android_kernel_motorola_sm6225/include/net/tcp_ecn.h
Arnaldo Carvalho de Melo 2e6599cb89 [NET] Generalise TCP's struct open_request minisock infrastructure
Kept this first changeset minimal, without changing existing names to
ease peer review.

Basicaly tcp_openreq_alloc now receives the or_calltable, that in turn
has two new members:

->slab, that replaces tcp_openreq_cachep
->obj_size, to inform the size of the openreq descendant for
  a specific protocol

The protocol specific fields in struct open_request were moved to a
class hierarchy, with the things that are common to all connection
oriented PF_INET protocols in struct inet_request_sock, the TCP ones
in tcp_request_sock, that is an inet_request_sock, that is an
open_request.

I.e. this uses the same approach used for the struct sock class
hierarchy, with sk_prot indicating if the protocol wants to use the
open_request infrastructure by filling in sk_prot->rsk_prot with an
or_calltable.

Results? Performance is improved and TCP v4 now uses only 64 bytes per
open request minisock, down from 96 without this patch :-)

Next changeset will rename some of the structs, fields and functions
mentioned above, struct or_calltable is way unclear, better name it
struct request_sock_ops, s/struct open_request/struct request_sock/g,
etc.

Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-18 22:46:52 -07:00

127 lines
3.2 KiB
C

#ifndef _NET_TCP_ECN_H_
#define _NET_TCP_ECN_H_ 1
#include <net/inet_ecn.h>
#include <net/request_sock.h>
#define TCP_HP_BITS (~(TCP_RESERVED_BITS|TCP_FLAG_PSH))
#define TCP_ECN_OK 1
#define TCP_ECN_QUEUE_CWR 2
#define TCP_ECN_DEMAND_CWR 4
static inline void TCP_ECN_queue_cwr(struct tcp_sock *tp)
{
if (tp->ecn_flags&TCP_ECN_OK)
tp->ecn_flags |= TCP_ECN_QUEUE_CWR;
}
/* Output functions */
static inline void TCP_ECN_send_synack(struct tcp_sock *tp,
struct sk_buff *skb)
{
TCP_SKB_CB(skb)->flags &= ~TCPCB_FLAG_CWR;
if (!(tp->ecn_flags&TCP_ECN_OK))
TCP_SKB_CB(skb)->flags &= ~TCPCB_FLAG_ECE;
}
static inline void TCP_ECN_send_syn(struct sock *sk, struct tcp_sock *tp,
struct sk_buff *skb)
{
tp->ecn_flags = 0;
if (sysctl_tcp_ecn && !(sk->sk_route_caps & NETIF_F_TSO)) {
TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_ECE|TCPCB_FLAG_CWR;
tp->ecn_flags = TCP_ECN_OK;
sock_set_flag(sk, SOCK_NO_LARGESEND);
}
}
static __inline__ void
TCP_ECN_make_synack(struct open_request *req, struct tcphdr *th)
{
if (inet_rsk(req)->ecn_ok)
th->ece = 1;
}
static inline void TCP_ECN_send(struct sock *sk, struct tcp_sock *tp,
struct sk_buff *skb, int tcp_header_len)
{
if (tp->ecn_flags & TCP_ECN_OK) {
/* Not-retransmitted data segment: set ECT and inject CWR. */
if (skb->len != tcp_header_len &&
!before(TCP_SKB_CB(skb)->seq, tp->snd_nxt)) {
INET_ECN_xmit(sk);
if (tp->ecn_flags&TCP_ECN_QUEUE_CWR) {
tp->ecn_flags &= ~TCP_ECN_QUEUE_CWR;
skb->h.th->cwr = 1;
}
} else {
/* ACK or retransmitted segment: clear ECT|CE */
INET_ECN_dontxmit(sk);
}
if (tp->ecn_flags & TCP_ECN_DEMAND_CWR)
skb->h.th->ece = 1;
}
}
/* Input functions */
static inline void TCP_ECN_accept_cwr(struct tcp_sock *tp, struct sk_buff *skb)
{
if (skb->h.th->cwr)
tp->ecn_flags &= ~TCP_ECN_DEMAND_CWR;
}
static inline void TCP_ECN_withdraw_cwr(struct tcp_sock *tp)
{
tp->ecn_flags &= ~TCP_ECN_DEMAND_CWR;
}
static inline void TCP_ECN_check_ce(struct tcp_sock *tp, struct sk_buff *skb)
{
if (tp->ecn_flags&TCP_ECN_OK) {
if (INET_ECN_is_ce(TCP_SKB_CB(skb)->flags))
tp->ecn_flags |= TCP_ECN_DEMAND_CWR;
/* Funny extension: if ECT is not set on a segment,
* it is surely retransmit. It is not in ECN RFC,
* but Linux follows this rule. */
else if (INET_ECN_is_not_ect((TCP_SKB_CB(skb)->flags)))
tcp_enter_quickack_mode(tp);
}
}
static inline void TCP_ECN_rcv_synack(struct tcp_sock *tp, struct tcphdr *th)
{
if ((tp->ecn_flags&TCP_ECN_OK) && (!th->ece || th->cwr))
tp->ecn_flags &= ~TCP_ECN_OK;
}
static inline void TCP_ECN_rcv_syn(struct tcp_sock *tp, struct tcphdr *th)
{
if ((tp->ecn_flags&TCP_ECN_OK) && (!th->ece || !th->cwr))
tp->ecn_flags &= ~TCP_ECN_OK;
}
static inline int TCP_ECN_rcv_ecn_echo(struct tcp_sock *tp, struct tcphdr *th)
{
if (th->ece && !th->syn && (tp->ecn_flags&TCP_ECN_OK))
return 1;
return 0;
}
static inline void TCP_ECN_openreq_child(struct tcp_sock *tp,
struct open_request *req)
{
tp->ecn_flags = inet_rsk(req)->ecn_ok ? TCP_ECN_OK : 0;
}
static __inline__ void
TCP_ECN_create_request(struct open_request *req, struct tcphdr *th)
{
if (sysctl_tcp_ecn && th->ece && th->cwr)
inet_rsk(req)->ecn_ok = 1;
}
#endif