prio.h 1.1 KB

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