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Diffstat (limited to 'cpukit/include/rtems/rtems/tasks.h')
| -rw-r--r-- | cpukit/include/rtems/rtems/tasks.h | 716 |
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diff --git a/cpukit/include/rtems/rtems/tasks.h b/cpukit/include/rtems/rtems/tasks.h new file mode 100644 index 0000000000..585f4c449c --- /dev/null +++ b/cpukit/include/rtems/rtems/tasks.h @@ -0,0 +1,716 @@ +/** + * @file rtems/rtems/tasks.h + * + * @defgroup ClassicTasks Tasks + * + * @ingroup ClassicRTEMS + * @brief RTEMS Tasks + * + * This include file contains all constants and structures associated + * with RTEMS tasks. This manager provides a comprehensive set of directives + * to create, delete, and administer tasks. + * + * Directives provided are: + * + * - create a task + * - get an ID of a task + * - start a task + * - restart a task + * - delete a task + * - suspend a task + * - resume a task + * - set a task's priority + * - change the current task's mode + * - wake up after interval + * - wake up when specified + */ + +/* + * COPYRIGHT (c) 1989-2014. + * 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_RTEMS_TASKS_H +#define _RTEMS_RTEMS_TASKS_H + +#include <rtems/score/object.h> +#include <rtems/score/scheduler.h> +#include <rtems/score/thread.h> +#include <rtems/rtems/types.h> +#include <rtems/rtems/event.h> +#include <rtems/rtems/asr.h> +#include <rtems/rtems/attr.h> +#include <rtems/rtems/status.h> + +#ifdef __cplusplus +extern "C" { +#endif + +/** + * @defgroup ClassicTasks Tasks + * + * @ingroup ClassicRTEMS + * + * This encapsulates the functionality of the Classic API Task Manager. + * This functionality includes task services such as creation, deletion, + * delays, suspend/resume, and manipulation of execution mode and priority. + */ +/**@{*/ + +/** + * Constant to be used as the ID of current task + */ +#define RTEMS_SELF OBJECTS_ID_OF_SELF + +/** + * This constant is passed to the rtems_task_wake_after directive as the + * interval when a task wishes to yield the CPU. + */ +#define RTEMS_YIELD_PROCESSOR WATCHDOG_NO_TIMEOUT + +/** + * Define the type for an RTEMS API task priority. + */ +typedef uint32_t rtems_task_priority; + +/** + * This is the constant used with the rtems_task_set_priority + * directive to indicate that the caller wants to obtain its + * current priority rather than set it as the name of the + * directive indicates. + */ +#define RTEMS_NO_PRIORITY RTEMS_CURRENT_PRIORITY + +/** + * This constant is the least valid value for a Classic API + * task priority. + */ +#define RTEMS_MINIMUM_PRIORITY (PRIORITY_MINIMUM + 1) + +/** + * This constant is the maximum valid value for a Classic API + * task priority. + * + * @note This is actually the priority of the IDLE thread so + * using this priority will result in having a task + * which never executes. This could be useful if you + * want to ensure that a task does not executes during + * certain operations such as a system mode change. + */ +#define RTEMS_MAXIMUM_PRIORITY ((rtems_task_priority) PRIORITY_MAXIMUM) + +/** + * The following constant is passed to rtems_task_set_priority when the + * caller wants to obtain the current priority. + */ +#define RTEMS_CURRENT_PRIORITY PRIORITY_MINIMUM + +/** + * External API name for Thread_Control + */ +typedef Thread_Control rtems_tcb; + +/** + * The following defines the "return type" of an RTEMS task. + */ +typedef void rtems_task; + +/** + * The following defines the argument to an RTEMS task. + */ +typedef Thread_Entry_numeric_type rtems_task_argument; + +/** + * The following defines the type for the entry point of an RTEMS task. + */ +typedef rtems_task ( *rtems_task_entry )( + rtems_task_argument + ); + +/** + * The following records define the Initialization Tasks Table. + * Each entry contains the information required by RTEMS to + * create and start a user task automatically at executive + * initialization time. + */ +typedef struct { + /** This is the Initialization Task's name. */ + rtems_name name; + /** This is the Initialization Task's stack size. */ + size_t stack_size; + /** This is the Initialization Task's priority. */ + rtems_task_priority initial_priority; + /** This is the Initialization Task's attributes. */ + rtems_attribute attribute_set; + /** This is the Initialization Task's entry point. */ + rtems_task_entry entry_point; + /** This is the Initialization Task's initial mode. */ + rtems_mode mode_set; + /** This is the Initialization Task's argument. */ + rtems_task_argument argument; +} rtems_initialization_tasks_table; + +/** + * @brief RTEMS Task Create + * + * This routine implements the rtems_task_create directive. The task + * will