comm_monitor.hh revision 13784:1941dc118243 
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/mem_object.hh"
50#include "params/CommMonitor.hh"
51#include "sim/probe/mem.hh"
52
53/**
54 * The communication monitor is a MemObject which can monitor statistics of
55 * the communication happening between two ports in the memory system.
56 *
57 * Currently the following stats are implemented: Histograms of read/write
58 * transactions, read/write burst lengths, read/write bandwidth,
59 * outstanding read/write requests, read latency and inter transaction time
60 * (read-read, write-write, read/write-read/write). Furthermore it allows
61 * to capture the number of accesses to an address over time ("heat map").
62 * All stats can be disabled from Python.
63 */
64class CommMonitor : public MemObject
65{
66
67  public: // Construction & SimObject interfaces
68
69    /** Parameters of communication monitor */
70    typedef CommMonitorParams Params;
71    const Params* params() const
72    { return reinterpret_cast<const Params*>(_params); }
73
74    /**
75     * Constructor based on the Python params
76     *
77     * @param params Python parameters
78     */
79    CommMonitor(Params* params);
80
81    void init() override;
82    void regStats() override;
83    void startup() override;
84    void regProbePoints() override;
85
86  public: // MemObject interfaces
87    Port &getPort(const std::string &if_name,
88                  PortID idx=InvalidPortID) override;
89
90  private:
91
92    /**
93     * Sender state class for the monitor so that we can annotate
94     * packets with a transmit time and receive time.
95     */
96    class CommMonitorSenderState : public Packet::SenderState
97    {
98
99      public:
100
101        /**
102         * Construct a new sender state and store the time so we can
103         * calculate round-trip latency.
104         *
105         * @param _transmitTime Time of packet transmission
106         */
107        CommMonitorSenderState(Tick _transmitTime)
108            : transmitTime(_transmitTime)
109        { }
110
111        /** Destructor */
112        ~CommMonitorSenderState() { }
113
114        /** Tick when request is transmitted */
115        Tick transmitTime;
116
117    };
118
119    /**
120     * This is the master port of the communication monitor. All recv
121     * functions call a function in CommMonitor, where the
122     * send function of the slave port is called. Besides this, these
123     * functions can also perform actions for capturing statistics.
124     */
125    class MonitorMasterPort : public MasterPort
126    {
127
128      public:
129
130        MonitorMasterPort(const std::string& _name, CommMonitor& _mon)
131            : MasterPort(_name, &_mon), mon(_mon)
132        { }
133
134      protected:
135
136        void recvFunctionalSnoop(PacketPtr pkt)
137        {
138            mon.recvFunctionalSnoop(pkt);
139        }
140
141        Tick recvAtomicSnoop(PacketPtr pkt)
142        {
143            return mon.recvAtomicSnoop(pkt);
144        }
145
146        bool recvTimingResp(PacketPtr pkt)
147        {
148            return mon.recvTimingResp(pkt);
149        }
150
151        void recvTimingSnoopReq(PacketPtr pkt)
152        {
153            mon.recvTimingSnoopReq(pkt);
154        }
155
156        void recvRangeChange()
157        {
158            mon.recvRangeChange();
159        }
160
161        bool isSnooping() const
162        {
163            return mon.isSnooping();
164        }
165
166        void recvReqRetry()
167        {
168            mon.recvReqRetry();
169        }
170
171        void recvRetrySnoopResp()
172        {
173            mon.recvRetrySnoopResp();
174        }
175
176      private:
177
178        CommMonitor& mon;
179
180    };
181
182    /** Instance of master port, facing the memory side */
183    MonitorMasterPort masterPort;
184
185    /**
186     * This is the slave port of the communication monitor. All recv
187     * functions call a function in CommMonitor, where the
188     * send function of the master port is called. Besides this, these
189     * functions can also perform actions for capturing statistics.
190     */
191    class MonitorSlavePort : public SlavePort
192    {
193
194      public:
195
196        MonitorSlavePort(const std::string& _name, CommMonitor& _mon)
197            : SlavePort(_name, &_mon), mon(_mon)
198        { }
199
200      protected:
201
202        void recvFunctional(PacketPtr pkt)
203        {
204            mon.recvFunctional(pkt);
205        }
206
207        Tick recvAtomic(PacketPtr pkt)
208        {
209            return mon.recvAtomic(pkt);
210        }
211
212        bool recvTimingReq(PacketPtr pkt)
213        {
214            return mon.recvTimingReq(pkt);
215        }
216
217        bool recvTimingSnoopResp(PacketPtr pkt)
218        {
219            return mon.recvTimingSnoopResp(pkt);
220        }
221
222        AddrRangeList getAddrRanges() const
223        {
224            return mon.getAddrRanges();
225        }
226
227        void recvRespRetry()
228        {
229            mon.recvRespRetry();
230        }
231
232        bool tryTiming(PacketPtr pkt)
233        {
234            return mon.tryTiming(pkt);
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    void recvRetrySnoopResp();
263
264    AddrRangeList getAddrRanges() const;
265
266    bool isSnooping() const;
267
268    void recvReqRetry();
269
270    void recvRespRetry();
271
272    void recvRangeChange();
273
274    bool tryTiming(PacketPtr pkt);
275
276    /** Stats declarations, all in a struct for convenience. */
277    struct MonitorStats
278    {
279
280        /** Disable flag for burst length histograms **/
281        bool disableBurstLengthHists;
282
283        /** Histogram of read burst lengths */
284        Stats::Histogram readBurstLengthHist;
285
286        /** Histogram of write burst lengths */
287        Stats::Histogram writeBurstLengthHist;
288
289        /** Disable flag for the bandwidth histograms */
290        bool disableBandwidthHists;
291
292        /**
293         * Histogram for read bandwidth per sample window. The
294         * internal counter is an unsigned int rather than a stat.
