From 05cbc0db03e82128f2e7e353d4194dd24a1627fe Mon Sep 17 00:00:00 2001 From: Fan Du Date: Fri, 6 Mar 2015 11:18:24 +0800 Subject: ipv4: Create probe timer for tcp PMTU as per RFC4821 As per RFC4821 7.3. Selecting Probe Size, a probe timer should be armed once probing has converged. Once this timer expired, probing again to take advantage of any path PMTU change. The recommended probing interval is 10 minutes per RFC1981. Probing interval could be sysctled by sysctl_tcp_probe_interval. Eric Dumazet suggested to implement pseudo timer based on 32bits jiffies tcp_time_stamp instead of using classic timer for such rare event. Signed-off-by: Fan Du Signed-off-by: David S. Miller --- net/ipv4/tcp_timer.c | 1 + 1 file changed, 1 insertion(+) (limited to 'net/ipv4/tcp_timer.c') diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c index 0732b787904e..15505936511d 100644 --- a/net/ipv4/tcp_timer.c +++ b/net/ipv4/tcp_timer.c @@ -107,6 +107,7 @@ static void tcp_mtu_probing(struct inet_connection_sock *icsk, struct sock *sk) if (net->ipv4.sysctl_tcp_mtu_probing) { if (!icsk->icsk_mtup.enabled) { icsk->icsk_mtup.enabled = 1; + icsk->icsk_mtup.probe_timestamp = tcp_time_stamp; tcp_sync_mss(sk, icsk->icsk_pmtu_cookie); } else { struct net *net = sock_net(sk); -- cgit v1.2.3-59-g8ed1b