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Unified Diff: net/disk_cache/v3/index_table.cc

Issue 15203004: Disk cache: Reference CL for the implementation of file format version 3. (Closed) Base URL: svn://svn.chromium.org/chrome/trunk/src/
Patch Set: Created 7 years, 7 months ago
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Index: net/disk_cache/v3/index_table.cc
===================================================================
--- net/disk_cache/v3/index_table.cc (revision 0)
+++ net/disk_cache/v3/index_table.cc (revision 0)
@@ -0,0 +1,717 @@
+// Copyright (c) 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "net/disk_cache/v3/index_table.h"
+
+#include <set>
+
+#include "net/base/net_errors.h"
+#include "net/disk_cache/disk_cache.h"
+#include "net/disk_cache/v3/backend_impl_v3.h"
+#include "net/disk_cache/v3/backend_work_item.h"
+
+using base::Time;
+using base::TimeDelta;
+using disk_cache::CellId;
+using disk_cache::CellList;
+using disk_cache::IndexCell;
+using disk_cache::IndexIterator;
+
+namespace {
+
+const uint32 kMaxAddress = 1 << 22;
+const uint32 kBasicMask = 0xFFFF;
+
+int GetSum(const IndexCell& cell) {
+ return cell.timestamp_and_sum >> 6;
+}
+
+// This is a quite peculiar way to calculate the sum, so it will not match if
+// compared a gainst a pure 2 bit, modulo 2 sum.
+int CalculateSum(const IndexCell& cell) {
+ uint32* word = bit_cast<uint32*>(&cell);
+ uint32 result = word[0] + word[1];
+ result += result >> 16;
+ result += (result >> 8) + (cell.timestamp_and_hash & 0x3f);
+ result += result >> 4;
+ result += result >> 2;
+ return result & 3;
+}
+
+bool SanityCheck(const IndexCell& cell) {
+ if (GetSum(cell) != CalculateSum(cell))
+ return false;
+
+ if (cell.state > disk_cache::ENTRY_USED ||
+ cell.group == disk_cache::ENTRY_RESERVED ||
+ cell.group > disk_cache::ENTRY_EVICTED) {
+ return false;
+ }
+
+ return true;
+}
+
+inline bool HashMatches(uint32 stored, uint32 value, int extra_bits) {
+ return (stored >> extra_bits) == (value >> (14 + extra_bits));
+}
+
+inline bool MisplacedHash(uint32 stored, uint32 value, int extra_bits) {
+ if (!extra_bits)
+ return false;
+ uint32 mask = (1 << extra_bits) - 1;
+ return (stored & mask) != ((value >> 14) & mask);
+}
+
+inline int GetNextBucket(int min_bucket_id, int max_bucket_id,
+ disk_cache::IndexBucket* table,
+ disk_cache::IndexBucket** bucket) {
+ if (!(*bucket)->next)
+ return 0;
+
+ int bucket_id = (*bucket)->next / 4;
+ if (bucket_id < min_bucket_id || bucket_id > max_bucket_id) {
+ (*bucket)->next = 0;
+ return 0;
+ }
+ *bucket = &table[bucket_id - min_bucket_id];
+ return bucket_id;
+}
+
+void UpdateListWithCell(int bucket_hash, const IndexCell& cell, CellList* list,
+ int* list_time) {
+ if (!list)
+ return;
+
+ int time = disk_cache::EntryCell::GetTimestamp(cell);
+ if (time < *list_time) {
+ *list_time = time;
+ list->clear();
+ }
+ if (time == *list_time) {
+ CellId cell_id = {
+ (disk_cache::EntryCell::GetHash(cell) << 14) + bucket_hash,
+ disk_cache::Addr::FromEntryAddress(cell.address)
+ };
+ list->push_back(cell_id);
+ }
+}
+
+void GetNewestFromBucket(disk_cache::IndexBucket* bucket, int bucket_hash,
+ int limit_time, IndexIterator* iterator) {
+ for (int i = 0; i < 4; i++) {
+ IndexCell& current_cell = bucket->cells[i];
+ if (!current_cell.address)
+ continue;
+ DCHECK(SanityCheck(current_cell));
+ if (!disk_cache::EntryCell::IsNormalState(current_cell))
+ continue;
+
+ int time = disk_cache::EntryCell::GetTimestamp(current_cell);
+ switch (current_cell.group) {
+ case disk_cache::ENTRY_NO_USE:
+ case disk_cache::ENTRY_LOW_USE:
+ case disk_cache::ENTRY_HIGH_USE:
+ if (iterator->forward && time >= limit_time)
+ continue;
+ if (!iterator->forward && time <= limit_time)
+ continue;
+
+ if ((iterator->forward && time > iterator->timestamp) ||
+ (!iterator->forward && time < iterator->timestamp)) {
+ iterator->timestamp = time;
+ iterator->cells.clear();
+ }
+ if (time == iterator->timestamp) {
+ CellId cell_id = {
+ (disk_cache::EntryCell::GetHash(current_cell) << 14) + bucket_hash,
+ disk_cache::Addr::FromEntryAddress(current_cell.address)
+ };
+ iterator->cells.push_back(cell_id);
+ }
+ }
+ }
+}
+
+} // namespace
+
+namespace disk_cache {
+
+EntryCell::EntryCell() : cell_id_(0), hash_(0) {
+ cell_.Clear();
+}
+
+EntryCell::EntryCell(int32 cell_id, uint32 hash, Addr address)
+ : cell_id_(cell_id),
+ hash_(hash) {
+ DCHECK(ValidAddress(address) || !address.value());
+
+ cell_.Clear();
+ cell_.address = address.value() & 0xFFFFFF;
+ cell_.state = ENTRY_NEW;
+ cell_.group = ENTRY_NO_USE;
+ cell_.hash = (hash >> 16) & kBasicMask;
+ cell_.timestamp_and_hash = (hash >> 14) & 3;
+}
+
+EntryCell::EntryCell(int32 cell_id, uint32 hash, const IndexCell& cell)
+ : cell_id_(cell_id),
+ hash_(hash),
+ cell_(cell) {
+}
+
+EntryCell::~EntryCell() {
+}
+
+Addr EntryCell::GetAddress() const {
+ if (group() == ENTRY_EVICTED)
+ return Addr::FromEvictedAddress(cell_.address);
+ else
+ return Addr::FromEntryAddress(cell_.address);
+}
+
+int EntryCell::GetTimestamp() const {
+ return GetTimestamp(cell_);
+}
+
+void EntryCell::set_reuse(int count) {
+ DCHECK_LT(count, 16);
+ DCHECK_GE(count, 0);
+ cell_.reuse = count;
+}
+
+// This operation destroys (ignores) the sum.
+void EntryCell::set_timestamp(int timestamp) {
+ DCHECK_LT(timestamp, 1 << 20);
+ DCHECK_GE(timestamp, 0);
+ cell_.timestamp_and_hash = ((timestamp & 0x3fff) << 2) +
+ (cell_.timestamp_and_hash & 3);
+ cell_.timestamp_and_sum = (timestamp >> 14) & 0x3f;
+}
+
+// Static.
+bool EntryCell::ValidAddress(Addr address) {
+ if (!address.is_initialized() ||
+ (address.file_type() != BLOCK_EVICTED &&
+ address.file_type() != BLOCK_ENTRIES)) {
+ return false;
+ }
+
+ return (address.value() & 0xF00000) < kMaxAddress;
+}
+
+// Static.
+uint32 EntryCell::GetHash(const IndexCell& cell) {
+ return (cell.hash << 2) + (cell.timestamp_and_hash & 3);
+}
+
+// Static.
