tcp: do not set queue_mapping on SYNACK

At the time of commit fff3269907 ("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>
This commit is contained in:
Eric Dumazet
2015-10-16 13:00:01 -07:00
committed by David S. Miller
parent 951b5d959f
commit dc6ef6be52
6 changed files with 4 additions and 9 deletions

View File

@@ -3518,7 +3518,7 @@ int tcp_rtx_synack(const struct sock *sk, struct request_sock *req)
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);