lsq_unit_impl.hh revision 3731:4cd483eb6f16
1/* 2 * Copyright (c) 2004-2005 The Regents of The University of Michigan 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are 7 * met: redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer; 9 * redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution; 12 * neither the name of the copyright holders nor the names of its 13 * contributors may be used to endorse or promote products derived from 14 * this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 * 28 * Authors: Kevin Lim 29 * Korey Sewell 30 */ 31 32#include "arch/locked_mem.hh" 33#include "config/use_checker.hh" 34 35#include "cpu/o3/lsq.hh" 36#include "cpu/o3/lsq_unit.hh" 37#include "base/str.hh" 38#include "mem/packet.hh" 39#include "mem/request.hh" 40 41#if USE_CHECKER 42#include "cpu/checker/cpu.hh" 43#endif 44 45template<class Impl> 46LSQUnit<Impl>::WritebackEvent::WritebackEvent(DynInstPtr &_inst, PacketPtr _pkt, 47 LSQUnit *lsq_ptr) 48 : Event(&mainEventQueue), inst(_inst), pkt(_pkt), lsqPtr(lsq_ptr) 49{ 50 this->setFlags(Event::AutoDelete); 51} 52 53template<class Impl> 54void 55LSQUnit<Impl>::WritebackEvent::process() 56{ 57 if (!lsqPtr->isSwitchedOut()) { 58 lsqPtr->writeback(inst, pkt); 59 } 60 delete pkt; 61} 62 63template<class Impl> 64const char * 65LSQUnit<Impl>::WritebackEvent::description() 66{ 67 return "Store writeback event"; 68} 69 70template<class Impl> 71void 72LSQUnit<Impl>::completeDataAccess(PacketPtr pkt) 73{ 74 LSQSenderState *state = dynamic_cast<LSQSenderState *>(pkt->senderState); 75 DynInstPtr inst = state->inst; 76 DPRINTF(IEW, "Writeback event [sn:%lli]\n", inst->seqNum); 77 DPRINTF(Activity, "Activity: Writeback event [sn:%lli]\n", inst->seqNum); 78 79 //iewStage->ldstQueue.removeMSHR(inst->threadNumber,inst->seqNum); 80 81 if (isSwitchedOut() || inst->isSquashed()) { 82 iewStage->decrWb(inst->seqNum); 83 delete state; 84 delete pkt; 85 return; 86 } else { 87 if (!state->noWB) { 88 writeback(inst, pkt); 89 } 90 91 if (inst->isStore()) { 92 completeStore(state->idx); 93 } 94 } 95 96 delete state; 97 delete pkt; 98} 99 100template <class Impl> 101LSQUnit<Impl>::LSQUnit() 102 : loads(0), stores(0), storesToWB(0), stalled(false), 103 isStoreBlocked(false), isLoadBlocked(false), 104 loadBlockedHandled(false) 105{ 106} 107 108template<class Impl> 109void 110LSQUnit<Impl>::init(Params *params, LSQ *lsq_ptr, unsigned maxLQEntries, 111 unsigned maxSQEntries, unsigned id) 112{ 113 DPRINTF(LSQUnit, "Creating LSQUnit%i object.\n",id); 114 115 switchedOut = false; 116 117 lsq = lsq_ptr; 118 119 lsqID = id; 120 121 // Add 1 for the sentinel entry (they are circular queues). 122 LQEntries = maxLQEntries + 1; 123 SQEntries = maxSQEntries + 1; 124 125 loadQueue.resize(LQEntries); 126 storeQueue.resize(SQEntries); 127 128 loadHead = loadTail = 0; 129 130 storeHead = storeWBIdx = storeTail = 0; 131 132 usedPorts = 0; 133 cachePorts = params->cachePorts; 134 135 retryPkt = NULL; 136 memDepViolator = NULL; 137 138 blockedLoadSeqNum = 0; 139} 140 141template<class Impl> 142void 143LSQUnit<Impl>::setCPU(O3CPU *cpu_ptr) 144{ 145 cpu = cpu_ptr; 146 147#if USE_CHECKER 148 if (cpu->checker) { 149 cpu->checker->setDcachePort(dcachePort); 150 } 151#endif 152} 153 154template<class Impl> 155std::string 156LSQUnit<Impl>::name() const 157{ 158 if (Impl::MaxThreads == 1) { 159 return iewStage->name() + ".lsq"; 160 } else { 161 return iewStage->name() + ".lsq.thread." + to_string(lsqID); 