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Diffstat (limited to 'cpukit/rtems/src/ratemon.c')
| -rw-r--r-- | cpukit/rtems/src/ratemon.c | 401 |
1 files changed, 401 insertions, 0 deletions
diff --git a/cpukit/rtems/src/ratemon.c b/cpukit/rtems/src/ratemon.c new file mode 100644 index 0000000000..3c0733a3ab --- /dev/null +++ b/cpukit/rtems/src/ratemon.c @@ -0,0 +1,401 @@ +/* + * Rate Monotonic Manager + * + * + * COPYRIGHT (c) 1989, 1990, 1991, 1992, 1993, 1994. + * On-Line Applications Research Corporation (OAR). + * All rights assigned to U.S. Government, 1994. + * + * This material may be reproduced by or for the U.S. Government pursuant + * to the copyright license under the clause at DFARS 252.227-7013. This + * notice must appear in all copies of this file and its derivatives. + * + * $Id$ + */ + +#include <rtems/system.h> +#include <rtems/isr.h> +#include <rtems/object.h> +#include <rtems/ratemon.h> +#include <rtems/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, + FALSE, + maximum_periods, + sizeof( Rate_monotonic_Control ) + ); +} + +/*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( + Objects_Name name, + Objects_Id *id +) +{ + Rate_monotonic_Control *the_period; + + if ( !_Objects_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( + Objects_Name name, + Objects_Id *id +) +{ + return _Objects_Name_to_id( + &_Rate_monotonic_Information, + name, + RTEMS_SEARCH_LOCAL_NODE, + id + ); +} + +/*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_ERROR: + return( RTEMS_INVALID_ID ); + case OBJECTS_REMOTE: /* should never return this */ + return( RTEMS_INTERNAL_ERROR ); + 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_ERROR: + return( RTEMS_INVALID_ID ); + case OBJECTS_REMOTE: /* should never return this */ + return( RTEMS_INTERNAL_ERROR ); + 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_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; + + the_period = _Rate_monotonic_Get( id, &location ); + switch ( location ) { + case OBJECTS_ERROR: + return( RTEMS_INVALID_ID ); + case OBJECTS_REMOTE: /* should never return this */ + return( RTEMS_INTERNAL_ERROR ); + 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 ); + } + + switch ( the_period->state ) { + case RATE_MONOTONIC_INACTIVE: + the_period->state = RATE_MONOTONIC_ACTIVE; + _Watchdog_Initialize( + &the_period->Timer, + _Rate_monotonic_Timeout, + id, + NULL + ); + _Watchdog_Insert_ticks( + &the_period->Timer, length, WATCHDOG_ACTIVATE_NOW ); + _Thread_Enable_dispatch(); + return( RTEMS_SUCCESSFUL ); + + case RATE_MONOTONIC_ACTIVE: +/* following is and could be a critical section problem */ + _Thread_Executing->Wait.id = the_period->Object.id; + if ( _Rate_monotonic_Set_state( the_period ) ) { + _Thread_Enable_dispatch(); + return( RTEMS_SUCCESSFUL ); + } + /* has expired -- fall into next case */ + case RATE_MONOTONIC_EXPIRED: + the_period->state = RATE_MONOTONIC_ACTIVE; + _Watchdog_Insert_ticks( + &the_period->Timer, length, WATCHDOG_ACTIVATE_NOW ); + _Thread_Enable_dispatch(); + return( RTEMS_TIMEOUT ); + } + } + + return( RTEMS_INTERNAL_ERROR ); /* unreached - only to remove warnings */ +} + +/*PAGE + * + * _Rate_monotonic_Set_state + * + * This kernel routine sets the STATES_WAITING_FOR_PERIOD state in + * the running thread's tcb if the specified period has not expired. + * The ready chain is adjusted if necessary. + * + * Input parameters: + * the_period - pointer to period control block + * + * Output parameters: + * TRUE - if blocked successfully for period + * FALSE - if period has expired + * + * INTERRUPT LATENCY: + * delete node + * priority map + * select heir + */ + +boolean _Rate_monotonic_Set_state( +Rate_monotonic_Control *the_period +) +{ + Thread_Control *executing; + Chain_Control *ready; + ISR_Level level; + States_Control old_state; + + executing = _Thread_Executing; + ready = executing->ready; + _ISR_Disable( level ); + + old_state = executing->current_state; + + if ( _Rate_monotonic_Is_expired( the_period ) ) { + _ISR_Enable( level ); + return( FALSE ); + } + + executing->current_state = + _States_Set( STATES_WAITING_FOR_PERIOD, old_state ); + + if ( _States_Is_ready( old_state ) ) { + if ( _Chain_Has_only_one_node( ready ) ) { + _Chain_Initialize_empty( ready ); + _Priority_Remove_from_bit_map( &executing->Priority_map ); + _ISR_Flash( level ); + } else { + _Chain_Extract_unprotected( &executing->Object.Node ); + _ISR_Flash( level ); + } + + if ( _Thread_Is_heir( executing ) ) + _Thread_Calculate_heir(); + + _Context_Switch_necessary = TRUE; + } + + _ISR_Enable( level ); + return( TRUE ); +} + +/*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_ERROR: + case OBJECTS_REMOTE: /* impossible */ + 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 ); + _Watchdog_Reset( &the_period->Timer ); + } + else + the_period->state = RATE_MONOTONIC_EXPIRED; + _Thread_Unnest_dispatch(); + break; + } +} + |