+int EntryCell::GetTimestamp(const IndexCell& cell) {
+ return (cell.timestamp_and_hash >> 2) +
+ ((cell.timestamp_and_sum & 0x3f) << 14);
+}
+
+// Static.
+bool EntryCell::IsNormalState(const IndexCell& cell) {
+ EntryState state = static_cast<EntryState>(cell.state);
+ DCHECK_NE(state, ENTRY_FREE);
+ return state != ENTRY_DELETED && state != ENTRY_FIXING;
+}
+
+void EntryCell::FixSum() {
+ cell_.timestamp_and_sum = (cell_.timestamp_and_sum & 0x3f) |
+ (CalculateSum(cell_) << 6);
+}
+
+EntrySet::EntrySet() : evicted_count(0), current(0) {
+}
+
+// -----------------------------------------------------------------------
+
+IndexTable::IndexTable(BackendImplV3* backend)
+ : backend_(backend),
+ header_(NULL),
+ main_table_(NULL),
+ extra_table_(NULL) {
+}
+
+void IndexTable::Init(InitResult* params) {
+ bool growing = header_ != NULL;
+ IndexBucket* old_extra_table = NULL;
+ header_ = &params->index_bitmap->header;
+
+ if (params->main_table) {
+ if (main_table_) {
+ DCHECK_EQ(header_->table_len / kIndexTablesize,
+ backup_header_->table_len / kIndexTablesize + 1);
+ old_extra_table = extra_table_;
+ }
+ main_table_ = params->main_table;
+ }
+ DCHECK(main_table_);
+ extra_table_ = params->extra_table;
+
+ extra_bits_ = header_->table_len / kIndexTablesize - 1;
+ DCHECK_GE(extra_bits_, 0);
+ DCHECK_LE(extra_bits_, 6);
+ mask_ = ((kIndexTablesize / 4) << extra_bits_) - 1;
+
+ int num_words = (header_->table_len + 31) / 32 ;
+ bitmap_.reset(new Bitmap(params->index_bitmap->bitmap, header_->table_len,
+ num_words));
+
+ if (growing) {
+ int old_num_words = (backup_header_->table_len + 31) / 32;
+ DCHECK_GE(num_words, old_num_words);
+ scoped_ptr<uint32[]> storage(new uint32[num_words]);
+ memcpy(storage.get(), backup_bitmap_storage_.get(), old_num_words * 4);
+ memset(storage.get() + old_num_words, 0, (num_words - old_num_words) * 4);
+
+ backup_bitmap_storage_.swap(storage);
+ backup_header_->table_len = header_->table_len;
+ } else {
+ backup_bitmap_storage_.reset(params->backup_bitmap.release());
+ backup_header_.reset(params->backup_header.release());
+ }
+
+ num_words = (backup_header_->table_len + 31) / 32;
+ backup_bitmap_.reset(new Bitmap(backup_bitmap_storage_.get(),
+ backup_header_->table_len, num_words));
+ if (old_extra_table)
+ MoveCells(old_extra_table);
+}
+
+void IndexTable::Reset() {
+ header_ = NULL;
+ main_table_ = NULL;
+ extra_table_ = NULL;
+ bitmap_.reset();
+ backup_bitmap_.reset();
+ backup_header_.reset();
+ backup_bitmap_storage_.reset();
+}
+
+EntrySet IndexTable::LookupEntry(uint32 hash) {
+ EntrySet entries;
+ int bucket_id = static_cast<int>(hash & mask_);
+ IndexBucket* bucket = &main_table_[bucket_id];
+ for (;;) {
+ for (int i = 0; i < 4; i++) {
+ IndexCell* current_cell = &bucket->cells[i];
+ if (!current_cell->address)
+ continue;
+ if (!SanityCheck(*current_cell)) {
