sim-events.c

这个是LINUX下的GDB调度工具的源码

  new_event->data = data;
  new_event->handler = handler;
  /* data */
  if (events->resume_wallclock == 0)
    new_event->wallclock = (events->elapsed_wallclock + delta_ms_time);
  else
    new_event->wallclock = (events->elapsed_wallclock
			    + sim_elapsed_time_since (events->resume_wallclock)
			    + delta_ms_time);
  /* insert */
  new_event->next = events->watchpoints;
  events->watchpoints = new_event;
  events->work_pending = 1;
  ETRACE ((_ETRACE,
	  "event watching clock at %ld - tag 0x%lx - wallclock %ld, handler 0x%lx, data 0x%lx\n",
	   (long)sim_events_time (sd),
	   (long)new_event,
	   (long)new_event->wallclock,
	   (long)new_event->handler,
	   (long)new_event->data));
  return new_event;
}
#endif


#if EXTERN_SIM_EVENTS_P
sim_event *
sim_events_watch_sim (SIM_DESC sd,
		      void *host_addr,
		      int nr_bytes,
		      int byte_order,
		      int is_within,
		      unsigned64 lb,
		      unsigned64 ub,
		      sim_event_handler *handler,
		      void *data)
{
  sim_events *events = STATE_EVENTS (sd);
  sim_event *new_event = sim_events_zalloc (sd);
  /* type */
  switch (byte_order)
    {
    case 0:
      switch (nr_bytes)
	{
	case 1: new_event->watching = watch_sim_host_1; break;
	case 2: new_event->watching = watch_sim_host_2; break;
	case 4: new_event->watching = watch_sim_host_4; break;
	case 8: new_event->watching = watch_sim_host_8; break;
	default: sim_io_error (sd, "sim_events_watch_sim - invalid nr bytes");
	}
      break;
    case BIG_ENDIAN:
      switch (nr_bytes)
	{
	case 1: new_event->watching = watch_sim_be_1; break;
	case 2: new_event->watching = watch_sim_be_2; break;
	case 4: new_event->watching = watch_sim_be_4; break;
	case 8: new_event->watching = watch_sim_be_8; break;
	default: sim_io_error (sd, "sim_events_watch_sim - invalid nr bytes");
	}
      break;
    case LITTLE_ENDIAN:
      switch (nr_bytes)
	{
	case 1: new_event->watching = watch_sim_le_1; break;
	case 2: new_event->watching = watch_sim_le_2; break;
	case 4: new_event->watching = watch_sim_le_4; break;
	case 8: new_event->watching = watch_sim_le_8; break;
	default: sim_io_error (sd, "sim_events_watch_sim - invalid nr bytes");
	}
      break;
    default:
      sim_io_error (sd, "sim_events_watch_sim - invalid byte order");
    }
  /* handler */
  new_event->data = data;
  new_event->handler = handler;
  /* data */
  new_event->host_addr = host_addr;
  new_event->lb = lb;
  new_event->lb64 = lb;
  new_event->ub = ub;
  new_event->ub64 = ub;
  new_event->is_within = (is_within != 0);
  /* insert */
  new_event->next = events->watchpoints;
  events->watchpoints = new_event;
  events->work_pending = 1;
  ETRACE ((_ETRACE,
	   "event watching host at %ld - tag 0x%lx - host-addr 0x%lx, 0x%lx..0x%lx, handler 0x%lx, data 0x%lx\n",
	   (long)sim_events_time (sd),
	   (long)new_event,
	   (long)new_event->host_addr,
	   (long)new_event->lb,
	   (long)new_event->ub,
	   (long)new_event->handler,
	   (long)new_event->data));
  return new_event;
}
#endif


