backend_impl.cc revision 03b57e008b61dfcb1fbad3aea950ae0e001748b0
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.h" 11#include "base/files/file_path.h" 12#include "base/hash.h" 13#include "base/message_loop/message_loop.h" 14#include "base/metrics/field_trial.h" 15#include "base/metrics/histogram.h" 16#include "base/metrics/stats_counters.h" 17#include "base/rand_util.h" 18#include "base/single_thread_task_runner.h" 19#include "base/strings/string_util.h" 20#include "base/strings/stringprintf.h" 21#include "base/sys_info.h" 22#include "base/threading/thread_restrictions.h" 23#include "base/time/time.h" 24#include "base/timer/timer.h" 25#include "net/base/net_errors.h" 26#include "net/disk_cache/blockfile/disk_format.h" 27#include "net/disk_cache/blockfile/entry_impl.h" 28#include "net/disk_cache/blockfile/errors.h" 29#include "net/disk_cache/blockfile/experiments.h" 30#include "net/disk_cache/blockfile/file.h" 31#include "net/disk_cache/blockfile/histogram_macros.h" 32#include "net/disk_cache/blockfile/webfonts_histogram.h" 33#include "net/disk_cache/cache_util.h" 34 35// Provide a BackendImpl object to macros from histogram_macros.h. 36#define CACHE_UMA_BACKEND_IMPL_OBJ this 37 38using base::Time; 39using base::TimeDelta; 40using base::TimeTicks; 41 42namespace { 43 44const char* kIndexName = "index"; 45 46// Seems like ~240 MB correspond to less than 50k entries for 99% of the people. 47// Note that the actual target is to keep the index table load factor under 55% 48// for most users. 49const int k64kEntriesStore = 240 * 1000 * 1000; 50const int kBaseTableLen = 64 * 1024; 51 52// Avoid trimming the cache for the first 5 minutes (10 timer ticks). 53const int kTrimDelay = 10; 54 55int DesiredIndexTableLen(int32 storage_size) { 56 if (storage_size <= k64kEntriesStore) 57 return kBaseTableLen; 58 if (storage_size <= k64kEntriesStore * 2) 59 return kBaseTableLen * 2; 60 if (storage_size <= k64kEntriesStore * 4) 61 return kBaseTableLen * 4; 62 if (storage_size <= k64kEntriesStore * 8) 63 return kBaseTableLen * 8; 64 65 // The biggest storage_size for int32 requires a 4 MB table. 66 return kBaseTableLen * 16; 67} 68 69int MaxStorageSizeForTable(int table_len) { 70 return table_len * (k64kEntriesStore / kBaseTableLen); 71} 72 73size_t GetIndexSize(int table_len) { 74 size_t table_size = sizeof(disk_cache::CacheAddr) * table_len; 75 return sizeof(disk_cache::IndexHeader) + table_size; 76} 77 78// ------------------------------------------------------------------------ 79 80// Sets group for the current experiment. Returns false if the files should be 81// discarded. 82bool InitExperiment(disk_cache::IndexHeader* header, bool cache_created) { 83 if (header->experiment == disk_cache::EXPERIMENT_OLD_FILE1 || 84 header->experiment == disk_cache::EXPERIMENT_OLD_FILE2) { 85 // Discard current cache. 86 return false; 87 } 88 89 if (base::FieldTrialList::FindFullName("SimpleCacheTrial") == 90 "ExperimentControl") { 91 if (cache_created) { 92 header->experiment = disk_cache::EXPERIMENT_SIMPLE_CONTROL; 93 return true; 94 } 95 return header->experiment == disk_cache::EXPERIMENT_SIMPLE_CONTROL; 96 } 97 98 header->experiment = disk_cache::NO_EXPERIMENT; 99 return true; 100} 101 102// A callback to perform final cleanup on the background thread. 103void FinalCleanupCallback(disk_cache::BackendImpl* backend) { 104 backend->CleanupCache(); 105} 106 107} // namespace 108 109// ------------------------------------------------------------------------ 110 111namespace disk_cache { 112 113BackendImpl::BackendImpl( 114 const base::FilePath& path, 115 const scoped_refptr<base::SingleThreadTaskRunner>& cache_thread, 116 net::NetLog* net_log) 117 : background_queue_(this, cache_thread), 118 path_(path), 119 block_files_(path), 120 mask_(0), 121 max_size_(0), 122 up_ticks_(0), 123 cache_type_(net::DISK_CACHE), 124 uma_report_(0), 125 user_flags_(0), 126 init_(false), 127 restarted_(false), 128 unit_test_(false), 129 read_only_(false), 130 disabled_(false), 131 new_eviction_(false), 132 first_timer_(true), 133 user_load_(false), 134 net_log_(net_log), 135 done_(true, false), 136 ptr_factory_(this) { 137} 138 139BackendImpl::BackendImpl( 140 const base::FilePath& path, 141 uint32 mask, 142 const scoped_refptr<base::SingleThreadTaskRunner>& cache_thread, 143 net::NetLog* net_log) 144 : background_queue_(this, cache_thread), 145 path_(path), 146 block_files_(path), 147 mask_(mask), 148 max_size_(0), 149 up_ticks_(0), 150 cache_type_(net::DISK_CACHE), 151 uma_report_(0), 152 user_flags_(kMask), 153 init_(false), 154 restarted_(false), 155 unit_test_(false), 156 read_only_(false), 157 disabled_(false), 158 new_eviction_(false), 159 first_timer_(true), 160 user_load_(false), 161 net_log_(net_log), 162 done_(true, false), 163 ptr_factory_(this) { 164} 165 166BackendImpl::~BackendImpl() { 167 if (user_flags_ & kNoRandom) { 168 // This is a unit test, so we want to be strict about not leaking entries 169 // and completing all the work. 170 background_queue_.WaitForPendingIO(); 171 } else { 172 // This is most likely not a test, so we want to do as little work as 173 // possible at this time, at the price of leaving dirty entries behind. 174 background_queue_.DropPendingIO(); 175 } 176 177 if (background_queue_.BackgroundIsCurrentThread()) { 178 // Unit tests may use the same thread for everything. 179 CleanupCache(); 180 } else { 181 background_queue_.background_thread()->PostTask( 182 FROM_HERE, base::Bind(&FinalCleanupCallback, base::Unretained(this))); 183 // http://crbug.com/74623 184 base::ThreadRestrictions::ScopedAllowWait allow_wait; 185 done_.Wait(); 186 } 187} 188 189int BackendImpl::Init(const CompletionCallback& callback) { 190 background_queue_.Init(callback); 191 return net::ERR_IO_PENDING; 192} 193 194int BackendImpl::SyncInit() { 195#if defined(NET_BUILD_STRESS_CACHE) 196 // Start evictions right away. 197 up_ticks_ = kTrimDelay * 2; 198#endif 199 DCHECK(!init_); 200 if (init_) 201 return net::ERR_FAILED; 202 203 bool create_files = false; 204 if (!InitBackingStore(&create_files)) { 205 ReportError(ERR_STORAGE_ERROR); 206 return net::ERR_FAILED; 207 } 208 209 num_refs_ = num_pending_io_ = max_refs_ = 0; 210 entry_count_ = byte_count_ = 0; 211 212 bool should_create_timer = false; 213 if (!restarted_) { 214 buffer_bytes_ = 0; 215 trace_object_ = TraceObject::GetTraceObject(); 216 should_create_timer = true; 217 } 218 219 init_ = true; 220 Trace("Init"); 221 222 if (data_->header.experiment != NO_EXPERIMENT && 223 cache_type_ != net::DISK_CACHE) { 224 // No experiment for other caches. 225 return net::ERR_FAILED; 226 } 227 228 if (!(user_flags_ & kNoRandom)) { 229 // The unit test controls directly what to test. 230 new_eviction_ = (cache_type_ == net::DISK_CACHE); 231 } 232 233 if (!CheckIndex()) { 234 ReportError(ERR_INIT_FAILED); 235 return net::ERR_FAILED; 236 } 237 238 if (!restarted_ && (create_files || !data_->header.num_entries)) 239 ReportError(ERR_CACHE_CREATED); 240 241 if (!(user_flags_ & kNoRandom) && cache_type_ == net::DISK_CACHE && 242 !InitExperiment(&data_->header, create_files)) { 243 return net::ERR_FAILED; 244 } 245 246 // We don't care if the value overflows. The only thing we care about is that 247 // the id cannot be zero, because that value is used as "not dirty". 248 // Increasing the value once per second gives us many years before we start 249 // having collisions. 250 data_->header.this_id++; 251 if (!data_->header.this_id) 252 data_->header.this_id++; 253 254 bool previous_crash = (data_->header.crash != 0); 255 data_->header.crash = 1; 256 257 if (!block_files_.Init(create_files)) 258 return net::ERR_FAILED; 259 260 // We want to minimize the changes to cache for an AppCache. 261 if (cache_type() == net::APP_CACHE) { 262 DCHECK(!new_eviction_); 263 read_only_ = true; 264 } else if (cache_type() == net::SHADER_CACHE) { 265 DCHECK(!new_eviction_); 266 } 267 268 eviction_.Init(this); 269 270 // stats_ and rankings_ may end up calling back to us so we better be enabled. 271 disabled_ = false; 272 if (!InitStats()) 273 return net::ERR_FAILED; 274 275 disabled_ = !rankings_.Init(this, new_eviction_); 276 277#if defined(STRESS_CACHE_EXTENDED_VALIDATION) 278 trace_object_->EnableTracing(false); 279 int sc = SelfCheck(); 280 if (sc < 0 && sc != ERR_NUM_ENTRIES_MISMATCH) 281 NOTREACHED(); 282 trace_object_->EnableTracing(true); 283#endif 284 285 if (previous_crash) { 286 ReportError(ERR_PREVIOUS_CRASH); 287 } else if (!restarted_) { 288 ReportError(ERR_NO_ERROR); 289 } 290 291 FlushIndex(); 292 293 if (!disabled_ && should_create_timer) { 294 // Create a recurrent timer of 30 secs. 295 int timer_delay = unit_test_ ? 1000 : 30000; 296 timer_.reset(new base::RepeatingTimer<BackendImpl>()); 297 timer_->Start(FROM_HERE, TimeDelta::FromMilliseconds(timer_delay), this, 298 &BackendImpl::OnStatsTimer); 299 } 300 301 return disabled_ ? net::ERR_FAILED : net::OK; 302} 303 304void BackendImpl::CleanupCache() { 305 Trace("Backend Cleanup"); 306 eviction_.Stop(); 307 timer_.reset(); 308 309 if (init_) { 310 StoreStats(); 311 if (data_) 312 data_->header.crash = 0; 313 314 if (user_flags_ & kNoRandom) { 315 // This is a net_unittest, verify that we are not 'leaking' entries. 316 File::WaitForPendingIO(&num_pending_io_); 317 DCHECK(!num_refs_); 318 } else { 319 File::DropPendingIO(); 320 } 321 } 322 block_files_.CloseFiles(); 323 FlushIndex(); 324 index_ = NULL; 325 ptr_factory_.InvalidateWeakPtrs(); 326 done_.Signal(); 327} 328 329// ------------------------------------------------------------------------ 330 331int BackendImpl::OpenPrevEntry(void** iter, Entry** prev_entry, 332 const CompletionCallback& callback) { 333 DCHECK(!callback.is_null()); 334 background_queue_.OpenPrevEntry(iter, prev_entry, callback); 335 return net::ERR_IO_PENDING; 336} 337 338int BackendImpl::SyncOpenEntry(const std::string& key, Entry** entry) { 339 DCHECK(entry); 340 *entry = OpenEntryImpl(key); 341 return (*entry) ? net::OK : net::ERR_FAILED; 342} 343 344int BackendImpl::SyncCreateEntry(const std::string& key, Entry** entry) { 345 DCHECK(entry); 346 *entry = CreateEntryImpl(key); 347 return (*entry) ? net::OK : net::ERR_FAILED; 348} 349 350int BackendImpl::SyncDoomEntry(const std::string& key) { 351 if (disabled_) 352 return net::ERR_FAILED; 353 354 EntryImpl* entry = OpenEntryImpl(key); 355 if (!entry) 356 return net::ERR_FAILED; 357 358 entry->DoomImpl(); 359 entry->Release(); 360 return net::OK; 361} 362 363int BackendImpl::SyncDoomAllEntries() { 364 // This is not really an error, but it is an interesting condition. 365 ReportError(ERR_CACHE_DOOMED); 366 stats_.OnEvent(Stats::DOOM_CACHE); 367 if (!num_refs_) { 368 RestartCache(false); 369 return disabled_ ? net::ERR_FAILED : net::OK; 370 } else { 371 if (disabled_) 372 return net::ERR_FAILED; 373 374 eviction_.TrimCache(true); 375 return net::OK; 376 } 377} 378 379int BackendImpl::SyncDoomEntriesBetween(const base::Time initial_time, 380 const base::Time end_time) { 381 DCHECK_NE(net::APP_CACHE, cache_type_); 382 if (end_time.is_null()) 383 return SyncDoomEntriesSince(initial_time); 384 385 DCHECK(end_time >= initial_time); 386 387 if (disabled_) 388 return net::ERR_FAILED; 389 390 EntryImpl* node; 391 void* iter = NULL; 392 EntryImpl* next = OpenNextEntryImpl(&iter); 393 if (!next) 394 return net::OK; 395 396 while (next) { 397 node = next; 398 next = OpenNextEntryImpl(&iter); 399 400 if (node->GetLastUsed() >= initial_time && 401 node->GetLastUsed() < end_time) { 402 node->DoomImpl(); 403 } else if (node->GetLastUsed() < initial_time) { 404 if (next) 405 next->Release(); 406 next = NULL; 407 SyncEndEnumeration(iter); 408 } 409 410 node->Release(); 411 } 412 413 return net::OK; 414} 415 416// We use OpenNextEntryImpl to retrieve elements from the cache, until we get 417// entries that are too old. 418int BackendImpl::SyncDoomEntriesSince(const base::Time initial_time) { 419 DCHECK_NE(net::APP_CACHE, cache_type_); 420 if (disabled_) 421 return net::ERR_FAILED; 422 423 stats_.OnEvent(Stats::DOOM_RECENT); 424 for (;;) { 425 void* iter = NULL; 426 EntryImpl* entry = OpenNextEntryImpl(&iter); 427 if (!entry) 428 return net::OK; 429 430 if (initial_time > entry->GetLastUsed()) { 431 entry->Release(); 432 SyncEndEnumeration(iter); 433 return net::OK; 434 } 435 436 entry->DoomImpl(); 437 entry->Release(); 438 SyncEndEnumeration(iter); // Dooming the entry invalidates the iterator. 439 } 440} 441 442int BackendImpl::SyncOpenNextEntry(void** iter, Entry** next_entry) { 443 *next_entry = OpenNextEntryImpl(iter); 444 return (*next_entry) ? net::OK : net::ERR_FAILED; 445} 446 447int BackendImpl::SyncOpenPrevEntry(void** iter, Entry** prev_entry) { 448 *prev_entry = OpenPrevEntryImpl(iter); 449 return (*prev_entry) ? net::OK : net::ERR_FAILED; 450} 451 452void BackendImpl::SyncEndEnumeration(void* iter) { 453 scoped_ptr<Rankings::Iterator> iterator( 454 reinterpret_cast<Rankings::Iterator*>(iter)); 455} 456 457void BackendImpl::SyncOnExternalCacheHit(const std::string& key) { 458 if (disabled_) 459 return; 460 461 uint32 hash = base::Hash(key); 462 bool error; 463 EntryImpl* cache_entry = MatchEntry(key, hash, false, Addr(), &error); 464 if (cache_entry) { 465 if (ENTRY_NORMAL == cache_entry->entry()->Data()->state) { 466 UpdateRank(cache_entry, cache_type() == net::SHADER_CACHE); 467 } 468 cache_entry->Release(); 469 } 470} 471 472EntryImpl* BackendImpl::OpenEntryImpl(const std::string& key) { 473 if (disabled_) 474 return NULL; 475 476 TimeTicks start = TimeTicks::Now(); 477 uint32 hash = base::Hash(key); 478 Trace("Open hash 0x%x", hash); 479 480 bool error; 481 EntryImpl* cache_entry = MatchEntry(key, hash, false, Addr(), &error); 482 if (cache_entry && ENTRY_NORMAL != cache_entry->entry()->Data()->state) { 483 // The entry was already evicted. 484 cache_entry->Release(); 485 cache_entry = NULL; 486 web_fonts_histogram::RecordEvictedEntry(key); 487 } else if (!cache_entry) { 488 web_fonts_histogram::RecordCacheMiss(key); 489 } 490 491 int current_size = data_->header.num_bytes / (1024 * 1024); 492 int64 total_hours = stats_.GetCounter(Stats::TIMER) / 120; 493 int64 no_use_hours = stats_.GetCounter(Stats::LAST_REPORT_TIMER) / 120; 494 int64 use_hours = total_hours - no_use_hours; 495 496 if (!cache_entry) { 497 CACHE_UMA(AGE_MS, "OpenTime.Miss", 0, start); 498 CACHE_UMA(COUNTS_10000, "AllOpenBySize.Miss", 0, current_size); 499 CACHE_UMA(HOURS, "AllOpenByTotalHours.Miss", 0, total_hours); 500 CACHE_UMA(HOURS, "AllOpenByUseHours.Miss", 0, use_hours); 501 stats_.OnEvent(Stats::OPEN_MISS); 502 return NULL; 503 } 504 505 eviction_.OnOpenEntry(cache_entry); 506 entry_count_++; 507 508 Trace("Open hash 0x%x end: 0x%x", hash, 509 cache_entry->entry()->address().value()); 510 CACHE_UMA(AGE_MS, "OpenTime", 0, start); 511 CACHE_UMA(COUNTS_10000, "AllOpenBySize.Hit", 0, current_size); 512 CACHE_UMA(HOURS, "AllOpenByTotalHours.Hit", 0, total_hours); 513 CACHE_UMA(HOURS, "AllOpenByUseHours.Hit", 0, use_hours); 514 stats_.OnEvent(Stats::OPEN_HIT); 515 web_fonts_histogram::RecordCacheHit(cache_entry); 516 SIMPLE_STATS_COUNTER("disk_cache.hit"); 517 return cache_entry; 518} 519 520EntryImpl* BackendImpl::CreateEntryImpl(const std::string& key) { 521 if (disabled_ || key.empty()) 522 return NULL; 523 524 TimeTicks start = TimeTicks::Now(); 525 uint32 hash = base::Hash(key); 526 Trace("Create hash 0x%x", hash); 527 528 scoped_refptr<EntryImpl> parent; 529 Addr entry_address(data_->table[hash & mask_]); 530 if (entry_address.is_initialized()) { 531 // We have an entry already. It could be the one we are looking for, or just 532 // a hash conflict. 533 bool error; 534 EntryImpl* old_entry = MatchEntry(key, hash, false, Addr(), &error); 535 if (old_entry) 536 return ResurrectEntry(old_entry); 537 538 EntryImpl* parent_entry = MatchEntry(key, hash, true, Addr(), &error); 539 DCHECK(!error); 540 if (parent_entry) { 541 parent.swap(&parent_entry); 542 } else if (data_->table[hash & mask_]) { 543 // We should have corrected the problem. 544 NOTREACHED(); 545 return NULL; 546 } 547 } 548 549 // The general flow is to allocate disk space and initialize the entry data, 550 // followed by saving that to disk, then linking the entry though the index 551 // and finally through the lists. If there is a crash in this process, we may 552 // end up with: 553 // a. Used, unreferenced empty blocks on disk (basically just garbage). 554 // b. Used, unreferenced but meaningful data on disk (more garbage). 555 // c. A fully formed entry, reachable only through the index. 556 // d. A fully formed entry, also reachable through the lists, but still dirty. 557 // 558 // Anything after (b) can be automatically cleaned up. We may consider saving 559 // the current operation (as we do while manipulating the lists) so that we 560 // can detect and cleanup (a) and (b). 561 562 int num_blocks = EntryImpl::NumBlocksForEntry(key.size()); 563 if (!block_files_.CreateBlock(BLOCK_256, num_blocks, &entry_address)) { 564 LOG(ERROR) << "Create entry failed " << key.c_str(); 565 stats_.OnEvent(Stats::CREATE_ERROR); 566 return NULL; 567 } 568 569 Addr node_address(0); 570 if (!block_files_.CreateBlock(RANKINGS, 1, &node_address)) { 571 block_files_.DeleteBlock(entry_address, false); 572 LOG(ERROR) << "Create entry failed " << key.c_str(); 573 stats_.OnEvent(Stats::CREATE_ERROR); 574 return NULL; 575 } 576 577 scoped_refptr<EntryImpl> cache_entry( 578 new EntryImpl(this, entry_address, false)); 579 IncreaseNumRefs(); 580 581 if (!cache_entry->CreateEntry(node_address, key, hash)) { 582 block_files_.DeleteBlock(entry_address, false); 583 block_files_.DeleteBlock(node_address, false); 584 LOG(ERROR) << "Create entry failed " << key.c_str(); 585 stats_.OnEvent(Stats::CREATE_ERROR); 586 return NULL; 587 } 588 589 cache_entry->BeginLogging(net_log_, true); 590 591 // We are not failing the operation; let's add this to the map. 592 open_entries_[entry_address.value()] = cache_entry.get(); 593 594 // Save the entry. 595 cache_entry->entry()->Store(); 596 cache_entry->rankings()->Store(); 597 IncreaseNumEntries(); 598 entry_count_++; 599 600 // Link this entry through the index. 601 if (parent.get()) { 602 parent->SetNextAddress(entry_address); 603 } else { 604 data_->table[hash & mask_] = entry_address.value(); 605 } 606 607 // Link this entry through the lists. 608 eviction_.OnCreateEntry(cache_entry.get()); 609 610 CACHE_UMA(AGE_MS, "CreateTime", 0, start); 611 stats_.OnEvent(Stats::CREATE_HIT); 612 SIMPLE_STATS_COUNTER("disk_cache.miss"); 613 Trace("create entry hit "); 614 FlushIndex(); 615 cache_entry->AddRef(); 616 return cache_entry.get(); 617} 618 619EntryImpl* BackendImpl::OpenNextEntryImpl(void** iter) { 620 return OpenFollowingEntry(true, iter); 621} 622 623EntryImpl* BackendImpl::OpenPrevEntryImpl(void** iter) { 624 return OpenFollowingEntry(false, iter); 625} 626 627bool BackendImpl::SetMaxSize(int max_bytes) { 628 COMPILE_ASSERT(sizeof(max_bytes) == sizeof(max_size_), unsupported_int_model); 629 if (max_bytes < 0) 630 return false; 631 632 // Zero size means use the default. 633 if (!max_bytes) 634 return true; 635 636 // Avoid a DCHECK later on. 637 if (max_bytes >= kint32max - kint32max / 10) 638 max_bytes = kint32max - kint32max / 10 - 1; 639 640 user_flags_ |= kMaxSize; 641 max_size_ = max_bytes; 642 return true; 643} 644 645void BackendImpl::SetType(net::CacheType type) { 646 DCHECK_NE(net::MEMORY_CACHE, type); 647 cache_type_ = type; 648} 649 650base::FilePath BackendImpl::GetFileName(Addr address) const { 651 if (!address.is_separate_file() || !address.is_initialized()) { 652 NOTREACHED(); 653 return base::FilePath(); 654 } 655 656 std::string tmp = base::StringPrintf("f_%06x", address.FileNumber()); 657 return path_.AppendASCII(tmp); 658} 659 660MappedFile* BackendImpl::File(Addr address) { 661 if (disabled_) 662 return NULL; 663 return block_files_.GetFile(address); 664} 665 666base::WeakPtr<InFlightBackendIO> BackendImpl::GetBackgroundQueue() { 667 return background_queue_.GetWeakPtr(); 668} 669 670bool BackendImpl::CreateExternalFile(Addr* address) { 671 int file_number = data_->header.last_file + 1; 672 Addr file_address(0); 673 bool success = false; 674 for (int i = 0; i < 0x0fffffff; i++, file_number++) { 675 if (!file_address.SetFileNumber(file_number)) { 676 file_number = 1; 677 continue; 678 } 679 base::FilePath name = GetFileName(file_address); 680 int flags = base::File::FLAG_READ | base::File::FLAG_WRITE | 681 base::File::FLAG_CREATE | base::File::FLAG_EXCLUSIVE_WRITE; 682 base::File file(name, flags); 683 if (!file.IsValid()) { 684 base::File::Error error = file.error_details(); 685 if (error != base::File::FILE_ERROR_EXISTS) { 686 LOG(ERROR) << "Unable to create file: " << error; 687 return false; 688 } 689 continue; 690 } 691 692 success = true; 693 break; 694 } 695 696 DCHECK(success); 697 if (!success) 698 return false; 699 700 data_->header.last_file = file_number; 701 address->set_value(file_address.value()); 702 return true; 703} 704 705bool BackendImpl::CreateBlock(FileType block_type, int block_count, 706 Addr* block_address) { 707 return block_files_.CreateBlock(block_type, block_count, block_address); 708} 709 710void BackendImpl::DeleteBlock(Addr block_address, bool deep) { 711 block_files_.DeleteBlock(block_address, deep); 712} 713 714LruData* BackendImpl::GetLruData() { 715 return &data_->header.lru; 716} 717 718void BackendImpl::UpdateRank(EntryImpl* entry, bool modified) { 719 if (read_only_ || (!modified && cache_type() == net::SHADER_CACHE)) 720 return; 721 eviction_.UpdateRank(entry, modified); 722} 723 724void BackendImpl::RecoveredEntry(CacheRankingsBlock* rankings) { 725 Addr address(rankings->Data()->contents); 726 EntryImpl* cache_entry = NULL; 727 if (NewEntry(address, &cache_entry)) { 728 STRESS_NOTREACHED(); 729 return; 730 } 731 732 uint32 hash = cache_entry->GetHash(); 733 cache_entry->Release(); 734 735 // Anything on the table means that this entry is there. 736 if (data_->table[hash & mask_]) 737 return; 738 739 data_->table[hash & mask_] = address.value(); 740 FlushIndex(); 741} 742 743void BackendImpl::InternalDoomEntry(EntryImpl* entry) { 744 uint32 hash = entry->GetHash(); 745 std::string key = entry->GetKey(); 746 Addr entry_addr = entry->entry()->address(); 747 bool error; 748 EntryImpl* parent_entry = MatchEntry(key, hash, true, entry_addr, &error); 749 CacheAddr child(entry->GetNextAddress()); 750 751 Trace("Doom entry 0x%p", entry); 752 753 if (!entry->doomed()) { 754 // We may have doomed this entry from within MatchEntry. 755 eviction_.OnDoomEntry(entry); 756 entry->InternalDoom(); 757 if (!new_eviction_) { 758 DecreaseNumEntries(); 759 } 760 stats_.OnEvent(Stats::DOOM_ENTRY); 761 } 762 763 if (parent_entry) { 764 parent_entry->SetNextAddress(Addr(child)); 765 parent_entry->Release(); 766 } else if (!error) { 767 data_->table[hash & mask_] = child; 768 } 769 770 FlushIndex(); 771} 772 773#if defined(NET_BUILD_STRESS_CACHE) 774 775CacheAddr BackendImpl::GetNextAddr(Addr address) { 776 EntriesMap::iterator it = open_entries_.find(address.value()); 777 if (it != open_entries_.end()) { 778 EntryImpl* this_entry = it->second; 779 return this_entry->GetNextAddress(); 780 } 781 DCHECK(block_files_.IsValid(address)); 782 DCHECK(!address.is_separate_file() && address.file_type() == BLOCK_256); 783 784 CacheEntryBlock entry(File(address), address); 785 CHECK(entry.Load()); 786 return entry.Data()->next; 787} 788 789void BackendImpl::NotLinked(EntryImpl* entry) { 790 Addr entry_addr = entry->entry()->address(); 791 uint32 i = entry->GetHash() & mask_; 792 Addr address(data_->table[i]); 793 if (!address.is_initialized()) 794 return; 795 796 for (;;) { 797 DCHECK(entry_addr.value() != address.value()); 798 address.set_value(GetNextAddr(address)); 799 if (!address.is_initialized()) 800 break; 801 } 802} 803#endif // NET_BUILD_STRESS_CACHE 804 805// An entry may be linked on the DELETED list for a while after being doomed. 