src/mem/comm_monitor.hh

   1 /*
   2  * Copyright (c) 2012-2013 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  * Redistribution and use in source and binary forms, with or without
  15  * modification, are permitted provided that the following conditions are
  16  * met: redistributions of source code must retain the above copyright
  17  * notice, this list of conditions and the following disclaimer;
  18  * redistributions in binary form must reproduce the above copyright
  19  * notice, this list of conditions and the following disclaimer in the
  20  * documentation and/or other materials provided with the distribution;
  21  * neither the name of the copyright holders nor the names of its
  22  * contributors may be used to endorse or promote products derived from
  23  * this software without specific prior written permission.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  26  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  27  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  28  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  29  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  30  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  31  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  32  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  33  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  34  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  35  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  36  *
  37  * Authors: Thomas Grass
  38  *          Andreas Hansson
  39  */
  40
  41 #ifndef __MEM_COMM_MONITOR_HH__
  42 #define __MEM_COMM_MONITOR_HH__
  43
  44 #include "base/statistics.hh"
  45 #include "base/time.hh"
  46 #include "mem/mem_object.hh"
  47 #include "mem/stack_dist_calc.hh"
  48 #include "params/CommMonitor.hh"
  49 #include "proto/protoio.hh"
  50 #include "sim/system.hh"
  51
  52 /**
  53  * The communication monitor is a MemObject which can monitor statistics of
  54  * the communication happening between two ports in the memory system.
  55  *
  56  * Currently the following stats are implemented: Histograms of read/write
  57  * transactions, read/write burst lengths, read/write bandwidth,
  58  * outstanding read/write requests, read latency and inter transaction time
  59  * (read-read, write-write, read/write-read/write). Furthermore it allows
  60  * to capture the number of accesses to an address over time ("heat map").
  61  * All stats can be disabled from Python.
  62  */
  63 class CommMonitor : public MemObject
  64 {
  65
  66   public:
  67
  68     /** Parameters of communication monitor */
  69     typedef CommMonitorParams Params;
  70     const Params* params() const
  71     { return reinterpret_cast<const Params*>(_params); }
  72
  73     /**
  74      * Constructor based on the Python params
  75      *
  76      * @param params Python parameters
  77      */
  78     CommMonitor(Params* params);
  79
  80     /** Destructor */
  81     ~CommMonitor();
  82
  83     /**
  84      * Callback to flush and close all open output streams on exit. If
  85      * we were calling the destructor it could be done there.
  86      */
  87     void closeStreams();
  88
  89     virtual BaseMasterPort& getMasterPort(const std::string& if_name,
  90                                           PortID idx = InvalidPortID);
  91
  92     virtual BaseSlavePort& getSlavePort(const std::string& if_name,
  93                                         PortID idx = InvalidPortID);
  94
  95     virtual void init();
  96
  97     /** Register statistics */
  98     void regStats();
  99
 100   private:
 101
 102     /**
 103      * Sender state class for the monitor so that we can annotate
 104      * packets with a transmit time and receive time.
 105      */
 106     class CommMonitorSenderState : public Packet::SenderState
 107     {
 108
 109       public:
 110
 111         /**
 112          * Construct a new sender state and store the time so we can
 113          * calculate round-trip latency.
 114          *
 115          * @param _transmitTime Time of packet transmission
 116          */
 117         CommMonitorSenderState(Tick _transmitTime)
 118             : transmitTime(_transmitTime)
 119         { }
 120
 121         /** Destructor */
 122         ~CommMonitorSenderState() { }
 123
 124         /** Tick when request is transmitted */
 125         Tick transmitTime;
 126
 127     };
 128
 129     /**
 130      * This is the master port of the communication monitor. All recv
 131      * functions call a function in CommMonitor, where the
 132      * send function of the slave port is called. Besides this, these
 133      * functions can also perform actions for capturing statistics.
