aboutsummaryrefslogtreecommitdiffstats
path: root/net/ipv4/tcp_input.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--net/ipv4/tcp_input.c35
1 files changed, 29 insertions, 6 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index f5622b250665..cc2ac5346b92 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -4249,6 +4249,8 @@ static void tcp_sack_new_ofo_skb(struct sock *sk, u32 seq, u32 end_seq)
* If the sack array is full, forget about the last one.
*/
if (this_sack >= TCP_NUM_SACKS) {
+ if (tp->compressed_ack)
+ tcp_send_ack(sk);
this_sack--;
tp->rx_opt.num_sacks--;
sp--;
@@ -5081,6 +5083,7 @@ static inline void tcp_data_snd_check(struct sock *sk)
static void __tcp_ack_snd_check(struct sock *sk, int ofo_possible)
{
struct tcp_sock *tp = tcp_sk(sk);
+ unsigned long rtt, delay;
/* More than one full frame received... */
if (((tp->rcv_nxt - tp->rcv_wup) > inet_csk(sk)->icsk_ack.rcv_mss &&
@@ -5092,15 +5095,35 @@ static void __tcp_ack_snd_check(struct sock *sk, int ofo_possible)
(tp->rcv_nxt - tp->copied_seq < sk->sk_rcvlowat ||
__tcp_select_window(sk) >= tp->rcv_wnd)) ||
/* We ACK each frame or... */
- tcp_in_quickack_mode(sk) ||
- /* We have out of order data. */
- (ofo_possible && !RB_EMPTY_ROOT(&tp->out_of_order_queue))) {
- /* Then ack it now */
+ tcp_in_quickack_mode(sk)) {
+send_now:
tcp_send_ack(sk);
- } else {
- /* Else, send delayed ack. */
+ return;
+ }
+
+ if (!ofo_possible || RB_EMPTY_ROOT(&tp->out_of_order_queue)) {
tcp_send_delayed_ack(sk);
+ return;
}
+
+ if (!tcp_is_sack(tp) || tp->compressed_ack >= 44)
+ goto send_now;
+ tp->compressed_ack++;
+
+ if (hrtimer_is_queued(&tp->compressed_ack_timer))
+ return;
+
+ /* compress ack timer : 5 % of rtt, but no more than 1 ms */
+
+ rtt = tp->rcv_rtt_est.rtt_us;
+ if (tp->srtt_us && tp->srtt_us < rtt)
+ rtt = tp->srtt_us;
+
+ delay = min_t(unsigned long, NSEC_PER_MSEC,
+ rtt * (NSEC_PER_USEC >> 3)/20);
+ sock_hold(sk);
+ hrtimer_start(&tp->compressed_ack_timer, ns_to_ktime(delay),
+ HRTIMER_MODE_REL_PINNED_SOFT);
}
static inline void tcp_ack_snd_check(struct sock *sk)