1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef _LINUX_SCHED_PRIO_H |
3 | #define _LINUX_SCHED_PRIO_H |
4 | |
5 | #define MAX_NICE 19 |
6 | #define MIN_NICE -20 |
7 | #define NICE_WIDTH (MAX_NICE - MIN_NICE + 1) |
8 | |
9 | /* |
10 | * Priority of a process goes from 0..MAX_PRIO-1, valid RT |
11 | * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH |
12 | * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority |
13 | * values are inverted: lower p->prio value means higher priority. |
14 | */ |
15 | |
16 | #define MAX_RT_PRIO 100 |
17 | |
18 | #define MAX_PRIO (MAX_RT_PRIO + NICE_WIDTH) |
19 | #define DEFAULT_PRIO (MAX_RT_PRIO + NICE_WIDTH / 2) |
20 | |
21 | /* |
22 | * Convert user-nice values [ -20 ... 0 ... 19 ] |
23 | * to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ], |
24 | * and back. |
25 | */ |
26 | #define NICE_TO_PRIO(nice) ((nice) + DEFAULT_PRIO) |
27 | #define PRIO_TO_NICE(prio) ((prio) - DEFAULT_PRIO) |
28 | |
29 | /* |
30 | * Convert nice value [19,-20] to rlimit style value [1,40]. |
31 | */ |
32 | static inline long nice_to_rlimit(long nice) |
33 | { |
34 | return (MAX_NICE - nice + 1); |
35 | } |
36 | |
37 | /* |
38 | * Convert rlimit style value [1,40] to nice value [-20, 19]. |
39 | */ |
40 | static inline long rlimit_to_nice(long prio) |
41 | { |
42 | return (MAX_NICE - prio + 1); |
43 | } |
44 | |
45 | #endif /* _LINUX_SCHED_PRIO_H */ |
46 | |