[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/net/sched/act_simple.c b/net/sched/act_simple.c
index c797118..ecbcfa5 100644
--- a/net/sched/act_simple.c
+++ b/net/sched/act_simple.c
@@ -155,7 +155,7 @@
static inline int tcf_simp_dump(struct sk_buff *skb, struct tc_action *a,
int bind, int ref)
{
- unsigned char *b = skb->tail;
+ unsigned char *b = skb_tail_pointer(skb);
struct tcf_defact *d = a->priv;
struct tc_defact opt;
struct tcf_t t;