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_minisocks.c b/net/ipv4/tcp_minisocks.c
index 4bdb09f..8f0234f 100644
--- a/net/ipv4/tcp_minisocks.c
+++ b/net/ipv4/tcp_minisocks.c
@@ -93,13 +93,12 @@
const struct tcphdr *th)
{
struct tcp_options_received tmp_opt;
- const u8 *hash_location;
struct tcp_timewait_sock *tcptw = tcp_twsk((struct sock *)tw);
bool paws_reject = false;
tmp_opt.saw_tstamp = 0;
if (th->doff > (sizeof(*th) >> 2) && tcptw->tw_ts_recent_stamp) {
- tcp_parse_options(skb, &tmp_opt, &hash_location, 0, NULL);
+ tcp_parse_options(skb, &tmp_opt, 0, NULL);
if (tmp_opt.saw_tstamp) {
tmp_opt.rcv_tsecr -= tcptw->tw_ts_offset;
@@ -388,32 +387,6 @@
struct tcp_request_sock *treq = tcp_rsk(req);
struct inet_connection_sock *newicsk = inet_csk(newsk);
struct tcp_sock *newtp = tcp_sk(newsk);
- struct tcp_sock *oldtp = tcp_sk(sk);
- struct tcp_cookie_values *oldcvp = oldtp->cookie_values;
-
- /* TCP Cookie Transactions require space for the cookie pair,
- * as it differs for each connection. There is no need to
- * copy any s_data_payload stored at the original socket.
- * Failure will prevent resuming the connection.
- *
- * Presumed copied, in order of appearance:
- * cookie_in_always, cookie_out_never
- */
- if (oldcvp != NULL) {
- struct tcp_cookie_values *newcvp =
- kzalloc(sizeof(*newtp->cookie_values),
- GFP_ATOMIC);
-
- if (newcvp != NULL) {
- kref_init(&newcvp->kref);
- newcvp->cookie_desired =
- oldcvp->cookie_desired;
- newtp->cookie_values = newcvp;
- } else {
- /* Not Yet Implemented */
- newtp->cookie_values = NULL;
- }
- }
/* Now setup tcp_sock */
newtp->pred_flags = 0;
@@ -422,8 +395,7 @@
newtp->rcv_nxt = treq->rcv_isn + 1;
newtp->snd_sml = newtp->snd_una =
- newtp->snd_nxt = newtp->snd_up =
- treq->snt_isn + 1 + tcp_s_data_size(oldtp);
+ newtp->snd_nxt = newtp->snd_up = treq->snt_isn + 1;
tcp_prequeue_init(newtp);
INIT_LIST_HEAD(&newtp->tsq_node);
@@ -460,8 +432,7 @@
tcp_set_ca_state(newsk, TCP_CA_Open);
tcp_init_xmit_timers(newsk);
skb_queue_head_init(&newtp->out_of_order_queue);
- newtp->write_seq = newtp->pushed_seq =
- treq->snt_isn + 1 + tcp_s_data_size(oldtp);
+ newtp->write_seq = newtp->pushed_seq = treq->snt_isn + 1;
newtp->rx_opt.saw_tstamp = 0;
@@ -538,7 +509,6 @@
bool fastopen)
{
struct tcp_options_received tmp_opt;
- const u8 *hash_location;
struct sock *child;
const struct tcphdr *th = tcp_hdr(skb);
__be32 flg = tcp_flag_word(th) & (TCP_FLAG_RST|TCP_FLAG_SYN|TCP_FLAG_ACK);
@@ -548,7 +518,7 @@
tmp_opt.saw_tstamp = 0;
if (th->doff > (sizeof(struct tcphdr)>>2)) {
- tcp_parse_options(skb, &tmp_opt, &hash_location, 0, NULL);
+ tcp_parse_options(skb, &tmp_opt, 0, NULL);
if (tmp_opt.saw_tstamp) {
tmp_opt.ts_recent = req->ts_recent;
@@ -648,7 +618,7 @@
*/
if ((flg & TCP_FLAG_ACK) && !fastopen &&
(TCP_SKB_CB(skb)->ack_seq !=
- tcp_rsk(req)->snt_isn + 1 + tcp_s_data_size(tcp_sk(sk))))
+ tcp_rsk(req)->snt_isn + 1))
return sk;
/* Also, it would be not so bad idea to check rcv_tsecr, which