1/*-
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>
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
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.
16 *
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
27 * SUCH DAMAGE.
28 */
29
30/*
31 * FQ_Codel Structures and helper functions
32 *
33 * $FreeBSD: releng/11.0/sys/netpfil/ipfw/dn_sched_fq_codel.h 300779 2016-05-26 21:40:13Z truckman $
34 */
35
36#ifndef _IP_DN_SCHED_FQ_CODEL_H
37#define _IP_DN_SCHED_FQ_CODEL_H
38
39/* list of queues */
40STAILQ_HEAD(fq_codel_list, fq_codel_flow) ;
41
42/* fq_codel parameters including codel */
43struct dn_sch_fq_codel_parms {
44	struct dn_aqm_codel_parms	ccfg;	/* CoDel Parameters */
45	/* FQ_CODEL Parameters */
46	uint32_t flows_cnt;	/* number of flows */
47	uint32_t limit;	/* hard limit of fq_codel queue size*/
48	uint32_t quantum;
49};	/* defaults */
50
51/* flow (sub-queue) stats */
52struct flow_stats {
53	uint64_t tot_pkts;	/* statistics counters  */
54	uint64_t tot_bytes;
55	uint32_t length;		/* Queue length, in packets */
56	uint32_t len_bytes;	/* Queue length, in bytes */
57	uint32_t drops;
58};
59
60/* A flow of packets (sub-queue).*/
61struct fq_codel_flow {
62	struct mq	mq;	/* list of packets */
63	struct flow_stats stats;	/* statistics */
64	int	deficit;
65	int active;		/* 1: flow is active (in a list) */
66	struct codel_status cst;
67	STAILQ_ENTRY(fq_codel_flow) flowchain;
68};
69
70/* extra fq_codel scheduler configurations */
71struct fq_codel_schk {
72	struct dn_sch_fq_codel_parms cfg;
73};
74
75/* fq_codel scheduler instance */
76struct fq_codel_si {
77	struct dn_sch_inst _si;	/* standard scheduler instance */
78	struct dn_queue main_q; /* main queue is after si directly */
79
80	struct fq_codel_flow *flows; /* array of flows (queues) */
81	uint32_t perturbation; /* random value */
82	struct fq_codel_list newflows;	/* list of new queues */
83	struct fq_codel_list oldflows;		/* list of old queues */
84};
85
86/* Helper function to update queue&main-queue and scheduler statistics.
87 * negative len + drop -> drop
88 * negative len -> dequeue
89 * positive len -> enqueue
90 * positive len + drop -> drop during enqueue
91 */
92__inline static void
93fq_update_stats(struct fq_codel_flow *q, struct fq_codel_si *si, int len,
94	int drop)
95{
96	int inc = 0;
97
98	if (len < 0)
99		inc = -1;
100	else if (len > 0)
101		inc = 1;
102
103	if (drop) {
104		si->main_q.ni.drops ++;
105		q->stats.drops ++;
106		si->_si.ni.drops ++;
107		io_pkt_drop ++;
108	}
109
110	if (!drop || (drop && len < 0)) {
111		/* Update stats for the main queue */
112		si->main_q.ni.length += inc;
113		si->main_q.ni.len_bytes += len;
114
115		/*update sub-queue stats */
116		q->stats.length += inc;
117		q->stats.len_bytes += len;
118
119		/*update scheduler instance stats */
120		si->_si.ni.length += inc;
121		si->_si.ni.len_bytes += len;
122	}
123
124	if (inc > 0) {
125		si->main_q.ni.tot_bytes += len;
126		si->main_q.ni.tot_pkts ++;
127
128		q->stats.tot_bytes +=len;
129		q->stats.tot_pkts++;
130
131		si->_si.ni.tot_bytes +=len;
132		si->_si.ni.tot_pkts ++;
133	}
134
135}
136
137/* extract the head of fq_codel sub-queue */
138__inline static struct mbuf *
139fq_codel_extract_head(struct fq_codel_flow *q, aqm_time_t *pkt_ts, struct fq_codel_si *si)
140{
141	struct mbuf *m = q->mq.head;
142
143	if (m == NULL)
144		return m;
145	q->mq.head = m->m_nextpkt;
146
147	fq_update_stats(q, si, -m->m_pkthdr.len, 0);
148
149	if (si->main_q.ni.length == 0) /* queue is now idle */
150			si->main_q.q_time = dn_cfg.curr_time;
151
152	/* extract packet timestamp*/
153	struct m_tag *mtag;
154	mtag = m_tag_locate(m, MTAG_ABI_COMPAT, DN_AQM_MTAG_TS, NULL);
155	if (mtag == NULL){
156		D("timestamp tag is not found!");
157		*pkt_ts = 0;
158	} else {
159		*pkt_ts = *(aqm_time_t *)(mtag + 1);
160		m_tag_delete(m,mtag);
161	}
162
163	return m;
164}
165
166
167#endif
168