1 files changed, 61 insertions, 21 deletions

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 981d1203b152..0a461232329f 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -115,8 +115,8 @@ int sysctl_tcp_abc = 1;
 /* Adapt the MSS value used to make delayed ack decision to the 
  * real world.
  */ 
-static inline void tcp_measure_rcv_mss(struct sock *sk,
-                                       const struct sk_buff *skb)
+static void tcp_measure_rcv_mss(struct sock *sk,
+                                const struct sk_buff *skb)
 {
         struct inet_connection_sock *icsk = inet_csk(sk);
         const unsigned int lss = icsk->icsk_ack.last_seg_size; 
@@ -246,8 +246,8 @@ static int __tcp_grow_window(const struct sock *sk, struct tcp_sock *tp,
         return 0;
 }
 
-static inline void tcp_grow_window(struct sock *sk, struct tcp_sock *tp,
-                                   struct sk_buff *skb)
+static void tcp_grow_window(struct sock *sk, struct tcp_sock *tp,
+                            struct sk_buff *skb)
 {
         /* Check #1 */
         if (tp->rcv_ssthresh < tp->window_clamp &&
@@ -341,6 +341,26 @@ static void tcp_clamp_window(struct sock *sk, struct tcp_sock *tp)
                 tp->rcv_ssthresh = min(tp->window_clamp, 2U*tp->advmss);
 }
 
+
+/* Initialize RCV_MSS value.
+ * RCV_MSS is an our guess about MSS used by the peer.
+ * We haven't any direct information about the MSS.
+ * It's better to underestimate the RCV_MSS rather than overestimate.
+ * Overestimations make us ACKing less frequently than needed.
+ * Underestimations are more easy to detect and fix by tcp_measure_rcv_mss().
+ */
+void tcp_initialize_rcv_mss(struct sock *sk)
+{
+        struct tcp_sock *tp = tcp_sk(sk);
+        unsigned int hint = min_t(unsigned int, tp->advmss, tp->mss_cache);
+
+        hint = min(hint, tp->rcv_wnd/2);
+        hint = min(hint, TCP_MIN_RCVMSS);
+        hint = max(hint, TCP_MIN_MSS);
+
+        inet_csk(sk)->icsk_ack.rcv_mss = hint;
+}
+
 /* Receiver "autotuning" code.
  *
  * The algorithm for RTT estimation w/o timestamps is based on
@@ -735,6 +755,27 @@ __u32 tcp_init_cwnd(struct tcp_sock *tp, struct dst_entry *dst)
         return min_t(__u32, cwnd, tp->snd_cwnd_clamp);
 }
 
+/* Set slow start threshold and cwnd not falling to slow start */
+void tcp_enter_cwr(struct sock *sk)
+{
+        struct tcp_sock *tp = tcp_sk(sk);
+
+        tp->prior_ssthresh = 0;
+        tp->bytes_acked = 0;
+        if (inet_csk(sk)->icsk_ca_state < TCP_CA_CWR) {
+                tp->undo_marker = 0;
+                tp->snd_ssthresh = inet_csk(sk)->icsk_ca_ops->ssthresh(sk);
+                tp->snd_cwnd = min(tp->snd_cwnd,
+                                   tcp_packets_in_flight(tp) + 1U);
+                tp->snd_cwnd_cnt = 0;
+                tp->high_seq = tp->snd_nxt;
+                tp->snd_cwnd_stamp = tcp_time_stamp;
+                TCP_ECN_queue_cwr(tp);
+
+                tcp_set_ca_state(sk, TCP_CA_CWR);
+        }
+}
+
 /* Initialize metrics on socket. */
 
 static void tcp_init_metrics(struct sock *sk)
@@ -2070,8 +2111,8 @@ static inline void tcp_ack_update_rtt(struct sock *sk, const int flag,
                 tcp_ack_no_tstamp(sk, seq_rtt, flag);
 }
 
-static inline void tcp_cong_avoid(struct sock *sk, u32 ack, u32 rtt,
-                                  u32 in_flight, int good)
+static void tcp_cong_avoid(struct sock *sk, u32 ack, u32 rtt,
+                           u32 in_flight, int good)
 {
         const struct inet_connection_sock *icsk = inet_csk(sk);
         icsk->icsk_ca_ops->cong_avoid(sk, ack, rtt, in_flight, good);
@@ -2082,7 +2123,7 @@ static inline void tcp_cong_avoid(struct sock *sk, u32 ack, u32 rtt,
  * RFC2988 recommends to restart timer to now+rto.
  */
 
-static inline void tcp_ack_packets_out(struct sock *sk, struct tcp_sock *tp)
+static void tcp_ack_packets_out(struct sock *sk, struct tcp_sock *tp)
 {
         if (!tp->packets_out) {
                 inet_csk_clear_xmit_timer(sk, ICSK_TIME_RETRANS);
@@ -2147,7 +2188,7 @@ static int tcp_tso_acked(struct sock *sk, struct sk_buff *skb,
         return acked;
 }
 
-static inline u32 tcp_usrtt(const struct sk_buff *skb)
+static u32 tcp_usrtt(const struct sk_buff *skb)
 {
         struct timeval tv, now;
 
