > + if (!XFS_IS_GQUOTA_ON(mp)) { > > + xfs_qm_dqrele(ip->i_gdquot); > > + ip->i_gdquot = NULL; > > + } > > + if (!XFS_IS_PQUOTA_ON(mp)) { > > + xfs_qm_dqrele(ip->i_pdquot); > > + ip->i_pdquot = NULL; > > + } > > > > xfs_inactive(ip); > > Shouldn't we just make xfs_inactive() unconditionally detatch dquots > rather than just in the conditional case it does now after attaching > dquots because it has to make modifications? For inodes that don't > require any inactivation work, we get the same thing, and for those > that do running a few extra transactions before dropping the dquots > isn't going to make a huge difference to the quotaoff latency.... Actually... the previous patch does exactly that. I'll drop this patch. --D > > Cheers, > > Dave. > -- > Dave Chinner > david@fromorbit.com