tcp: remove DELAYED ACK events in DCTCP

After fixing the way DCTCP tracking delayed ACKs, the delayed-ACK
related callbacks are no longer needed

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Lawrence Brakmo <brakmo@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/tcp.h b/include/net/tcp.h
index af3ec72d5d4163b57142309bf8df72365cf7018d..3482d13d655b88910e3d41d30584d94bfea7a535 100644 (file)
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -912,8 +912,6 @@ enum tcp_ca_event {
        CA_EVENT_LOSS,          /* loss timeout */
        CA_EVENT_ECN_NO_CE,     /* ECT set, but not CE marked */
        CA_EVENT_ECN_IS_CE,     /* received CE marked IP packet */
-       CA_EVENT_DELAYED_ACK,   /* Delayed ack is sent */
-       CA_EVENT_NON_DELAYED_ACK,
 };
 
 /* Information about inbound ACK, passed to cong_ops->in_ack_event() */

diff --git a/net/ipv4/tcp_dctcp.c b/net/ipv4/tcp_dctcp.c
index 89f88b0d81672b2c2278d6b3ee965757499e7992..5869f89ca6564ec46a3c04a2b344a8630b0ba459 100644 (file)
--- a/net/ipv4/tcp_dctcp.c
+++ b/net/ipv4/tcp_dctcp.c
@@ -55,7 +55,6 @@ struct dctcp {
        u32 dctcp_alpha;
        u32 next_seq;
        u32 ce_state;
-       u32 delayed_ack_reserved;
        u32 loss_cwnd;
 };
 
@@ -96,7 +95,6 @@ static void dctcp_init(struct sock *sk)
 
                ca->dctcp_alpha = min(dctcp_alpha_on_init, DCTCP_MAX_ALPHA);
 
-               ca->delayed_ack_reserved = 0;
                ca->loss_cwnd = 0;
                ca->ce_state = 0;
 
@@ -250,25 +248,6 @@ static void dctcp_state(struct sock *sk, u8 new_state)
        }
 }
 
-static void dctcp_update_ack_reserved(struct sock *sk, enum tcp_ca_event ev)
-{
-       struct dctcp *ca = inet_csk_ca(sk);
-
-       switch (ev) {
-       case CA_EVENT_DELAYED_ACK:
-               if (!ca->delayed_ack_reserved)
-                       ca->delayed_ack_reserved = 1;
-               break;
-       case CA_EVENT_NON_DELAYED_ACK:
-               if (ca->delayed_ack_reserved)
-                       ca->delayed_ack_reserved = 0;
-               break;
-       default:
-               /* Don't care for the rest. */
-               break;
-       }
-}
-
 static void dctcp_cwnd_event(struct sock *sk, enum tcp_ca_event ev)
 {
        switch (ev) {
@@ -278,10 +257,6 @@ static void dctcp_cwnd_event(struct sock *sk, enum tcp_ca_event ev)
        case CA_EVENT_ECN_NO_CE:
                dctcp_ce_state_1_to_0(sk);
                break;
-       case CA_EVENT_DELAYED_ACK:
-       case CA_EVENT_NON_DELAYED_ACK:
-               dctcp_update_ack_reserved(sk, ev);
-               break;
        default:
                /* Don't care for the rest. */
                break;

diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 8e08b409c71e1f8e69422f1756d48b5bc55411c3..00e5a300ddb934957463c4abdfbccb50807256e1 100644 (file)
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -3523,8 +3523,6 @@ void tcp_send_delayed_ack(struct sock *sk)
        int ato = icsk->icsk_ack.ato;
        unsigned long timeout;
 
-       tcp_ca_event(sk, CA_EVENT_DELAYED_ACK);
-
        if (ato > TCP_DELACK_MIN) {
                const struct tcp_sock *tp = tcp_sk(sk);
                int max_ato = HZ / 2;
@@ -3581,8 +3579,6 @@ void tcp_send_ack(struct sock *sk)
        if (sk->sk_state == TCP_CLOSE)
                return;
 
-       tcp_ca_event(sk, CA_EVENT_NON_DELAYED_ACK);
-
        /* We are not putting this on the write queue, so
         * tcp_transmit_skb() will set the ownership to this
         * sock.