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 75