/**
* @file rtems/score/scheduler.h
*
* @brief Constants and Structures Associated with the Scheduler
*
* This include file contains all the constants and structures associated
* with the scheduler.
*/
/*
* Copyright (C) 2010 Gedare Bloom.
* Copyright (C) 2011 On-Line Applications Research Corporation (OAR).
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.org/license/LICENSE.
*/
#ifndef _RTEMS_SCORE_SCHEDULER_H
#define _RTEMS_SCORE_SCHEDULER_H
#include <rtems/score/percpu.h>
#include <rtems/score/priority.h>
#include <rtems/score/thread.h>
#if defined(__RTEMS_HAVE_SYS_CPUSET_H__) && defined(RTEMS_SMP)
#include <sys/cpuset.h>
#endif
#ifdef __cplusplus
extern "C" {
#endif
/**
* @defgroup ScoreScheduler Scheduler Handler
*
* @ingroup Score
*
* This handler encapsulates functionality related to managing sets of threads
* that are ready for execution.
*/
/**@{*/
typedef struct Scheduler_Control Scheduler_Control;
typedef struct Scheduler_Node Scheduler_Node;
/**
* @brief The scheduler operations.
*/
typedef struct {
/** @see _Scheduler_Handler_initialization() */
void ( *initialize )( const Scheduler_Control * );
/** @see _Scheduler_Schedule() */
void ( *schedule )( const Scheduler_Control *, Thread_Control *);
/** @see _Scheduler_Yield() */
void ( *yield )( const Scheduler_Control *, Thread_Control *);
/** @see _Scheduler_Block() */
void ( *block )( const Scheduler_Control *, Thread_Control * );
/** @see _Scheduler_Unblock() */
void ( *unblock )( const Scheduler_Control *, Thread_Control * );
/** @see _Scheduler_Change_priority() */
void ( *change_priority )(
const Scheduler_Control *,
Thread_Control *,
Priority_Control,
bool
);
/** @see _Scheduler_Node_initialize() */
void ( *node_initialize )( const Scheduler_Control *, Thread_Control * );
/** @see _Scheduler_Node_destroy() */
void ( *node_destroy )( const Scheduler_Control *, Thread_Control * );
/** @see _Scheduler_Update_priority() */
void ( *update_priority )(
const Scheduler_Control *,
Thread_Control *,
Priority_Control
);
/** @see _Scheduler_Priority_compare() */
int ( *priority_compare )(
Priority_Control,
Priority_Control
);
/** @see _Scheduler_Release_job() */
void ( *release_job ) (
const Scheduler_Control *,
Thread_Control *,
uint32_t
);
/** @see _Scheduler_Tick() */
void ( *tick )( const Scheduler_Control *, Thread_Control * );
/** @see _Scheduler_Start_idle() */
void ( *start_idle )(
const Scheduler_Control *,
Thread_Control *,
Per_CPU_Control *
);
#if defined(__RTEMS_HAVE_SYS_CPUSET_H__) && defined(RTEMS_SMP)
/** @see _Scheduler_Get_affinity() */
bool ( *get_affinity )(
const Scheduler_Control *,
Thread_Control *,
size_t,
cpu_set_t *
);
/** @see _Scheduler_Set_affinity() */
bool ( *set_affinity )(
const Scheduler_Control *,
Thread_Control *,
size_t,
const cpu_set_t *
);
#endif
} Scheduler_Operations;
/**
* @brief Scheduler context.
*
* The scheduler context of a particular scheduler implementation must place
* this structure at the begin of its context structure.
*/
typedef struct Scheduler_Context {
#if defined(RTEMS_SMP)
/**
* @brief Count of processors owned by this scheduler instance.
*/
uint32_t processor_count;
#endif
} Scheduler_Context;
/**
* @brief Scheduler control.
*/
struct Scheduler_Control {
/**
* @brief Reference to a statically allocated scheduler context.
*/
Scheduler_Context *context;
/**
* @brief The scheduler operations.
*/
Scheduler_Operations Operations;
/**
* @brief The scheduler name.
*/
uint32_t name;
};
/**
* @brief Scheduler node for per-thread data.
*/
struct Scheduler_Node {
/* No fields yet */
};
/**
* @brief Registered schedulers.
*
* Application provided via <rtems/confdefs.h>.
*
* @see _Scheduler_Count.
*/
extern const Scheduler_Control _Scheduler_Table[];
/**
* @brief Count of registered schedulers.
*
* Application provided via <rtems/confdefs.h> on SMP configurations.
*
* It is very important that this is a compile-time constant on uni-processor
* configurations (in this case RTEMS_SMP is not defined) so that the compiler
* can optimize the some loops away
*
* @see _Scheduler_Table.
*/
#if defined(RTEMS_SMP)
extern const size_t _Scheduler_Count;
#else
#define _Scheduler_Count ( (size_t) 1 )
#endif
#if defined(RTEMS_SMP)
/**
* @brief The scheduler assignment default attributes.
