ceph: fix multiple mds session shutdown
The use of a completion when waiting for session shutdown during umount is
inappropriate, given the complexity of the condition. For multiple MDS's,
this resulted in the umount thread spinning, often preventing the session
close message from being processed in some cases.
Switch to a waitqueue and defined a condition helper. This cleans things
up nicely.
Signed-off-by: Sage Weil <sage@newdream.net>
diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h
index ab7e89f..c98267c 100644
--- a/fs/ceph/mds_client.h
+++ b/fs/ceph/mds_client.h
@@ -234,7 +234,8 @@
struct mutex mutex; /* all nested structures */
struct ceph_mdsmap *mdsmap;
- struct completion safe_umount_waiters, session_close_waiters;
+ struct completion safe_umount_waiters;
+ wait_queue_head_t session_close_wq;
struct list_head waiting_for_map;
struct ceph_mds_session **sessions; /* NULL for mds if no session */