comm_monitor.hh revision 11804:220375a47eeb 
1/*
2 * Copyright (c) 2012-2013, 2015 ARM Limited
3 * Copyright (c) 2016 Google Inc.
4 * All rights reserved.
5 *
6 * The license below extends only to copyright in the software and shall
7 * not be construed as granting a license to any other intellectual
8 * property including but not limited to intellectual property relating
9 * to a hardware implementation of the functionality of the software
10 * licensed hereunder.  You may use the software subject to the license
11 * terms below provided that you ensure that this notice is replicated
12 * unmodified and in its entirety in all distributions of the software,
13 * modified or unmodified, in source code or in binary form.
14 *
15 * Redistribution and use in source and binary forms, with or without
16 * modification, are permitted provided that the following conditions are
17 * met: redistributions of source code must retain the above copyright
18 * notice, this list of conditions and the following disclaimer;
19 * redistributions in binary form must reproduce the above copyright
20 * notice, this list of conditions and the following disclaimer in the
21 * documentation and/or other materials provided with the distribution;
22 * neither the name of the copyright holders nor the names of its
23 * contributors may be used to endorse or promote products derived from
24 * this software without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
27 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
28 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
29 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
30 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
31 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
32 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
33 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
34 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
35 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
36 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
37 *
38 * Authors: Thomas Grass
39 *          Andreas Hansson
40 *          Rahul Thakur
41 */
42
43#ifndef __MEM_COMM_MONITOR_HH__
44#define __MEM_COMM_MONITOR_HH__
45
46#include "base/statistics.hh"
47#include "mem/mem_object.hh"
48#include "params/CommMonitor.hh"
49#include "sim/probe/mem.hh"
50
51/**
52 * The communication monitor is a MemObject which can monitor statistics of
53 * the communication happening between two ports in the memory system.
54 *
55 * Currently the following stats are implemented: Histograms of read/write
56 * transactions, read/write burst lengths, read/write bandwidth,
57 * outstanding read/write requests, read latency and inter transaction time
58 * (read-read, write-write, read/write-read/write). Furthermore it allows
59 * to capture the number of accesses to an address over time ("heat map").
60 * All stats can be disabled from Python.
61 */
62class CommMonitor : public MemObject
63{
64
65  public: // Construction & SimObject interfaces
66
67    /** Parameters of communication monitor */
68    typedef CommMonitorParams Params;
69    const Params* params() const
70    { return reinterpret_cast<const Params*>(_params); }
71
72    /**
73     * Constructor based on the Python params
74     *
75     * @param params Python parameters
76     */
77    CommMonitor(Params* params);
78
79    void init() override;
80    void regStats() override;
81    void startup() override;
82    void regProbePoints() override;
83
84  public: // MemObject interfaces
85    BaseMasterPort& getMasterPort(const std::string& if_name,
86                                  PortID idx = InvalidPortID) override;
87
88    BaseSlavePort& getSlavePort(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      private:
234
235        CommMonitor& mon;
236
237    };
238
239    /** Instance of slave port, i.e. on the CPU side */
240    MonitorSlavePort slavePort;
241
242    void recvFunctional(PacketPtr pkt);
243
244    void recvFunctionalSnoop(PacketPtr pkt);
245
246    Tick recvAtomic(PacketPtr pkt);
247
248    Tick recvAtomicSnoop(PacketPtr pkt);
249
250    bool recvTimingReq(PacketPtr pkt);
251
252    bool recvTimingResp(PacketPtr pkt);
253
254    void recvTimingSnoopReq(PacketPtr pkt);
255
256    bool recvTimingSnoopResp(PacketPtr pkt);
257
258    void recvRetrySnoopResp();
259
260    AddrRangeList getAddrRanges() const;
261
262    bool isSnooping() const;
263
264    void recvReqRetry();
265
266    void recvRespRetry();
267
268    void recvRangeChange();
269
270    /** Stats declarations, all in a struct for convenience. */
271    struct MonitorStats
272    {
273
274        /** Disable flag for burst length historgrams **/
275        bool disableBurstLengthHists;
276
277        /** Histogram of read burst lengths */
278        Stats::Histogram readBurstLengthHist;
279
280        /** Histogram of write burst lengths */
281        Stats::Histogram writeBurstLengthHist;
282
283        /** Disable flag for the bandwidth histograms */
284        bool disableBandwidthHists;
285
286        /**
287         * Histogram for read bandwidth per sample window. The
288         * internal counter is an unsigned int rather than a stat.
289         */
290        unsigned int readBytes;
291        Stats::Histogram readBandwidthHist;
292        Stats::Formula averageReadBW;
293        Stats::Scalar totalReadBytes;
294
295        /**
296         * Histogram for write bandwidth per sample window. The
297         * internal counter is an unsigned int rather than a stat.