 134      */
 135     class MonitorMasterPort : public MasterPort
 136     {
 137
 138       public:
 139
 140         MonitorMasterPort(const std::string& _name, CommMonitor& _mon)
 141             : MasterPort(_name, &_mon), mon(_mon)
 142         { }
 143
 144       protected:
 145
 146         void recvFunctionalSnoop(PacketPtr pkt)
 147         {
 148             mon.recvFunctionalSnoop(pkt);
 149         }
 150
 151         Tick recvAtomicSnoop(PacketPtr pkt)
 152         {
 153             return mon.recvAtomicSnoop(pkt);
 154         }
 155
 156         bool recvTimingResp(PacketPtr pkt)
 157         {
 158             return mon.recvTimingResp(pkt);
 159         }
 160
 161         void recvTimingSnoopReq(PacketPtr pkt)
 162         {
 163             mon.recvTimingSnoopReq(pkt);
 164         }
 165
 166         void recvRangeChange()
 167         {
 168             mon.recvRangeChange();
 169         }
 170
 171         bool isSnooping() const
 172         {
 173             return mon.isSnooping();
 174         }
 175
 176         void recvRetry()
 177         {
 178             mon.recvRetryMaster();
 179         }
 180
 181       private:
 182
 183         CommMonitor& mon;
 184
 185     };
 186
 187     /** Instance of master port, facing the memory side */
 188     MonitorMasterPort masterPort;
 189
 190     /**
 191      * This is the slave port of the communication monitor. All recv
 192      * functions call a function in CommMonitor, where the
 193      * send function of the master port is called. Besides this, these
 194      * functions can also perform actions for capturing statistics.
 195      */
 196     class MonitorSlavePort : public SlavePort
 197     {
 198
 199       public:
 200
 201         MonitorSlavePort(const std::string& _name, CommMonitor& _mon)
 202             : SlavePort(_name, &_mon), mon(_mon)
 203         { }
 204
 205       protected:
 206
 207         void recvFunctional(PacketPtr pkt)
 208         {
 209             mon.recvFunctional(pkt);
 210         }
 211
 212         Tick recvAtomic(PacketPtr pkt)
 213         {
 214             return mon.recvAtomic(pkt);
 215         }
 216
 217         bool recvTimingReq(PacketPtr pkt)
 218         {
 219             return mon.recvTimingReq(pkt);
 220         }
 221
 222         bool recvTimingSnoopResp(PacketPtr pkt)
 223         {
 224             return mon.recvTimingSnoopResp(pkt);
 225         }
 226
 227         AddrRangeList getAddrRanges() const
 228         {
 229             return mon.getAddrRanges();
 230         }
 231
 232         void recvRetry()
 233         {
 234             mon.recvRetrySlave();
 235         }
 236
 237       private:
 238
 239         CommMonitor& mon;
 240
 241     };
 242
 243     /** Instance of slave port, i.e. on the CPU side */
 244     MonitorSlavePort slavePort;
 245
 246     void recvFunctional(PacketPtr pkt);
 247
 248     void recvFunctionalSnoop(PacketPtr pkt);
 249
 250     Tick recvAtomic(PacketPtr pkt);
 251
 252     Tick recvAtomicSnoop(PacketPtr pkt);
 253
 254     bool recvTimingReq(PacketPtr pkt);
 255
 256     bool recvTimingResp(PacketPtr pkt);
 257
 258     void recvTimingSnoopReq(PacketPtr pkt);
 259
 260     bool recvTimingSnoopResp(PacketPtr pkt);
 261
 262     AddrRangeList getAddrRanges() const;
 263
 264     bool isSnooping() const;
 265
 266     void recvRetryMaster();
 267
 268     void recvRetrySlave();
 269
 270     void recvRangeChange();
 271
 272     /** Stats declarations, all in a struct for convenience. */
 273     struct MonitorStats
 274     {
 275
 276         /** Disable flag for burst length historgrams **/
 277         bool disableBurstLengthHists;
 278
 279         /** Histogram of read burst lengths */
 280         Stats::Histogram readBurstLengthHist;
 281
 282         /** Histogram of write burst lengths */
 283         Stats::Histogram writeBurstLengthHist;
 284
 285         /** Disable flag for the bandwidth histograms */
 286         bool disableBandwidthHists;
 287
 288         /**
 289          * Histogram for read bandwidth per sample window. The
 290          * internal counter is an unsigned int rather than a stat.
 291          */
 292         unsigned int readBytes;
 293         Stats::Histogram readBandwidthHist;
 294         Stats::Formula averageReadBW;
 295         Stats::Scalar totalReadBytes;
 296
 297         /**
 298          * Histogram for write bandwidth per sample window. The
 299          * internal counter is an unsigned int rather than a stat.
