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-rw-r--r--include/uapi/linux/sched/types.h74
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diff --git a/include/uapi/linux/sched/types.h b/include/uapi/linux/sched/types.h
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+#ifndef _UAPI_LINUX_SCHED_TYPES_H
+#define _UAPI_LINUX_SCHED_TYPES_H
+
+#include <linux/types.h>
+
+struct sched_param {
+ int sched_priority;
+};
+
+#define SCHED_ATTR_SIZE_VER0 48 /* sizeof first published struct */
+
+/*
+ * Extended scheduling parameters data structure.
+ *
+ * This is needed because the original struct sched_param can not be
+ * altered without introducing ABI issues with legacy applications
+ * (e.g., in sched_getparam()).
+ *
+ * However, the possibility of specifying more than just a priority for
+ * the tasks may be useful for a wide variety of application fields, e.g.,
+ * multimedia, streaming, automation and control, and many others.
+ *
+ * This variant (sched_attr) is meant at describing a so-called
+ * sporadic time-constrained task. In such model a task is specified by:
+ * - the activation period or minimum instance inter-arrival time;
+ * - the maximum (or average, depending on the actual scheduling
+ * discipline) computation time of all instances, a.k.a. runtime;
+ * - the deadline (relative to the actual activation time) of each
+ * instance.
+ * Very briefly, a periodic (sporadic) task asks for the execution of
+ * some specific computation --which is typically called an instance--
+ * (at most) every period. Moreover, each instance typically lasts no more
+ * than the runtime and must be completed by time instant t equal to
+ * the instance activation time + the deadline.
+ *
+ * This is reflected by the actual fields of the sched_attr structure:
+ *
+ * @size size of the structure, for fwd/bwd compat.
+ *
+ * @sched_policy task's scheduling policy
+ * @sched_flags for customizing the scheduler behaviour
+ * @sched_nice task's nice value (SCHED_NORMAL/BATCH)
+ * @sched_priority task's static priority (SCHED_FIFO/RR)
+ * @sched_deadline representative of the task's deadline
+ * @sched_runtime representative of the task's runtime
+ * @sched_period representative of the task's period
+ *
+ * Given this task model, there are a multiplicity of scheduling algorithms
+ * and policies, that can be used to ensure all the tasks will make their
+ * timing constraints.
+ *
+ * As of now, the SCHED_DEADLINE policy (sched_dl scheduling class) is the
+ * only user of this new interface. More information about the algorithm
+ * available in the scheduling class file or in Documentation/.
+ */
+struct sched_attr {
+ u32 size;
+
+ u32 sched_policy;
+ u64 sched_flags;
+
+ /* SCHED_NORMAL, SCHED_BATCH */
+ s32 sched_nice;
+
+ /* SCHED_FIFO, SCHED_RR */
+ u32 sched_priority;
+
+ /* SCHED_DEADLINE */
+ u64 sched_runtime;
+ u64 sched_deadline;
+ u64 sched_period;
+};
+
+#endif /* _UAPI_LINUX_SCHED_TYPES_H */