bridge: mrp: Use hlist_head instead of list_head for mrp

Replace list_head with hlist_head for MRP list under the bridge.
There is no need for a circular list when a linear list will work.
This will also decrease the size of 'struct net_bridge'.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Link: https://lore.kernel.org/r/20201106215049.1448185-1-horatiu.vultur@microchip.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

net/bridge/br_device.c

@@ -456,7 +456,7 @@ void br_dev_setup(struct net_device *dev)
 	INIT_HLIST_HEAD(&br->fdb_list);
 	INIT_HLIST_HEAD(&br->frame_type_list);
 #if IS_ENABLED(CONFIG_BRIDGE_MRP)
-	INIT_LIST_HEAD(&br->mrp_list);
+	INIT_HLIST_HEAD(&br->mrp_list);
 #endif
 #if IS_ENABLED(CONFIG_BRIDGE_CFM)
 	INIT_HLIST_HEAD(&br->mep_list);

net/bridge/br_mrp.c

@@ -54,8 +54,8 @@ static struct br_mrp *br_mrp_find_id(struct net_bridge *br, u32 ring_id)
 	struct br_mrp *res = NULL;
 	struct br_mrp *mrp;
 
-	list_for_each_entry_rcu(mrp, &br->mrp_list, list,
-				lockdep_rtnl_is_held()) {
+	hlist_for_each_entry_rcu(mrp, &br->mrp_list, list,
+				 lockdep_rtnl_is_held()) {
 		if (mrp->ring_id == ring_id) {
 			res = mrp;
 			break;
@@ -70,8 +70,8 @@ static struct br_mrp *br_mrp_find_in_id(struct net_bridge *br, u32 in_id)
 	struct br_mrp *res = NULL;
 	struct br_mrp *mrp;
 
-	list_for_each_entry_rcu(mrp, &br->mrp_list, list,
-				lockdep_rtnl_is_held()) {
+	hlist_for_each_entry_rcu(mrp, &br->mrp_list, list,
+				 lockdep_rtnl_is_held()) {
 		if (mrp->in_id == in_id) {
 			res = mrp;
 			break;
@@ -85,8 +85,8 @@ static bool br_mrp_unique_ifindex(struct net_bridge *br, u32 ifindex)
 {
 	struct br_mrp *mrp;
 
-	list_for_each_entry_rcu(mrp, &br->mrp_list, list,
-				lockdep_rtnl_is_held()) {
+	hlist_for_each_entry_rcu(mrp, &br->mrp_list, list,
+				 lockdep_rtnl_is_held()) {
 		struct net_bridge_port *p;
 
 		p = rtnl_dereference(mrp->p_port);
@@ -111,8 +111,8 @@ static struct br_mrp *br_mrp_find_port(struct net_bridge *br,
 	struct br_mrp *res = NULL;
 	struct br_mrp *mrp;
 
-	list_for_each_entry_rcu(mrp, &br->mrp_list, list,
-				lockdep_rtnl_is_held()) {
+	hlist_for_each_entry_rcu(mrp, &br->mrp_list, list,
+				 lockdep_rtnl_is_held()) {
 		if (rcu_access_pointer(mrp->p_port) == p ||
 		    rcu_access_pointer(mrp->s_port) == p ||
 		    rcu_access_pointer(mrp->i_port) == p) {
@@ -450,10 +450,10 @@ static void br_mrp_del_impl(struct net_bridge *br, struct br_mrp *mrp)
 		rcu_assign_pointer(mrp->i_port, NULL);
 	}
 
-	list_del_rcu(&mrp->list);
+	hlist_del_rcu(&mrp->list);
 	kfree_rcu(mrp, rcu);
 
-	if (list_empty(&br->mrp_list))
+	if (hlist_empty(&br->mrp_list))
 		br_del_frame(br, &mrp_frame_type);
 }
 
@@ -503,12 +503,12 @@ int br_mrp_add(struct net_bridge *br, struct br_mrp_instance *instance)
 	spin_unlock_bh(&br->lock);
 	rcu_assign_pointer(mrp->s_port, p);
 
-	if (list_empty(&br->mrp_list))
+	if (hlist_empty(&br->mrp_list))
 		br_add_frame(br, &mrp_frame_type);
 
 	INIT_DELAYED_WORK(&mrp->test_work, br_mrp_test_work_expired);
 	INIT_DELAYED_WORK(&mrp->in_test_work, br_mrp_in_test_work_expired);
-	list_add_tail_rcu(&mrp->list, &br->mrp_list);
+	hlist_add_tail_rcu(&mrp->list, &br->mrp_list);
 
 	err = br_mrp_switchdev_add(br, mrp);
 	if (err)
@@ -1198,5 +1198,5 @@ static int br_mrp_process(struct net_bridge_port *p, struct sk_buff *skb)
 
 bool br_mrp_enabled(struct net_bridge *br)
 {
-	return !list_empty(&br->mrp_list);
+	return !hlist_empty(&br->mrp_list);
 }

net/bridge/br_mrp_netlink.c

@@ -453,7 +453,7 @@ int br_mrp_fill_info(struct sk_buff *skb, struct net_bridge *br)
 	if (!mrp_tb)
 		return -EMSGSIZE;
 
-	list_for_each_entry_rcu(mrp, &br->mrp_list, list) {
+	hlist_for_each_entry_rcu(mrp, &br->mrp_list, list) {
 		struct net_bridge_port *p;
 
 		tb = nla_nest_start_noflag(skb, IFLA_BRIDGE_MRP_INFO);

net/bridge/br_private.h

@@ -482,7 +482,7 @@ struct net_bridge {
 	struct hlist_head		fdb_list;
 
 #if IS_ENABLED(CONFIG_BRIDGE_MRP)
-	struct list_head		mrp_list;
+	struct hlist_head		mrp_list;
 #endif
 #if IS_ENABLED(CONFIG_BRIDGE_CFM)
 	struct hlist_head		mep_list;

net/bridge/br_private_mrp.h

@@ -8,7 +8,7 @@
 
 struct br_mrp {
 	/* list of mrp instances */
-	struct list_head		list;
+	struct hlist_node		list;
 
 	struct net_bridge_port __rcu	*p_port;
 	struct net_bridge_port __rcu	*s_port;