tipc: Optimize re-initialization of configuration service

Streamlines the job of re-initializing TIPC's configuration service
when a node's network address is first assigned. Rather than destroying
the configuration server port and then recreating it, TIPC now simply
withdraws the existing {0,<0.0.0>} name publication and creates a new
{0,<Z.C.N>} name publication that identifies the node's network address
to interested subscribers.

Signed-off-by: Allan Stephens <[e-mail]>
Signed-off-by: Paul Gortmaker <[e-mail]>

net/tipc/config.c

···
 	return res;
 }
 
+void tipc_cfg_reinit(void)
+{
+	struct tipc_name_seq seq;
+	int res;
+
+	seq.type = TIPC_CFG_SRV;
+	seq.lower = seq.upper = 0;
+	tipc_withdraw(config_port_ref, TIPC_ZONE_SCOPE, &seq);
+
+	seq.lower = seq.upper = tipc_own_addr;
+	res = tipc_publish(config_port_ref, TIPC_ZONE_SCOPE, &seq);
+	if (res)
+		err("Unable to reinitialize configuration service\n");
+}
+
 void tipc_cfg_stop(void)
 {
 	if (config_port_ref) {

net/tipc/config.h

···
 				int headroom);
 
 int  tipc_cfg_init(void);
+void tipc_cfg_reinit(void);
 void tipc_cfg_stop(void);
 
 #endif

net/tipc/net.c

···
 	char addr_string[16];
 
 	tipc_subscr_stop();
-	tipc_cfg_stop();
 
 	write_lock_bh(&tipc_net_lock);
 	tipc_own_addr = addr;
···
 	write_unlock_bh(&tipc_net_lock);
 
 	tipc_k_signal((Handler)tipc_subscr_start, 0);
-	tipc_k_signal((Handler)tipc_cfg_init, 0);
+	tipc_cfg_reinit();
 
 	info("Started in network mode\n");
 	info("Own node address %s, network identity %u\n",