[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/sch_cbq.c b/net/sched/sch_cbq.c
index d83414d..be98a01 100644
--- a/net/sched/sch_cbq.c
+++ b/net/sched/sch_cbq.c
@@ -1465,7 +1465,7 @@
static __inline__ int cbq_dump_rate(struct sk_buff *skb, struct cbq_class *cl)
{
- unsigned char *b = skb->tail;
+ unsigned char *b = skb_tail_pointer(skb);
RTA_PUT(skb, TCA_CBQ_RATE, sizeof(cl->R_tab->rate), &cl->R_tab->rate);
return skb->len;
@@ -1477,7 +1477,7 @@
static __inline__ int cbq_dump_lss(struct sk_buff *skb, struct cbq_class *cl)
{
- unsigned char *b = skb->tail;
+ unsigned char *b = skb_tail_pointer(skb);
struct tc_cbq_lssopt opt;
opt.flags = 0;
@@ -1502,7 +1502,7 @@
static __inline__ int cbq_dump_wrr(struct sk_buff *skb, struct cbq_class *cl)
{
- unsigned char *b = skb->tail;
+ unsigned char *b = skb_tail_pointer(skb);
struct tc_cbq_wrropt opt;
opt.flags = 0;
@@ -1520,7 +1520,7 @@
static __inline__ int cbq_dump_ovl(struct sk_buff *skb, struct cbq_class *cl)
{
- unsigned char *b = skb->tail;
+ unsigned char *b = skb_tail_pointer(skb);
struct tc_cbq_ovl opt;
opt.strategy = cl->ovl_strategy;
@@ -1537,7 +1537,7 @@
static __inline__ int cbq_dump_fopt(struct sk_buff *skb, struct cbq_class *cl)
{
- unsigned char *b = skb->tail;
+ unsigned char *b = skb_tail_pointer(skb);
struct tc_cbq_fopt opt;
if (cl->split || cl->defmap) {
@@ -1556,7 +1556,7 @@
#ifdef CONFIG_NET_CLS_POLICE
static __inline__ int cbq_dump_police(struct sk_buff *skb, struct cbq_class *cl)
{
- unsigned char *b = skb->tail;
+ unsigned char *b = skb_tail_pointer(skb);
struct tc_cbq_police opt;
if (cl->police) {
@@ -1590,14 +1590,14 @@
static int cbq_dump(struct Qdisc *sch, struct sk_buff *skb)
{
struct cbq_sched_data *q = qdisc_priv(sch);
- unsigned char *b = skb->tail;
+ unsigned char *b = skb_tail_pointer(skb);
struct rtattr *rta;
rta = (struct rtattr*)b;
RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
if (cbq_dump_attr(skb, &q->link) < 0)
goto rtattr_failure;
- rta->rta_len = skb->tail - b;
+ rta->rta_len = skb_tail_pointer(skb) - b;
return skb->len;
rtattr_failure:
@@ -1619,7 +1619,7 @@
struct sk_buff *skb, struct tcmsg *tcm)
{
struct cbq_class *cl = (struct cbq_class*)arg;
- unsigned char *b = skb->tail;
+ unsigned char *b = skb_tail_pointer(skb);
struct rtattr *rta;
if (cl->tparent)
@@ -1633,7 +1633,7 @@
RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
if (cbq_dump_attr(skb, cl) < 0)
goto rtattr_failure;
- rta->rta_len = skb->tail - b;
+ rta->rta_len = skb_tail_pointer(skb) - b;
return skb->len;
rtattr_failure: