Commit bec251bc authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

net: no longer stop all TX queues in dev_watchdog() 



There is no reason for stopping all TX queues from dev_watchdog()

Not only this stops feeding the NIC, it also migrates all qdiscs
to be serviced on the cpu calling netif_tx_unlock(), causing
a potential latency artifact.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent dab8fe32

net/sched/sch_generic.c

+5 −3
Original line number Diff line number Diff line
@@ -500,7 +500,7 @@ static void dev_watchdog(struct timer_list *t) 
{

	struct net_device *dev = from_timer(dev, t, watchdog_timer);



	netif_tx_lock(dev);

	spin_lock(&dev->tx_global_lock);

	if (!qdisc_tx_is_noop(dev)) {

		if (netif_device_present(dev) &&

		    netif_running(dev) &&
@@ -523,11 +523,13 @@ static void dev_watchdog(struct timer_list *t) 
				}

			}



			if (some_queue_timedout) {

			if (unlikely(some_queue_timedout)) {

				trace_net_dev_xmit_timeout(dev, i);

				WARN_ONCE(1, KERN_INFO "NETDEV WATCHDOG: %s (%s): transmit queue %u timed out\n",

				       dev->name, netdev_drivername(dev), i);

				netif_freeze_queues(dev);

				dev->netdev_ops->ndo_tx_timeout(dev, i);

				netif_unfreeze_queues(dev);

			}

			if (!mod_timer(&dev->watchdog_timer,

				       round_jiffies(jiffies +
@@ -535,7 +537,7 @@ static void dev_watchdog(struct timer_list *t) 
				dev_hold(dev);

		}

	}

	netif_tx_unlock(dev);

	spin_unlock(&dev->tx_global_lock);



	dev_put(dev);

}