+ NOTREACHED();
+ current_cell->Clear();
+ continue;
+ }
+ int cell_id = bucket_id * 4 + i;
+ if (MisplacedHash(EntryCell::GetHash(*current_cell), hash, extra_bits_)) {
+ HandleMisplacedCell(current_cell, cell_id, hash & mask_);
+ } else if (HashMatches(EntryCell::GetHash(*current_cell), hash,
+ extra_bits_)) {
+ CheckState(current_cell, cell_id);
+ if (current_cell->state != ENTRY_DELETED) {
+ EntryCell entry_cell(cell_id, hash, *current_cell);
+ entries.cells.push_back(entry_cell);
+ if (current_cell->group == ENTRY_EVICTED)
+ entries.evicted_count++;
+ }
+ }
+ }
+ bucket_id = GetNextBucket(mask_ + 1, header()->max_bucket, extra_table_,
+ &bucket);
+ if (!bucket_id)
+ break;
+ }
+ return entries;
+}
+
+EntryCell IndexTable::CreateEntryCell(uint32 hash, Addr address) {
+ DCHECK(EntryCell::ValidAddress(address));
+
+ int bucket_id = static_cast<int>(hash & mask_);
+ int cell_id = 0;
+ IndexBucket* bucket = &main_table_[bucket_id];
+ IndexCell* current_cell = NULL;
+ bool found = false;
+ for (; !found;) {
+ for (int i = 0; i < 4 && !found; i++) {
+ current_cell = &bucket->cells[i];
+ if (!current_cell->address) {
+ cell_id = bucket_id * 4 + i;
+ found = true;
+ }
+ }
+ if (found)
+ break;
+ bucket_id = GetNextBucket(mask_ + 1, header()->max_bucket, extra_table_,
+ &bucket);
+ if (!bucket_id)
+ break;
+ }
+
+ if (!found) {
+ bucket_id = NewExtraBucket();
+ if (bucket_id) {
+ cell_id = bucket_id * 4;
+ bucket->next = cell_id;
+ found = true;
+ } else {
+ // address 0 is a reserved value, and the caller interprets it as invalid.
+ address.set_value(0);
+ }
+ }
+
+ EntryCell entry_cell(cell_id, hash, address);
+ if (address.file_type() == BLOCK_EVICTED)
+ entry_cell.set_group(ENTRY_EVICTED);
+ else
+ entry_cell.set_group(ENTRY_NO_USE);
+ Save(&entry_cell);
+
+ if (found) {
+ bitmap_->Set(cell_id, true);
+ backup_bitmap_->Set(cell_id, true);
+ header()->used_cells++;
+ }
+
+ return entry_cell;
+}
+
+bool IndexTable::SetSate(uint32 hash, Addr address, EntryState state) {
+ EntryCell cell = FindEntryCellImpl(hash, address, state == ENTRY_FREE);
+ if (!cell.IsValid())
+ return false;
+
+ if (state == ENTRY_DELETED) {
+ bitmap_->Set(cell.cell_id(), false);
+ backup_bitmap_->Set(cell.cell_id(), false);
+ } else if (state == ENTRY_FREE) {
+ DCHECK_EQ(ENTRY_DELETED, cell.state());
+ cell.Clear();
+ Write(cell);
+ header()->used_cells--;
+ return true;
+ }
+ cell.set_state(state);
+
+ Save(&cell);
+ return true;
+}
+
+int IndexTable::GetTimestamp(Time time) {
+ TimeDelta delta = time - Time::FromInternalValue(header_->base_time);
+ return std::max(delta.InMinutes(), 0);
+}
+
+void IndexTable::UpdateTime(uint32 hash, Addr address) {
+ EntryCell cell = FindEntryCell(hash, address);
+ if (!cell.IsValid())
+ return;
+
+ int minutes = GetTimestamp(backend_->GetCurrentTime());
+
+ // Keep about 3 months of headroom.
