blob: 10fbb8031930045d4dc04879c4fccf4bf372ac86 [file] [log] [blame]
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
#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;
__s32 sched_nice;
__u32 sched_priority;
__u64 sched_runtime;
__u64 sched_deadline;
__u64 sched_period;