diff options
| author |   Eric Dumazet <edumazet@google.com> | 2018-11-27 15:03:21 -0800 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2018-11-30 13:28:03 -0800 |
| commit | 6015c71e656bb6895b416c31a8b7db457e45cecf (patch) | |
| tree | ba31e8ae21f52048e475daa33f6bb86df5bfc3b5 /net/ipv4/tcp_output.c | |
| parent | Merge branch 'tcp-take-a-bit-more-care-of-backlog-stress' (diff) | |
| download | linux-dev-6015c71e656bb6895b416c31a8b7db457e45cecf.tar.xz linux-dev-6015c71e656bb6895b416c31a8b7db457e45cecf.zip | |
tcp: md5: add tcp_md5_needed jump label
Most linux hosts never setup TCP MD5 keys. We can avoid a
cache line miss (accessing tp->md5ig_info) on RX and TX
using a jump label.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/tcp_output.c')
| -rw-r--r-- | net/ipv4/tcp_output.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index e4c1e51b18c1..d3b691f3a9e8 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -594,7 +594,8 @@ static unsigned int tcp_syn_options(struct sock *sk, struct sk_buff *skb, *md5 = NULL; #ifdef CONFIG_TCP_MD5SIG - if (unlikely(rcu_access_pointer(tp->md5sig_info))) { + if (static_key_false(&tcp_md5_needed) && + rcu_access_pointer(tp->md5sig_info)) { *md5 = tp->af_specific->md5_lookup(sk, sk); if (*md5) { opts->options |= OPTION_MD5; @@ -730,7 +731,8 @@ static unsigned int tcp_established_options(struct sock *sk, struct sk_buff *skb *md5 = NULL; #ifdef CONFIG_TCP_MD5SIG - if (unlikely(rcu_access_pointer(tp->md5sig_info))) { + if (static_key_false(&tcp_md5_needed) && + rcu_access_pointer(tp->md5sig_info)) { *md5 = tp->af_specific->md5_lookup(sk, sk); if (*md5) { opts->options |= OPTION_MD5; |