 300          */
 301         unsigned int writtenBytes;
 302         Stats::Histogram writeBandwidthHist;
 303         Stats::Formula averageWriteBW;
 304         Stats::Scalar totalWrittenBytes;
 305
 306         /** Disable flag for latency histograms. */
 307         bool disableLatencyHists;
 308
 309         /** Histogram of read request-to-response latencies */
 310         Stats::Histogram readLatencyHist;
 311
 312         /** Histogram of write request-to-response latencies */
 313         Stats::Histogram writeLatencyHist;
 314
 315         /** Disable flag for ITT distributions. */
 316         bool disableITTDists;
 317
 318         /**
 319          * Inter transaction time (ITT) distributions. There are
 320          * histograms of the time between two read, write or arbitrary
 321          * accesses. The time of a request is the tick at which the
 322          * request is forwarded by the monitor.
 323          */
 324         Stats::Distribution ittReadRead;
 325         Stats::Distribution ittWriteWrite;
 326         Stats::Distribution ittReqReq;
 327         Tick timeOfLastRead;
 328         Tick timeOfLastWrite;
 329         Tick timeOfLastReq;
 330
 331         /** Disable flag for outstanding histograms. */
 332         bool disableOutstandingHists;
 333
 334         /**
 335          * Histogram of outstanding read requests. Counter for
 336          * outstanding read requests is an unsigned integer because
 337          * it should not be reset when stats are reset.
 338          */
 339         Stats::Histogram outstandingReadsHist;
 340         unsigned int outstandingReadReqs;
 341
 342         /**
 343          * Histogram of outstanding write requests. Counter for
 344          * outstanding write requests is an unsigned integer because
 345          * it should not be reset when stats are reset.
 346          */
 347         Stats::Histogram outstandingWritesHist;
 348         unsigned int outstandingWriteReqs;
 349
 350         /** Disable flag for transaction histograms. */
 351         bool disableTransactionHists;
 352
 353         /** Histogram of number of read transactions per time bin */
 354         Stats::Histogram readTransHist;
 355         unsigned int readTrans;
 356
 357         /** Histogram of number of timing write transactions per time bin */
 358         Stats::Histogram writeTransHist;
 359         unsigned int writeTrans;
 360
 361         /** Disable flag for address distributions. */
 362         bool disableAddrDists;
 363
 364         /**
 365          * Histogram of number of read accesses to addresses over
 366          * time.
 367          */
 368         Stats::SparseHistogram readAddrDist;
 369
 370         /**
 371          * Histogram of number of write accesses to addresses over
 372          * time.
 373          */
 374         Stats::SparseHistogram writeAddrDist;
 375
 376         /**
 377          * Create the monitor stats and initialise all the members
 378          * that are not statistics themselves, but used to control the
 379          * stats or track values during a sample period.
 380          */
 381         MonitorStats(const CommMonitorParams* params) :
 382             disableBurstLengthHists(params->disable_burst_length_hists),
 383             disableBandwidthHists(params->disable_bandwidth_hists),
 384             readBytes(0), writtenBytes(0),
 385             disableLatencyHists(params->disable_latency_hists),
 386             disableITTDists(params->disable_itt_dists),
 387             timeOfLastRead(0), timeOfLastWrite(0), timeOfLastReq(0),
 388             disableOutstandingHists(params->disable_outstanding_hists),
 389             outstandingReadReqs(0), outstandingWriteReqs(0),
 390             disableTransactionHists(params->disable_transaction_hists),
 391             readTrans(0), writeTrans(0),
 392             disableAddrDists(params->disable_addr_dists)
 393         { }
 394
 395     };
 396
 397     /** This function is called periodically at the end of each time bin */
 398     void samplePeriodic();
 399
 400     /** Schedule the first periodic event */
 401     void startup();
 402
 403     /** Periodic event called at the end of each simulation time bin */
 404     EventWrapper<CommMonitor, &CommMonitor::samplePeriodic> samplePeriodicEvent;
 405
 406     /** Length of simulation time bin*/
 407     Tick samplePeriodTicks;
 408     Time samplePeriod;
 409
 410     /** Address mask for sources of read accesses to be captured */
 411     Addr readAddrMask;
 412
 413     /** Address mask for sources of write accesses to be captured */
 414     Addr writeAddrMask;
 415
 416     /** Instantiate stats */
 417     MonitorStats stats;
 418
 419     /** Optional stack distance calculator */
 420     StackDistCalc* stackDistCalc;
 421
 422     /** Output stream for a potential trace. */
 423     ProtoOutputStream* traceStream;
 424
 425     /** The system in which the monitor lives */
 426     System *system;
 427 };
 428
 429 #endif //__MEM_COMM_MONITOR_HH__