tcp: Remove TCPCT
TCPCT uses option-number 253, reserved for experimental use and should
not be used in production environments.
Further, TCPCT does not fully implement RFC 6013.
As a nice side-effect, removing TCPCT increases TCP's performance for
very short flows:
Doing an apache-benchmark with -c 100 -n 100000, sending HTTP-requests
for files of 1KB size.
before this patch:
average (among 7 runs) of 20845.5 Requests/Second
after:
average (among 7 runs) of 21403.6 Requests/Second
Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index b7ab868..b27c758 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -838,7 +838,6 @@
*/
static int tcp_v4_send_synack(struct sock *sk, struct dst_entry *dst,
struct request_sock *req,
- struct request_values *rvp,
u16 queue_mapping,
bool nocache)
{
@@ -851,7 +850,7 @@
if (!dst && (dst = inet_csk_route_req(sk, &fl4, req)) == NULL)
return -1;
- skb = tcp_make_synack(sk, dst, req, rvp, NULL);
+ skb = tcp_make_synack(sk, dst, req, NULL);
if (skb) {
__tcp_v4_send_check(skb, ireq->loc_addr, ireq->rmt_addr);
@@ -868,10 +867,9 @@
return err;
}
-static int tcp_v4_rtx_synack(struct sock *sk, struct request_sock *req,
- struct request_values *rvp)
+static int tcp_v4_rtx_synack(struct sock *sk, struct request_sock *req)
{
- int res = tcp_v4_send_synack(sk, NULL, req, rvp, 0, false);
+ int res = tcp_v4_send_synack(sk, NULL, req, 0, false);
if (!res)
TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_RETRANSSEGS);
@@ -1371,8 +1369,7 @@
static int tcp_v4_conn_req_fastopen(struct sock *sk,
struct sk_buff *skb,
struct sk_buff *skb_synack,
- struct request_sock *req,
- struct request_values *rvp)
+ struct request_sock *req)
{
struct tcp_sock *tp = tcp_sk(sk);
struct request_sock_queue *queue = &inet_csk(sk)->icsk_accept_queue;
@@ -1467,9 +1464,7 @@
int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
{
- struct tcp_extend_values tmp_ext;
struct tcp_options_received tmp_opt;
- const u8 *hash_location;
struct request_sock *req;
struct inet_request_sock *ireq;
struct tcp_sock *tp = tcp_sk(sk);
@@ -1519,42 +1514,7 @@
tcp_clear_options(&tmp_opt);
tmp_opt.mss_clamp = TCP_MSS_DEFAULT;
tmp_opt.user_mss = tp->rx_opt.user_mss;
- tcp_parse_options(skb, &tmp_opt, &hash_location, 0,
- want_cookie ? NULL : &foc);
-
- if (tmp_opt.cookie_plus > 0 &&
- tmp_opt.saw_tstamp &&
- !tp->rx_opt.cookie_out_never &&
- (sysctl_tcp_cookie_size > 0 ||
- (tp->cookie_values != NULL &&
- tp->cookie_values->cookie_desired > 0))) {
- u8 *c;
- u32 *mess = &tmp_ext.cookie_bakery[COOKIE_DIGEST_WORDS];
- int l = tmp_opt.cookie_plus - TCPOLEN_COOKIE_BASE;
-
- if (tcp_cookie_generator(&tmp_ext.cookie_bakery[0]) != 0)
- goto drop_and_release;
-
- /* Secret recipe starts with IP addresses */
- *mess++ ^= (__force u32)daddr;
- *mess++ ^= (__force u32)saddr;
-
- /* plus variable length Initiator Cookie */
- c = (u8 *)mess;
- while (l-- > 0)
- *c++ ^= *hash_location++;
-
- want_cookie = false; /* not our kind of cookie */
- tmp_ext.cookie_out_never = 0; /* false */
- tmp_ext.cookie_plus = tmp_opt.cookie_plus;
- } else if (!tp->rx_opt.cookie_in_always) {
- /* redundant indications, but ensure initialization. */
- tmp_ext.cookie_out_never = 1; /* true */
- tmp_ext.cookie_plus = 0;
- } else {
- goto drop_and_release;
- }
- tmp_ext.cookie_in_always = tp->rx_opt.cookie_in_always;
+ tcp_parse_options(skb, &tmp_opt, 0, want_cookie ? NULL : &foc);
if (want_cookie && !tmp_opt.saw_tstamp)
tcp_clear_options(&tmp_opt);
@@ -1636,7 +1596,6 @@
* of tcp_v4_send_synack()->tcp_select_initial_window().
*/
skb_synack = tcp_make_synack(sk, dst, req,
- (struct request_values *)&tmp_ext,
fastopen_cookie_present(&valid_foc) ? &valid_foc : NULL);
if (skb_synack) {
@@ -1660,8 +1619,7 @@
if (fastopen_cookie_present(&foc) && foc.len != 0)
NET_INC_STATS_BH(sock_net(sk),
LINUX_MIB_TCPFASTOPENPASSIVEFAIL);
- } else if (tcp_v4_conn_req_fastopen(sk, skb, skb_synack, req,
- (struct request_values *)&tmp_ext))
+ } else if (tcp_v4_conn_req_fastopen(sk, skb, skb_synack, req))
goto drop_and_free;
return 0;
@@ -2241,12 +2199,6 @@
if (inet_csk(sk)->icsk_bind_hash)
inet_put_port(sk);
- /* TCP Cookie Transactions */
- if (tp->cookie_values != NULL) {
- kref_put(&tp->cookie_values->kref,
- tcp_cookie_values_release);
- tp->cookie_values = NULL;
- }
BUG_ON(tp->fastopen_rsk != NULL);
/* If socket is aborted during connect operation */