xref: /freebsd/sys/netpfil/ipfw/dn_sched_rr.c (revision 8df8b2d3e51d1b816201d8a1fe8bc29fe192e562)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2010 Riccardo Panicucci, Universita` di Pisa
5  * All rights reserved
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 /*
30  * $FreeBSD$
31  */
32 
33 #ifdef _KERNEL
34 #include <sys/malloc.h>
35 #include <sys/socket.h>
36 #include <sys/socketvar.h>
37 #include <sys/kernel.h>
38 #include <sys/lock.h>
39 #include <sys/mbuf.h>
40 #include <sys/module.h>
41 #include <sys/rwlock.h>
42 #include <net/if.h>	/* IFNAMSIZ */
43 #include <netinet/in.h>
44 #include <netinet/ip_var.h>		/* ipfw_rule_ref */
45 #include <netinet/ip_fw.h>	/* flow_id */
46 #include <netinet/ip_dummynet.h>
47 #include <netpfil/ipfw/ip_fw_private.h>
48 #include <netpfil/ipfw/dn_heap.h>
49 #include <netpfil/ipfw/ip_dn_private.h>
50 #ifdef NEW_AQM
51 #include <netpfil/ipfw/dn_aqm.h>
52 #endif
53 #include <netpfil/ipfw/dn_sched.h>
54 #else
55 #include <dn_test.h>
56 #endif
57 
58 #define DN_SCHED_RR	3 // XXX Where?
59 
60 struct rr_queue {
61 	struct dn_queue q;		/* Standard queue */
62 	int status;			/* 1: queue is in the list */
63 	uint32_t credit;		/* max bytes we can transmit */
64 	uint32_t quantum;		/* quantum * weight */
65 	struct rr_queue *qnext;		/* */
66 };
67 
68 /* struct rr_schk contains global config parameters
69  * and is right after dn_schk
70  */
71 struct rr_schk {
72 	uint32_t min_q;		/* Min quantum */
73 	uint32_t max_q;		/* Max quantum */
74 	uint32_t q_bytes;	/* default quantum in bytes */
75 };
76 
77 /* per-instance round robin list, right after dn_sch_inst */
78 struct rr_si {
79 	struct rr_queue *head, *tail;	/* Pointer to current queue */
80 };
81 
82 /* Append a queue to the rr list */
83 static inline void
84 rr_append(struct rr_queue *q, struct rr_si *si)
85 {
86 	q->status = 1;		/* mark as in-rr_list */
87 	q->credit = q->quantum;	/* initialize credit */
88 
89 	/* append to the tail */
90 	if (si->head == NULL)
91 		si->head = q;
92 	else
93 		si->tail->qnext = q;
94 	si->tail = q;		/* advance the tail pointer */
95 	q->qnext = si->head;	/* make it circular */
96 }
97 
98 /* Remove the head queue from circular list. */
99 static inline void
100 rr_remove_head(struct rr_si *si)
101 {
102 	if (si->head == NULL)
103 		return; /* empty queue */
104 	si->head->status = 0;
105 
106 	if (si->head == si->tail) {
107 		si->head = si->tail = NULL;
108 		return;
109 	}
110 
111 	si->head = si->head->qnext;
112 	si->tail->qnext = si->head;
113 }
114 
115 /* Remove a queue from circular list.
116  * XXX see if ti can be merge with remove_queue()
117  */
118 static inline void
119 remove_queue_q(struct rr_queue *q, struct rr_si *si)
120 {
121 	struct rr_queue *prev;
122 
123 	if (q->status != 1)
124 		return;
125 	if (q == si->head) {
126 		rr_remove_head(si);
127 		return;
128 	}
129 
130 	for (prev = si->head; prev; prev = prev->qnext) {
131 		if (prev->qnext != q)
132 			continue;
133 		prev->qnext = q->qnext;
134 		if (q == si->tail)
135 			si->tail = prev;
136 		q->status = 0;
137 		break;
138 	}
139 }
140 
141 
142 static inline void
143 next_pointer(struct rr_si *si)
144 {
145 	if (si->head == NULL)
146 		return; /* empty queue */
147 
148 	si->head = si->head->qnext;
149 	si->tail = si->tail->qnext;
150 }
151 
152 static int
153 rr_enqueue(struct dn_sch_inst *_si, struct dn_queue *q, struct mbuf *m)
154 {
155 	struct rr_si *si;
156 	struct rr_queue *rrq;
157 
158 	if (m != q->mq.head) {
159 		if (dn_enqueue(q, m, 0)) /* packet was dropped */
160 			return 1;
161 		if (m != q->mq.head)
162 			return 0;
163 	}
164 
165 	/* If reach this point, queue q was idle */
166 	si = (struct rr_si *)(_si + 1);
167 	rrq = (struct rr_queue *)q;
168 
169 	if (rrq->status == 1) /* Queue is already in the queue list */
170 		return 0;
171 
