[NET] ethernet: optimize memcpy and memset

The ethernet header management only needs to handle a fixed
size address (6 bytes). If the memcpy/memset are changed to
be passed a constant length, then compiler can optimize for
this case (and if it is smart eliminate string instructions).

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Stephen Hemminger 2007-08-24 22:35:44 -07:00 committed by David S. Miller
parent fd21150a0f
commit 23f1f4eff8

View file

@ -91,10 +91,10 @@ int eth_header(struct sk_buff *skb, struct net_device *dev, unsigned short type,
if (!saddr) if (!saddr)
saddr = dev->dev_addr; saddr = dev->dev_addr;
memcpy(eth->h_source, saddr, dev->addr_len); memcpy(eth->h_source, saddr, ETH_ALEN);
if (daddr) { if (daddr) {
memcpy(eth->h_dest, daddr, dev->addr_len); memcpy(eth->h_dest, daddr, ETH_ALEN);
return ETH_HLEN; return ETH_HLEN;
} }
@ -103,7 +103,7 @@ int eth_header(struct sk_buff *skb, struct net_device *dev, unsigned short type,
*/ */
if (dev->flags & (IFF_LOOPBACK | IFF_NOARP)) { if (dev->flags & (IFF_LOOPBACK | IFF_NOARP)) {
memset(eth->h_dest, 0, dev->addr_len); memset(eth->h_dest, 0, ETH_ALEN);
return ETH_HLEN; return ETH_HLEN;
} }
@ -135,7 +135,7 @@ int eth_rebuild_header(struct sk_buff *skb)
"%s: unable to resolve type %X addresses.\n", "%s: unable to resolve type %X addresses.\n",
dev->name, (int)eth->h_proto); dev->name, (int)eth->h_proto);
memcpy(eth->h_source, dev->dev_addr, dev->addr_len); memcpy(eth->h_source, dev->dev_addr, ETH_ALEN);
break; break;
} }
@ -233,8 +233,8 @@ int eth_header_cache(struct neighbour *neigh, struct hh_cache *hh)
return -1; return -1;
eth->h_proto = type; eth->h_proto = type;
memcpy(eth->h_source, dev->dev_addr, dev->addr_len); memcpy(eth->h_source, dev->dev_addr, ETH_ALEN);
memcpy(eth->h_dest, neigh->ha, dev->addr_len); memcpy(eth->h_dest, neigh->ha, ETH_ALEN);
hh->hh_len = ETH_HLEN; hh->hh_len = ETH_HLEN;
return 0; return 0;
} }
@ -251,7 +251,7 @@ void eth_header_cache_update(struct hh_cache *hh, struct net_device *dev,
unsigned char *haddr) unsigned char *haddr)
{ {
memcpy(((u8 *) hh->hh_data) + HH_DATA_OFF(sizeof(struct ethhdr)), memcpy(((u8 *) hh->hh_data) + HH_DATA_OFF(sizeof(struct ethhdr)),
haddr, dev->addr_len); haddr, ETH_ALEN);
} }
/** /**
@ -271,7 +271,7 @@ static int eth_mac_addr(struct net_device *dev, void *p)
return -EBUSY; return -EBUSY;
if (!is_valid_ether_addr(addr->sa_data)) if (!is_valid_ether_addr(addr->sa_data))
return -EADDRNOTAVAIL; return -EADDRNOTAVAIL;
memcpy(dev->dev_addr, addr->sa_data, dev->addr_len); memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
return 0; return 0;
} }