1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2001 Jake Burkholder <jake@FreeBSD.org>
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#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