806// This function is called when we want to remove it. 807void BackendImpl::RemoveEntry(EntryImpl* entry) { 808#if defined(NET_BUILD_STRESS_CACHE) 809 NotLinked(entry); 810#endif 811 if (!new_eviction_) 812 return; 813 814 DCHECK_NE(ENTRY_NORMAL, entry->entry()->Data()->state); 815 816 Trace("Remove entry 0x%p", entry); 817 eviction_.OnDestroyEntry(entry); 818 DecreaseNumEntries(); 819} 820 821void BackendImpl::OnEntryDestroyBegin(Addr address) { 822 EntriesMap::iterator it = open_entries_.find(address.value()); 823 if (it != open_entries_.end()) 824 open_entries_.erase(it); 825} 826 827void BackendImpl::OnEntryDestroyEnd() { 828 DecreaseNumRefs(); 829 if (data_->header.num_bytes > max_size_ && !read_only_ && 830 (up_ticks_ > kTrimDelay || user_flags_ & kNoRandom)) 831 eviction_.TrimCache(false); 832} 833 834EntryImpl* BackendImpl::GetOpenEntry(CacheRankingsBlock* rankings) const { 835 DCHECK(rankings->HasData()); 836 EntriesMap::const_iterator it = 837 open_entries_.find(rankings->Data()->contents); 838 if (it != open_entries_.end()) { 839 // We have this entry in memory. 840 return it->second; 841 } 842 843 return NULL; 844} 845 846int32 BackendImpl::GetCurrentEntryId() const { 847 return data_->header.this_id; 848} 849 850int BackendImpl::MaxFileSize() const { 851 return cache_type() == net::PNACL_CACHE ? max_size_ : max_size_ / 8; 852} 853 854void BackendImpl::ModifyStorageSize(int32 old_size, int32 new_size) { 855 if (disabled_ || old_size == new_size) 856 return; 857 if (old_size > new_size) 858 SubstractStorageSize(old_size - new_size); 859 else 860 AddStorageSize(new_size - old_size); 861 862 FlushIndex(); 863 864 // Update the usage statistics. 865 stats_.ModifyStorageStats(old_size, new_size); 866} 867 868void BackendImpl::TooMuchStorageRequested(int32 size) { 869 stats_.ModifyStorageStats(0, size); 870} 871 872bool BackendImpl::IsAllocAllowed(int current_size, int new_size) { 873 DCHECK_GT(new_size, current_size); 874 if (user_flags_ & kNoBuffering) 875 return false; 876 877 int to_add = new_size - current_size; 878 if (buffer_bytes_ + to_add > MaxBuffersSize()) 879 return false; 880 881 buffer_bytes_ += to_add; 882 CACHE_UMA(COUNTS_50000, "BufferBytes", 0, buffer_bytes_ / 1024); 883 return true; 884} 885 886void BackendImpl::BufferDeleted(int size) { 887 buffer_bytes_ -= size; 888 DCHECK_GE(size, 0); 889} 890 891bool BackendImpl::IsLoaded() const { 892 CACHE_UMA(COUNTS, "PendingIO", 0, num_pending_io_); 893 if (user_flags_ & kNoLoadProtection) 894 return false; 895 896 return (num_pending_io_ > 5 || user_load_); 897} 898 899std::string BackendImpl::HistogramName(const char* name, int experiment) const { 900 if (!experiment) 901 return base::StringPrintf("DiskCache.%d.%s", cache_type_, name); 902 return base::StringPrintf("DiskCache.%d.%s_%d", cache_type_, 903 name, experiment); 904} 905 906base::WeakPtr<BackendImpl> BackendImpl::GetWeakPtr() { 907 return ptr_factory_.GetWeakPtr(); 908} 909 910// We want to remove biases from some histograms so we only send data once per 911// week. 912bool BackendImpl::ShouldReportAgain() { 913 if (uma_report_) 914 return uma_report_ == 2; 915 916 uma_report_++; 917 int64 last_report = stats_.GetCounter(Stats::LAST_REPORT); 918 Time last_time = Time::FromInternalValue(last_report); 919 if (!last_report || (Time::Now() - last_time).InDays() >= 7) { 920 stats_.SetCounter(Stats::LAST_REPORT, Time::Now().ToInternalValue()); 921 uma_report_++; 922 return true; 923 } 924 return false; 925} 926 927void BackendImpl::FirstEviction() { 928 DCHECK(data_->header.create_time); 929 if (!GetEntryCount()) 930 return; // This is just for unit tests. 931 932 Time create_time = Time::FromInternalValue(data_->header.create_time); 933 CACHE_UMA(AGE, "FillupAge", 0, create_time); 934 935 int64 use_time = stats_.GetCounter(Stats::TIMER); 936 CACHE_UMA(HOURS, "FillupTime", 0, static_cast<int>(use_time / 120)); 937 CACHE_UMA(PERCENTAGE, "FirstHitRatio", 0, stats_.GetHitRatio()); 938 939 if (!use_time) 940 use_time = 1; 941 CACHE_UMA(COUNTS_10000, "FirstEntryAccessRate", 0, 942 static_cast<int>(data_->header.num_entries / use_time)); 943 CACHE_UMA(COUNTS, "FirstByteIORate", 0, 944 static_cast<int>((data_->header.num_bytes / 1024) / use_time)); 945 946 int avg_size = data_->header.num_bytes / GetEntryCount(); 947 CACHE_UMA(COUNTS, "FirstEntrySize", 0, avg_size); 948 949 int large_entries_bytes = stats_.GetLargeEntriesSize(); 950 int large_ratio = large_entries_bytes * 100 / data_->header.num_bytes; 951 CACHE_UMA(PERCENTAGE, "FirstLargeEntriesRatio", 0, large_ratio); 952 953 if (new_eviction_) { 954 CACHE_UMA(PERCENTAGE, "FirstResurrectRatio", 0, stats_.GetResurrectRatio()); 955 CACHE_UMA(PERCENTAGE, "FirstNoUseRatio", 0, 956 data_->header.lru.sizes[0] * 100 / data_->header.num_entries); 957 CACHE_UMA(PERCENTAGE, "FirstLowUseRatio", 0, 958 data_->header.lru.sizes[1] * 100 / data_->header.num_entries); 959 CACHE_UMA(PERCENTAGE, "FirstHighUseRatio", 0, 960 data_->header.lru.sizes[2] * 100 / data_->header.num_entries); 961 } 962 963 stats_.ResetRatios(); 964} 965 966void BackendImpl::CriticalError(int error) { 967 STRESS_NOTREACHED(); 968 LOG(ERROR) << "Critical error found " << error; 969 if (disabled_) 970 return; 971 972 stats_.OnEvent(Stats::FATAL_ERROR); 973 LogStats(); 974 ReportError(error); 975 976 // Setting the index table length to an invalid value will force re-creation 977 // of the cache files. 978 data_->header.table_len = 1; 979 disabled_ = true; 980 981 if (!num_refs_) 982 base::MessageLoop::current()->PostTask( 983 FROM_HERE, base::Bind(&BackendImpl::RestartCache, GetWeakPtr(), true)); 984} 985 986void BackendImpl::ReportError(int error) { 987 STRESS_DCHECK(!error || error == ERR_PREVIOUS_CRASH || 988 error == ERR_CACHE_CREATED); 989 990 // We transmit positive numbers, instead of direct error codes. 991 DCHECK_LE(error, 0); 992 CACHE_UMA(CACHE_ERROR, "Error", 0, error * -1); 993} 994 995void BackendImpl::OnEvent(Stats::Counters an_event) { 996 stats_.OnEvent(an_event); 997} 998 999void BackendImpl::OnRead(int32 bytes) { 1000 DCHECK_GE(bytes, 0); 1001 byte_count_ += bytes; 1002 if (byte_count_ < 0) 1003 byte_count_ = kint32max; 1004} 1005 1006void BackendImpl::OnWrite(int32 bytes) { 1007 // We use the same implementation as OnRead... just log the number of bytes. 1008 OnRead(bytes); 1009} 1010 1011void BackendImpl::OnStatsTimer() { 1012 if (disabled_) 1013 return; 1014 1015 stats_.OnEvent(Stats::TIMER); 1016 int64 time = stats_.GetCounter(Stats::TIMER); 1017 int64 current = stats_.GetCounter(Stats::OPEN_ENTRIES); 1018 1019 // OPEN_ENTRIES is a sampled average of the number of open entries, avoiding 1020 // the bias towards 0. 1021 if (num_refs_ && (current != num_refs_)) { 1022 int64 diff = (num_refs_ - current) / 50; 1023 if (!diff) 1024 diff = num_refs_ > current ? 1 : -1; 1025 current = current + diff; 1026 stats_.SetCounter(Stats::OPEN_ENTRIES, current); 1027 stats_.SetCounter(Stats::MAX_ENTRIES, max_refs_); 1028 } 1029 1030 CACHE_UMA(COUNTS, "NumberOfReferences", 0, num_refs_); 1031 1032 CACHE_UMA(COUNTS_10000, "EntryAccessRate", 0, entry_count_); 1033 CACHE_UMA(COUNTS, "ByteIORate", 0, byte_count_ / 1024); 1034 1035 // These values cover about 99.5% of the population (Oct 2011). 1036 user_load_ = (entry_count_ > 300 || byte_count_ > 7 * 1024 * 1024); 1037 entry_count_ = 0; 1038 byte_count_ = 0; 1039 up_ticks_++; 1040 1041 if (!data_) 1042 first_timer_ = false; 1043 if (first_timer_) { 1044 first_timer_ = false; 1045 if (ShouldReportAgain()) 1046 ReportStats(); 1047 } 1048 1049 // Save stats to disk at 5 min intervals. 