#if EXTERN_SIM_EVENTS_P
sim_event *
sim_events_watch_core (SIM_DESC sd,
		       address_word core_addr,
		       unsigned core_map,
		       int nr_bytes,
		       int byte_order,
		       int is_within,
		       unsigned64 lb,
		       unsigned64 ub,
		       sim_event_handler *handler,
		       void *data)
{
  sim_events *events = STATE_EVENTS (sd);
  sim_event *new_event = sim_events_zalloc (sd);
  /* type */
  switch (byte_order)
    {
    case 0:
      switch (nr_bytes)
	{
	case 1: new_event->watching = watch_core_targ_1; break;
	case 2: new_event->watching = watch_core_targ_2; break;
	case 4: new_event->watching = watch_core_targ_4; break;
	case 8: new_event->watching = watch_core_targ_8; break;
	default: sim_io_error (sd, "sim_events_watch_core - invalid nr bytes");
	}
      break;
    case BIG_ENDIAN:
      switch (nr_bytes)
	{
	case 1: new_event->watching = watch_core_be_1; break;
	case 2: new_event->watching = watch_core_be_2; break;
	case 4: new_event->watching = watch_core_be_4; break;
	case 8: new_event->watching = watch_core_be_8; break;
	default: sim_io_error (sd, "sim_events_watch_core - invalid nr bytes");
	}
      break;
    case LITTLE_ENDIAN:
      switch (nr_bytes)
	{
	case 1: new_event->watching = watch_core_le_1; break;
	case 2: new_event->watching = watch_core_le_2; break;
	case 4: new_event->watching = watch_core_le_4; break;
	case 8: new_event->watching = watch_core_le_8; break;
	default: sim_io_error (sd, "sim_events_watch_core - invalid nr bytes");
	}
      break;
    default:
      sim_io_error (sd, "sim_events_watch_core - invalid byte order");
    }
  /* handler */
  new_event->data = data;
  new_event->handler = handler;
  /* data */
  new_event->core_addr = core_addr;
  new_event->core_map = core_map;
  new_event->lb = lb;
  new_event->lb64 = lb;
  new_event->ub = ub;
  new_event->ub64 = ub;
  new_event->is_within = (is_within != 0);
  /* insert */
  new_event->next = events->watchpoints;
  events->watchpoints = new_event;
  events->work_pending = 1;
  ETRACE ((_ETRACE,
	   "event watching host at %ld - tag 0x%lx - host-addr 0x%lx, 0x%lx..0x%lx, handler 0x%lx, data 0x%lx\n",
	   (long)sim_events_time (sd),
	   (long)new_event,
	   (long)new_event->host_addr,
	   (long)new_event->lb,
	   (long)new_event->ub,
	   (long)new_event->handler,
	   (long)new_event->data));
  return new_event;
}
#endif


#if EXTERN_SIM_EVENTS_P
void
sim_events_deschedule (SIM_DESC sd,
		       sim_event *event_to_remove)
{
  sim_events *events = STATE_EVENTS (sd);
  sim_event *to_remove = (sim_event*)event_to_remove;
  if (event_to_remove != NULL)
    {
      sim_event **queue = NULL;
      while ((queue = next_event_queue (sd, queue)) != NULL)
	{
	  sim_event **ptr_to_current;
	  for (ptr_to_current = queue;
	       *ptr_to_current != NULL && *ptr_to_current != to_remove;
	       ptr_to_current = &(*ptr_to_current)->next);
	  if (*ptr_to_current == to_remove)
	    {
	      sim_event *dead = *ptr_to_current;
	      *ptr_to_current = dead->next;
	      ETRACE ((_ETRACE,
		       "event/watch descheduled at %ld - tag 0x%lx - time %ld, handler 0x%lx, data 0x%lx%s%s\n",
		       (long) sim_events_time (sd),
		       (long) event_to_remove,
		       (long) dead->time_of_event,
		       (long) dead->handler,
		       (long) dead->data,
		       (dead->trace != NULL) ? ", " : "",
		       (dead->trace != NULL) ? dead->trace : ""));
	      sim_events_free (sd, dead);
	      update_time_from_event (sd);
	      SIM_ASSERT ((events->time_from_event >= 0) == (events->queue != NULL));
	      return;
	    }
	}
    }
  ETRACE ((_ETRACE,
	   "event/watch descheduled at %ld - tag 0x%lx - not found\n",
	   (long) sim_events_time (sd),
	   (long) event_to_remove));
}
#endif


STATIC_INLINE_SIM_EVENTS\
(int)
sim_watch_valid (SIM_DESC sd,
		 sim_event *to_do)
{
  switch (to_do->watching)
    {

