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[SK_BUFF]: Convert skb->tail to sk_buff_data_t

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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
Download Patch File Download Diff File Expand all files Collapse all files

10
net/sched/sch_htb.c
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@@ -1110,7 +1110,7 @@ static int htb_init(struct Qdisc *sch, struct rtattr *opt)
static int htb_dump(struct Qdisc *sch, struct sk_buff *skb)
{
struct htb_sched *q = qdisc_priv(sch);
unsigned char *b = skb->tail;
unsigned char *b = skb_tail_pointer(skb);
struct rtattr *rta;
struct tc_htb_glob gopt;
spin_lock_bh(&sch->dev->queue_lock);
@@ -1123,12 +1123,12 @@ static int htb_dump(struct Qdisc *sch, struct sk_buff *skb)
rta = (struct rtattr *)b;
RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
RTA_PUT(skb, TCA_HTB_INIT, sizeof(gopt), &gopt);
rta->rta_len = skb->tail - b;
rta->rta_len = skb_tail_pointer(skb) - b;
spin_unlock_bh(&sch->dev->queue_lock);
return skb->len;
rtattr_failure:
spin_unlock_bh(&sch->dev->queue_lock);
skb_trim(skb, skb->tail - skb->data);
skb_trim(skb, skb_tail_pointer(skb) - skb->data);
return -1;
}
@@ -1136,7 +1136,7 @@ static int htb_dump_class(struct Qdisc *sch, unsigned long arg,
struct sk_buff *skb, struct tcmsg *tcm)
{
struct htb_class *cl = (struct htb_class *)arg;
unsigned char *b = skb->tail;
unsigned char *b = skb_tail_pointer(skb);
struct rtattr *rta;
struct tc_htb_opt opt;
@@ -1159,7 +1159,7 @@ static int htb_dump_class(struct Qdisc *sch, unsigned long arg,
opt.prio = cl->un.leaf.prio;
opt.level = cl->level;
RTA_PUT(skb, TCA_HTB_PARMS, sizeof(opt), &opt);
rta->rta_len = skb->tail - b;
rta->rta_len = skb_tail_pointer(skb) - b;
spin_unlock_bh(&sch->dev->queue_lock);
return skb->len;
rtattr_failure: