backend_impl.cc revision e5d81f57cb97b3b6b7fccc9c5610d21eb81db09d
1// Copyright (c) 2012 The Chromium Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style license that can be 3// found in the LICENSE file. 4 5#include "net/disk_cache/blockfile/backend_impl.h" 6 7#include "base/bind.h" 8#include "base/bind_helpers.h" 9#include "base/file_util.h" 10#include "base/files/file_path.h" 11#include "base/hash.h" 12#include "base/message_loop/message_loop.h" 13#include "base/metrics/field_trial.h" 14#include "base/metrics/histogram.h" 15#include "base/metrics/stats_counters.h" 16#include "base/rand_util.h" 17#include "base/strings/string_util.h" 18#include "base/strings/stringprintf.h" 19#include "base/sys_info.h" 20#include "base/threading/thread_restrictions.h" 21#include "base/time/time.h" 22#include "base/timer/timer.h" 23#include "net/base/net_errors.h" 24#include "net/disk_cache/blockfile/disk_format.h" 25#include "net/disk_cache/blockfile/entry_impl.h" 26#include "net/disk_cache/blockfile/errors.h" 27#include "net/disk_cache/blockfile/experiments.h" 28#include "net/disk_cache/blockfile/file.h" 29#include "net/disk_cache/blockfile/histogram_macros.h" 30#include "net/disk_cache/cache_util.h" 31 32// Provide a BackendImpl object to macros from histogram_macros.h. 33#define CACHE_UMA_BACKEND_IMPL_OBJ this 34 35using base::Time; 36using base::TimeDelta; 37using base::TimeTicks; 38 39namespace { 40 41const char* kIndexName = "index"; 42 43// Seems like ~240 MB correspond to less than 50k entries for 99% of the people. 44// Note that the actual target is to keep the index table load factor under 55% 45// for most users. 46const int k64kEntriesStore = 240 * 1000 * 1000; 47const int kBaseTableLen = 64 * 1024; 48 49// Avoid trimming the cache for the first 5 minutes (10 timer ticks). 50const int kTrimDelay = 10; 51 52int DesiredIndexTableLen(int32 storage_size) { 53 if (storage_size <= k64kEntriesStore) 54 return kBaseTableLen; 55 if (storage_size <= k64kEntriesStore * 2) 56 return kBaseTableLen * 2; 57 if (storage_size <= k64kEntriesStore * 4) 58 return kBaseTableLen * 4; 59 if (storage_size <= k64kEntriesStore * 8) 60 return kBaseTableLen * 8; 61 62 // The biggest storage_size for int32 requires a 4 MB table. 63 return kBaseTableLen * 16; 64} 65 66int MaxStorageSizeForTable(int table_len) { 67 return table_len * (k64kEntriesStore / kBaseTableLen); 68} 69 70size_t GetIndexSize(int table_len) { 71 size_t table_size = sizeof(disk_cache::CacheAddr) * table_len; 72 return sizeof(disk_cache::IndexHeader) + table_size; 73} 74 75// ------------------------------------------------------------------------ 76 77// Sets group for the current experiment. Returns false if the files should be 78// discarded. 79bool InitExperiment(disk_cache::IndexHeader* header, bool cache_created) { 80 if (header->experiment == disk_cache::EXPERIMENT_OLD_FILE1 || 81 header->experiment == disk_cache::EXPERIMENT_OLD_FILE2) { 82 // Discard current cache. 83 return false; 84 } 85 86 if (base::FieldTrialList::FindFullName("SimpleCacheTrial") == 87 "ExperimentControl") { 88 if (cache_created) { 89 header->experiment = disk_cache::EXPERIMENT_SIMPLE_CONTROL; 90 return true; 91 } 92 return header->experiment == disk_cache::EXPERIMENT_SIMPLE_CONTROL; 93 } 94 95 header->experiment = disk_cache::NO_EXPERIMENT; 96 return true; 97} 98 99// A callback to perform final cleanup on the background thread. 100void FinalCleanupCallback(disk_cache::BackendImpl* backend) { 101 backend->CleanupCache(); 102} 103 104} // namespace 105 106// ------------------------------------------------------------------------ 107 108namespace disk_cache { 109 110BackendImpl::BackendImpl(const base::FilePath& path, 111 base::MessageLoopProxy* cache_thread, 112 net::NetLog* net_log) 113 : background_queue_(this, cache_thread), 114 path_(path), 115 block_files_(path), 116 mask_(0), 117 max_size_(0), 118 up_ticks_(0), 119 cache_type_(net::DISK_CACHE), 120 uma_report_(0), 121 user_flags_(0), 122 init_(false), 123 restarted_(false), 124 unit_test_(false), 125 read_only_(false), 126 disabled_(false), 127 new_eviction_(false), 128 first_timer_(true), 129 user_load_(false), 130 net_log_(net_log), 131 done_(true, false), 132 ptr_factory_(this) { 133} 134 135BackendImpl::BackendImpl(const base::FilePath& path, 136 uint32 mask, 137 base::MessageLoopProxy* cache_thread, 138 net::NetLog* net_log) 139 : background_queue_(this, cache_thread), 140 path_(path), 141 block_files_(path), 142 mask_(mask), 143 max_size_(0), 144 up_ticks_(0), 145 cache_type_(net::DISK_CACHE), 146 uma_report_(0), 147 user_flags_(kMask), 148 init_(false), 149 restarted_(false), 150 unit_test_(false), 151 read_only_(false), 152 disabled_(false), 153 new_eviction_(false), 154 first_timer_(true), 155 user_load_(false), 156 net_log_(net_log), 157 done_(true, false), 158 ptr_factory_(this) { 159} 160 161BackendImpl::~BackendImpl() { 162 if (user_flags_ & kNoRandom) { 163 // This is a unit test, so we want to be strict about not leaking entries 164 // and completing all the work. 165 background_queue_.WaitForPendingIO(); 166 } else { 167 // This is most likely not a test, so we want to do as little work as 168 // possible at this time, at the price of leaving dirty entries behind. 169 background_queue_.DropPendingIO(); 170 } 171 172 if (background_queue_.BackgroundIsCurrentThread()) { 173 // Unit tests may use the same thread for everything. 174 CleanupCache(); 175 } else { 176 background_queue_.background_thread()->PostTask( 177 FROM_HERE, base::Bind(&FinalCleanupCallback, base::Unretained(this))); 178 // http://crbug.com/74623 179 base::ThreadRestrictions::ScopedAllowWait allow_wait; 180 done_.Wait(); 181 } 182} 183 184int BackendImpl::Init(const CompletionCallback& callback) { 185 background_queue_.Init(callback); 186 return net::ERR_IO_PENDING; 187} 188 189int BackendImpl::SyncInit() { 190#if defined(NET_BUILD_STRESS_CACHE) 191 // Start evictions right away. 192 up_ticks_ = kTrimDelay * 2; 193#endif 194 DCHECK(!init_); 195 if (init_) 196 return net::ERR_FAILED; 197 198 bool create_files = false; 199 if (!InitBackingStore(&create_files)) { 200 ReportError(ERR_STORAGE_ERROR); 201 return net::ERR_FAILED; 202 } 203 204 num_refs_ = num_pending_io_ = max_refs_ = 0; 205 entry_count_ = byte_count_ = 0; 206 207 bool should_create_timer = false; 208 if (!restarted_) { 209 buffer_bytes_ = 0; 210 trace_object_ = TraceObject::GetTraceObject(); 211 should_create_timer = true; 212 } 213 214 init_ = true; 215 Trace("Init"); 216 217 if (data_->header.experiment != NO_EXPERIMENT && 218 cache_type_ != net::DISK_CACHE) { 219 // No experiment for other caches. 220 return net::ERR_FAILED; 221 } 222 223 if (!(user_flags_ & kNoRandom)) { 224 // The unit test controls directly what to test. 225 new_eviction_ = (cache_type_ == net::DISK_CACHE); 226 } 227 228 if (!CheckIndex()) { 229 ReportError(ERR_INIT_FAILED); 230 return net::ERR_FAILED; 231 } 232 233 if (!restarted_ && (create_files || !data_->header.num_entries)) 234 ReportError(ERR_CACHE_CREATED); 235 236 if (!(user_flags_ & kNoRandom) && cache_type_ == net::DISK_CACHE && 237 !InitExperiment(&data_->header, create_files)) { 238 return net::ERR_FAILED; 239 } 240 241 // We don't care if the value overflows. The only thing we care about is that 242 // the id cannot be zero, because that value is used as "not dirty". 243 // Increasing the value once per second gives us many years before we start 244 // having collisions. 245 data_->header.this_id++; 246 if (!data_->header.this_id) 247 data_->header.this_id++; 248 249 bool previous_crash = (data_->header.crash != 0); 250 data_->header.crash = 1; 251 252 if (!block_files_.Init(create_files)) 253 return net::ERR_FAILED; 254 255 // We want to minimize the changes to cache for an AppCache. 256 if (cache_type() == net::APP_CACHE) { 257 DCHECK(!new_eviction_); 258 read_only_ = true; 259 } else if (cache_type() == net::SHADER_CACHE) { 260 DCHECK(!new_eviction_); 261 } 262 263 eviction_.Init(this); 264 265 // stats_ and rankings_ may end up calling back to us so we better be enabled. 