diff --git a/Documentation/networking/mptcp-sysctl.rst b/Documentation/networking/mptcp-sysctl.rst index 1683c139821e..1eb6af26b4a7 100644 --- a/Documentation/networking/mptcp-sysctl.rst +++ b/Documentation/networking/mptcp-sysctl.rst @@ -8,9 +8,11 @@ MPTCP Sysfs variables =============================== add_addr_timeout - INTEGER (seconds) - Set the timeout after which an ADD_ADDR control message will be - resent to an MPTCP peer that has not acknowledged a previous - ADD_ADDR message. + Set the maximum value of timeout after which an ADD_ADDR control message + will be resent to an MPTCP peer that has not acknowledged a previous + ADD_ADDR message. A dynamically estimated retransmission timeout based + on the estimated connection round-trip-time is used if this value is + lower than the maximum one. Do not retransmit if set to 0. diff --git a/net/mptcp/pm.c b/net/mptcp/pm.c index 136a380602ca..204e1f61212e 100644 --- a/net/mptcp/pm.c +++ b/net/mptcp/pm.c @@ -268,6 +268,27 @@ int mptcp_pm_mp_prio_send_ack(struct mptcp_sock *msk, return -EINVAL; } +static unsigned int mptcp_adjust_add_addr_timeout(struct mptcp_sock *msk) +{ + const struct net *net = sock_net((struct sock *)msk); + unsigned int rto = mptcp_get_add_addr_timeout(net); + struct mptcp_subflow_context *subflow; + unsigned int max = 0; + + mptcp_for_each_subflow(msk, subflow) { + struct sock *ssk = mptcp_subflow_tcp_sock(subflow); + struct inet_connection_sock *icsk = inet_csk(ssk); + + if (icsk->icsk_rto > max) + max = icsk->icsk_rto; + } + + if (max && max < rto) + rto = max; + + return rto; +} + static void mptcp_pm_add_timer(struct timer_list *timer) { struct mptcp_pm_add_entry *entry = timer_container_of(entry, timer, @@ -292,7 +313,7 @@ static void mptcp_pm_add_timer(struct timer_list *timer) goto out; } - timeout = mptcp_get_add_addr_timeout(sock_net(sk)); + timeout = mptcp_adjust_add_addr_timeout(msk); if (!timeout) goto out; @@ -307,7 +328,7 @@ static void mptcp_pm_add_timer(struct timer_list *timer) if (entry->retrans_times < ADD_ADDR_RETRANS_MAX) sk_reset_timer(sk, timer, - jiffies + timeout); + jiffies + (timeout << entry->retrans_times)); spin_unlock_bh(&msk->pm.lock); @@ -348,7 +369,6 @@ bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, { struct mptcp_pm_add_entry *add_entry = NULL; struct sock *sk = (struct sock *)msk; - struct net *net = sock_net(sk); unsigned int timeout; lockdep_assert_held(&msk->pm.lock); @@ -374,7 +394,7 @@ bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, timer_setup(&add_entry->add_timer, mptcp_pm_add_timer, 0); reset_timer: - timeout = mptcp_get_add_addr_timeout(net); + timeout = mptcp_adjust_add_addr_timeout(msk); if (timeout) sk_reset_timer(sk, &add_entry->add_timer, jiffies + timeout);