From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steven Whitehouse Date: Wed, 14 Mar 2007 14:50:34 +0000 Subject: [Cluster-devel] [GFS2] Fix bz 231380, unlock page before dequeing glocks in gfs2_commit_write In-Reply-To: <20070312215505.GA6083@korben.rdu.redhat.com> References: <20070312215505.GA6083@korben.rdu.redhat.com> Message-ID: <1173883834.32601.86.camel@quoit.chygwyn.com> List-Id: To: cluster-devel.redhat.com MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Hi, Now applied to the -nmw git tree. I think this is the right fix, at least for now, Steve. On Mon, 2007-03-12 at 16:55 -0500, Josef Whiter wrote: > Hello, > > I'm not entirely sure if this is the best fix for this problem, so I'm open for > suggetions. If we are writing a file, and in the middle of writing the file > another node attempts to get a shared lock on that file (by doing a du for > example) the process doing the writing will hang waiting on lock_page. The > reason for this is because when we have waiters on a exclusive glock, we will go > through and flush out all dirty pages associated with that inode and release the > lock. The problem is that when we flush the dirty pages, we could hit a page > that we have locked durring the generic_file_buffered_write part of this > operation. This patch unlocks the page before we go to dequeue the lock and > locks it immediatly afterwards, since generic_file_buffered_write needs the page > locked when the commit_write is completed. This patch resolves the problem, > however if somebody sees a better way to do this please don't hesistate to yell. > Thank you, > > Josef > > > Signed-off-by: Josef Whiter > > > --- gfs2-2.6-nmw/fs/gfs2/ops_address.c.josef 2007-03-08 15:04:10.000000000 -0500 > +++ gfs2-2.6-nmw/fs/gfs2/ops_address.c 2007-03-12 17:23:24.000000000 -0400 > @@ -507,7 +507,9 @@ > gfs2_quota_unlock(ip); > gfs2_alloc_put(ip); > } > + unlock_page(page); > gfs2_glock_dq_m(1, &ip->i_gh); > + lock_page(page); > gfs2_holder_uninit(&ip->i_gh); > return 0; > > @@ -520,7 +522,9 @@ > gfs2_quota_unlock(ip); > gfs2_alloc_put(ip); > } > + unlock_page(page); > gfs2_glock_dq_m(1, &ip->i_gh); > + lock_page(page); > gfs2_holder_uninit(&ip->i_gh); > fail_nounlock: > ClearPageUptodate(page); >