[NET]: Bring comments in loopback.c uptodate.

A hint as to why it is safe to use per cpu variables,
and note that we actually can have multiple instances
of the loopback device now.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric W. Biederman 2007-09-27 17:09:39 -07:00 committed by David S. Miller
parent fe242cfd33
commit 9e0db4b12c
1 changed files with 3 additions and 1 deletions

View File

@ -154,6 +154,7 @@ static int loopback_xmit(struct sk_buff *skb, struct net_device *dev)
#endif
dev->last_rx = jiffies;
/* it's OK to use per_cpu_ptr() because BHs are off */
pcpu_lstats = netdev_priv(dev);
lb_stats = per_cpu_ptr(pcpu_lstats, smp_processor_id());
lb_stats->bytes += skb->len;
@ -221,7 +222,8 @@ static void loopback_dev_free(struct net_device *dev)
}
/*
* The loopback device is special. There is only one instance.
* The loopback device is special. There is only one instance
* per network namespace.
*/
static void loopback_setup(struct net_device *dev)
{