aboutsummaryrefslogtreecommitdiff
path: root/sys/netinet/cc/cc.h
blob: be84a6841d15569e65d7cd784239dc745155a968 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
/*-
 * Copyright (c) 2007-2008
 * 	Swinburne University of Technology, Melbourne, Australia.
 * Copyright (c) 2009-2010 Lawrence Stewart <lstewart@freebsd.org>
 * Copyright (c) 2010 The FreeBSD Foundation
 * All rights reserved.
 *
 * This software was developed at the Centre for Advanced Internet
 * Architectures, Swinburne University of Technology, by Lawrence Stewart and
 * James Healy, made possible in part by a grant from the Cisco University
 * Research Program Fund at Community Foundation Silicon Valley.
 *
 * Portions of this software were developed at the Centre for Advanced
 * Internet Architectures, Swinburne University of Technology, Melbourne,
 * Australia by David Hayes under sponsorship from the FreeBSD Foundation.
 *
 * 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 AUTHOR 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 AUTHOR 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.
 *
 * $FreeBSD$
 */

/*
 * This software was first released in 2007 by James Healy and Lawrence Stewart
 * whilst working on the NewTCP research project at Swinburne University of
 * Technology's Centre for Advanced Internet Architectures, Melbourne,
 * Australia, which was made possible in part by a grant from the Cisco
 * University Research Program Fund at Community Foundation Silicon Valley.
 * More details are available at:
 *   http://caia.swin.edu.au/urp/newtcp/
 */

#ifndef _NETINET_CC_CC_H_
#define _NETINET_CC_CC_H_

#ifdef _KERNEL

/* Global CC vars. */
extern STAILQ_HEAD(cc_head, cc_algo) cc_list;
extern const int tcprexmtthresh;
extern struct cc_algo newreno_cc_algo;

/* Per-netstack bits. */
VNET_DECLARE(struct cc_algo *, default_cc_ptr);
#define	V_default_cc_ptr VNET(default_cc_ptr)

VNET_DECLARE(int, cc_do_abe);
#define	V_cc_do_abe			VNET(cc_do_abe)

VNET_DECLARE(int, cc_abe_frlossreduce);
#define	V_cc_abe_frlossreduce		VNET(cc_abe_frlossreduce)

/* Define the new net.inet.tcp.cc sysctl tree. */
SYSCTL_DECL(_net_inet_tcp_cc);

/* CC housekeeping functions. */
int	cc_register_algo(struct cc_algo *add_cc);
int	cc_deregister_algo(struct cc_algo *remove_cc);

/*
 * Wrapper around transport structs that contain same-named congestion
 * control variables. Allows algos to be shared amongst multiple CC aware
 * transprots.
 */
struct cc_var {
	void		*cc_data; /* Per-connection private CC algorithm data. */
	int		bytes_this_ack; /* # bytes acked by the current ACK. */
	tcp_seq		curack; /* Most recent ACK. */
	uint32_t	flags; /* Flags for cc_var (see below) */
	int		type; /* Indicates which ptr is valid in ccvc. */
	union ccv_container {
		struct tcpcb		*tcp;
		struct sctp_nets	*sctp;
	} ccvc;
	uint16_t	nsegs; /* # segments coalesced into current chain. */
	uint8_t		labc;  /* Dont use system abc use passed in */
};

/* cc_var flags. */
#define	CCF_ABC_SENTAWND	0x0001	/* ABC counted cwnd worth of bytes? */
#define	CCF_CWND_LIMITED	0x0002	/* Are we currently cwnd limited? */
#define	CCF_USE_LOCAL_ABC       0x0004  /* Dont use the system l_abc val */
#define	CCF_ACKNOW		0x0008	/* Will this ack be sent now? */
#define	CCF_IPHDR_CE		0x0010	/* Does this packet set CE bit? */
#define	CCF_TCPHDR_CWR		0x0020	/* Does this packet set CWR bit? */
#define	CCF_MAX_CWND		0x0040	/* Have we reached maximum cwnd? */
#define	CCF_CHG_MAX_CWND	0x0080	/* Cubic max_cwnd changed, for K */
#define	CCF_USR_IWND		0x0100	/* User specified initial window */
#define	CCF_USR_IWND_INIT_NSEG	0x0200	/* Convert segs to bytes on conn init */

