/*
+ * Copyright (c) 2015 ARM Limited
+ * All rights reserved
+ *
+ * The license below extends only to copyright in the software and shall
+ * not be construed as granting a license to any other intellectual
+ * property including but not limited to intellectual property relating
+ * to a hardware implementation of the functionality of the software
+ * licensed hereunder. You may use the software subject to the license
+ * terms below provided that you ensure that this notice is replicated
+ * unmodified and in its entirety in all distributions of the software,
+ * modified or unmodified, in source code or in binary form.
+ *
* Copyright (c) 2001-2005 The Regents of The University of Michigan
* Copyright (c) 2010 Advanced Micro Devices, Inc.
* All rights reserved.
#ifndef __SIM_OBJECT_HH__
#define __SIM_OBJECT_HH__
-#include <iostream>
-#include <list>
-#include <map>
#include <string>
#include <vector>
-#include "enums/MemoryMode.hh"
#include "params/SimObject.hh"
+#include "sim/drain.hh"
#include "sim/eventq.hh"
+#include "sim/eventq_impl.hh"
#include "sim/serialize.hh"
-class BaseCPU;
-class Event;
+class EventManager;
+class ProbeManager;
/**
* Abstract superclass for simulation objects. Represents things that
* </ul>
* <li>SimObject::resetStats()
* <li>SimObject::startup()
- * <li>SimObject::resume() if resuming from a checkpoint.
- * </ol>
- *
- * An object's internal state needs to be drained when creating a
- * checkpoint, switching between CPU models, or switching between
- * timing models. Once the internal state has been drained from
- * <i>all</i> objects in the system, the objects are serialized to
- * disc or the configuration change takes place. The process works as
- * follows (see simulate.py for details):
- *
- * <ol>
- * <li>An instance of a CountedDrainEvent is created to keep track of
- * how many objects need to be drained. The object maintains an
- * internal counter that is decreased every time its
- * CountedDrainEvent::process() method is called. When the counter
- * reaches zero, the simulation is stopped.
- *
- * <li>Call SimObject::drain() for every object in the
- * system. Draining has completed if all of them return
- * zero. Otherwise, the sum of the return values is loaded into
- * the counter of the CountedDrainEvent. A pointer of the drain
- * event is passed as an argument to the drain() method.
- *
- * <li>Continue simulation. When an object has finished draining its
- * internal state, it calls CountedDrainEvent::process() on the
- * CountedDrainEvent. When counter in the CountedDrainEvent reaches
- * zero, the simulation stops.
- *
- * <li>Check if any object still needs draining, if so repeat the
- * process above.
- *
- * <li>Serialize objects, switch CPU model, or change timing model.
- *
- * <li>Call SimObject::resume() and continue the simulation.
+ * <li>Drainable::drainResume() if resuming from a checkpoint.
* </ol>
*
* @note Whenever a method is called on all objects in the simulator's
* SimObject.py). This has the effect of calling the method on the
* parent node <i>before</i> its children.
*/
-class SimObject : public EventManager, public Serializable
+class SimObject : public EventManager, public Serializable, public Drainable
{
- public:
- /**
- * Object drain/handover states
- *
- * An object starts out in the Running state. When the simulator
- * prepares to take a snapshot or prepares a CPU for handover, it
- * calls the drain() method to transfer the object into the
- * Draining or Drained state. If any object enters the Draining
- * state (drain() returning >0), simulation continues until it all
- * objects have entered the Drained.
- *
- * The before resuming simulation, the simulator calls resume() to
- * transfer the object to the Running state.
- *
- * \note Even though the state of an object (visible to the rest
- * of the world through getState()) could be used to determine if
- * all objects have entered the Drained state, the protocol is
- * actually a bit more elaborate. See drain() for details.
- */
- enum State {
- Running, /** Running normally */
- Draining, /** Draining buffers pending serialization/handover */
- Drained /** Buffers drained, ready for serialization/handover */
- };
-
- private:
- State state;
-
- protected:
- void changeState(State new_state) { state = new_state; }
-
- public:
- State getState() { return state; }
-
private:
typedef std::vector<SimObject *> SimObjectList;
/** List of all instantiated simulation objects. */
static SimObjectList simObjectList;
+ /** Manager coordinates hooking up probe points with listeners. */
+ ProbeManager *probeManager;
+
protected:
/** Cached copy of the object parameters. */
const SimObjectParams *_params;
typedef SimObjectParams Params;
const Params *params() const { return _params; }
SimObject(const Params *_params);
- virtual ~SimObject() {}
+ virtual ~SimObject();
public:
*
* @param cp Checkpoint to restore the state from.
*/
- virtual void loadState(Checkpoint *cp);
+ virtual void loadState(CheckpointIn &cp);
/**
* initState() is called on each SimObject when *not* restoring
*/
virtual void resetStats();
+ /**
+ * Register probe points for this object.
+ */
+ virtual void regProbePoints();
+
+ /**
+ * Register probe listeners for this object.
+ */
+ virtual void regProbeListeners();
+
+ /**
+ * Get the probe manager for this object.
+ */
+ ProbeManager *getProbeManager();
+
/**
* startup() is the final initialization call before simulation.
* All state is initialized (including unserialized state, if any,
virtual void startup();
/**
- * Serialize all SimObjects in the system.
+ * Provide a default implementation of the drain interface for
+ * objects that don't need draining.
*/
- static void serializeAll(std::ostream &os);
+ DrainState drain() override { return DrainState::Drained; }
/**
- * Determine if an object needs draining and register a drain
- * event.
- *
- * When draining the state of an object, the simulator calls drain
- * with a pointer to a drain event. If the object does not need
- * further simulation to drain internal buffers, it switched to
- * the Drained state and returns 0, otherwise it switches to the
- * Draining state and returns the number of times that it will
- * call Event::process() on the drain event. Most objects are
- * expected to return either 0 or 1.
- *
- * The default implementation simply switches to the Drained state
- * and returns 0.
+ * Write back dirty buffers to memory using functional writes.
*
- * @note An object that has entered the Drained state can be
- * disturbed by other objects in the system and consequently be
- * forced to enter the Draining state again. The simulator
- * therefore repeats the draining process until all objects return
- * 0 on the first call to drain().
+ * After returning, an object implementing this method should have
+ * written all its dirty data back to memory. This method is
+ * typically used to prepare a system with caches for
+ * checkpointing.
+ */
+ virtual void memWriteback() {};
+
+ /**
+ * Invalidate the contents of memory buffers.
*
- * @param drain_event Event to use to inform the simulator when
- * the draining has completed.
+ * When the switching to hardware virtualized CPU models, we need
+ * to make sure that we don't have any cached state in the system
+ * that might become stale when we return. This method is used to
+ * flush all such state back to main memory.
*
- * @return 0 if the object is ready for serialization now, >0 if
- * it needs further simulation.
+ * @warn This does <i>not</i> cause any dirty state to be written
+ * back to memory.
*/
- virtual unsigned int drain(Event *drain_event);
+ virtual void memInvalidate() {};
+
+ void serialize(CheckpointOut &cp) const override {};
+ void unserialize(CheckpointIn &cp) override {};
/**
- * Switch an object in the Drained stated into the Running state.
+ * Serialize all SimObjects in the system.
*/
- virtual void resume();
+ static void serializeAll(CheckpointOut &cp);
#ifdef DEBUG
public:
static SimObject *find(const char *name);
};
+/**
+ * Base class to wrap object resolving functionality.
+ *
+ * This can be provided to the serialization framework to allow it to
+ * map object names onto C++ objects.
+ */
+class SimObjectResolver
+{
+ public:
+ virtual ~SimObjectResolver() { }
+
+ // Find a SimObject given a full path name
+ virtual SimObject *resolveSimObject(const std::string &name) = 0;
+};
+
+#ifdef DEBUG
+void debugObjectBreak(const char *objs);
+#endif
+
#endif // __SIM_OBJECT_HH__