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tcp: Remove TCPCT

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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>
This commit is contained in:
Christoph Paasch
2013-03-17 08:23:34 +00:00
committed by David S. Miller
parent 94d8f2b133
commit 1a2c6181c4
18 changed files with 37 additions and 840 deletions
Download Patch File Download Diff File Expand all files Collapse all files

60
net/ipv4/tcp_ipv4.c
View File

@@ -838,7 +838,6 @@ static void tcp_v4_reqsk_send_ack(struct sock *sk, struct sk_buff *skb,
*/
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 @@ static int tcp_v4_send_synack(struct sock *sk, struct dst_entry *dst,
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 @@ static int tcp_v4_send_synack(struct sock *sk, struct dst_entry *dst,
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 bool tcp_fastopen_check(struct sock *sk, struct sk_buff *skb,
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 @@ static int tcp_v4_conn_req_fastopen(struct sock *sk,
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 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
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 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
* 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 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
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 @@ void tcp_v4_destroy_sock(struct sock *sk)
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 */