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/**
* @file
*
* @brief Inlined Routines Associated with the SuperCore RWLock
*
* This include file contains all of the inlined routines associated
* with the SuperCore RWLock.
*/
/*
* COPYRIGHT (c) 1989-2008.
* 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.
*/
#ifndef _RTEMS_SCORE_CORERWLOCKIMPL_H
#define _RTEMS_SCORE_CORERWLOCKIMPL_H
#include <rtems/score/corerwlock.h>
#include <rtems/score/threadq.h>
#include <rtems/score/watchdog.h>
#ifdef __cplusplus
extern "C" {
#endif
/**
* @addtogroup ScoreRWLock
*/
/**@{**/
/**
* The following type defines the callout which the API provides
* to support global/multiprocessor operations on RWLocks.
*/
typedef void ( *CORE_RWLock_API_mp_support_callout )(
Thread_Control *,
Objects_Id
);
/**
* Core RWLock handler return statuses.
*/
typedef enum {
/** This status indicates that the operation completed successfully. */
CORE_RWLOCK_SUCCESSFUL,
/** This status indicates that the thread was blocked waiting for an */
CORE_RWLOCK_WAS_DELETED,
/** This status indicates that the rwlock was not immediately available. */
CORE_RWLOCK_UNAVAILABLE,
/** 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_RWLOCK_TIMEOUT
} CORE_RWLock_Status;
/** This is the last status value.
*/
#define CORE_RWLOCK_STATUS_LAST CORE_RWLOCK_TIMEOUT
/**
* This is used to denote that a thread is blocking waiting for
* read-only access to the RWLock.
*/
#define CORE_RWLOCK_THREAD_WAITING_FOR_READ 0
/**
* This is used to denote that a thread is blocking waiting for
* write-exclusive access to the RWLock.
*/
#define CORE_RWLOCK_THREAD_WAITING_FOR_WRITE 1
/**
* @brief Initialize a RWlock.
*
* This routine initializes the RWLock based on the parameters passed.
*
* @param[in] the_rwlock is the RWLock to initialize
* @param[in] the_rwlock_attributes define the behavior of this instance
*/
void _CORE_RWLock_Initialize(
CORE_RWLock_Control *the_rwlock,
CORE_RWLock_Attributes *the_rwlock_attributes
);
/**
* @brief Obtain RWLock for reading.
*
* This routine attempts to obtain the RWLock for read access.
*
* @param[in] the_rwlock is the RWLock 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_rwlock_mp_support is the routine to invoke if the
* thread unblocked is remote
*
* @note Status is returned via the thread control block.
*/
void _CORE_RWLock_Obtain_for_reading(
CORE_RWLock_Control *the_rwlock,
Thread_Control *executing,
Objects_Id id,
bool wait,
Watchdog_Interval timeout,
CORE_RWLock_API_mp_support_callout api_rwlock_mp_support
);
/**
* @brief Obtain RWLock for writing.
*
* This routine attempts to obtain the RWLock for write exclusive access.
*
* @param[in] the_rwlock is the RWLock 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_rwlock_mp_support is the routine to invoke if the
* thread unblocked is remote
*
* @note Status is returned via the thread control block.
*/
void _CORE_RWLock_Obtain_for_writing(
CORE_RWLock_Control *the_rwlock,
Thread_Control *executing,
Objects_Id id,
bool wait,
Watchdog_Interval timeout,
CORE_RWLock_API_mp_support_callout api_rwlock_mp_support
);
/**
* @brief Release the RWLock.
*
* This routine manually releases @a the_rwlock. All of the threads waiting
* for the RWLock will be readied.
*
* @param[in] the_rwlock is the RWLock to surrender
*
* @retval Status is returned to indicate successful or failure.
*/
CORE_RWLock_Status _CORE_RWLock_Release(
CORE_RWLock_Control *the_rwlock,
Thread_Control *executing
);
/**
* This routine assists in the deletion of a RWLock by flushing the
* associated wait queue.
*
* @param[in] _the_rwlock is the RWLock 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_RWLock_Flush( _the_rwlock, _remote_extract_callout, _status) \
_Thread_queue_Flush( \
&((_the_rwlock)->Wait_queue), \
(_remote_extract_callout), \
(_status) \
)
/**
* @brief RWLock specific thread queue timeout.
*
* This routine processes a thread which timeouts while waiting on
* an RWLock's thread queue. It is called by the watchdog handler.
*
* @param[in] id is the Id of thread to timeout
* @param[in] ignored is an unused pointer to a caller defined area
*/
void _CORE_RWLock_Timeout(
Objects_Id id,
void *ignored
);
/**
* This method is used to initialize core rwlock attributes.
*
* @param[in] the_attributes pointer to the attributes to initialize.
*/
RTEMS_INLINE_ROUTINE void _CORE_RWLock_Initialize_attributes(
CORE_RWLock_Attributes *the_attributes
)
{
the_attributes->XXX = 0;
}
/** @} */
#ifdef __cplusplus
}
#endif
#endif
/* end of include file */
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