CacheMemory.cc revision 11061
1/* 2 * Copyright (c) 1999-2012 Mark D. Hill and David A. Wood 3 * Copyright (c) 2013 Advanced Micro Devices, Inc. 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions are 8 * met: redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer; 10 * redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution; 13 * neither the name of the copyright holders nor the names of its 14 * contributors may be used to endorse or promote products derived from 15 * this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 18 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 19 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 20 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 21 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 22 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 23 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 27 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30#include "base/intmath.hh" 31#include "debug/RubyCache.hh" 32#include "debug/RubyCacheTrace.hh" 33#include "debug/RubyResourceStalls.hh" 34#include "debug/RubyStats.hh" 35#include "mem/protocol/AccessPermission.hh" 36#include "mem/ruby/structures/CacheMemory.hh" 37#include "mem/ruby/system/System.hh" 38 39using namespace std; 40 41ostream& 42operator<<(ostream& out, const CacheMemory& obj) 43{ 44 obj.print(out); 45 out << flush; 46 return out; 47} 48 49CacheMemory * 50RubyCacheParams::create() 51{ 52 return new CacheMemory(this); 53} 54 55CacheMemory::CacheMemory(const Params *p) 56 : SimObject(p), 57 dataArray(p->dataArrayBanks, p->dataAccessLatency, 58 p->start_index_bit, p->ruby_system), 59 tagArray(p->tagArrayBanks, p->tagAccessLatency, 60 p->start_index_bit, p->ruby_system) 61{ 62 m_cache_size = p->size; 63 m_cache_assoc = p->assoc; 64 m_replacementPolicy_ptr = p->replacement_policy; 65 m_replacementPolicy_ptr->setCache(this); 66 m_start_index_bit = p->start_index_bit; 67 m_is_instruction_only_cache = p->is_icache; 68 m_resource_stalls = p->resourceStalls; 69} 70 71void 72CacheMemory::init() 73{ 74 m_cache_num_sets = (m_cache_size / m_cache_assoc) / 75 RubySystem::getBlockSizeBytes(); 76 assert(m_cache_num_sets > 1); 77 m_cache_num_set_bits = floorLog2(m_cache_num_sets); 78 assert(m_cache_num_set_bits > 0); 79 80 m_cache.resize(m_cache_num_sets); 81 for (int i = 0; i < m_cache_num_sets; i++) { 82 m_cache[i].resize(m_cache_assoc); 83 for (int j = 0; j < m_cache_assoc; j++) { 84 m_cache[i][j] = NULL; 85 } 86 } 87} 88 89CacheMemory::~CacheMemory() 90{ 91 if (m_replacementPolicy_ptr != NULL) 92 delete m_replacementPolicy_ptr; 93 for (int i = 0; i < m_cache_num_sets; i++) { 94 for (int j = 0; j < m_cache_assoc; j++) { 95 delete m_cache[i][j]; 96 } 97 } 98} 99 100// convert a Address to its location in the cache 101int64_t 102CacheMemory::addressToCacheSet(Addr address) const 103{ 104 assert(address == makeLineAddress(address)); 105 return bitSelect(address, m_start_index_bit, 106 m_start_index_bit + m_cache_num_set_bits - 1); 107} 108 109// Given a cache index: returns the index of the tag in a set. 110// returns -1 if the tag is not found. 111int 112CacheMemory::findTagInSet(int64_t cacheSet, Addr tag) const 113{ 114 assert(tag == makeLineAddress(tag)); 115 // search the set for the tags 116 m5::hash_map<Addr, int>::const_iterator it = m_tag_index.find(tag); 117 if (it != m_tag_index.end()) 118 if (m_cache[cacheSet][it->second]->m_Permission != 119 AccessPermission_NotPresent) 120 return it->second; 121 return -1; // Not found 122} 123 124// Given a cache index: returns the index of the tag in a set. 125// returns -1 if the tag is not found. 126int 127CacheMemory::findTagInSetIgnorePermissions(int64_t cacheSet, 128 Addr tag) const 129{ 130 assert(tag == makeLineAddress(tag)); 131 // search the set for the tags 132 m5::hash_map<Addr, int>::const_iterator it = m_tag_index.find(tag); 133 if (it != m_tag_index.end()) 134 return it->second; 135 return -1; // Not found 136} 137 138// Given an unique cache block identifier (idx): return the valid address 139// stored by the cache block. If the block is invalid/notpresent, the 140// function returns the 0 address 141Addr 142CacheMemory::getAddressAtIdx(int idx) const 143{ 144 Addr tmp(0); 145 146 int set = idx / m_cache_assoc; 147 assert(set < m_cache_num_sets); 148 149 int way = idx - set * m_cache_assoc; 150 assert (way < m_cache_assoc); 151 152 AbstractCacheEntry* entry = m_cache[set][way]; 153 if (entry == NULL || 154 entry->m_Permission == AccessPermission_Invalid || 155 entry->m_Permission == AccessPermission_NotPresent) { 156 return tmp; 157 } 158 return entry->m_Address; 159} 160 161bool 162CacheMemory::tryCacheAccess(Addr address, RubyRequestType type, 163 DataBlock*& data_ptr) 164{ 165 assert(address == makeLineAddress(address)); 166 DPRINTF(RubyCache, "address: %s\n", address); 167 int64_t cacheSet = addressToCacheSet(address); 168 int loc = findTagInSet(cacheSet, address); 169 if (loc != -1) { 170 // Do we even have a tag match? 171 AbstractCacheEntry* entry = m_cache[cacheSet][loc]; 172 m_replacementPolicy_ptr->touch(cacheSet, loc, curTick()); 173 data_ptr = &(entry->getDataBlk()); 174 175 if (entry->m_Permission == AccessPermission_Read_Write) { 176 return true; 177 } 178 if ((entry->m_Permission == AccessPermission_Read_Only) && 179 (type == RubyRequestType_LD || type == RubyRequestType_IFETCH)) { 180 return true; 181 } 182 // The line must not be accessible 183 } 184 data_ptr = NULL; 185 return false; 186} 187 188bool 189CacheMemory::testCacheAccess(Addr address, RubyRequestType type, 190 DataBlock*& data_ptr) 191{ 192 assert(address == makeLineAddress(address)); 193 DPRINTF(RubyCache, "address: %s\n", address); 194 int64_t cacheSet = addressToCacheSet(address); 195 int loc = findTagInSet(cacheSet, address); 196 197 if (loc != -1) { 198 // Do we even have a tag match? 199 AbstractCacheEntry* entry = m_cache[cacheSet][loc]; 200 m_replacementPolicy_ptr->touch(cacheSet, loc, curTick()); 201 data_ptr = &(entry->getDataBlk()); 202 203 return m_cache[cacheSet][loc]->m_Permission != 204 AccessPermission_NotPresent; 205 } 206 207 data_ptr = NULL; 208 return false; 209} 210 211// tests to see if an address is present in the cache 212bool 213CacheMemory::isTagPresent(Addr address) const 214{ 215 assert(address == makeLineAddress(address)); 216 int64_t cacheSet = addressToCacheSet(address); 217 int loc = findTagInSet(cacheSet, address); 218 219 if (loc == -1) { 220 // We didn't find the tag 221 DPRINTF(RubyCache, "No tag match for address: %s\n", address); 222 return false; 223 } 224 DPRINTF(RubyCache, "address: %s found\n", address); 225 return true; 226} 227 228// Returns true if there is: 229// a) a tag match on this address or there is 230// b) an unused line in the same cache "way" 231bool 232CacheMemory::cacheAvail(Addr address) const 233{ 234 assert(address == makeLineAddress(address)); 