tipc: simplify group LEAVE sequence

After the changes in the previous commit the group LEAVE sequence
can be simplified.

We now let the arrival of a LEAVE message unconditionally issue a group
DOWN event to the user. When a topology WITHDRAW event is received, the
member, if it still there, is set to state LEAVING, but we only issue a
group DOWN event when the link to the peer node is gone, so that no
LEAVE message is to be expected.

Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 9 insertions, 31 deletions

diff --git a/net/tipc/group.c b/net/tipc/group.c
index e08b7acc7b2d..bdc54be9c07e 100644
--- a/net/tipc/group.c
+++ b/net/tipc/group.c
@@ -749,14 +749,8 @@ void tipc_group_proto_rcv(struct tipc_group *grp, bool *usr_wakeup,
                 list_del_init(&m->list);
                 list_del_init(&m->small_win);
                 *usr_wakeup = true;
-
-                /* Wait until WITHDRAW event is received */
-                if (m->state != MBR_LEAVING) {
-                        tipc_group_decr_active(grp, m);
-                        m->state = MBR_LEAVING;
-                        return;
-                }
-                /* Otherwise deliver member WITHDRAW event */
+                tipc_group_decr_active(grp, m);
+                m->state = MBR_LEAVING;
                 tipc_group_create_event(grp, m, TIPC_WITHDRAWN,
                                         m->bc_syncpt, inputq);
                 return;
@@ -838,7 +832,6 @@ void tipc_group_member_evt(struct tipc_group *grp,
         int event = evt->event;
         struct tipc_member *m;
         struct net *net;
-        bool node_up;
         u32 self;
 
         if (!grp)
@@ -878,30 +871,15 @@ void tipc_group_member_evt(struct tipc_group *grp,
 
                 *usr_wakeup = true;
                 m->usr_pending = false;
-                node_up = tipc_node_is_up(net, node);
-
-                if (node_up) {
-                        /* Hold back event if a LEAVE msg should be expected */
-                        if (m->state != MBR_LEAVING) {
-                                tipc_group_decr_active(grp, m);
-                                m->state = MBR_LEAVING;
-                        } else {
-                                tipc_group_create_event(grp, m, TIPC_WITHDRAWN,
-                                                        m->bc_syncpt, inputq);
-                        }
-                } else {
-                        if (m->state != MBR_LEAVING) {
-                                tipc_group_decr_active(grp, m);
-                                m->state = MBR_LEAVING;
-                                tipc_group_create_event(grp, m, TIPC_WITHDRAWN,
-                                                        m->bc_rcv_nxt, inputq);
-                        } else {
-                                tipc_group_create_event(grp, m, TIPC_WITHDRAWN,
-                                                        m->bc_syncpt, inputq);
-                        }
-                }
+                tipc_group_decr_active(grp, m);
+                m->state = MBR_LEAVING;
                 list_del_init(&m->list);
                 list_del_init(&m->small_win);
+
+                /* Only send event if no LEAVE message can be expected */
+                if (!tipc_node_is_up(net, node))
+                        tipc_group_create_event(grp, m, TIPC_WITHDRAWN,
+                                                m->bc_rcv_nxt, inputq);
         }
         *sk_rcvbuf = tipc_group_rcvbuf_limit(grp);
 }