266 disabled_ = false; 267 if (!InitStats()) 268 return net::ERR_FAILED; 269 270 disabled_ = !rankings_.Init(this, new_eviction_); 271 272#if defined(STRESS_CACHE_EXTENDED_VALIDATION) 273 trace_object_->EnableTracing(false); 274 int sc = SelfCheck(); 275 if (sc < 0 && sc != ERR_NUM_ENTRIES_MISMATCH) 276 NOTREACHED(); 277 trace_object_->EnableTracing(true); 278#endif 279 280 if (previous_crash) { 281 ReportError(ERR_PREVIOUS_CRASH); 282 } else if (!restarted_) { 283 ReportError(ERR_NO_ERROR); 284 } 285 286 FlushIndex(); 287 288 if (!disabled_ && should_create_timer) { 289 // Create a recurrent timer of 30 secs. 290 int timer_delay = unit_test_ ? 1000 : 30000; 291 timer_.reset(new base::RepeatingTimer<BackendImpl>()); 292 timer_->Start(FROM_HERE, TimeDelta::FromMilliseconds(timer_delay), this, 293 &BackendImpl::OnStatsTimer); 294 } 295 296 return disabled_ ? net::ERR_FAILED : net::OK; 297} 298 299void BackendImpl::CleanupCache() { 300 Trace("Backend Cleanup"); 301 eviction_.Stop(); 302 timer_.reset(); 303 304 if (init_) { 305 StoreStats(); 306 if (data_) 307 data_->header.crash = 0; 308 309 if (user_flags_ & kNoRandom) { 310 // This is a net_unittest, verify that we are not 'leaking' entries. 311 File::WaitForPendingIO(&num_pending_io_); 312 DCHECK(!num_refs_); 313 } else { 314 File::DropPendingIO(); 315 } 316 } 317 block_files_.CloseFiles(); 318 FlushIndex(); 319 index_ = NULL; 320 ptr_factory_.InvalidateWeakPtrs(); 321 done_.Signal(); 322} 323 324// ------------------------------------------------------------------------ 325 326int BackendImpl::OpenPrevEntry(void** iter, Entry** prev_entry, 327 const CompletionCallback& callback) { 328 DCHECK(!callback.is_null()); 329 background_queue_.OpenPrevEntry(iter, prev_entry, callback); 330 return net::ERR_IO_PENDING; 331} 332 333int BackendImpl::SyncOpenEntry(const std::string& key, Entry** entry) { 334 DCHECK(entry); 335 *entry = OpenEntryImpl(key); 336 return (*entry) ? net::OK : net::ERR_FAILED; 337} 338 339int BackendImpl::SyncCreateEntry(const std::string& key, Entry** entry) { 340 DCHECK(entry); 341 *entry = CreateEntryImpl(key); 342 return (*entry) ? net::OK : net::ERR_FAILED; 343} 344 345int BackendImpl::SyncDoomEntry(const std::string& key) { 346 if (disabled_) 347 return net::ERR_FAILED; 348 349 EntryImpl* entry = OpenEntryImpl(key); 350 if (!entry) 351 return net::ERR_FAILED; 352 353 entry->DoomImpl(); 354 entry->Release(); 355 return net::OK; 356} 357 358int BackendImpl::SyncDoomAllEntries() { 359 // This is not really an error, but it is an interesting condition. 360 ReportError(ERR_CACHE_DOOMED); 361 stats_.OnEvent(Stats::DOOM_CACHE); 362 if (!num_refs_) { 363 RestartCache(false); 364 return disabled_ ? net::ERR_FAILED : net::OK; 365 } else { 366 if (disabled_) 367 return net::ERR_FAILED; 368 369 eviction_.TrimCache(true); 370 return net::OK; 371 } 372} 373 374int BackendImpl::SyncDoomEntriesBetween(const base::Time initial_time, 375 const base::Time end_time) { 376 DCHECK_NE(net::APP_CACHE, cache_type_); 377 if (end_time.is_null()) 378 return SyncDoomEntriesSince(initial_time); 379 380 DCHECK(end_time >= initial_time); 381 382 if (disabled_) 383 return net::ERR_FAILED; 384 385 EntryImpl* node; 386 void* iter = NULL; 387 EntryImpl* next = OpenNextEntryImpl(&iter); 388 if (!next) 389 return net::OK; 390 391 while (next) { 392 node = next; 393 next = OpenNextEntryImpl(&iter); 394 395 if (node->GetLastUsed() >= initial_time && 396 node->GetLastUsed() < end_time) { 397 node->DoomImpl(); 398 } else if (node->GetLastUsed() < initial_time) { 399 if (next) 400 next->Release(); 401 next = NULL; 402 SyncEndEnumeration(iter); 403 } 404 405 node->Release(); 406 } 407 408 return net::OK; 409} 410 411// We use OpenNextEntryImpl to retrieve elements from the cache, until we get 412// entries that are too old. 413int BackendImpl::SyncDoomEntriesSince(const base::Time initial_time) { 414 DCHECK_NE(net::APP_CACHE, cache_type_); 415 if (disabled_) 416 return net::ERR_FAILED; 417 418 stats_.OnEvent(Stats::DOOM_RECENT); 419 for (;;) { 420 void* iter = NULL; 421 EntryImpl* entry = OpenNextEntryImpl(&iter); 422 if (!entry) 423 return net::OK; 424 425 if (initial_time > entry->GetLastUsed()) { 426 entry->Release(); 427 SyncEndEnumeration(iter); 428 return net::OK; 429 } 430 431 entry->DoomImpl(); 432 entry->Release(); 433 SyncEndEnumeration(iter); // Dooming the entry invalidates the iterator. 434 } 435} 436 437int BackendImpl::SyncOpenNextEntry(void** iter, Entry** next_entry) { 438 *next_entry = OpenNextEntryImpl(iter); 439 return (*next_entry) ? net::OK : net::ERR_FAILED; 440} 441 442int BackendImpl::SyncOpenPrevEntry(void** iter, Entry** prev_entry) { 443 *prev_entry = OpenPrevEntryImpl(iter); 444 return (*prev_entry) ? net::OK : net::ERR_FAILED; 445} 446 447void BackendImpl::SyncEndEnumeration(void* iter) { 448 scoped_ptr<Rankings::Iterator> iterator( 449 reinterpret_cast<Rankings::Iterator*>(iter)); 450} 451 452void BackendImpl::SyncOnExternalCacheHit(const std::string& key) { 453 if (disabled_) 454 return; 455 456 uint32 hash = base::Hash(key); 457 bool error; 458 EntryImpl* cache_entry = MatchEntry(key, hash, false, Addr(), &error); 459 if (cache_entry) { 460 if (ENTRY_NORMAL == cache_entry->entry()->Data()->state) { 461 UpdateRank(cache_entry, cache_type() == net::SHADER_CACHE); 462 } 463 cache_entry->Release(); 464 } 465} 466 467EntryImpl* BackendImpl::OpenEntryImpl(const std::string& key) { 468 if (disabled_) 469 return NULL; 470 471 TimeTicks start = TimeTicks::Now(); 472 uint32 hash = base::Hash(key); 473 Trace("Open hash 0x%x", hash); 474 475 bool error; 476 EntryImpl* cache_entry = MatchEntry(key, hash, false, Addr(), &error); 477 if (cache_entry && ENTRY_NORMAL != cache_entry->entry()->Data()->state) { 478 // The entry was already evicted. 479 cache_entry->Release(); 480 cache_entry = NULL; 481 } 482 483 int current_size = data_->header.num_bytes / (1024 * 1024); 484 int64 total_hours = stats_.GetCounter(Stats::TIMER) / 120; 485 int64 no_use_hours = stats_.GetCounter(Stats::LAST_REPORT_TIMER) / 120; 486 int64 use_hours = total_hours - no_use_hours; 487 488 if (!cache_entry) { 489 CACHE_UMA(AGE_MS, "OpenTime.Miss", 0, start); 490 CACHE_UMA(COUNTS_10000, "AllOpenBySize.Miss", 0, current_size); 491 CACHE_UMA(HOURS, "AllOpenByTotalHours.Miss", 0, total_hours); 492 CACHE_UMA(HOURS, "AllOpenByUseHours.Miss", 0, use_hours); 493 stats_.OnEvent(Stats::OPEN_MISS); 494 return NULL; 495 } 496 497 eviction_.OnOpenEntry(cache_entry); 498 entry_count_++; 499 500 Trace("Open hash 0x%x end: 0x%x", hash, 501 cache_entry->entry()->address().value()); 502 CACHE_UMA(AGE_MS, "OpenTime", 0, start); 503 CACHE_UMA(COUNTS_10000, "AllOpenBySize.Hit", 0, current_size); 504 CACHE_UMA(HOURS, "AllOpenByTotalHours.Hit", 0, total_hours); 505 CACHE_UMA(HOURS, "AllOpenByUseHours.Hit", 0, use_hours); 506 stats_.OnEvent(Stats::OPEN_HIT); 507 SIMPLE_STATS_COUNTER("disk_cache.hit"); 508 return cache_entry; 509} 510 511EntryImpl* BackendImpl::CreateEntryImpl(const std::string& key) { 512 if (disabled_ || key.empty()) 513 return NULL; 514 515 TimeTicks start = TimeTicks::Now(); 516 uint32 hash = base::Hash(key); 517 Trace("Create hash 0x%x", hash); 518 519 scoped_refptr<EntryImpl> parent; 520 Addr entry_address(data_->table[hash & mask_]); 521 if (entry_address.is_initialized()) { 522 // We have an entry already. It could be the one we are looking for, or just 523 // a hash conflict. 524 bool error; 525 EntryImpl* old_entry = MatchEntry(key, hash, false, Addr(), &error); 526 if (old_entry) 527 return ResurrectEntry(old_entry); 528 529 EntryImpl* parent_entry = MatchEntry(key, hash, true, Addr(), &error); 530 DCHECK(!error); 531 if (parent_entry) { 532 parent.swap(&parent_entry); 533 } else if (data_->table[hash & mask_]) { 534 // We should have corrected the problem. 535 NOTREACHED(); 536 return NULL; 537 } 538 } 539 540 // The general flow is to allocate disk space and initialize the entry data, 541 // followed by saving that to disk, then linking the entry though the index 542 // and finally through the lists. If there is a crash in this process, we may 543 // end up with: 544 // a. Used, unreferenced empty blocks on disk (basically just garbage). 545 // b. Used, unreferenced but meaningful data on disk (more garbage). 546 // c. A fully formed entry, reachable only through the index. 547 // d. A fully formed entry, also reachable through the lists, but still dirty. 548 // 549 // Anything after (b) can be automatically cleaned up. We may consider saving 550 // the current operation (as we do while manipulating the lists) so that we 551 // can detect and cleanup (a) and (b). 552 553 int num_blocks = EntryImpl::NumBlocksForEntry(key.size()); 554 if (!block_files_.CreateBlock(BLOCK_256, num_blocks, &entry_address)) { 555 LOG(ERROR) << "Create entry failed " << key.c_str(); 556 stats_.OnEvent(Stats::CREATE_ERROR); 557 return NULL; 558 } 559 560 Addr node_address(0); 561 if (!block_files_.CreateBlock(RANKINGS, 1, &node_address)) { 562 block_files_.DeleteBlock(entry_address, false); 563 LOG(ERROR) << "Create entry failed " << key.c_str(); 564 stats_.OnEvent(Stats::CREATE_ERROR); 565 return NULL; 566 } 567 568 scoped_refptr<EntryImpl> cache_entry( 569 new EntryImpl(this, entry_address, false)); 570 IncreaseNumRefs(); 571 572 if (!cache_entry->CreateEntry(node_address, key, hash)) { 573 block_files_.DeleteBlock(entry_address, false); 574 block_files_.DeleteBlock(node_address, false); 575 LOG(ERROR) << "Create entry failed " << key.c_str(); 576 stats_.OnEvent(Stats::CREATE_ERROR); 577 return NULL; 578 } 579 580 cache_entry->BeginLogging(net_log_, true); 581 582 // We are not failing the operation; let's add this to the map. 583 open_entries_[entry_address.value()] = cache_entry.get(); 584 585 // Save the entry. 586 cache_entry->entry()->Store(); 587 cache_entry->rankings()->Store(); 588 IncreaseNumEntries(); 589 entry_count_++; 590 591 // Link this entry through the index. 592 if (parent.get()) { 593 parent->SetNextAddress(entry_address); 594 } else { 595 data_->table[hash & mask_] = entry_address.value(); 596 } 597 598 // Link this entry through the lists. 599 eviction_.OnCreateEntry(cache_entry.get()); 600 601 CACHE_UMA(AGE_MS, "CreateTime", 0, start); 602 stats_.OnEvent(Stats::CREATE_HIT); 603 SIMPLE_STATS_COUNTER("disk_cache.miss"); 604 Trace("create entry hit "); 605 FlushIndex(); 606 cache_entry->AddRef(); 607 return cache_entry.get(); 608} 609 610EntryImpl* BackendImpl::OpenNextEntryImpl(void** iter) { 611 return OpenFollowingEntry(true, iter); 612} 613 614EntryImpl* BackendImpl::OpenPrevEntryImpl(void** iter) { 615 return OpenFollowingEntry(false, iter); 616} 617 618bool BackendImpl::SetMaxSize(int max_bytes) { 619 COMPILE_ASSERT(sizeof(max_bytes) == sizeof(max_size_), unsupported_int_model); 620 if (max_bytes < 0) 621 return false; 622 623 // Zero size means use the default. 624 if (!max_bytes) 625 return true; 626 627 // Avoid a DCHECK later on. 628 if (max_bytes >= kint32max - kint32max / 10) 629 max_bytes = kint32max - kint32max / 10 - 1; 630 631 user_flags_ |= kMaxSize; 632 max_size_ = max_bytes; 633 return true; 634} 635 636void BackendImpl::SetType(net::CacheType type) { 637 DCHECK_NE(net::MEMORY_CACHE, type); 638 cache_type_ = type; 639} 640 641base::FilePath BackendImpl::GetFileName(Addr address) const { 642 if (!address.is_separate_file() || !address.is_initialized()) { 643 NOTREACHED(); 644 return base::FilePath(); 645 } 646 647 std::string tmp = base::StringPrintf("f_%06x", address.FileNumber()); 648 return path_.AppendASCII(tmp); 649} 650 651MappedFile* BackendImpl::File(Addr address) { 652 if (disabled_) 653 return NULL; 654 return block_files_.GetFile(address); 655} 656 657base::WeakPtr<InFlightBackendIO> BackendImpl::GetBackgroundQueue() { 658 return background_queue_.GetWeakPtr(); 659} 660 661bool BackendImpl::CreateExternalFile(Addr* address) { 662 int file_number = data_->header.last_file + 1; 663 Addr file_address(0); 664 bool success = false; 665 for (int i = 0; i < 0x0fffffff; i++, file_number++) { 666 if (!file_address.SetFileNumber(file_number)) { 667 file_number = 1; 668 continue; 669 } 670 base::FilePath name = GetFileName(file_address); 671 int flags = base::PLATFORM_FILE_READ | 672 base::PLATFORM_FILE_WRITE | 673 base::PLATFORM_FILE_CREATE | 674 base::PLATFORM_FILE_EXCLUSIVE_WRITE; 675 base::PlatformFileError error; 676 scoped_refptr<disk_cache::File> file(new disk_cache::File( 677 base::CreatePlatformFile(name, flags, NULL, &error))); 678 if (!file->IsValid()) { 679 if (error != base::PLATFORM_FILE_ERROR_EXISTS) { 680 LOG(ERROR) << "Unable to create file: " << error; 681 return false; 682 } 683 continue; 684 } 685 686 success = true; 687 break; 688 } 689 690 DCHECK(success); 691 if (!success) 692 return false; 693 694 data_->header.last_file = file_number; 695 address->set_value(file_address.value()); 696 return true; 697} 698 699bool BackendImpl::CreateBlock(FileType block_type, int block_count, 700 Addr* block_address) { 701 return block_files_.CreateBlock(block_type, block_count, block_address); 702} 703 704void BackendImpl::DeleteBlock(Addr block_address, bool deep) { 705 block_files_.DeleteBlock(block_address, deep); 706} 707 708LruData* BackendImpl::GetLruData() { 709 return &data_->header.lru; 710} 711 712void BackendImpl::UpdateRank(EntryImpl* entry, bool modified) { 713 if (read_only_ || (!modified && cache_type() == net::SHADER_CACHE)) 714 return; 715 eviction_.UpdateRank(entry, modified); 716} 717 718void BackendImpl::RecoveredEntry(CacheRankingsBlock* rankings) { 719 Addr address(rankings->Data()->contents); 720 EntryImpl* cache_entry = NULL; 721 if (NewEntry(address, &cache_entry)) { 722 STRESS_NOTREACHED(); 723 return; 724 } 725 726 uint32 hash = cache_entry->GetHash(); 727 cache_entry->Release(); 728 729 // Anything on the table means that this entry is there. 730 if (data_->table[hash & mask_]) 731 return; 732 733 data_->table[hash & mask_] = address.value(); 734 FlushIndex(); 735} 736 737void BackendImpl::InternalDoomEntry(EntryImpl* entry) { 738 uint32 hash = entry->GetHash(); 739 std::string key = entry->GetKey(); 740 Addr entry_addr = entry->entry()->address(); 741 bool error; 742 EntryImpl* parent_entry = MatchEntry(key, hash, true, entry_addr, &error); 743 CacheAddr child(entry->GetNextAddress()); 744 745 Trace("Doom entry 0x%p", entry); 746 747 if (!entry->doomed()) { 748 // We may have doomed this entry from within MatchEntry. 749 eviction_.OnDoomEntry(entry); 750 entry->InternalDoom(); 751 if (!new_eviction_) { 752 DecreaseNumEntries(); 753 } 754 stats_.OnEvent(Stats::DOOM_ENTRY); 755 } 756 757 if (parent_entry) { 758 parent_entry->SetNextAddress(Addr(child)); 759 parent_entry->Release(); 760 } else if (!error) { 761 data_->table[hash & mask_] = child; 762 } 763 764 FlushIndex(); 765} 766 767#if defined(NET_BUILD_STRESS_CACHE) 768 769CacheAddr BackendImpl::GetNextAddr(Addr address) { 770 EntriesMap::iterator it = open_entries_.find(address.value()); 771 if (it != open_entries_.end()) { 772 EntryImpl* this_entry = it->second; 773 return this_entry->GetNextAddress(); 774 } 775 DCHECK(block_files_.IsValid(address)); 776 DCHECK(!address.is_separate_file() && address.file_type() == BLOCK_256); 777 778 CacheEntryBlock entry(File(address), address); 779 CHECK(entry.Load()); 780 return entry.Data()->next; 781} 782 783void BackendImpl::NotLinked(EntryImpl* entry) { 784 Addr entry_addr = entry->entry()->address(); 785 uint32 i = entry->GetHash() & mask_; 786 Addr address(data_->table[i]); 787 if (!address.is_initialized()) 788 return; 789 790 for (;;) { 791 DCHECK(entry_addr.value() != address.value()); 792 address.set_value(GetNextAddr(address)); 793 if (!address.is_initialized()) 794 break; 795 } 796} 797#endif // NET_BUILD_STRESS_CACHE 798 799// An entry may be linked on the DELETED list for a while after being doomed. 800// This function is called when we want to remove it. 801void BackendImpl::RemoveEntry(EntryImpl* entry) { 802#if defined(NET_BUILD_STRESS_CACHE) 803 NotLinked(entry); 804#endif 805 if (!new_eviction_) 806 return; 807 808 DCHECK_NE(ENTRY_NORMAL, entry->entry()->Data()->state); 809 810 Trace("Remove entry 0x%p", entry); 811 eviction_.OnDestroyEntry(entry); 812 DecreaseNumEntries(); 813} 814 815void BackendImpl::OnEntryDestroyBegin(Addr address) { 816 EntriesMap::iterator it = open_entries_.find(address.value()); 817 if (it != open_entries_.end()) 818 open_entries_.erase(it); 819} 820 821void BackendImpl::OnEntryDestroyEnd() { 822 DecreaseNumRefs(); 823 if (data_->header.num_bytes > max_size_ && !read_only_ && 824 (up_ticks_ > kTrimDelay || user_flags_ & kNoRandom)) 825 eviction_.TrimCache(false); 826} 827 828EntryImpl* BackendImpl::GetOpenEntry(CacheRankingsBlock* rankings) const { 829 DCHECK(rankings->HasData()); 830 EntriesMap::const_iterator it = 831 open_entries_.find(rankings->Data()->contents); 832 if (it != open_entries_.end()) { 833 // We have this entry in memory. 834 return it->second; 835 } 836 837 return NULL; 838} 839 840int32 BackendImpl::GetCurrentEntryId() const { 841 return data_->header.this_id; 842} 843 844int BackendImpl::MaxFileSize() const { 845 return cache_type() == net::PNACL_CACHE ? max_size_ : max_size_ / 8; 846} 847 848void BackendImpl::ModifyStorageSize(int32 old_size, int32 new_size) { 849 if (disabled_ || old_size == new_size) 850 return; 851 if (old_size > new_size) 852 SubstractStorageSize(old_size - new_size); 853 else 854 AddStorageSize(new_size - old_size); 855 856 FlushIndex(); 857 858 // Update the usage statistics. 859 stats_.ModifyStorageStats(old_size, new_size); 860} 861 862void BackendImpl::TooMuchStorageRequested(int32 size) { 863 stats_.ModifyStorageStats(0, size); 864} 865 866bool BackendImpl::IsAllocAllowed(int current_size, int new_size) { 867 DCHECK_GT(new_size, current_size); 868 if (user_flags_ & kNoBuffering) 869 return false; 870 871 int to_add = new_size - current_size; 872 if (buffer_bytes_ + to_add > MaxBuffersSize()) 873 return false; 874 875 buffer_bytes_ += to_add; 876 CACHE_UMA(COUNTS_50000, "BufferBytes", 0, buffer_bytes_ / 1024); 877 return true; 878} 879 880void BackendImpl::BufferDeleted(int size) { 881 buffer_bytes_ -= size; 882 DCHECK_GE(size, 0); 883} 884 885bool BackendImpl::IsLoaded() const { 886 CACHE_UMA(COUNTS, "PendingIO", 0, num_pending_io_); 887 if (user_flags_ & kNoLoadProtection) 888 return false; 889 890 return (num_pending_io_ > 5 || user_load_); 891} 892 893std::string BackendImpl::HistogramName(const char* name, int experiment) const { 894 if (!experiment) 895 return base::StringPrintf("DiskCache.%d.%s", cache_type_, name); 896 return base::StringPrintf("DiskCache.%d.%s_%d", cache_type_, 897 name, experiment); 898} 899 900base::WeakPtr<BackendImpl> BackendImpl::GetWeakPtr() { 901 return ptr_factory_.GetWeakPtr(); 902} 903 904// We want to remove biases from some histograms so we only send data once per 905// week. 906bool BackendImpl::ShouldReportAgain() { 907 if (uma_report_) 908 return uma_report_ == 2; 909 910 uma_report_++; 911 int64 last_report = stats_.GetCounter(Stats::LAST_REPORT); 912 Time last_time = Time::FromInternalValue(last_report); 913 if (!last_report || (Time::Now() - last_time).InDays() >= 7) { 914 stats_.SetCounter(Stats::LAST_REPORT, Time::Now().ToInternalValue()); 915 uma_report_++; 916 return true; 917 } 918 return false; 919} 920 921void BackendImpl::FirstEviction() { 922 DCHECK(data_->header.create_time); 923 if (!GetEntryCount()) 924 return; // This is just for unit tests. 925 926 Time create_time = Time::FromInternalValue(data_->header.create_time); 927 CACHE_UMA(AGE, "FillupAge", 0, create_time); 928 929 int64 use_time = stats_.GetCounter(Stats::TIMER); 930 CACHE_UMA(HOURS, "FillupTime", 0, static_cast<int>(use_time / 120)); 931 CACHE_UMA(PERCENTAGE, "FirstHitRatio", 0, stats_.GetHitRatio()); 932 933 if (!use_time) 934 use_time = 1; 935 CACHE_UMA(COUNTS_10000, "FirstEntryAccessRate", 0, 936 static_cast<int>(data_->header.num_entries / use_time)); 937 CACHE_UMA(COUNTS, "FirstByteIORate", 0, 938 static_cast<int>((data_->header.num_bytes / 1024) / use_time)); 939 940 int avg_size = data_->header.num_bytes / GetEntryCount(); 941 CACHE_UMA(COUNTS, "FirstEntrySize", 0, avg_size); 942 943 int large_entries_bytes = stats_.GetLargeEntriesSize(); 944 int large_ratio = large_entries_bytes * 100 / data_->header.num_bytes; 945 CACHE_UMA(PERCENTAGE, "FirstLargeEntriesRatio", 0, large_ratio); 946 947 if (new_eviction_) { 948 CACHE_UMA(PERCENTAGE, "FirstResurrectRatio", 0, stats_.GetResurrectRatio()); 949 CACHE_UMA(PERCENTAGE, "FirstNoUseRatio", 0, 950 data_->header.lru.sizes[0] * 100 / data_->header.num_entries); 951 CACHE_UMA(PERCENTAGE, "FirstLowUseRatio", 0, 952 data_->header.lru.sizes[1] * 100 / data_->header.num_entries); 953 CACHE_UMA(PERCENTAGE, "FirstHighUseRatio", 0, 954 data_->header.lru.sizes[2] * 100 / data_->header.num_entries); 955 } 956 957 stats_.ResetRatios(); 958} 959 960void BackendImpl::CriticalError(int error) { 961 STRESS_NOTREACHED(); 962 LOG(ERROR) << "Critical error found " << error; 963 if (disabled_) 964 return; 965 966 stats_.OnEvent(Stats::FATAL_ERROR); 967 LogStats(); 968 ReportError(error); 969 970 // Setting the index table length to an invalid value will force re-creation 971 // of the cache files. 972 data_->header.table_len = 1; 973 disabled_ = true; 974 975 if (!num_refs_) 976 base::MessageLoop::current()->PostTask( 977 FROM_HERE, base::Bind(&BackendImpl::RestartCache, GetWeakPtr(), true)); 978} 979 980void BackendImpl::ReportError(int error) { 981 STRESS_DCHECK(!error || error == ERR_PREVIOUS_CRASH || 982 error == ERR_CACHE_CREATED); 983 984 // We transmit positive numbers, instead of direct error codes. 985 DCHECK_LE(error, 0); 986 CACHE_UMA(CACHE_ERROR, "Error", 0, error * -1); 987} 988 989void BackendImpl::OnEvent(Stats::Counters an_event) { 990 stats_.OnEvent(an_event); 991} 992 993void BackendImpl::OnRead(int32 bytes) { 994 DCHECK_GE(bytes, 0); 995 byte_count_ += bytes; 996 if (byte_count_ < 0) 997 byte_count_ = kint32max; 998} 999 1000void BackendImpl::OnWrite(int32 bytes) { 1001 // We use the same implementation as OnRead... just log the number of bytes. 1002 OnRead(bytes); 1003} 1004 1005void BackendImpl::OnStatsTimer() { 1006 if (disabled_) 1007 return; 1008 1009 stats_.OnEvent(Stats::TIMER); 1010 int64 time = stats_.GetCounter(Stats::TIMER); 1011 int64 current = stats_.GetCounter(Stats::OPEN_ENTRIES); 1012 1013 // OPEN_ENTRIES is a sampled average of the number of open entries, avoiding 1014 // the bias towards 0. 1015 if (num_refs_ && (current != num_refs_)) { 1016 int64 diff = (num_refs_ - current) / 50; 1017 if (!diff) 1018 diff = num_refs_ > current ? 1 : -1; 1019 current = current + diff; 1020 stats_.SetCounter(Stats::OPEN_ENTRIES, current); 1021 stats_.SetCounter(Stats::MAX_ENTRIES, max_refs_); 1022 } 1023 1024 CACHE_UMA(COUNTS, "NumberOfReferences", 0, num_refs_); 1025 1026 CACHE_UMA(COUNTS_10000, "EntryAccessRate", 0, entry_count_); 1027 CACHE_UMA(COUNTS, "ByteIORate", 0, byte_count_ / 1024); 1028 1029 // These values cover about 99.5% of the population (Oct 2011). 1030 user_load_ = (entry_count_ > 300 || byte_count_ > 7 * 1024 * 1024); 1031 entry_count_ = 0; 1032 byte_count_ = 0; 1033 up_ticks_++; 1034 1035 if (!data_) 1036 first_timer_ = false; 1037 if (first_timer_) { 1038 first_timer_ = false; 1039 if (ShouldReportAgain()) 1040 ReportStats(); 1041 } 1042 1043 // Save stats to disk at 5 min intervals. 