[SK_BUFF]: Convert skb->tail to sk_buff_data_t

So that it is also an offset from skb->head, reduces its size from 8 to 4 bytes
on 64bit architectures, allowing us to combine the 4 bytes hole left by the
layer headers conversion, reducing struct sk_buff size to 256 bytes, i.e. 4
64byte cachelines, and since the sk_buff slab cache is SLAB_HWCACHE_ALIGN...
:-)

Many calculations that previously required that skb->{transport,network,
mac}_header be first converted to a pointer now can be done directly, being
meaningful as offsets or pointers.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/net/pcmcia/nmclan_cs.c b/drivers/net/pcmcia/nmclan_cs.c
index ec0af65cd5d7..73da611fd536 100644
--- a/drivers/net/pcmcia/nmclan_cs.c
+++ b/drivers/net/pcmcia/nmclan_cs.c
@@ -1185,7 +1185,7 @@ static int mace_rx(struct net_device *dev, unsigned char RxCnt)
         skb_reserve(skb, 2);
         insw(ioaddr + AM2150_RCV, skb_put(skb, pkt_len), pkt_len>>1);
         if (pkt_len & 1)
-            *(skb->tail-1) = inb(ioaddr + AM2150_RCV);
+            *(skb_tail_pointer(skb) - 1) = inb(ioaddr + AM2150_RCV);
         skb->protocol = eth_type_trans(skb, dev);
         
         netif_rx(skb); /* Send the packet to the upper (protocol) layers. */