diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/net/sock.h | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/include/net/sock.h b/include/net/sock.h index 6dfe3aa22b97..1749e38d0301 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -913,7 +913,17 @@ static inline void sock_rps_record_flow_hash(__u32 hash) static inline void sock_rps_record_flow(const struct sock *sk) { #ifdef CONFIG_RPS - sock_rps_record_flow_hash(sk->sk_rxhash); + /* 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 } |