net: rfs: add a jump label
RFS is not commonly used, so add a jump label to avoid some conditionals
in fast path.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/sock.h b/include/net/sock.h
index 1749e38..2729e77 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -913,17 +913,20 @@ static inline void sock_rps_record_flow_hash(__u32 hash)
static inline void sock_rps_record_flow(const struct sock *sk)
{
#ifdef CONFIG_RPS
- /* Reading sk->sk_rxhash might incur an expensive cache line miss.
- *
- * TCP_ESTABLISHED does cover almost all states where RFS
- * might be useful, and is cheaper [1] than testing :
- * IPv4: inet_sk(sk)->inet_daddr
- * IPv6: ipv6_addr_any(&sk->sk_v6_daddr)
- * OR an additional socket flag
- * [1] : sk_state and sk_prot are in the same cache line.
- */
- if (sk->sk_state == TCP_ESTABLISHED)
- sock_rps_record_flow_hash(sk->sk_rxhash);
+ if (static_key_false(&rfs_needed)) {
+ /* Reading sk->sk_rxhash might incur an expensive cache line
+ * miss.
+ *
+ * TCP_ESTABLISHED does cover almost all states where RFS
+ * might be useful, and is cheaper [1] than testing :
+ * IPv4: inet_sk(sk)->inet_daddr
+ * IPv6: ipv6_addr_any(&sk->sk_v6_daddr)
+ * OR an additional socket flag
+ * [1] : sk_state and sk_prot are in the same cache line.
+ */
+ if (sk->sk_state == TCP_ESTABLISHED)
+ sock_rps_record_flow_hash(sk->sk_rxhash);
+ }
#endif
}