162 } 163} 164 165template<class Impl> 166void 167LSQUnit<Impl>::regStats() 168{ 169 lsqForwLoads 170 .name(name() + ".forwLoads") 171 .desc("Number of loads that had data forwarded from stores"); 172 173 invAddrLoads 174 .name(name() + ".invAddrLoads") 175 .desc("Number of loads ignored due to an invalid address"); 176 177 lsqSquashedLoads 178 .name(name() + ".squashedLoads") 179 .desc("Number of loads squashed"); 180 181 lsqIgnoredResponses 182 .name(name() + ".ignoredResponses") 183 .desc("Number of memory responses ignored because the instruction is squashed"); 184 185 lsqMemOrderViolation 186 .name(name() + ".memOrderViolation") 187 .desc("Number of memory ordering violations"); 188 189 lsqSquashedStores 190 .name(name() + ".squashedStores") 191 .desc("Number of stores squashed"); 192 193 invAddrSwpfs 194 .name(name() + ".invAddrSwpfs") 195 .desc("Number of software prefetches ignored due to an invalid address"); 196 197 lsqBlockedLoads 198 .name(name() + ".blockedLoads") 199 .desc("Number of blocked loads due to partial load-store forwarding"); 200 201 lsqRescheduledLoads 202 .name(name() + ".rescheduledLoads") 203 .desc("Number of loads that were rescheduled"); 204 205 lsqCacheBlocked 206 .name(name() + ".cacheBlocked") 207 .desc("Number of times an access to memory failed due to the cache being blocked"); 208} 209 210template<class Impl> 211void 212LSQUnit<Impl>::clearLQ() 213{ 214 loadQueue.clear(); 215} 216 217template<class Impl> 218void 219LSQUnit<Impl>::clearSQ() 220{ 221 storeQueue.clear(); 222} 223 224template<class Impl> 225void 226LSQUnit<Impl>::switchOut() 227{ 228 switchedOut = true; 229 for (int i = 0; i < loadQueue.size(); ++i) { 230 assert(!loadQueue[i]); 231 loadQueue[i] = NULL; 232 } 233 234 assert(storesToWB == 0); 235} 236 237template<class Impl> 238void 239LSQUnit<Impl>::takeOverFrom() 240{ 241 switchedOut = false; 242 loads = stores = storesToWB = 0; 243 244 loadHead = loadTail = 0; 245 246 storeHead = storeWBIdx = storeTail = 0; 247 248 usedPorts = 0; 249 250 memDepViolator = NULL; 251 252 blockedLoadSeqNum = 0; 253 254 stalled = false; 255 isLoadBlocked = false; 256 loadBlockedHandled = false; 257} 258 259template<class Impl> 260void 261LSQUnit<Impl>::resizeLQ(unsigned size) 262{ 263 unsigned size_plus_sentinel = size + 1; 264 assert(size_plus_sentinel >= LQEntries); 265 266 if (size_plus_sentinel > LQEntries) { 267 while (size_plus_sentinel > loadQueue.size()) { 268 DynInstPtr dummy; 269 loadQueue.push_back(dummy); 270 LQEntries++; 271 } 272 } else { 273 LQEntries = size_plus_sentinel; 274 } 275 276} 277 278template<class Impl> 279void 280LSQUnit<Impl>::resizeSQ(unsigned size) 281{ 282 unsigned size_plus_sentinel = size + 1; 283 if (size_plus_sentinel > SQEntries) { 284 while (size_plus_sentinel > storeQueue.size()) { 285 SQEntry dummy; 286 storeQueue.push_back(dummy); 287 SQEntries++; 288 } 289 } else { 290 SQEntries = size_plus_sentinel; 291 } 292} 293 294template <class Impl> 295void 296LSQUnit<Impl>::insert(DynInstPtr &inst) 297{ 298 assert(inst->isMemRef()); 299 300 assert(inst->isLoad() || inst->isStore()); 301 302 if (inst->isLoad()) { 303 insertLoad(inst); 304 } else { 305 insertStore(inst); 306 } 307 308 inst->setInLSQ(); 309} 310 311template <class Impl> 312void 313LSQUnit<Impl>::insertLoad(DynInstPtr &load_inst) 314{ 315 assert((loadTail + 1) % LQEntries != loadHead); 316 assert(loads < LQEntries); 317 318 DPRINTF(LSQUnit, "Inserting load PC %#x, idx:%i [sn:%lli]\n", 319 load_inst->readPC(), loadTail, load_inst->seqNum); 320 321 load_inst->lqIdx = loadTail; 322 323 if (stores == 0) { 324 load_inst->sqIdx = -1; 325 } else { 326 load_inst->sqIdx = storeTail; 327 } 328 329 loadQueue[loadTail] = load_inst; 330 331 incrLdIdx(loadTail); 332 333 ++loads; 334} 335 336template <class Impl> 337void 338LSQUnit<Impl>::insertStore(DynInstPtr &store_inst) 339{ 340 // Make sure it is not full before inserting an instruction. 