batman-adv: remove obsolete deleted attribute for gateway node

With rcu, the gateway node deleted attribute is not needed anymore. In fact, it may delay the free of the gateway node and its referenced structures. Therefore remove it altogether and simplify purging as well. Signed-off-by: Simon Wunderlich <simon@open-mesh.com> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>

batman-adv: remove obsolete deleted attribute for gateway node
With rcu, the gateway node deleted attribute is not needed anymore. In fact, it may delay the free of the gateway node and its referenced structures. Therefore remove it altogether and simplify purging as well. Signed-off-by: Simon Wunderlich <simon@open-mesh.com> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
Simon Wunderlich · Antonio Quartulli
1 parent 741aa06bfb
Showing 5 changed files with 14 additions and 41 deletions Side-by-side Diff
net/batman-adv/gateway_client.c
net/batman-adv/gateway_client.h
net/batman-adv/main.c
net/batman-adv/originator.c
net/batman-adv/types.h
@@ -161,9 +161,6 @@
  
 	rcu_read_lock();
 	hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.list, list) {
-		if (gw_node->deleted)
-			continue;
-
 		orig_node = gw_node->orig_node;
 		router = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
 		if (!router)
@@ -473,9 +470,6 @@
 		if (gw_node_tmp->orig_node != orig_node)
 			continue;
  
-		if (gw_node_tmp->deleted)
-			continue;
-
 		if (!atomic_inc_not_zero(&gw_node_tmp->refcount))
 			continue;
  
  
@@ -525,9 +519,7 @@
 	gw_node->bandwidth_down = ntohl(gateway->bandwidth_down);
 	gw_node->bandwidth_up = ntohl(gateway->bandwidth_up);
  
-	gw_node->deleted = 0;
 	if (ntohl(gateway->bandwidth_down) == 0) {
-		gw_node->deleted = jiffies;
 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 			   "Gateway %pM removed from gateway list\n",
 			   orig_node->orig);
  
  
@@ -535,14 +527,21 @@
 		/* Note: We don't need a NULL check here, since curr_gw never
 		 * gets dereferenced.
 		 */
+		spin_lock_bh(&bat_priv->gw.list_lock);
+		hlist_del_init_rcu(&gw_node->list);
+		spin_unlock_bh(&bat_priv->gw.list_lock);
+
+		batadv_gw_node_free_ref(gw_node);
+
 		curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
 		if (gw_node == curr_gw)
 			batadv_gw_reselect(bat_priv);
+
+		if (curr_gw)
+			batadv_gw_node_free_ref(curr_gw);
 	}
  
 out:
-	if (curr_gw)
-		batadv_gw_node_free_ref(curr_gw);
 	if (gw_node)
 		batadv_gw_node_free_ref(gw_node);
 }
  
  
  
  
  
  
  
  
@@ -558,39 +557,19 @@
 	batadv_gw_node_update(bat_priv, orig_node, &gateway);
 }
  
-void batadv_gw_node_purge(struct batadv_priv *bat_priv)
+void batadv_gw_node_free(struct batadv_priv *bat_priv)
 {
-	struct batadv_gw_node *gw_node, *curr_gw;
+	struct batadv_gw_node *gw_node;
 	struct hlist_node *node_tmp;
-	unsigned long timeout = msecs_to_jiffies(2 * BATADV_PURGE_TIMEOUT);
-	int do_reselect = 0;
  
-	curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
-
 	spin_lock_bh(&bat_priv->gw.list_lock);
-
 	hlist_for_each_entry_safe(gw_node, node_tmp,
 				  &bat_priv->gw.list, list) {
-		if (((!gw_node->deleted) ||
-		     (time_before(jiffies, gw_node->deleted + timeout))) &&
-		    atomic_read(&bat_priv->mesh_state) == BATADV_MESH_ACTIVE)
-			continue;
  
-		if (curr_gw == gw_node)
-			do_reselect = 1;
-
-		hlist_del_rcu(&gw_node->list);
+		hlist_del_init_rcu(&gw_node->list);
 		batadv_gw_node_free_ref(gw_node);
 	}
-
 	spin_unlock_bh(&bat_priv->gw.list_lock);
-
-	/* gw_reselect() needs to acquire the gw_list_lock */
-	if (do_reselect)
-		batadv_gw_reselect(bat_priv);
-
-	if (curr_gw)
-		batadv_gw_node_free_ref(curr_gw);
 }
  