1044 if (time % 10 == 0) 1045 StoreStats(); 1046} 1047 1048void BackendImpl::IncrementIoCount() { 1049 num_pending_io_++; 1050} 1051 1052void BackendImpl::DecrementIoCount() { 1053 num_pending_io_--; 1054} 1055 1056void BackendImpl::SetUnitTestMode() { 1057 user_flags_ |= kUnitTestMode; 1058 unit_test_ = true; 1059} 1060 1061void BackendImpl::SetUpgradeMode() { 1062 user_flags_ |= kUpgradeMode; 1063 read_only_ = true; 1064} 1065 1066void BackendImpl::SetNewEviction() { 1067 user_flags_ |= kNewEviction; 1068 new_eviction_ = true; 1069} 1070 1071void BackendImpl::SetFlags(uint32 flags) { 1072 user_flags_ |= flags; 1073} 1074 1075void BackendImpl::ClearRefCountForTest() { 1076 num_refs_ = 0; 1077} 1078 1079int BackendImpl::FlushQueueForTest(const CompletionCallback& callback) { 1080 background_queue_.FlushQueue(callback); 1081 return net::ERR_IO_PENDING; 1082} 1083 1084int BackendImpl::RunTaskForTest(const base::Closure& task, 1085 const CompletionCallback& callback) { 1086 background_queue_.RunTask(task, callback); 1087 return net::ERR_IO_PENDING; 1088} 1089 1090void BackendImpl::TrimForTest(bool empty) { 1091 eviction_.SetTestMode(); 1092 eviction_.TrimCache(empty); 1093} 1094 1095void BackendImpl::TrimDeletedListForTest(bool empty) { 1096 eviction_.SetTestMode(); 1097 eviction_.TrimDeletedList(empty); 1098} 1099 1100base::RepeatingTimer<BackendImpl>* BackendImpl::GetTimerForTest() { 1101 return timer_.get(); 1102} 1103 1104int BackendImpl::SelfCheck() { 1105 if (!init_) { 1106 LOG(ERROR) << "Init failed"; 1107 return ERR_INIT_FAILED; 1108 } 1109 1110 int num_entries = rankings_.SelfCheck(); 1111 if (num_entries < 0) { 1112 LOG(ERROR) << "Invalid rankings list, error " << num_entries; 1113#if !defined(NET_BUILD_STRESS_CACHE) 1114 return num_entries; 1115#endif 1116 } 1117 1118 if (num_entries != data_->header.num_entries) { 1119 LOG(ERROR) << "Number of entries mismatch"; 1120#if !defined(NET_BUILD_STRESS_CACHE) 1121 return ERR_NUM_ENTRIES_MISMATCH; 1122#endif 1123 } 1124 1125 return CheckAllEntries(); 1126} 1127 1128void BackendImpl::FlushIndex() { 1129 if (index_.get() && !disabled_) 1130 index_->Flush(); 1131} 1132 1133// ------------------------------------------------------------------------ 1134 1135net::CacheType BackendImpl::GetCacheType() const { 1136 return cache_type_; 1137} 1138 1139int32 BackendImpl::GetEntryCount() const { 1140 if (!index_.get() || disabled_) 1141 return 0; 1142 // num_entries includes entries already evicted. 1143 int32 not_deleted = data_->header.num_entries - 1144 data_->header.lru.sizes[Rankings::DELETED]; 1145 1146 if (not_deleted < 0) { 1147 NOTREACHED(); 1148 not_deleted = 0; 1149 } 1150 1151 return not_deleted; 1152} 1153 1154int BackendImpl::OpenEntry(const std::string& key, Entry** entry, 1155 const CompletionCallback& callback) { 1156 DCHECK(!callback.is_null()); 1157 background_queue_.OpenEntry(key, entry, callback); 1158 return net::ERR_IO_PENDING; 1159} 1160 1161int BackendImpl::CreateEntry(const std::string& key, Entry** entry, 1162 const CompletionCallback& callback) { 1163 DCHECK(!callback.is_null()); 1164 background_queue_.CreateEntry(key, entry, callback); 1165 return net::ERR_IO_PENDING; 1166} 1167 1168int BackendImpl::DoomEntry(const std::string& key, 1169 const CompletionCallback& callback) { 1170 DCHECK(!callback.is_null()); 1171 background_queue_.DoomEntry(key, callback); 1172 return net::ERR_IO_PENDING; 1173} 1174 1175int BackendImpl::DoomAllEntries(const CompletionCallback& callback) { 1176 DCHECK(!callback.is_null()); 1177 background_queue_.DoomAllEntries(callback); 1178 return net::ERR_IO_PENDING; 1179} 1180 1181int BackendImpl::DoomEntriesBetween(const base::Time initial_time, 1182 const base::Time end_time, 1183 const CompletionCallback& callback) { 1184 DCHECK(!callback.is_null()); 1185 background_queue_.DoomEntriesBetween(initial_time, end_time, callback); 1186 return net::ERR_IO_PENDING; 1187} 1188 1189int BackendImpl::DoomEntriesSince(const base::Time initial_time, 1190 const CompletionCallback& callback) { 1191 DCHECK(!callback.is_null()); 1192 background_queue_.DoomEntriesSince(initial_time, callback); 1193 return net::ERR_IO_PENDING; 1194} 1195 1196int BackendImpl::OpenNextEntry(void** iter, Entry** next_entry, 1197 const CompletionCallback& callback) { 1198 DCHECK(!callback.is_null()); 1199 background_queue_.OpenNextEntry(iter, next_entry, callback); 1200 return net::ERR_IO_PENDING; 1201} 1202 1203void BackendImpl::EndEnumeration(void** iter) { 1204 background_queue_.EndEnumeration(*iter); 1205 *iter = NULL; 1206} 1207 1208void BackendImpl::GetStats(StatsItems* stats) { 1209 if (disabled_) 1210 return; 1211 1212 std::pair<std::string, std::string> item; 1213 1214 item.first = "Entries"; 1215 item.second = base::StringPrintf("%d", data_->header.num_entries); 1216 stats->push_back(item); 1217 1218 item.first = "Pending IO"; 1219 item.second = base::StringPrintf("%d", num_pending_io_); 1220 stats->push_back(item); 1221 1222 item.first = "Max size"; 1223 item.second = base::StringPrintf("%d", max_size_); 1224 stats->push_back(item); 1225 1226 item.first = "Current size"; 1227 item.second = base::StringPrintf("%d", data_->header.num_bytes); 1228 stats->push_back(item); 1229 1230 item.first = "Cache type"; 1231 item.second = "Blockfile Cache"; 1232 stats->push_back(item); 1233 1234 stats_.GetItems(stats); 1235} 1236 1237void BackendImpl::OnExternalCacheHit(const std::string& key) { 1238 background_queue_.OnExternalCacheHit(key); 1239} 1240 1241// ------------------------------------------------------------------------ 1242 1243// We just created a new file so we're going to write the header and set the 1244// file length to include the hash table (zero filled). 1245bool BackendImpl::CreateBackingStore(disk_cache::File* file) { 1246 AdjustMaxCacheSize(0); 1247 1248 IndexHeader header; 1249 header.table_len = DesiredIndexTableLen(max_size_); 1250 1251 // We need file version 2.1 for the new eviction algorithm. 1252 if (new_eviction_) 1253 header.version = 0x20001; 1254 1255 header.create_time = Time::Now().ToInternalValue(); 1256 1257 if (!file->Write(&header, sizeof(header), 0)) 1258 return false; 1259 1260 return file->SetLength(GetIndexSize(header.table_len)); 1261} 1262 1263bool BackendImpl::InitBackingStore(bool* file_created) { 1264 if (!base::CreateDirectory(path_)) 1265 return false; 1266 1267 base::FilePath index_name = path_.AppendASCII(kIndexName); 1268 1269 int flags = base::PLATFORM_FILE_READ | 1270 base::PLATFORM_FILE_WRITE | 1271 base::PLATFORM_FILE_OPEN_ALWAYS | 1272 base::PLATFORM_FILE_EXCLUSIVE_WRITE; 1273 scoped_refptr<disk_cache::File> file(new disk_cache::File( 1274 base::CreatePlatformFile(index_name, flags, file_created, NULL))); 1275 1276 if (!file->IsValid()) 1277 return false; 1278 1279 bool ret = true; 1280 if (*file_created) 1281 ret = CreateBackingStore(file.get()); 1282 1283 file = NULL; 1284 if (!ret) 1285 return false; 1286 1287 index_ = new MappedFile(); 1288 data_ = static_cast<Index*>(index_->Init(index_name, 0)); 1289 if (!data_) { 1290 LOG(ERROR) << "Unable to map Index file"; 1291 return false; 1292 } 1293 1294 if (index_->GetLength() < sizeof(Index)) { 1295 // We verify this again on CheckIndex() but it's easier to make sure now 1296 // that the header is there. 1297 LOG(ERROR) << "Corrupt Index file"; 1298 return false; 1299 } 1300 1301 return true; 1302} 1303 1304// The maximum cache size will be either set explicitly by the caller, or 1305// calculated by this code. 1306void BackendImpl::AdjustMaxCacheSize(int table_len) { 1307 if (max_size_) 1308 return; 1309 1310 // If table_len is provided, the index file exists. 