From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay3.corp.sgi.com [198.149.34.15]) by oss.sgi.com (Postfix) with ESMTP id 092B77F52 for ; Mon, 24 Feb 2014 10:06:57 -0600 (CST) Received: from cuda.sgi.com (cuda3.sgi.com [192.48.176.15]) by relay3.corp.sgi.com (Postfix) with ESMTP id 71BE3AC002 for ; Mon, 24 Feb 2014 08:06:53 -0800 (PST) Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by cuda.sgi.com with ESMTP id 6RTBzEyxovU7yvnq for ; Mon, 24 Feb 2014 08:06:52 -0800 (PST) Received: from int-mx01.intmail.prod.int.phx2.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id s1OG6lOU026807 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Mon, 24 Feb 2014 11:06:47 -0500 Date: Mon, 24 Feb 2014 11:01:04 -0500 From: Brian Foster Subject: Re: [PATCH] xfs: be honest about used inodes in statfs Message-ID: <20140224160047.GA13221@bfoster.bfoster> References: <53067DC0.9040800@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <53067DC0.9040800@redhat.com> 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: Eric Sandeen Cc: xfs-oss On Thu, Feb 20, 2014 at 04:12:16PM -0600, Eric Sandeen wrote: > Because we have lazy counters, it's possible that we over-allocate > inodes past the maxicount (imaxpct) limit. > > A previous commit, > > 2fe3366 xfs: ensure f_ffree returned by statfs() is non-negative > > stopped statfs from underflowing f_ffree in this case, but that > only happened when we mis-reported f_files, capped at maxicount. > > Change statfs to report the actual number of inodes allocated, > even if it is greater than maxicount. It's reality. > Deal with it. ;) > > Signed-off-by: Eric Sandeen > --- > > diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c > index f317488..7c7a810 100644 > --- a/fs/xfs/xfs_super.c > +++ b/fs/xfs/xfs_super.c > @@ -1083,7 +1083,6 @@ xfs_fs_statfs( > struct xfs_inode *ip = XFS_I(dentry->d_inode); > __uint64_t fakeinos, id; > xfs_extlen_t lsize; > - __int64_t ffree; > > statp->f_type = XFS_SB_MAGIC; > statp->f_namelen = MAXNAMELEN - 1; > @@ -1100,17 +1099,24 @@ xfs_fs_statfs( > statp->f_blocks = sbp->sb_dblocks - lsize; > statp->f_bfree = statp->f_bavail = > sbp->sb_fdblocks - XFS_ALLOC_SET_ASIDE(mp); > + > + /* Potential number of new inodes in free blocks */ > fakeinos = statp->f_bfree << sbp->sb_inopblog; > + /* Total possible files is current inodes + potential new inodes */ > statp->f_files = > MIN(sbp->sb_icount + fakeinos, (__uint64_t)XFS_MAXINUMBER); > + /* Unless we have maxicount! Then cap it at that */ > if (mp->m_maxicount) > statp->f_files = min_t(typeof(statp->f_files), > statp->f_files, > mp->m_maxicount); > > - /* make sure statp->f_ffree does not underflow */ > - ffree = statp->f_files - (sbp->sb_icount - sbp->sb_ifree); > - statp->f_ffree = max_t(__int64_t, ffree, 0); > + /* But if we already managed to allocate more, let's be honest */ > + statp->f_files = max_t(typeof(statp->f_files), > + sbp->sb_icount, > + statp->f_files); > + > + statp->f_ffree = statp->f_files - (sbp->sb_icount - sbp->sb_ifree); Hi Eric, Would something like the following be equivalent (and accurate?): /* * Potential number of new inodes in free blocks, limited by maxicount. */ fakeinos = statp->f_bfree << sbp->sb_inopblog; if (mp->m_maxicount) fakeinos = mp->m_maxicount > sbp->sb_icount ? MIN(mp->m_maxicount - sbp->sb_icount, fakeinos) : 0; /* Total possible files is current inodes + potential new inodes */ statp->f_files = MIN(sbp->sb_icount + fakeinos, (__uint64_t) XFS_MAXINUMBER); statp->f_ffree = statp->f_files - (sbp->sb_icount - sbp->sb_ifree); Brian > > spin_unlock(&mp->m_sb_lock); > > > _______________________________________________ > xfs mailing list > xfs@oss.sgi.com > http://oss.sgi.com/mailman/listinfo/xfs _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs