On Mon, 2022-02-07 at 14:54 +0800, Xiubo Li wrote: > On 2/5/22 11:17 PM, Jeff Layton wrote: > > If we haven't received a reply to an async create request, then we don't > > want to send any cap messages to the MDS for that inode yet. > > > > Just have ceph_check_caps and __kick_flushing_caps return without doing > > anything, and have ceph_write_inode wait for the reply if we were asked > > to wait on the inode writeback. > > > > URL: https://tracker.ceph.com/issues/54107 > > Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx> > > --- > > fs/ceph/caps.c | 14 ++++++++++++++ > > 1 file changed, 14 insertions(+) > > > > diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c > > index e668cdb9c99e..f29e2dbcf8df 100644 > > --- a/fs/ceph/caps.c > > +++ b/fs/ceph/caps.c > > @@ -1916,6 +1916,13 @@ void ceph_check_caps(struct ceph_inode_info *ci, int flags, > > ceph_get_mds_session(session); > > > > spin_lock(&ci->i_ceph_lock); > > + if (ci->i_ceph_flags & CEPH_I_ASYNC_CREATE) { > > + /* Don't send messages until we get async create reply */ > > + spin_unlock(&ci->i_ceph_lock); > > + ceph_put_mds_session(session); > > + return; > > + } > > + > > if (ci->i_ceph_flags & CEPH_I_FLUSH) > > flags |= CHECK_CAPS_FLUSH; > > retry: > > @@ -2410,6 +2417,9 @@ int ceph_write_inode(struct inode *inode, struct writeback_control *wbc) > > dout("write_inode %p wait=%d\n", inode, wait); > > ceph_fscache_unpin_writeback(inode, wbc); > > if (wait) { > > + err = ceph_wait_on_async_create(inode); > > + if (err) > > + return err; > > dirty = try_flush_caps(inode, &flush_tid); > > if (dirty) > > err = wait_event_interruptible(ci->i_cap_wq, > > @@ -2440,6 +2450,10 @@ static void __kick_flushing_caps(struct ceph_mds_client *mdsc, > > u64 first_tid = 0; > > u64 last_snap_flush = 0; > > > > + /* Don't do anything until create reply comes in */ > > + if (ci->i_ceph_flags & CEPH_I_ASYNC_CREATE) > > + return; > > + > > ci->i_ceph_flags &= ~CEPH_I_KICK_FLUSH; > > > > list_for_each_entry_reverse(cf, &ci->i_cap_flush_list, i_list) { > > Is it also possible in case that just after the async unlinking request > is submit and a flush cap request is fired ? Then in MDS side the inode > could be removed from the cache and then the flush cap request comes. > > > Yes. I think that race should be fairly benign though. The MDS might drop the update onto the floor when it can't find the inode, but since the inode is already stale, I don't think we really care... -- Jeff Layton <jlayton@xxxxxxxxxx>
