[WIP] Add SharedMemoryTracker to dump base::SharedMemory usage

base/memory/shared_memory_win.cc

 // Copyright (c) 2011 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 "base/memory/shared_memory.h"
 
 #include <aclapi.h>
 #include <stddef.h>
 #include <stdint.h>
 
 #include "base/logging.h"
+#include "base/memory/shared_memory_tracker.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/rand_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
 
 namespace {
 
 // Errors that can occur during Shared Memory construction.
 // These match tools/metrics/histograms/histograms.xml.
 // This enum is append-only.
@@ skipping 297 matching lines @@
 
   if (external_section_ && !IsSectionSafeToMap(mapped_file_.Get()))
     return false;
 
   memory_ = MapViewOfFile(
       mapped_file_.Get(),
       read_only_ ? FILE_MAP_READ : FILE_MAP_READ | FILE_MAP_WRITE,
       static_cast<uint64_t>(offset) >> 32, static_cast<DWORD>(offset), bytes);
   if (memory_ != NULL) {
     DCHECK_EQ(0U, reinterpret_cast<uintptr_t>(memory_) &
-        (SharedMemory::MAP_MINIMUM_ALIGNMENT - 1));
+                      (SharedMemory::MAP_MINIMUM_ALIGNMENT - 1));
     mapped_size_ = GetMemorySectionSize(memory_);
+    SharedMemoryTracker::GetInstance()->IncrementMemoryUsage(*this);
     return true;
   }
   return false;
 }
 
 bool SharedMemory::Unmap() {
   if (memory_ == NULL)
     return false;
 
   UnmapViewOfFile(memory_);
+  SharedMemoryTracker::GetInstance()->DecrementMemoryUsage(*this);
   memory_ = NULL;
   return true;
 }
 
 bool SharedMemory::ShareToProcessCommon(ProcessHandle process,
                                         SharedMemoryHandle* new_handle,
                                         bool close_self,
                                         ShareMode share_mode) {
   *new_handle = SharedMemoryHandle();
   DWORD access = FILE_MAP_READ | SECTION_QUERY;
@@ skipping 19 matching lines @@
                          access, FALSE, options)) {
     return false;
   }
   *new_handle = SharedMemoryHandle(result, base::GetProcId(process));
   new_handle->SetOwnershipPassesToIPC(true);
   return true;
 }
 
 
 void SharedMemory::Close() {
+  SharedMemoryTracker::GetInstance()->DecrementMemoryUsage(*this);

[Primiano Tucci (use gerrit), 2017/01/20 16:34:52]

see my prev comment about close vs unmap. I think you should just ignore close()

[hajimehoshi, 2017/01/23 11:59:09]

Done.

   mapped_file_.Close();
 }
 
 SharedMemoryHandle SharedMemory::handle() const {
   return SharedMemoryHandle(mapped_file_.Get(), base::GetCurrentProcId());
 }
 
 SharedMemoryHandle SharedMemory::TakeHandle() {
   SharedMemoryHandle handle(mapped_file_.Take(), base::GetCurrentProcId());
   handle.SetOwnershipPassesToIPC(true);
   memory_ = nullptr;
   mapped_size_ = 0;
   return handle;
 }
 
 }  // namespace base