#define WATCH_CORE(N,OP,EXT) \
      int ok; \
      unsigned_##N word = 0; \
      int nr_read = sim_core_read_buffer (sd, NULL, to_do->core_map, &word, \
					  to_do->core_addr, sizeof (word)); \
      OP (word); \
      ok = (nr_read == sizeof (unsigned_##N) \
	    && (to_do->is_within \
		== (word >= to_do->lb##EXT \
		    && word <= to_do->ub##EXT)));

    case watch_core_targ_1:
      {
	WATCH_CORE (1, T2H,);
	return ok;
      }
    case watch_core_targ_2:
      {
        WATCH_CORE (2, T2H,);
	return ok;
      }
    case watch_core_targ_4:
      {
        WATCH_CORE (4, T2H,);
	return ok;
      }
    case watch_core_targ_8:
      {
        WATCH_CORE (8, T2H,64);
	return ok;
      }

    case watch_core_be_1:
      {
        WATCH_CORE (1, BE2H,);
	return ok;
      }
    case watch_core_be_2:
      {
        WATCH_CORE (2, BE2H,);
	return ok;
      }
    case watch_core_be_4:
      {
        WATCH_CORE (4, BE2H,);
	return ok;
      }
    case watch_core_be_8:
      {
        WATCH_CORE (8, BE2H,64);
	return ok;
      }

    case watch_core_le_1:
      {
        WATCH_CORE (1, LE2H,);
	return ok;
      }
    case watch_core_le_2:
      {
        WATCH_CORE (2, LE2H,);
	return ok;
      }
    case watch_core_le_4:
      {
        WATCH_CORE (4, LE2H,);
	return ok;
      }
    case watch_core_le_8:
      {
        WATCH_CORE (8, LE2H,64);
	return ok;
      }
#undef WATCH_CORE

#define WATCH_SIM(N,OP,EXT) \
      int ok; \
      unsigned_##N word = *(unsigned_##N*)to_do->host_addr; \
      OP (word); \
      ok = (to_do->is_within \
	    == (word >= to_do->lb##EXT \
		&& word <= to_do->ub##EXT));

    case watch_sim_host_1:
      {
        WATCH_SIM (1, word = ,);
	return ok;
      }
    case watch_sim_host_2:
      {
        WATCH_SIM (2, word = ,);
	return ok;
      }
    case watch_sim_host_4:
      {
        WATCH_SIM (4, word = ,);
	return ok;
      }
    case watch_sim_host_8:
      {
        WATCH_SIM (8, word = ,64);
	return ok;
      }

    case watch_sim_be_1:
      {
        WATCH_SIM (1, BE2H,);
	return ok;
      }
    case watch_sim_be_2:
      {
        WATCH_SIM (2, BE2H,);
	return ok;
      }
    case watch_sim_be_4:
      {
        WATCH_SIM (4, BE2H,);
	return ok;
      }
    case watch_sim_be_8:
      {
        WATCH_SIM (8, BE2H,64);
	return ok;
      }

    case watch_sim_le_1:
      {
        WATCH_SIM (1, LE2H,);
	return ok;
      }
    case watch_sim_le_2:
      {
        WATCH_SIM (1, LE2H,);
	return ok;
      }
    case watch_sim_le_4:
      {
        WATCH_SIM (1, LE2H,);
	return ok;
      }
    case watch_sim_le_8:
      {
        WATCH_SIM (1, LE2H,64);
	return ok;
      }
#undef WATCH_SIM

    case watch_clock: /* wallclock */
      {
	unsigned long elapsed_time = sim_events_elapsed_time (sd);
	return (elapsed_time >= to_do->wallclock);
      }

    default:
      sim_io_error (sd, "sim_watch_valid - bad switch");
      break;

    }
  return 1;
}


INLINE_SIM_EVENTS\
(int)
sim_events_tick (SIM_DESC sd)
{
  sim_events *events = STATE_EVENTS (sd);

  /* this should only be called after the previous ticks have been
     fully processed */

  /* Advance the time but *only* if there is nothing to process */
  if (events->work_pending
      || events->time_from_event == 0)
    {
      events->nr_ticks_to_process += 1;
      return 1;
    }
  else
    {
      events->time_from_event -= 1;
      return 0;
    }
}


INLINE_SIM_EVENTS\
(int)
sim_events_tickn (SIM_DESC sd,
		  int n)
{
  sim_events *events = STATE_EVENTS (sd);
  SIM_ASSERT (n > 0);

  /* this should only be called after the previous ticks have been
     fully processed */

  /* Advance the time but *only* if there is nothing to process */
  if (events->work_pending || events->time_from_event < n)
    {
      events->nr_ticks_to_process += n;
      return 1;
    }
  else
    {
      events->time_from_event -= n;
      return 0;
    }
}


INLINE_SIM_EVENTS\
(void)
sim_events_slip (SIM_DESC sd,
		 int slip)
{
  sim_events *events = STATE_EVENTS (sd);
  SIM_ASSERT (slip > 0);

  /* Flag a ready event with work_pending instead of number of ticks
     to process so that the time continues to be correct */
  if (events->time_from_event < slip)
    {
      events->work_pending = 1;
    }
  events->time_from_event -= slip;
}


