netfilter: xt_CT: optimize XT_CT_NOTRACK

The percpu untracked ct are not currently used for XT_CT_NOTRACK.

xt_ct_tg_check()/xt_ct_target() provides a single ct.

Thats not optimal as the ct->ct_general.use cache line will bounce among
cpus.

Use the intended [1] thing : xt_ct_target() should select the percpu
object.

[1] Refs :
commit 5bfddbd46a ("netfilter: nf_conntrack: IPS_UNTRACKED bit")
commit b3c5163fe0 ("netfilter: nf_conntrack: per_cpu untracking")

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Eric Dumazet 2013-05-22 11:10:57 +00:00 committed by Pablo Neira Ayuso
parent 8892475386
commit 27e7190efd

View file

@ -26,6 +26,9 @@ static inline int xt_ct_target(struct sk_buff *skb, struct nf_conn *ct)
if (skb->nfct != NULL)
return XT_CONTINUE;
/* special case the untracked ct : we want the percpu object */
if (!ct)
ct = nf_ct_untracked_get();
atomic_inc(&ct->ct_general.use);
skb->nfct = &ct->ct_general;
skb->nfctinfo = IP_CT_NEW;
@ -186,8 +189,7 @@ static int xt_ct_tg_check(const struct xt_tgchk_param *par,
int ret = -EOPNOTSUPP;
if (info->flags & XT_CT_NOTRACK) {
ct = nf_ct_untracked_get();
atomic_inc(&ct->ct_general.use);
ct = NULL;
goto out;
}
@ -311,7 +313,7 @@ static void xt_ct_tg_destroy(const struct xt_tgdtor_param *par,
struct nf_conn *ct = info->ct;
struct nf_conn_help *help;
if (!nf_ct_is_untracked(ct)) {
if (ct && !nf_ct_is_untracked(ct)) {
help = nfct_help(ct);
if (help)
module_put(help->helper->me);
@ -319,8 +321,8 @@ static void xt_ct_tg_destroy(const struct xt_tgdtor_param *par,
nf_ct_l3proto_module_put(par->family);
xt_ct_destroy_timeout(ct);
nf_ct_put(info->ct);
}
nf_ct_put(info->ct);
}
static void xt_ct_tg_destroy_v0(const struct xt_tgdtor_param *par)