summaryrefslogtreecommitdiff
path: root/src/mem/comm_monitor.cc
blob: aea0286928f0841aafd81fb726952ac92420fd62 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
/*
 * Copyright (c) 2012 ARM Limited
 * All rights reserved
 *
 * The license below extends only to copyright in the software and shall
 * not be construed as granting a license to any other intellectual
 * property including but not limited to intellectual property relating
 * to a hardware implementation of the functionality of the software
 * licensed hereunder.  You may use the software subject to the license
 * terms below provided that you ensure that this notice is replicated
 * unmodified and in its entirety in all distributions of the software,
 * modified or unmodified, in source code or in binary form.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met: redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer;
 * redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution;
 * neither the name of the copyright holders nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Authors: Thomas Grass
 *          Andreas Hansson
 */

#include "debug/CommMonitor.hh"
#include "mem/comm_monitor.hh"
#include "sim/stats.hh"

CommMonitor::CommMonitor(Params* params)
    : MemObject(params),
      masterPort(name() + "-master", *this),
      slavePort(name() + "-slave", *this),
      samplePeriodicEvent(this),
      samplePeriodTicks(params->sample_period),
      readAddrMask(params->read_addr_mask),
      writeAddrMask(params->write_addr_mask),
      stats(params)
{
    // keep track of the sample period both in ticks and absolute time
    samplePeriod.setTick(params->sample_period);

    DPRINTF(CommMonitor,
            "Created monitor %s with sample period %d ticks (%f s)\n",
            name(), samplePeriodTicks, samplePeriod);
}

CommMonitor*
CommMonitorParams::create()
{
    return new CommMonitor(this);
}

void
CommMonitor::init()
{
    // make sure both sides of the monitor are connected
    if (!slavePort.isConnected() || !masterPort.isConnected())
        fatal("Communication monitor is not connected on both sides.\n");
}

BaseMasterPort&
CommMonitor::getMasterPort(const std::string& if_name, PortID idx)
{
    if (if_name == "master") {
        return masterPort;
    } else {
        return MemObject::getMasterPort(if_name, idx);
    }
}

BaseSlavePort&
CommMonitor::getSlavePort(const std::string& if_name, PortID idx)
{
    if (if_name == "slave") {
        return slavePort;
    } else {
        return MemObject::getSlavePort(if_name, idx);
    }
}

void
CommMonitor::recvFunctional(PacketPtr pkt)
{
    masterPort.sendFunctional(pkt);
}

void
CommMonitor::recvFunctionalSnoop(PacketPtr pkt)
{
    slavePort.sendFunctionalSnoop(pkt);
}

Tick
CommMonitor::recvAtomic(PacketPtr pkt)
{
    return masterPort.sendAtomic(pkt);
}

Tick
CommMonitor::recvAtomicSnoop(PacketPtr pkt)
{
    return slavePort.sendAtomicSnoop(pkt);
}

bool
CommMonitor::recvTimingReq(PacketPtr pkt)
{
    // should always see a request
    assert(pkt->isRequest());

    // Store relevant fields of packet, because packet may be modified
    // or even deleted when sendTiming() is called.
    bool isRead = pkt->isRead();
    bool isWrite = pkt->isWrite();
    unsigned size = pkt->getSize();
    Addr addr = pkt->getAddr();
    bool needsResponse = pkt->needsResponse();
    bool memInhibitAsserted = pkt->memInhibitAsserted();
    Packet::SenderState* senderState = pkt->senderState;

    // If a cache miss is served by a cache, a monitor near the memory
    // would see a request which needs a response, but this response
    // would be inhibited and not come back from the memory. Therefore
    // we additionally have to check the inhibit flag.
    if (needsResponse && !memInhibitAsserted && !stats.disableLatencyHists) {
        pkt->senderState = new CommMonitorSenderState(senderState,
                                                      curTick());
    }

    // Attempt to send the packet (always succeeds for inhibited
    // packets)
    bool successful = masterPort.sendTimingReq(pkt);