341 assert((storeTail + 1) % SQEntries != storeHead); 342 assert(stores < SQEntries); 343 344 DPRINTF(LSQUnit, "Inserting store PC %#x, idx:%i [sn:%lli]\n", 345 store_inst->readPC(), storeTail, store_inst->seqNum); 346 347 store_inst->sqIdx = storeTail; 348 store_inst->lqIdx = loadTail; 349 350 storeQueue[storeTail] = SQEntry(store_inst); 351 352 incrStIdx(storeTail); 353 354 ++stores; 355} 356 357template <class Impl> 358typename Impl::DynInstPtr 359LSQUnit<Impl>::getMemDepViolator() 360{ 361 DynInstPtr temp = memDepViolator; 362 363 memDepViolator = NULL; 364 365 return temp; 366} 367 368template <class Impl> 369unsigned 370LSQUnit<Impl>::numFreeEntries() 371{ 372 unsigned free_lq_entries = LQEntries - loads; 373 unsigned free_sq_entries = SQEntries - stores; 374 375 // Both the LQ and SQ entries have an extra dummy entry to differentiate 376 // empty/full conditions. Subtract 1 from the free entries. 377 if (free_lq_entries < free_sq_entries) { 378 return free_lq_entries - 1; 379 } else { 380 return free_sq_entries - 1; 381 } 382} 383 384template <class Impl> 385int 386LSQUnit<Impl>::numLoadsReady() 387{ 388 int load_idx = loadHead; 389 int retval = 0; 390 391 while (load_idx != loadTail) { 392 assert(loadQueue[load_idx]); 393 394 if (loadQueue[load_idx]->readyToIssue()) { 395 ++retval; 396 } 397 } 398 399 return retval; 400} 401 402template <class Impl> 403Fault 404LSQUnit<Impl>::executeLoad(DynInstPtr &inst) 405{ 406 // Execute a specific load. 407 Fault load_fault = NoFault; 408 409 DPRINTF(LSQUnit, "Executing load PC %#x, [sn:%lli]\n", 410 inst->readPC(),inst->seqNum); 411 412 load_fault = inst->initiateAcc(); 413 414 // If the instruction faulted, then we need to send it along to commit 415 // without the instruction completing. 416 if (load_fault != NoFault) { 417 // Send this instruction to commit, also make sure iew stage 418 // realizes there is activity. 419 // Mark it as executed unless it is an uncached load that 420 // needs to hit the head of commit. 421 if (!(inst->req && inst->req->isUncacheable()) || 422 inst->isAtCommit()) { 423 inst->setExecuted(); 424 } 425 iewStage->instToCommit(inst); 426 iewStage->activityThisCycle(); 427 } 428 429 return load_fault; 430} 431 432template <class Impl> 433Fault 434LSQUnit<Impl>::executeStore(DynInstPtr &store_inst) 435{ 436 using namespace TheISA; 437 // Make sure that a store exists. 438 assert(stores != 0); 439 440 int store_idx = store_inst->sqIdx; 441 442 DPRINTF(LSQUnit, "Executing store PC %#x [sn:%lli]\n", 443 store_inst->readPC(), store_inst->seqNum); 444 445 // Check the recently completed loads to see if any match this store's 446 // address. If so, then we have a memory ordering violation. 