1/*-
2 * SPDX-License-Identifier: BSD-4-Clause
3 *
4 * Copyright (c) 1994, Henrik Vestergaard Draboel
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 * 3. All advertising materials mentioning features or use of this software
16 *    must display the following acknowledgement:
17 *	This product includes software developed by Henrik Vestergaard Draboel.
18 * 4. The name of the author may not be used to endorse or promote products
19 *    derived from this software without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 * $FreeBSD$
34 */
35
36#ifndef _SYS_PRIORITY_H_
37#define _SYS_PRIORITY_H_
38
39/*
40 * Process priority specifications.
41 */
42
43/*
44 * Priority classes.
45 */
46
47#define	PRI_ITHD		1	/* Interrupt thread. */
48#define	PRI_REALTIME		2	/* Real time process. */
49#define	PRI_TIMESHARE		3	/* Time sharing process. */
50#define	PRI_IDLE		4	/* Idle process. */
51
52/*
53 * PRI_FIFO is POSIX.1B SCHED_FIFO.
54 */
55
56#define	PRI_FIFO_BIT		8
57#define	PRI_FIFO		(PRI_FIFO_BIT | PRI_REALTIME)
58
59#define	PRI_BASE(P)		((P) & ~PRI_FIFO_BIT)
60#define	PRI_IS_REALTIME(P)	(PRI_BASE(P) == PRI_REALTIME)
61#define	PRI_NEED_RR(P)		((P) != PRI_FIFO)
62
63/*
64 * Priorities.  Note that with 64 run queues, differences less than 4 are
65 * insignificant.
66 */
67
68/*
69 * Priorities range from 0 to 255, but differences of less then 4 (RQ_PPQ)
70 * are insignificant.  Ranges are as follows:
71 *
72 * Interrupt threads:		0 - 47
73 * Realtime user threads:	48 - 79
74 * Top half kernel threads:	80 - 119
75 * Time sharing user threads:	120 - 223
76 * Idle user threads:		224 - 255
77 *
78 * XXX If/When the specific interrupt thread and top half thread ranges
79 * disappear, a larger range can be used for user processes.
80 */
81
82#define	PRI_MIN			(0)		/* Highest priority. */
83#define	PRI_MAX			(255)		/* Lowest priority. */
84
85#define	PRI_MIN_ITHD		(PRI_MIN)
86#define	PRI_MAX_ITHD		(PRI_MIN_REALTIME - 1)
87
88#define	PI_REALTIME		(PRI_MIN_ITHD + 0)
89#define	PI_AV			(PRI_MIN_ITHD + 4)
90#define	PI_NET			(PRI_MIN_ITHD + 8)
91#define	PI_DISK			(PRI_MIN_ITHD + 12)
92#define	PI_TTY			(PRI_MIN_ITHD + 16)
93#define	PI_DULL			(PRI_MIN_ITHD + 20)
94#define	PI_SOFT			(PRI_MIN_ITHD + 24)
95#define	PI_SWI(x)		(PI_SOFT + (x) * RQ_PPQ)
96
97#define	PRI_MIN_REALTIME	(48)
98#define	PRI_MAX_REALTIME	(PRI_MIN_KERN - 1)
99
100#define	PRI_MIN_KERN		(80)
101#define	PRI_MAX_KERN		(PRI_MIN_TIMESHARE - 1)
102
103#define	PSWP			(PRI_MIN_KERN + 0)
104#define	PVM			(PRI_MIN_KERN + 4)
105#define	PINOD			(PRI_MIN_KERN + 8)
106#define	PRIBIO			(PRI_MIN_KERN + 12)
107#define	PVFS			(PRI_MIN_KERN + 16)
108#define	PZERO			(PRI_MIN_KERN + 20)
109#define	PSOCK			(PRI_MIN_KERN + 24)
110#define	PWAIT			(PRI_MIN_KERN + 28)
111#define	PLOCK			(PRI_MIN_KERN + 32)
112#define	PPAUSE			(PRI_MIN_KERN + 36)
113
114#define	PRI_MIN_TIMESHARE	(120)
115#define	PRI_MAX_TIMESHARE	(PRI_MIN_IDLE - 1)
116
117#define	PUSER			(PRI_MIN_TIMESHARE)
118
119#define	PRI_MIN_IDLE		(224)
120#define	PRI_MAX_IDLE		(PRI_MAX)
121
122#ifdef _KERNEL
123/* Other arguments for kern_yield(9). */
124#define	PRI_USER	-2	/* Change to current user priority. */
125#define	PRI_UNCHANGED	-1	/* Do not change priority. */
126#endif
127
128struct priority {
129	u_char	pri_class;	/* Scheduling class. */
130	u_char	pri_level;	/* Normal priority level. */
131	u_char	pri_native;	/* Priority before propagation. */
132	u_char	pri_user;	/* User priority based on p_cpu and p_nice. */
133};
134
135#endif	/* !_SYS_PRIORITY_H_ */
136