NetBSD/sys/netinet/tcp_congctl.h

97 lines
3.4 KiB
C

/* $NetBSD: tcp_congctl.h,v 1.6 2011/04/14 15:57:02 yamt Exp $ */
/*
* Copyright (c) 2006 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Rui Paulo.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _NETINET_TCP_CONGCTL_H
#define _NETINET_TCP_CONGCTL_H
#define TCPCC_MAXLEN 12
struct tcp_congctlent {
TAILQ_ENTRY(tcp_congctlent) congctl_ent;
const struct tcp_congctl *congctl_ctl;
unsigned int congctl_refcnt;
char congctl_name[TCPCC_MAXLEN];
};
/*
* Congestion control function table.
*/
struct tcp_congctl {
/*
* fast_retransmit: called on tcprexmtthresh'th dup ACKs.
* this actually retransmits packets by calling tcp_output()
* if appropriate.
* returns 0 if entering fast recovery. otherwise returns non-0.
*/
int (*fast_retransmit)(struct tcpcb *, const struct tcphdr *);
/*
* slow_retransmit: called on RTO to adjust parameters like cwnd.
*/
void (*slow_retransmit)(struct tcpcb *);
/*
* fast_retransmit_newack: called when new data is acked.
* ie. when advancing SND.UNA
* not called if TCP_SACK_ENABLED.
*/
void (*fast_retransmit_newack)(struct tcpcb *, const struct tcphdr *);
/*
* newack: called when new data is acked. ie. when advancing SND.UNA
* it's called before updating tp->snd_una.
*/
void (*newack)(struct tcpcb *, const struct tcphdr *);
/*
* cong_exp: called when congestion is detected. eg. by ECN
*/
void (*cong_exp)(struct tcpcb *);
};
extern const struct tcp_congctl tcp_reno_ctl;
extern const struct tcp_congctl tcp_newreno_ctl;
/* currently selected global congestion control */
extern char tcp_congctl_global_name[TCPCC_MAXLEN];
/* available global congestion control algorithms */
extern char tcp_congctl_avail[10 * TCPCC_MAXLEN];
void tcp_congctl_init(void);
int tcp_congctl_register(const char *, const struct tcp_congctl *);
int tcp_congctl_unregister(const char *);
int tcp_congctl_select(struct tcpcb *, const char *);
void tcp_congctl_release(struct tcpcb *);
const char *
tcp_congctl_bystruct(const struct tcp_congctl *);
#endif /* _NETINET_TCP_CONGCTL_H */