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Diffstat (limited to 'sys/netinet/cc.h')
-rw-r--r-- | sys/netinet/cc.h | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/sys/netinet/cc.h b/sys/netinet/cc.h new file mode 100644 index 0000000..6f24f11 --- /dev/null +++ b/sys/netinet/cc.h @@ -0,0 +1,161 @@ +/*- + * 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, 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'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_H_ +#define _NETINET_CC_H_ + +/* XXX: TCP_CA_NAME_MAX define lives in tcp.h for compat reasons. */ +#include <netinet/tcp.h> + +/* Global CC vars. */ +extern STAILQ_HEAD(cc_head, cc_algo) cc_list; +extern const int tcprexmtthresh; +extern struct cc_algo newreno_cc_algo; + +/* Define the new net.inet.tcp.cc sysctl tree. */ +SYSCTL_DECL(_net_inet_tcp_cc); + +/* CC housekeeping functions. */ +void cc_init(void); +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; +}; + +/* cc_var flags. */ +#define CCF_ABC_SENTAWND 0x0001 /* ABC counted cwnd worth of bytes? */ +#define CCF_CWND_LIMITED 0x0002 /* Are we currently cwnd limited? */ + +/* 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. */ + +/* + * 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 0x000001/* ECN marked packet received. */ +#define CC_RTO 0x000002/* RTO fired. */ +#define CC_RTO_ERR 0x000004/* RTO fired in error. */ +#define CC_NDUPACK 0x000008/* Threshold of dupack's reached. */ + +/* + * 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); + + 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() STAILQ_FIRST(&cc_list) + +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_WLOCK_ASSERT() rw_assert(&cc_list_lock, RA_WLOCKED) + +#endif /* _NETINET_CC_H_ */ |