447 int load_idx = store_inst->lqIdx; 448 449 Fault store_fault = store_inst->initiateAcc(); 450 451 if (storeQueue[store_idx].size == 0) { 452 DPRINTF(LSQUnit,"Fault on Store PC %#x, [sn:%lli],Size = 0\n", 453 store_inst->readPC(),store_inst->seqNum); 454 455 return store_fault; 456 } 457 458 assert(store_fault == NoFault); 459 460 if (store_inst->isStoreConditional()) { 461 // Store conditionals need to set themselves as able to 462 // writeback if we haven't had a fault by here. 463 storeQueue[store_idx].canWB = true; 464 465 ++storesToWB; 466 } 467 468 if (!memDepViolator) { 469 while (load_idx != loadTail) { 470 // Really only need to check loads that have actually executed 471 // It's safe to check all loads because effAddr is set to 472 // InvalAddr when the dyn inst is created. 473 474 // @todo: For now this is extra conservative, detecting a 475 // violation if the addresses match assuming all accesses 476 // are quad word accesses. 477 478 // @todo: Fix this, magic number being used here 479 if ((loadQueue[load_idx]->effAddr >> 8) == 480 (store_inst->effAddr >> 8)) { 481 // A load incorrectly passed this store. Squash and refetch. 482 // For now return a fault to show that it was unsuccessful. 483 memDepViolator = loadQueue[load_idx]; 484 ++lsqMemOrderViolation; 485 486 return genMachineCheckFault(); 487 } 488 489 incrLdIdx(load_idx); 490 } 491 492 // If we've reached this point, there was no violation. 493 memDepViolator = NULL; 494 } 495 496 return store_fault; 497} 498 499template <class Impl> 500void 501LSQUnit<Impl>::commitLoad() 502{ 503 assert(loadQueue[loadHead]); 504 505 DPRINTF(LSQUnit, "Committing head load instruction, PC %#x\n", 506 loadQueue[loadHead]->readPC()); 507 508 loadQueue[loadHead] = NULL; 509 510 incrLdIdx(loadHead); 511 512 --loads; 513} 514 515template <class Impl> 516void 517LSQUnit<Impl>::commitLoads(InstSeqNum &youngest_inst) 518{ 519 assert(loads == 0 || loadQueue[loadHead]); 520 521 while (loads != 0 && loadQueue[loadHead]->seqNum <= youngest_inst) { 522 commitLoad(); 523 } 524} 525 526template <class Impl> 527void 528LSQUnit<Impl>::commitStores(InstSeqNum &youngest_inst) 529{ 530 assert(stores == 0 || storeQueue[storeHead].inst); 531 532 int store_idx = storeHead; 533 534 while (store_idx != storeTail) { 535 assert(storeQueue[store_idx].inst); 536 // Mark any stores that are now committed and have not yet 537 // been marked as able to write back. 538 if (!storeQueue[store_idx].canWB) { 539 if (storeQueue[store_idx].inst->seqNum > youngest_inst) { 540 break; 541 } 542 DPRINTF(LSQUnit, "Marking store as able to write back, PC " 543 "%#x [sn:%lli]\n", 544 storeQueue[store_idx].inst->readPC(), 545 storeQueue[store_idx].inst->seqNum); 546 547 storeQueue[store_idx].canWB = true; 548 549 ++storesToWB; 550 } 551 552 incrStIdx(store_idx); 553 } 554} 555 556template <class Impl> 557void 558LSQUnit<Impl>::writebackStores() 559{ 560 while (storesToWB > 0 && 561 storeWBIdx != storeTail && 562 storeQueue[storeWBIdx].inst && 563 storeQueue[storeWBIdx].canWB && 564 usedPorts < cachePorts) { 565 566 if (isStoreBlocked || lsq->cacheBlocked()) { 567 DPRINTF(LSQUnit, "Unable to write back any more stores, cache" 568 " is blocked!\n"); 569 break; 570 } 571 572 // Store didn't write any data so no need to write it back to 573 // memory. 