bridge: implement multicast fast leave

V2: make the toggle per-port

Fast leave allows bridge to immediately stops the multicast
traffic on the port receives IGMP Leave when IGMP snooping is enabled,
no timeouts are observed.

Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index 241743417f498bdc9c8c63fe2500a78f9a4d2126..2391bae4f733caca917d8918b7a32fe01af64e88 100644 (file)
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -1225,6 +1225,27 @@ static void br_multicast_leave_group(struct net_bridge *br,
        if (!mp)
                goto out;
 
+       if (port && port->multicast_fast_leave) {
+               struct net_bridge_port_group __rcu **pp;
+
+               for (pp = &mp->ports;
+                    (p = mlock_dereference(*pp, br)) != NULL;
+                    pp = &p->next) {
+                       if (p->port != port)
+                               continue;
+
+                       rcu_assign_pointer(*pp, p->next);
+                       hlist_del_init(&p->mglist);
+                       del_timer(&p->timer);
+                       call_rcu_bh(&p->rcu, br_multicast_free_pg);
+
+                       if (!mp->ports && !mp->mglist &&
+                           netif_running(br->dev))
+                               mod_timer(&mp->timer, jiffies);
+               }
+               goto out;
+       }
+
        now = jiffies;
        time = now + br->multicast_last_member_count *
                     br->multicast_last_member_interval;

diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index eb9cd42146a5c29cd206e4336436e98598a3e761..cdbf9047a659b1d15582167d3271d048daa62b97 100644 (file)
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -141,6 +141,7 @@ struct net_bridge_port
 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
        u32                             multicast_startup_queries_sent;
        unsigned char                   multicast_router;
+       unsigned char                   multicast_fast_leave;
        struct timer_list               multicast_router_timer;
        struct timer_list               multicast_query_timer;
        struct hlist_head               mglist;

diff --git a/net/bridge/br_sysfs_if.c b/net/bridge/br_sysfs_if.c
index 7ff95ba2198203471eec5e96c89092ce2c5509be..dc484ace0be3314c5e5892bc6646a8406d416a66 100644 (file)
--- a/net/bridge/br_sysfs_if.c
+++ b/net/bridge/br_sysfs_if.c
@@ -172,6 +172,25 @@ static int store_multicast_router(struct net_bridge_port *p,
 }
 static BRPORT_ATTR(multicast_router, S_IRUGO | S_IWUSR, show_multicast_router,
                   store_multicast_router);
+
+static ssize_t show_multicast_fast_leave(struct net_bridge_port *p,
+                                        char *buf)
+{
+       return sprintf(buf, "%d\n", p->multicast_fast_leave);
+}
+
+static int store_multicast_fast_leave(struct net_bridge_port *p,
+                                     unsigned long v)
+{
+       if (p->br->multicast_disabled)
+               return -EINVAL;
+
+       p->multicast_fast_leave = !!v;
+       return 0;
+}
+
+static BRPORT_ATTR(multicast_fast_leave, S_IRUGO | S_IWUSR,
+                  show_multicast_fast_leave, store_multicast_fast_leave);
 #endif
 
 static const struct brport_attribute *brport_attrs[] = {
@@ -195,6 +214,7 @@ static const struct brport_attribute *brport_attrs[] = {
        &brport_attr_root_block,
 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
        &brport_attr_multicast_router,
+       &brport_attr_multicast_fast_leave,
 #endif
        NULL
 };