src/sim/sim_object.hh

   1 /*
   2  * Copyright (c) 2015 ARM Limited
   3  * All rights reserved
   4  *
   5  * The license below extends only to copyright in the software and shall
   6  * not be construed as granting a license to any other intellectual
   7  * property including but not limited to intellectual property relating
   8  * to a hardware implementation of the functionality of the software
   9  * licensed hereunder.  You may use the software subject to the license
  10  * terms below provided that you ensure that this notice is replicated
  11  * unmodified and in its entirety in all distributions of the software,
  12  * modified or unmodified, in source code or in binary form.
  13  *
  14  * Copyright (c) 2001-2005 The Regents of The University of Michigan
  15  * Copyright (c) 2010 Advanced Micro Devices, Inc.
  16  * All rights reserved.
  17  *
  18  * Redistribution and use in source and binary forms, with or without
  19  * modification, are permitted provided that the following conditions are
  20  * met: redistributions of source code must retain the above copyright
  21  * notice, this list of conditions and the following disclaimer;
  22  * redistributions in binary form must reproduce the above copyright
  23  * notice, this list of conditions and the following disclaimer in the
  24  * documentation and/or other materials provided with the distribution;
  25  * neither the name of the copyright holders nor the names of its
  26  * contributors may be used to endorse or promote products derived from
  27  * this software without specific prior written permission.
  28  *
  29  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  30  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  31  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  32  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  33  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  34  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  35  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  36  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  37  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  38  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  39  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  40  */
  41
  42 /* @file
  43  * User Console Definitions
  44  */
  45
  46 #ifndef __SIM_OBJECT_HH__
  47 #define __SIM_OBJECT_HH__
  48
  49 #include <string>
  50 #include <vector>
  51
  52 #include "base/stats/group.hh"
  53 #include "params/SimObject.hh"
  54 #include "sim/drain.hh"
  55 #include "sim/eventq.hh"
  56 #include "sim/port.hh"
  57 #include "sim/serialize.hh"
  58
  59 class EventManager;
  60 class ProbeManager;
  61
  62 /**
  63  * Abstract superclass for simulation objects.  Represents things that
  64  * correspond to physical components and can be specified via the
  65  * config file (CPUs, caches, etc.).
  66  *
  67  * SimObject initialization is controlled by the instantiate method in
  68  * src/python/m5/simulate.py. There are slightly different
  69  * initialization paths when starting the simulation afresh and when
  70  * loading from a checkpoint.  After instantiation and connecting
  71  * ports, simulate.py initializes the object using the following call
  72  * sequence:
  73  *
  74  * <ol>
  75  * <li>SimObject::init()
  76  * <li>SimObject::regStats()
  77  * <li><ul>
  78  *     <li>SimObject::initState() if starting afresh.
  79  *     <li>SimObject::loadState() if restoring from a checkpoint.
  80  *     </ul>
  81  * <li>SimObject::resetStats()
  82  * <li>SimObject::startup()
  83  * <li>Drainable::drainResume() if resuming from a checkpoint.
  84  * </ol>
  85  *
  86  * @note Whenever a method is called on all objects in the simulator's
  87  * object tree (e.g., init(), startup(), or loadState()), a pre-order
  88  * depth-first traversal is performed (see descendants() in
  89  * SimObject.py). This has the effect of calling the method on the
  90  * parent node <i>before</i> its children.
  91  */
  92 class SimObject : public EventManager, public Serializable, public Drainable,
  93                   public Stats::Group
  94 {
  95   private:
  96     typedef std::vector<SimObject *> SimObjectList;
  97
  98     /** List of all instantiated simulation objects. */
  99     static SimObjectList simObjectList;
 100
 101     /** Manager coordinates hooking up probe points with listeners. */
 102     ProbeManager *probeManager;
 103
 104   protected:
 105     /**
 106      * Cached copy of the object parameters.
 107      *
 108      * @ingroup api_simobject
 109      */
 110     const SimObjectParams *_params;
 111
 112   public:
 113     typedef SimObjectParams Params;
 114     /**
 115      * @ingroup api_simobject
 116      * @{
 117      */
 118     const Params *params() const { return _params; }
 119     SimObject(const Params *_params);
 120     /** @}*/ //end of the api_simobject group
 121     virtual ~SimObject();
 122
 123   public:
 124
 125     /**
 126      * @ingroup api_simobject
 127      */
 128     virtual const std::string name() const { return params()->name; }
 129
 130     /**
 131      * init() is called after all C++ SimObjects have been created and
 132      * all ports are connected.  Initializations that are independent
 133      * of unserialization but rely on a fully instantiated and
 134      * connected SimObject graph should be done here.
