From 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 Mon Sep 17 00:00:00 2001 From: Yunhong Jiang Date: Tue, 4 Aug 2015 12:17:53 -0700 Subject: Add the rt linux 4.1.3-rt3 as base Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang --- kernel/net/ipv4/tcp_timer.c | 652 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 652 insertions(+) create mode 100644 kernel/net/ipv4/tcp_timer.c (limited to 'kernel/net/ipv4/tcp_timer.c') diff --git a/kernel/net/ipv4/tcp_timer.c b/kernel/net/ipv4/tcp_timer.c new file mode 100644 index 000000000..8c65dc147 --- /dev/null +++ b/kernel/net/ipv4/tcp_timer.c @@ -0,0 +1,652 @@ +/* + * INET An implementation of the TCP/IP protocol suite for the LINUX + * operating system. INET is implemented using the BSD Socket + * interface as the means of communication with the user level. + * + * Implementation of the Transmission Control Protocol(TCP). + * + * Authors: Ross Biro + * Fred N. van Kempen, + * Mark Evans, + * Corey Minyard + * Florian La Roche, + * Charles Hedrick, + * Linus Torvalds, + * Alan Cox, + * Matthew Dillon, + * Arnt Gulbrandsen, + * Jorge Cwik, + */ + +#include +#include +#include + +int sysctl_tcp_syn_retries __read_mostly = TCP_SYN_RETRIES; +int sysctl_tcp_synack_retries __read_mostly = TCP_SYNACK_RETRIES; +int sysctl_tcp_keepalive_time __read_mostly = TCP_KEEPALIVE_TIME; +int sysctl_tcp_keepalive_probes __read_mostly = TCP_KEEPALIVE_PROBES; +int sysctl_tcp_keepalive_intvl __read_mostly = TCP_KEEPALIVE_INTVL; +int sysctl_tcp_retries1 __read_mostly = TCP_RETR1; +int sysctl_tcp_retries2 __read_mostly = TCP_RETR2; +int sysctl_tcp_orphan_retries __read_mostly; +int sysctl_tcp_thin_linear_timeouts __read_mostly; + +static void tcp_write_err(struct sock *sk) +{ + sk->sk_err = sk->sk_err_soft ? : ETIMEDOUT; + sk->sk_error_report(sk); + + tcp_done(sk); + NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPABORTONTIMEOUT); +} + +/* Do not allow orphaned sockets to eat all our resources. + * This is direct violation of TCP specs, but it is required + * to prevent DoS attacks. It is called when a retransmission timeout + * or zero probe timeout occurs on orphaned socket. + * + * Criteria is still not confirmed experimentally and may change. + * We kill the socket, if: + * 1. If number of orphaned sockets exceeds an administratively configured + * limit. + * 2. If we have strong memory pressure. + */ +static int tcp_out_of_resources(struct sock *sk, bool do_reset) +{ + struct tcp_sock *tp = tcp_sk(sk); + int shift = 0; + + /* If peer does not open window for long time, or did not transmit + * anything for long time, penalize it. */ + if ((s32)(tcp_time_stamp - tp->lsndtime) > 2*TCP_RTO_MAX || !do_reset) + shift++; + + /* If some dubious ICMP arrived, penalize even more. */ + if (sk->sk_err_soft) + shift++; + + if (tcp_check_oom(sk, shift)) { + /* Catch exceptional cases, when connection requires reset. + * 1. Last segment was sent recently. */ + if ((s32)(tcp_time_stamp - tp->lsndtime) <= TCP_TIMEWAIT_LEN || + /* 2. Window is closed. */ + (!tp->snd_wnd && !tp->packets_out)) + do_reset = true; + if (do_reset) + tcp_send_active_reset(sk, GFP_ATOMIC); + tcp_done(sk); + NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPABORTONMEMORY); + return 1; + } + return 0; +} + +/* Calculate maximal number or retries on an orphaned socket. */ +static int tcp_orphan_retries(struct sock *sk, int alive) +{ + int retries = sysctl_tcp_orphan_retries; /* May be zero. */ + + /* We know from an ICMP that something is wrong. */ + if (sk->sk_err_soft && !alive) + retries = 0; + + /* However, if socket sent something recently, select some safe + * number of retries. 8 corresponds to >100 seconds with minimal + * RTO of 200msec. */ + if (retries == 0 && alive) + retries = 8; + return retries; +} + +static void tcp_mtu_probing(struct inet_connection_sock *icsk, struct sock *sk) +{ + struct net *net = sock_net(sk); + + /* Black hole detection */ + 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); + struct tcp_sock *tp = tcp_sk(sk); + int mss; + + mss = tcp_mtu_to_mss(sk, icsk->icsk_mtup.search_low) >> 1; + mss = min(net->ipv4.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); + } + } +} + +/* This function calculates a "timeout" which is equivalent to the timeout of a + * TCP connection after "boundary" unsuccessful, exponentially backed-off + * retransmissions with an initial RTO of TCP_RTO_MIN or TCP_TIMEOUT_INIT if + * syn_set flag is set. + */ +static bool retransmits_timed_out(struct sock *sk, + unsigned int boundary, + unsigned int timeout, + bool syn_set) +{ + unsigned int linear_backoff_thresh, start_ts; + unsigned int rto_base = syn_set ? TCP_TIMEOUT_INIT : TCP_RTO_MIN; + + if (!inet_csk(sk)->icsk_retransmits) + return false; + + start_ts = tcp_sk(sk)->retrans_stamp; + if (unlikely(!start_ts)) + start_ts = tcp_skb_timestamp(tcp_write_queue_head(sk)); + + if (likely(timeout == 0)) { + linear_backoff_thresh = ilog2(TCP_RTO_MAX/rto_base); + + if (boundary <= linear_backoff_thresh) + timeout = ((2 << boundary) - 1) * rto_base; + else + timeout = ((2 << linear_backoff_thresh) - 1) * rto_base + + (boundary - linear_backoff_thresh) * TCP_RTO_MAX; + } + return (tcp_time_stamp - start_ts) >= timeout; +} + +/* 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; + bool do_reset, syn_set = false; + + if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) { + if (icsk->icsk_retransmits) { + dst_negative_advice(sk); + if (tp->syn_fastopen || tp->syn_data) + tcp_fastopen_cache_set(sk, 0, NULL, true, 0); + if (tp->syn_data) + NET_INC_STATS_BH(sock_net(sk), + LINUX_MIB_TCPFASTOPENACTIVEFAIL); + } + retry_until = icsk->icsk_syn_retries ? : sysctl_tcp_syn_retries; + syn_set = true; + } else { + if (retransmits_timed_out(sk, sysctl_tcp_retries1, 0, 0)) { + /* Black hole detection */ + tcp_mtu_probing(icsk, sk); + + dst_negative_advice(sk); + } + + retry_until = sysctl_tcp_retries2; + if (sock_flag(sk, SOCK_DEAD)) { + const int alive = icsk->icsk_rto < TCP_RTO_MAX; + + retry_until = tcp_orphan_retries(sk, alive); + do_reset = alive || + !retransmits_timed_out(sk, retry_until, 0, 0); + + if (tcp_out_of_resources(sk, do_reset)) + return 1; + } + } + + if (retransmits_timed_out(sk, retry_until, + syn_set ? 