bridge: stp: when using userspace stp stop kernel hello and hold timers
authorNikolay Aleksandrov <razor@blackwall.org>
Thu, 23 Jul 2015 18:01:05 +0000 (11:01 -0700)
committerDavid S. Miller <davem@davemloft.net>
Wed, 29 Jul 2015 06:33:20 +0000 (23:33 -0700)
These should be handled only by the respective STP which is in control.
They become problematic for devices with limited resources with many
ports because the hold_timer is per port and fires each second and the
hello timer fires each 2 seconds even though it's global. While in
user-space STP mode these timers are completely unnecessary so it's better
to keep them off.
Also ensure that when the bridge is up these timers are started only when
running with kernel STP.

Signed-off-by: Satish Ashok <sashok@cumulusnetworks.com>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/bridge/br_stp.c
net/bridge/br_stp_if.c
net/bridge/br_stp_timer.c

index b4b6dab9c2859730d3ba9b5bc17f8302ddca6510..ed74ffaa851ff43d08c3edb4a158ab21af27e1a3 100644 (file)
@@ -209,8 +209,9 @@ void br_transmit_config(struct net_bridge_port *p)
                br_send_config_bpdu(p, &bpdu);
                p->topology_change_ack = 0;
                p->config_pending = 0;
-               mod_timer(&p->hold_timer,
-                         round_jiffies(jiffies + BR_HOLD_TIME));
+               if (p->br->stp_enabled == BR_KERNEL_STP)
+                       mod_timer(&p->hold_timer,
+                                 round_jiffies(jiffies + BR_HOLD_TIME));
        }
 }
 
index a2730e7196cd7080b96a441f5cc40591320862e5..4ca449a161320f7ef1c6f4864940e8557a7d18e3 100644 (file)
@@ -48,7 +48,8 @@ void br_stp_enable_bridge(struct net_bridge *br)
        struct net_bridge_port *p;
 
        spin_lock_bh(&br->lock);
-       mod_timer(&br->hello_timer, jiffies + br->hello_time);
+       if (br->stp_enabled == BR_KERNEL_STP)
+               mod_timer(&br->hello_timer, jiffies + br->hello_time);
        mod_timer(&br->gc_timer, jiffies + HZ/10);
 
        br_config_bpdu_generation(br);
@@ -127,6 +128,7 @@ static void br_stp_start(struct net_bridge *br)
        int r;
        char *argv[] = { BR_STP_PROG, br->dev->name, "start", NULL };
        char *envp[] = { NULL };
+       struct net_bridge_port *p;
 
        r = call_usermodehelper(BR_STP_PROG, argv, envp, UMH_WAIT_PROC);
 
@@ -140,6 +142,10 @@ static void br_stp_start(struct net_bridge *br)
        if (r == 0) {
                br->stp_enabled = BR_USER_STP;
                br_debug(br, "userspace STP started\n");
+               /* Stop hello and hold timers */
+               del_timer(&br->hello_timer);
+               list_for_each_entry(p, &br->port_list, list)
+                       del_timer(&p->hold_timer);
        } else {
                br->stp_enabled = BR_KERNEL_STP;
                br_debug(br, "using kernel STP\n");
@@ -156,12 +162,17 @@ static void br_stp_stop(struct net_bridge *br)
        int r;
        char *argv[] = { BR_STP_PROG, br->dev->name, "stop", NULL };
        char *envp[] = { NULL };
+       struct net_bridge_port *p;
 
        if (br->stp_enabled == BR_USER_STP) {
                r = call_usermodehelper(BR_STP_PROG, argv, envp, UMH_WAIT_PROC);
                br_info(br, "userspace STP stopped, return code %d\n", r);
 
                /* To start timers on any ports left in blocking */
+               mod_timer(&br->hello_timer, jiffies + br->hello_time);
+               list_for_each_entry(p, &br->port_list, list)
+                       mod_timer(&p->hold_timer,
+                                 round_jiffies(jiffies + BR_HOLD_TIME));
                spin_lock_bh(&br->lock);
                br_port_state_selection(br);
                spin_unlock_bh(&br->lock);
index 7caf7fae2d5b8aa369b924e1c87a47c343fb8954..5f0f5af0ec35bf8c216935713a9d5f803456e1ab 100644 (file)
@@ -40,7 +40,9 @@ static void br_hello_timer_expired(unsigned long arg)
        if (br->dev->flags & IFF_UP) {
                br_config_bpdu_generation(br);
 
-               mod_timer(&br->hello_timer, round_jiffies(jiffies + br->hello_time));
+               if (br->stp_enabled != BR_USER_STP)
+                       mod_timer(&br->hello_timer,
+                                 round_jiffies(jiffies + br->hello_time));
        }
        spin_unlock(&br->lock);
 }