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/ip_output.c b/net/ipv4/ip_output.c
index 67404e1..50e2973 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -1596,7 +1596,6 @@
arg->csumoffset) = csum_fold(csum_add(nskb->csum,
arg->csum));
nskb->ip_summed = CHECKSUM_NONE;
- skb_set_queue_mapping(nskb, skb_get_queue_mapping(skb));
ip_push_pending_frames(sk, &fl4);
}
out:
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;
}
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 9c68cf3..30dd45c 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -821,7 +821,6 @@
static int tcp_v4_send_synack(const struct sock *sk, struct dst_entry *dst,
struct flowi *fl,
struct request_sock *req,
- u16 queue_mapping,
struct tcp_fastopen_cookie *foc,
bool attach_req)
{
@@ -839,7 +838,6 @@
if (skb) {
__tcp_v4_send_check(skb, ireq->ir_loc_addr, ireq->ir_rmt_addr);
- skb_set_queue_mapping(skb, queue_mapping);
err = ip_build_and_send_pkt(skb, sk, ireq->ir_loc_addr,
ireq->ir_rmt_addr,
ireq->opt);
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 6e79fcb..19adedb 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -3518,7 +3518,7 @@
int res;
tcp_rsk(req)->txhash = net_tx_rndhash();
- res = af_ops->send_synack(sk, NULL, &fl, req, 0, NULL, true);
+ res = af_ops->send_synack(sk, NULL, &fl, req, NULL, true);
if (!res) {
TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_RETRANSSEGS);
NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPSYNRETRANS);