From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay2.corp.sgi.com [137.38.102.29]) by oss.sgi.com (Postfix) with ESMTP id 36ECA7F4E for ; Thu, 5 Sep 2013 11:22:11 -0500 (CDT) Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by relay2.corp.sgi.com (Postfix) with ESMTP id EB30130408B for ; Thu, 5 Sep 2013 09:22:10 -0700 (PDT) Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by cuda.sgi.com with ESMTP id m7tI5cWxr0R9AwjF for ; Thu, 05 Sep 2013 09:22:09 -0700 (PDT) Message-ID: <5228AED7.1010700@redhat.com> Date: Thu, 05 Sep 2013 12:18:31 -0400 From: Brian Foster MIME-Version: 1.0 Subject: Re: [RFC PATCH 07/11] xfs: retry trans reservation on ENOSPC in xfs_inactive() References: <1378232708-57156-1-git-send-email-bfoster@redhat.com> <1378232708-57156-8-git-send-email-bfoster@redhat.com> <20130905014016.GU23571@dastard> In-Reply-To: <20130905014016.GU23571@dastard> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Dave Chinner Cc: xfs@oss.sgi.com On 09/04/2013 09:40 PM, Dave Chinner wrote: > On Tue, Sep 03, 2013 at 02:25:04PM -0400, Brian Foster wrote: >> An ifree data block reservation can fail with ENOSPC. Flush inodes >> to try and free up space or attempt without a data block >> reservation to avoid failing out of xfs_inactive(). >> >> Signed-off-by: Brian Foster >> --- >> fs/xfs/xfs_inode.c | 11 +++++++++++ >> 1 file changed, 11 insertions(+) >> >> diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c >> index 56cbf63..92de4b7 100644 >> --- a/fs/xfs/xfs_inode.c >> +++ b/fs/xfs/xfs_inode.c >> @@ -1779,7 +1779,18 @@ xfs_inactive( >> tp = xfs_trans_alloc(mp, XFS_TRANS_INACTIVE); >> error = xfs_trans_reserve(tp, &M_RES(mp)->tr_ifree, >> XFS_IFREE_SPACE_RES(mp), 0); >> + if (error == ENOSPC) { >> + /* flush outstanding delalloc blocks and retry */ >> + xfs_flush_inodes(mp); >> + error = xfs_trans_reserve(tp, &M_RES(mp)->tr_ifree, >> + XFS_IFREE_SPACE_RES(mp), 0); >> + } > > We don't want to be blocking for inode flushes here. We might be in > a shrinker context, for example, and blocking those for a filesystem > sync is going to be unfriendly. > Ok. > If this really is a problem, then the right thing to do is to allow > this transaction to dip into the reserve block pool so the > transaction can complete and make progress - other write operations > will trigger the flushing of the filesystem, and freeing of whole > inode chunks should return more free space than we need for the > finobt modifications in the removing lots of zero length inodes > at ENOSPC case.... > I did have one of the enospc xfstests lead to this situation, though I don't have the particular test in my notes. It initially manifested as an assert failure due to the fs not being shutdown after an xfs_trans_reserve() ENOSPC failure. Subsequent to avoiding that, I believe there were inconsistent fs issues called out due to the unlinked lists being populated after umount. Taking a further look, I missed the XFS_TRANS_RESERVE flag and whole m_resblks mechanism. I'll take a closer look at that and see if that works to resolve the problem instead of the flush. Brian > Cheers, > > Dave. > _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs