2 * Copyright (C) 2016 Centre for Advanced Internet Architectures,
3 * Swinburne University of Technology, Melbourne, Australia.
4 * Portions of this code were made possible in part by a gift from
5 * The Comcast Innovation Fund.
6 * Implemented by Rasool Al-Saadi <ralsaadi@swin.edu.au>
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * API for writing an Active Queue Management algorithm for Dummynet
39 /* NOW is the current time in millisecond*/
40 #define NOW ((dn_cfg.curr_time * tick) / 1000)
42 #define AQM_UNOW (dn_cfg.curr_time * tick)
43 #define AQM_TIME_1US ((aqm_time_t)(1))
44 #define AQM_TIME_1MS ((aqm_time_t)(1000))
45 #define AQM_TIME_1S ((aqm_time_t)(AQM_TIME_1MS * 1000))
47 /* aqm time allows to store up to 4294 seconds */
48 typedef uint32_t aqm_time_t;
49 typedef int32_t aqm_stime_t;
51 #define DN_AQM_MTAG_TS 55345
53 /* Macro for variable bounding */
54 #define BOUND_VAR(x,l,h) ((x) > (h)? (h) : ((x) > (l)? (x) : (l)))
56 /* sysctl variable to count number of dropped packets */
57 extern unsigned long io_pkt_drop;
60 * Structure for holding data and function pointers that together represent a
64 #define DN_AQM_NAME_MAX 50
65 char name[DN_AQM_NAME_MAX]; /* name of AQM algorithm */
66 uint32_t type; /* AQM type number */
68 /* Methods implemented by AQM algorithm:
70 * enqueue enqueue packet 'm' on queue 'q'.
71 * Return 0 on success, 1 on drop.
73 * dequeue dequeue a packet from queue 'q'.
74 * Return a packet, NULL if no packet available.
76 * config configure AQM algorithm
77 * If required, this function should allocate space to store
78 * the configurations and set 'fs->aqmcfg' to point to this space.
79 * 'dn_extra_parms' includes array of parameters send
80 * from ipfw userland command.
81 * Return 0 on success, non-zero otherwise.
83 * deconfig deconfigure AQM algorithm.
84 * The allocated configuration memory space should be freed here.
85 * Return 0 on success, non-zero otherwise.
87 * init initialise AQM status variables of queue 'q'
88 * This function is used to allocate space and init AQM status for a
89 * queue and q->aqm_status to point to this space.
90 * Return 0 on success, non-zero otherwise.
92 * cleanup cleanup AQM status variables of queue 'q'
93 * The allocated memory space for AQM status should be freed here.
94 * Return 0 on success, non-zero otherwise.
96 * getconfig retrieve AQM configurations
97 * This function is used to return AQM parameters to userland
98 * command. The function should fill 'dn_extra_parms' struct with
99 * the AQM configurations using 'par' array.
103 int (*enqueue)(struct dn_queue *, struct mbuf *);
104 struct mbuf * (*dequeue)(struct dn_queue *);
105 int (*config)(struct dn_fsk *, struct dn_extra_parms *ep, int);
106 int (*deconfig)(struct dn_fsk *);
107 int (*init)(struct dn_queue *);
108 int (*cleanup)(struct dn_queue *);
109 int (*getconfig)(struct dn_fsk *, struct dn_extra_parms *);
111 int ref_count; /*Number of queues instances in the system */
112 int cfg_ref_count; /*Number of AQM instances in the system */
113 SLIST_ENTRY (dn_aqm) next; /* Next AQM in the list */
116 /* Helper function to update queue and scheduler statistics.
117 * negative len + drop -> drop
118 * negative len -> dequeue
119 * positive len -> enqueue
120 * positive len + drop -> drop during enqueue
123 update_stats(struct dn_queue *q, int len, int drop)
142 /*update queue stats */
144 qni->len_bytes += len;
146 /*update scheduler instance stats */
148 sni->len_bytes += len;
150 /* tot_pkts is updated in dn_enqueue function */
153 /* kernel module related function */
155 dn_aqm_modevent(module_t mod, int cmd, void *arg);
157 #define DECLARE_DNAQM_MODULE(name, dnaqm) \
158 static moduledata_t name##_mod = { \
159 #name, dn_aqm_modevent, dnaqm \
161 DECLARE_MODULE(name, name##_mod, \
162 SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY); \
163 MODULE_DEPEND(name, dummynet, 3, 3, 3)