[NETPOLL]: pre-fill skb pool

we could do one thing (see the patch below): i think it would be useful 
to fill up the netlogging skb queue straight at initialization time.  
Especially if netpoll is used for dumping alone, the system might not be 
in a situation to fill up the queue at the point of crash, so better be 
a bit more prepared and keep the pipeline filled.

[ I've modified this to be called earlier - mpm ]
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NMatt Mackall <mpm@selenic.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/core/netpoll.c

@@ -725,6 +725,10 @@ int netpoll_setup(struct netpoll *np)
 		npinfo->rx_np = np;
 		spin_unlock_irqrestore(&npinfo->rx_lock, flags);
 	}
+
+	/* fill up the skb queue */
+	refill_skbs();
+
 	/* last thing to do is link it to the net device structure */
 	ndev->npinfo = npinfo;