574 if (storeQueue[storeWBIdx].size == 0) { 575 completeStore(storeWBIdx); 576 577 incrStIdx(storeWBIdx); 578 579 continue; 580 } 581 582 ++usedPorts; 583 584 if (storeQueue[storeWBIdx].inst->isDataPrefetch()) { 585 incrStIdx(storeWBIdx); 586 587 continue; 588 } 589 590 assert(storeQueue[storeWBIdx].req); 591 assert(!storeQueue[storeWBIdx].committed); 592 593 DynInstPtr inst = storeQueue[storeWBIdx].inst; 594 595 Request *req = storeQueue[storeWBIdx].req; 596 storeQueue[storeWBIdx].committed = true; 597 598 assert(!inst->memData); 599 inst->memData = new uint8_t[64]; 600 memcpy(inst->memData, (uint8_t *)&storeQueue[storeWBIdx].data, 601 req->getSize()); 602 603 PacketPtr data_pkt = new Packet(req, Packet::WriteReq, Packet::Broadcast); 604 data_pkt->dataStatic(inst->memData); 605 606 LSQSenderState *state = new LSQSenderState; 607 state->isLoad = false; 608 state->idx = storeWBIdx; 609 state->inst = inst; 610 data_pkt->senderState = state; 611 612 DPRINTF(LSQUnit, "D-Cache: Writing back store idx:%i PC:%#x " 613 "to Addr:%#x, data:%#x [sn:%lli]\n", 614 storeWBIdx, inst->readPC(), 615 req->getPaddr(), *(inst->memData), 616 inst->seqNum); 617 618 // @todo: Remove this SC hack once the memory system handles it. 619 if (req->isLocked()) { 620 // Disable recording the result temporarily. Writing to 621 // misc regs normally updates the result, but this is not 622 // the desired behavior when handling store conditionals. 623 inst->recordResult = false; 624 bool success = TheISA::handleLockedWrite(inst.get(), req); 625 inst->recordResult = true; 626 627 if (!success) { 628 // Instantly complete this store. 629 DPRINTF(LSQUnit, "Store conditional [sn:%lli] failed. " 630 "Instantly completing it.\n", 631 inst->seqNum); 632 WritebackEvent *wb = new WritebackEvent(inst, data_pkt, this); 633 wb->schedule(curTick + 1); 634 delete state; 635 completeStore(storeWBIdx); 636 incrStIdx(storeWBIdx); 637 continue; 638 } 639 } else { 640 // Non-store conditionals do not need a writeback. 641 state->noWB = true; 642 } 643 644 if (!dcachePort->sendTiming(data_pkt)) { 645 if (data_pkt->result == Packet::BadAddress) { 646 panic("LSQ sent out a bad address for a completed store!"); 647 } 648 // Need to handle becoming blocked on a store. 649 DPRINTF(IEW, "D-Cache became blcoked when writing [sn:%lli], will" 650 "retry later\n", 651 inst->seqNum); 652 isStoreBlocked = true; 653 ++lsqCacheBlocked; 654 assert(retryPkt == NULL); 655 retryPkt = data_pkt; 656 lsq->setRetryTid(lsqID); 657 } else { 658 storePostSend(data_pkt); 659 } 660 } 661 662 // Not sure this should set it to 0. 663 usedPorts = 0; 664 665 assert(stores >= 0 && storesToWB >= 0); 666} 667 668/*template <class Impl> 669void 670LSQUnit<Impl>::removeMSHR(InstSeqNum seqNum) 671{ 672 list<InstSeqNum>::iterator mshr_it = find(mshrSeqNums.begin(), 673 mshrSeqNums.end(), 674 seqNum); 675 676 if (mshr_it != mshrSeqNums.end()) { 677 mshrSeqNums.erase(mshr_it); 678 DPRINTF(LSQUnit, "Removing MSHR. count = %i\n",mshrSeqNums.size()); 679 } 680}*/ 681 682template <class Impl> 683void 684LSQUnit<Impl>::squash(const InstSeqNum &squashed_num) 685{ 686 DPRINTF(LSQUnit, "Squashing until [sn:%lli]!" 687 "(Loads:%i Stores:%i)\n", squashed_num, loads, stores); 688 689 int load_idx = loadTail; 690 decrLdIdx(load_idx); 691 692 while (loads != 0 && loadQueue[load_idx]->seqNum > squashed_num) { 693 DPRINTF(LSQUnit,"Load Instruction PC %#x squashed, " 694 "[sn:%lli]\n", 695 loadQueue[load_idx]->readPC(), 696 loadQueue[load_idx]->seqNum); 697 698 if (isStalled() && load_idx == stallingLoadIdx) { 699 stalled = false; 700 stallingStoreIsn = 0; 701 stallingLoadIdx = 0; 702 } 703 704 // Clear the smart pointer to make sure it is decremented. 705 loadQueue[load_idx]->setSquashed(); 706 loadQueue[load_idx] = NULL; 707 --loads; 708 709 // Inefficient! 