1 #ifndef __NET_SCHED_CODEL_QDISC_H
2 #define __NET_SCHED_CODEL_QDISC_H
3
4 /*
5 * Codel - The Controlled-Delay Active Queue Management algorithm
6 *
7 * Copyright (C) 2011-2012 Kathleen Nichols <nichols@pollere.com>
8 * Copyright (C) 2011-2012 Van Jacobson <van@pollere.net>
9 * Copyright (C) 2012 Michael D. Taht <dave.taht@bufferbloat.net>
10 * Copyright (C) 2012,2015 Eric Dumazet <edumazet@google.com>
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions, and the following disclaimer,
17 * without modification.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. The names of the authors may not be used to endorse or promote products
22 * derived from this software without specific prior written permission.
23 *
24 * Alternatively, provided that this notice is retained in full, this
25 * software may be distributed under the terms of the GNU General
26 * Public License ("GPL") version 2, in which case the provisions of the
27 * GPL apply INSTEAD OF those given above.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
30 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
31 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
32 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
33 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
34 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
35 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
39 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
40 * DAMAGE.
41 *
42 */
43
44 /* Controlling Queue Delay (CoDel) algorithm
45 * =========================================
46 * Source : Kathleen Nichols and Van Jacobson
47 * http://queue.acm.org/detail.cfm?id=2209336
48 *
49 * Implemented on linux by Dave Taht and Eric Dumazet
50 */
51
52 /* Qdiscs using codel plugin must use codel_skb_cb in their own cb[] */
53 struct codel_skb_cb {
54 codel_time_t enqueue_time;
55 unsigned int mem_usage;
56 };
57
58 static struct codel_skb_cb *get_codel_cb(const struct sk_buff *skb)
59 {
60 qdisc_cb_private_validate(skb, sizeof(struct codel_skb_cb));
61 return (struct codel_skb_cb *)qdisc_skb_cb(skb)->data;
62 }
63
64 static codel_time_t codel_get_enqueue_time(const struct sk_buff *skb)
65 {
66 return get_codel_cb(skb)->enqueue_time;
67 }
68
69 static void codel_set_enqueue_time(struct sk_buff *skb)
70 {
71 get_codel_cb(skb)->enqueue_time = codel_get_time();
72 }
73
74 #endif