[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>
diff --git a/include/net/pkt_cls.h b/include/net/pkt_cls.h
index dcb3a91..4129df7 100644
--- a/include/net/pkt_cls.h
+++ b/include/net/pkt_cls.h
@@ -337,7 +337,7 @@
static inline int tcf_valid_offset(const struct sk_buff *skb,
const unsigned char *ptr, const int len)
{
- return unlikely((ptr + len) < skb->tail && ptr > skb->head);
+ return unlikely((ptr + len) < skb_tail_pointer(skb) && ptr > skb->head);
}
#ifdef CONFIG_NET_CLS_IND