1050 if (time % 10 == 0) 1051 StoreStats(); 1052} 1053 1054void BackendImpl::IncrementIoCount() { 1055 num_pending_io_++; 1056} 1057 1058void BackendImpl::DecrementIoCount() { 1059 num_pending_io_--; 1060} 1061 1062void BackendImpl::SetUnitTestMode() { 1063 user_flags_ |= kUnitTestMode; 1064 unit_test_ = true; 1065} 1066 1067void BackendImpl::SetUpgradeMode() { 1068 user_flags_ |= kUpgradeMode; 1069 read_only_ = true; 1070} 1071 1072void BackendImpl::SetNewEviction() { 1073 user_flags_ |= kNewEviction; 1074 new_eviction_ = true; 1075} 1076 1077void BackendImpl::SetFlags(uint32 flags) { 1078 user_flags_ |= flags; 1079} 1080 1081void BackendImpl::ClearRefCountForTest() { 1082 num_refs_ = 0; 1083} 1084 1085int BackendImpl::FlushQueueForTest(const CompletionCallback& callback) { 1086 background_queue_.FlushQueue(callback); 1087 return net::ERR_IO_PENDING; 1088} 1089 1090int BackendImpl::RunTaskForTest(const base::Closure& task, 1091 const CompletionCallback& callback) { 1092 background_queue_.RunTask(task, callback); 1093 return net::ERR_IO_PENDING; 1094} 1095 1096void BackendImpl::TrimForTest(bool empty) { 1097 eviction_.SetTestMode(); 1098 eviction_.TrimCache(empty); 1099} 1100 1101void BackendImpl::TrimDeletedListForTest(bool empty) { 1102 eviction_.SetTestMode(); 1103 eviction_.TrimDeletedList(empty); 1104} 1105 1106base::RepeatingTimer<BackendImpl>* BackendImpl::GetTimerForTest() { 1107 return timer_.get(); 1108} 1109 1110int BackendImpl::SelfCheck() { 1111 if (!init_) { 1112 LOG(ERROR) << "Init failed"; 1113 return ERR_INIT_FAILED; 1114 } 1115 1116 int num_entries = rankings_.SelfCheck(); 1117 if (num_entries < 0) { 1118 LOG(ERROR) << "Invalid rankings list, error " << num_entries; 1119#if !defined(NET_BUILD_STRESS_CACHE) 1120 return num_entries; 1121#endif 1122 } 1123 1124 if (num_entries != data_->header.num_entries) { 1125 LOG(ERROR) << "Number of entries mismatch"; 1126#if !defined(NET_BUILD_STRESS_CACHE) 1127 return ERR_NUM_ENTRIES_MISMATCH; 1128#endif 1129 } 1130 1131 return CheckAllEntries(); 1132} 1133 1134void BackendImpl::FlushIndex() { 1135 if (index_.get() && !disabled_) 1136 index_->Flush(); 1137} 1138 1139// ------------------------------------------------------------------------ 1140 1141net::CacheType BackendImpl::GetCacheType() const { 1142 return cache_type_; 1143} 1144 1145int32 BackendImpl::GetEntryCount() const { 1146 if (!index_.get() || disabled_) 1147 return 0; 1148 // num_entries includes entries already evicted. 1149 int32 not_deleted = data_->header.num_entries - 1150 data_->header.lru.sizes[Rankings::DELETED]; 1151 1152 if (not_deleted < 0) { 1153 NOTREACHED(); 1154 not_deleted = 0; 1155 } 1156 1157 return not_deleted; 1158} 1159 1160int BackendImpl::OpenEntry(const std::string& key, Entry** entry, 1161 const CompletionCallback& callback) { 1162 DCHECK(!callback.is_null()); 1163 background_queue_.OpenEntry(key, entry, callback); 1164 return net::ERR_IO_PENDING; 1165} 1166 1167int BackendImpl::CreateEntry(const std::string& key, Entry** entry, 1168 const CompletionCallback& callback) { 1169 DCHECK(!callback.is_null()); 1170 background_queue_.CreateEntry(key, entry, callback); 1171 return net::ERR_IO_PENDING; 1172} 1173 1174int BackendImpl::DoomEntry(const std::string& key, 1175 const CompletionCallback& callback) { 1176 DCHECK(!callback.is_null()); 1177 background_queue_.DoomEntry(key, callback); 1178 return net::ERR_IO_PENDING; 1179} 1180 1181int BackendImpl::DoomAllEntries(const CompletionCallback& callback) { 1182 DCHECK(!callback.is_null()); 1183 background_queue_.DoomAllEntries(callback); 1184 return net::ERR_IO_PENDING; 1185} 1186 1187int BackendImpl::DoomEntriesBetween(const base::Time initial_time, 1188 const base::Time end_time, 1189 const CompletionCallback& callback) { 1190 DCHECK(!callback.is_null()); 1191 background_queue_.DoomEntriesBetween(initial_time, end_time, callback); 1192 return net::ERR_IO_PENDING; 1193} 1194 1195int BackendImpl::DoomEntriesSince(const base::Time initial_time, 1196 const CompletionCallback& callback) { 1197 DCHECK(!callback.is_null()); 1198 background_queue_.DoomEntriesSince(initial_time, callback); 1199 return net::ERR_IO_PENDING; 1200} 1201 1202int BackendImpl::OpenNextEntry(void** iter, Entry** next_entry, 1203 const CompletionCallback& callback) { 1204 DCHECK(!callback.is_null()); 1205 background_queue_.OpenNextEntry(iter, next_entry, callback); 1206 return net::ERR_IO_PENDING; 1207} 1208 1209void BackendImpl::EndEnumeration(void** iter) { 1210 background_queue_.EndEnumeration(*iter); 1211 *iter = NULL; 1212} 1213 1214void BackendImpl::GetStats(StatsItems* stats) { 1215 if (disabled_) 1216 return; 1217 1218 std::pair<std::string, std::string> item; 1219 1220 item.first = "Entries"; 1221 item.second = base::StringPrintf("%d", data_->header.num_entries); 1222 stats->push_back(item); 1223 1224 item.first = "Pending IO"; 1225 item.second = base::StringPrintf("%d", num_pending_io_); 1226 stats->push_back(item); 1227 1228 item.first = "Max size"; 1229 item.second = base::StringPrintf("%d", max_size_); 1230 stats->push_back(item); 1231 1232 item.first = "Current size"; 1233 item.second = base::StringPrintf("%d", data_->header.num_bytes); 1234 stats->push_back(item); 1235 1236 item.first = "Cache type"; 1237 item.second = "Blockfile Cache"; 1238 stats->push_back(item); 1239 1240 stats_.GetItems(stats); 1241} 1242 1243void BackendImpl::OnExternalCacheHit(const std::string& key) { 1244 background_queue_.OnExternalCacheHit(key); 1245} 1246 1247// ------------------------------------------------------------------------ 1248 1249// We just created a new file so we're going to write the header and set the 1250// file length to include the hash table (zero filled). 1251bool BackendImpl::CreateBackingStore(disk_cache::File* file) { 1252 AdjustMaxCacheSize(0); 1253 1254 IndexHeader header; 1255 header.table_len = DesiredIndexTableLen(max_size_); 1256 1257 // We need file version 2.1 for the new eviction algorithm. 1258 if (new_eviction_) 1259 header.version = 0x20001; 1260 1261 header.create_time = Time::Now().ToInternalValue(); 1262 1263 if (!file->Write(&header, sizeof(header), 0)) 1264 return false; 1265 1266 return file->SetLength(GetIndexSize(header.table_len)); 1267} 1268 1269bool BackendImpl::InitBackingStore(bool* file_created) { 1270 if (!base::CreateDirectory(path_)) 1271 return false; 1272 1273 base::FilePath index_name = path_.AppendASCII(kIndexName); 1274 1275 int flags = base::File::FLAG_READ | base::File::FLAG_WRITE | 1276 base::File::FLAG_OPEN_ALWAYS | base::File::FLAG_EXCLUSIVE_WRITE; 1277 base::File base_file(index_name, flags); 1278 if (!base_file.IsValid()) 1279 return false; 1280 1281 bool ret = true; 1282 *file_created = base_file.created(); 1283 1284 scoped_refptr<disk_cache::File> file(new disk_cache::File(base_file.Pass())); 1285 if (*file_created) 1286 ret = CreateBackingStore(file.get()); 1287 1288 file = NULL; 1289 if (!ret) 1290 return false; 1291 1292 index_ = new MappedFile(); 1293 data_ = static_cast<Index*>(index_->Init(index_name, 0)); 1294 if (!data_) { 1295 LOG(ERROR) << "Unable to map Index file"; 1296 return false; 1297 } 1298 1299 if (index_->GetLength() < sizeof(Index)) { 1300 // We verify this again on CheckIndex() but it's easier to make sure now 1301 // that the header is there. 1302 LOG(ERROR) << "Corrupt Index file"; 1303 return false; 1304 } 1305 1306 return true; 1307} 1308 1309// The maximum cache size will be either set explicitly by the caller, or 1310// calculated by this code. 1311void BackendImpl::AdjustMaxCacheSize(int table_len) { 1312 if (max_size_) 1313 return; 1314 1315 // If table_len is provided, the index file exists. 1316 DCHECK(!table_len || data_->header.magic); 1317 1318 // The user is not setting the size, let's figure it out. 1319 int64 available = base::SysInfo::AmountOfFreeDiskSpace(path_); 1320 if (available < 0) { 1321 max_size_ = kDefaultCacheSize; 1322 return; 1323 } 1324 1325 if (table_len) 1326 available += data_->header.num_bytes; 1327 1328 max_size_ = PreferredCacheSize(available); 1329 1330 if (!table_len) 1331 return; 1332 1333 // If we already have a table, adjust the size to it. 1334 int current_max_size = MaxStorageSizeForTable(table_len); 1335 if (max_size_ > current_max_size) 1336 max_size_= current_max_size; 1337} 1338 1339bool BackendImpl::InitStats() { 1340 Addr address(data_->header.stats); 1341 int size = stats_.StorageSize(); 1342 1343 if (!address.is_initialized()) { 1344 FileType file_type = Addr::RequiredFileType(size); 1345 DCHECK_NE(file_type, EXTERNAL); 1346 int num_blocks = Addr::RequiredBlocks(size, file_type); 1347 1348 if (!CreateBlock(file_type, num_blocks, &address)) 1349 return false; 1350 1351 data_->header.stats = address.value(); 1352 return stats_.Init(NULL, 0, address); 1353 } 1354 1355 if (!address.is_block_file()) { 1356 NOTREACHED(); 1357 return false; 1358 } 1359 1360 // Load the required data. 1361 size = address.num_blocks() * address.BlockSize(); 1362 MappedFile* file = File(address); 1363 if (!file) 1364 return false; 1365 1366 scoped_ptr<char[]> data(new char[size]); 1367 size_t offset = address.start_block() * address.BlockSize() + 1368 kBlockHeaderSize; 1369 if (!file->Read(data.get(), size, offset)) 1370 return false; 1371 1372 if (!stats_.Init(data.get(), size, address)) 1373 return false; 1374 if (cache_type_ == net::DISK_CACHE && ShouldReportAgain()) 1375 stats_.InitSizeHistogram(); 1376 return true; 1377} 1378 1379void BackendImpl::StoreStats() { 1380 int size = stats_.StorageSize(); 1381 scoped_ptr<char[]> data(new char[size]); 1382 Addr address; 1383 size = stats_.SerializeStats(data.get(), size, &address); 1384 DCHECK(size); 1385 if (!address.is_initialized()) 1386 return; 1387 1388 MappedFile* file = File(address); 1389 if (!file) 1390 return; 1391 1392 size_t offset = address.start_block() * address.BlockSize() + 1393 kBlockHeaderSize; 1394 file->Write(data.get(), size, offset); // ignore result. 1395} 1396 1397void BackendImpl::RestartCache(bool failure) { 1398 int64 errors = stats_.GetCounter(Stats::FATAL_ERROR); 1399 int64 full_dooms = stats_.GetCounter(Stats::DOOM_CACHE); 1400 int64 partial_dooms = stats_.GetCounter(Stats::DOOM_RECENT); 1401 int64 last_report = stats_.GetCounter(Stats::LAST_REPORT); 1402 1403 PrepareForRestart(); 1404 if (failure) { 1405 DCHECK(!num_refs_); 1406 DCHECK(!open_entries_.size()); 1407 DelayedCacheCleanup(path_); 1408 } else { 1409 DeleteCache(path_, false); 1410 } 1411 1412 // Don't call Init() if directed by the unit test: we are simulating a failure 1413 // trying to re-enable the cache. 1414 if (unit_test_) 1415 init_ = true; // Let the destructor do proper cleanup. 1416 else if (SyncInit() == net::OK) { 1417 stats_.SetCounter(Stats::FATAL_ERROR, errors); 1418 stats_.SetCounter(Stats::DOOM_CACHE, full_dooms); 1419 stats_.SetCounter(Stats::DOOM_RECENT, partial_dooms); 1420 stats_.SetCounter(Stats::LAST_REPORT, last_report); 1421 } 1422} 1423 1424void BackendImpl::PrepareForRestart() { 1425 // Reset the mask_ if it was not given by the user. 1426 if (!(user_flags_ & kMask)) 1427 mask_ = 0; 1428 1429 if (!(user_flags_ & kNewEviction)) 1430 new_eviction_ = false; 1431 1432 disabled_ = true; 1433 data_->header.crash = 0; 1434 index_->Flush(); 1435 index_ = NULL; 1436 data_ = NULL; 1437 block_files_.CloseFiles(); 1438 rankings_.Reset(); 1439 init_ = false; 1440 restarted_ = true; 1441} 1442 1443int BackendImpl::NewEntry(Addr address, EntryImpl** entry) { 1444 EntriesMap::iterator it = open_entries_.find(address.value()); 1445 if (it != open_entries_.end()) { 1446 // Easy job. This entry is already in memory. 1447 EntryImpl* this_entry = it->second; 1448 this_entry->AddRef(); 1449 *entry = this_entry; 1450 return 0; 1451 } 1452 1453 STRESS_DCHECK(block_files_.IsValid(address)); 1454 1455 if (!address.SanityCheckForEntryV2()) { 1456 LOG(WARNING) << "Wrong entry address."; 1457 STRESS_NOTREACHED(); 1458 return ERR_INVALID_ADDRESS; 1459 } 1460 1461 scoped_refptr<EntryImpl> cache_entry( 1462 new EntryImpl(this, address, read_only_)); 1463 IncreaseNumRefs(); 1464 *entry = NULL; 1465 1466 TimeTicks start = TimeTicks::Now(); 1467 if (!cache_entry->entry()->Load()) 1468 return ERR_READ_FAILURE; 1469 1470 if (IsLoaded()) { 1471 CACHE_UMA(AGE_MS, "LoadTime", 0, start); 1472 } 1473 1474 if (!cache_entry->SanityCheck()) { 1475 LOG(WARNING) << "Messed up entry found."; 1476 STRESS_NOTREACHED(); 1477 return ERR_INVALID_ENTRY; 1478 } 1479 1480 STRESS_DCHECK(block_files_.IsValid( 1481 Addr(cache_entry->entry()->Data()->rankings_node))); 1482 1483 if (!cache_entry->LoadNodeAddress()) 1484 return ERR_READ_FAILURE; 1485 1486 if (!rankings_.SanityCheck(cache_entry->rankings(), false)) { 1487 STRESS_NOTREACHED(); 1488 cache_entry->SetDirtyFlag(0); 1489 // Don't remove this from the list (it is not linked properly). Instead, 1490 // break the link back to the entry because it is going away, and leave the 1491 // rankings node to be deleted if we find it through a list. 1492 rankings_.SetContents(cache_entry->rankings(), 0); 1493 } else if (!rankings_.DataSanityCheck(cache_entry->rankings(), false)) { 1494 STRESS_NOTREACHED(); 1495 cache_entry->SetDirtyFlag(0); 1496 rankings_.SetContents(cache_entry->rankings(), address.value()); 1497 } 1498 1499 if (!cache_entry->DataSanityCheck()) { 1500 LOG(WARNING) << "Messed up entry found."; 1501 cache_entry->SetDirtyFlag(0); 1502 cache_entry->FixForDelete(); 1503 } 1504 1505 // Prevent overwriting the dirty flag on the destructor. 1506 cache_entry->SetDirtyFlag(GetCurrentEntryId()); 1507 1508 if (cache_entry->dirty()) { 1509 Trace("Dirty entry 0x%p 0x%x", reinterpret_cast<void*>(cache_entry.get()), 1510 address.value()); 1511 } 1512 1513 open_entries_[address.value()] = cache_entry.get(); 1514 1515 cache_entry->BeginLogging(net_log_, false); 1516 cache_entry.swap(entry); 1517 return 0; 1518} 1519 1520EntryImpl* BackendImpl::MatchEntry(const std::string& key, uint32 hash, 1521 bool find_parent, Addr entry_addr, 1522 bool* match_error) { 1523 Addr address(data_->table[hash & mask_]); 1524 scoped_refptr<EntryImpl> cache_entry, parent_entry; 1525 EntryImpl* tmp = NULL; 1526 bool found = false; 1527 std::set<CacheAddr> visited; 1528 *match_error = false; 1529 1530 for (;;) { 1531 if (disabled_) 1532 break; 1533 1534 if (visited.find(address.value()) != visited.end()) { 1535 // It's possible for a buggy version of the code to write a loop. Just 1536 // break it. 1537 Trace("Hash collision loop 0x%x", address.value()); 1538 address.set_value(0); 1539 parent_entry->SetNextAddress(address); 1540 } 1541 visited.insert(address.value()); 1542 1543 if (!address.is_initialized()) { 1544 if (find_parent) 1545 found = true; 1546 break; 1547 } 1548 1549 int error = NewEntry(address, &tmp); 1550 cache_entry.swap(&tmp); 1551 1552 if (error || cache_entry->dirty()) { 1553 // This entry is dirty on disk (it was not properly closed): we cannot 1554 // trust it. 1555 Addr child(0); 1556 if (!error) 1557 child.set_value(cache_entry->GetNextAddress()); 1558 1559 if (parent_entry.get()) { 1560 parent_entry->SetNextAddress(child); 1561 parent_entry = NULL; 1562 } else { 1563 data_->table[hash & mask_] = child.value(); 1564 } 1565 1566 Trace("MatchEntry dirty %d 0x%x 0x%x", find_parent, entry_addr.value(), 1567 address.value()); 1568 1569 if (!error) { 1570 // It is important to call DestroyInvalidEntry after removing this 1571 // entry from the table. 1572 DestroyInvalidEntry(cache_entry.get()); 1573 cache_entry = NULL; 1574 } else { 1575 Trace("NewEntry failed on MatchEntry 0x%x", address.value()); 1576 } 1577 1578 // Restart the search. 1579 address.set_value(data_->table[hash & mask_]); 1580 visited.clear(); 1581 continue; 1582 } 1583 1584 DCHECK_EQ(hash & mask_, cache_entry->entry()->Data()->hash & mask_); 1585 if (cache_entry->IsSameEntry(key, hash)) { 1586 if (!cache_entry->Update()) 1587 cache_entry = NULL; 1588 found = true; 1589 if (find_parent && entry_addr.value() != address.value()) { 1590 Trace("Entry not on the index 0x%x", address.value()); 1591 *match_error = true; 1592 parent_entry = NULL; 1593 } 1594 break; 1595 } 1596 if (!cache_entry->Update()) 1597 cache_entry = NULL; 1598 parent_entry = cache_entry; 1599 cache_entry = NULL; 1600 if (!parent_entry.get()) 1601 break; 1602 1603 address.set_value(parent_entry->GetNextAddress()); 1604 } 1605 1606 if (parent_entry.get() && (!find_parent || !found)) 1607 parent_entry = NULL; 1608 1609 if (find_parent && entry_addr.is_initialized() && !cache_entry.get()) { 1610 *match_error = true; 1611 parent_entry = NULL; 1612 } 1613 1614 if (cache_entry.get() && (find_parent || !found)) 1615 cache_entry = NULL; 1616 1617 find_parent ? parent_entry.swap(&tmp) : cache_entry.swap(&tmp); 1618 FlushIndex(); 1619 return tmp; 1620} 1621 1622// This is the actual implementation for OpenNextEntry and OpenPrevEntry. 