/*
* Rate Monotonic Manager
*
*
* COPYRIGHT (c) 1989-1998.
* On-Line Applications Research Corporation (OAR).
* Copyright assigned to U.S. Government, 1994.
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.OARcorp.com/rtems/license.html.
*
* $Id$
*/
#include <rtems/system.h>
#include <rtems/rtems/status.h>
#include <rtems/rtems/support.h>
#include <rtems/score/isr.h>
#include <rtems/score/object.h>
#include <rtems/rtems/ratemon.h>
#include <rtems/score/thread.h>
/*PAGE
*
* _Rate_monotonic_Manager_initialization
*
* This routine initializes all Rate Monotonic Manager related
* data structures.
*
* Input parameters:
* maximum_periods - number of periods timers to initialize
*
* Output parameters: NONE
*
* NOTE: The Rate Monotonic Manager is built on top of the Watchdog
* Handler.
*/
void _Rate_monotonic_Manager_initialization(
unsigned32 maximum_periods
)
{
_Objects_Initialize_information(
&_Rate_monotonic_Information,
OBJECTS_RTEMS_PERIODS,
FALSE,
maximum_periods,
sizeof( Rate_monotonic_Control ),
FALSE,
RTEMS_MAXIMUM_NAME_LENGTH,
FALSE
);
}
/*PAGE
*
* rtems_rate_monotonic_create
*
* This directive creates a rate monotonic timer and performs
* some initialization.
*
* Input parameters:
* name - name of period
* id - pointer to rate monotonic id
*
* Output parameters:
* id - rate monotonic id
* RTEMS_SUCCESSFUL - if successful
* error code - if unsuccessful
*/
rtems_status_code rtems_rate_monotonic_create(
rtems_name name,
Objects_Id *id
)
{
Rate_monotonic_Control *the_period;
if ( !rtems_is_name_valid( name ) )
return RTEMS_INVALID_NAME;
_Thread_Disable_dispatch(); /* to prevent deletion */
the_period = _Rate_monotonic_Allocate();
if ( !the_period ) {
_Thread_Enable_dispatch();
return RTEMS_TOO_MANY;
}
the_period->owner = _Thread_Executing;
the_period->state = RATE_MONOTONIC_INACTIVE;
_Objects_Open( &_Rate_monotonic_Information, &the_period->Object, &name );
*id = the_period->Object.id;
_Thread_Enable_dispatch();
return RTEMS_SUCCESSFUL;
}
/*PAGE
*
* rtems_rate_monotonic_ident
*
* This directive returns the system ID associated with
* the rate monotonic period name.
*
* Input parameters:
* name - user defined period name
* id - pointer to period id
*
* Output parameters:
* *id - region id
* RTEMS_SUCCESSFUL - if successful
* error code - if unsuccessful
*/
rtems_status_code rtems_rate_monotonic_ident(
rtems_name name,
Objects_Id *id
)
{
Objects_Name_to_id_errors status;
status = _Objects_Name_to_id(
&_Rate_monotonic_Information,
&name,
OBJECTS_SEARCH_LOCAL_NODE,
id
);
return _Status_Object_name_errors_to_status[ status ];
}
/*PAGE
*
* rtems_rate_monotonic_cancel
*
* This directive allows a thread to cancel a rate monotonic timer.
*
* Input parameters:
* id - rate monotonic id
*
* Output parameters:
* RTEMS_SUCCESSFUL - if successful and caller is not the owning thread
* error code - if unsuccessful
*/
rtems_status_code rtems_rate_monotonic_cancel(
Objects_Id id
)
{
Rate_monotonic_Control *the_period;
Objects_Locations location;
the_period = _Rate_monotonic_Get( id, &location );
switch ( location ) {
case OBJECTS_REMOTE:
return RTEMS_INTERNAL_ERROR; /* should never return this */
case OBJECTS_ERROR:
return RTEMS_INVALID_ID;
case OBJECTS_LOCAL:
if ( !_Thread_Is_executing( the_period->owner ) ) {
_Thread_Enable_dispatch();
return RTEMS_NOT_OWNER_OF_RESOURCE;
}
(void) _Watchdog_Remove( &the_period->Timer );
the_period->state = RATE_MONOTONIC_INACTIVE;
_Thread_Enable_dispatch();
return RTEMS_SUCCESSFUL;
}
return RTEMS_INTERNAL_ERROR; /* unreached - only to remove warnings */
}
/*PAGE
*
* rtems_rate_monotonic_delete
*
* This directive allows a thread to delete a rate monotonic timer.
