[HttpCache] Store some memcache info to memory dumps for debugging

net/disk_cache/simple/simple_backend_impl.cc

 // 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/simple/simple_backend_impl.h"
 
 #include <algorithm>
 #include <cstdlib>
 #include <functional>
 #include <limits>
@@ skipping 13 matching lines @@
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/metrics/sparse_histogram.h"
 #include "base/single_thread_task_runner.h"
 #include "base/sys_info.h"
 #include "base/task_runner_util.h"
 #include "base/threading/sequenced_worker_pool.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "base/time/time.h"
 #include "base/trace_event/memory_usage_estimator.h"
+#include "base/trace_event/process_memory_dump.h"
 #include "net/base/net_errors.h"
 #include "net/disk_cache/cache_util.h"
 #include "net/disk_cache/simple/simple_entry_format.h"
 #include "net/disk_cache/simple/simple_entry_impl.h"
 #include "net/disk_cache/simple/simple_experiment.h"
 #include "net/disk_cache/simple/simple_histogram_macros.h"
 #include "net/disk_cache/simple/simple_index.h"
 #include "net/disk_cache/simple/simple_index_file.h"
 #include "net/disk_cache/simple/simple_synchronous_entry.h"
 #include "net/disk_cache/simple/simple_util.h"
@@ skipping 509 matching lines @@
   std::pair<std::string, std::string> item;
   item.first = "Cache type";
   item.second = "Simple Cache";
   stats->push_back(item);
 }
 
 void SimpleBackendImpl::OnExternalCacheHit(const std::string& key) {
   index_->UseIfExists(simple_util::GetEntryHashKey(key));
 }
 
-size_t SimpleBackendImpl::EstimateMemoryUsage() const {
+size_t SimpleBackendImpl::DumpMemoryStats(
+    base::trace_event::ProcessMemoryDump* pmd,
+    const std::string& parent_absolute_name) const {
+  base::trace_event::MemoryAllocatorDump* dump =
+      pmd->CreateAllocatorDump(parent_absolute_name + "/simple_backend");
+
+  size_t size = base::trace_event::EstimateMemoryUsage(index_) +
+                base::trace_event::EstimateMemoryUsage(active_entries_);
   // TODO(xunjieli): crbug.com/669108. Track |entries_pending_doom_| once
   // base::Closure is suppported in memory_usage_estimator.h.
-  return base::trace_event::EstimateMemoryUsage(index_) +
-         base::trace_event::EstimateMemoryUsage(active_entries_);
+  dump->AddScalar(base::trace_event::MemoryAllocatorDump::kNameSize,
+                  base::trace_event::MemoryAllocatorDump::kUnitsBytes, size);
+  return size;
 }
 
 void SimpleBackendImpl::InitializeIndex(const CompletionCallback& callback,
                                         const DiskStatResult& result) {
   if (result.net_error == net::OK) {
     index_->SetMaxSize(result.max_size);
     index_->Initialize(result.cache_dir_mtime);
   }
   callback.Run(result.net_error);
 }
@@ skipping 184 matching lines @@
 }
 
 // static
 void SimpleBackendImpl::FlushWorkerPoolForTesting() {
   // We only need to do this if we there is an active task runner.
   if (base::ThreadTaskRunnerHandle::IsSet())
     g_sequenced_worker_pool.Get().FlushForTesting();
 }
 
 }  // namespace disk_cache