comm_monitor.hh revision 13892:0182a0601f66 
1/*
2 * Copyright (c) 2012-2013, 2015, 2018 ARM Limited
3 * Copyright (c) 2016 Google Inc.
4 * Copyright (c) 2017, Centre National de la Recherche Scientifique
5 * All rights reserved.
6 *
7 * The license below extends only to copyright in the software and shall
8 * not be construed as granting a license to any other intellectual
9 * property including but not limited to intellectual property relating
10 * to a hardware implementation of the functionality of the software
11 * licensed hereunder.  You may use the software subject to the license
12 * terms below provided that you ensure that this notice is replicated
13 * unmodified and in its entirety in all distributions of the software,
14 * modified or unmodified, in source code or in binary form.
15 *
16 * Redistribution and use in source and binary forms, with or without
17 * modification, are permitted provided that the following conditions are
18 * met: redistributions of source code must retain the above copyright
19 * notice, this list of conditions and the following disclaimer;
20 * redistributions in binary form must reproduce the above copyright
21 * notice, this list of conditions and the following disclaimer in the
22 * documentation and/or other materials provided with the distribution;
23 * neither the name of the copyright holders nor the names of its
24 * contributors may be used to endorse or promote products derived from
25 * this software without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
30 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
31 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
32 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
33 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
34 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
35 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
36 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
37 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
38 *
39 * Authors: Thomas Grass
40 *          Andreas Hansson
41 *          Rahul Thakur
42 *          Pierre-Yves Peneau
43 */
44
45#ifndef __MEM_COMM_MONITOR_HH__
46#define __MEM_COMM_MONITOR_HH__
47
48#include "base/statistics.hh"
49#include "mem/port.hh"
50#include "params/CommMonitor.hh"
51#include "sim/probe/mem.hh"
52#include "sim/sim_object.hh"
53
54/**
55 * The communication monitor is a SimObject which can monitor statistics of
56 * the communication happening between two ports in the memory system.
57 *
58 * Currently the following stats are implemented: Histograms of read/write
59 * transactions, read/write burst lengths, read/write bandwidth,
60 * outstanding read/write requests, read latency and inter transaction time
61 * (read-read, write-write, read/write-read/write). Furthermore it allows
62 * to capture the number of accesses to an address over time ("heat map").
63 * All stats can be disabled from Python.
64 */
65class CommMonitor : public SimObject
66{
67
68  public: // Construction & SimObject interfaces
69
70    /** Parameters of communication monitor */
71    typedef CommMonitorParams Params;
72    const Params* params() const
73    { return reinterpret_cast<const Params*>(_params); }
74
75    /**
76     * Constructor based on the Python params
77     *
78     * @param params Python parameters
79     */
80    CommMonitor(Params* params);
81
82    void init() override;
83    void regStats() override;
84    void startup() override;
85    void regProbePoints() override;
86
87  public: // SimObject interfaces
88    Port &getPort(const std::string &if_name,
89                  PortID idx=InvalidPortID) override;
90
91  private:
92
93    /**
94     * Sender state class for the monitor so that we can annotate
95     * packets with a transmit time and receive time.
96     */
97    class CommMonitorSenderState : public Packet::SenderState
98    {
99
100      public:
101
102        /**
103         * Construct a new sender state and store the time so we can
104         * calculate round-trip latency.
105         *
106         * @param _transmitTime Time of packet transmission
107         */
108        CommMonitorSenderState(Tick _transmitTime)
109            : transmitTime(_transmitTime)
110        { }
111
112        /** Destructor */
113        ~CommMonitorSenderState() { }
114
115        /** Tick when request is transmitted */
116        Tick transmitTime;
117
118    };
119
120    /**
121     * This is the master port of the communication monitor. All recv
122     * functions call a function in CommMonitor, where the
123     * send function of the slave port is called. Besides this, these
124     * functions can also perform actions for capturing statistics.
