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Diffstat (limited to 'cpukit/score/include/rtems/score/corebarrier.h')
-rw-r--r-- | cpukit/score/include/rtems/score/corebarrier.h | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/cpukit/score/include/rtems/score/corebarrier.h b/cpukit/score/include/rtems/score/corebarrier.h new file mode 100644 index 0000000000..05ec152487 --- /dev/null +++ b/cpukit/score/include/rtems/score/corebarrier.h @@ -0,0 +1,202 @@ +/** + * @file rtems/score/corebarrier.h + * + * This include file contains all the constants and structures associated + * with the Barrier Handler. + */ + +/* + * COPYRIGHT (c) 1989-2007. + * 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.com/license/LICENSE. + * + * $Id$ + */ + +#ifndef _RTEMS_SCORE_COREBARRIER_H +#define _RTEMS_SCORE_COREBARRIER_H + +/** + * @defgroup ScoreBarrier Barrier Handler + * + * This handler encapsulates functionality which provides the foundation + * Barrier services used in all of the APIs supported by RTEMS. + */ +/**@{*/ + +#ifdef __cplusplus +extern "C" { +#endif + +#include <rtems/score/thread.h> +#include <rtems/score/threadq.h> +#include <rtems/score/priority.h> +#include <rtems/score/watchdog.h> + +/** + * The following type defines the callout which the API provides + * to support global/multiprocessor operations on barriers. + */ +typedef void ( *CORE_barrier_API_mp_support_callout )( + Thread_Control *, + Objects_Id + ); + +/** + * Flavors of barriers. + */ +typedef enum { + /** This specifies that the barrier will automatically release when + * the user specified number of threads have arrived at the barrier. + */ + CORE_BARRIER_AUTOMATIC_RELEASE, + /** This specifies that the user will have to manually release the barrier + * in order to release the waiting threads. + */ + CORE_BARRIER_MANUAL_RELEASE +} CORE_barrier_Disciplines; + +/** + * Core Barrier handler return statuses. + */ +typedef enum { + /** This status indicates that the operation completed successfully. */ + CORE_BARRIER_STATUS_SUCCESSFUL, + /** This status indicates that the barrier is configured for automatic + * release and the caller tripped the automatic release. The caller + * thus did not block. + */ + CORE_BARRIER_STATUS_AUTOMATICALLY_RELEASED, + /** This status indicates that the thread was blocked waiting for an + * operation to complete and the barrier was deleted. + */ + CORE_BARRIER_WAS_DELETED, + /** This status indicates that the calling task was willing to block + * but the operation was unable to complete within the time allotted + * because the resource never became available. + */ + CORE_BARRIER_TIMEOUT +} CORE_barrier_Status; + +/** + * @brief Core Barrier Last Status + * + * This is the last status value. + */ +#define CORE_BARRIER_STATUS_LAST CORE_BARRIER_TIMEOUT + +/** + * The following defines the control block used to manage the + * attributes of each barrier. + */ +typedef struct { + /** This field indicates whether the barrier is automatic or manual. + */ + CORE_barrier_Disciplines discipline; + /** This element indicates the number of threads which must arrive at the + * barrier to trip the automatic release. + */ + uint32_t maximum_count; +} CORE_barrier_Attributes; + +/** + * The following defines the control block used to manage each + * barrier. + */ +typedef struct { + /** This field is the Waiting Queue used to manage the set of tasks + * which are blocked waiting for the barrier to be released. + */ + Thread_queue_Control Wait_queue; + /** This element is the set of attributes which define this instance's + * behavior. + */ + CORE_barrier_Attributes Attributes; + /** This element contains the current number of thread waiting for this + * barrier to be released. */ + uint32_t number_of_waiting_threads; +} CORE_barrier_Control; + +/** + * This routine initializes the barrier based on the parameters passed. + * + * @param[in] the_barrier is the barrier to initialize + * @param[in] the_barrier_attributes define the behavior of this instance + */ +void _CORE_barrier_Initialize( + CORE_barrier_Control *the_barrier, + CORE_barrier_Attributes *the_barrier_attributes +); + +/** + * This routine wait for the barrier to be released. If the barrier + * is set to automatic and this is the appropriate thread, then it returns + * immediately. Otherwise, the calling thread is blocked until the barrier + * is released. + * + * @param[in] the_barrier is the barrier to wait for + * @param[in] id is the id of the object being waited upon + * @param[in] wait is true if the calling thread is willing to wait + * @param[in] timeout is the number of ticks the calling thread is willing + * to wait if @a wait is true. + * @param[in] api_barrier_mp_support is the routine to invoke if the + * thread unblocked is remote + * + * @note Status is returned via the thread control block. + */ +void _CORE_barrier_Wait( + CORE_barrier_Control *the_barrier, + Objects_Id id, + bool wait, + Watchdog_Interval timeout, + CORE_barrier_API_mp_support_callout api_barrier_mp_support +); + +/** + * This routine manually releases the barrier. All of the threads waiting + * for the barrier will be readied. + * + * @param[in] the_barrier is the barrier to surrender + * @param[in] id is the id of the object for a remote unblock + * @param[in] api_barrier_mp_support is the routine to invoke if the + * thread unblocked is remote + * + * @return the number of unblocked threads + */ +uint32_t _CORE_barrier_Release( + CORE_barrier_Control *the_barrier, + Objects_Id id, + CORE_barrier_API_mp_support_callout api_barrier_mp_support +); + +/** + * This routine assists in the deletion of a barrier by flushing the + * associated wait queue. + * + * @param[in] _the_barrier is the barrier to flush + * @param[in] _remote_extract_callout is the routine to invoke if the + * thread unblocked is remote + * @param[in] _status is the status to be returned to the unblocked thread + */ +#define _CORE_barrier_Flush( _the_barrier, _remote_extract_callout, _status) \ + _Thread_queue_Flush( \ + &((_the_barrier)->Wait_queue), \ + (_remote_extract_callout), \ + (_status) \ + ) + +#ifndef __RTEMS_APPLICATION__ +#include <rtems/score/corebarrier.inl> +#endif + +#ifdef __cplusplus +} +#endif + +/**@}*/ + +#endif +/* end of include file */ |