tcp: remove DELAYED ACK events in DCTCP

[ Upstream commit a69258f7aa2623e0930212f09c586fd06674ad79 ]

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>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/include/net/tcp.h b/include/net/tcp.h
index 686e33ea76e7fe109c2e5b32ed9b3daea1252c67..eca8d65cad1e9ccd2ca7b28058e23b1d052750a9 100644 (file)
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -938,8 +938,6 @@ 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 1a9b88c8cf7263c016277163636eb361f57960d3..8b637f9f23a232a137f4a7f2d685a599cc063c1b 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;
 
@@ -230,25 +228,6 @@ 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) {
@@ -258,10 +237,6 @@ 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 3d8f6f342cb1965bdc7d690722545e4402404a5a..b2ead31afcbab34e7ff5a95a156b173e48b1bc73 100644 (file)
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -3513,8 +3513,6 @@ 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;
@@ -3571,8 +3569,6 @@ void __tcp_send_ack(struct sock *sk, u32 rcv_nxt)
        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.