125     */
126    class MonitorMasterPort : public MasterPort
127    {
128
129      public:
130
131        MonitorMasterPort(const std::string& _name, CommMonitor& _mon)
132            : MasterPort(_name, &_mon), mon(_mon)
133        { }
134
135      protected:
136
137        void recvFunctionalSnoop(PacketPtr pkt)
138        {
139            mon.recvFunctionalSnoop(pkt);
140        }
141
142        Tick recvAtomicSnoop(PacketPtr pkt)
143        {
144            return mon.recvAtomicSnoop(pkt);
145        }
146
147        bool recvTimingResp(PacketPtr pkt)
148        {
149            return mon.recvTimingResp(pkt);
150        }
151
152        void recvTimingSnoopReq(PacketPtr pkt)
153        {
154            mon.recvTimingSnoopReq(pkt);
155        }
156
157        void recvRangeChange()
158        {
159            mon.recvRangeChange();
160        }
161
162        bool isSnooping() const
163        {
164            return mon.isSnooping();
165        }
166
167        void recvReqRetry()
168        {
169            mon.recvReqRetry();
170        }
171
172        void recvRetrySnoopResp()
173        {
174            mon.recvRetrySnoopResp();
175        }
176
177      private:
178
179        CommMonitor& mon;
180
181    };
182
183    /** Instance of master port, facing the memory side */
184    MonitorMasterPort masterPort;
185
186    /**
187     * This is the slave port of the communication monitor. All recv
188     * functions call a function in CommMonitor, where the
189     * send function of the master port is called. Besides this, these
190     * functions can also perform actions for capturing statistics.
191     */
192    class MonitorSlavePort : public SlavePort
193    {
194
195      public:
196
197        MonitorSlavePort(const std::string& _name, CommMonitor& _mon)
198            : SlavePort(_name, &_mon), mon(_mon)
199        { }
200
201      protected:
202
203        void recvFunctional(PacketPtr pkt)
204        {
205            mon.recvFunctional(pkt);
206        }
207
208        Tick recvAtomic(PacketPtr pkt)
209        {
210            return mon.recvAtomic(pkt);
211        }
212
213        bool recvTimingReq(PacketPtr pkt)
214        {
215            return mon.recvTimingReq(pkt);
216        }
217
218        bool recvTimingSnoopResp(PacketPtr pkt)
219        {
220            return mon.recvTimingSnoopResp(pkt);
221        }
222
223        AddrRangeList getAddrRanges() const
224        {
225            return mon.getAddrRanges();
226        }
227
228        void recvRespRetry()
229        {
230            mon.recvRespRetry();
231        }
232
233        bool tryTiming(PacketPtr pkt)
234        {
235            return mon.tryTiming(pkt);
236        }
237
238      private:
239
240        CommMonitor& mon;
241
242    };
243
244    /** Instance of slave port, i.e. on the CPU side */
245    MonitorSlavePort slavePort;
246
247    void recvFunctional(PacketPtr pkt);
248
249    void recvFunctionalSnoop(PacketPtr pkt);
250
251    Tick recvAtomic(PacketPtr pkt);
252
253    Tick recvAtomicSnoop(PacketPtr pkt);
254
255    bool recvTimingReq(PacketPtr pkt);
256
257    bool recvTimingResp(PacketPtr pkt);
258
259    void recvTimingSnoopReq(PacketPtr pkt);
260
261    bool recvTimingSnoopResp(PacketPtr pkt);
262
263    void recvRetrySnoopResp();
264
265    AddrRangeList getAddrRanges() const;
266
267    bool isSnooping() const;
268
269    void recvReqRetry();
270
271    void recvRespRetry();
272
273    void recvRangeChange();
274
275    bool tryTiming(PacketPtr pkt);
276
277    /** Stats declarations, all in a struct for convenience. */
278    struct MonitorStats
279    {
280
281        /** Disable flag for burst length histograms **/
282        bool disableBurstLengthHists;
283
284        /** Histogram of read burst lengths */
285        Stats::Histogram readBurstLengthHist;
286
287        /** Histogram of write burst lengths */
288        Stats::Histogram writeBurstLengthHist;
289
290        /** Disable flag for the bandwidth histograms */
291        bool disableBandwidthHists;
292
293        /**
294         * Histogram for read bandwidth per sample window. The
295         * internal counter is an unsigned int rather than a stat.
296         */
297        unsigned int readBytes;
298        Stats::Histogram readBandwidthHist;
299        Stats::Formula averageReadBW;
300        Stats::Scalar totalReadBytes;
301
302        /**
303         * Histogram for write bandwidth per sample window. The
304         * internal counter is an unsigned int rather than a stat.
