include/linux/sched/rt.h

   1 #ifndef _SCHED_RT_H
   2 #define _SCHED_RT_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 static inline int rt_prio(int prio)
  24 {
  25         if (unlikely(prio < MAX_RT_PRIO))
  26                 return 1;
  27         return 0;
  28 }
  29
  30 static inline int rt_task(struct task_struct *p)
  31 {
  32         return rt_prio(p->prio);
  33 }
  34
  35 #ifdef CONFIG_RT_MUTEXES
  36 extern int rt_mutex_getprio(struct task_struct *p);
  37 extern void rt_mutex_setprio(struct task_struct *p, int prio);
  38 extern struct task_struct *rt_mutex_get_top_task(struct task_struct *task);
  39 extern void rt_mutex_adjust_pi(struct task_struct *p);
  40 static inline bool tsk_is_pi_blocked(struct task_struct *tsk)
  41 {
  42         return tsk->pi_blocked_on != NULL;
  43 }
  44 #else
  45 static inline int rt_mutex_getprio(struct task_struct *p)
  46 {
  47         return p->normal_prio;
  48 }
  49 static inline struct task_struct *rt_mutex_get_top_task(struct task_struct *task)
  50 {
  51         return NULL;
  52 }
  53 # define rt_mutex_adjust_pi(p)          do { } while (0)
  54 static inline bool tsk_is_pi_blocked(struct task_struct *tsk)
  55 {
  56         return false;
  57 }
  58 #endif
  59
  60 extern void normalize_rt_tasks(void);
  61
  62
  63 /*
  64  * default timeslice is 100 msecs (used only for SCHED_RR tasks).
  65  * Timeslices get refilled after they expire.
  66  */
  67 #define RR_TIMESLICE            (100 * HZ / 1000)
  68
  69 #endif /* _SCHED_RT_H */