ceph: sync before unmounting btrfs devices

There may still be writes in flight, since the osds may not have
shutdown cleanly. This should prevent EBUSY when unmounting.

Fixes: #1997

diff --git a/teuthology/task/ceph.py b/teuthology/task/ceph.py
index 6acb3ccde520427f90a64f77423fd69bf4a61417..af691768df3626c6cabac425ea3947012d79311c 100644 (file)
--- a/teuthology/task/ceph.py
+++ b/teuthology/task/ceph.py
@@ -707,9 +707,11 @@ def cluster(ctx, config):
                 log.info('Unmounting %s on %s' % (dir_, remote))
                 remote.run(
                     args=[
-                        "sudo",
-                        "umount",
-                        "-f",
+                        'sync',
+                        run.Raw('&&'),
+                        'sudo',
+                        'umount',
+                        '-f',
                         dir_
                         ]
                     )