On Sun, 19 Aug 2012, Sage Weil wrote:
> On Sun, 19 Aug 2012, Alexandre Oliva wrote:
> > On Aug 18, 2012, Alexandre Oliva <oliva@xxxxxxxxxxxxxxxxx> wrote:
> >
> > > I've looked further into this tonight, and I found out what modifies
> > > the timestamps in the inode is (re)issuing caps to a client.
> >
> > > So, how can we stop pre_cow_old_inode from messing with the old_inode?
> > > Any suggestions?
> >
> > This patch seems to avoid the problem, but is it correct, or is it just
> > papering over a problem elsewhere?
>
> I think the real bug is that CInode::first is less than one of the
> old_inodes keys. Looking at cow_old_inode(), it looks like first should
> always be strictly > than all old_inodes keys. We should probably assert
> as much wherever it is convenient to do so...
>
> In any case, can you see where/how that is happening? If this is a dir
> inode that has been commited and then refetched from the parent dir, that
> probably explains it. For non-multiversion inodes, dn->first ==
> in->first, but not so for these guys, and at first glance I'm not seeing
> it in the CDir::_fetched() code.
This might do the trick?
diff --git a/src/mds/CDir.cc b/src/mds/CDir.cc
index 6761c6f..9034978 100644
--- a/src/mds/CDir.cc
+++ b/src/mds/CDir.cc
@@ -1564,6 +1564,8 @@ void CDir::_fetched(bufferlist &bl, const string& want_dn)
in->xattrs.swap(xattrs);
in->decode_snap_blob(snapbl);
in->old_inodes.swap(old_inodes);
+ if (!in->old_inodes.empty())
+ in->first = in->old_inodes.rbegin()->first + 1;
if (snaps)
in->purge_stale_snap_data(*snaps);
>
> sage
>
> >
> > Subject: mds: Don't modify already-created old_inode
> >
> > In cow_old_inode, do not modify an old_inode that was created before.
> >
> > Signed-off-by: Alexandre Oliva <oliva@xxxxxxxxxxxxxxxxx>
> > ---
> > src/mds/CInode.cc | 14 +++++++++-----
> > 1 files changed, 9 insertions(+), 5 deletions(-)
> >
> > diff --git a/src/mds/CInode.cc b/src/mds/CInode.cc
> > index 53f9e69..fdff86c 100644
> > --- a/src/mds/CInode.cc
> > +++ b/src/mds/CInode.cc
> > @@ -2030,12 +2030,16 @@ old_inode_t& CInode::cow_old_inode(snapid_t follows, bool cow_head)
> > inode_t *pi = cow_head ? get_projected_inode() : get_previous_projected_inode();
> > map<string,bufferptr> *px = cow_head ? get_projected_xattrs() : get_previous_projected_xattrs();
> >
> > + bool found = old_inodes.find(follows) != old_inodes.end();
> > old_inode_t &old = old_inodes[follows];
> > - old.first = first;
> > - old.inode = *pi;
> > - old.xattrs = *px;
> > -
> > - dout(10) << " " << px->size() << " xattrs cowed, " << *px << dendl;
> > +
> > + if (!found) {
> > + old.first = first;
> > + old.inode = *pi;
> > + old.xattrs = *px;
> > +
> > + dout(10) << " " << px->size() << " xattrs cowed, " << *px << dendl;
> > + }
> >
> > old.inode.trim_client_ranges(follows);
> >
> > --
> > 1.7.7.6
> >
> >
> >
> > --
> > Alexandre Oliva, freedom fighter http://FSFLA.org/~lxoliva/
> > You must be the change you wish to see in the world. -- Gandhi
> > Be Free! -- http://FSFLA.org/ FSF Latin America board member
> > Free Software Evangelist Red Hat Brazil Compiler Engineer
> > --
> > To unsubscribe from this list: send the line "unsubscribe ceph-devel" in
> > the body of a message to majordomo@xxxxxxxxxxxxxxx
> > More majordomo info at http://vger.kernel.org/majordomo-info.html
> >
> >
> --
> To unsubscribe from this list: send the line "unsubscribe ceph-devel" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
>
--
To unsubscribe from this list: send the line "unsubscribe ceph-devel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
