linux-stable/net/bridge/br_stp_timer.c
Nikolay Aleksandrov 76b91c32dd bridge: stp: when using userspace stp stop kernel hello and hold timers
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>
2015-07-28 23:33:20 -07:00

178 lines
4.6 KiB
C

/*
* Spanning tree protocol; timer-related code
* Linux ethernet bridge
*
* Authors:
* Lennert Buytenhek <buytenh@gnu.org>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/kernel.h>
#include <linux/times.h>
#include "br_private.h"
#include "br_private_stp.h"
/* called under bridge lock */
static int br_is_designated_for_some_port(const struct net_bridge *br)
{
struct net_bridge_port *p;
list_for_each_entry(p, &br->port_list, list) {
if (p->state != BR_STATE_DISABLED &&
!memcmp(&p->designated_bridge, &br->bridge_id, 8))
return 1;
}
return 0;
}
static void br_hello_timer_expired(unsigned long arg)
{
struct net_bridge *br = (struct net_bridge *)arg;
br_debug(br, "hello timer expired\n");
spin_lock(&br->lock);
if (br->dev->flags & IFF_UP) {
br_config_bpdu_generation(br);
if (br->stp_enabled != BR_USER_STP)
mod_timer(&br->hello_timer,
round_jiffies(jiffies + br->hello_time));
}
spin_unlock(&br->lock);
}
static void br_message_age_timer_expired(unsigned long arg)
{
struct net_bridge_port *p = (struct net_bridge_port *) arg;
struct net_bridge *br = p->br;
const bridge_id *id = &p->designated_bridge;
int was_root;
if (p->state == BR_STATE_DISABLED)
return;
br_info(br, "port %u(%s) neighbor %.2x%.2x.%pM lost\n",
(unsigned int) p->port_no, p->dev->name,
id->prio[0], id->prio[1], &id->addr);
/*
* According to the spec, the message age timer cannot be
* running when we are the root bridge. So.. this was_root
* check is redundant. I'm leaving it in for now, though.
*/
spin_lock(&br->lock);
if (p->state == BR_STATE_DISABLED)
goto unlock;
was_root = br_is_root_bridge(br);
br_become_designated_port(p);
br_configuration_update(br);
br_port_state_selection(br);
if (br_is_root_bridge(br) && !was_root)
br_become_root_bridge(br);
unlock:
spin_unlock(&br->lock);
}
static void br_forward_delay_timer_expired(unsigned long arg)
{
struct net_bridge_port *p = (struct net_bridge_port *) arg;
struct net_bridge *br = p->br;
br_debug(br, "port %u(%s) forward delay timer\n",
(unsigned int) p->port_no, p->dev->name);
spin_lock(&br->lock);
if (p->state == BR_STATE_LISTENING) {
br_set_state(p, BR_STATE_LEARNING);
mod_timer(&p->forward_delay_timer,
jiffies + br->forward_delay);
} else if (p->state == BR_STATE_LEARNING) {
br_set_state(p, BR_STATE_FORWARDING);
if (br_is_designated_for_some_port(br))
br_topology_change_detection(br);
netif_carrier_on(br->dev);
}
br_log_state(p);
rcu_read_lock();
br_ifinfo_notify(RTM_NEWLINK, p);
rcu_read_unlock();
spin_unlock(&br->lock);
}
static void br_tcn_timer_expired(unsigned long arg)
{
struct net_bridge *br = (struct net_bridge *) arg;
br_debug(br, "tcn timer expired\n");
spin_lock(&br->lock);
if (!br_is_root_bridge(br) && (br->dev->flags & IFF_UP)) {
br_transmit_tcn(br);
mod_timer(&br->tcn_timer, jiffies + br->bridge_hello_time);
}
spin_unlock(&br->lock);
}
static void br_topology_change_timer_expired(unsigned long arg)
{
struct net_bridge *br = (struct net_bridge *) arg;
br_debug(br, "topo change timer expired\n");
spin_lock(&br->lock);
br->topology_change_detected = 0;
br->topology_change = 0;
spin_unlock(&br->lock);
}
static void br_hold_timer_expired(unsigned long arg)
{
struct net_bridge_port *p = (struct net_bridge_port *) arg;
br_debug(p->br, "port %u(%s) hold timer expired\n",
(unsigned int) p->port_no, p->dev->name);
spin_lock(&p->br->lock);
if (p->config_pending)
br_transmit_config(p);
spin_unlock(&p->br->lock);
}
void br_stp_timer_init(struct net_bridge *br)
{
setup_timer(&br->hello_timer, br_hello_timer_expired,
(unsigned long) br);
setup_timer(&br->tcn_timer, br_tcn_timer_expired,
(unsigned long) br);
setup_timer(&br->topology_change_timer,
br_topology_change_timer_expired,
(unsigned long) br);
setup_timer(&br->gc_timer, br_fdb_cleanup, (unsigned long) br);
}
void br_stp_port_timer_init(struct net_bridge_port *p)
{
setup_timer(&p->message_age_timer, br_message_age_timer_expired,
(unsigned long) p);
setup_timer(&p->forward_delay_timer, br_forward_delay_timer_expired,
(unsigned long) p);
setup_timer(&p->hold_timer, br_hold_timer_expired,
(unsigned long) p);
}
/* Report ticks left (in USER_HZ) used for API */
unsigned long br_timer_value(const struct timer_list *timer)
{
return timer_pending(timer)
? jiffies_delta_to_clock_t(timer->expires - jiffies) : 0;
}