diff options
| author | Arnaldo Carvalho de Melo <acme@redhat.com> | 2007-04-19 20:29:13 -0700 |
|---|---|---|
| committer | David S. Miller <davem@sunset.davemloft.net> | 2007-04-25 22:26:28 -0700 |
| commit | 27a884dc3cb63b93c2b3b643f5b31eed5f8a4d26 (patch) | |
| tree | 5a267e40f9b94014be38dad5de0a52b6628834e0 /net/sched/ematch.c | |
| parent | be8bd86321fa7f06359d866ef61fb4d2f3e9dce9 (diff) | |
| download | lwn-27a884dc3cb63b93c2b3b643f5b31eed5f8a4d26.tar.gz lwn-27a884dc3cb63b93c2b3b643f5b31eed5f8a4d26.zip | |
[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>
Diffstat (limited to 'net/sched/ematch.c')
| -rw-r--r-- | net/sched/ematch.c | 17 |
1 files changed, 10 insertions, 7 deletions
diff --git a/net/sched/ematch.c b/net/sched/ematch.c index 959c306c5714..63146d339d81 100644 --- a/net/sched/ematch.c +++ b/net/sched/ematch.c @@ -418,17 +418,19 @@ void tcf_em_tree_destroy(struct tcf_proto *tp, struct tcf_ematch_tree *tree) int tcf_em_tree_dump(struct sk_buff *skb, struct tcf_ematch_tree *tree, int tlv) { int i; - struct rtattr * top_start = (struct rtattr*) skb->tail; - struct rtattr * list_start; + u8 *tail; + struct rtattr *top_start = (struct rtattr *)skb_tail_pointer(skb); + struct rtattr *list_start; RTA_PUT(skb, tlv, 0, NULL); RTA_PUT(skb, TCA_EMATCH_TREE_HDR, sizeof(tree->hdr), &tree->hdr); - list_start = (struct rtattr *) skb->tail; + list_start = (struct rtattr *)skb_tail_pointer(skb); RTA_PUT(skb, TCA_EMATCH_TREE_LIST, 0, NULL); + tail = skb_tail_pointer(skb); for (i = 0; i < tree->hdr.nmatches; i++) { - struct rtattr *match_start = (struct rtattr*) skb->tail; + struct rtattr *match_start = (struct rtattr *)tail; struct tcf_ematch *em = tcf_em_get_match(tree, i); struct tcf_ematch_hdr em_hdr = { .kind = em->ops ? em->ops->kind : TCF_EM_CONTAINER, @@ -447,11 +449,12 @@ int tcf_em_tree_dump(struct sk_buff *skb, struct tcf_ematch_tree *tree, int tlv) } else if (em->datalen > 0) RTA_PUT_NOHDR(skb, em->datalen, (void *) em->data); - match_start->rta_len = skb->tail - (u8*) match_start; + tail = skb_tail_pointer(skb); + match_start->rta_len = tail - (u8 *)match_start; } - list_start->rta_len = skb->tail - (u8 *) list_start; - top_start->rta_len = skb->tail - (u8 *) top_start; + list_start->rta_len = tail - (u8 *)list_start; + top_start->rta_len = tail - (u8 *)top_start; return 0; |