 /* fails if orig_node has no router */
@@ -654,9 +633,6 @@
  
 	rcu_read_lock();
 	hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.list, list) {
-		if (gw_node->deleted)
-			continue;
-
 		/* fails if orig_node has no router */
 		if (batadv_write_buffer_text(bat_priv, seq, gw_node) < 0)
 			continue;
@@ -38,7 +38,7 @@
 			   struct batadv_tvlv_gateway_data *gateway);
 void batadv_gw_node_delete(struct batadv_priv *bat_priv,
 			   struct batadv_orig_node *orig_node);
-void batadv_gw_node_purge(struct batadv_priv *bat_priv);
+void batadv_gw_node_free(struct batadv_priv *bat_priv);
 int batadv_gw_client_seq_print_text(struct seq_file *seq, void *offset);
 bool batadv_gw_out_of_range(struct batadv_priv *bat_priv, struct sk_buff *skb);
 enum batadv_dhcp_recipient
@@ -199,7 +199,7 @@
  
 	batadv_purge_outstanding_packets(bat_priv, NULL);
  
-	batadv_gw_node_purge(bat_priv);
+	batadv_gw_node_free(bat_priv);
 	batadv_nc_mesh_free(bat_priv);
 	batadv_dat_free(bat_priv);
 	batadv_bla_free(bat_priv);
@@ -1028,7 +1028,6 @@
 		spin_unlock_bh(list_lock);
 	}
  
-	batadv_gw_node_purge(bat_priv);
 	batadv_gw_election(bat_priv);
 }
  
@@ -328,7 +328,6 @@
  * @orig_node: pointer to corresponding orig node
  * @bandwidth_down: advertised uplink download bandwidth
  * @bandwidth_up: advertised uplink upload bandwidth
- * @deleted: this struct is scheduled for deletion
  * @refcount: number of contexts the object is used
  * @rcu: struct used for freeing in an RCU-safe manner
  */
@@ -337,7 +336,6 @@
 	struct batadv_orig_node *orig_node;
 	u32 bandwidth_down;
 	u32 bandwidth_up;
-	unsigned long deleted;
 	atomic_t refcount;
 	struct rcu_head rcu;
 };
...	...	@@ -161,9 +161,6 @@
161	161
162	162	rcu_read_lock();
163	163	hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.list, list) {
164		- if (gw_node->deleted)
165		- continue;
166		-
167	164	orig_node = gw_node->orig_node;
168	165	router = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
169	166	if (!router)
...	...	@@ -473,9 +470,6 @@
473	470	if (gw_node_tmp->orig_node != orig_node)
474	471	continue;
475	472
476		- if (gw_node_tmp->deleted)
477		- continue;
478		-
479	473	if (!atomic_inc_not_zero(&gw_node_tmp->refcount))
480	474	continue;
481	475
482	476
...	...	@@ -525,9 +519,7 @@
525	519	gw_node->bandwidth_down = ntohl(gateway->bandwidth_down);
526	520	gw_node->bandwidth_up = ntohl(gateway->bandwidth_up);
527	521
528		- gw_node->deleted = 0;
529	522	if (ntohl(gateway->bandwidth_down) == 0) {
530		- gw_node->deleted = jiffies;
531	523	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
532	524	"Gateway %pM removed from gateway list\n",
533	525	orig_node->orig);
534	526
535	527
...	...	@@ -535,14 +527,21 @@
535	527	/* Note: We don't need a NULL check here, since curr_gw never
536	528	* gets dereferenced.
537	529	*/
	530	+ spin_lock_bh(&bat_priv->gw.list_lock);
	531	+ hlist_del_init_rcu(&gw_node->list);
	532	+ spin_unlock_bh(&bat_priv->gw.list_lock);
	533	+
	534	+ batadv_gw_node_free_ref(gw_node);
	535	+
538	536	curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
539	537	if (gw_node == curr_gw)
540	538	batadv_gw_reselect(bat_priv);
	539	+
	540	+ if (curr_gw)
	541	+ batadv_gw_node_free_ref(curr_gw);
541	542	}
542	543
543	544	out:
544		- if (curr_gw)
545		- batadv_gw_node_free_ref(curr_gw);
546	545	if (gw_node)
547	546	batadv_gw_node_free_ref(gw_node);
548	547	}
549	548
550	549
551	550
552	551
553	552
554	553
555	554
556	555
...	...	@@ -558,39 +557,19 @@
558	557	batadv_gw_node_update(bat_priv, orig_node, &gateway);
559	558	}
560	559
561		-void batadv_gw_node_purge(struct batadv_priv *bat_priv)
	560	+void batadv_gw_node_free(struct batadv_priv *bat_priv)
562	561	{
563		- struct batadv_gw_node gw_node, curr_gw;
	562	+ struct batadv_gw_node *gw_node;
564	563	struct hlist_node *node_tmp;
565		- unsigned long timeout = msecs_to_jiffies(2 * BATADV_PURGE_TIMEOUT);
566		- int do_reselect = 0;
567	564
568		- curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
569		-
570	565	spin_lock_bh(&bat_priv->gw.list_lock);
571		-
572	566	hlist_for_each_entry_safe(gw_node, node_tmp,
573	567	&bat_priv->gw.list, list) {
574		- if (((!gw_node->deleted) \|\|
575		- (time_before(jiffies, gw_node->deleted + timeout))) &&
576		- atomic_read(&bat_priv->mesh_state) == BATADV_MESH_ACTIVE)
577		- continue;
578	568
579		- if (curr_gw == gw_node)
580		- do_reselect = 1;
581		-
582		- hlist_del_rcu(&gw_node->list);
	569	+ hlist_del_init_rcu(&gw_node->list);
583	570	batadv_gw_node_free_ref(gw_node);
584	571	}
585		-
586	572	spin_unlock_bh(&bat_priv->gw.list_lock);
587		-
588		- /* gw_reselect() needs to acquire the gw_list_lock */
589		- if (do_reselect)
590		- batadv_gw_reselect(bat_priv);
591		-
592		- if (curr_gw)
593		- batadv_gw_node_free_ref(curr_gw);
594	573	}
595	574
596	575	/* fails if orig_node has no router */
...	...	@@ -654,9 +633,6 @@
654	633
655	634	rcu_read_lock();
656	635	hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.list, list) {
657		- if (gw_node->deleted)
658		- continue;
659		-
660	636	/* fails if orig_node has no router */
661	637	if (batadv_write_buffer_text(bat_priv, seq, gw_node) < 0)
662	638	continue;
...	...	@@ -38,7 +38,7 @@
38	38	struct batadv_tvlv_gateway_data *gateway);
39	39	void batadv_gw_node_delete(struct batadv_priv *bat_priv,
40	40	struct batadv_orig_node *orig_node);
41		-void batadv_gw_node_purge(struct batadv_priv *bat_priv);
	41	+void batadv_gw_node_free(struct batadv_priv *bat_priv);
42	42	int batadv_gw_client_seq_print_text(struct seq_file seq, void offset);
43	43	bool batadv_gw_out_of_range(struct batadv_priv bat_priv, struct sk_buff skb);
44	44	enum batadv_dhcp_recipient
...	...	@@ -199,7 +199,7 @@
199	199
200	200	batadv_purge_outstanding_packets(bat_priv, NULL);
201	201
202		- batadv_gw_node_purge(bat_priv);
	202	+ batadv_gw_node_free(bat_priv);
203	203	batadv_nc_mesh_free(bat_priv);
204	204	batadv_dat_free(bat_priv);
205	205	batadv_bla_free(bat_priv);
...	...	@@ -1028,7 +1028,6 @@
1028	1028	spin_unlock_bh(list_lock);
1029	1029	}
1030	1030
1031		- batadv_gw_node_purge(bat_priv);
1032	1031	batadv_gw_election(bat_priv);
1033	1032	}
1034	1033
...	...	@@ -328,7 +328,6 @@
328	328	* @orig_node: pointer to corresponding orig node
329	329	* @bandwidth_down: advertised uplink download bandwidth
330	330	* @bandwidth_up: advertised uplink upload bandwidth
331		- * @deleted: this struct is scheduled for deletion
332	331	* @refcount: number of contexts the object is used
333	332	* @rcu: struct used for freeing in an RCU-safe manner
334	333	*/
...	...	@@ -337,7 +336,6 @@
337	336	struct batadv_orig_node *orig_node;
338	337	u32 bandwidth_down;
339	338	u32 bandwidth_up;
340		- unsigned long deleted;
341	339	atomic_t refcount;
342	340	struct rcu_head rcu;
343	341	};