0 : icsk->icsk_user_timeout, syn_set)) { + /* Has it gone just too far? */ + tcp_write_err(sk); + return 1; + } + return 0; +} + +void tcp_delack_timer_handler(struct sock *sk) +{ + struct tcp_sock *tp = tcp_sk(sk); + struct inet_connection_sock *icsk = inet_csk(sk); + + sk_mem_reclaim_partial(sk); + + if (sk->sk_state == TCP_CLOSE || !(icsk->icsk_ack.pending & ICSK_ACK_TIMER)) + goto out; + + if (time_after(icsk->icsk_ack.timeout, jiffies)) { + sk_reset_timer(sk, &icsk->icsk_delack_timer, icsk->icsk_ack.timeout); + goto out; + } + icsk->icsk_ack.pending &= ~ICSK_ACK_TIMER; + + if (!skb_queue_empty(&tp->ucopy.prequeue)) { + struct sk_buff *skb; + + NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPSCHEDULERFAILED); + + while ((skb = __skb_dequeue(&tp->ucopy.prequeue)) != NULL) + sk_backlog_rcv(sk, skb); + + tp->ucopy.memory = 0; + } + + if (inet_csk_ack_scheduled(sk)) { + if (!icsk->icsk_ack.pingpong) { + /* Delayed ACK missed: inflate ATO. */ + icsk->icsk_ack.ato = min(icsk->icsk_ack.ato << 1, icsk->icsk_rto); + } else { + /* Delayed ACK missed: leave pingpong mode and + * deflate ATO. + */ + icsk->icsk_ack.pingpong = 0; + icsk->icsk_ack.ato = TCP_ATO_MIN; + } + tcp_send_ack(sk); + NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_DELAYEDACKS); + } + +out: + if (sk_under_memory_pressure(sk)) + sk_mem_reclaim(sk); +} + +static void tcp_delack_timer(unsigned long data) +{ + struct sock *sk = (struct sock *)data; + + bh_lock_sock(sk); + if (!sock_owned_by_user(sk)) { + tcp_delack_timer_handler(sk); + } else { + inet_csk(sk)->icsk_ack.blocked = 1; + NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_DELAYEDACKLOCKED); + /* deleguate our work to tcp_release_cb() */ + if (!test_and_set_bit(TCP_DELACK_TIMER_DEFERRED, &tcp_sk(sk)->tsq_flags)) + sock_hold(sk); + } + bh_unlock_sock(sk); + sock_put(sk); +} + +static void tcp_probe_timer(struct sock *sk) +{ + struct inet_connection_sock *icsk = inet_csk(sk); + struct tcp_sock *tp = tcp_sk(sk); + int max_probes; + u32 start_ts; + + if (tp->packets_out || !tcp_send_head(sk)) { + icsk->icsk_probes_out = 0; + return; + } + + /* RFC 1122 4.2.2.17 requires the sender to stay open indefinitely as + * long as the receiver continues to respond probes. We support this by + * default and reset icsk_probes_out with incoming ACKs. But if the + * socket is orphaned or the user specifies TCP_USER_TIMEOUT, we + * kill the socket when the retry count and the time exceeds the + * corresponding system limit. We also implement similar policy when + * we use RTO to probe window in tcp_retransmit_timer(). + */ + start_ts = tcp_skb_timestamp(tcp_send_head(sk)); + if (!start_ts) + skb_mstamp_get(&tcp_send_head(sk)->skb_mstamp); + else if (icsk->icsk_user_timeout && + (s32)(tcp_time_stamp - start_ts) > icsk->icsk_user_timeout) + goto abort; + + max_probes = sysctl_tcp_retries2; + if (sock_flag(sk, SOCK_DEAD)) { + const int alive = inet_csk_rto_backoff(icsk, TCP_RTO_MAX) < TCP_RTO_MAX; + + max_probes = tcp_orphan_retries(sk, alive); + if (!alive && icsk->icsk_backoff >= max_probes) + goto abort; + if (tcp_out_of_resources(sk, true)) + return; + } + + if (icsk->icsk_probes_out > max_probes) { +abort: tcp_write_err(sk); + } else { + /* Only send another probe if we didn't close things up. */ + tcp_send_probe0(sk); + } +} + +/* + * Timer for Fast Open socket to retransmit SYNACK. Note that the + * sk here is the child socket, not the parent (listener) socket. + */ +static void tcp_fastopen_synack_timer(struct sock *sk) +{ + struct inet_connection_sock *icsk = inet_csk(sk); + int max_retries = icsk->icsk_syn_retries ? : + sysctl_tcp_synack_retries + 1; /* add one more retry for fastopen */ + struct request_sock *req; + + req = tcp_sk(sk)->fastopen_rsk; + req->rsk_ops->syn_ack_timeout(req); + + if (req->num_timeout >= max_retries) { + tcp_write_err(sk); + return; + } + /* XXX (TFO) - Unlike regular SYN-ACK retransmit, we ignore error + * returned from rtx_syn_ack() to make it more persistent like + * regular retransmit because if the child socket has been accepted + * it's not good to give up too easily. + */ + inet_rtx_syn_ack(sk, req); + req->num_timeout++; + inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, + TCP_TIMEOUT_INIT << req->num_timeout, TCP_RTO_MAX); +} + +/* + * The TCP retransmit timer. + */ + +void tcp_retransmit_timer(struct sock *sk) +{ + struct tcp_sock *tp = tcp_sk(sk); + struct inet_connection_sock *icsk = inet_csk(sk); + + if (tp->fastopen_rsk) { + WARN_ON_ONCE(sk->sk_state != TCP_SYN_RECV && + sk->sk_state != TCP_FIN_WAIT1); + tcp_fastopen_synack_timer(sk); + /* Before we receive ACK to our SYN-ACK don't retransmit + * anything else (e.g., data or FIN segments). + */ + return; + } + if (!tp->packets_out) + goto out; + + WARN_ON(tcp_write_queue_empty(sk)); + + tp->tlp_high_seq = 0; + + if (!tp->snd_wnd && !sock_flag(sk, SOCK_DEAD) && + !((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV))) { + /* Receiver dastardly shrinks window. Our retransmits + * become zero probes, but we should not timeout this + * connection. If the socket is an orphan, time it out, + * we cannot allow such beasts to hang infinitely. + */ + struct inet_sock *inet = inet_sk(sk); + if (sk->sk_family == AF_INET) { + net_dbg_ratelimited("Peer %pI4:%u/%u unexpectedly shrunk window %u:%u (repaired)\n", + &inet->inet_daddr, + ntohs(inet->inet_dport), + inet->inet_num, + tp->snd_una, tp->snd_nxt); + } +#if IS_ENABLED(CONFIG_IPV6) + else if (sk->sk_family == AF_INET6) { + net_dbg_ratelimited("Peer %pI6:%u/%u unexpectedly shrunk window %u:%u (repaired)\n", + &sk->sk_v6_daddr, + ntohs(inet->inet_dport), + inet->inet_num, + tp->snd_una, tp->snd_nxt); + } +#endif + if (tcp_time_stamp - tp->rcv_tstamp > TCP_RTO_MAX) { + tcp_write_err(sk); + goto out; + } + tcp_enter_loss(sk); + tcp_retransmit_skb(sk, tcp_write_queue_head(sk)); + __sk_dst_reset(sk); + goto out_reset_timer; + } + + if (tcp_write_timeout(sk)) + goto out; + + if (icsk->icsk_retransmits == 0) { + int mib_idx; + + if (icsk->icsk_ca_state == TCP_CA_Recovery) { + if (tcp_is_sack(tp)) + mib_idx = LINUX_MIB_TCPSACKRECOVERYFAIL; + else + mib_idx = LINUX_MIB_TCPRENORECOVERYFAIL; + } else if (icsk->icsk_ca_state == TCP_CA_Loss) { + mib_idx = LINUX_MIB_TCPLOSSFAILURES; + } else if ((icsk->icsk_ca_state == TCP_CA_Disorder) || + tp->sacked_out) { + if (tcp_is_sack(tp)) + mib_idx = LINUX_MIB_TCPSACKFAILURES; + else + mib_idx = LINUX_MIB_TCPRENOFAILURES; + } else { + mib_idx = LINUX_MIB_TCPTIMEOUTS; + } + NET_INC_STATS_BH(sock_net(sk), mib_idx); + } + + tcp_enter_loss(sk); + + if (tcp_retransmit_skb(sk, tcp_write_queue_head(sk)) > 0) { + /* Retransmission failed because of local congestion, + * do not backoff. + */ + if (!icsk->icsk_retransmits) + icsk->icsk_retransmits = 1; + inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, + min(icsk->icsk_rto, TCP_RESOURCE_PROBE_INTERVAL), + TCP_RTO_MAX); + goto out; + } + + /* Increase the timeout each time we retransmit. Note that + * we do not increase the rtt estimate. rto is initialized + * from rtt, but increases here. Jacobson (SIGCOMM 88) suggests + * that doubling rto each time is the least we can get away with. + * In KA9Q, Karn uses this for the first few times, and then + * goes to quadratic. netBSD doubles, but only goes up to *64, + * and clamps at 1 to 64 sec afterwards. Note that 120 sec is + * defined in the protocol as the maximum possible RTT. I guess + * we'll have to use something other than TCP to talk to the + * University of Mars. + * + * PAWS allows us longer timeouts and large windows, so once + * implemented ftp to mars will work nicely. We will have to fix + * the 120 second clamps though! + */ + icsk->icsk_backoff++; + icsk->icsk_retransmits++; + +out_reset_timer: + /* If stream is thin, use linear timeouts. Since 'icsk_backoff' is + * used to reset timer, set to 0. Recalculate 'icsk_rto' as this + * might be increased if the stream oscillates between thin and thick, + * thus the old value might already be too high compared to the value + * set by 'tcp_set_rto' in tcp_input.c which resets the rto without + * backoff. Limit to TCP_THIN_LINEAR_RETRIES before initiating + * exponential backoff behaviour to avoid continue hammering + * linear-timeout retransmissions into a black hole + */ + if (sk->sk_state == TCP_ESTABLISHED && + (tp->thin_lto || sysctl_tcp_thin_linear_timeouts) && + tcp_stream_is_thin(tp) && + icsk->icsk_retransmits <= TCP_THIN_LINEAR_RETRIES) { + icsk->icsk_backoff = 0; + icsk->icsk_rto = min(__tcp_set_rto(tp), TCP_RTO_MAX); + } else { + /* Use normal (exponential) backoff */ + icsk->icsk_rto = min(icsk->icsk_rto << 1, TCP_RTO_MAX); + } + inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, icsk->icsk_rto, TCP_RTO_MAX); + if (retransmits_timed_out(sk, sysctl_tcp_retries1 + 1, 0, 0)) + __sk_dst_reset(sk); + +out:; +} + +void tcp_write_timer_handler(struct sock *sk) +{ + struct inet_connection_sock *icsk = inet_csk(sk); + int event; + + if (sk->sk_state == TCP_CLOSE || !icsk->icsk_pending) + goto out; + + if (time_after(icsk->icsk_timeout, jiffies)) { + sk_reset_timer(sk, &icsk->icsk_retransmit_timer, icsk->icsk_timeout); + goto out; + } + + event = icsk->icsk_pending; + + switch (event) { + case ICSK_TIME_EARLY_RETRANS: + tcp_resume_early_retransmit(sk); + break; + case ICSK_TIME_LOSS_PROBE: + tcp_send_loss_probe(sk); + break; + case ICSK_TIME_RETRANS: + icsk->icsk_pending = 0; + tcp_retransmit_timer(sk); + break; + case ICSK_TIME_PROBE0: + icsk->icsk_pending = 