The last_rx field in the loopback driver is updated on every xmit but
is not used otherwise. Accesses to ->last_rx cause unecessary traffic on the
interlink for NUMA systems which limits the performance of the loopback device.

The comment given at include/linux/netdevice.h says that last_rx may be
used for future network-power-down code, which is likely not relevant
for the loopback device (please let me know if it is otherwise ..).

Signed-off-by: Niraj Kumar <[EMAIL PROTECTED]>
Signed-off-by: Christoph Lameter <[EMAIL PROTECTED]>
Signed-off-by: Shai Fultheim <[EMAIL PROTECTED]>

--- linux-2.6.9.clean/drivers/net/loopback.c    2005-02-28 21:54:20.000000000 
-0800
+++ linux-2.6.9.clean-loop/drivers/net/loopback.c       2005-03-03 
22:59:34.068607608 -0800
@@ -144,8 +144,6 @@ static int loopback_xmit(struct sk_buff
                return 0;
        }

-       dev->last_rx = jiffies;
-
        lb_stats = &per_cpu(loopback_stats, get_cpu());
        lb_stats->rx_bytes += skb->len;
        lb_stats->tx_bytes += skb->len;
-
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