INLINE_SIM_EVENTS\
(void)
sim_events_preprocess (SIM_DESC sd,
		       int events_were_last,
		       int events_were_next)
{
  sim_events *events = STATE_EVENTS(sd);
  if (events_were_last)
    {
      /* Halted part way through event processing */
      ASSERT (events->nr_ticks_to_process != 0);
      /* The external world can't tell if the event that stopped the
         simulator was the last event to process. */
      ASSERT (events_were_next);
      sim_events_process (sd);
    }
  else if (events_were_next)
    {
      /* Halted by the last processor */
      if (sim_events_tick (sd))
	sim_events_process (sd);
    }
}


INLINE_SIM_EVENTS\
(void)
sim_events_process (SIM_DESC sd)
{
  sim_events *events = STATE_EVENTS(sd);
  signed64 event_time = sim_events_time(sd);

  /* Clear work_pending before checking nr_held.  Clearing
     work_pending after nr_held (with out a lock could loose an
     event). */
  events->work_pending = 0;

  /* move any events that were asynchronously queued by any signal
     handlers onto the real event queue.  */
  if (events->nr_held > 0)
    {
      int i;
      
#if defined(HAVE_SIGPROCMASK) && defined(SIG_SETMASK)
      /*-LOCK-*/
      sigset_t old_mask;
      sigset_t new_mask;
      sigfillset(&new_mask);
      sigprocmask(SIG_SETMASK, &new_mask, &old_mask);
#endif

      for (i = 0; i < events->nr_held; i++)
	{
	  sim_event *entry = &events->held [i];
	  sim_events_schedule (sd,
			       entry->time_of_event,
			       entry->handler,
			       entry->data);
	}
      events->nr_held = 0;
      
#if defined(HAVE_SIGPROCMASK) && defined(SIG_SETMASK)
      /*-UNLOCK-*/
      sigprocmask(SIG_SETMASK, &old_mask, NULL);
#endif
      
    }
  
  /* Process any watchpoints. Be careful to allow a watchpoint to
     appear/disappear under our feet.
     To ensure that watchpoints are processed only once per cycle,
     they are moved onto a watched queue, this returned to the
     watchpoint queue when all queue processing has been
     completed. */
  while (events->watchpoints != NULL)
    {
      sim_event *to_do = events->watchpoints;
      events->watchpoints = to_do->next;
      if (sim_watch_valid (sd, to_do))
	{
	  sim_event_handler *handler = to_do->handler;
	  void *data = to_do->data;
	  ETRACE((_ETRACE,
		  "event issued at %ld - tag 0x%lx - handler 0x%lx, data 0x%lx%s%s\n",
		  (long) event_time,
		  (long) to_do,
		  (long) handler,
		  (long) data,
		  (to_do->trace != NULL) ? ", " : "",
		  (to_do->trace != NULL) ? to_do->trace : ""));
	  sim_events_free (sd, to_do);
	  handler (sd, data);
	}
      else
	{
	  to_do->next = events->watchedpoints;
	  events->watchedpoints = to_do;
	}
    }
  
  /* consume all events for this or earlier times.  Be careful to
     allow an event to appear/disappear under our feet */
  while (events->queue->time_of_event <
	 (event_time + events->nr_ticks_to_process))
    {
      sim_event *to_do = events->queue;
      sim_event_handler *handler = to_do->handler;
      void *data = to_do->data;
      events->queue = to_do->next;
      update_time_from_event (sd);
      ETRACE((_ETRACE,
	      "event issued at %ld - tag 0x%lx - handler 0x%lx, data 0x%lx%s%s\n",
	      (long) event_time,
	      (long) to_do,
	      (long) handler,
	      (long) data,
	      (to_do->trace != NULL) ? ", " : "",
	      (to_do->trace != NULL) ? to_do->trace : ""));
      sim_events_free (sd, to_do);
      handler (sd, data);
    }
  
  /* put things back where they belong ready for the next iteration */
  events->watchpoints = events->watchedpoints;
  events->watchedpoints = NULL;
  if (events->watchpoints != NULL)
    events->work_pending = 1;
  
  /* advance the time */
  SIM_ASSERT (events->time_from_event >= events->nr_ticks_to_process);
  SIM_ASSERT (events->queue != NULL); /* always poll event */
  events->time_from_event -= events->nr_ticks_to_process;

  /* this round of processing complete */
  events->nr_ticks_to_process = 0;
}

#endif