@@ -2583,8 +2624,8 @@ void tcp_parse_options(struct sk_buff *skb, struct tcp_options_received *opt_rx,
 /* Fast parse options. This hopes to only see timestamps.
  * If it is wrong it falls back on tcp_parse_options().
  */
-static inline int tcp_fast_parse_options(struct sk_buff *skb, struct tcphdr *th,
-                                         struct tcp_sock *tp)
+static int tcp_fast_parse_options(struct sk_buff *skb, struct tcphdr *th,
+                                  struct tcp_sock *tp)
 {
         if (th->doff == sizeof(struct tcphdr)>>2) {
                 tp->rx_opt.saw_tstamp = 0;
@@ -2804,8 +2845,7 @@ static void tcp_fin(struct sk_buff *skb, struct sock *sk, struct tcphdr *th)
         }
 }
 
-static __inline__ int
-tcp_sack_extend(struct tcp_sack_block *sp, u32 seq, u32 end_seq)
+static inline int tcp_sack_extend(struct tcp_sack_block *sp, u32 seq, u32 end_seq)
 {
         if (!after(seq, sp->end_seq) && !after(sp->start_seq, end_seq)) {
                 if (before(seq, sp->start_seq))
@@ -2817,7 +2857,7 @@ tcp_sack_extend(struct tcp_sack_block *sp, u32 seq, u32 end_seq)
         return 0;
 }
 
-static inline void tcp_dsack_set(struct tcp_sock *tp, u32 seq, u32 end_seq)
+static void tcp_dsack_set(struct tcp_sock *tp, u32 seq, u32 end_seq)
 {
         if (tp->rx_opt.sack_ok && sysctl_tcp_dsack) {
                 if (before(seq, tp->rcv_nxt))
@@ -2832,7 +2872,7 @@ static inline void tcp_dsack_set(struct tcp_sock *tp, u32 seq, u32 end_seq)
         }
 }
 
-static inline void tcp_dsack_extend(struct tcp_sock *tp, u32 seq, u32 end_seq)
+static void tcp_dsack_extend(struct tcp_sock *tp, u32 seq, u32 end_seq)
 {
         if (!tp->rx_opt.dsack)
                 tcp_dsack_set(tp, seq, end_seq);
@@ -2890,7 +2930,7 @@ static void tcp_sack_maybe_coalesce(struct tcp_sock *tp)
         }
 }
 
-static __inline__ void tcp_sack_swap(struct tcp_sack_block *sack1, struct tcp_sack_block *sack2)
+static inline void tcp_sack_swap(struct tcp_sack_block *sack1, struct tcp_sack_block *sack2)
 {
         __u32 tmp;
 
@@ -3455,7 +3495,7 @@ void tcp_cwnd_application_limited(struct sock *sk)
         tp->snd_cwnd_stamp = tcp_time_stamp;
 }
 
-static inline int tcp_should_expand_sndbuf(struct sock *sk, struct tcp_sock *tp)
+static int tcp_should_expand_sndbuf(struct sock *sk, struct tcp_sock *tp)
 {
         /* If the user specified a specific send buffer setting, do
          * not modify it.
@@ -3502,7 +3542,7 @@ static void tcp_new_space(struct sock *sk)
         sk->sk_write_space(sk);
 }
 
-static inline void tcp_check_space(struct sock *sk)
+static void tcp_check_space(struct sock *sk)
 {
         if (sock_flag(sk, SOCK_QUEUE_SHRUNK)) {
                 sock_reset_flag(sk, SOCK_QUEUE_SHRUNK);
@@ -3512,7 +3552,7 @@ static inline void tcp_check_space(struct sock *sk)
         }
 }
 
-static __inline__ void tcp_data_snd_check(struct sock *sk, struct tcp_sock *tp)
+static inline void tcp_data_snd_check(struct sock *sk, struct tcp_sock *tp)
 {
         tcp_push_pending_frames(sk, tp);
         tcp_check_space(sk);
@@ -3544,7 +3584,7 @@ static void __tcp_ack_snd_check(struct sock *sk, int ofo_possible)
         }
 }
 
-static __inline__ void tcp_ack_snd_check(struct sock *sk)
+static inline void tcp_ack_snd_check(struct sock *sk)
 {
         if (!inet_csk_ack_scheduled(sk)) {
                 /* We sent a data segment already. */
@@ -3692,8 +3732,7 @@ static int __tcp_checksum_complete_user(struct sock *sk, struct sk_buff *skb)
         return result;
 }
 
-static __inline__ int
-tcp_checksum_complete_user(struct sock *sk, struct sk_buff *skb)
+static inline int tcp_checksum_complete_user(struct sock *sk, struct sk_buff *skb)
 {
         return skb->ip_summed != CHECKSUM_UNNECESSARY &&
                 __tcp_checksum_complete_user(sk, skb);
@@ -4474,3 +4513,4 @@ EXPORT_SYMBOL(sysctl_tcp_abc);
 EXPORT_SYMBOL(tcp_parse_options);
 EXPORT_SYMBOL(tcp_rcv_established);
 EXPORT_SYMBOL(tcp_rcv_state_process);
+EXPORT_SYMBOL(tcp_initialize_rcv_mss);