+ const int kMaxTimestamp = (1 << 20) - 60 * 24 * 90;
+ if (minutes > kMaxTimestamp) {
+ // TODO(rvargas):
+ // Update header->old_time and trigger a timer
+ // Rebaseline timestamps and don't update sums
+ // Start a timer (about 2 backups)
+ // fix all ckecksums and trigger another timer
+ // update header->old_time because rebaseline is done.
+ minutes = std::min(minutes, (1 << 20) - 1);
+ }
+
+ cell.set_timestamp(minutes);
+ Save(&cell);
+}
+
+EntryCell IndexTable::FindEntryCell(uint32 hash, Addr address) {
+ return FindEntryCellImpl(hash, address, false);
+}
+
+void IndexTable::Save(EntryCell* cell) {
+ cell->FixSum();
+ Write(*cell);
+}
+
+void IndexTable::GetOldest(CellList* no_use, CellList* low_use,
+ CellList* high_use) {
+ header_->num_no_use_entries = 0;
+ header_->num_low_use_entries = 0;
+ header_->num_high_use_entries = 0;
+ header_->num_evicted_entries = 0;
+
+ int no_use_time = kint32max;
+ int low_use_time = kint32max;
+ int high_use_time = kint32max;
+ for (int i = 0; i < static_cast<int32>(mask_ + 1); i++) {
+ int bucket_id = i;
+ IndexBucket* bucket = &main_table_[i];
+ for (;;) {
+ GetOldestFromBucket(bucket, i, no_use, &no_use_time, low_use,
+ &low_use_time, high_use, &high_use_time);
+
+ bucket_id = GetNextBucket(mask_ + 1, header()->max_bucket, extra_table_,
+ &bucket);
+ if (!bucket_id)
+ break;
+ }
+ }
+ header_->num_entries = header_->num_no_use_entries +
+ header_->num_low_use_entries +
+ header_->num_high_use_entries +
+ header_->num_evicted_entries;
+}
+
+bool IndexTable::GetNextCells(IndexIterator* iterator) {
+ int current_time = iterator->timestamp;
+ size_t initial_size = iterator->cells.size();
+ iterator->timestamp = iterator->forward ? 0 : kint32max;
+
+ for (int i = 0; i < static_cast<int32>(mask_ + 1); i++) {
+ int bucket_id = i;
+ IndexBucket* bucket = &main_table_[i];
+ for (;;) {
+ GetNewestFromBucket(bucket, i, current_time, iterator);
+
+ bucket_id = GetNextBucket(mask_ + 1, header()->max_bucket, extra_table_,
+ &bucket);
+ if (!bucket_id)
+ break;
+ }
+ }
+ return initial_size != iterator->cells.size();
+}
+
+// -----------------------------------------------------------------------
+
+EntryCell IndexTable::FindEntryCellImpl(uint32 hash, Addr address,
+ bool allow_deleted) {
+ int bucket_id = static_cast<int>(hash & mask_);
+ IndexBucket* bucket = &main_table_[bucket_id];
+ for (;;) {
+ for (int i = 0; i < 4; i++) {
+ IndexCell* current_cell = &bucket->cells[i];
+ if (!current_cell->address)
+ continue;
+ DCHECK(SanityCheck(*current_cell));
+ if (EntryCell::GetHash(*current_cell) == (hash >> 14)) {
+ // We have a match.
+ int cell_id = bucket_id * 4 + i;
+ EntryCell entry_cell(cell_id, hash, *current_cell);
+ if (entry_cell.GetAddress() != address)
+ continue;
+
+ if (!allow_deleted && entry_cell.state() == ENTRY_DELETED)
+ continue;
+
+ return entry_cell;
+ }
+ }
+ bucket_id = GetNextBucket(mask_ + 1, header()->max_bucket, extra_table_,
+ &bucket);
+ if (!bucket_id)
+ break;
+ }
+ return EntryCell();
+}
+
+void IndexTable::CheckState(IndexCell* cell, int32 cell_id) {
+ if (cell->state != ENTRY_FIXING) {
+ bool present = ((cell->state & 3) != 0); // Look at the last two bits.