have the name name. The attribute_set can be used to indicate + * that the task will be globally accessible or utilize floating point. + * The task's stack will be stack_size bytes. The task will begin + * execution with initial_priority and initial_modes. It returns the + * id of the created task in ID. + * + * @param[in] name is the user defined thread name + * @param[in] initial_priority is the thread priority + * @param[in] stack_size is the stack size in bytes + * @param[in] initial_modes is the initial thread mode + * @param[in] attribute_set is the thread attributes + * @param[in] id is the pointer to thread id + * + * @retval RTEMS_SUCCESSFUL if successful or error code if unsuccessful + * and *id thread id filled in + */ +rtems_status_code rtems_task_create( + rtems_name name, + rtems_task_priority initial_priority, + size_t stack_size, + rtems_mode initial_modes, + rtems_attribute attribute_set, + rtems_id *id +); + +/** + * @brief RTEMS Task Name to Id + * + * This routine implements the rtems_task_ident directive. + * This directive returns the task ID associated with name. + * If more than one task is named name, then the task to + * which the ID belongs is arbitrary. node indicates the + * extent of the search for the ID of the task named name. + * The search can be limited to a particular node or allowed to + * encompass all nodes. + * + * @param[in] name is the user defined thread name + * @param[in] node is(are) the node(s) to be searched + * @param[in] id is the pointer to thread id + * + * @retval This method returns RTEMS_SUCCESSFUL if there was not an + * error. Otherwise, a status code is returned indicating the + * source of the error. If successful, the id will + * be filled in with the thread id. + */ +rtems_status_code rtems_task_ident( + rtems_name name, + uint32_t node, + rtems_id *id +); + +/** + * @brief RTEMS Delete Task + * + * This routine implements the rtems_task_delete directive. The + * task indicated by ID is deleted. The executive halts execution + * of the thread and frees the thread control block. + * + * @param[in] id is the thread id + * + * @retval This method returns RTEMS_SUCCESSFUL if there was not an + * error and id is not the requesting thread. Status code is + * returned indicating the source of the error. Nothing + * is returned if id is the requesting thread (always succeeds). + */ +rtems_status_code rtems_task_delete( + rtems_id id +); + +/** + * @brief RTEMS Task Mode + * + * This routine implements the rtems_task_mode directive. The current + * values of the modes indicated by mask of the calling task are changed + * to that indicated in mode_set. The former mode of the task is + * returned in mode_set. + * + * @param[in] mode_set is the new mode + * @param[in] mask is the mask + * @param[in] previous_mode_set is the address of previous mode set + * + * @retval RTEMS_SUCCESSFUL and previous_mode_set filled in with the + * previous mode set + */ +rtems_status_code rtems_task_mode( + rtems_mode mode_set, + rtems_mode mask, + rtems_mode *previous_mode_set +); + +/** + * @brief RTEMS Task Restart + * + * This routine implements the rtems_task_restart directive. The + * task associated with ID is restarted at its initial entry + * point with the new argument. + * + * @param[in] id is the thread id + * @param[in] arg is the thread argument + * + * @retval RTEMS_SUCCESSFUL if successful or error code if unsuccessful + */ +rtems_status_code rtems_task_restart( + rtems_id id, + uint32_t arg +); + +/** + * @brief RTEMS Suspend Task + * + * This routine implements the rtems_task_suspend directive. The + * SUSPENDED state is set for task associated with ID. Note that the + * suspended state can be in addition to other waiting states. + * + * @param[in] id is the thread id + * + * @retval This method returns RTEMS_SUCCESSFUL if there was not an + * error. Otherwise, a status code is returned indicating the + * source of the error. + */ +rtems_status_code rtems_task_suspend( + rtems_id id +); + +/** + * @brief RTEMS Resume Task + * + * This routine implements the rtems_task_resume Directive. The + * SUSPENDED state is cleared for task associated with ID. + * + * @param[in] id is the thread id + * + * @retval This method returns RTEMS_SUCCESSFUL if there was not an + * error. Otherwise, a status code is returned indicating the + * source of the error. + */ +rtems_status_code rtems_task_resume( + rtems_id id +); + +/** + * @brief RTEMS Set Task Priority + * + * This routine implements the rtems_task_set_priority directive. The + * current priority of the task associated with ID is set to + * new_priority. The former priority of that task is returned + * in old_priority. + * + * @param[in] id