libceph: monc hunt rate is 3s with backoff up to 30s

Unless we are in the process of setting up a client (i.e. connecting to
the monitor cluster for the first time), apply a backoff: every time we
want to reopen a session, increase our timeout by a multiple (currently
2); when we complete the connection, reduce that multipler by 50%.

Mirrors ceph.git commit 794c86fd289bd62a35ed14368fa096c46736e9a2.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/include/linux/ceph/mon_client.h b/include/linux/ceph/mon_client.h
index 8b2d2f0b659e..e230e7ed60d3 100644
--- a/include/linux/ceph/mon_client.h
+++ b/include/linux/ceph/mon_client.h
@@ -72,6 +72,9 @@ struct ceph_mon_client {
         unsigned long sub_renew_sent;
         struct ceph_connection con;
 
+        bool had_a_connection;
+        int hunt_mult; /* [1..CEPH_MONC_HUNT_MAX_MULT] */
+
         /* pending generic requests */
         struct rb_root generic_request_tree;
         int num_generic_requests;