295         */
296        unsigned int readBytes;
297        Stats::Histogram readBandwidthHist;
298        Stats::Formula averageReadBW;
299        Stats::Scalar totalReadBytes;
300
301        /**
302         * Histogram for write bandwidth per sample window. The
303         * internal counter is an unsigned int rather than a stat.
304         */
305        unsigned int writtenBytes;
306        Stats::Histogram writeBandwidthHist;
307        Stats::Formula averageWriteBW;
308        Stats::Scalar totalWrittenBytes;
309
310        /** Disable flag for latency histograms. */
311        bool disableLatencyHists;
312
313        /** Histogram of read request-to-response latencies */
314        Stats::Histogram readLatencyHist;
315
316        /** Histogram of write request-to-response latencies */
317        Stats::Histogram writeLatencyHist;
318
319        /** Disable flag for ITT distributions. */
320        bool disableITTDists;
321
322        /**
323         * Inter transaction time (ITT) distributions. There are
324         * histograms of the time between two read, write or arbitrary
325         * accesses. The time of a request is the tick at which the
326         * request is forwarded by the monitor.
327         */
328        Stats::Distribution ittReadRead;
329        Stats::Distribution ittWriteWrite;
330        Stats::Distribution ittReqReq;
331        Tick timeOfLastRead;
332        Tick timeOfLastWrite;
333        Tick timeOfLastReq;
334
335        /** Disable flag for outstanding histograms. */
336        bool disableOutstandingHists;
337
338        /**
339         * Histogram of outstanding read requests. Counter for
340         * outstanding read requests is an unsigned integer because
341         * it should not be reset when stats are reset.
342         */
343        Stats::Histogram outstandingReadsHist;
344        unsigned int outstandingReadReqs;
345
346        /**
347         * Histogram of outstanding write requests. Counter for
348         * outstanding write requests is an unsigned integer because
349         * it should not be reset when stats are reset.
350         */
351        Stats::Histogram outstandingWritesHist;
352        unsigned int outstandingWriteReqs;
353
354        /** Disable flag for transaction histograms. */
355        bool disableTransactionHists;
356
357        /** Histogram of number of read transactions per time bin */
358        Stats::Histogram readTransHist;
359        unsigned int readTrans;
360
361        /** Histogram of number of timing write transactions per time bin */
362        Stats::Histogram writeTransHist;
363        unsigned int writeTrans;
364
365        /** Disable flag for address distributions. */
366        bool disableAddrDists;
367
368        /** Address mask for sources of read accesses to be captured */
369        const Addr readAddrMask;
370
371        /** Address mask for sources of write accesses to be captured */
372        const Addr writeAddrMask;
373
374        /**
375         * Histogram of number of read accesses to addresses over
376         * time.
377         */
378        Stats::SparseHistogram readAddrDist;
379
380        /**
381         * Histogram of number of write accesses to addresses over
382         * time.
383         */
384        Stats::SparseHistogram writeAddrDist;
385
386        /**
387         * Create the monitor stats and initialise all the members
388         * that are not statistics themselves, but used to control the
389         * stats or track values during a sample period.
390         */
391        MonitorStats(const CommMonitorParams* params) :
392            disableBurstLengthHists(params->disable_burst_length_hists),
393            disableBandwidthHists(params->disable_bandwidth_hists),
394            readBytes(0), writtenBytes(0),
395            disableLatencyHists(params->disable_latency_hists),
396            disableITTDists(params->disable_itt_dists),
397            timeOfLastRead(0), timeOfLastWrite(0), timeOfLastReq(0),
398            disableOutstandingHists(params->disable_outstanding_hists),
399            outstandingReadReqs(0), outstandingWriteReqs(0),
400            disableTransactionHists(params->disable_transaction_hists),
401            readTrans(0), writeTrans(0),
402            disableAddrDists(params->disable_addr_dists),
403            readAddrMask(params->read_addr_mask),
404            writeAddrMask(params->write_addr_mask)
405        { }
406
407        void updateReqStats(const ProbePoints::PacketInfo& pkt, bool is_atomic,
408                            bool expects_response);
409        void updateRespStats(const ProbePoints::PacketInfo& pkt, Tick latency,
410                             bool is_atomic);
411    };
412
413    /** This function is called periodically at the end of each time bin */
414    void samplePeriodic();
415
416    /** Periodic event called at the end of each simulation time bin */
417    EventFunctionWrapper samplePeriodicEvent;
418
419    /**
420     *@{
421     * @name Configuration
422     */
423
424    /** Length of simulation time bin*/
425    const Tick samplePeriodTicks;
426    /** Sample period in seconds */
427    const double samplePeriod;
428
429    /** @} */
430
431    /** Instantiate stats */
432    MonitorStats stats;
433
434  protected: // Probe points
435    /**
436     * @{
437     * @name Memory system probe points
438     */
439
440    /** Successfully forwarded request packet */
441    ProbePoints::PacketUPtr ppPktReq;
442
443    /** Successfully forwarded response packet */
444    ProbePoints::PacketUPtr ppPktResp;
445
446    /** @} */
447};
448
449#endif //__MEM_COMM_MONITOR_HH__
450