*
* Input parameters:
* id - rate monotonic id
*
* Output parameters:
* RTEMS_SUCCESSFUL - if successful
* error code - if unsuccessful
*/
rtems_status_code rtems_rate_monotonic_delete(
Objects_Id id
)
{
Rate_monotonic_Control *the_period;
Objects_Locations location;
the_period = _Rate_monotonic_Get( id, &location );
switch ( location ) {
case OBJECTS_REMOTE: /* should never return this */
return RTEMS_INTERNAL_ERROR;
case OBJECTS_ERROR:
return RTEMS_INVALID_ID;
case OBJECTS_LOCAL:
_Objects_Close( &_Rate_monotonic_Information, &the_period->Object );
(void) _Watchdog_Remove( &the_period->Timer );
the_period->state = RATE_MONOTONIC_INACTIVE;
_Rate_monotonic_Free( the_period );
_Thread_Enable_dispatch();
return RTEMS_SUCCESSFUL;
}
return RTEMS_INTERNAL_ERROR; /* unreached - only to remove warnings */
}
/*PAGE
*
* rtems_rate_monotonic_get_status
*
* This directive allows a thread to obtain status information on a
* period.
*
* Input parameters:
* id - rate monotonic id
* status - pointer to status control block
*
* Output parameters:
* RTEMS_SUCCESSFUL - if successful
* error code - if unsuccessful
*
*/
rtems_status_code rtems_rate_monotonic_get_status(
Objects_Id id,
rtems_rate_monotonic_period_status *status
)
{
Objects_Locations location;
Rate_monotonic_Control *the_period;
if ( status == NULL )
return RTEMS_INVALID_ADDRESS;
the_period = _Rate_monotonic_Get( id, &location );
switch ( location ) {
case OBJECTS_REMOTE: /* should never return this */
return RTEMS_INTERNAL_ERROR;
case OBJECTS_ERROR:
return RTEMS_INVALID_ID;
case OBJECTS_LOCAL:
status->state = the_period->state;
if ( status->state == RATE_MONOTONIC_INACTIVE ) {
status->ticks_since_last_period = 0;
status->ticks_executed_since_last_period = 0;
} else {
status->ticks_since_last_period =
_Watchdog_Ticks_since_boot - the_period->time_at_period;
status->ticks_executed_since_last_period =
the_period->owner->ticks_executed -
the_period->owner_ticks_executed_at_period;
}
_Thread_Enable_dispatch();
return RTEMS_SUCCESSFUL;
}
return RTEMS_INTERNAL_ERROR; /* unreached - only to remove warnings */
}
/*PAGE
*
* rtems_rate_monotonic_period
*
* This directive allows a thread to manipulate a rate monotonic timer.
*
* Input parameters:
* id - rate monotonic id
* length - length of period (in ticks)
*
* Output parameters:
* RTEMS_SUCCESSFUL - if successful
* error code - if unsuccessful
*/
rtems_status_code rtems_rate_monotonic_period(
Objects_Id id,
rtems_interval length
)
{
Rate_monotonic_Control *the_period;
Objects_Locations location;
rtems_status_code return_value;
rtems_rate_monotonic_period_states local_state;
ISR_Level level;
the_period = _Rate_monotonic_Get( id, &location );
switch ( location ) {
case OBJECTS_REMOTE: /* should never return this */
return RTEMS_INTERNAL_ERROR;
case OBJECTS_ERROR:
return RTEMS_INVALID_ID;
case OBJECTS_LOCAL:
if ( !_Thread_Is_executing( the_period->owner ) ) {
_Thread_Enable_dispatch();
return RTEMS_NOT_OWNER_OF_RESOURCE;
}
if ( length == RTEMS_PERIOD_STATUS ) {
switch ( the_period->state ) {
case RATE_MONOTONIC_INACTIVE:
return_value = RTEMS_NOT_DEFINED;
break;
case RATE_MONOTONIC_ACTIVE:
return_value = RTEMS_SUCCESSFUL;
break;
case RATE_MONOTONIC_EXPIRED:
return_value = RTEMS_TIMEOUT;
break;
default: /* unreached -- only to remove warnings */
return_value = RTEMS_INTERNAL_ERROR;
break;
}
_Thread_Enable_dispatch();
return( return_value );
}
_ISR_Disable( level );
switch ( the_period->state ) {
case RATE_MONOTONIC_INACTIVE:
_ISR_Enable( level );
the_period->state = RATE_MONOTONIC_ACTIVE;
_Watchdog_Initialize(
&the_period->Timer,
_Rate_monotonic_Timeout,
id,
NULL
);
the_period->owner_ticks_executed_at_period =
_Thread_Executing->ticks_executed;
the_period->time_at_period = _Watchdog_Ticks_since_boot;
_Watchdog_Insert_ticks( &the_period->Timer, length );
_Thread_Enable_dispatch();
return RTEMS_SUCCESSFUL;
case RATE_MONOTONIC_ACTIVE:
/*
* This tells the _Rate_monotonic_Timeout that this task is
* in the process of blocking on the period.