1623EntryImpl* BackendImpl::OpenFollowingEntry(bool forward, void** iter) { 1624 if (disabled_) 1625 return NULL; 1626 1627 DCHECK(iter); 1628 1629 const int kListsToSearch = 3; 1630 scoped_refptr<EntryImpl> entries[kListsToSearch]; 1631 scoped_ptr<Rankings::Iterator> iterator( 1632 reinterpret_cast<Rankings::Iterator*>(*iter)); 1633 *iter = NULL; 1634 1635 if (!iterator.get()) { 1636 iterator.reset(new Rankings::Iterator(&rankings_)); 1637 bool ret = false; 1638 1639 // Get an entry from each list. 1640 for (int i = 0; i < kListsToSearch; i++) { 1641 EntryImpl* temp = NULL; 1642 ret |= OpenFollowingEntryFromList(forward, static_cast<Rankings::List>(i), 1643 &iterator->nodes[i], &temp); 1644 entries[i].swap(&temp); // The entry was already addref'd. 1645 } 1646 if (!ret) 1647 return NULL; 1648 } else { 1649 // Get the next entry from the last list, and the actual entries for the 1650 // elements on the other lists. 1651 for (int i = 0; i < kListsToSearch; i++) { 1652 EntryImpl* temp = NULL; 1653 if (iterator->list == i) { 1654 OpenFollowingEntryFromList(forward, iterator->list, 1655 &iterator->nodes[i], &temp); 1656 } else { 1657 temp = GetEnumeratedEntry(iterator->nodes[i], 1658 static_cast<Rankings::List>(i)); 1659 } 1660 1661 entries[i].swap(&temp); // The entry was already addref'd. 1662 } 1663 } 1664 1665 int newest = -1; 1666 int oldest = -1; 1667 Time access_times[kListsToSearch]; 1668 for (int i = 0; i < kListsToSearch; i++) { 1669 if (entries[i].get()) { 1670 access_times[i] = entries[i]->GetLastUsed(); 1671 if (newest < 0) { 1672 DCHECK_LT(oldest, 0); 1673 newest = oldest = i; 1674 continue; 1675 } 1676 if (access_times[i] > access_times[newest]) 1677 newest = i; 1678 if (access_times[i] < access_times[oldest]) 1679 oldest = i; 1680 } 1681 } 1682 1683 if (newest < 0 || oldest < 0) 1684 return NULL; 1685 1686 EntryImpl* next_entry; 1687 if (forward) { 1688 next_entry = entries[newest].get(); 1689 iterator->list = static_cast<Rankings::List>(newest); 1690 } else { 1691 next_entry = entries[oldest].get(); 1692 iterator->list = static_cast<Rankings::List>(oldest); 1693 } 1694 1695 *iter = iterator.release(); 1696 next_entry->AddRef(); 1697 return next_entry; 1698} 1699 1700bool BackendImpl::OpenFollowingEntryFromList(bool forward, Rankings::List list, 1701 CacheRankingsBlock** from_entry, 1702 EntryImpl** next_entry) { 1703 if (disabled_) 1704 return false; 1705 1706 if (!new_eviction_ && Rankings::NO_USE != list) 1707 return false; 1708 1709 Rankings::ScopedRankingsBlock rankings(&rankings_, *from_entry); 1710 CacheRankingsBlock* next_block = forward ? 1711 rankings_.GetNext(rankings.get(), list) : 1712 rankings_.GetPrev(rankings.get(), list); 1713 Rankings::ScopedRankingsBlock next(&rankings_, next_block); 1714 *from_entry = NULL; 1715 1716 *next_entry = GetEnumeratedEntry(next.get(), list); 1717 if (!*next_entry) 1718 return false; 1719 1720 *from_entry = next.release(); 1721 return true; 1722} 1723 1724EntryImpl* BackendImpl::GetEnumeratedEntry(CacheRankingsBlock* next, 1725 Rankings::List list) { 1726 if (!next || disabled_) 1727 return NULL; 1728 1729 EntryImpl* entry; 1730 int rv = NewEntry(Addr(next->Data()->contents), &entry); 1731 if (rv) { 1732 STRESS_NOTREACHED(); 1733 rankings_.Remove(next, list, false); 1734 if (rv == ERR_INVALID_ADDRESS) { 1735 // There is nothing linked from the index. Delete the rankings node. 1736 DeleteBlock(next->address(), true); 1737 } 1738 return NULL; 1739 } 1740 1741 if (entry->dirty()) { 1742 // We cannot trust this entry. 1743 InternalDoomEntry(entry); 1744 entry->Release(); 1745 return NULL; 1746 } 1747 1748 if (!entry->Update()) { 1749 STRESS_NOTREACHED(); 1750 entry->Release(); 1751 return NULL; 1752 } 1753 1754 // Note that it is unfortunate (but possible) for this entry to be clean, but 1755 // not actually the real entry. In other words, we could have lost this entry 1756 // from the index, and it could have been replaced with a newer one. It's not 1757 // worth checking that this entry is "the real one", so we just return it and 1758 // let the enumeration continue; this entry will be evicted at some point, and 1759 // the regular path will work with the real entry. With time, this problem 1760 // will disasappear because this scenario is just a bug. 1761 1762 // Make sure that we save the key for later. 1763 entry->GetKey(); 1764 1765 return entry; 1766} 1767 1768EntryImpl* BackendImpl::ResurrectEntry(EntryImpl* deleted_entry) { 1769 if (ENTRY_NORMAL == deleted_entry->entry()->Data()->state) { 1770 deleted_entry->Release(); 1771 stats_.OnEvent(Stats::CREATE_MISS); 1772 Trace("create entry miss "); 1773 return NULL; 1774 } 1775 1776 // We are attempting to create an entry and found out that the entry was 1777 // previously deleted. 1778 1779 eviction_.OnCreateEntry(deleted_entry); 1780 entry_count_++; 1781 1782 stats_.OnEvent(Stats::RESURRECT_HIT); 1783 Trace("Resurrect entry hit "); 1784 return deleted_entry; 1785} 1786 1787void BackendImpl::DestroyInvalidEntry(EntryImpl* entry) { 1788 LOG(WARNING) << "Destroying invalid entry."; 1789 Trace("Destroying invalid entry 0x%p", entry); 1790 1791 entry->SetPointerForInvalidEntry(GetCurrentEntryId()); 1792 1793 eviction_.OnDoomEntry(entry); 1794 entry->InternalDoom(); 1795 1796 if (!new_eviction_) 1797 DecreaseNumEntries(); 1798 stats_.OnEvent(Stats::INVALID_ENTRY); 1799} 1800 1801void BackendImpl::AddStorageSize(int32 bytes) { 1802 data_->header.num_bytes += bytes; 1803 DCHECK_GE(data_->header.num_bytes, 0); 1804} 1805 1806void BackendImpl::SubstractStorageSize(int32 bytes) { 1807 data_->header.num_bytes -= bytes; 1808 DCHECK_GE(data_->header.num_bytes, 0); 1809} 1810 1811void BackendImpl::IncreaseNumRefs() { 1812 num_refs_++; 1813 if (max_refs_ < num_refs_) 1814 max_refs_ = num_refs_; 1815} 1816 1817void BackendImpl::DecreaseNumRefs() { 1818 DCHECK(num_refs_); 1819 num_refs_--; 1820 1821 if (!num_refs_ && disabled_) 1822 base::MessageLoop::current()->PostTask( 1823 FROM_HERE, base::Bind(&BackendImpl::RestartCache, GetWeakPtr(), true)); 1824} 1825 1826void BackendImpl::IncreaseNumEntries() { 1827 data_->header.num_entries++; 1828 DCHECK_GT(data_->header.num_entries, 0); 1829} 1830 1831void BackendImpl::DecreaseNumEntries() { 1832 data_->header.num_entries--; 1833 if (data_->header.num_entries < 0) { 1834 NOTREACHED(); 1835 data_->header.num_entries = 0; 1836 } 1837} 1838 1839void BackendImpl::LogStats() { 1840 StatsItems stats; 1841 GetStats(&stats); 1842 1843 for (size_t index = 0; index < stats.size(); index++) 1844 VLOG(1) << stats[index].first << ": " << stats[index].second; 1845} 1846 1847void BackendImpl::ReportStats() { 1848 CACHE_UMA(COUNTS, "Entries", 0, data_->header.num_entries); 1849 1850 int current_size = data_->header.num_bytes / (1024 * 1024); 1851 int max_size = max_size_ / (1024 * 1024); 1852 int hit_ratio_as_percentage = stats_.GetHitRatio(); 1853 1854 CACHE_UMA(COUNTS_10000, "Size2", 0, current_size); 1855 // For any bin in HitRatioBySize2, the hit ratio of caches of that size is the 1856 // ratio of that bin's total count to the count in the same bin in the Size2 1857 // histogram. 1858 if (base::RandInt(0, 99) < hit_ratio_as_percentage) 1859 CACHE_UMA(COUNTS_10000, "HitRatioBySize2", 0, current_size); 1860 CACHE_UMA(COUNTS_10000, "MaxSize2", 0, max_size); 1861 if (!max_size) 1862 max_size++; 1863 CACHE_UMA(PERCENTAGE, "UsedSpace", 0, current_size * 100 / max_size); 1864 1865 CACHE_UMA(COUNTS_10000, "AverageOpenEntries2", 0, 1866 static_cast<int>(stats_.GetCounter(Stats::OPEN_ENTRIES))); 1867 CACHE_UMA(COUNTS_10000, "MaxOpenEntries2", 0, 1868 static_cast<int>(stats_.GetCounter(Stats::MAX_ENTRIES))); 1869 stats_.SetCounter(Stats::MAX_ENTRIES, 0); 1870 1871 CACHE_UMA(COUNTS_10000, "TotalFatalErrors", 0, 1872 static_cast<int>(stats_.GetCounter(Stats::FATAL_ERROR))); 1873 CACHE_UMA(COUNTS_10000, "TotalDoomCache", 0, 1874 static_cast<int>(stats_.GetCounter(Stats::DOOM_CACHE))); 1875 CACHE_UMA(COUNTS_10000, "TotalDoomRecentEntries", 0, 1876 static_cast<int>(stats_.GetCounter(Stats::DOOM_RECENT))); 1877 stats_.SetCounter(Stats::FATAL_ERROR, 0); 1878 stats_.SetCounter(Stats::DOOM_CACHE, 0); 1879 stats_.SetCounter(Stats::DOOM_RECENT, 0); 1880 1881 int age = (Time::Now() - 1882 Time::FromInternalValue(data_->header.create_time)).InHours(); 1883 if (age) 1884 CACHE_UMA(HOURS, "FilesAge", 0, age); 1885 1886 int64 total_hours = stats_.GetCounter(Stats::TIMER) / 120; 1887 if (!data_->header.create_time || !data_->header.lru.filled) { 1888 int cause = data_->header.create_time ? 