summaryrefslogtreecommitdiffstats
path: root/net/ethernet/eth.c
diff options
context:
space:
mode:
authorstephen hemminger <stephen@networkplumber.org>2013-09-28 02:21:27 +0200
committerDavid S. Miller <davem@davemloft.net>2013-10-01 06:52:53 +0200
commit56d7b53f47e7c9a0ab1c6289f2669a8d3a65cf17 (patch)
treed07ed00e0c65e64622b53182ad063e7cd51675c4 /net/ethernet/eth.c
parentethernet: cleanup eth_type_trans (diff)
downloadlinux-56d7b53f47e7c9a0ab1c6289f2669a8d3a65cf17.tar.xz
linux-56d7b53f47e7c9a0ab1c6289f2669a8d3a65cf17.zip
ethernet: use likely() for common Ethernet encap
Mark code path's likely/unlikely based on most common usage. * Very few devices use dsa tags. * Most traffic is Ethernet (not 802.2) * No sane person uses trailer type or Novell encapsulation Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ethernet/eth.c')
-rw-r--r--net/ethernet/eth.c9
1 files changed, 5 insertions, 4 deletions
diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c
index f777e17d28c8..8f032bae60ad 100644
--- a/net/ethernet/eth.c
+++ b/net/ethernet/eth.c
@@ -179,12 +179,13 @@ __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev)
* variants has been configured on the receiving interface,
* and if so, set skb->protocol without looking at the packet.
*/
- if (netdev_uses_dsa_tags(dev))
+ if (unlikely(netdev_uses_dsa_tags(dev)))
return htons(ETH_P_DSA);
- if (netdev_uses_trailer_tags(dev))
+
+ if (unlikely(netdev_uses_trailer_tags(dev)))
return htons(ETH_P_TRAILER);
- if (ntohs(eth->h_proto) >= ETH_P_802_3_MIN)
+ if (likely(ntohs(eth->h_proto) >= ETH_P_802_3_MIN))
return eth->h_proto;
/*
@@ -193,7 +194,7 @@ __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev)
* layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This
* won't work for fault tolerant netware but does for the rest.
*/
- if (skb->len >= 2 && *(unsigned short *)(skb->data) == 0xFFFF)
+ if (unlikely(skb->len >= 2 && *(unsigned short *)(skb->data) == 0xFFFF))
return htons(ETH_P_802_3);
/*