On Tue, Jun 29, 2021 at 6:42 AM <xiubli@xxxxxxxxxx> wrote: > > From: Xiubo Li <xiubli@xxxxxxxxxx> > > Signed-off-by: Xiubo Li <xiubli@xxxxxxxxxx> > --- > fs/ceph/mds_client.c | 29 +++++++++++++++++++++++++++++ > fs/ceph/mds_client.h | 1 + > include/linux/ceph/ceph_fs.h | 1 + > 3 files changed, 31 insertions(+) > > diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c > index 96bef289f58f..2db87a5c68d4 100644 > --- a/fs/ceph/mds_client.c > +++ b/fs/ceph/mds_client.c > @@ -4689,6 +4689,34 @@ static void wait_requests(struct ceph_mds_client *mdsc) > dout("wait_requests done\n"); > } > > +static void send_flush_mdlog(struct ceph_mds_session *s) > +{ > + u64 seq = s->s_seq; > + struct ceph_msg *msg; > + > + /* > + * For the MDS daemons lower than Luminous will crash when it > + * saw this unknown session request. "Pre-luminous MDS crashes when it sees an unknown session request" > + */ > + if (!CEPH_HAVE_FEATURE(s->s_con.peer_features, SERVER_LUMINOUS)) > + return; > + > + dout("send_flush_mdlog to mds%d (%s)s seq %lld\n", Should (%s)s be just (%s)? > + s->s_mds, ceph_session_state_name(s->s_state), seq); > + msg = ceph_create_session_msg(CEPH_SESSION_REQUEST_FLUSH_MDLOG, seq); > + if (!msg) { > + pr_err("failed to send_flush_mdlog to mds%d (%s)s seq %lld\n", Same here and let's avoid function names in error messages. Something like "failed to request mdlog flush ...". > + s->s_mds, ceph_session_state_name(s->s_state), seq); > + } else { > + ceph_con_send(&s->s_con, msg); > + } > +} > + > +void flush_mdlog(struct ceph_mds_client *mdsc) > +{ > + ceph_mdsc_iterate_sessions(mdsc, send_flush_mdlog, true); > +} Is this wrapper really needed? > + > /* > * called before mount is ro, and before dentries are torn down. > * (hmm, does this still race with new lookups?) > @@ -4698,6 +4726,7 @@ void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc) > dout("pre_umount\n"); > mdsc->stopping = 1; > > + flush_mdlog(mdsc); > ceph_mdsc_iterate_sessions(mdsc, lock_unlock_session, false); > ceph_flush_dirty_caps(mdsc); > wait_requests(mdsc); > diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h > index fca2cf427eaf..79d5b8ed62bf 100644 > --- a/fs/ceph/mds_client.h > +++ b/fs/ceph/mds_client.h > @@ -537,6 +537,7 @@ extern int ceph_iterate_session_caps(struct ceph_mds_session *session, > int (*cb)(struct inode *, > struct ceph_cap *, void *), > void *arg); > +extern void flush_mdlog(struct ceph_mds_client *mdsc); > extern void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc); > > static inline void ceph_mdsc_free_path(char *path, int len) > diff --git a/include/linux/ceph/ceph_fs.h b/include/linux/ceph/ceph_fs.h > index 57e5bd63fb7a..ae60696fe40b 100644 > --- a/include/linux/ceph/ceph_fs.h > +++ b/include/linux/ceph/ceph_fs.h > @@ -300,6 +300,7 @@ enum { > CEPH_SESSION_FLUSHMSG_ACK, > CEPH_SESSION_FORCE_RO, > CEPH_SESSION_REJECT, > + CEPH_SESSION_REQUEST_FLUSH_MDLOG, Need to update ceph_session_op_name(). Thanks, Ilya