net: use an atomic_long_t for queue->trans_timeout

tx_timeout_show() assumed dev_watchdog() would stop all
the queues, to fetch queue->trans_timeout under protection
of the queue->_xmit_lock.

As we want to no longer disrupt transmits, we use an
atomic_long_t instead.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: david decotigny <david.decotigny@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2021-11-16 19:29:21 -08:00 committed by David S. Miller
parent b32563b6cc
commit 8160fb43d5
3 changed files with 3 additions and 7 deletions

View File

@ -592,7 +592,7 @@ struct netdev_queue {
* Number of TX timeouts for this queue
* (/sys/class/net/DEV/Q/trans_timeout)
*/
unsigned long trans_timeout;
atomic_long_t trans_timeout;
/* Subordinate device that the queue has been assigned to */
struct net_device *sb_dev;

View File

@ -1201,11 +1201,7 @@ static const struct sysfs_ops netdev_queue_sysfs_ops = {
static ssize_t tx_timeout_show(struct netdev_queue *queue, char *buf)
{
unsigned long trans_timeout;
spin_lock_irq(&queue->_xmit_lock);
trans_timeout = queue->trans_timeout;
spin_unlock_irq(&queue->_xmit_lock);
unsigned long trans_timeout = atomic_long_read(&queue->trans_timeout);
return sprintf(buf, fmt_ulong, trans_timeout);
}

View File

@ -467,7 +467,7 @@ static void dev_watchdog(struct timer_list *t)
time_after(jiffies, (trans_start +
dev->watchdog_timeo))) {
some_queue_timedout = 1;
txq->trans_timeout++;
atomic_long_inc(&txq->trans_timeout);
break;
}
}