+ if (present != bitmap_->Get(cell_id) ||
+ present != backup_bitmap_->Get(cell_id)) {
+ // There's a mismatch.
+ if (cell->state == ENTRY_DELETED) {
+ // We were in the process of deleting this entry. Finish now.
+ backend_->DeleteCell(cell, cell_id);
+ } else {
+ cell->state = ENTRY_FIXING;
+ }
+ }
+ }
+
+ if (cell->state == ENTRY_FIXING)
+ backend_->FixCell(cell, cell_id);
+}
+
+void IndexTable::Write(const EntryCell& cell) {
+ if (!cell.IsValid())
+ return;
+
+ IndexBucket* bucket = NULL;
+ int bucket_id = cell.cell_id() / 4;
+ if (bucket_id < static_cast<int32>(mask_ + 1)) {
+ bucket = &main_table_[bucket_id];
+ } else {
+ DCHECK_LE(bucket_id, header()->max_bucket);
+ bucket = &extra_table_[bucket_id - (mask_ + 1)];
+ }
+ memcpy(&bucket->cells[cell.cell_id() % 4], &cell.cell(), sizeof(IndexCell));
+}
+
+int IndexTable::NewExtraBucket() {
+ if (header()->table_len - header()->max_bucket * 4 < kNumExtraBlocks)
+ backend_->GrowIndex();
+
+ if (header()->max_bucket * 4 == header()->table_len - 4)
+ return 0;
+
+ header()->max_bucket++;
+ return header()->max_bucket;
+}
+
+void IndexTable::GetOldestFromBucket(IndexBucket* bucket, int bucket_hash,
+ CellList* no_use, int* no_use_time,
+ CellList* low_use, int* low_use_time,
+ CellList* high_use, int* high_use_time) {
+ for (int i = 0; i < 4; i++) {
+ IndexCell& current_cell = bucket->cells[i];
+ if (!current_cell.address)
+ continue;
+ DCHECK(SanityCheck(current_cell));
+ if (!EntryCell::IsNormalState(current_cell))
+ continue;
+
+ int time = EntryCell::GetTimestamp(current_cell);
+ switch (current_cell.group) {
+ case ENTRY_NO_USE:
+ UpdateListWithCell(bucket_hash, current_cell, no_use, no_use_time);
+ header_->num_no_use_entries++;
+ break;
+ case ENTRY_LOW_USE:
+ UpdateListWithCell(bucket_hash, current_cell, low_use, low_use_time);
+ header_->num_low_use_entries++;
+ break;
+ case ENTRY_HIGH_USE:
+ UpdateListWithCell(bucket_hash, current_cell, high_use, high_use_time);
+ header_->num_high_use_entries++;
+ break;
+ case ENTRY_EVICTED:
+ header_->num_evicted_entries++;
+ break;
+ default:
+ NOTREACHED();
+ }
+ }
+}
+
+void IndexTable::MoveCells(IndexBucket* old_extra_table) {
+ int max_hash = (mask_ + 1) / 2;
+ int max_bucket = header()->max_bucket;
+ header()->max_bucket = mask_;
+
+ // A cell stores the upper 18 bits of the hash (h >> 14). If the table is say
+ // 8 times the original size (growing from 4x), the bit that we are interested
+ // in would be the 3rd bit of the stored value, in other words multiplir >> 1.
+ uint32 new_bit = ((mask_ + 1) * 4 / kIndexTablesize) >> 1;
+
+ for (int i = 0; i < max_hash; i++) {
+ int bucket_id = i;
+ IndexBucket* bucket = &main_table_[i];
+ for (;;) {
+ for (int j = 0; j < 4; j++) {
+ IndexCell& current_cell = bucket->cells[j];
+ if (!current_cell.address)
+ continue;
+ DCHECK(SanityCheck(current_cell));
+ if (bucket_id == i) {
+ if (EntryCell::GetHash(current_cell) & new_bit) {
+ // Move this cell to the upper half of the table.
