comm_monitor.cc revision 11804
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#include "mem/comm_monitor.hh" 44 45#include "base/trace.hh" 46#include "debug/CommMonitor.hh" 47#include "sim/stats.hh" 48 49CommMonitor::CommMonitor(Params* params) 50 : MemObject(params), 51 masterPort(name() + "-master", *this), 52 slavePort(name() + "-slave", *this), 53 samplePeriodicEvent(this), 54 samplePeriodTicks(params->sample_period), 55 samplePeriod(params->sample_period / SimClock::Float::s), 56 stats(params) 57{ 58 DPRINTF(CommMonitor, 59 "Created monitor %s with sample period %d ticks (%f ms)\n", 60 name(), samplePeriodTicks, samplePeriod * 1E3); 61} 62 63CommMonitor* 64CommMonitorParams::create() 65{ 66 return new CommMonitor(this); 67} 68 69void 70CommMonitor::init() 71{ 72 // make sure both sides of the monitor are connected 73 if (!slavePort.isConnected() || !masterPort.isConnected()) 74 fatal("Communication monitor is not connected on both sides.\n"); 75} 76 77void 78CommMonitor::regProbePoints() 79{ 80 ppPktReq.reset(new ProbePoints::Packet(getProbeManager(), "PktRequest")); 81 ppPktResp.reset(new ProbePoints::Packet(getProbeManager(), "PktResponse")); 82} 83 84BaseMasterPort& 85CommMonitor::getMasterPort(const std::string& if_name, PortID idx) 86{ 87 if (if_name == "master") { 88 return masterPort; 89 } else { 90 return MemObject::getMasterPort(if_name, idx); 91 } 92} 93 94BaseSlavePort& 95CommMonitor::getSlavePort(const std::string& if_name, PortID idx) 96{ 97 if (if_name == "slave") { 98 return slavePort; 99 } else { 100 return MemObject::getSlavePort(if_name, idx); 101 } 102} 103 104void 105CommMonitor::recvFunctional(PacketPtr pkt) 106{ 107 masterPort.sendFunctional(pkt); 108} 109 110void 111CommMonitor::recvFunctionalSnoop(PacketPtr pkt) 112{ 113 slavePort.sendFunctionalSnoop(pkt); 114} 115 116void 117CommMonitor::MonitorStats::updateReqStats( 118 const ProbePoints::PacketInfo& pkt_info, bool is_atomic, 119 bool expects_response) 120{ 121 if (pkt_info.cmd.isRead()) { 122 // Increment number of observed read transactions 123 if (!disableTransactionHists) 124 ++readTrans; 125 126 // Get sample of burst length 127 if (!disableBurstLengthHists) 128 readBurstLengthHist.sample(pkt_info.size); 129 130 // Sample the masked address 131 if (!disableAddrDists) 132 readAddrDist.sample(pkt_info.addr & readAddrMask); 133 134 if (!disableITTDists) { 135 // Sample value of read-read inter transaction time 136 if (timeOfLastRead != 0) 137 ittReadRead.sample(curTick() - timeOfLastRead); 138 timeOfLastRead = curTick(); 139 140 // Sample value of req-req inter transaction time 141 if (timeOfLastReq != 0) 142 ittReqReq.sample(curTick() - timeOfLastReq); 143 timeOfLastReq = curTick(); 144 } 145 if (!is_atomic && !disableOutstandingHists && expects_response) 146 ++outstandingReadReqs; 147 148 } else if (pkt_info.cmd.isWrite()) { 149 // Same as for reads 150 if (!disableTransactionHists) 151 ++writeTrans; 152 153 if (!disableBurstLengthHists) 154 writeBurstLengthHist.sample(pkt_info.size); 155 156 // Update the bandwidth stats on the request 157 if (!disableBandwidthHists) { 158 writtenBytes += pkt_info.size; 159 totalWrittenBytes += pkt_info.size; 160 } 161 162 // Sample the masked write address 163 if (!disableAddrDists) 164 writeAddrDist.sample(pkt_info.addr & writeAddrMask); 165 166 if (!disableITTDists) { 167 // Sample value of write-to-write inter transaction time 168 if (timeOfLastWrite != 0) 169 ittWriteWrite.sample(curTick() - timeOfLastWrite); 170 timeOfLastWrite = curTick(); 171 172 // Sample value of req-to-req inter transaction time 173 if (timeOfLastReq != 0) 174 ittReqReq.sample(curTick() - timeOfLastReq); 175 timeOfLastReq = curTick(); 176 } 177 178 if (!is_atomic && !disableOutstandingHists && expects_response) 179 ++outstandingWriteReqs; 180 } 181} 182 183void 184CommMonitor::MonitorStats::updateRespStats( 185 const ProbePoints::PacketInfo& pkt_info, Tick latency, bool is_atomic) 186{ 187 if (pkt_info.cmd.isRead()) { 188 // Decrement number of outstanding read requests 189 if (!is_atomic && !disableOutstandingHists) { 190 assert(outstandingReadReqs != 0); 191 --outstandingReadReqs; 192 } 193 194 if (!disableLatencyHists) 195 readLatencyHist.sample(latency); 196 197 // Update the bandwidth stats based on responses for reads 198 if (!disableBandwidthHists) { 199 readBytes += pkt_info.size; 200 totalReadBytes += pkt_info.size; 201 } 202 203 } else if (pkt_info.cmd.isWrite()) { 204 // Decrement number of outstanding write requests 205 if (!is_atomic && !disableOutstandingHists) { 206 assert(outstandingWriteReqs != 0); 207 --outstandingWriteReqs; 208 } 209 210 if (!disableLatencyHists) 211 writeLatencyHist.sample(latency); 212 } 213} 214 215Tick 216CommMonitor::recvAtomic(PacketPtr pkt) 217{ 218 const bool expects_response(pkt->needsResponse() && 219 !pkt->cacheResponding()); 220 ProbePoints::PacketInfo req_pkt_info(pkt); 221 ppPktReq->notify(req_pkt_info); 222 223 const Tick delay(masterPort.sendAtomic(pkt)); 224 225 stats.updateReqStats(req_pkt_info, true, expects_response); 226 if (expects_response) 227 stats.updateRespStats(req_pkt_info, delay, true); 228 229 assert(pkt->isResponse()); 230 ProbePoints::PacketInfo resp_pkt_info(pkt); 231 ppPktResp->notify(resp_pkt_info); 232 return delay; 233} 234 235Tick 236CommMonitor::recvAtomicSnoop(PacketPtr pkt) 237{ 238 return slavePort.sendAtomicSnoop(pkt); 239} 240 241bool 242CommMonitor::recvTimingReq(PacketPtr pkt) 243{ 244 // should always see a request 245 assert(pkt->isRequest()); 246 247 // Store relevant fields of packet, because packet may be modified 248 // or even deleted when sendTiming() is called. 249 const ProbePoints::PacketInfo pkt_info(pkt); 250 251 const bool is_read = pkt->isRead(); 252 const bool is_write = pkt->isWrite(); 253 const bool expects_response(pkt->needsResponse() && 254 !pkt->cacheResponding()); 255 256 // If a cache miss is served by a cache, a monitor near the memory 257 // would see a request which needs a response, but this response 258 // would not come back from the memory. Therefore we additionally 259 // have to check the cacheResponding flag 260 if (expects_response && !stats.disableLatencyHists) { 261 pkt->pushSenderState(new CommMonitorSenderState(curTick())); 262 } 263 264 // Attempt to send the packet 265 bool successful = masterPort.sendTimingReq(pkt); 266 267 // If not successful, restore the sender state 268 if (!successful && expects_response && !stats.disableLatencyHists) { 269 delete pkt->popSenderState(); 270 } 271 272 if (successful) { 273 ppPktReq->notify(pkt_info); 274 } 275 276 if (successful) { 277 DPRINTF(CommMonitor, "Forwarded %s request\n", 278 (is_read ? "read" : (is_write ? "write" : "non read/write"))); 279 stats.updateReqStats(pkt_info, false, expects_response); 280 } 281 return successful; 282} 283 284bool 285CommMonitor::recvTimingResp(PacketPtr pkt) 286{ 287 // should always see responses 288 assert(pkt->isResponse()); 289 290 // Store relevant fields of packet, because packet may be modified 291 // or even deleted when sendTiming() is called. 