710 loadTail = load_idx; 711 712 decrLdIdx(load_idx); 713 ++lsqSquashedLoads; 714 } 715 716 if (isLoadBlocked) { 717 if (squashed_num < blockedLoadSeqNum) { 718 isLoadBlocked = false; 719 loadBlockedHandled = false; 720 blockedLoadSeqNum = 0; 721 } 722 } 723 724 int store_idx = storeTail; 725 decrStIdx(store_idx); 726 727 while (stores != 0 && 728 storeQueue[store_idx].inst->seqNum > squashed_num) { 729 // Instructions marked as can WB are already committed. 730 if (storeQueue[store_idx].canWB) { 731 break; 732 } 733 734 DPRINTF(LSQUnit,"Store Instruction PC %#x squashed, " 735 "idx:%i [sn:%lli]\n", 736 storeQueue[store_idx].inst->readPC(), 737 store_idx, storeQueue[store_idx].inst->seqNum); 738 739 // I don't think this can happen. It should have been cleared 740 // by the stalling load. 741 if (isStalled() && 742 storeQueue[store_idx].inst->seqNum == stallingStoreIsn) { 743 panic("Is stalled should have been cleared by stalling load!\n"); 744 stalled = false; 745 stallingStoreIsn = 0; 746 } 747 748 // Clear the smart pointer to make sure it is decremented. 749 storeQueue[store_idx].inst->setSquashed(); 750 storeQueue[store_idx].inst = NULL; 751 storeQueue[store_idx].canWB = 0; 752 753 storeQueue[store_idx].req = NULL; 754 --stores; 755 756 // Inefficient! 757 storeTail = store_idx; 758 759 decrStIdx(store_idx); 760 ++lsqSquashedStores; 761 } 762} 763 764template <class Impl> 765void 766LSQUnit<Impl>::storePostSend(PacketPtr pkt) 767{ 768 if (isStalled() && 769 storeQueue[storeWBIdx].inst->seqNum == stallingStoreIsn) { 770 DPRINTF(LSQUnit, "Unstalling, stalling store [sn:%lli] " 771 "load idx:%i\n", 772 stallingStoreIsn, stallingLoadIdx); 773 stalled = false; 774 stallingStoreIsn = 0; 775 iewStage->replayMemInst(loadQueue[stallingLoadIdx]); 776 } 777 778 if (!storeQueue[storeWBIdx].inst->isStoreConditional()) { 779 // The store is basically completed at this time. This 780 // only works so long as the checker doesn't try to 781 // verify the value in memory for stores. 782 storeQueue[storeWBIdx].inst->setCompleted(); 783#if USE_CHECKER 784 if (cpu->checker) { 785 cpu->checker->verify(storeQueue[storeWBIdx].inst); 786 } 787#endif 788 } 789 790 if (pkt->result != Packet::Success) { 791 DPRINTF(LSQUnit,"D-Cache Write Miss on idx:%i!\n", 792 storeWBIdx); 793 794 DPRINTF(Activity, "Active st accessing mem miss [sn:%lli]\n", 795 storeQueue[storeWBIdx].inst->seqNum); 796 797 //mshrSeqNums.push_back(storeQueue[storeWBIdx].inst->seqNum); 798 799 //DPRINTF(LSQUnit, "Added MSHR. count = %i\n",mshrSeqNums.size()); 800 801 // @todo: Increment stat here. 802 } else { 803 DPRINTF(LSQUnit,"D-Cache: Write Hit on idx:%i !\n", 804 storeWBIdx); 805 806 DPRINTF(Activity, "Active st accessing mem hit [sn:%lli]\n", 807 storeQueue[storeWBIdx].inst->seqNum); 808 } 809 810 incrStIdx(storeWBIdx); 811} 812 813template <class Impl> 814void 815LSQUnit<Impl>::writeback(DynInstPtr &inst, PacketPtr pkt) 816{ 817 iewStage->wakeCPU(); 818 819 // Squashed instructions do not need to complete their access. 820 if (inst->isSquashed()) { 821 iewStage->decrWb(inst->seqNum); 822 assert(!inst->isStore()); 823 ++lsqIgnoredResponses; 824 return; 825 } 826 827 if (!inst->isExecuted()) { 828 inst->setExecuted(); 829 830 // Complete access to copy data to proper place. 