is the thread to extract + * @param[in] new_priority is the thread to extract + * @param[in] old_priority is the thread to extract + * + * @retval RTEMS_SUCCESSFUL if successful or error code if unsuccessful and + * and *old_priority filled in with the previous previous priority + */ +rtems_status_code rtems_task_set_priority( + rtems_id id, + rtems_task_priority new_priority, + rtems_task_priority *old_priority +); + +/** + * @brief Gets the current priority of the specified task with respect to the + * specified scheduler instance. + * + * The current priority reflects temporary priority adjustments due to locking + * protocols, the rate-monotonic period objects on some schedulers and other + * mechanisms. + * + * @param[in] task_id Identifier of the task. Use @ref RTEMS_SELF to select + * the executing task. + * @param[in] scheduler_id Identifier of the scheduler instance. + * @param[out] priority Returns the current priority of the specified task with + * respect to the specified scheduler instance. + * + * @retval RTEMS_SUCCESSFUL Successful operation. + * @retval RTEMS_ILLEGAL_ON_REMOTE_OBJECT Directive is illegal on remote tasks. + * @retval RTEMS_INVALID_ADDRESS The priority parameter is @c NULL. + * @retval RTEMS_INVALID_ID Invalid task or scheduler identifier. + * @retval RTEMS_NOT_DEFINED The task has no priority within the specified + * scheduler instance. This error is only possible on SMP configurations. + * + * @see rtems_scheduler_ident(). + */ +rtems_status_code rtems_task_get_priority( + rtems_id task_id, + rtems_id scheduler_id, + rtems_task_priority *priority +); + +/** + * @brief RTEMS Start Task + * + * RTEMS Task Manager + * + * This routine implements the rtems_task_start directive. The + * starting execution point of the task associated with ID is + * set to entry_point with the initial argument. + */ +rtems_status_code rtems_task_start( + rtems_id id, + rtems_task_entry entry_point, + rtems_task_argument argument +); + +/** + * @brief RTEMS Task Wake When + * + * This routine implements the rtems_task_wake_when directive. The + * calling task is blocked until the current time of day is + * equal to that indicated by time_buffer. + * + * @param[in] time_buffer is the pointer to the time and date structure + * + * @retval RTEMS_SUCCESSFUL if successful or error code if unsuccessful + */ +rtems_status_code rtems_task_wake_when( + rtems_time_of_day *time_buffer +); + +/** + * @brief RTEMS Task Wake After + * + * This routine implements the rtems_task_wake_after directive. The + * calling task is blocked until the indicated number of clock + * ticks have occurred. + * + * @param[in] ticks is the number of ticks to wait + * @retval RTEMS_SUCCESSFUL + */ +rtems_status_code rtems_task_wake_after( + rtems_interval ticks +); + +/** + * @brief rtems_task_is_suspended + * + * This directive returns a status indicating whether or not + * the specified task is suspended. + */ +rtems_status_code rtems_task_is_suspended( + rtems_id id +); + +/** + * @brief Gets the processor affinity set of a task. + * + * @param[in] id Identifier of the task. Use @ref RTEMS_SELF to select the + * executing task. + * @param[in] cpusetsize Size of the specified affinity set buffer in + * bytes. This value must be positive. + * @param[out] cpuset The current processor affinity set of the task. A set + * bit in the affinity set means that the task can execute on this processor + * and a cleared bit means the opposite. + * + * @retval RTEMS_SUCCESSFUL Successful operation. + * @retval RTEMS_INVALID_ADDRESS The @a cpuset parameter is @c NULL. + * @retval RTEMS_INVALID_ID Invalid task identifier. + * @retval RTEMS_INVALID_NUMBER The affinity set buffer is too small for the + * current processor affinity set of the task. + */ +rtems_status_code rtems_task_get_affinity( + rtems_id id, + size_t cpusetsize, + cpu_set_t *cpuset +); + +/** + * @brief Sets the processor affinity set of a task. + * + * This function will not change the scheduler of the task. The intersection + * of the processor affinity set and the set of processors owned by the + * scheduler of the task must be non-empty. It is not an error if the + * processor affinity set contains processors that are not part of the set of + * processors owned by the scheduler instance of the task. A task will simply + * not run under normal circumstances on these processors since the scheduler + * ignores them. Some locking protocols may temporarily use processors that + * are not included in the processor affinity set of the task. It is also not + * an error if the processor affinity set contains processors that are not part + * of the system. + * + * @param[in] id