sched: Call skb_get_hash_perturb in sch_fq_codel

Call skb_get_hash_perturb instead of doing skb_flow_dissect and then
jhash by hand.
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/sched/sch_fq_codel.c

@@ -23,7 +23,6 @@
 #include <linux/vmalloc.h>
 #include <net/netlink.h>
 #include <net/pkt_sched.h>
-#include <net/flow_keys.h>
 #include <net/codel.h>
 
 /*	Fair Queue CoDel.
@@ -68,15 +67,9 @@ struct fq_codel_sched_data {
 };
 
 static unsigned int fq_codel_hash(const struct fq_codel_sched_data *q,
-				  const struct sk_buff *skb)
+				  struct sk_buff *skb)
 {
-	struct flow_keys keys;
-	unsigned int hash;
-
-	skb_flow_dissect(skb, &keys);
-	hash = jhash_3words((__force u32)keys.dst,
-			    (__force u32)keys.src ^ keys.ip_proto,
-			    (__force u32)keys.ports, q->perturbation);
+	u32 hash = skb_get_hash_perturb(skb, q->perturbation);
 
 	return reciprocal_scale(hash, q->flows_cnt);
 }