1/*-
2 * Copyright (c) 2001 Jake Burkholder <jake@FreeBSD.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD$
27 */
28
29#ifndef	_RUNQ_H_
30#define	_RUNQ_H_
31
32#include <machine/runq.h>
33
34struct thread;
35
36/*
37 * Run queue parameters.
38 */
39
40#define	RQ_NQS		(64)		/* Number of run queues. */
41#define	RQ_PPQ		(4)		/* Priorities per queue. */
42
43/*
44 * Head of run queues.
45 */
46TAILQ_HEAD(rqhead, thread);
47
48/*
49 * Bit array which maintains the status of a run queue.  When a queue is
50 * non-empty the bit corresponding to the queue number will be set.
51 */
52struct rqbits {
53	rqb_word_t rqb_bits[RQB_LEN];
54};
55
56/*
57 * Run queue structure.  Contains an array of run queues on which processes
58 * are placed, and a structure to maintain the status of each queue.
59 */
60struct runq {
61	struct	rqbits rq_status;
62	struct	rqhead rq_queues[RQ_NQS];
63};
64
65void	runq_add(struct runq *, struct thread *, int);
66void	runq_add_pri(struct runq *, struct thread *, u_char, int);
67int	runq_check(struct runq *);
68struct	thread *runq_choose(struct runq *);
69struct	thread *runq_choose_from(struct runq *, u_char);
70struct	thread *runq_choose_fuzz(struct runq *, int);
71void	runq_init(struct runq *);
72void	runq_remove(struct runq *, struct thread *);
73void	runq_remove_idx(struct runq *, struct thread *, u_char *);
74
75#endif
76