When mirred is invoked from the ingress path, and it wants to redirect
the processed packet, it can now use the ACT_REDIRECT action,
filling the tcf_result accordingly.
This avoids a skb_clone() in the TC S/W data path giving a ~10%
improvement in forwarding performances. Overall TC S/W performances
are now comparable to the kernel openswitch datapath.
Signed-off-by: Paolo Abeni <pab...@redhat.com>
---
net/sched/act_mirred.c | 15 +++++++++++++--
1 file changed, 13 insertions(+), 2 deletions(-)
diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c
index eeb335f03102..b19317426117 100644
--- a/net/sched/act_mirred.c
+++ b/net/sched/act_mirred.c
@@ -175,6 +175,7 @@ static int tcf_mirred(struct sk_buff *skb, const struct
tc_action *a,
struct net_device *dev;
struct sk_buff *skb2;
int retval, err = 0;
+ bool want_ingress;
int m_eaction;
int mac_len;
@@ -185,6 +186,17 @@ static int tcf_mirred(struct sk_buff *skb, const struct
tc_action *a,
m_eaction = READ_ONCE(m->tcfm_eaction);
retval = READ_ONCE(m->tcf_action);
dev = rcu_dereference_bh(m->tcfm_dev);
+ want_ingress = tcf_mirred_act_wants_ingress(m_eaction);
+ if (skb_at_tc_ingress(skb) && tcf_mirred_is_act_redirect(m_eaction)) {
+ skb->tc_redirected = 1;
+ skb->tc_from_ingress = 1;
+
+ /* the core redirect code will check dev and its status */
+ TCF_RESULT_SET_REDIRECT(res, dev, want_ingress);
+ res->qstats = this_cpu_ptr(m->common.cpu_qstats);
+ return TC_ACT_REDIRECT;
+ }
+
if (unlikely(!dev)) {
pr_notice_once("tc mirred: target device is gone\n");
goto out;
@@ -204,8 +216,7 @@ static int tcf_mirred(struct sk_buff *skb, const struct
tc_action *a,
* and devices expect a mac header on xmit, then mac push/pull is
* needed.
*/
- if (skb_at_tc_ingress(skb) != tcf_mirred_act_wants_ingress(m_eaction) &&
- m_mac_header_xmit) {
+ if (skb_at_tc_ingress(skb) != want_ingress && m_mac_header_xmit) {
if (!skb_at_tc_ingress(skb)) {
/* caught at egress, act ingress: pull mac */
mac_len = skb_network_header(skb) - skb_mac_header(skb);
--
2.17.1
