source: rtems/cpukit/score/src/mpci.c @ 6c7caa1a

/**
 * @file
 *
 * @brief Multiprocessing Communications Interface (MPCI) Handler
 * @ingroup ScoreMPCI
 */

/*
 *  COPYRIGHT (c) 1989-2014.
 *  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.org/license/LICENSE.
 */

#if HAVE_CONFIG_H
#include "config.h"
#endif

#include <rtems/score/mpciimpl.h>
#include <rtems/score/coresemimpl.h>
#include <rtems/score/interr.h>
#include <rtems/score/stackimpl.h>
#include <rtems/score/sysstate.h>
#include <rtems/score/schedulerimpl.h>
#include <rtems/score/threadimpl.h>
#include <rtems/score/threadqimpl.h>
#include <rtems/config.h>

RTEMS_STATIC_ASSERT(
  sizeof(MPCI_Internal_packet) <= MP_PACKET_MINIMUM_PACKET_SIZE,
  MPCI_Internal_packet
);

/**
 *  This is the core semaphore which the MPCI Receive Server blocks on.
 */
CORE_semaphore_Control _MPCI_Semaphore;

void _MPCI_Handler_initialization(
  uint32_t   timeout_status
)
{
  CORE_semaphore_Attributes   attributes;
  MPCI_Control               *users_mpci_table;

  users_mpci_table = _Configuration_MP_table->User_mpci_table;

  if ( _System_state_Is_multiprocessing && !users_mpci_table )
    _Terminate(
      INTERNAL_ERROR_CORE,
      true,
      INTERNAL_ERROR_NO_MPCI
    );

  _MPCI_table = users_mpci_table;

  if ( !_System_state_Is_multiprocessing )
    return;

  /*
   *  Register the MP Process Packet routine.
   */

  _MPCI_Register_packet_processor(
    MP_PACKET_MPCI_INTERNAL,
    _MPCI_Internal_packets_Process_packet
  );

  /*
   *  Create the counting semaphore used by the MPCI Receive Server.
   */

  attributes.discipline = CORE_SEMAPHORE_DISCIPLINES_FIFO;

  _CORE_semaphore_Initialize(
    &_MPCI_Semaphore,
    &attributes,              /* the_semaphore_attributes */
    0                         /* initial_value */
  );

  _Thread_queue_Initialize(
    &_MPCI_Remote_blocked_threads,
    THREAD_QUEUE_DISCIPLINE_FIFO,
    STATES_WAITING_FOR_RPC_REPLY,
    timeout_status
  );
}

void _MPCI_Create_server( void )
{
  Objects_Name name;


  if ( !_System_state_Is_multiprocessing )
    return;

  /*
   *  Initialize the MPCI Receive Server
   */

  _MPCI_Receive_server_tcb = _Thread_Internal_allocate();

  name.name_u32 = _Objects_Build_name( 'M', 'P', 'C', 'I' );
  _Thread_Initialize(
    &_Thread_Internal_information,
    _MPCI_Receive_server_tcb,
    _Scheduler_Get_by_CPU_index( _SMP_Get_current_processor() ),
    NULL,        /* allocate the stack */
    _Stack_Minimum() +
      CPU_MPCI_RECEIVE_SERVER_EXTRA_STACK +
      _Configuration_MP_table->extra_mpci_receive_server_stack,
    CPU_ALL_TASKS_ARE_FP,
    PRIORITY_MINIMUM,
    false,       /* no preempt */
    THREAD_CPU_BUDGET_ALGORITHM_NONE,
    NULL,        /* no budget algorithm callout */
    0,           /* all interrupts enabled */
    name
  );

  _Thread_Start(
    _MPCI_Receive_server_tcb,
    THREAD_START_NUMERIC,
    (void *) _MPCI_Receive_server,
    NULL,
    0,
    NULL
  );
}

void _MPCI_Initialization ( void )
{
  (*_MPCI_table->initialization)();
}

void _MPCI_Register_packet_processor(
  MP_packet_Classes      the_class,
  MPCI_Packet_processor  the_packet_processor

)
{
  _MPCI_Packet_processors[ the_class ] = the_packet_processor;
}

MP_packet_Prefix *_MPCI_Get_packet ( void )
{
  MP_packet_Prefix  *the_packet;

  (*_MPCI_table->get_packet)( &the_packet );

  if ( the_packet == NULL )
    _Terminate(
      INTERNAL_ERROR_CORE,
      true,
      INTERNAL_ERROR_OUT_OF_PACKETS
    );

  /*
   *  Put in a default timeout that will be used for
   *  all packets that do not otherwise have a timeout.
   */

  the_packet->timeout = MPCI_DEFAULT_TIMEOUT;

  return the_packet;
}

void _MPCI_Return_packet (
  MP_packet_Prefix   *the_packet
)
{
  (*_MPCI_table->return_packet)( the_packet );
}

void _MPCI_Send_process_packet (
  uint32_t            destination,
  MP_packet_Prefix   *the_packet
)
{
  the_packet->source_tid = _Thread_Executing->Object.id;
  the_packet->to_convert =
     ( the_packet->to_convert - sizeof(MP_packet_Prefix) ) / sizeof(uint32_t);

  (*_MPCI_table->send_packet)( destination, the_packet );
}

uint32_t   _MPCI_Send_request_packet (
  uint32_t            destination,
  MP_packet_Prefix   *the_packet,
  States_Control      extra_state
)
{
  Thread_Control *executing = _Thread_Executing;

  the_packet->source_tid      = executing->Object.id;
  the_packet->source_priority = executing->current_priority;
  the_packet->to_convert =
     ( the_packet->to_convert - sizeof(MP_packet_Prefix) ) / sizeof(uint32_t);

  executing->Wait.id = the_packet->id;

  executing->Wait.queue = &_MPCI_Remote_blocked_threads;

  _Thread_Disable_dispatch();

    (*_MPCI_table->send_packet)( destination, the_packet );

    _Thread_queue_Enter_critical_section( &_MPCI_Remote_blocked_threads );

    /*
     *  See if we need a default timeout
     */

    if (the_packet->timeout == MPCI_DEFAULT_TIMEOUT)
        the_packet->timeout = _MPCI_table->default_timeout;

    _Thread_queue_Enqueue(
      &_MPCI_Remote_blocked_threads,
      executing,
      the_packet->timeout
    );

    executing->current_state =
      _States_Set( extra_state, executing->current_state );

  _Thread_Enable_dispatch();

  return executing->Wait.return_code;
}

void _MPCI_Send_response_packet (
  uint32_t            destination,
  MP_packet_Prefix   *the_packet
)
{
  the_packet->source_tid = _Thread_Executing->Object.id;

  (*_MPCI_table->send_packet)( destination, the_packet );
}

MP_packet_Prefix  *_MPCI_Receive_packet ( void )
{
  MP_packet_Prefix  *the_packet;

  (*_MPCI_table->receive_packet)( &the_packet );

  return the_packet;
}

Thread_Control *_MPCI_Process_response (
  MP_packet_Prefix  *the_packet
)
{
  Thread_Control    *the_thread;
  Objects_Locations  location;

  the_thread = _Thread_Get( the_packet->id, &location );
  switch ( location ) {
    case OBJECTS_ERROR:
#if defined(RTEMS_MULTIPROCESSING)
    case OBJECTS_REMOTE:
#endif
      the_thread = NULL;          /* IMPOSSIBLE */
      break;
    case OBJECTS_LOCAL:
      _Thread_queue_Extract( &_MPCI_Remote_blocked_threads, the_thread );
      the_thread->Wait.return_code = the_packet->return_code;
      _Objects_Put_without_thread_dispatch( &the_thread->Object );
    break;
  }

  return the_thread;
}

/*
 *  _MPCI_Receive_server
 *
 */

Thread _MPCI_Receive_server(
  uint32_t   ignored
)
{

  MP_packet_Prefix         *the_packet;
  MPCI_Packet_processor     the_function;
  Thread_Control           *executing;

  executing = _Thread_Get_executing();

  for ( ; ; ) {

    executing->receive_packet = NULL;

