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Reimplemented _Core_MUTEX_Seize to return with interrupts disabled

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if the mutex is successfully obtained.
This commit is contained in:
Joel Sherrill
2000-07-06 19:32:00 +00:00
parent 8d5b438b9e
commit 21e2b2b9be
4 changed files with 238 additions and 14 deletions
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36
c/src/exec/score/include/rtems/score/coremutex.h
View File

@@ -149,15 +149,41 @@ void _CORE_mutex_Initialize(
* If a unit is available or if the wait flag is FALSE, then the routine
* returns. Otherwise, the calling task is blocked until a unit becomes
* available.
*
* NOTE: For performance reasons, this routine is implemented as
* a macro that uses two support routines.
*/
void _CORE_mutex_Seize(
RTEMS_INLINE_ROUTINE int _CORE_mutex_Seize_interrupt_trylock(
CORE_mutex_Control *the_mutex,
ISR_Level *level_p
);
void _CORE_mutex_Seize_interrupt_blocking(
CORE_mutex_Control *the_mutex,
Objects_Id id,
boolean wait,
Watchdog_Interval timeout
);
#define _CORE_mutex_Seize( \
_the_mutex, _id, _wait, _timeout, _level ) \
do { \
if ( _CORE_mutex_Seize_interrupt_trylock( _the_mutex, &_level ) ) { \
if ( !_wait ) { \
_ISR_Enable( _level ); \
_Thread_Executing->Wait.return_code = \
CORE_MUTEX_STATUS_UNSATISFIED_NOWAIT; \
} else { \
_Thread_queue_Enter_critical_section( &(_the_mutex)->Wait_queue ); \
_Thread_Executing->Wait.queue = &(_the_mutex)->Wait_queue; \
_Thread_Executing->Wait.id = _id; \
_Thread_Disable_dispatch(); \
_ISR_Enable( _level ); \
_CORE_mutex_Seize_interrupt_blocking( _the_mutex, _id, _timeout ); \
} \
} \
} while (0)
/*
* _CORE_mutex_Surrender
*
@@ -189,10 +215,6 @@ void _CORE_mutex_Flush(
unsigned32 status
);
#ifndef __RTEMS_APPLICATION__
#include <rtems/score/coremutex.inl>
#endif
#ifdef __cplusplus
}
#endif

90
c/src/exec/score/inline/rtems/score/coremutex.inl
View File

@@ -101,5 +101,95 @@ RTEMS_INLINE_ROUTINE boolean _CORE_mutex_Is_priority_ceiling(
return the_attribute->discipline == CORE_MUTEX_DISCIPLINES_PRIORITY_CEILING;
}
/*PAGE
*
* _CORE_mutex_Seize_interrupt_trylock
*
* DESCRIPTION:
*
* This routine returns 0 if "trylock" can resolve whether or not the
* mutex is immediately obtained or there was an error attempting to
* get it. It returns 1 to indicate that the caller cannot obtain
* the mutex and will have to block to do so.
*
* NOTE: There is no MACRO version of this routine.
*/
RTEMS_INLINE_ROUTINE int _CORE_mutex_Seize_interrupt_trylock(
CORE_mutex_Control *the_mutex,
ISR_Level *level_p
)
{
Thread_Control *executing;
ISR_Level level = *level_p;
/* 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;
executing->resource_count++;
if ( the_mutex->Attributes.discipline !=
CORE_MUTEX_DISCIPLINES_PRIORITY_CEILING ) {
_ISR_Enable( level );
return 0;
}
/* else must be CORE_MUTEX_DISCIPLINES_PRIORITY_CEILING */
{
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->nest_count = 0; /* undo locking above */
executing->resource_count--; /* undo locking above */
_ISR_Enable( level );
return 0;
}
}
return 0;
}
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;
case CORE_MUTEX_NESTING_IS_ERROR:
executing->Wait.return_code = CORE_MUTEX_STATUS_NESTING_NOT_ALLOWED;
_ISR_Enable( level );
return 0;
case CORE_MUTEX_NESTING_BLOCKS:
break;
}
}
return 1;
}
#endif
#endif
/* end of include file */