1311 DCHECK(!table_len || data_->header.magic); 1312 1313 // The user is not setting the size, let's figure it out. 1314 int64 available = base::SysInfo::AmountOfFreeDiskSpace(path_); 1315 if (available < 0) { 1316 max_size_ = kDefaultCacheSize; 1317 return; 1318 } 1319 1320 if (table_len) 1321 available += data_->header.num_bytes; 1322 1323 max_size_ = PreferredCacheSize(available); 1324 1325 if (!table_len) 1326 return; 1327 1328 // If we already have a table, adjust the size to it. 1329 int current_max_size = MaxStorageSizeForTable(table_len); 1330 if (max_size_ > current_max_size) 1331 max_size_= current_max_size; 1332} 1333 1334bool BackendImpl::InitStats() { 1335 Addr address(data_->header.stats); 1336 int size = stats_.StorageSize(); 1337 1338 if (!address.is_initialized()) { 1339 FileType file_type = Addr::RequiredFileType(size); 1340 DCHECK_NE(file_type, EXTERNAL); 1341 int num_blocks = Addr::RequiredBlocks(size, file_type); 1342 1343 if (!CreateBlock(file_type, num_blocks, &address)) 1344 return false; 1345 1346 data_->header.stats = address.value(); 1347 return stats_.Init(NULL, 0, address); 1348 } 1349 1350 if (!address.is_block_file()) { 1351 NOTREACHED(); 1352 return false; 1353 } 1354 1355 // Load the required data. 1356 size = address.num_blocks() * address.BlockSize(); 1357 MappedFile* file = File(address); 1358 if (!file) 1359 return false; 1360 1361 scoped_ptr<char[]> data(new char[size]); 1362 size_t offset = address.start_block() * address.BlockSize() + 1363 kBlockHeaderSize; 1364 if (!file->Read(data.get(), size, offset)) 1365 return false; 1366 1367 if (!stats_.Init(data.get(), size, address)) 1368 return false; 1369 if (cache_type_ == net::DISK_CACHE && ShouldReportAgain()) 1370 stats_.InitSizeHistogram(); 1371 return true; 1372} 1373 1374void BackendImpl::StoreStats() { 1375 int size = stats_.StorageSize(); 1376 scoped_ptr<char[]> data(new char[size]); 1377 Addr address; 1378 size = stats_.SerializeStats(data.get(), size, &address); 1379 DCHECK(size); 1380 if (!address.is_initialized()) 1381 return; 1382 1383 MappedFile* file = File(address); 1384 if (!file) 1385 return; 1386 1387 size_t offset = address.start_block() * address.BlockSize() + 1388 kBlockHeaderSize; 1389 file->Write(data.get(), size, offset); // ignore result. 1390} 1391 1392void BackendImpl::RestartCache(bool failure) { 1393 int64 errors = stats_.GetCounter(Stats::FATAL_ERROR); 1394 int64 full_dooms = stats_.GetCounter(Stats::DOOM_CACHE); 1395 int64 partial_dooms = stats_.GetCounter(Stats::DOOM_RECENT); 1396 int64 last_report = stats_.GetCounter(Stats::LAST_REPORT); 1397 1398 PrepareForRestart(); 1399 if (failure) { 1400 DCHECK(!num_refs_); 1401 DCHECK(!open_entries_.size()); 1402 DelayedCacheCleanup(path_); 1403 } else { 1404 DeleteCache(path_, false); 1405 } 1406 1407 // Don't call Init() if directed by the unit test: we are simulating a failure 1408 // trying to re-enable the cache. 1409 if (unit_test_) 1410 init_ = true; // Let the destructor do proper cleanup. 1411 else if (SyncInit() == net::OK) { 1412 stats_.SetCounter(Stats::FATAL_ERROR, errors); 1413 stats_.SetCounter(Stats::DOOM_CACHE, full_dooms); 1414 stats_.SetCounter(Stats::DOOM_RECENT, partial_dooms); 1415 stats_.SetCounter(Stats::LAST_REPORT, last_report); 1416 } 1417} 1418 1419void BackendImpl::PrepareForRestart() { 1420 // Reset the mask_ if it was not given by the user. 1421 if (!(user_flags_ & kMask)) 1422 mask_ = 0; 1423 1424 if (!(user_flags_ & kNewEviction)) 1425 new_eviction_ = false; 1426 1427 disabled_ = true; 1428 data_->header.crash = 0; 1429 index_->Flush(); 1430 index_ = NULL; 1431 data_ = NULL; 1432 block_files_.CloseFiles(); 1433 rankings_.Reset(); 1434 init_ = false; 1435 restarted_ = true; 1436} 1437 1438int BackendImpl::NewEntry(Addr address, EntryImpl** entry) { 1439 EntriesMap::iterator it = open_entries_.find(address.value()); 1440 if (it != open_entries_.end()) { 1441 // Easy job. This entry is already in memory. 1442 EntryImpl* this_entry = it->second; 1443 this_entry->AddRef(); 1444 *entry = this_entry; 1445 return 0; 1446 } 1447 1448 STRESS_DCHECK(block_files_.IsValid(address)); 1449 1450 if (!address.SanityCheckForEntryV2()) { 1451 LOG(WARNING) << "Wrong entry address."; 1452 STRESS_NOTREACHED(); 1453 return ERR_INVALID_ADDRESS; 1454 } 1455 1456 scoped_refptr<EntryImpl> cache_entry( 1457 new EntryImpl(this, address, read_only_)); 1458 IncreaseNumRefs(); 1459 *entry = NULL; 1460 1461 TimeTicks start = TimeTicks::Now(); 1462 if (!cache_entry->entry()->Load()) 1463 return ERR_READ_FAILURE; 1464 1465 if (IsLoaded()) { 1466 CACHE_UMA(AGE_MS, "LoadTime", 0, start); 1467 } 1468 1469 if (!cache_entry->SanityCheck()) { 1470 LOG(WARNING) << "Messed up entry found."; 1471 STRESS_NOTREACHED(); 1472 return ERR_INVALID_ENTRY; 1473 } 1474 1475 STRESS_DCHECK(block_files_.IsValid( 1476 Addr(cache_entry->entry()->Data()->rankings_node))); 1477 1478 if (!cache_entry->LoadNodeAddress()) 1479 return ERR_READ_FAILURE; 1480 1481 if (!rankings_.SanityCheck(cache_entry->rankings(), false)) { 1482 STRESS_NOTREACHED(); 1483 cache_entry->SetDirtyFlag(0); 1484 // Don't remove this from the list (it is not linked properly). Instead, 1485 // break the link back to the entry because it is going away, and leave the 1486 // rankings node to be deleted if we find it through a list. 1487 rankings_.SetContents(cache_entry->rankings(), 0); 1488 } else if (!rankings_.DataSanityCheck(cache_entry->rankings(), false)) { 1489 STRESS_NOTREACHED(); 1490 cache_entry->SetDirtyFlag(0); 1491 rankings_.SetContents(cache_entry->rankings(), address.value()); 1492 } 1493 1494 if (!cache_entry->DataSanityCheck()) { 1495 LOG(WARNING) << "Messed up entry found."; 1496 cache_entry->SetDirtyFlag(0); 1497 cache_entry->FixForDelete(); 1498 } 1499 1500 // Prevent overwriting the dirty flag on the destructor. 1501 cache_entry->SetDirtyFlag(GetCurrentEntryId()); 1502 1503 if (cache_entry->dirty()) { 1504 Trace("Dirty entry 0x%p 0x%x", reinterpret_cast<void*>(cache_entry.get()), 1505 address.value()); 1506 } 1507 1508 open_entries_[address.value()] = cache_entry.get(); 1509 1510 cache_entry->BeginLogging(net_log_, false); 1511 cache_entry.swap(entry); 1512 return 0; 1513} 1514 1515EntryImpl* BackendImpl::MatchEntry(const std::string& key, uint32 hash, 1516 bool find_parent, Addr entry_addr, 1517 bool* match_error) { 1518 Addr address(data_->table[hash & mask_]); 1519 scoped_refptr<EntryImpl> cache_entry, parent_entry; 1520 EntryImpl* tmp = NULL; 1521 bool found = false; 1522 std::set<CacheAddr> visited; 1523 *match_error = false; 1524 1525 for (;;) { 1526 if (disabled_) 1527 break; 1528 1529 if (visited.find(address.value()) != visited.end()) { 1530 // It's possible for a buggy version of the code to write a loop. Just 1531 // break it. 1532 Trace("Hash collision loop 0x%x", address.value()); 1533 address.set_value(0); 1534 parent_entry->SetNextAddress(address); 1535 } 1536 visited.insert(address.value()); 1537 1538 if (!address.is_initialized()) { 1539 if (find_parent) 1540 found = true; 1541 break; 1542 } 1543 1544 int error = NewEntry(address, &tmp); 1545 cache_entry.swap(&tmp); 1546 1547 if (error || cache_entry->dirty()) { 1548 // This entry is dirty on disk (it was not properly closed): we cannot 1549 // trust it. 1550 Addr child(0); 1551 if (!error) 1552 child.set_value(cache_entry->GetNextAddress()); 1553 1554 if (parent_entry.get()) { 1555 parent_entry->SetNextAddress(child); 1556 parent_entry = NULL; 1557 } else { 1558 data_->table[hash & mask_] = child.value(); 1559 } 1560 1561 Trace("MatchEntry dirty %d 0x%x 0x%x", find_parent, entry_addr.value(), 1562 address.value()); 1563 1564 if (!error) { 1565 // It is important to call DestroyInvalidEntry after removing this 1566 // entry from the table. 1567 DestroyInvalidEntry(cache_entry.get()); 1568 cache_entry = NULL; 1569 } else { 1570 Trace("NewEntry failed on MatchEntry 0x%x", address.value()); 1571 } 1572 1573 // Restart the search. 1574 address.set_value(data_->table[hash & mask_]); 1575 visited.clear(); 1576 continue; 1577 } 1578 1579 DCHECK_EQ(hash & mask_, cache_entry->entry()->Data()->hash & mask_); 1580 if (cache_entry->IsSameEntry(key, hash)) { 1581 if (!cache_entry->Update()) 1582 cache_entry = NULL; 1583 found = true; 1584 if (find_parent && entry_addr.value() != address.value()) { 1585 Trace("Entry not on the index 0x%x", address.value()); 1586 *match_error = true; 1587 parent_entry = NULL; 1588 } 1589 break; 1590 } 1591 if (!cache_entry->Update()) 1592 cache_entry = NULL; 1593 parent_entry = cache_entry; 1594 cache_entry = NULL; 1595 if (!parent_entry.get()) 1596 break; 1597 1598 address.set_value(parent_entry->GetNextAddress()); 1599 } 1600 1601 if (parent_entry.get() && (!find_parent || !found)) 1602 parent_entry = NULL; 1603 1604 if (find_parent && entry_addr.is_initialized() && !cache_entry.get()) { 1605 *match_error = true; 1606 parent_entry = NULL; 1607 } 1608 1609 if (cache_entry.get() && (find_parent || !found)) 1610 cache_entry = NULL; 1611 1612 find_parent ? parent_entry.swap(&tmp) : cache_entry.swap(&tmp); 1613 FlushIndex(); 1614 return tmp; 1615} 1616 1617// This is the actual implementation for OpenNextEntry and OpenPrevEntry. 