+ MoveSingleCell(&current_cell, bucket_id * 4 + j, i, true);
+ }
+ } else {
+ // All cells on extra buckets have to move.
+ MoveSingleCell(&current_cell, bucket_id * 4 + j, i, true);
+ }
+ }
+
+ bucket_id = GetNextBucket(max_hash, max_bucket, old_extra_table, &bucket);
+ if (!bucket_id)
+ break;
+ }
+ }
+}
+
+void IndexTable::MoveSingleCell(IndexCell* current_cell, int cell_id,
+ int main_table_index, bool growing) {
+ uint32 hash = (EntryCell::GetHash(*current_cell) << 14) | main_table_index;
+ EntryCell old_cell(cell_id, hash, *current_cell);
+
+ EntryCell new_cell = CreateEntryCell(hash, old_cell.GetAddress());
+ if (!new_cell.IsValid())
+ return; // We'll deal with this entry later.
+
+ new_cell.set_state(old_cell.state());
+ new_cell.set_group(old_cell.group());
+ new_cell.set_reuse(old_cell.reuse());
+ new_cell.set_timestamp(old_cell.GetTimestamp());
+ Save(&new_cell);
+
+ if (old_cell.state() == ENTRY_DELETED) {
+ bitmap_->Set(new_cell.cell_id(), false);
+ backup_bitmap_->Set(new_cell.cell_id(), false);
+ }
+
+ if (!growing || cell_id / 4 == main_table_index) {
+ // Only delete entries that live on the main table.
+ old_cell.Clear();
+ Write(old_cell);
+ }
+}
+
+void IndexTable::HandleMisplacedCell(IndexCell* current_cell, int cell_id,
+ int main_table_index) {
+ // The cell may be misplaced, or a duplicate cell exists with this data.
+ uint32 hash = (EntryCell::GetHash(*current_cell) << 14) | main_table_index;
+ MoveSingleCell(current_cell, cell_id, main_table_index, false);
+
+ // Now look for a duplicate cell.
+ CheckBucketList(hash & mask_);
+}
+
+void IndexTable::CheckBucketList(int bucket_id) {
+ typedef std::pair<int, EntryGroup> AddressAndGroup;
+ std::set<AddressAndGroup> entries;
+ IndexBucket* bucket = &main_table_[bucket_id];
+ for (;;) {
+ for (int i = 0; i < 4; i++) {
+ IndexCell* current_cell = &bucket->cells[i];
+ if (!current_cell->address)
+ continue;
+ if (!SanityCheck(*current_cell)) {
+ NOTREACHED();
+ current_cell->Clear();
+ continue;
+ }
+ int cell_id = bucket_id * 4 + i;
+ EntryCell cell(cell_id, 0, *current_cell);
+ if (!entries.insert(std::make_pair(cell.GetAddress().value(),
+ cell.group())).second) {
+ current_cell->Clear();
+ continue;
+ }
+ CheckState(current_cell, cell_id);
+ }
+
+ bucket_id = GetNextBucket(mask_ + 1, header()->max_bucket, extra_table_,
+ &bucket);
+ if (!bucket_id)
+ break;
+ }
+}
+
+// Things we can be doing:
+//
+// - Updating timestamps
+// Fast, but we go through a few backup cycles to make sure it sticks
+// - Growing the extra table -> increase bitmap size, remap
+// Just a matter of tripping to the cache thread. Everything keeps moving
+// - Growing the whole table -> relocating all entries, may take a while
+// - Evictions... only when we are NOT doing something else? just find the
+// entries again so that there's no invalidation of lists
+
+} // namespace disk_cache
Property changes on: net\disk_cache\v3\index_table.cc
___________________________________________________________________
Added: svn:eol-style
+ LF
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