[PATCH] net_sched: cls_flow: add key rxhash

[Changli Gao <xiaosuo@gmail.com>]

We can use rxhash to classify the traffic into flows. As rxhash maybe
supplied by NIC or RPS, it is cheaper.

Signed-off-by: Changli Gao <xiaosuo@gmail.com>
---
 include/linux/pkt_cls.h |    1 +
 net/sched/cls_flow.c    |    7 +++++++
 2 files changed, 8 insertions(+)
diff --git a/include/linux/pkt_cls.h b/include/linux/pkt_cls.h
index 7f6ba86..defbde2 100644
--- a/include/linux/pkt_cls.h
+++ b/include/linux/pkt_cls.h
@@ -332,6 +332,7 @@ enum {
 	FLOW_KEY_SKUID,
 	FLOW_KEY_SKGID,
 	FLOW_KEY_VLAN_TAG,
+	FLOW_KEY_RXHASH,
 	__FLOW_KEY_MAX,
 };
 
diff --git a/net/sched/cls_flow.c b/net/sched/cls_flow.c
index cd709f1..5b271a1 100644
--- a/net/sched/cls_flow.c
+++ b/net/sched/cls_flow.c
@@ -306,6 +306,11 @@ static u32 flow_get_vlan_tag(const struct sk_buff *skb)
 	return tag & VLAN_VID_MASK;
 }
 
+static u32 flow_get_rxhash(struct sk_buff *skb)
+{
+	return skb_get_rxhash(skb);
+}
+
 static u32 flow_key_get(struct sk_buff *skb, int key)
 {
 	switch (key) {
@@ -343,6 +348,8 @@ static u32 flow_key_get(struct sk_buff *skb, int key)
 		return flow_get_skgid(skb);
 	case FLOW_KEY_VLAN_TAG:
 		return flow_get_vlan_tag(skb);
+	case FLOW_KEY_RXHASH:
+		return flow_get_rxhash(skb);
 	default:
 		WARN_ON(1);
 		return 0;