Identifier of the task. Use @ref RTEMS_SELF to select the + * executing task. + * @param[in] cpusetsize Size of the specified affinity set buffer in + * bytes. This value must be positive. + * @param[in] cpuset The new processor affinity set for the task. A set bit in + * the affinity set means that the task can execute on this processor and a + * cleared bit means the opposite. + * + * @retval RTEMS_SUCCESSFUL Successful operation. + * @retval RTEMS_INVALID_ADDRESS The @a cpuset parameter is @c NULL. + * @retval RTEMS_INVALID_ID Invalid task identifier. + * @retval RTEMS_INVALID_NUMBER Invalid processor affinity set. + */ +rtems_status_code rtems_task_set_affinity( + rtems_id id, + size_t cpusetsize, + const cpu_set_t *cpuset +); + +/** + * @brief Gets the scheduler of a task. + * + * @param[in] task_id Identifier of the task. Use @ref RTEMS_SELF to select + * the executing task. + * @param[out] scheduler_id Identifier of the scheduler instance. + * + * @retval RTEMS_SUCCESSFUL Successful operation. + * @retval RTEMS_INVALID_ADDRESS The @a scheduler_id parameter is @c NULL. + * @retval RTEMS_INVALID_ID Invalid task identifier. + */ +rtems_status_code rtems_task_get_scheduler( + rtems_id task_id, + rtems_id *scheduler_id +); + +/** + * @brief Sets the scheduler instance of a task. + * + * Initially, the scheduler instance of a task is set to the scheduler instance + * of the task that created it. This directive allows to move a task from its + * current scheduler instance to another specified by the scheduler identifier. + * + * @param[in] task_id Identifier of the task. Use @ref RTEMS_SELF to select + * the executing task. + * @param[in] scheduler_id Identifier of the scheduler instance. + * @param[in] priority The task priority with respect to the new scheduler + * instance. The real and initial priority of the task is set to this value. + * The initial priority is used by rtems_task_restart() for example. + * + * @retval RTEMS_SUCCESSFUL Successful operation. + * @retval RTEMS_ILLEGAL_ON_REMOTE_OBJECT Directive is illegal on remote tasks. + * @retval RTEMS_INVALID_ID Invalid task or scheduler identifier. + * @retval RTEMS_INVALID_PRIORITY Invalid priority. + * @retval RTEMS_RESOURCE_IN_USE The task owns resources which deny a scheduler + * change. + * + * @see rtems_scheduler_ident(). + */ +rtems_status_code rtems_task_set_scheduler( + rtems_id task_id, + rtems_id scheduler_id, + rtems_task_priority priority +); + +/** + * @brief RTEMS Get Self Task Id + * + * This directive returns the ID of the currently executing task. + */ +rtems_id rtems_task_self(void); + +/** + * @brief Task visitor. + * + * @param[in] tcb The task control block. + * @param[in] arg The visitor argument. + * + * @retval true Stop the iteration. + * @retval false Otherwise. + * + * @see rtems_task_iterate(). + */ +typedef bool ( *rtems_task_visitor )( rtems_tcb *tcb, void *arg ); + +/** + * @brief Iterates over all tasks in the system. + * + * This operation covers all tasks of all APIs. + * + * Must be called from task context. This operation obtains and releases the + * objects allocator lock. The task visitor is called while owning the objects + * allocator lock. It is possible to perform blocking operations in the task + * visitor, however, take care that no deadlocks via the object allocator lock + * can occur. + * + * @param[in] visitor The task visitor. + * @param[in] arg The visitor argument. + */ +void rtems_task_iterate( + rtems_task_visitor visitor, + void *arg +); + +/** + * @brief Identifies a scheduler by its name. + * + * The scheduler name is determined by the scheduler configuration. + * + * @param[in] name The scheduler name. + * @param[out] id The scheduler identifier associated with the name. + * + * @retval RTEMS_SUCCESSFUL Successful operation. + * @retval RTEMS_INVALID_ADDRESS The @a id parameter is @c NULL. + * @retval RTEMS_INVALID_NAME Invalid scheduler name. + */ +rtems_status_code rtems_scheduler_ident( + rtems_name name, + rtems_id *id +); + +/** + * @brief Identifies a scheduler by a processor index. + * + * @param[in] cpu_index The processor index. + * @param[out] id The scheduler identifier associated with the processor index. + * + * @retval RTEMS_SUCCESSFUL Successful operation. + * @retval RTEMS_INVALID_ADDRESS The @a id parameter is @c NULL. + * @retval RTEMS_INVALID_NAME Invalid processor index. + * @retval RTEMS_INCORRECT_STATE The processor index is valid, however, this + * processor is not owned by a scheduler. + */ +rtems_status_code rtems_scheduler_ident_by_processor( + uint32_t cpu_index, + rtems_id *id +); + +/** + * @brief Identifies a scheduler by a processor set. + * + * The scheduler is selected