0; + tcp_probe_timer(sk); + break; + } + +out: + sk_mem_reclaim(sk); +} + +static void tcp_write_timer(unsigned long data) +{ + struct sock *sk = (struct sock *)data; + + bh_lock_sock(sk); + if (!sock_owned_by_user(sk)) { + tcp_write_timer_handler(sk); + } else { + /* deleguate our work to tcp_release_cb() */ + if (!test_and_set_bit(TCP_WRITE_TIMER_DEFERRED, &tcp_sk(sk)->tsq_flags)) + sock_hold(sk); + } + bh_unlock_sock(sk); + sock_put(sk); +} + +void tcp_syn_ack_timeout(const struct request_sock *req) +{ + struct net *net = read_pnet(&inet_rsk(req)->ireq_net); + + NET_INC_STATS_BH(net, LINUX_MIB_TCPTIMEOUTS); +} +EXPORT_SYMBOL(tcp_syn_ack_timeout); + +void tcp_set_keepalive(struct sock *sk, int val) +{ + if ((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN)) + return; + + if (val && !sock_flag(sk, SOCK_KEEPOPEN)) + inet_csk_reset_keepalive_timer(sk, keepalive_time_when(tcp_sk(sk))); + else if (!val) + inet_csk_delete_keepalive_timer(sk); +} + + +static void tcp_keepalive_timer (unsigned long data) +{ + struct sock *sk = (struct sock *) data; + struct inet_connection_sock *icsk = inet_csk(sk); + struct tcp_sock *tp = tcp_sk(sk); + u32 elapsed; + + /* Only process if socket is not in use. */ + bh_lock_sock(sk); + if (sock_owned_by_user(sk)) { + /* Try again later. */ + inet_csk_reset_keepalive_timer (sk, HZ/20); + goto out; + } + + if (sk->sk_state == TCP_LISTEN) { + pr_err("Hmm... keepalive on a LISTEN ???\n"); + goto out; + } + + if (sk->sk_state == TCP_FIN_WAIT2 && sock_flag(sk, SOCK_DEAD)) { + if (tp->linger2 >= 0) { + const int tmo = tcp_fin_time(sk) - TCP_TIMEWAIT_LEN; + + if (tmo > 0) { + tcp_time_wait(sk, TCP_FIN_WAIT2, tmo); + goto out; + } + } + tcp_send_active_reset(sk, GFP_ATOMIC); + goto death; + } + + if (!sock_flag(sk, SOCK_KEEPOPEN) || sk->sk_state == TCP_CLOSE) + goto out; + + elapsed = keepalive_time_when(tp); + + /* It is alive without keepalive 8) */ + if (tp->packets_out || tcp_send_head(sk)) + goto resched; + + elapsed = keepalive_time_elapsed(tp); + + if (elapsed >= keepalive_time_when(tp)) { + /* If the TCP_USER_TIMEOUT option is enabled, use that + * to determine when to timeout instead. + */ + if ((icsk->icsk_user_timeout != 0 && + elapsed >= icsk->icsk_user_timeout && + icsk->icsk_probes_out > 0) || + (icsk->icsk_user_timeout == 0 && + icsk->icsk_probes_out >= keepalive_probes(tp))) { + tcp_send_active_reset(sk, GFP_ATOMIC); + tcp_write_err(sk); + goto out; + } + if (tcp_write_wakeup(sk) <= 0) { + icsk->icsk_probes_out++; + elapsed = keepalive_intvl_when(tp); + } else { + /* If keepalive was lost due to local congestion, + * try harder. + */ + elapsed = TCP_RESOURCE_PROBE_INTERVAL; + } + } else { + /* It is tp->rcv_tstamp + keepalive_time_when(tp) */ + elapsed = keepalive_time_when(tp) - elapsed; + } + + sk_mem_reclaim(sk); + +resched: + inet_csk_reset_keepalive_timer (sk, elapsed); + goto out; + +death: + tcp_done(sk); + +out: + bh_unlock_sock(sk); + sock_put(sk); +} + +void tcp_init_xmit_timers(struct sock *sk) +{ + inet_csk_init_xmit_timers(sk, &tcp_write_timer, &tcp_delack_timer, + &tcp_keepalive_timer); +} +EXPORT_SYMBOL(tcp_init_xmit_timers); -- cgit 1.2.3-korg