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/**
* @file
*
* @brief Inlined Routines Associated with the CORE Mutexes
*
* This include file contains all of the inlined routines associated
* with the CORE mutexes.
*/
/*
* COPYRIGHT (c) 1989-2009.
* 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_COREMUTEX_H
# error "Never use <rtems/score/coremutex.inl> directly; include <rtems/score/coremutex.h> instead."
#endif
#ifndef _RTEMS_SCORE_COREMUTEX_INL
#define _RTEMS_SCORE_COREMUTEX_INL
#include <rtems/score/threaddispatch.h>
/**
* @addtogroup ScoreMutex
*/
/**@{**/
/**
* @brief Is mutex locked.
*
* This routine returns true if the mutex specified is locked and false
* otherwise.
*
* @param[in] the_mutex is the mutex to check.
*
* @retval true The mutex is locked.
* @retval false The mutex is not locked.
*/
RTEMS_INLINE_ROUTINE bool _CORE_mutex_Is_locked(
CORE_mutex_Control *the_mutex
)
{
return the_mutex->lock == CORE_MUTEX_LOCKED;
}
/**
* @brief Does core mutex use FIFO blocking.
*
* This routine returns true if the mutex's wait discipline is FIFO and false
* otherwise.
*
* @param[in] the_attribute is the attribute set of the mutex.
*
* @retval true The mutex is using FIFO blocking order.
* @retval false The mutex is not using FIFO blocking order.
*/
RTEMS_INLINE_ROUTINE bool _CORE_mutex_Is_fifo(
CORE_mutex_Attributes *the_attribute
)
{
return the_attribute->discipline == CORE_MUTEX_DISCIPLINES_FIFO;
}
/**
* @brief Doex core mutex use priority blocking.
*
* This routine returns true if the mutex's wait discipline is PRIORITY and
* false otherwise.
*
* @param[in] the_attribute is the attribute set of the mutex.
*
* @retval true The mutex is using priority blocking order.
* @retval false The mutex is not using priority blocking order.
*
*/
RTEMS_INLINE_ROUTINE bool _CORE_mutex_Is_priority(
CORE_mutex_Attributes *the_attribute
)
{
return the_attribute->discipline == CORE_MUTEX_DISCIPLINES_PRIORITY;
}
/**
* @brief Does mutex use priority inheritance.
*
* This routine returns true if the mutex's wait discipline is
* INHERIT_PRIORITY and false otherwise.
*
* @param[in] the_attribute is the attribute set of the mutex.
*
* @retval true The mutex is using priority inheritance.
* @retval false The mutex is not using priority inheritance.
*/
RTEMS_INLINE_ROUTINE bool _CORE_mutex_Is_inherit_priority(
CORE_mutex_Attributes *the_attribute
)
{
return the_attribute->discipline == CORE_MUTEX_DISCIPLINES_PRIORITY_INHERIT;
}
/**
* @brief Does mutex use priority ceiling.
*
* This routine returns true if the mutex's wait discipline is
* PRIORITY_CEILING and false otherwise.
*
* @param[in] the_attribute is the attribute set of the mutex.
*
* @retval true The mutex is using priority ceiling.
* @retval false The mutex is not using priority ceiling.
*/
RTEMS_INLINE_ROUTINE bool _CORE_mutex_Is_priority_ceiling(
CORE_mutex_Attributes *the_attribute
)
{
return the_attribute->discipline == CORE_MUTEX_DISCIPLINES_PRIORITY_CEILING;
}
/*
* Seize Mutex with Quick Success Path
*
* NOTE: There is no MACRO version of this routine. A body is in
* coremutexseize.c that is duplicated from the .inl by hand.
*
* NOTE: The Doxygen for this routine is in the .h file.
*/
RTEMS_INLINE_ROUTINE int _CORE_mutex_Seize_interrupt_trylock_body(
CORE_mutex_Control *the_mutex,
ISR_Level level
)
{
Thread_Control *executing;
/* disabled when you get here */
executing = _Thread_Executing;
executing->Wait.return_code = CORE_MUTEX_STATUS_SUCCESSFUL;
if ( !_CORE_mutex_Is_locked( the_mutex ) ) {
the_mutex->lock = CORE_MUTEX_LOCKED;
the_mutex->holder = executing;
the_mutex->holder_id = executing->Object.id;
the_mutex->nest_count = 1;
if ( _CORE_mutex_Is_inherit_priority( &the_mutex->Attributes ) ||
_CORE_mutex_Is_priority_ceiling( &the_mutex->Attributes ) ){
#ifdef __RTEMS_STRICT_ORDER_MUTEX__
_Chain_Prepend_unprotected( &executing->lock_mutex,
&the_mutex->queue.lock_queue );
the_mutex->queue.priority_before = executing->current_priority;
#endif
executing->resource_count++;
}
if ( !_CORE_mutex_Is_priority_ceiling( &the_mutex->Attributes ) ) {
_ISR_Enable( level );
return 0;
} /* else must be CORE_MUTEX_DISCIPLINES_PRIORITY_CEILING
*
* we possibly bump the priority of the current holder -- which
* happens to be _Thread_Executing.
*/
{
Priority_Control ceiling;
Priority_Control current;
ceiling = the_mutex->Attributes.priority_ceiling;
current = executing->current_priority;
if ( current == ceiling ) {
_ISR_Enable( level );
return 0;
}
if ( current > ceiling ) {
_Thread_Disable_dispatch();
_ISR_Enable( level );
_Thread_Change_priority(
the_mutex->holder,
the_mutex->Attributes.priority_ceiling,
false
);
_Thread_Enable_dispatch();
return 0;
}
/* if ( current < ceiling ) */ {
executing->Wait.return_code = CORE_MUTEX_STATUS_CEILING_VIOLATED;
the_mutex->lock = CORE_MUTEX_UNLOCKED;
the_mutex->nest_count = 0; /* undo locking above */
executing->resource_count--; /* undo locking above */
_ISR_Enable( level );
return 0;
}
}
return 0;
}
/*
* At this point, we know the mutex was not available. If this thread
* is the thread that has locked the mutex, let's see if we are allowed
* to nest access.
*/
if ( _Thread_Is_executing( the_mutex->holder ) ) {
switch ( the_mutex->Attributes.lock_nesting_behavior ) {
case CORE_MUTEX_NESTING_ACQUIRES:
the_mutex->nest_count++;
_ISR_Enable( level );
return 0;
#if defined(RTEMS_POSIX_API)
case CORE_MUTEX_NESTING_IS_ERROR:
executing->Wait.return_code = CORE_MUTEX_STATUS_NESTING_NOT_ALLOWED;
_ISR_Enable( level );
return 0;
#endif
case CORE_MUTEX_NESTING_BLOCKS:
break;
}
}
/*
* The mutex is not available and the caller must deal with the possibility
* of blocking.
*/
return 1;
}
/** @} */
#endif
/* end of include file */
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