[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/net/ieee80211/ieee80211_rx.c b/net/ieee80211/ieee80211_rx.c
index 59a765c49cf9..2b854941e06c 100644
--- a/net/ieee80211/ieee80211_rx.c
+++ b/net/ieee80211/ieee80211_rx.c
@@ -595,7 +595,7 @@ int ieee80211_rx(struct ieee80211_device *ieee, struct sk_buff *skb,
                 if (frag != 0)
                         flen -= hdrlen;
 
-                if (frag_skb->tail + flen > frag_skb->end) {
+                if (skb_tail_pointer(frag_skb) + flen > frag_skb->end) {
                         printk(KERN_WARNING "%s: host decrypted and "
                                "reassembled frame did not fit skb\n",
                                dev->name);