tcp: do not set queue_mapping on SYNACK
At the time of commit fff326990789 ("tcp: reflect SYN queue_mapping into
SYNACK packets") we had little ways to cope with SYN floods.
We no longer need to reflect incoming skb queue mappings, and instead
can pick a TX queue based on cpu cooking the SYNACK, with normal XPS
affinities.
Note that all SYNACK retransmits were picking TX queue 0, this no longer
is a win given that SYNACK rtx are now distributed on all cpus.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 3b35c3f..944eaca 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -6236,7 +6236,7 @@
}
if (fastopen_sk) {
af_ops->send_synack(fastopen_sk, dst, &fl, req,
- skb_get_queue_mapping(skb), &foc, false);
+ &foc, false);
/* Add the child socket directly into the accept queue */
inet_csk_reqsk_queue_add(sk, req, fastopen_sk);
sk->sk_data_ready(sk);
@@ -6247,7 +6247,7 @@
if (!want_cookie)
inet_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT);
af_ops->send_synack(sk, dst, &fl, req,
- skb_get_queue_mapping(skb), &foc, !want_cookie);
+ &foc, !want_cookie);
if (want_cookie)
goto drop_and_free;
}