1618EntryImpl* BackendImpl::OpenFollowingEntry(bool forward, void** iter) { 1619 if (disabled_) 1620 return NULL; 1621 1622 DCHECK(iter); 1623 1624 const int kListsToSearch = 3; 1625 scoped_refptr<EntryImpl> entries[kListsToSearch]; 1626 scoped_ptr<Rankings::Iterator> iterator( 1627 reinterpret_cast<Rankings::Iterator*>(*iter)); 1628 *iter = NULL; 1629 1630 if (!iterator.get()) { 1631 iterator.reset(new Rankings::Iterator(&rankings_)); 1632 bool ret = false; 1633 1634 // Get an entry from each list. 1635 for (int i = 0; i < kListsToSearch; i++) { 1636 EntryImpl* temp = NULL; 1637 ret |= OpenFollowingEntryFromList(forward, static_cast<Rankings::List>(i), 1638 &iterator->nodes[i], &temp); 1639 entries[i].swap(&temp); // The entry was already addref'd. 1640 } 1641 if (!ret) 1642 return NULL; 1643 } else { 1644 // Get the next entry from the last list, and the actual entries for the 1645 // elements on the other lists. 1646 for (int i = 0; i < kListsToSearch; i++) { 1647 EntryImpl* temp = NULL; 1648 if (iterator->list == i) { 1649 OpenFollowingEntryFromList(forward, iterator->list, 1650 &iterator->nodes[i], &temp); 1651 } else { 1652 temp = GetEnumeratedEntry(iterator->nodes[i], 1653 static_cast<Rankings::List>(i)); 1654 } 1655 1656 entries[i].swap(&temp); // The entry was already addref'd. 1657 } 1658 } 1659 1660 int newest = -1; 1661 int oldest = -1; 1662 Time access_times[kListsToSearch]; 1663 for (int i = 0; i < kListsToSearch; i++) { 1664 if (entries[i].get()) { 1665 access_times[i] = entries[i]->GetLastUsed(); 1666 if (newest < 0) { 1667 DCHECK_LT(oldest, 0); 1668 newest = oldest = i; 1669 continue; 1670 } 1671 if (access_times[i] > access_times[newest]) 1672 newest = i; 1673 if (access_times[i] < access_times[oldest]) 1674 oldest = i; 1675 } 1676 } 1677 1678 if (newest < 0 || oldest < 0) 1679 return NULL; 1680 1681 EntryImpl* next_entry; 1682 if (forward) { 1683 next_entry = entries[newest].get(); 1684 iterator->list = static_cast<Rankings::List>(newest); 1685 } else { 1686 next_entry = entries[oldest].get(); 1687 iterator->list = static_cast<Rankings::List>(oldest); 1688 } 1689 1690 *iter = iterator.release(); 1691 next_entry->AddRef(); 1692 return next_entry; 1693} 1694 1695bool BackendImpl::OpenFollowingEntryFromList(bool forward, Rankings::List list, 1696 CacheRankingsBlock** from_entry, 1697 EntryImpl** next_entry) { 1698 if (disabled_) 1699 return false; 1700 1701 if (!new_eviction_ && Rankings::NO_USE != list) 1702 return false; 1703 1704 Rankings::ScopedRankingsBlock rankings(&rankings_, *from_entry); 1705 CacheRankingsBlock* next_block = forward ? 1706 rankings_.GetNext(rankings.get(), list) : 1707 rankings_.GetPrev(rankings.get(), list); 1708 Rankings::ScopedRankingsBlock next(&rankings_, next_block); 1709 *from_entry = NULL; 1710 1711 *next_entry = GetEnumeratedEntry(next.get(), list); 1712 if (!*next_entry) 1713 return false; 1714 1715 *from_entry = next.release(); 1716 return true; 1717} 1718 1719EntryImpl* BackendImpl::GetEnumeratedEntry(CacheRankingsBlock* next, 1720 Rankings::List list) { 1721 if (!next || disabled_) 1722 return NULL; 1723 1724 EntryImpl* entry; 1725 int rv = NewEntry(Addr(next->Data()->contents), &entry); 1726 if (rv) { 1727 STRESS_NOTREACHED(); 1728 rankings_.Remove(next, list, false); 1729 if (rv == ERR_INVALID_ADDRESS) { 1730 // There is nothing linked from the index. Delete the rankings node. 1731 DeleteBlock(next->address(), true); 1732 } 1733 return NULL; 1734 } 1735 1736 if (entry->dirty()) { 1737 // We cannot trust this entry. 1738 InternalDoomEntry(entry); 1739 entry->Release(); 1740 return NULL; 1741 } 1742 1743 if (!entry->Update()) { 1744 STRESS_NOTREACHED(); 1745 entry->Release(); 1746 return NULL; 1747 } 1748 1749 // Note that it is unfortunate (but possible) for this entry to be clean, but 1750 // not actually the real entry. In other words, we could have lost this entry 1751 // from the index, and it could have been replaced with a newer one. It's not 1752 // worth checking that this entry is "the real one", so we just return it and 1753 // let the enumeration continue; this entry will be evicted at some point, and 1754 // the regular path will work with the real entry. With time, this problem 1755 // will disasappear because this scenario is just a bug. 1756 1757 // Make sure that we save the key for later. 1758 entry->GetKey(); 1759 1760 return entry; 1761} 1762 1763EntryImpl* BackendImpl::ResurrectEntry(EntryImpl* deleted_entry) { 1764 if (ENTRY_NORMAL == deleted_entry->entry()->Data()->state) { 1765 deleted_entry->Release(); 1766 stats_.OnEvent(Stats::CREATE_MISS); 1767 Trace("create entry miss "); 1768 return NULL; 1769 } 1770 1771 // We are attempting to create an entry and found out that the entry was 1772 // previously deleted. 1773 1774 eviction_.OnCreateEntry(deleted_entry); 1775 entry_count_++; 1776 1777 stats_.OnEvent(Stats::RESURRECT_HIT); 1778 Trace("Resurrect entry hit "); 1779 return deleted_entry; 1780} 1781 1782void BackendImpl::DestroyInvalidEntry(EntryImpl* entry) { 1783 LOG(WARNING) << "Destroying invalid entry."; 1784 Trace("Destroying invalid entry 0x%p", entry); 1785 1786 entry->SetPointerForInvalidEntry(GetCurrentEntryId()); 1787 1788 eviction_.OnDoomEntry(entry); 1789 entry->InternalDoom(); 1790 1791 if (!new_eviction_) 1792 DecreaseNumEntries(); 1793 stats_.OnEvent(Stats::INVALID_ENTRY); 1794} 1795 1796void BackendImpl::AddStorageSize(int32 bytes) { 1797 data_->header.num_bytes += bytes; 1798 DCHECK_GE(data_->header.num_bytes, 0); 1799} 1800 1801void BackendImpl::SubstractStorageSize(int32 bytes) { 1802 data_->header.num_bytes -= bytes; 1803 DCHECK_GE(data_->header.num_bytes, 0); 1804} 1805 1806void BackendImpl::IncreaseNumRefs() { 1807 num_refs_++; 1808 if (max_refs_ < num_refs_) 1809 max_refs_ = num_refs_; 1810} 1811 1812void BackendImpl::DecreaseNumRefs() { 1813 DCHECK(num_refs_); 1814 num_refs_--; 1815 1816 if (!num_refs_ && disabled_) 1817 base::MessageLoop::current()->PostTask( 1818 FROM_HERE, base::Bind(&BackendImpl::RestartCache, GetWeakPtr(), true)); 1819} 1820 1821void BackendImpl::IncreaseNumEntries() { 1822 data_->header.num_entries++; 1823 DCHECK_GT(data_->header.num_entries, 0); 1824} 1825 1826void BackendImpl::DecreaseNumEntries() { 1827 data_->header.num_entries--; 1828 if (data_->header.num_entries < 0) { 1829 NOTREACHED(); 1830 data_->header.num_entries = 0; 1831 } 1832} 1833 1834void BackendImpl::LogStats() { 1835 StatsItems stats; 1836 GetStats(&stats); 1837 1838 for (size_t index = 0; index < stats.size(); index++) 1839 VLOG(1) << stats[index].first << ": " << stats[index].second; 1840} 1841 1842void BackendImpl::ReportStats() { 1843 CACHE_UMA(COUNTS, "Entries", 0, data_->header.num_entries); 1844 1845 int current_size = data_->header.num_bytes / (1024 * 1024); 1846 int max_size = max_size_ / (1024 * 1024); 1847 int hit_ratio_as_percentage = stats_.GetHitRatio(); 1848 1849 CACHE_UMA(COUNTS_10000, "Size2", 0, current_size); 1850 // For any bin in HitRatioBySize2, the hit ratio of caches of that size is the 1851 // ratio of that bin's total count to the count in the same bin in the Size2 1852 // histogram. 1853 if (base::RandInt(0, 99) < hit_ratio_as_percentage) 1854 CACHE_UMA(COUNTS_10000, "HitRatioBySize2", 0, current_size); 1855 CACHE_UMA(COUNTS_10000, "MaxSize2", 0, max_size); 1856 if (!max_size) 1857 max_size++; 1858 CACHE_UMA(PERCENTAGE, "UsedSpace", 0, current_size * 100 / max_size); 1859 1860 CACHE_UMA(COUNTS_10000, "AverageOpenEntries2", 0, 1861 static_cast<int>(stats_.GetCounter(Stats::OPEN_ENTRIES))); 1862 CACHE_UMA(COUNTS_10000, "MaxOpenEntries2", 0, 1863 static_cast<int>(stats_.GetCounter(Stats::MAX_ENTRIES))); 1864 stats_.SetCounter(Stats::MAX_ENTRIES, 0); 1865 1866 CACHE_UMA(COUNTS_10000, "TotalFatalErrors", 0, 1867 static_cast<int>(stats_.GetCounter(Stats::FATAL_ERROR))); 1868 CACHE_UMA(COUNTS_10000, "TotalDoomCache", 0, 1869 static_cast<int>(stats_.GetCounter(Stats::DOOM_CACHE))); 1870 CACHE_UMA(COUNTS_10000, "TotalDoomRecentEntries", 0, 1871 static_cast<int>(stats_.GetCounter(Stats::DOOM_RECENT))); 1872 stats_.SetCounter(Stats::FATAL_ERROR, 0); 1873 stats_.SetCounter(Stats::DOOM_CACHE, 0); 1874 stats_.SetCounter(Stats::DOOM_RECENT, 0); 1875 1876 int age = (Time::Now() - 1877 Time::FromInternalValue(data_->header.create_time)).InHours(); 1878 if (age) 1879 CACHE_UMA(HOURS, "FilesAge", 0, age); 1880 1881 int64 total_hours = stats_.GetCounter(Stats::TIMER) / 120; 1882 if (!data_->header.create_time || !data_->header.lru.filled) { 1883 int cause = data_->header.create_time ? 