*/
#define SCHEDULER_ASSIGN_DEFAULT UINT32_C(0x0)
/**
* @brief The presence of this processor is optional.
*/
#define SCHEDULER_ASSIGN_PROCESSOR_OPTIONAL SCHEDULER_ASSIGN_DEFAULT
/**
* @brief The presence of this processor is mandatory.
*/
#define SCHEDULER_ASSIGN_PROCESSOR_MANDATORY UINT32_C(0x1)
/**
* @brief Scheduler assignment.
*/
typedef struct {
/**
* @brief The scheduler for this processor.
*/
const Scheduler_Control *scheduler;
/**
* @brief The scheduler assignment attributes.
*
* Use @ref SCHEDULER_ASSIGN_DEFAULT to select default attributes.
*
* The presence of a processor can be
* - @ref SCHEDULER_ASSIGN_PROCESSOR_OPTIONAL, or
* - @ref SCHEDULER_ASSIGN_PROCESSOR_MANDATORY.
*/
uint32_t attributes;
} Scheduler_Assignment;
/**
* @brief The scheduler assignments.
*
* The length of this array must be equal to the maximum processors.
*
* Application provided via <rtems/confdefs.h>.
*
* @see _Scheduler_Table and rtems_configuration_get_maximum_processors().
*/
extern const Scheduler_Assignment _Scheduler_Assignments[];
#endif
/**
* @brief Does nothing.
*
* @param[in] scheduler Unused.
* @param[in] the_thread Unused.
*/
void _Scheduler_default_Schedule(
const Scheduler_Control *scheduler,
Thread_Control *the_thread
);
/**
* @brief Does nothing.
*
* @param[in] scheduler Unused.
* @param[in] the_thread Unused.
*/
void _Scheduler_default_Node_initialize(
const Scheduler_Control *scheduler,
Thread_Control *the_thread
);
/**
* @brief Does nothing.
*
* @param[in] scheduler Unused.
* @param[in] the_thread Unused.
*/
void _Scheduler_default_Node_destroy(
const Scheduler_Control *scheduler,
Thread_Control *the_thread
);
/**
* @brief Does nothing.
*
* @param[in] scheduler Unused.
* @param[in] the_thread Unused.
* @param[in] new_priority Unused.
*/
void _Scheduler_default_Update_priority(
const Scheduler_Control *scheduler,
Thread_Control *the_thread,
Priority_Control new_priority
);
/**
* @brief Does nothing.
*
* @param[in] scheduler Unused.
* @param[in] the_thread Unused.
* @param[in] deadline Unused.
*/
void _Scheduler_default_Release_job(
const Scheduler_Control *scheduler,
Thread_Control *the_thread,
uint32_t deadline
);
/**
* @brief Performs tick operations depending on the CPU budget algorithm for
* each executing thread.
*
* This routine is invoked as part of processing each clock tick.
*
* @param[in] scheduler The scheduler.
* @param[in] execution An executing thread.
*/
void _Scheduler_default_Tick(
const Scheduler_Control *scheduler,
Thread_Control *executing
);
/**
* @brief Starts an idle thread.
*
* @param[in] scheduler The scheduler.
* @param[in] the_thread An idle thread.
* @param[in] cpu This parameter is unused.
*/
void _Scheduler_default_Start_idle(
const Scheduler_Control *scheduler,
Thread_Control *the_thread,
Per_CPU_Control *cpu
);
#if defined(__RTEMS_HAVE_SYS_CPUSET_H__) && defined(RTEMS_SMP)
/**
* @brief Get affinity for the default scheduler.
*
* @param[in] thread The associated thread.
* @param[in] cpusetsize The size of the cpuset.
* @param[out] cpuset Affinity set containing all CPUs.
*
* @retval 0 Successfully got cpuset
* @retval -1 The cpusetsize is invalid for the system
*/
bool _Scheduler_default_Get_affinity(
const Scheduler_Control *scheduler,
Thread_Control *thread,
size_t cpusetsize,
cpu_set_t *cpuset
);
/**
* @brief Set affinity for the default scheduler.
*
* @param[in] thread The associated thread.
* @param[in] cpusetsize The size of the cpuset.
* @param[in] cpuset Affinity new affinity set.
*
* @retval 0 Successful
*
* This method always returns successful and does not save
* the cpuset.
*/
bool _Scheduler_default_Set_affinity(
const Scheduler_Control *scheduler,
Thread_Control *thread,
size_t cpusetsize,
const cpu_set_t *cpuset
);
#endif
/**
* @brief Indicates if thread priority queues are broken with the configured
* scheduler or not.
*
* See also PR2174: Memory corruption with EDF scheduler and thread priority
* queues.
*/
extern const bool _Scheduler_FIXME_thread_priority_queues_are_broken;
/**@}*/
#ifdef __cplusplus
}
#endif
#endif
/* end of include file */