235 236 int64_t cacheSet = addressToCacheSet(address); 237 238 for (int i = 0; i < m_cache_assoc; i++) { 239 AbstractCacheEntry* entry = m_cache[cacheSet][i]; 240 if (entry != NULL) { 241 if (entry->m_Address == address || 242 entry->m_Permission == AccessPermission_NotPresent) { 243 // Already in the cache or we found an empty entry 244 return true; 245 } 246 } else { 247 return true; 248 } 249 } 250 return false; 251} 252 253AbstractCacheEntry* 254CacheMemory::allocate(Addr address, AbstractCacheEntry* entry, bool touch) 255{ 256 assert(address == makeLineAddress(address)); 257 assert(!isTagPresent(address)); 258 assert(cacheAvail(address)); 259 DPRINTF(RubyCache, "address: %s\n", address); 260 261 // Find the first open slot 262 int64_t cacheSet = addressToCacheSet(address); 263 std::vector<AbstractCacheEntry*> &set = m_cache[cacheSet]; 264 for (int i = 0; i < m_cache_assoc; i++) { 265 if (!set[i] || set[i]->m_Permission == AccessPermission_NotPresent) { 266 set[i] = entry; // Init entry 267 set[i]->m_Address = address; 268 set[i]->m_Permission = AccessPermission_Invalid; 269 DPRINTF(RubyCache, "Allocate clearing lock for addr: %x\n", 270 address); 271 set[i]->m_locked = -1; 272 m_tag_index[address] = i; 273 274 if (touch) { 275 m_replacementPolicy_ptr->touch(cacheSet, i, curTick()); 276 } 277 278 return entry; 279 } 280 } 281 panic("Allocate didn't find an available entry"); 282} 283 284void 285CacheMemory::deallocate(Addr address) 286{ 287 assert(address == makeLineAddress(address)); 288 assert(isTagPresent(address)); 289 DPRINTF(RubyCache, "address: %s\n", address); 290 int64_t cacheSet = addressToCacheSet(address); 291 int loc = findTagInSet(cacheSet, address); 292 if (loc != -1) { 293 delete m_cache[cacheSet][loc]; 294 m_cache[cacheSet][loc] = NULL; 295 m_tag_index.erase(address); 296 } 297} 298 299// Returns with the physical address of the conflicting cache line 300Addr 301CacheMemory::cacheProbe(Addr address) const 302{ 303 assert(address == makeLineAddress(address)); 304 assert(!cacheAvail(address)); 305 306 int64_t cacheSet = addressToCacheSet(address); 307 return m_cache[cacheSet][m_replacementPolicy_ptr->getVictim(cacheSet)]-> 308 m_Address; 309} 310 311// looks an address up in the cache 312AbstractCacheEntry* 313CacheMemory::lookup(Addr address) 314{ 315 assert(address == makeLineAddress(address)); 316 int64_t cacheSet = addressToCacheSet(address); 317 int loc = findTagInSet(cacheSet, address); 318 if(loc == -1) return NULL; 319 return m_cache[cacheSet][loc]; 320} 321 322// looks an address up in the cache 323const AbstractCacheEntry* 324CacheMemory::lookup(Addr address) const 325{ 326 assert(address == makeLineAddress(address)); 327 int64_t cacheSet = addressToCacheSet(address); 328 int loc = findTagInSet(cacheSet, address); 329 if(loc == -1) return NULL; 330 return m_cache[cacheSet][loc]; 331} 332 333// Sets the most recently used bit for a cache block 334void 335CacheMemory::setMRU(Addr address) 336{ 337 int64_t cacheSet = addressToCacheSet(address); 338 int loc = findTagInSet(cacheSet, address); 339 340 if(loc != -1) 341 m_replacementPolicy_ptr->touch(cacheSet, loc, curTick()); 342} 343 344void 345CacheMemory::recordCacheContents(int cntrl, CacheRecorder* tr) const 346{ 347 uint64_t warmedUpBlocks = 0; 348 uint64_t totalBlocks M5_VAR_USED = (uint64_t)m_cache_num_sets * 349 (uint64_t)m_cache_assoc; 350 351 for (int i = 0; i < m_cache_num_sets; i++) { 