Upgrade to 4.4.50-rt62

[kvmfornfv.git] / kernel / net / ipv4 / tcp_dctcp.c

diff --git a/kernel/net/ipv4/tcp_dctcp.c b/kernel/net/ipv4/tcp_dctcp.c
index 7e538f7..55d7da1 100644 (file)
--- a/kernel/net/ipv4/tcp_dctcp.c
+++ b/kernel/net/ipv4/tcp_dctcp.c
@@ -56,6 +56,7 @@ struct dctcp {
        u32 next_seq;
        u32 ce_state;
        u32 delayed_ack_reserved;
+       u32 loss_cwnd;
 };
 
 static unsigned int dctcp_shift_g __read_mostly = 4; /* g = 1/2^4 */
@@ -96,6 +97,7 @@ 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;
 
                dctcp_reset(tp, ca);
@@ -111,9 +113,10 @@ static void dctcp_init(struct sock *sk)
 
 static u32 dctcp_ssthresh(struct sock *sk)
 {
-       const struct dctcp *ca = inet_csk_ca(sk);
+       struct dctcp *ca = inet_csk_ca(sk);
        struct tcp_sock *tp = tcp_sk(sk);
 
+       ca->loss_cwnd = tp->snd_cwnd;
        return max(tp->snd_cwnd - ((tp->snd_cwnd * ca->dctcp_alpha) >> 11U), 2U);
 }
 
@@ -308,12 +311,20 @@ static size_t dctcp_get_info(struct sock *sk, u32 ext, int *attr,
        return 0;
 }
 
+static u32 dctcp_cwnd_undo(struct sock *sk)
+{
+       const struct dctcp *ca = inet_csk_ca(sk);
+
+       return max(tcp_sk(sk)->snd_cwnd, ca->loss_cwnd);
+}
+
 static struct tcp_congestion_ops dctcp __read_mostly = {
        .init           = dctcp_init,
        .in_ack_event   = dctcp_update_alpha,
        .cwnd_event     = dctcp_cwnd_event,
        .ssthresh       = dctcp_ssthresh,
        .cong_avoid     = tcp_reno_cong_avoid,
+       .undo_cwnd      = dctcp_cwnd_undo,
        .set_state      = dctcp_state,
        .get_info       = dctcp_get_info,
        .flags          = TCP_CONG_NEEDS_ECN,