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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /include/linux/sched/prio.h
Initial import
Diffstat (limited to 'include/linux/sched/prio.h')
-rw-r--r--include/linux/sched/prio.h72
1 files changed, 72 insertions, 0 deletions
diff --git a/include/linux/sched/prio.h b/include/linux/sched/prio.h
new file mode 100644
index 000000000..7d5d0b861
--- /dev/null
+++ b/include/linux/sched/prio.h
@@ -0,0 +1,72 @@
+#ifndef _SCHED_PRIO_H
+#define _SCHED_PRIO_H
+
+#define MAX_NICE 19
+#define MIN_NICE -20
+#define NICE_WIDTH (MAX_NICE - MIN_NICE + 1)
+
+/*
+ * Priority of a process goes from 0..MAX_PRIO-1, valid RT
+ * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
+ * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
+ * values are inverted: lower p->prio value means higher priority.
+ *
+ * The MAX_USER_RT_PRIO value allows the actual maximum
+ * RT priority to be separate from the value exported to
+ * user-space. This allows kernel threads to set their
+ * priority to a value higher than any user task. Note:
+ * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
+ */
+
+#define MAX_USER_RT_PRIO 100
+
+#ifdef CONFIG_SCHED_BFS
+/* Note different MAX_RT_PRIO */
+#define MAX_RT_PRIO (MAX_USER_RT_PRIO + 1)
+
+#define ISO_PRIO (MAX_RT_PRIO)
+#define NORMAL_PRIO (MAX_RT_PRIO + 1)
+#define IDLE_PRIO (MAX_RT_PRIO + 2)
+#define PRIO_LIMIT ((IDLE_PRIO) + 1)
+#else /* CONFIG_SCHED_BFS */
+#define MAX_RT_PRIO MAX_USER_RT_PRIO
+
+#endif /* CONFIG_SCHED_BFS */
+
+#define MAX_PRIO (MAX_RT_PRIO + NICE_WIDTH)
+#define DEFAULT_PRIO (MAX_RT_PRIO + NICE_WIDTH / 2)
+
+/*
+ * Convert user-nice values [ -20 ... 0 ... 19 ]
+ * to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ],
+ * and back.
+ */
+#define NICE_TO_PRIO(nice) ((nice) + DEFAULT_PRIO)
+#define PRIO_TO_NICE(prio) ((prio) - DEFAULT_PRIO)
+
+/*
+ * 'User priority' is the nice value converted to something we
+ * can work with better when scaling various scheduler parameters,
+ * it's a [ 0 ... 39 ] range.
+ */
+#define USER_PRIO(p) ((p)-MAX_RT_PRIO)
+#define TASK_USER_PRIO(p) USER_PRIO((p)->static_prio)
+#define MAX_USER_PRIO (USER_PRIO(MAX_PRIO))
+
+/*
+ * Convert nice value [19,-20] to rlimit style value [1,40].
+ */
+static inline long nice_to_rlimit(long nice)
+{
+ return (MAX_NICE - nice + 1);
+}
+
+/*
+ * Convert rlimit style value [1,40] to nice value [-20, 19].
+ */
+static inline long rlimit_to_nice(long prio)
+{
+ return (MAX_NICE - prio + 1);
+}
+
+#endif /* _SCHED_PRIO_H */