diff options
Diffstat (limited to 'net/ipv4/tcp_timer.c')
-rw-r--r-- | net/ipv4/tcp_timer.c | 35 |
1 files changed, 21 insertions, 14 deletions
diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c index d8970ec..8f14808 100644 --- a/net/ipv4/tcp_timer.c +++ b/net/ipv4/tcp_timer.c @@ -114,13 +114,31 @@ static int tcp_orphan_retries(struct sock *sk, int alive) return retries; } +static void tcp_mtu_probing(struct inet_connection_sock *icsk, struct sock *sk) +{ + int mss; + + /* Black hole detection */ + if (sysctl_tcp_mtu_probing) { + if (!icsk->icsk_mtup.enabled) { + icsk->icsk_mtup.enabled = 1; + tcp_sync_mss(sk, icsk->icsk_pmtu_cookie); + } else { + struct tcp_sock *tp = tcp_sk(sk); + mss = tcp_mtu_to_mss(sk, icsk->icsk_mtup.search_low)/2; + mss = min(sysctl_tcp_base_mss, mss); + mss = max(mss, 68 - tp->tcp_header_len); + icsk->icsk_mtup.search_low = tcp_mss_to_mtu(sk, mss); + tcp_sync_mss(sk, icsk->icsk_pmtu_cookie); + } + } +} + /* A write timeout has occurred. Process the after effects. */ static int tcp_write_timeout(struct sock *sk) { struct inet_connection_sock *icsk = inet_csk(sk); - struct tcp_sock *tp = tcp_sk(sk); int retry_until; - int mss; if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) { if (icsk->icsk_retransmits) @@ -129,18 +147,7 @@ static int tcp_write_timeout(struct sock *sk) } else { if (icsk->icsk_retransmits >= sysctl_tcp_retries1) { /* Black hole detection */ - if (sysctl_tcp_mtu_probing) { - if (!icsk->icsk_mtup.enabled) { - icsk->icsk_mtup.enabled = 1; - tcp_sync_mss(sk, icsk->icsk_pmtu_cookie); - } else { - mss = min(sysctl_tcp_base_mss, - tcp_mtu_to_mss(sk, icsk->icsk_mtup.search_low)/2); - mss = max(mss, 68 - tp->tcp_header_len); - icsk->icsk_mtup.search_low = tcp_mss_to_mtu(sk, mss); - tcp_sync_mss(sk, icsk->icsk_pmtu_cookie); - } - } + tcp_mtu_probing(icsk, sk); dst_negative_advice(&sk->sk_dst_cache); } |