Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

[linux-2.6-microblaze.git] / net / ipv4 / tcp_dctcp.c

diff --git a/net/ipv4/tcp_dctcp.c b/net/ipv4/tcp_dctcp.c
index 5869f89..8b637f9 100644 (file)
--- a/net/ipv4/tcp_dctcp.c
+++ b/net/ipv4/tcp_dctcp.c
@@ -129,24 +129,14 @@ static void dctcp_ce_state_0_to_1(struct sock *sk)
        struct dctcp *ca = inet_csk_ca(sk);
        struct tcp_sock *tp = tcp_sk(sk);
 
-       /* State has changed from CE=0 to CE=1 and delayed
-        * ACK has not sent yet.
-        */
-       if (!ca->ce_state &&
-           inet_csk(sk)->icsk_ack.pending & ICSK_ACK_TIMER) {
-               u32 tmp_rcv_nxt;
-
-               /* Save current rcv_nxt. */
-               tmp_rcv_nxt = tp->rcv_nxt;
-
-               /* Generate previous ack with CE=0. */
-               tp->ecn_flags &= ~TCP_ECN_DEMAND_CWR;
-               tp->rcv_nxt = ca->prior_rcv_nxt;
-
-               tcp_send_ack(sk);
-
-               /* Recover current rcv_nxt. */
-               tp->rcv_nxt = tmp_rcv_nxt;
+       if (!ca->ce_state) {
+               /* State has changed from CE=0 to CE=1, force an immediate
+                * ACK to reflect the new CE state. If an ACK was delayed,
+                * send that first to reflect the prior CE state.
+                */
+               if (inet_csk(sk)->icsk_ack.pending & ICSK_ACK_TIMER)
+                       __tcp_send_ack(sk, ca->prior_rcv_nxt);
+               tcp_enter_quickack_mode(sk, 1);
        }
 
        ca->prior_rcv_nxt = tp->rcv_nxt;
@@ -160,24 +150,14 @@ static void dctcp_ce_state_1_to_0(struct sock *sk)
        struct dctcp *ca = inet_csk_ca(sk);
        struct tcp_sock *tp = tcp_sk(sk);
 
-       /* State has changed from CE=1 to CE=0 and delayed
-        * ACK has not sent yet.
-        */
-       if (ca->ce_state &&
-           inet_csk(sk)->icsk_ack.pending & ICSK_ACK_TIMER) {
-               u32 tmp_rcv_nxt;
-
-               /* Save current rcv_nxt. */
-               tmp_rcv_nxt = tp->rcv_nxt;
-
-               /* Generate previous ack with CE=1. */
-               tp->ecn_flags |= TCP_ECN_DEMAND_CWR;
-               tp->rcv_nxt = ca->prior_rcv_nxt;
-
-               tcp_send_ack(sk);
-
-               /* Recover current rcv_nxt. */
-               tp->rcv_nxt = tmp_rcv_nxt;
+       if (ca->ce_state) {
+               /* State has changed from CE=1 to CE=0, force an immediate
+                * ACK to reflect the new CE state. If an ACK was delayed,
+                * send that first to reflect the prior CE state.
+                */
+               if (inet_csk(sk)->icsk_ack.pending & ICSK_ACK_TIMER)
+                       __tcp_send_ack(sk, ca->prior_rcv_nxt);
+               tcp_enter_quickack_mode(sk, 1);
        }
 
        ca->prior_rcv_nxt = tp->rcv_nxt;