include/linux/sched/prio.h

   1 #ifndef _SCHED_PRIO_H
   2 #define _SCHED_PRIO_H
   3
   4 /*
   5  * Priority of a process goes from 0..MAX_PRIO-1, valid RT
   6  * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
   7  * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
   8  * values are inverted: lower p->prio value means higher priority.
   9  *
  10  * The MAX_USER_RT_PRIO value allows the actual maximum
  11  * RT priority to be separate from the value exported to
  12  * user-space.  This allows kernel threads to set their
  13  * priority to a value higher than any user task. Note:
  14  * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
  15  */
  16
  17 #define MAX_USER_RT_PRIO        100
  18 #define MAX_RT_PRIO             MAX_USER_RT_PRIO
  19
  20 #define MAX_PRIO                (MAX_RT_PRIO + 40)
  21 #define DEFAULT_PRIO            (MAX_RT_PRIO + 20)
  22
  23 /*
  24  * Convert user-nice values [ -20 ... 0 ... 19 ]
  25  * to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ],
  26  * and back.
  27  */
  28 #define NICE_TO_PRIO(nice)      (MAX_RT_PRIO + (nice) + 20)
  29 #define PRIO_TO_NICE(prio)      ((prio) - MAX_RT_PRIO - 20)
  30
  31 /*
  32  * 'User priority' is the nice value converted to something we
  33  * can work with better when scaling various scheduler parameters,
  34  * it's a [ 0 ... 39 ] range.
  35  */
  36 #define USER_PRIO(p)            ((p)-MAX_RT_PRIO)
  37 #define TASK_USER_PRIO(p)       USER_PRIO((p)->static_prio)
  38 #define MAX_USER_PRIO           (USER_PRIO(MAX_PRIO))
  39
  40 #endif /* _SCHED_PRIO_H */