    _Thread_Disable_dispatch();
    _CORE_semaphore_Seize(
      &_MPCI_Semaphore,
      executing,
      0,
      true,
      WATCHDOG_NO_TIMEOUT
    );
    _Thread_Enable_dispatch();

    for ( ; ; ) {
      the_packet = _MPCI_Receive_packet();

      if ( !the_packet )
        break;

      executing->receive_packet = the_packet;

      if ( !_Mp_packet_Is_valid_packet_class ( the_packet->the_class ) )
        break;

      the_function = _MPCI_Packet_processors[ the_packet->the_class ];

      if ( !the_function )
        _Terminate(
          INTERNAL_ERROR_CORE,
          true,
          INTERNAL_ERROR_BAD_PACKET
        );

        (*the_function)( the_packet );
    }
  }

  return 0;   /* unreached - only to remove warnings */
}

void _MPCI_Announce ( void )
{
  _Thread_Disable_dispatch();
  (void) _CORE_semaphore_Surrender( &_MPCI_Semaphore, 0, 0 );
  _Thread_Enable_dispatch();
}

void _MPCI_Internal_packets_Send_process_packet (
   MPCI_Internal_Remote_operations operation
)
{
  MPCI_Internal_packet *the_packet;

  switch ( operation ) {

    case MPCI_PACKETS_SYSTEM_VERIFY:

      the_packet                    = _MPCI_Internal_packets_Get_packet();
      the_packet->Prefix.the_class  = MP_PACKET_MPCI_INTERNAL;
      the_packet->Prefix.length     = sizeof ( MPCI_Internal_packet );
      the_packet->Prefix.to_convert = sizeof ( MPCI_Internal_packet );
      the_packet->operation         = operation;

      the_packet->maximum_nodes = _Objects_Maximum_nodes;

      the_packet->maximum_global_objects = _Objects_MP_Maximum_global_objects;

      _MPCI_Send_process_packet( MPCI_ALL_NODES, &the_packet->Prefix );
      break;
  }
}

/*
 *  _MPCI_Internal_packets_Send_request_packet
 *
 *  This subprogram is not needed since there are no request
 *  packets to be sent by this manager.
 *
 */

/*
 *  _MPCI_Internal_packets_Send_response_packet
 *
 *  This subprogram is not needed since there are no response
 *  packets to be sent by this manager.
 *
 */

void _MPCI_Internal_packets_Process_packet (
  MP_packet_Prefix  *the_packet_prefix
)
{
  MPCI_Internal_packet *the_packet;
  uint32_t                    maximum_nodes;
  uint32_t                    maximum_global_objects;

  the_packet = (MPCI_Internal_packet *) the_packet_prefix;

  switch ( the_packet->operation ) {

    case MPCI_PACKETS_SYSTEM_VERIFY:

      maximum_nodes          = the_packet->maximum_nodes;
      maximum_global_objects = the_packet->maximum_global_objects;
      if ( maximum_nodes != _Objects_Maximum_nodes ||
           maximum_global_objects != _Objects_MP_Maximum_global_objects ) {

        _MPCI_Return_packet( the_packet_prefix );

        _Terminate(
          INTERNAL_ERROR_CORE,
          true,
          INTERNAL_ERROR_INCONSISTENT_MP_INFORMATION
        );
      }

      _MPCI_Return_packet( the_packet_prefix );

      break;
  }
}

/*
 *  _MPCI_Internal_packets_Send_object_was_deleted
 *
 *  This subprogram is not needed since there are no objects
 *  deleted by this manager.
 *
 */

/*
 *  _MPCI_Internal_packets_Send_extract_proxy
 *
 *  This subprogram is not needed since there are no objects
 *  deleted by this manager.
 *
 */

MPCI_Internal_packet *_MPCI_Internal_packets_Get_packet ( void )
{
  return ( (MPCI_Internal_packet *) _MPCI_Get_packet() );
}

/* end of file */