292 const ProbePoints::PacketInfo pkt_info(pkt); 293 294 bool is_read = pkt->isRead(); 295 bool is_write = pkt->isWrite(); 296 Tick latency = 0; 297 CommMonitorSenderState* received_state = 298 dynamic_cast<CommMonitorSenderState*>(pkt->senderState); 299 300 if (!stats.disableLatencyHists) { 301 // Restore initial sender state 302 if (received_state == NULL) 303 panic("Monitor got a response without monitor sender state\n"); 304 305 // Restore the sate 306 pkt->senderState = received_state->predecessor; 307 } 308 309 // Attempt to send the packet 310 bool successful = slavePort.sendTimingResp(pkt); 311 312 if (!stats.disableLatencyHists) { 313 // If packet successfully send, sample value of latency, 314 // afterwards delete sender state, otherwise restore state 315 if (successful) { 316 latency = curTick() - received_state->transmitTime; 317 DPRINTF(CommMonitor, "Latency: %d\n", latency); 318 delete received_state; 319 } else { 320 // Don't delete anything and let the packet look like we 321 // did not touch it 322 pkt->senderState = received_state; 323 } 324 } 325 326 if (successful) { 327 ppPktResp->notify(pkt_info); 328 DPRINTF(CommMonitor, "Received %s response\n", 329 (is_read ? "Read" : (is_write ? "Write" : "non read/write"))); 330 stats.updateRespStats(pkt_info, latency, false); 331 } 332 return successful; 333} 334 335void 336CommMonitor::recvTimingSnoopReq(PacketPtr pkt) 337{ 338 slavePort.sendTimingSnoopReq(pkt); 339} 340 341bool 342CommMonitor::recvTimingSnoopResp(PacketPtr pkt) 343{ 344 return masterPort.sendTimingSnoopResp(pkt); 345} 346 347void 348CommMonitor::recvRetrySnoopResp() 349{ 350 slavePort.sendRetrySnoopResp(); 351} 352 353bool 354CommMonitor::isSnooping() const 355{ 356 // check if the connected master port is snooping 357 return slavePort.isSnooping(); 358} 359 360AddrRangeList 361CommMonitor::getAddrRanges() const 362{ 363 // get the address ranges of the connected slave port 364 return masterPort.getAddrRanges(); 365} 366 367void 368CommMonitor::recvReqRetry() 369{ 370 slavePort.sendRetryReq(); 371} 372 373void 374CommMonitor::recvRespRetry() 375{ 376 masterPort.sendRetryResp(); 377} 378 379void 380CommMonitor::recvRangeChange() 381{ 382 slavePort.sendRangeChange(); 383} 384 385void 386CommMonitor::regStats() 387{ 388 MemObject::regStats(); 389 390 // Initialise all the monitor stats 391 using namespace Stats; 392 393 stats.readBurstLengthHist 394 .init(params()->burst_length_bins) 395 .name(name() + ".readBurstLengthHist") 396 .desc("Histogram of burst lengths of transmitted packets") 397 .flags(stats.disableBurstLengthHists ? nozero : pdf); 398 399 stats.writeBurstLengthHist 400 .init(params()->burst_length_bins) 401 .name(name() + ".writeBurstLengthHist") 402 .desc("Histogram of burst lengths of transmitted packets") 403 .flags(stats.disableBurstLengthHists ? nozero : pdf); 404 405 // Stats based on received responses 406 stats.readBandwidthHist 407 .init(params()->bandwidth_bins) 408 .name(name() + ".readBandwidthHist") 409 .desc("Histogram of read bandwidth per sample period (bytes/s)") 410 .flags(stats.disableBandwidthHists ? nozero : pdf); 411 412 stats.averageReadBW 413 .name(name() + ".averageReadBandwidth") 414 .desc("Average read bandwidth (bytes/s)") 415 .flags(stats.disableBandwidthHists ? nozero : pdf); 416 417 stats.totalReadBytes 418 .name(name() + ".totalReadBytes") 419 .desc("Number of bytes read") 420 .flags(stats.disableBandwidthHists ? nozero : pdf); 421 422 stats.averageReadBW = stats.totalReadBytes / simSeconds; 423 424 // Stats based on successfully sent requests 425 stats.writeBandwidthHist 426 .init(params()->bandwidth_bins) 427 .name(name() + ".writeBandwidthHist") 428 .desc("Histogram of write bandwidth (bytes/s)") 429 .flags(stats.disableBandwidthHists ? (pdf | nozero) : pdf); 430 431 stats.averageWriteBW 432 .name(name() + ".averageWriteBandwidth") 433 .desc("Average write bandwidth (bytes/s)") 434 .flags(stats.disableBandwidthHists ? nozero : pdf); 435 436 stats.totalWrittenBytes 437 .name(name() + ".totalWrittenBytes") 438 .desc("Number of bytes written") 439 .flags(stats.disableBandwidthHists ? nozero : pdf); 440 441 stats.averageWriteBW = stats.totalWrittenBytes / simSeconds; 442 443 stats.readLatencyHist 444 .init(params()->latency_bins) 445 .name(name() + ".readLatencyHist") 446 .desc("Read request-response latency") 447 .flags(stats.disableLatencyHists ? nozero : pdf); 448 449 stats.writeLatencyHist 450 .init(params()->latency_bins) 451 .name(name() + ".writeLatencyHist") 452 .desc("Write request-response latency") 453 .flags(stats.disableLatencyHists ? nozero : pdf); 454 455 stats.ittReadRead 456 .init(1, params()->itt_max_bin, params()->itt_max_bin / 457 params()->itt_bins) 458 .name(name() + ".ittReadRead") 459 .desc("Read-to-read inter transaction time") 460 .flags(stats.disableITTDists ? nozero : pdf); 461 462 stats.ittWriteWrite 463 .init(1, params()->itt_max_bin, params()->itt_max_bin / 464 params()->itt_bins) 465 .name(name() + ".ittWriteWrite") 466 .desc("Write-to-write inter transaction time") 467 .flags(stats.disableITTDists ? nozero : pdf); 468 469 stats.ittReqReq 470 .init(1, params()->itt_max_bin, params()->itt_max_bin / 471 params()->itt_bins) 472 .name(name() + ".ittReqReq") 473 .desc("Request-to-request inter transaction time") 474 .flags(stats.disableITTDists ? nozero : pdf); 475 476 stats.outstandingReadsHist 477 .init(params()->outstanding_bins) 478 .name(name() + ".outstandingReadsHist") 479 .desc("Outstanding read transactions") 480 .flags(stats.disableOutstandingHists ? nozero : pdf); 481 482 stats.outstandingWritesHist 483 .init(params()->outstanding_bins) 484 .name(name() + ".outstandingWritesHist") 485 .desc("Outstanding write transactions") 486 .flags(stats.disableOutstandingHists ? nozero : pdf); 487 488 stats.readTransHist 489 .init(params()->transaction_bins) 490 .name(name() + ".readTransHist") 491 .desc("Histogram of read transactions per sample period") 492 .flags(stats.disableTransactionHists ? nozero : pdf); 493 494 stats.writeTransHist 495 .init(params()->transaction_bins) 496 .name(name() + ".writeTransHist") 497 .desc("Histogram of read transactions per sample period") 498 .flags(stats.disableTransactionHists ? nozero : pdf); 499 500 stats.readAddrDist 501 .init(0) 502 .name(name() + ".readAddrDist") 503 .desc("Read address distribution") 504 .flags(stats.disableAddrDists ? nozero : pdf); 505 506 stats.writeAddrDist 507 .init(0) 508 .name(name() + ".writeAddrDist") 509 .desc("Write address distribution") 510 .flags(stats.disableAddrDists ? nozero : pdf); 511} 512 513void 514CommMonitor::samplePeriodic() 515{ 516 // the periodic stats update runs on the granularity of sample 517 // periods, but in combination with this there may also be a 518 // external resets and dumps of the stats (through schedStatEvent) 519 // causing the stats themselves to capture less than a sample 520 // period 521 522 // only capture if we have not reset the stats during the last 523 // sample period 524 if (simTicks.value() >= samplePeriodTicks) { 525 if (!stats.disableTransactionHists) { 526 stats.readTransHist.sample(stats.readTrans); 527 stats.writeTransHist.sample(stats.writeTrans); 528 } 529 530 if (!stats.disableBandwidthHists) { 531 stats.readBandwidthHist.sample(stats.readBytes / samplePeriod); 532 stats.writeBandwidthHist.sample(stats.writtenBytes / samplePeriod); 533 } 534 535 if (!stats.disableOutstandingHists) { 536 stats.outstandingReadsHist.sample(stats.outstandingReadReqs); 537 stats.outstandingWritesHist.sample(stats.outstandingWriteReqs); 538 } 539 } 540 541 // reset the sampled values 542 stats.readTrans = 0; 543 stats.writeTrans = 0; 544 545 stats.readBytes = 0; 546 stats.writtenBytes = 0; 547 548 schedule(samplePeriodicEvent, curTick() + samplePeriodTicks); 549} 550 551void 552CommMonitor::startup() 553{ 554 schedule(samplePeriodicEvent, curTick() + samplePeriodTicks); 555} 556