xref: /freebsd/sys/netpfil/ipfw/dn_sched_fq_codel.h (revision dd41de95a84d979615a2ef11df6850622bf6184e)
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  * $FreeBSD$
34  */
35 
36 #ifndef _IP_DN_SCHED_FQ_CODEL_H
37 #define _IP_DN_SCHED_FQ_CODEL_H
38 
39 /* list of queues */
40 STAILQ_HEAD(fq_codel_list, fq_codel_flow) ;
41 
42 /* fq_codel parameters including codel */
43 struct 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 */
52 struct 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).*/
61 struct 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 */
71 struct fq_codel_schk {
72 	struct dn_sch_fq_codel_parms cfg;
73 };
74 
75 /* fq_codel scheduler instance */
76 struct 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
93 fq_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 		dn_cfg.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 *
139 fq_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 #endif
167