ctdb-daemon: Simplify ctdb_control_modflags()

Now that there are separate disable/enable controls used by the ctdb
tool this control can ignore any flag updates for the current nodes.
These only come from the recovery master, which depends on being able
to fetch flags for all nodes.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=14784
Signed-off-by: Martin Schwenke <martin@meltin.net>
Reviewed-by: Amitay Isaacs <amitay@gmail.com>

diff --git a/ctdb/server/ctdb_monitor.c b/ctdb/server/ctdb_monitor.c
index 67b99c61e8ff13b8003d5bd9608e6d9bd4331dab..913e2721f98c47609fb96194d26966183cd86eb2 100644 (file)
--- a/ctdb/server/ctdb_monitor.c
+++ b/ctdb/server/ctdb_monitor.c
@@ -455,34 +455,35 @@ int32_t ctdb_control_modflags(struct ctdb_context *ctdb, TDB_DATA indata)
        struct ctdb_node *node;
        uint32_t old_flags;
 
-       if (c->pnn >= ctdb->num_nodes) {
-               DEBUG(DEBUG_ERR,(__location__ " Node %d is invalid, num_nodes :%d\n", c->pnn, ctdb->num_nodes));
-               return -1;
+       /*
+        * Don't let other nodes override the current node's flags.
+        * The recovery master fetches flags from this node so there's
+        * no need to push them back.  Doing so is racy.
+        */
+       if (c->pnn == ctdb->pnn) {
+               DBG_DEBUG("Ignoring flag changes for current node\n");
+               return 0;
        }
 
-       node         = ctdb->nodes[c->pnn];
-       old_flags    = node->flags;
-       if (c->pnn != ctdb->pnn) {
-               c->old_flags  = node->flags;
+       node = ctdb_find_node(ctdb, c->pnn);
+       if (node == NULL) {
+               DBG_ERR("Node %u is invalid\n", c->pnn);
+               return -1;
        }
-       node->flags   = c->new_flags & ~NODE_FLAGS_DISCONNECTED;
-       node->flags  |= (c->old_flags & NODE_FLAGS_DISCONNECTED);
 
-       /* we don't let other nodes modify our STOPPED status */
-       if (c->pnn == ctdb->pnn) {
-               node->flags &= ~NODE_FLAGS_STOPPED;
-               if (old_flags & NODE_FLAGS_STOPPED) {
-                       node->flags |= NODE_FLAGS_STOPPED;
-               }
-       }
+       /*
+        * Remember the old flags.  We don't care what some other node
+        * thought the old flags were - that's irrelevant.
+        */
+       old_flags = node->flags;
 
-       /* we don't let other nodes modify our BANNED status */
-       if (c->pnn == ctdb->pnn) {
-               node->flags &= ~NODE_FLAGS_BANNED;
-               if (old_flags & NODE_FLAGS_BANNED) {
-                       node->flags |= NODE_FLAGS_BANNED;
-               }
-       }
+       /*
+        * This node tracks nodes it is connected to, so don't let
+        * another node override this
+        */
+       node->flags =
+               (old_flags & NODE_FLAGS_DISCONNECTED) |
+               (c->new_flags & ~NODE_FLAGS_DISCONNECTED);
 
        if (node->flags == old_flags) {
                return 0;