according to the highest numbered online processor + * in the specified processor set. + * + * @param[in] cpusetsize Size of the specified processor set buffer in + * bytes. This value must be positive. + * @param[out] cpuset The processor set to identify the scheduler. + * @param[out] id The scheduler identifier associated with the processor set. + * + * @retval RTEMS_SUCCESSFUL Successful operation. + * @retval RTEMS_INVALID_ADDRESS The @a id parameter is @c NULL. + * @retval RTEMS_INVALID_SIZE Invalid processor set size. + * @retval RTEMS_INVALID_NAME The processor set contains no online processor. + * @retval RTEMS_INCORRECT_STATE The processor set is valid, however, the + * highest numbered online processor in the specified processor set is not + * owned by a scheduler. + */ +rtems_status_code rtems_scheduler_ident_by_processor_set( + size_t cpusetsize, + const cpu_set_t *cpuset, + rtems_id *id +); + +/** + * @brief Gets the set of processors owned by the specified scheduler instance. + * + * @param[in] scheduler_id Identifier of the scheduler instance. + * @param[in] cpusetsize Size of the specified processor set buffer in + * bytes. This value must be positive. + * @param[out] cpuset The processor set owned by the scheduler. A set bit in + * the processor set means that this processor is owned by the scheduler and a + * cleared bit means the opposite. + * + * @retval RTEMS_SUCCESSFUL Successful operation. + * @retval RTEMS_INVALID_ADDRESS The @a cpuset parameter is @c NULL. + * @retval RTEMS_INVALID_ID Invalid scheduler instance identifier. + * @retval RTEMS_INVALID_NUMBER The processor set buffer is too small for the + * set of processors owned by the scheduler. + */ +rtems_status_code rtems_scheduler_get_processor_set( + rtems_id scheduler_id, + size_t cpusetsize, + cpu_set_t *cpuset +); + +/** + * @brief Adds a processor to the set of processors owned by the specified + * scheduler instance. + * + * Must be called from task context. This operation obtains and releases the + * objects allocator lock. + * + * @param[in] scheduler_id Identifier of the scheduler instance. + * @param[in] cpu_index Index of the processor to add. + * + * @retval RTEMS_SUCCESSFUL Successful operation. + * @retval RTEMS_INVALID_ID Invalid scheduler instance identifier. + * @retval RTEMS_NOT_CONFIGURED The processor is not configured to be used by + * the application. + * @retval RTEMS_INCORRECT_STATE The processor is configured to be used by + * the application, however, it is not online. + * @retval RTEMS_RESOURCE_IN_USE The processor is already assigned to a + * scheduler instance. + */ +rtems_status_code rtems_scheduler_add_processor( + rtems_id scheduler_id, + uint32_t cpu_index +); + +/** + * @brief Removes a processor from set of processors owned by the specified + * scheduler instance. + * + * Must be called from task context. This operation obtains and releases the + * objects allocator lock. Removing a processor from a scheduler is a complex + * operation that involves all tasks of the system. + * + * @param[in] scheduler_id Identifier of the scheduler instance. + * @param[in] cpu_index Index of the processor to add. + * + * @retval RTEMS_SUCCESSFUL Successful operation. + * @retval RTEMS_INVALID_ID Invalid scheduler instance identifier. + * @retval RTEMS_INVALID_NUMBER The processor is not owned by the specified + * scheduler instance. + * @retval RTEMS_RESOURCE_IN_USE The set of processors owned by the specified + * scheduler instance would be empty after the processor removal and there + * exists a non-idle task that uses this scheduler instance as its home + * scheduler instance. + */ +rtems_status_code rtems_scheduler_remove_processor( + rtems_id scheduler_id, + uint32_t cpu_index +); + +/**@}*/ + +/** + * This is the API specific information required by each thread for + * the RTEMS API to function correctly. + * + */ +typedef struct { + /** This field contains the event control for this task. */ + Event_Control Event; + /** This field contains the system event control for this task. */ + Event_Control System_event; + /** This field contains the Classic API Signal information for this task. */ + ASR_Information Signal; + + /** + * @brief Signal post-switch action in case signals are pending. + */ + Thread_Action Signal_action; +} RTEMS_API_Control; + +/** + * @brief _RTEMS_tasks_Initialize_user_tasks_body + * + * This routine creates and starts all configured user + * initialization threads. + * + * Input parameters: NONE + * + * Output parameters: NONE + * + * RTEMS Task Manager + */ + +extern void _RTEMS_tasks_Initialize_user_tasks_body( void ); + +#ifdef __cplusplus +} +#endif + +#endif +/* end of include file */ |