*/
the_period->state = RATE_MONOTONIC_OWNER_IS_BLOCKING;
_ISR_Enable( level );
_Thread_Executing->Wait.id = the_period->Object.id;
_Thread_Set_state( _Thread_Executing, STATES_WAITING_FOR_PERIOD );
/*
* Did the watchdog timer expire while we were actually blocking
* on it?
*/
_ISR_Disable( level );
local_state = the_period->state;
the_period->state = RATE_MONOTONIC_ACTIVE;
_ISR_Enable( level );
/*
* If it did, then we want to unblock ourself and continue as
* if nothing happen. The period was reset in the timeout routine.
*/
if ( local_state == RATE_MONOTONIC_EXPIRED_WHILE_BLOCKING )
_Thread_Clear_state( _Thread_Executing, STATES_WAITING_FOR_PERIOD );
_Thread_Enable_dispatch();
return RTEMS_SUCCESSFUL;
break;
case RATE_MONOTONIC_EXPIRED:
_ISR_Enable( level );
the_period->state = RATE_MONOTONIC_ACTIVE;
the_period->owner_ticks_executed_at_period =
_Thread_Executing->ticks_executed;
the_period->time_at_period = _Watchdog_Ticks_since_boot;
_Watchdog_Insert_ticks( &the_period->Timer, length );
_Thread_Enable_dispatch();
return RTEMS_TIMEOUT;
case RATE_MONOTONIC_OWNER_IS_BLOCKING:
case RATE_MONOTONIC_EXPIRED_WHILE_BLOCKING:
/*
* These should never happen.
*/
break;
}
}
return RTEMS_INTERNAL_ERROR; /* unreached - only to remove warnings */
}
/*PAGE
*
* _Rate_monotonic_Timeout
*
* This routine processes a period ending. If the owning thread
* is waiting for the period, that thread is unblocked and the
* period reinitiated. Otherwise, the period is expired.
* This routine is called by the watchdog handler.
*
* Input parameters:
* id - period id
*
* Output parameters: NONE
*/
void _Rate_monotonic_Timeout(
Objects_Id id,
void *ignored
)
{
Rate_monotonic_Control *the_period;
Objects_Locations location;
Thread_Control *the_thread;
the_period = _Rate_monotonic_Get( id, &location );
switch ( location ) {
case OBJECTS_REMOTE: /* impossible */
case OBJECTS_ERROR:
break;
case OBJECTS_LOCAL:
the_thread = the_period->owner;
if ( _States_Is_waiting_for_period( the_thread->current_state ) &&
the_thread->Wait.id == the_period->Object.id ) {
_Thread_Unblock( the_thread );
the_period->owner_ticks_executed_at_period =
the_thread->ticks_executed;
the_period->time_at_period = _Watchdog_Ticks_since_boot;
_Watchdog_Reset( &the_period->Timer );
} else if ( the_period->state == RATE_MONOTONIC_OWNER_IS_BLOCKING ) {
the_period->state = RATE_MONOTONIC_EXPIRED_WHILE_BLOCKING;
the_period->owner_ticks_executed_at_period =
the_thread->ticks_executed;
the_period->time_at_period = _Watchdog_Ticks_since_boot;
_Watchdog_Reset( &the_period->Timer );
} else
the_period->state = RATE_MONOTONIC_EXPIRED;
_Thread_Unnest_dispatch();
break;
}
}