[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>
This commit is contained in:
Arnaldo Carvalho de Melo
2007-04-19 20:29:13 -07:00
committed by David S. Miller
parent be8bd86321
commit 27a884dc3c
110 changed files with 396 additions and 329 deletions

View File

@@ -3115,7 +3115,7 @@ sctp_disposition_t sctp_sf_ootb(const struct sctp_endpoint *ep,
break;
ch_end = ((__u8 *)ch) + WORD_ROUND(ntohs(ch->length));
if (ch_end > skb->tail)
if (ch_end > skb_tail_pointer(skb))
break;
if (SCTP_CID_SHUTDOWN_ACK == ch->type)
@@ -3130,7 +3130,7 @@ sctp_disposition_t sctp_sf_ootb(const struct sctp_endpoint *ep,
return sctp_sf_pdiscard(ep, asoc, type, arg, commands);
ch = (sctp_chunkhdr_t *) ch_end;
} while (ch_end < skb->tail);
} while (ch_end < skb_tail_pointer(skb));
if (ootb_shut_ack)
sctp_sf_shut_8_4_5(ep, asoc, type, arg, commands);