diff options
| author | Eric Dumazet <edumazet@google.com> | 2018-04-24 00:46:25 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2018-04-24 20:20:03 +0300 |
| commit | 8c2320e84c193d4d42b8446986afa2797fb411e1 (patch) | |
| tree | a48a7aee60f3098f9a0f50296500556f1dec8b91 | |
| parent | a06ac0d67d9fda7c255476c6391032319030045d (diff) | |
| download | linux-8c2320e84c193d4d42b8446986afa2797fb411e1.tar.xz | |
tcp: md5: only call tp->af_specific->md5_lookup() for md5 sockets
RETPOLINE made calls to tp->af_specific->md5_lookup() quite expensive,
given they have no result.
We can omit the calls for sockets that have no md5 keys.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/ipv4/tcp_output.c | 26 |
1 files changed, 14 insertions, 12 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 383cac0ff0ec..95feffb6d53f 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -585,14 +585,15 @@ static unsigned int tcp_syn_options(struct sock *sk, struct sk_buff *skb, unsigned int remaining = MAX_TCP_OPTION_SPACE; struct tcp_fastopen_request *fastopen = tp->fastopen_req; + *md5 = NULL; #ifdef CONFIG_TCP_MD5SIG - *md5 = tp->af_specific->md5_lookup(sk, sk); - if (*md5) { - opts->options |= OPTION_MD5; - remaining -= TCPOLEN_MD5SIG_ALIGNED; + if (unlikely(rcu_access_pointer(tp->md5sig_info))) { + *md5 = tp->af_specific->md5_lookup(sk, sk); + if (*md5) { + opts->options |= OPTION_MD5; + remaining -= TCPOLEN_MD5SIG_ALIGNED; + } } -#else - *md5 = NULL; #endif /* We always get an MSS option. The option bytes which will be seen in @@ -720,14 +721,15 @@ static unsigned int tcp_established_options(struct sock *sk, struct sk_buff *skb opts->options = 0; + *md5 = NULL; #ifdef CONFIG_TCP_MD5SIG - *md5 = tp->af_specific->md5_lookup(sk, sk); - if (unlikely(*md5)) { - opts->options |= OPTION_MD5; - size += TCPOLEN_MD5SIG_ALIGNED; + if (unlikely(rcu_access_pointer(tp->md5sig_info))) { + *md5 = tp->af_specific->md5_lookup(sk, sk); + if (*md5) { + opts->options |= OPTION_MD5; + size += TCPOLEN_MD5SIG_ALIGNED; + } } -#else - *md5 = NULL; #endif if (likely(tp->rx_opt.tstamp_ok)) { |