0 : 1; 1884 if (!data_->header.lru.filled) 1885 cause |= 2; 1886 CACHE_UMA(CACHE_ERROR, "ShortReport", 0, cause); 1887 CACHE_UMA(HOURS, "TotalTimeNotFull", 0, static_cast<int>(total_hours)); 1888 return; 1889 } 1890 1891 // This is an up to date client that will report FirstEviction() data. After 1892 // that event, start reporting this: 1893 1894 CACHE_UMA(HOURS, "TotalTime", 0, static_cast<int>(total_hours)); 1895 // For any bin in HitRatioByTotalTime, the hit ratio of caches of that total 1896 // time is the ratio of that bin's total count to the count in the same bin in 1897 // the TotalTime histogram. 1898 if (base::RandInt(0, 99) < hit_ratio_as_percentage) 1899 CACHE_UMA(HOURS, "HitRatioByTotalTime", 0, implicit_cast<int>(total_hours)); 1900 1901 int64 use_hours = stats_.GetCounter(Stats::LAST_REPORT_TIMER) / 120; 1902 stats_.SetCounter(Stats::LAST_REPORT_TIMER, stats_.GetCounter(Stats::TIMER)); 1903 1904 // We may see users with no use_hours at this point if this is the first time 1905 // we are running this code. 1906 if (use_hours) 1907 use_hours = total_hours - use_hours; 1908 1909 if (!use_hours || !GetEntryCount() || !data_->header.num_bytes) 1910 return; 1911 1912 CACHE_UMA(HOURS, "UseTime", 0, static_cast<int>(use_hours)); 1913 // For any bin in HitRatioByUseTime, the hit ratio of caches of that use time 1914 // is the ratio of that bin's total count to the count in the same bin in the 1915 // UseTime histogram. 1916 if (base::RandInt(0, 99) < hit_ratio_as_percentage) 1917 CACHE_UMA(HOURS, "HitRatioByUseTime", 0, implicit_cast<int>(use_hours)); 1918 CACHE_UMA(PERCENTAGE, "HitRatio", 0, hit_ratio_as_percentage); 1919 1920 int64 trim_rate = stats_.GetCounter(Stats::TRIM_ENTRY) / use_hours; 1921 CACHE_UMA(COUNTS, "TrimRate", 0, static_cast<int>(trim_rate)); 1922 1923 int avg_size = data_->header.num_bytes / GetEntryCount(); 1924 CACHE_UMA(COUNTS, "EntrySize", 0, avg_size); 1925 CACHE_UMA(COUNTS, "EntriesFull", 0, data_->header.num_entries); 1926 1927 CACHE_UMA(PERCENTAGE, "IndexLoad", 0, 1928 data_->header.num_entries * 100 / (mask_ + 1)); 1929 1930 int large_entries_bytes = stats_.GetLargeEntriesSize(); 1931 int large_ratio = large_entries_bytes * 100 / data_->header.num_bytes; 1932 CACHE_UMA(PERCENTAGE, "LargeEntriesRatio", 0, large_ratio); 1933 1934 if (new_eviction_) { 1935 CACHE_UMA(PERCENTAGE, "ResurrectRatio", 0, stats_.GetResurrectRatio()); 1936 CACHE_UMA(PERCENTAGE, "NoUseRatio", 0, 1937 data_->header.lru.sizes[0] * 100 / data_->header.num_entries); 1938 CACHE_UMA(PERCENTAGE, "LowUseRatio", 0, 1939 data_->header.lru.sizes[1] * 100 / data_->header.num_entries); 1940 CACHE_UMA(PERCENTAGE, "HighUseRatio", 0, 1941 data_->header.lru.sizes[2] * 100 / data_->header.num_entries); 1942 CACHE_UMA(PERCENTAGE, "DeletedRatio", 0, 1943 data_->header.lru.sizes[4] * 100 / data_->header.num_entries); 1944 } 1945 1946 stats_.ResetRatios(); 1947 stats_.SetCounter(Stats::TRIM_ENTRY, 0); 1948 1949 if (cache_type_ == net::DISK_CACHE) 1950 block_files_.ReportStats(); 1951} 1952 1953void BackendImpl::UpgradeTo2_1() { 1954 // 2.1 is basically the same as 2.0, except that new fields are actually 1955 // updated by the new eviction algorithm. 1956 DCHECK(0x20000 == data_->header.version); 1957 data_->header.version = 0x20001; 1958 data_->header.lru.sizes[Rankings::NO_USE] = data_->header.num_entries; 1959} 1960 1961bool BackendImpl::CheckIndex() { 1962 DCHECK(data_); 1963 1964 size_t current_size = index_->GetLength(); 1965 if (current_size < sizeof(Index)) { 1966 LOG(ERROR) << "Corrupt Index file"; 1967 return false; 1968 } 1969 1970 if (new_eviction_) { 1971 // We support versions 2.0 and 2.1, upgrading 2.0 to 2.1. 1972 if (kIndexMagic != data_->header.magic || 1973 kCurrentVersion >> 16 != data_->header.version >> 16) { 1974 LOG(ERROR) << "Invalid file version or magic"; 1975 return false; 1976 } 1977 if (kCurrentVersion == data_->header.version) { 1978 // We need file version 2.1 for the new eviction algorithm. 1979 UpgradeTo2_1(); 1980 } 1981 } else { 1982 if (kIndexMagic != data_->header.magic || 1983 kCurrentVersion != data_->header.version) { 1984 LOG(ERROR) << "Invalid file version or magic"; 1985 return false; 1986 } 1987 } 1988 1989 if (!data_->header.table_len) { 1990 LOG(ERROR) << "Invalid table size"; 1991 return false; 1992 } 1993 1994 if (current_size < GetIndexSize(data_->header.table_len) || 1995 data_->header.table_len & (kBaseTableLen - 1)) { 1996 LOG(ERROR) << "Corrupt Index file"; 1997 return false; 1998 } 1999 2000 AdjustMaxCacheSize(data_->header.table_len); 2001 2002#if !defined(NET_BUILD_STRESS_CACHE) 2003 if (data_->header.num_bytes < 0 || 2004 (max_size_ < kint32max - kDefaultCacheSize && 2005 data_->header.num_bytes > max_size_ + kDefaultCacheSize)) { 2006 LOG(ERROR) << "Invalid cache (current) size"; 2007 return false; 2008 } 2009#endif 2010 2011 if (data_->header.num_entries < 0) { 2012 LOG(ERROR) << "Invalid number of entries"; 2013 return false; 2014 } 2015 2016 if (!mask_) 2017 mask_ = data_->header.table_len - 1; 2018 2019 // Load the table into memory. 2020 return index_->Preload(); 2021} 2022 2023int BackendImpl::CheckAllEntries() { 2024 int num_dirty = 0; 2025 int num_entries = 0; 2026 DCHECK(mask_ < kuint32max); 2027 for (unsigned int i = 0; i <= mask_; i++) { 2028 Addr address(data_->table[i]); 2029 if (!address.is_initialized()) 2030 continue; 2031 for (;;) { 2032 EntryImpl* tmp; 2033 int ret = NewEntry(address, &tmp); 2034 if (ret) { 2035 STRESS_NOTREACHED(); 2036 return ret; 2037 } 2038 scoped_refptr<EntryImpl> cache_entry; 2039 cache_entry.swap(&tmp); 2040 2041 if (cache_entry->dirty()) 2042 num_dirty++; 2043 else if (CheckEntry(cache_entry.get())) 2044 num_entries++; 2045 else 2046 return ERR_INVALID_ENTRY; 2047 2048 DCHECK_EQ(i, cache_entry->entry()->Data()->hash & mask_); 2049 address.set_value(cache_entry->GetNextAddress()); 2050 if (!address.is_initialized()) 2051 break; 2052 } 2053 } 2054 2055 Trace("CheckAllEntries End"); 2056 if (num_entries + num_dirty != data_->header.num_entries) { 2057 LOG(ERROR) << "Number of entries " << num_entries << " " << num_dirty << 2058 " " << data_->header.num_entries; 2059 DCHECK_LT(num_entries, data_->header.num_entries); 2060 return ERR_NUM_ENTRIES_MISMATCH; 2061 } 2062 2063 return num_dirty; 2064} 2065 2066bool BackendImpl::CheckEntry(EntryImpl* cache_entry) { 2067 bool ok = block_files_.IsValid(cache_entry->entry()->address()); 2068 ok = ok && block_files_.IsValid(cache_entry->rankings()->address()); 2069 EntryStore* data = cache_entry->entry()->Data(); 2070 for (size_t i = 0; i < arraysize(data->data_addr); i++) { 2071 if (data->data_addr[i]) { 2072 Addr address(data->data_addr[i]); 2073 if (address.is_block_file()) 2074 ok = ok && block_files_.IsValid(address); 2075 } 2076 } 2077 2078 return ok && cache_entry->rankings()->VerifyHash(); 2079} 2080 2081int BackendImpl::MaxBuffersSize() { 2082 static int64 total_memory = base::SysInfo::AmountOfPhysicalMemory(); 2083 static bool done = false; 2084 2085 if (!done) { 2086 const int kMaxBuffersSize = 30 * 1024 * 1024; 2087 2088 // We want to use up to 2% of the computer's memory. 2089 total_memory = total_memory * 2 / 100; 2090 if (total_memory > kMaxBuffersSize || total_memory <= 0) 2091 total_memory = kMaxBuffersSize; 2092 2093 done = true; 2094 } 2095 2096 return static_cast<int>(total_memory); 2097} 2098 2099} // namespace disk_cache 2100