298         */
299        unsigned int writtenBytes;
300        Stats::Histogram writeBandwidthHist;
301        Stats::Formula averageWriteBW;
302        Stats::Scalar totalWrittenBytes;
303
304        /** Disable flag for latency histograms. */
305        bool disableLatencyHists;
306
307        /** Histogram of read request-to-response latencies */
308        Stats::Histogram readLatencyHist;
309
310        /** Histogram of write request-to-response latencies */
311        Stats::Histogram writeLatencyHist;
312
313        /** Disable flag for ITT distributions. */
314        bool disableITTDists;
315
316        /**
317         * Inter transaction time (ITT) distributions. There are
318         * histograms of the time between two read, write or arbitrary
319         * accesses. The time of a request is the tick at which the
320         * request is forwarded by the monitor.
321         */
322        Stats::Distribution ittReadRead;
323        Stats::Distribution ittWriteWrite;
324        Stats::Distribution ittReqReq;
325        Tick timeOfLastRead;
326        Tick timeOfLastWrite;
327        Tick timeOfLastReq;
328
329        /** Disable flag for outstanding histograms. */
330        bool disableOutstandingHists;
331
332        /**
333         * Histogram of outstanding read requests. Counter for
334         * outstanding read requests is an unsigned integer because
335         * it should not be reset when stats are reset.
336         */
337        Stats::Histogram outstandingReadsHist;
338        unsigned int outstandingReadReqs;
339
340        /**
341         * Histogram of outstanding write requests. Counter for
342         * outstanding write requests is an unsigned integer because
343         * it should not be reset when stats are reset.
344         */
345        Stats::Histogram outstandingWritesHist;
346        unsigned int outstandingWriteReqs;
347
348        /** Disable flag for transaction histograms. */
349        bool disableTransactionHists;
350
351        /** Histogram of number of read transactions per time bin */
352        Stats::Histogram readTransHist;
353        unsigned int readTrans;
354
355        /** Histogram of number of timing write transactions per time bin */
356        Stats::Histogram writeTransHist;
357        unsigned int writeTrans;
358
359        /** Disable flag for address distributions. */
360        bool disableAddrDists;
361
362        /** Address mask for sources of read accesses to be captured */
363        const Addr readAddrMask;
364
365        /** Address mask for sources of write accesses to be captured */
366        const Addr writeAddrMask;
367
368        /**
369         * Histogram of number of read accesses to addresses over
370         * time.
371         */
372        Stats::SparseHistogram readAddrDist;
373
374        /**
375         * Histogram of number of write accesses to addresses over
376         * time.
377         */
378        Stats::SparseHistogram writeAddrDist;
379
380        /**
381         * Create the monitor stats and initialise all the members
382         * that are not statistics themselves, but used to control the
383         * stats or track values during a sample period.
384         */
385        MonitorStats(const CommMonitorParams* params) :
386            disableBurstLengthHists(params->disable_burst_length_hists),
387            disableBandwidthHists(params->disable_bandwidth_hists),
388            readBytes(0), writtenBytes(0),
389            disableLatencyHists(params->disable_latency_hists),
390            disableITTDists(params->disable_itt_dists),
391            timeOfLastRead(0), timeOfLastWrite(0), timeOfLastReq(0),
392            disableOutstandingHists(params->disable_outstanding_hists),
393            outstandingReadReqs(0), outstandingWriteReqs(0),
394            disableTransactionHists(params->disable_transaction_hists),
395            readTrans(0), writeTrans(0),
396            disableAddrDists(params->disable_addr_dists),
397            readAddrMask(params->read_addr_mask),
398            writeAddrMask(params->write_addr_mask)
399        { }
400
401        void updateReqStats(const ProbePoints::PacketInfo& pkt, bool is_atomic,
402                            bool expects_response);
403        void updateRespStats(const ProbePoints::PacketInfo& pkt, Tick latency,
404                             bool is_atomic);
405    };
406
407    /** This function is called periodically at the end of each time bin */
408    void samplePeriodic();
409
410    /** Periodic event called at the end of each simulation time bin */
411    EventWrapper<CommMonitor, &CommMonitor::samplePeriodic> samplePeriodicEvent;
412
413    /**
414     *@{
415     * @name Configuration
416     */
417
418    /** Length of simulation time bin*/
419    const Tick samplePeriodTicks;
420    /** Sample period in seconds */
421    const double samplePeriod;
422
423    /** @} */
424
425    /** Instantiate stats */
426    MonitorStats stats;
427
428  protected: // Probe points
429    /**
430     * @{
431     * @name Memory system probe points
432     */
433
434    /** Successfully forwarded request packet */
435    ProbePoints::PacketUPtr ppPktReq;
436
437    /** Successfully forwarded response packet */
438    ProbePoints::PacketUPtr ppPktResp;
439
440    /** @} */
441};
442
443#endif //__MEM_COMM_MONITOR_HH__
444