Commit b9f463d6 authored by Edward Cree's avatar Edward Cree Committed by David S. Miller
Browse files

net: don't bother calling list RX functions on empty lists 



Generally the check should be very cheap, as the sk_buff_head is in cache.

Signed-off-by: default avatarEdward Cree <ecree@solarflare.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 5fa12739

net/core/dev.c

+6 −2
Original line number Diff line number Diff line
@@ -4887,6 +4887,7 @@ static void __netif_receive_skb_list(struct list_head *head) 


			/* Handle the previous sublist */

			list_cut_before(&sublist, head, &skb->list);

			if (!list_empty(&sublist))

				__netif_receive_skb_list_core(&sublist, pfmemalloc);

			pfmemalloc = !pfmemalloc;

			/* See comments in __netif_receive_skb */
@@ -4897,6 +4898,7 @@ static void __netif_receive_skb_list(struct list_head *head) 
		}

	}

	/* Handle the remaining sublist */

	if (!list_empty(head))

		__netif_receive_skb_list_core(head, pfmemalloc);

	/* Restore pflags */

	if (pfmemalloc)
@@ -5058,6 +5060,8 @@ void netif_receive_skb_list(struct list_head *head) 
{

	struct sk_buff *skb;



	if (list_empty(head))

		return;

	list_for_each_entry(skb, head, list)

		trace_netif_receive_skb_list_entry(skb);

	netif_receive_skb_list_internal(head);