    // If not successful, restore the sender state
    if (!successful && needsResponse && !stats.disableLatencyHists) {
        delete pkt->senderState;
        pkt->senderState = senderState;
    }

    if (successful && isRead) {
        DPRINTF(CommMonitor, "Forwarded read request\n");

        // Increment number of observed read transactions
        if (!stats.disableTransactionHists) {
            ++stats.readTrans;
        }

        // Get sample of burst length
        if (!stats.disableBurstLengthHists) {
            stats.readBurstLengthHist.sample(size);
        }

        // Sample the masked address
        if (!stats.disableAddrDists) {
            stats.readAddrDist.sample(addr & readAddrMask);
        }

        // If it needs a response increment number of outstanding read
        // requests
        if (!stats.disableOutstandingHists && needsResponse) {
            ++stats.outstandingReadReqs;
        }

        if (!stats.disableITTDists) {
            // Sample value of read-read inter transaction time
            if (stats.timeOfLastRead != 0) {
                stats.ittReadRead.sample(curTick() - stats.timeOfLastRead);
            }
            stats.timeOfLastRead = curTick();

            // Sample value of req-req inter transaction time
            if (stats.timeOfLastReq != 0) {
                stats.ittReqReq.sample(curTick() - stats.timeOfLastReq);
            }
            stats.timeOfLastReq = curTick();
        }
    } else if (successful && isWrite) {
        DPRINTF(CommMonitor, "Forwarded write request\n");

        // Same as for reads
        if (!stats.disableTransactionHists) {
            ++stats.writeTrans;
        }

        if (!stats.disableBurstLengthHists) {
            stats.writeBurstLengthHist.sample(size);
        }

        // Update the bandwidth stats on the request
        if (!stats.disableBandwidthHists) {
            stats.writtenBytes += size;
            stats.totalWrittenBytes += size;
        }

        // Sample the masked write address
        if (!stats.disableAddrDists) {
            stats.writeAddrDist.sample(addr & writeAddrMask);
        }

        if (!stats.disableOutstandingHists && needsResponse) {
            ++stats.outstandingWriteReqs;
        }

        if (!stats.disableITTDists) {
            // Sample value of write-to-write inter transaction time
            if (stats.timeOfLastWrite != 0) {
                stats.ittWriteWrite.sample(curTick() - stats.timeOfLastWrite);
            }
            stats.timeOfLastWrite = curTick();

            // Sample value of req-to-req inter transaction time
            if (stats.timeOfLastReq != 0) {
                stats.ittReqReq.sample(curTick() - stats.timeOfLastReq);
            }
            stats.timeOfLastReq = curTick();
        }
    } else if (successful) {
        DPRINTF(CommMonitor, "Forwarded non read/write request\n");
    }

    return successful;
}

bool
CommMonitor::recvTimingResp(PacketPtr pkt)
{
    // should always see responses
    assert(pkt->isResponse());

    // Store relevant fields of packet, because packet may be modified
    // or even deleted when sendTiming() is called.
    bool isRead = pkt->isRead();
    bool isWrite = pkt->isWrite();
    unsigned size = pkt->getSize();
    Tick latency = 0;
    CommMonitorSenderState* commReceivedState =
        dynamic_cast<CommMonitorSenderState*>(pkt->senderState);

    if (!stats.disableLatencyHists) {
        // Restore initial sender state
        if (commReceivedState == NULL)
            panic("Monitor got a response without monitor sender state\n");

        // Restore the sate
        pkt->senderState = commReceivedState->origSenderState;
    }

    // Attempt to send the packet
    bool successful = slavePort.sendTimingResp(pkt);

    if (!stats.disableLatencyHists) {
        // If packet successfully send, sample value of latency,
        // afterwards delete sender state, otherwise restore state
        if (successful) {
            latency = curTick() - commReceivedState->transmitTime;
            DPRINTF(CommMonitor, "Latency: %d\n", latency);
            delete commReceivedState;
        } else {
            // Don't delete anything and let the packet look like we
            // did not touch it
            pkt->senderState = commReceivedState;
        }
    }

    if (successful && isRead) {
        // Decrement number of outstanding read requests
        DPRINTF(CommMonitor, "Received read response\n");
        if (!stats.disableOutstandingHists) {
            assert(stats.outstandingReadReqs != 0);
            --stats.outstandingReadReqs;
        }

        if (!stats.disableLatencyHists) {
            stats.readLatencyHist.sample(latency);
        }

