cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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types.h (4574B)

      1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
      2#ifndef _UAPI_LINUX_SCHED_TYPES_H
      3#define _UAPI_LINUX_SCHED_TYPES_H
      4
      5#include <linux/types.h>
      6
      7struct sched_param {
      8	int sched_priority;
      9};
     10
     11#define SCHED_ATTR_SIZE_VER0	48	/* sizeof first published struct */
     12#define SCHED_ATTR_SIZE_VER1	56	/* add: util_{min,max} */
     13
     14/*
     15 * Extended scheduling parameters data structure.
     16 *
     17 * This is needed because the original struct sched_param can not be
     18 * altered without introducing ABI issues with legacy applications
     19 * (e.g., in sched_getparam()).
     20 *
     21 * However, the possibility of specifying more than just a priority for
     22 * the tasks may be useful for a wide variety of application fields, e.g.,
     23 * multimedia, streaming, automation and control, and many others.
     24 *
     25 * This variant (sched_attr) allows to define additional attributes to
     26 * improve the scheduler knowledge about task requirements.
     27 *
     28 * Scheduling Class Attributes
     29 * ===========================
     30 *
     31 * A subset of sched_attr attributes specifies the
     32 * scheduling policy and relative POSIX attributes:
     33 *
     34 *  @size		size of the structure, for fwd/bwd compat.
     35 *
     36 *  @sched_policy	task's scheduling policy
     37 *  @sched_nice		task's nice value      (SCHED_NORMAL/BATCH)
     38 *  @sched_priority	task's static priority (SCHED_FIFO/RR)
     39 *
     40 * Certain more advanced scheduling features can be controlled by a
     41 * predefined set of flags via the attribute:
     42 *
     43 *  @sched_flags	for customizing the scheduler behaviour
     44 *
     45 * Sporadic Time-Constrained Task Attributes
     46 * =========================================
     47 *
     48 * A subset of sched_attr attributes allows to describe a so-called
     49 * sporadic time-constrained task.
     50 *
     51 * In such a model a task is specified by:
     52 *  - the activation period or minimum instance inter-arrival time;
     53 *  - the maximum (or average, depending on the actual scheduling
     54 *    discipline) computation time of all instances, a.k.a. runtime;
     55 *  - the deadline (relative to the actual activation time) of each
     56 *    instance.
     57 * Very briefly, a periodic (sporadic) task asks for the execution of
     58 * some specific computation --which is typically called an instance--
     59 * (at most) every period. Moreover, each instance typically lasts no more
     60 * than the runtime and must be completed by time instant t equal to
     61 * the instance activation time + the deadline.
     62 *
     63 * This is reflected by the following fields of the sched_attr structure:
     64 *
     65 *  @sched_deadline	representative of the task's deadline
     66 *  @sched_runtime	representative of the task's runtime
     67 *  @sched_period	representative of the task's period
     68 *
     69 * Given this task model, there are a multiplicity of scheduling algorithms
     70 * and policies, that can be used to ensure all the tasks will make their
     71 * timing constraints.
     72 *
     73 * As of now, the SCHED_DEADLINE policy (sched_dl scheduling class) is the
     74 * only user of this new interface. More information about the algorithm
     75 * available in the scheduling class file or in Documentation/.
     76 *
     77 * Task Utilization Attributes
     78 * ===========================
     79 *
     80 * A subset of sched_attr attributes allows to specify the utilization
     81 * expected for a task. These attributes allow to inform the scheduler about
     82 * the utilization boundaries within which it should schedule the task. These
     83 * boundaries are valuable hints to support scheduler decisions on both task
     84 * placement and frequency selection.
     85 *
     86 *  @sched_util_min	represents the minimum utilization
     87 *  @sched_util_max	represents the maximum utilization
     88 *
     89 * Utilization is a value in the range [0..SCHED_CAPACITY_SCALE]. It
     90 * represents the percentage of CPU time used by a task when running at the
     91 * maximum frequency on the highest capacity CPU of the system. For example, a
     92 * 20% utilization task is a task running for 2ms every 10ms at maximum
     93 * frequency.
     94 *
     95 * A task with a min utilization value bigger than 0 is more likely scheduled
     96 * on a CPU with a capacity big enough to fit the specified value.
     97 * A task with a max utilization value smaller than 1024 is more likely
     98 * scheduled on a CPU with no more capacity than the specified value.
     99 *
    100 * A task utilization boundary can be reset by setting the attribute to -1.
    101 */
    102struct sched_attr {
    103	__u32 size;
    104
    105	__u32 sched_policy;
    106	__u64 sched_flags;
    107
    108	/* SCHED_NORMAL, SCHED_BATCH */
    109	__s32 sched_nice;
    110
    111	/* SCHED_FIFO, SCHED_RR */
    112	__u32 sched_priority;
    113
    114	/* SCHED_DEADLINE */
    115	__u64 sched_runtime;
    116	__u64 sched_deadline;
    117	__u64 sched_period;
    118
    119	/* Utilization hints */
    120	__u32 sched_util_min;
    121	__u32 sched_util_max;
    122
    123};
    124
    125#endif /* _UAPI_LINUX_SCHED_TYPES_H */