[NET]: Disable queueing when carrier is lost.

Some network drivers call netif_stop_queue() when detecting loss of
carrier. This leads to packets being queued up at the qdisc level for
an unbound period of time. In order to prevent this effect, the core
networking stack will now cease to queue packets for any device, that
is operationally down (i.e. the queue is flushed and disabled).

Signed-off-by: Tommy S. Christensen <tommy.christensen@tpack.net>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Tommy S. Christensen 2005-05-03 16:18:52 -07:00 committed by David S. Miller
parent 0f4821e7b9
commit cacaddf57e
2 changed files with 11 additions and 0 deletions

View File

@ -16,6 +16,7 @@
#include <linux/netdevice.h> #include <linux/netdevice.h>
#include <linux/if.h> #include <linux/if.h>
#include <net/sock.h> #include <net/sock.h>
#include <net/pkt_sched.h>
#include <linux/rtnetlink.h> #include <linux/rtnetlink.h>
#include <linux/jiffies.h> #include <linux/jiffies.h>
#include <linux/spinlock.h> #include <linux/spinlock.h>
@ -74,6 +75,12 @@ void linkwatch_run_queue(void)
clear_bit(__LINK_STATE_LINKWATCH_PENDING, &dev->state); clear_bit(__LINK_STATE_LINKWATCH_PENDING, &dev->state);
if (dev->flags & IFF_UP) { if (dev->flags & IFF_UP) {
if (netif_carrier_ok(dev)) {
WARN_ON(dev->qdisc_sleeping == &noop_qdisc);
dev_activate(dev);
} else
dev_deactivate(dev);
netdev_state_change(dev); netdev_state_change(dev);
} }

View File

@ -539,6 +539,10 @@ void dev_activate(struct net_device *dev)
write_unlock_bh(&qdisc_tree_lock); write_unlock_bh(&qdisc_tree_lock);
} }
if (!netif_carrier_ok(dev))
/* Delay activation until next carrier-on event */
return;
spin_lock_bh(&dev->queue_lock); spin_lock_bh(&dev->queue_lock);
rcu_assign_pointer(dev->qdisc, dev->qdisc_sleeping); rcu_assign_pointer(dev->qdisc, dev->qdisc_sleeping);
if (dev->qdisc != &noqueue_qdisc) { if (dev->qdisc != &noqueue_qdisc) {