tcp: do not force quickack when receiving out-of-order packets

BugLink: http://bugs.launchpad.net/bugs/1815234
[ Upstream commit a3893637e1eb0ef5eb1bbc52b3a8d2dfa317a35d ]

As explained in commit 9f9843a751d0 ("tcp: properly handle stretch
acks in slow start"), TCP stacks have to consider how many packets
are acknowledged in one single ACK, because of GRO, but also
because of ACK compression or losses.

We plan to add SACK compression in the following patch, we
must therefore not call tcp_enter_quickack_mode()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 80038940598fb45249ac7de69f1541b27824c0c2..8e1006e262fd0c19953908a51e4978ae80de48a0 100644 (file)
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -4670,8 +4670,6 @@ drop:
        if (!before(TCP_SKB_CB(skb)->seq, tp->rcv_nxt + tcp_receive_window(tp)))
                goto out_of_window;
 
-       tcp_enter_quickack_mode(sk);
-
        if (before(TCP_SKB_CB(skb)->seq, tp->rcv_nxt)) {
                /* Partial packet, seq < rcv_next < end_seq */
                SOCK_DEBUG(sk, "partial packet: rcv_next %X seq %X - %X\n",