        // Update the bandwidth stats based on responses for reads
        if (!stats.disableBandwidthHists) {
            stats.readBytes += size;
            stats.totalReadBytes += size;
        }

    } else if (successful && isWrite) {
        // Decrement number of outstanding write requests
        DPRINTF(CommMonitor, "Received write response\n");
        if (!stats.disableOutstandingHists) {
            assert(stats.outstandingWriteReqs != 0);
            --stats.outstandingWriteReqs;
        }

        if (!stats.disableLatencyHists) {
            stats.writeLatencyHist.sample(latency);
        }
    } else if (successful) {
        DPRINTF(CommMonitor, "Received non read/write response\n");
    }
    return successful;
}

void
CommMonitor::recvTimingSnoopReq(PacketPtr pkt)
{
    slavePort.sendTimingSnoopReq(pkt);
}

bool
CommMonitor::recvTimingSnoopResp(PacketPtr pkt)
{
    return masterPort.sendTimingSnoopResp(pkt);
}

bool
CommMonitor::isSnooping() const
{
    // check if the connected master port is snooping
    return slavePort.isSnooping();
}

unsigned
CommMonitor::deviceBlockSizeMaster()
{
    return slavePort.peerBlockSize();
}

unsigned
CommMonitor::deviceBlockSizeSlave()
{
    return masterPort.peerBlockSize();
}

AddrRangeList
CommMonitor::getAddrRanges() const
{
    // get the address ranges of the connected slave port
    return masterPort.getAddrRanges();
}

void
CommMonitor::recvRetryMaster()
{
    slavePort.sendRetry();
}

void
CommMonitor::recvRetrySlave()
{
    masterPort.sendRetry();
}

void
CommMonitor::recvRangeChange()
{
    slavePort.sendRangeChange();
}

void
CommMonitor::regStats()
{
    // Initialise all the monitor stats
    using namespace Stats;

    stats.readBurstLengthHist
        .init(params()->burst_length_bins)
        .name(name() + ".readBurstLengthHist")
        .desc("Histogram of burst lengths of transmitted packets")
        .flags(stats.disableBurstLengthHists ? nozero : pdf);

    stats.writeBurstLengthHist
        .init(params()->burst_length_bins)
        .name(name() + ".writeBurstLengthHist")
        .desc("Histogram of burst lengths of transmitted packets")
        .flags(stats.disableBurstLengthHists ? nozero : pdf);

    // Stats based on received responses
    stats.readBandwidthHist
        .init(params()->bandwidth_bins)
        .name(name() + ".readBandwidthHist")
        .desc("Histogram of read bandwidth per sample period (bytes/s)")
        .flags(stats.disableBandwidthHists ? nozero : pdf);

    stats.averageReadBW
        .name(name() + ".averageReadBandwidth")
        .desc("Average read bandwidth (bytes/s)")
        .flags(stats.disableBandwidthHists ? nozero : pdf);

    stats.totalReadBytes
        .name(name() + ".totalReadBytes")
        .desc("Number of bytes read")
        .flags(stats.disableBandwidthHists ? nozero : pdf);

    stats.averageReadBW = stats.totalReadBytes / simSeconds;

    // Stats based on successfully sent requests
    stats.writeBandwidthHist
        .init(params()->bandwidth_bins)
        .name(name() + ".writeBandwidthHist")
        .desc("Histogram of write bandwidth (bytes/s)")
        .flags(stats.disableBandwidthHists ? (pdf | nozero) : pdf);

    stats.averageWriteBW
        .name(name() + ".averageWriteBandwidth")
        .desc("Average write bandwidth (bytes/s)")
        .flags(stats.disableBandwidthHists ? nozero : pdf);

    stats.totalWrittenBytes
        .name(name() + ".totalWrittenBytes")
        .desc("Number of bytes written")
        .flags(stats.disableBandwidthHists ? nozero : pdf);

    stats.averageWriteBW = stats.totalWrittenBytes / simSeconds;

    stats.readLatencyHist
        .init(params()->latency_bins)
        .name(name() + ".readLatencyHist")
        .desc("Read request-response latency")
        .flags(stats.disableLatencyHists ? nozero : pdf);

    stats.writeLatencyHist
        .init(params()->latency_bins)
        .name(name() + ".writeLatencyHist")
        .desc("Write request-response latency")
        .flags(stats.disableLatencyHists ? nozero : pdf);

    stats.ittReadRead
        .init(1, params()->itt_max_bin, params()->itt_max_bin /
              params()->itt_bins)
        .name(name() + ".ittReadRead")
        .desc("Read-to-read inter transaction time")
        .flags(stats.disableITTDists ? nozero : pdf);

    stats.ittWriteWrite
        .init(1, params()->itt_max_bin, params()->itt_max_bin /
              params()->itt_bins)
        .name(name() + ".ittWriteWrite")
        .desc("Write-to-write inter transaction time")
        .flags(stats.disableITTDists ? nozero : pdf);

    stats.ittReqReq
        .init(1, params()->itt_max_bin, params()->itt_max_bin /
              params()->itt_bins)
        .name(name() + ".ittReqReq")
        .desc("Request-to-request inter transaction time")
        .flags(stats.disableITTDists ? nozero : pdf);

    stats.outstandingReadsHist
        .init(params()->outstanding_bins)
        .name(name() + ".outstandingReadsHist")
        .desc("Outstanding read transactions")
        .flags(stats.disableOutstandingHists ? nozero : pdf);

    stats.outstandingWritesHist
        .init(params()->outstanding_bins)
        .name(name() + ".outstandingWritesHist")
        .desc("Outstanding write transactions")
        .flags(stats.disableOutstandingHists ? nozero : pdf);

    stats.readTransHist
        .init(params()->transaction_bins)
        .name(name() + ".readTransHist")
        .desc("Histogram of read transactions per sample period")
        .flags(stats.disableTransactionHists ? nozero : pdf);

    stats.writeTransHist
        .init(params()->transaction_bins)
        .name(name() + ".writeTransHist")
        .desc("Histogram of read transactions per sample period")
        .flags(stats.disableTransactionHists ? nozero : pdf);

    stats.readAddrDist
        .init(0)
        .name(name() + ".readAddrDist")
        .desc("Read address distribution")
        .flags(stats.disableAddrDists ? nozero : pdf);

    stats.writeAddrDist
        .init(0)
        .name(name() + ".writeAddrDist")
        .desc("Write address distribution")
        .flags(stats.disableAddrDists ? nozero : pdf);
}

void
CommMonitor::samplePeriodic()
{
    // the periodic stats update runs on the granularity of sample
    // periods, but in combination with this there may also be a
    // external resets and dumps of the stats (through schedStatEvent)
    // causing the stats themselves to capture less than a sample
    // period

    // only capture if we have not reset the stats during the last
    // sample period
    if (simTicks.value() >= samplePeriodTicks) {
        if (!stats.disableTransactionHists) {
            stats.readTransHist.sample(stats.readTrans);
            stats.writeTransHist.sample(stats.writeTrans);
        }

        if (!stats.disableBandwidthHists) {
            stats.readBandwidthHist.sample(stats.readBytes / samplePeriod);
            stats.writeBandwidthHist.sample(stats.writtenBytes / samplePeriod);
        }

        if (!stats.disableOutstandingHists) {
            stats.outstandingReadsHist.sample(stats.outstandingReadReqs);
            stats.outstandingWritesHist.sample(stats.outstandingWriteReqs);
        }
    }

    // reset the sampled values
    stats.readTrans = 0;
    stats.writeTrans = 0;

    stats.readBytes = 0;
    stats.writtenBytes = 0;

    schedule(samplePeriodicEvent, curTick() + samplePeriodTicks);
}

void
CommMonitor::startup()
{
    schedule(samplePeriodicEvent, curTick() + samplePeriodTicks);
}