172 	/* Insert the queue in the queue list */
173 	rr_append(rrq, si);
174 
175 	return 0;
176 }
177 
178 static struct mbuf *
179 rr_dequeue(struct dn_sch_inst *_si)
180 {
181 	/* Access scheduler instance private data */
182 	struct rr_si *si = (struct rr_si *)(_si + 1);
183 	struct rr_queue *rrq;
184 	uint64_t len;
185 
186 	while ( (rrq = si->head) ) {
187 		struct mbuf *m = rrq->q.mq.head;
188 		if ( m == NULL) {
189 			/* empty queue, remove from list */
190 			rr_remove_head(si);
191 			continue;
192 		}
193 		len = m->m_pkthdr.len;
194 
195 		if (len > rrq->credit) {
196 			/* Packet too big */
197 			rrq->credit += rrq->quantum;
198 			/* Try next queue */
199 			next_pointer(si);
200 		} else {
201 			rrq->credit -= len;
202 			return dn_dequeue(&rrq->q);
203 		}
204 	}
205 
206 	/* no packet to dequeue*/
207 	return NULL;
208 }
209 
210 static int
211 rr_config(struct dn_schk *_schk)
212 {
213 	struct rr_schk *schk = (struct rr_schk *)(_schk + 1);
214 	ND("called");
215 
216 	/* use reasonable quantums (64..2k bytes, default 1500) */
217 	schk->min_q = 64;
218 	schk->max_q = 2048;
219 	schk->q_bytes = 1500;	/* quantum */
220 
221 	return 0;
222 }
223 
224 static int
225 rr_new_sched(struct dn_sch_inst *_si)
226 {
227 	struct rr_si *si = (struct rr_si *)(_si + 1);
228 
229 	ND("called");
230 	si->head = si->tail = NULL;
231 
232 	return 0;
233 }
234 
235 static int
236 rr_free_sched(struct dn_sch_inst *_si)
237 {
238 	(void)_si;
239 	ND("called");
240 	/* Nothing to do? */
241 	return 0;
242 }
243 
244 static int
245 rr_new_fsk(struct dn_fsk *fs)
246 {
247 	struct rr_schk *schk = (struct rr_schk *)(fs->sched + 1);
248 	/* par[0] is the weight, par[1] is the quantum step */
249 	/* make sure the product fits an uint32_t */
250 	ipdn_bound_var(&fs->fs.par[0], 1,
251 		1, 65536, "RR weight");
252 	ipdn_bound_var(&fs->fs.par[1], schk->q_bytes,
253 		schk->min_q, schk->max_q, "RR quantum");
254 	return 0;
255 }
256 
257 static int
258 rr_new_queue(struct dn_queue *_q)
259 {
260 	struct rr_queue *q = (struct rr_queue *)_q;
261 	uint64_t quantum;
262 
263 	_q->ni.oid.subtype = DN_SCHED_RR;
264 
265 	quantum = (uint64_t)_q->fs->fs.par[0] * _q->fs->fs.par[1];
266 	if (quantum >= (1ULL<< 32)) {
267 		D("quantum too large, truncating to 4G - 1");
268 		quantum = (1ULL<< 32) - 1;
269 	}
270 	q->quantum = quantum;
271 	ND("called, q->quantum %d", q->quantum);
272 	q->credit = q->quantum;
273 	q->status = 0;
274 
275 	if (_q->mq.head != NULL) {
276 		/* Queue NOT empty, insert in the queue list */
277 		rr_append(q, (struct rr_si *)(_q->_si + 1));
278 	}
279 	return 0;
280 }
281 
282 static int
283 rr_free_queue(struct dn_queue *_q)
284 {
285 	struct rr_queue *q = (struct rr_queue *)_q;
286 
287 	ND("called");
288 	if (q->status == 1) {
289 		struct rr_si *si = (struct rr_si *)(_q->_si + 1);
290 		remove_queue_q(q, si);
291 	}
292 	return 0;
293 }
294 
295 /*
296  * RR scheduler descriptor
297  * contains the type of the scheduler, the name, the size of the
298  * structures and function pointers.
299  */
300 static struct dn_alg rr_desc = {
301 	_SI( .type = ) DN_SCHED_RR,
302 	_SI( .name = ) "RR",
303 	_SI( .flags = ) DN_MULTIQUEUE,
304 
305 	_SI( .schk_datalen = ) sizeof(struct rr_schk),
306 	_SI( .si_datalen = ) sizeof(struct rr_si),
307 	_SI( .q_datalen = ) sizeof(struct rr_queue) - sizeof(struct dn_queue),
308 
309 	_SI( .enqueue = ) rr_enqueue,
310 	_SI( .dequeue = ) rr_dequeue,
311 
312 	_SI( .config = ) rr_config,
313 	_SI( .destroy = ) NULL,
314 	_SI( .new_sched = ) rr_new_sched,
315 	_SI( .free_sched = ) rr_free_sched,
316 	_SI( .new_fsk = ) rr_new_fsk,
317 	_SI( .free_fsk = ) NULL,
318 	_SI( .new_queue = ) rr_new_queue,
319 	_SI( .free_queue = ) rr_free_queue,
320 #ifdef NEW_AQM
321 	_SI( .getconfig = )  NULL,
322 #endif
323 };
324 
325 
326 DECLARE_DNSCHED_MODULE(dn_rr, &rr_desc);
327