 135      *
 136      * @ingroup api_simobject
 137      */
 138     virtual void init();
 139
 140     /**
 141      * loadState() is called on each SimObject when restoring from a
 142      * checkpoint.  The default implementation simply calls
 143      * unserialize() if there is a corresponding section in the
 144      * checkpoint.  However, objects can override loadState() to get
 145      * other behaviors, e.g., doing other programmed initializations
 146      * after unserialize(), or complaining if no checkpoint section is
 147      * found.
 148      *
 149      * @param cp Checkpoint to restore the state from.
 150      *
 151      * @ingroup api_serialize
 152      */
 153     virtual void loadState(CheckpointIn &cp);
 154
 155     /**
 156      * initState() is called on each SimObject when *not* restoring
 157      * from a checkpoint.  This provides a hook for state
 158      * initializations that are only required for a "cold start".
 159      *
 160      * @ingroup api_serialize
 161      */
 162     virtual void initState();
 163
 164     /**
 165      * Register probe points for this object.
 166      *
 167      * @ingroup api_simobject
 168      */
 169     virtual void regProbePoints();
 170
 171     /**
 172      * Register probe listeners for this object.
 173      *
 174      * @ingroup api_simobject
 175      */
 176     virtual void regProbeListeners();
 177
 178     /**
 179      * Get the probe manager for this object.
 180      *
 181      * @ingroup api_simobject
 182      */
 183     ProbeManager *getProbeManager();
 184
 185     /**
 186      * Get a port with a given name and index. This is used at binding time
 187      * and returns a reference to a protocol-agnostic port.
 188      *
 189      * @param if_name Port name
 190      * @param idx Index in the case of a VectorPort
 191      *
 192      * @return A reference to the given port
 193      *
 194      * @ingroup api_simobject
 195      */
 196     virtual Port &getPort(const std::string &if_name,
 197                           PortID idx=InvalidPortID);
 198
 199     /**
 200      * startup() is the final initialization call before simulation.
 201      * All state is initialized (including unserialized state, if any,
 202      * such as the curTick() value), so this is the appropriate place to
 203      * schedule initial event(s) for objects that need them.
 204      *
 205      * @ingroup api_simobject
 206      */
 207     virtual void startup();
 208
 209     /**
 210      * Provide a default implementation of the drain interface for
 211      * objects that don't need draining.
 212      */
 213     DrainState drain() override { return DrainState::Drained; }
 214
 215     /**
 216      * Write back dirty buffers to memory using functional writes.
 217      *
 218      * After returning, an object implementing this method should have
 219      * written all its dirty data back to memory. This method is
 220      * typically used to prepare a system with caches for
 221      * checkpointing.
 222      *
 223      * @ingroup api_simobject
 224      */
 225     virtual void memWriteback() {};
 226
 227     /**
 228      * Invalidate the contents of memory buffers.
 229      *
 230      * When the switching to hardware virtualized CPU models, we need
 231      * to make sure that we don't have any cached state in the system
 232      * that might become stale when we return. This method is used to
 233      * flush all such state back to main memory.
 234      *
 235      * @warn This does <i>not</i> cause any dirty state to be written
 236      * back to memory.
 237      *
 238      * @ingroup api_simobject
 239      */
 240     virtual void memInvalidate() {};
 241
 242     void serialize(CheckpointOut &cp) const override {};
 243     void unserialize(CheckpointIn &cp) override {};
 244
 245     /**
 246      * Serialize all SimObjects in the system.
 247      */
 248     static void serializeAll(CheckpointOut &cp);
 249
 250 #ifdef DEBUG
 251   public:
 252     bool doDebugBreak;
 253     static void debugObjectBreak(const std::string &objs);
 254 #endif
 255
 256     /**
 257      * Find the SimObject with the given name and return a pointer to
 258      * it.  Primarily used for interactive debugging.  Argument is
 259      * char* rather than std::string to make it callable from gdb.
 260      *
 261      * @ingroup api_simobject
 262      */
 263     static SimObject *find(const char *name);
 264 };
 265
 266 /**
 267  * Base class to wrap object resolving functionality.
 268  *
 269  * This can be provided to the serialization framework to allow it to
 270  * map object names onto C++ objects.
 271  */
 272 class SimObjectResolver
 273 {
 274   public:
 275     virtual ~SimObjectResolver() { }
 276
 277     /**
 278      * Find a SimObject given a full path name
 279      *
 280      * @ingroup api_serialize
 281      */
 282     virtual SimObject *resolveSimObject(const std::string &name) = 0;
 283 };
 284
 285 #ifdef DEBUG
 286 void debugObjectBreak(const char *objs);
 287 #endif
 288
 289 #endif // __SIM_OBJECT_HH__