/* ACK types passed to the ack_received() hook. */
#define	CC_ACK		0x0001	/* Regular in sequence ACK. */
#define	CC_DUPACK	0x0002	/* Duplicate ACK. */
#define	CC_PARTIALACK	0x0004	/* Not yet. */
#define	CC_SACK		0x0008	/* Not yet. */
#endif /* _KERNEL */

/*
 * Congestion signal types passed to the cong_signal() hook. The highest order 8
 * bits (0x01000000 - 0x80000000) are reserved for CC algos to declare their own
 * congestion signal types.
 */
#define	CC_ECN		0x00000001	/* ECN marked packet received. */
#define	CC_RTO		0x00000002	/* RTO fired. */
#define	CC_RTO_ERR	0x00000004	/* RTO fired in error. */
#define	CC_NDUPACK	0x00000008	/* Threshold of dupack's reached. */

#define	CC_SIGPRIVMASK	0xFF000000	/* Mask to check if sig is private. */

#ifdef _KERNEL
/*
 * Structure to hold data and function pointers that together represent a
 * congestion control algorithm.
 */
struct cc_algo {
	char	name[TCP_CA_NAME_MAX];

	/* Init global module state on kldload. */
	int	(*mod_init)(void);

	/* Cleanup global module state on kldunload. */
	int	(*mod_destroy)(void);

	/* Init CC state for a new control block. */
	int	(*cb_init)(struct cc_var *ccv);

	/* Cleanup CC state for a terminating control block. */
	void	(*cb_destroy)(struct cc_var *ccv);

	/* Init variables for a newly established connection. */
	void	(*conn_init)(struct cc_var *ccv);

	/* Called on receipt of an ack. */
	void	(*ack_received)(struct cc_var *ccv, uint16_t type);

	/* Called on detection of a congestion signal. */
	void	(*cong_signal)(struct cc_var *ccv, uint32_t type);

	/* Called after exiting congestion recovery. */
	void	(*post_recovery)(struct cc_var *ccv);

	/* Called when data transfer resumes after an idle period. */
	void	(*after_idle)(struct cc_var *ccv);

	/* Called for an additional ECN processing apart from RFC3168. */
	void	(*ecnpkt_handler)(struct cc_var *ccv);

	/* Called for {get|set}sockopt() on a TCP socket with TCP_CCALGOOPT. */
	int     (*ctl_output)(struct cc_var *, struct sockopt *, void *);

	STAILQ_ENTRY (cc_algo) entries;
};

/* Macro to obtain the CC algo's struct ptr. */
#define	CC_ALGO(tp)	((tp)->cc_algo)

/* Macro to obtain the CC algo's data ptr. */
#define	CC_DATA(tp)	((tp)->ccv->cc_data)

/* Macro to obtain the system default CC algo's struct ptr. */
#define	CC_DEFAULT()	V_default_cc_ptr

extern struct rwlock cc_list_lock;
#define	CC_LIST_LOCK_INIT()	rw_init(&cc_list_lock, "cc_list")
#define	CC_LIST_LOCK_DESTROY()	rw_destroy(&cc_list_lock)
#define	CC_LIST_RLOCK()		rw_rlock(&cc_list_lock)
#define	CC_LIST_RUNLOCK()	rw_runlock(&cc_list_lock)
#define	CC_LIST_WLOCK()		rw_wlock(&cc_list_lock)
#define	CC_LIST_WUNLOCK()	rw_wunlock(&cc_list_lock)
#define	CC_LIST_LOCK_ASSERT()	rw_assert(&cc_list_lock, RA_LOCKED)

#define CC_ALGOOPT_LIMIT	2048

#endif /* _KERNEL */
#endif /* _NETINET_CC_CC_H_ */