36
cpukit/score/include/rtems/score/coremutex.h
View File

@@ -149,15 +149,41 @@ void _CORE_mutex_Initialize(
* If a unit is available or if the wait flag is FALSE, then the routine
* returns. Otherwise, the calling task is blocked until a unit becomes
* available.
*
* NOTE: For performance reasons, this routine is implemented as
* a macro that uses two support routines.
*/
void _CORE_mutex_Seize(
RTEMS_INLINE_ROUTINE int _CORE_mutex_Seize_interrupt_trylock(
CORE_mutex_Control *the_mutex,
ISR_Level *level_p
);
void _CORE_mutex_Seize_interrupt_blocking(
CORE_mutex_Control *the_mutex,
Objects_Id id,
boolean wait,
Watchdog_Interval timeout
);
#define _CORE_mutex_Seize( \
_the_mutex, _id, _wait, _timeout, _level ) \
do { \
if ( _CORE_mutex_Seize_interrupt_trylock( _the_mutex, &_level ) ) { \
if ( !_wait ) { \
_ISR_Enable( _level ); \
_Thread_Executing->Wait.return_code = \
CORE_MUTEX_STATUS_UNSATISFIED_NOWAIT; \
} else { \
_Thread_queue_Enter_critical_section( &(_the_mutex)->Wait_queue ); \
_Thread_Executing->Wait.queue = &(_the_mutex)->Wait_queue; \
_Thread_Executing->Wait.id = _id; \
_Thread_Disable_dispatch(); \
_ISR_Enable( _level ); \
_CORE_mutex_Seize_interrupt_blocking( _the_mutex, _id, _timeout ); \
} \
} \
} while (0)
/*
* _CORE_mutex_Surrender
*
@@ -189,10 +215,6 @@ void _CORE_mutex_Flush(
unsigned32 status
);
#ifndef __RTEMS_APPLICATION__
#include <rtems/score/coremutex.inl>
#endif
#ifdef __cplusplus
}
#endif

90
cpukit/score/inline/rtems/score/coremutex.inl
View File

@@ -101,5 +101,95 @@ RTEMS_INLINE_ROUTINE boolean _CORE_mutex_Is_priority_ceiling(
return the_attribute->discipline == CORE_MUTEX_DISCIPLINES_PRIORITY_CEILING;
}
/*PAGE
*
* _CORE_mutex_Seize_interrupt_trylock
*
* DESCRIPTION:
*
* This routine returns 0 if "trylock" can resolve whether or not the
* mutex is immediately obtained or there was an error attempting to
* get it. It returns 1 to indicate that the caller cannot obtain
* the mutex and will have to block to do so.
*
* NOTE: There is no MACRO version of this routine.
*/
RTEMS_INLINE_ROUTINE int _CORE_mutex_Seize_interrupt_trylock(
CORE_mutex_Control *the_mutex,
ISR_Level *level_p
)
{
Thread_Control *executing;
ISR_Level level = *level_p;
/* 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;
executing->resource_count++;
if ( the_mutex->Attributes.discipline !=
CORE_MUTEX_DISCIPLINES_PRIORITY_CEILING ) {
_ISR_Enable( level );
return 0;
}
/* else must be CORE_MUTEX_DISCIPLINES_PRIORITY_CEILING */
{
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->nest_count = 0; /* undo locking above */
executing->resource_count--; /* undo locking above */
_ISR_Enable( level );
return 0;
}
}
return 0;
}
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;
case CORE_MUTEX_NESTING_IS_ERROR:
executing->Wait.return_code = CORE_MUTEX_STATUS_NESTING_NOT_ALLOWED;
_ISR_Enable( level );
return 0;
case CORE_MUTEX_NESTING_BLOCKS:
break;
}
}
return 1;
}
#endif
#endif
/* end of include file */