831 inst->completeAcc(pkt); 832 } 833 834 // Need to insert instruction into queue to commit 835 iewStage->instToCommit(inst); 836 837 iewStage->activityThisCycle(); 838} 839 840template <class Impl> 841void 842LSQUnit<Impl>::completeStore(int store_idx) 843{ 844 assert(storeQueue[store_idx].inst); 845 storeQueue[store_idx].completed = true; 846 --storesToWB; 847 // A bit conservative because a store completion may not free up entries, 848 // but hopefully avoids two store completions in one cycle from making 849 // the CPU tick twice. 850 cpu->wakeCPU(); 851 cpu->activityThisCycle(); 852 853 if (store_idx == storeHead) { 854 do { 855 incrStIdx(storeHead); 856 857 --stores; 858 } while (storeQueue[storeHead].completed && 859 storeHead != storeTail); 860 861 iewStage->updateLSQNextCycle = true; 862 } 863 864 DPRINTF(LSQUnit, "Completing store [sn:%lli], idx:%i, store head " 865 "idx:%i\n", 866 storeQueue[store_idx].inst->seqNum, store_idx, storeHead); 867 868 if (isStalled() && 869 storeQueue[store_idx].inst->seqNum == stallingStoreIsn) { 870 DPRINTF(LSQUnit, "Unstalling, stalling store [sn:%lli] " 871 "load idx:%i\n", 872 stallingStoreIsn, stallingLoadIdx); 873 stalled = false; 874 stallingStoreIsn = 0; 875 iewStage->replayMemInst(loadQueue[stallingLoadIdx]); 876 } 877 878 storeQueue[store_idx].inst->setCompleted(); 879 880 // Tell the checker we've completed this instruction. Some stores 881 // may get reported twice to the checker, but the checker can 882 // handle that case. 883#if USE_CHECKER 884 if (cpu->checker) { 885 cpu->checker->verify(storeQueue[store_idx].inst); 886 } 887#endif 888} 889 890template <class Impl> 891void 892LSQUnit<Impl>::recvRetry() 893{ 894 if (isStoreBlocked) { 895 assert(retryPkt != NULL); 896 897 if (dcachePort->sendTiming(retryPkt)) { 898 if (retryPkt->result == Packet::BadAddress) { 899 panic("LSQ sent out a bad address for a completed store!"); 900 } 901 storePostSend(retryPkt); 902 retryPkt = NULL; 903 isStoreBlocked = false; 904 lsq->setRetryTid(-1); 905 } else { 906 // Still blocked! 907 ++lsqCacheBlocked; 908 lsq->setRetryTid(lsqID); 909 } 910 } else if (isLoadBlocked) { 911 DPRINTF(LSQUnit, "Loads squash themselves and all younger insts, " 912 "no need to resend packet.\n"); 913 } else { 914 DPRINTF(LSQUnit, "Retry received but LSQ is no longer blocked.\n"); 915 } 916} 917 918template <class Impl> 919inline void 920LSQUnit<Impl>::incrStIdx(int &store_idx) 921{ 922 if (++store_idx >= SQEntries) 923 store_idx = 0; 924} 925 926template <class Impl> 927inline void 928LSQUnit<Impl>::decrStIdx(int &store_idx) 929{ 930 if (--store_idx < 0) 931 store_idx += SQEntries; 932} 933 934template <class Impl> 935inline void 936LSQUnit<Impl>::incrLdIdx(int &load_idx) 937{ 938 if (++load_idx >= LQEntries) 939 load_idx = 0; 940} 941 942template <class Impl> 943inline void 944LSQUnit<Impl>::decrLdIdx(int &load_idx) 945{ 946 if (--load_idx < 0) 947 load_idx += LQEntries; 948} 949 950template <class Impl> 951void 952LSQUnit<Impl>::dumpInsts() 953{ 954 cprintf("Load store queue: Dumping instructions.\n"); 955 cprintf("Load queue size: %i\n", loads); 956 cprintf("Load queue: "); 957 958 int load_idx = loadHead; 959 960 while (load_idx != loadTail && loadQueue[load_idx]) { 961 cprintf("%#x ", loadQueue[load_idx]->readPC()); 962 963 incrLdIdx(load_idx); 964 } 965 966 cprintf("Store queue size: %i\n", stores); 967 cprintf("Store queue: "); 968 969 int store_idx = storeHead; 970 971 while (store_idx != storeTail && storeQueue[store_idx].inst) { 972 cprintf("%#x ", storeQueue[store_idx].inst->readPC()); 973 974 incrStIdx(store_idx); 975 } 976 977 cprintf("\n"); 978} 979