352 for (int j = 0; j < m_cache_assoc; j++) { 353 if (m_cache[i][j] != NULL) { 354 AccessPermission perm = m_cache[i][j]->m_Permission; 355 RubyRequestType request_type = RubyRequestType_NULL; 356 if (perm == AccessPermission_Read_Only) { 357 if (m_is_instruction_only_cache) { 358 request_type = RubyRequestType_IFETCH; 359 } else { 360 request_type = RubyRequestType_LD; 361 } 362 } else if (perm == AccessPermission_Read_Write) { 363 request_type = RubyRequestType_ST; 364 } 365 366 if (request_type != RubyRequestType_NULL) { 367 tr->addRecord(cntrl, m_cache[i][j]->m_Address, 368 0, request_type, 369 m_replacementPolicy_ptr->getLastAccess(i, j), 370 m_cache[i][j]->getDataBlk()); 371 warmedUpBlocks++; 372 } 373 } 374 } 375 } 376 377 DPRINTF(RubyCacheTrace, "%s: %lli blocks of %lli total blocks" 378 "recorded %.2f%% \n", name().c_str(), warmedUpBlocks, 379 totalBlocks, (float(warmedUpBlocks) / float(totalBlocks)) * 100.0); 380} 381 382void 383CacheMemory::print(ostream& out) const 384{ 385 out << "Cache dump: " << name() << endl; 386 for (int i = 0; i < m_cache_num_sets; i++) { 387 for (int j = 0; j < m_cache_assoc; j++) { 388 if (m_cache[i][j] != NULL) { 389 out << " Index: " << i 390 << " way: " << j 391 << " entry: " << *m_cache[i][j] << endl; 392 } else { 393 out << " Index: " << i 394 << " way: " << j 395 << " entry: NULL" << endl; 396 } 397 } 398 } 399} 400 401void 402CacheMemory::printData(ostream& out) const 403{ 404 out << "printData() not supported" << endl; 405} 406 407void 408CacheMemory::setLocked(Addr address, int context) 409{ 410 DPRINTF(RubyCache, "Setting Lock for addr: %x to %d\n", address, context); 411 assert(address == makeLineAddress(address)); 412 int64_t cacheSet = addressToCacheSet(address); 413 int loc = findTagInSet(cacheSet, address); 414 assert(loc != -1); 415 m_cache[cacheSet][loc]->setLocked(context); 416} 417 418void 419CacheMemory::clearLocked(Addr address) 420{ 421 DPRINTF(RubyCache, "Clear Lock for addr: %x\n", address); 422 assert(address == makeLineAddress(address)); 423 int64_t cacheSet = addressToCacheSet(address); 424 int loc = findTagInSet(cacheSet, address); 425 assert(loc != -1); 426 m_cache[cacheSet][loc]->clearLocked(); 427} 428 429bool 430CacheMemory::isLocked(Addr address, int context) 431{ 432 assert(address == makeLineAddress(address)); 433 int64_t cacheSet = addressToCacheSet(address); 434 int loc = findTagInSet(cacheSet, address); 435 assert(loc != -1); 436 DPRINTF(RubyCache, "Testing Lock for addr: %llx cur %d con %d\n", 437 address, m_cache[cacheSet][loc]->m_locked, context); 438 return m_cache[cacheSet][loc]->isLocked(context); 439} 440 441void 442CacheMemory::regStats() 443{ 444 m_demand_hits 445 .name(name() + ".demand_hits") 446 .desc("Number of cache demand hits") 447 ; 448 449 m_demand_misses 450 .name(name() + ".demand_misses") 451 .desc("Number of cache demand misses") 452 ; 453 454 m_demand_accesses 455 .name(name() + ".demand_accesses") 456 .desc("Number of cache demand accesses") 457 ; 458 459 m_demand_accesses = m_demand_hits + m_demand_misses; 460 461 m_sw_prefetches 462 .name(name() + ".total_sw_prefetches") 463 .desc("Number of software prefetches") 464 .flags(Stats::nozero) 465 ; 466 467 m_hw_prefetches 468 .name(name() + ".total_hw_prefetches") 469 .desc("Number of hardware prefetches") 470 .flags(Stats::nozero) 471 ; 472 473 m_prefetches 474 .name(name() + ".total_prefetches") 475 .desc("Number of prefetches") 476 .flags(Stats::nozero) 477 ; 478 479 m_prefetches = m_sw_prefetches + m_hw_prefetches; 480 481 m_accessModeType 482 .init(RubyRequestType_NUM) 483 .name(name() + ".access_mode") 484 .flags(Stats::pdf | Stats::total) 485 ; 486 for (int i = 0; i < RubyAccessMode_NUM; i++) { 487 m_accessModeType 488 .subname(i, RubyAccessMode_to_string(RubyAccessMode(i))) 489 .flags(Stats::nozero) 490 ; 491 } 492 493 numDataArrayReads 494 .name(name() + ".num_data_array_reads") 495 .desc("number of data array reads") 496 .flags(Stats::nozero) 497 ; 498 499 numDataArrayWrites 500 .name(name() + ".num_data_array_writes") 501 .desc("number of data array writes") 502 .flags(Stats::nozero) 503 ; 504 505 numTagArrayReads 506 .name(name() + ".num_tag_array_reads") 507 .desc("number of tag array reads") 508 .flags(Stats::nozero) 509 ; 510 511 numTagArrayWrites 512 .name(name() + ".num_tag_array_writes") 513 .desc("number of tag array writes") 514 .flags(Stats::nozero) 515 ; 516 517 numTagArrayStalls 518 .name(name() + ".num_tag_array_stalls") 519 .desc("number of stalls caused by tag array") 520 .flags(Stats::nozero) 521 ; 522 523 numDataArrayStalls 524 .name(name() + ".num_data_array_stalls") 525 .desc("number of stalls caused by data array") 526 .flags(Stats::nozero) 527 ; 528} 529 530// assumption: SLICC generated files will only call this function 531// once **all** resources are granted 532void 533CacheMemory::recordRequestType(CacheRequestType requestType, Addr addr) 534{ 535 DPRINTF(RubyStats, "Recorded statistic: %s\n", 536 CacheRequestType_to_string(requestType)); 537 switch(requestType) { 538 case CacheRequestType_DataArrayRead: 539 if (m_resource_stalls) 540 dataArray.reserve(addressToCacheSet(addr)); 541 numDataArrayReads++; 542 return; 543 case CacheRequestType_DataArrayWrite: 544 if (m_resource_stalls) 545 dataArray.reserve(addressToCacheSet(addr)); 546 numDataArrayWrites++; 547 return; 548 case CacheRequestType_TagArrayRead: 549 if (m_resource_stalls) 550 tagArray.reserve(addressToCacheSet(addr)); 551 numTagArrayReads++; 552 return; 553 case CacheRequestType_TagArrayWrite: 554 if (m_resource_stalls) 555 tagArray.reserve(addressToCacheSet(addr)); 556 numTagArrayWrites++; 557 return; 558 default: 559 warn("CacheMemory access_type not found: %s", 560 CacheRequestType_to_string(requestType)); 561 } 562} 563 564bool 565CacheMemory::checkResourceAvailable(CacheResourceType res, Addr addr) 566{ 567 if (!m_resource_stalls) { 568 return true; 569 } 570 571 if (res == CacheResourceType_TagArray) { 572 if (tagArray.tryAccess(addressToCacheSet(addr))) return true; 573 else { 574 DPRINTF(RubyResourceStalls, 575 "Tag array stall on addr %s in set %d\n", 576 addr, addressToCacheSet(addr)); 577 numTagArrayStalls++; 578 return false; 579 } 580 } else if (res == CacheResourceType_DataArray) { 581 if (dataArray.tryAccess(addressToCacheSet(addr))) return true; 582 else { 583 DPRINTF(RubyResourceStalls, 584 "Data array stall on addr %s in set %d\n", 585 addr, addressToCacheSet(addr)); 586 numDataArrayStalls++; 587 return false; 588 } 589 } else { 590 assert(false); 591 return true; 592 } 593} 594 595bool 596CacheMemory::isBlockInvalid(int64_t cache_set, int64_t loc) 597{ 598 return (m_cache[cache_set][loc]->m_Permission == AccessPermission_Invalid); 599} 600 601bool 602CacheMemory::isBlockNotBusy(int64_t cache_set, int64_t loc) 603{ 604 return (m_cache[cache_set][loc]->m_Permission != AccessPermission_Busy); 605} 606