0 : 1; 1889 if (!data_->header.lru.filled) 1890 cause |= 2; 1891 CACHE_UMA(CACHE_ERROR, "ShortReport", 0, cause); 1892 CACHE_UMA(HOURS, "TotalTimeNotFull", 0, static_cast<int>(total_hours)); 1893 return; 1894 } 1895 1896 // This is an up to date client that will report FirstEviction() data. After 1897 // that event, start reporting this: 1898 1899 CACHE_UMA(HOURS, "TotalTime", 0, static_cast<int>(total_hours)); 1900 // For any bin in HitRatioByTotalTime, the hit ratio of caches of that total 1901 // time is the ratio of that bin's total count to the count in the same bin in 1902 // the TotalTime histogram. 1903 if (base::RandInt(0, 99) < hit_ratio_as_percentage) 1904 CACHE_UMA(HOURS, "HitRatioByTotalTime", 0, implicit_cast<int>(total_hours)); 1905 1906 int64 use_hours = stats_.GetCounter(Stats::LAST_REPORT_TIMER) / 120; 1907 stats_.SetCounter(Stats::LAST_REPORT_TIMER, stats_.GetCounter(Stats::TIMER)); 1908 1909 // We may see users with no use_hours at this point if this is the first time 1910 // we are running this code. 1911 if (use_hours) 1912 use_hours = total_hours - use_hours; 1913 1914 if (!use_hours || !GetEntryCount() || !data_->header.num_bytes) 1915 return; 1916 1917 CACHE_UMA(HOURS, "UseTime", 0, static_cast<int>(use_hours)); 1918 // For any bin in HitRatioByUseTime, the hit ratio of caches of that use time 1919 // is the ratio of that bin's total count to the count in the same bin in the 1920 // UseTime histogram. 1921 if (base::RandInt(0, 99) < hit_ratio_as_percentage) 1922 CACHE_UMA(HOURS, "HitRatioByUseTime", 0, implicit_cast<int>(use_hours)); 1923 CACHE_UMA(PERCENTAGE, "HitRatio", 0, hit_ratio_as_percentage); 1924 1925 int64 trim_rate = stats_.GetCounter(Stats::TRIM_ENTRY) / use_hours; 1926 CACHE_UMA(COUNTS, "TrimRate", 0, static_cast<int>(trim_rate)); 1927 1928 int avg_size = data_->header.num_bytes / GetEntryCount(); 1929 CACHE_UMA(COUNTS, "EntrySize", 0, avg_size); 1930 CACHE_UMA(COUNTS, "EntriesFull", 0, data_->header.num_entries); 1931 1932 CACHE_UMA(PERCENTAGE, "IndexLoad", 0, 1933 data_->header.num_entries * 100 / (mask_ + 1)); 1934 1935 int large_entries_bytes = stats_.GetLargeEntriesSize(); 1936 int large_ratio = large_entries_bytes * 100 / data_->header.num_bytes; 1937 CACHE_UMA(PERCENTAGE, "LargeEntriesRatio", 0, large_ratio); 1938 1939 if (new_eviction_) { 1940 CACHE_UMA(PERCENTAGE, "ResurrectRatio", 0, stats_.GetResurrectRatio()); 1941 CACHE_UMA(PERCENTAGE, "NoUseRatio", 0, 1942 data_->header.lru.sizes[0] * 100 / data_->header.num_entries); 1943 CACHE_UMA(PERCENTAGE, "LowUseRatio", 0, 1944 data_->header.lru.sizes[1] * 100 / data_->header.num_entries); 1945 CACHE_UMA(PERCENTAGE, "HighUseRatio", 0, 1946 data_->header.lru.sizes[2] * 100 / data_->header.num_entries); 1947 CACHE_UMA(PERCENTAGE, "DeletedRatio", 0, 1948 data_->header.lru.sizes[4] * 100 / data_->header.num_entries); 1949 } 1950 1951 stats_.ResetRatios(); 1952 stats_.SetCounter(Stats::TRIM_ENTRY, 0); 1953 1954 if (cache_type_ == net::DISK_CACHE) 1955 block_files_.ReportStats(); 1956} 1957 1958void BackendImpl::UpgradeTo2_1() { 1959 // 2.1 is basically the same as 2.0, except that new fields are actually 1960 // updated by the new eviction algorithm. 1961 DCHECK(0x20000 == data_->header.version); 1962 data_->header.version = 0x20001; 1963 data_->header.lru.sizes[Rankings::NO_USE] = data_->header.num_entries; 1964} 1965 1966bool BackendImpl::CheckIndex() { 1967 DCHECK(data_); 1968 1969 size_t current_size = index_->GetLength(); 1970 if (current_size < sizeof(Index)) { 1971 LOG(ERROR) << "Corrupt Index file"; 1972 return false; 1973 } 1974 1975 if (new_eviction_) { 1976 // We support versions 2.0 and 2.1, upgrading 2.0 to 2.1. 1977 if (kIndexMagic != data_->header.magic || 1978 kCurrentVersion >> 16 != data_->header.version >> 16) { 1979 LOG(ERROR) << "Invalid file version or magic"; 1980 return false; 1981 } 1982 if (kCurrentVersion == data_->header.version) { 1983 // We need file version 2.1 for the new eviction algorithm. 1984 UpgradeTo2_1(); 1985 } 1986 } else { 1987 if (kIndexMagic != data_->header.magic || 1988 kCurrentVersion != data_->header.version) { 1989 LOG(ERROR) << "Invalid file version or magic"; 1990 return false; 1991 } 1992 } 1993 1994 if (!data_->header.table_len) { 1995 LOG(ERROR) << "Invalid table size"; 1996 return false; 1997 } 1998 1999 if (current_size < GetIndexSize(data_->header.table_len) || 2000 data_->header.table_len & (kBaseTableLen - 1)) { 2001 LOG(ERROR) << "Corrupt Index file"; 2002 return false; 2003 } 2004 2005 AdjustMaxCacheSize(data_->header.table_len); 2006 2007#if !defined(NET_BUILD_STRESS_CACHE) 2008 if (data_->header.num_bytes < 0 || 2009 (max_size_ < kint32max - kDefaultCacheSize && 2010 data_->header.num_bytes > max_size_ + kDefaultCacheSize)) { 2011 LOG(ERROR) << "Invalid cache (current) size"; 2012 return false; 2013 } 2014#endif 2015 2016 if (data_->header.num_entries < 0) { 2017 LOG(ERROR) << "Invalid number of entries"; 2018 return false; 2019 } 2020 2021 if (!mask_) 2022 mask_ = data_->header.table_len - 1; 2023 2024 // Load the table into memory. 2025 return index_->Preload(); 2026} 2027 2028int BackendImpl::CheckAllEntries() { 2029 int num_dirty = 0; 2030 int num_entries = 0; 2031 DCHECK(mask_ < kuint32max); 2032 for (unsigned int i = 0; i <= mask_; i++) { 2033 Addr address(data_->table[i]); 2034 if (!address.is_initialized()) 2035 continue; 2036 for (;;) { 2037 EntryImpl* tmp; 2038 int ret = NewEntry(address, &tmp); 2039 if (ret) { 2040 STRESS_NOTREACHED(); 2041 return ret; 2042 } 2043 scoped_refptr<EntryImpl> cache_entry; 2044 cache_entry.swap(&tmp); 2045 2046 if (cache_entry->dirty()) 2047 num_dirty++; 2048 else if (CheckEntry(cache_entry.get())) 2049 num_entries++; 2050 else 2051 return ERR_INVALID_ENTRY; 2052 2053 DCHECK_EQ(i, cache_entry->entry()->Data()->hash & mask_); 2054 address.set_value(cache_entry->GetNextAddress()); 2055 if (!address.is_initialized()) 2056 break; 2057 } 2058 } 2059 2060 Trace("CheckAllEntries End"); 2061 if (num_entries + num_dirty != data_->header.num_entries) { 2062 LOG(ERROR) << "Number of entries " << num_entries << " " << num_dirty << 2063 " " << data_->header.num_entries; 2064 DCHECK_LT(num_entries, data_->header.num_entries); 2065 return ERR_NUM_ENTRIES_MISMATCH; 2066 } 2067 2068 return num_dirty; 2069} 2070 2071bool BackendImpl::CheckEntry(EntryImpl* cache_entry) { 2072 bool ok = block_files_.IsValid(cache_entry->entry()->address()); 2073 ok = ok && block_files_.IsValid(cache_entry->rankings()->address()); 2074 EntryStore* data = cache_entry->entry()->Data(); 2075 for (size_t i = 0; i < arraysize(data->data_addr); i++) { 2076 if (data->data_addr[i]) { 2077 Addr address(data->data_addr[i]); 2078 if (address.is_block_file()) 2079 ok = ok && block_files_.IsValid(address); 2080 } 2081 } 2082 2083 return ok && cache_entry->rankings()->VerifyHash(); 2084} 2085 2086int BackendImpl::MaxBuffersSize() { 2087 static int64 total_memory = base::SysInfo::AmountOfPhysicalMemory(); 2088 static bool done = false; 2089 2090 if (!done) { 2091 const int kMaxBuffersSize = 30 * 1024 * 1024; 2092 2093 // We want to use up to 2% of the computer's memory. 2094 total_memory = total_memory * 2 / 100; 2095 if (total_memory > kMaxBuffersSize || total_memory <= 0) 2096 total_memory = kMaxBuffersSize; 2097 2098 done = true; 2099 } 2100 2101 return static_cast<int>(total_memory); 2102} 2103 2104} // namespace disk_cache 2105