altq_codel.h revision 298133 
1/*
2 * CoDel - The Controlled-Delay Active Queue Management algorithm
3 *
4 *  Copyright (C) 2013 Ermal Lu��i <eri@FreeBSD.org>
5 *  Copyright (C) 2011-2012 Kathleen Nichols <nichols@pollere.com>
6 *  Copyright (C) 2011-2012 Van Jacobson <van@pollere.net>
7 *  Copyright (C) 2012 Michael D. Taht <dave.taht@bufferbloat.net>
8 *  Copyright (C) 2012 Eric Dumazet <edumazet@google.com>
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions, and the following disclaimer,
15 *    without modification.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 * 3. The names of the authors may not be used to endorse or promote products
20 *    derived from this software without specific prior written permission.
21 *
22 * Alternatively, provided that this notice is retained in full, this
23 * software may be distributed under the terms of the GNU General
24 * Public License ("GPL") version 2, in which case the provisions of the
25 * GPL apply INSTEAD OF those given above.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
30 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
31 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
32 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
33 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
34 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
35 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
36 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
37 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
38 * DAMAGE.
39 *
40 * $FreeBSD: stable/10/sys/contrib/altq/altq/altq_codel.h 298133 2016-04-16 22:02:32Z loos $
41 */
42
43#ifndef _ALTQ_ALTQ_CODEL_H_
44#define	_ALTQ_ALTQ_CODEL_H_
45
46struct codel_stats {
47	u_int32_t	maxpacket;
48	struct pktcntr	drop_cnt;
49	u_int		marked_packets;
50};
51
52struct codel_ifstats {
53	u_int			qlength;
54	u_int			qlimit;
55	struct codel_stats	stats;
56	struct pktcntr	cl_xmitcnt;	/* transmitted packet counter */
57	struct pktcntr	cl_dropcnt;	/* dropped packet counter */
58};
59
60#ifdef _KERNEL
61#include <altq/altq_classq.h>
62
63/**
64 * struct codel_params - contains codel parameters
65 *  <at> target:	target queue size (in time units)
66 *  <at> interval:	width of moving time window
67 *  <at> ecn:	is Explicit Congestion Notification enabled
68 */
69struct codel_params {
70	u_int64_t	target;
71	u_int64_t	interval;
72	int		ecn;
73};
74
75/**
76 * struct codel_vars - contains codel variables
77 *  <at> count:		how many drops we've done since the last time we
78 *			entered dropping state
79 *  <at> lastcount:	count at entry to dropping state
80 *  <at> dropping:	set to true if in dropping state
81 *  <at> rec_inv_sqrt:	reciprocal value of sqrt(count) >> 1
82 *  <at> first_above_time:	when we went (or will go) continuously above
83 *				target for interval
84 *  <at> drop_next:	time to drop next packet, or when we dropped last
85 *  <at> ldelay:	sojourn time of last dequeued packet
86 */
87struct codel_vars {
88	u_int32_t	count;
89	u_int32_t	lastcount;
90	int		dropping;
91	u_int16_t	rec_inv_sqrt;
92	u_int64_t	first_above_time;
93	u_int64_t	drop_next;
94	u_int64_t	ldelay;
95};
96
97struct codel {
98	int			last_pps;
99	struct codel_params	params;
100	struct codel_vars	vars;
101	struct codel_stats	stats;
102	struct timeval		last_log;
103	u_int32_t		drop_overlimit;
104};
105
106/*
107 * codel interface state
108 */
109struct codel_if {
110	struct codel_if		*cif_next;	/* interface state list */
111	struct ifaltq		*cif_ifq;	/* backpointer to ifaltq */
112	u_int			cif_bandwidth;	/* link bandwidth in bps */
113
114	class_queue_t	*cl_q;		/* class queue structure */
115	struct codel	codel;
116
117	/* statistics */
118	struct codel_ifstats cl_stats;
119};
120
121struct codel	*codel_alloc(int, int, int);
122void		 codel_destroy(struct codel *);
123int		 codel_addq(struct codel *, class_queue_t *, struct mbuf *);
124struct mbuf	*codel_getq(struct codel *, class_queue_t *);
125void		 codel_getstats(struct codel *, struct codel_stats *);
126
127#endif /* _KERNEL */
128
129#endif /* _ALTQ_ALTQ_CODEL_H_ */
130