305         */
306        unsigned int writtenBytes;
307        Stats::Histogram writeBandwidthHist;
308        Stats::Formula averageWriteBW;
309        Stats::Scalar totalWrittenBytes;
310
311        /** Disable flag for latency histograms. */
312        bool disableLatencyHists;
313
314        /** Histogram of read request-to-response latencies */
315        Stats::Histogram readLatencyHist;
316
317        /** Histogram of write request-to-response latencies */
318        Stats::Histogram writeLatencyHist;
319
320        /** Disable flag for ITT distributions. */
321        bool disableITTDists;
322
323        /**
324         * Inter transaction time (ITT) distributions. There are
325         * histograms of the time between two read, write or arbitrary
326         * accesses. The time of a request is the tick at which the
327         * request is forwarded by the monitor.
328         */
329        Stats::Distribution ittReadRead;
330        Stats::Distribution ittWriteWrite;
331        Stats::Distribution ittReqReq;
332        Tick timeOfLastRead;
333        Tick timeOfLastWrite;
334        Tick timeOfLastReq;
335
336        /** Disable flag for outstanding histograms. */
337        bool disableOutstandingHists;
338
339        /**
340         * Histogram of outstanding read requests. Counter for
341         * outstanding read requests is an unsigned integer because
342         * it should not be reset when stats are reset.
343         */
344        Stats::Histogram outstandingReadsHist;
345        unsigned int outstandingReadReqs;
346
347        /**
348         * Histogram of outstanding write requests. Counter for
349         * outstanding write requests is an unsigned integer because
350         * it should not be reset when stats are reset.
351         */
352        Stats::Histogram outstandingWritesHist;
353        unsigned int outstandingWriteReqs;
354
355        /** Disable flag for transaction histograms. */
356        bool disableTransactionHists;
357
358        /** Histogram of number of read transactions per time bin */
359        Stats::Histogram readTransHist;
360        unsigned int readTrans;
361
362        /** Histogram of number of timing write transactions per time bin */
363        Stats::Histogram writeTransHist;
364        unsigned int writeTrans;
365
366        /** Disable flag for address distributions. */
367        bool disableAddrDists;
368
369        /** Address mask for sources of read accesses to be captured */
370        const Addr readAddrMask;
371
372        /** Address mask for sources of write accesses to be captured */
373        const Addr writeAddrMask;
374
375        /**
376         * Histogram of number of read accesses to addresses over
377         * time.
378         */
379        Stats::SparseHistogram readAddrDist;
380
381        /**
382         * Histogram of number of write accesses to addresses over
383         * time.
384         */
385        Stats::SparseHistogram writeAddrDist;
386
387        /**
388         * Create the monitor stats and initialise all the members
389         * that are not statistics themselves, but used to control the
390         * stats or track values during a sample period.
391         */
392        MonitorStats(const CommMonitorParams* params) :
393            disableBurstLengthHists(params->disable_burst_length_hists),
394            disableBandwidthHists(params->disable_bandwidth_hists),
395            readBytes(0), writtenBytes(0),
396            disableLatencyHists(params->disable_latency_hists),
397            disableITTDists(params->disable_itt_dists),
398            timeOfLastRead(0), timeOfLastWrite(0), timeOfLastReq(0),
399            disableOutstandingHists(params->disable_outstanding_hists),
400            outstandingReadReqs(0), outstandingWriteReqs(0),
401            disableTransactionHists(params->disable_transaction_hists),
402            readTrans(0), writeTrans(0),
403            disableAddrDists(params->disable_addr_dists),
404            readAddrMask(params->read_addr_mask),
405            writeAddrMask(params->write_addr_mask)
406        { }
407
408        void updateReqStats(const ProbePoints::PacketInfo& pkt, bool is_atomic,
409                            bool expects_response);
410        void updateRespStats(const ProbePoints::PacketInfo& pkt, Tick latency,
411                             bool is_atomic);
412    };
413
414    /** This function is called periodically at the end of each time bin */
415    void samplePeriodic();
416
417    /** Periodic event called at the end of each simulation time bin */
418    EventFunctionWrapper samplePeriodicEvent;
419
420    /**
421     *@{
422     * @name Configuration
423     */
424
425    /** Length of simulation time bin*/
426    const Tick samplePeriodTicks;
427    /** Sample period in seconds */
428    const double samplePeriod;
429
430    /** @} */
431
432    /** Instantiate stats */
433    MonitorStats stats;
434
435  protected: // Probe points
436    /**
437     * @{
438     * @name Memory system probe points
439     */
440
441    /** Successfully forwarded request packet */
442    ProbePoints::PacketUPtr ppPktReq;
443
444    /** Successfully forwarded response packet */
445    ProbePoints::PacketUPtr ppPktResp;
446
447    /** @} */
448};
449
450#endif //__MEM_COMM_MONITOR_HH__
451