summaryrefslogtreecommitdiffstats
path: root/net/ipv4
diff options
context:
space:
mode:
authorEric Dumazet <edumazet@google.com>2016-12-03 11:14:55 -0800
committerDavid S. Miller <davem@davemloft.net>2016-12-05 13:32:23 -0500
commit12a59abc22d6664f7d3944f625ceefee92de8820 (patch)
tree1a440d08ebc7f478066b858f5b071beaebe16e0c /net/ipv4
parent75eefc6c59fd2c5f1ab95a3a113c217237d12a31 (diff)
downloadlinux-12a59abc22d6664f7d3944f625ceefee92de8820.tar.bz2
tcp: tcp_mtu_probe() is likely to exit early
Adding a likely() in tcp_mtu_probe() moves its code which used to be inlined in front of tcp_write_xmit() We still have a cache line miss to access icsk->icsk_mtup.enabled, we will probably have to reorganize fields to help data locality. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4')
-rw-r--r--net/ipv4/tcp_output.c18
1 files changed, 9 insertions, 9 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index d5c46749adab..5f04bee4c86a 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -1932,26 +1932,26 @@ static inline void tcp_mtu_check_reprobe(struct sock *sk)
*/
static int tcp_mtu_probe(struct sock *sk)
{
- struct tcp_sock *tp = tcp_sk(sk);
struct inet_connection_sock *icsk = inet_csk(sk);
+ struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *skb, *nskb, *next;
struct net *net = sock_net(sk);
- int len;
int probe_size;
int size_needed;
- int copy;
+ int copy, len;
int mss_now;
int interval;
/* Not currently probing/verifying,
* not in recovery,
* have enough cwnd, and
- * not SACKing (the variable headers throw things off) */
- if (!icsk->icsk_mtup.enabled ||
- icsk->icsk_mtup.probe_size ||
- inet_csk(sk)->icsk_ca_state != TCP_CA_Open ||
- tp->snd_cwnd < 11 ||
- tp->rx_opt.num_sacks || tp->rx_opt.dsack)
+ * not SACKing (the variable headers throw things off)
+ */
+ if (likely(!icsk->icsk_mtup.enabled ||
+ icsk->icsk_mtup.probe_size ||
+ inet_csk(sk)->icsk_ca_state != TCP_CA_Open ||
+ tp->snd_cwnd < 11 ||
+ tp->rx_opt.num_sacks || tp->rx_opt.dsack))
return -1;
/* Use binary search for probe_size between tcp_mss_base,