More memory stats code cleanup:...

base/process_util_win.cc

 // Copyright (c) 2009 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/process_util.h"
 
 #include <fcntl.h>
 #include <io.h>
 #include <windows.h>
 #include <winternl.h>
@@ skipping 781 matching lines @@
   // signal() handling in process_util_posix.cc.
   g_previous_filter = SetUnhandledExceptionFilter(&StackDumpExceptionFilter);
   AttachToConsole();
   return true;
 }
 
 void RaiseProcessToHighPriority() {
   SetPriorityClass(GetCurrentProcess(), HIGH_PRIORITY_CLASS);
 }
 
+// GetPerformanceInfo is not available on WIN2K.  So we'll
+// load it on-the-fly.
+const wchar_t kPsapiDllName[] = L"psapi.dll";
+typedef BOOL (WINAPI *GetPerformanceInfoFunction) (
+    PPERFORMANCE_INFORMATION pPerformanceInformation,
+    DWORD cb);
+
+// Beware of races if called concurrently from multiple threads.
+static BOOL InternalGetPerformanceInfo(
+    PPERFORMANCE_INFORMATION pPerformanceInformation, DWORD cb) {
+  static GetPerformanceInfoFunction GetPerformanceInfo_func = NULL;
+  if (!GetPerformanceInfo_func) {
+    HMODULE psapi_dll = ::GetModuleHandle(kPsapiDllName);
+    if (psapi_dll)
+      GetPerformanceInfo_func = reinterpret_cast<GetPerformanceInfoFunction>(
+          GetProcAddress(psapi_dll, "GetPerformanceInfo"));
+
+    if (!GetPerformanceInfo_func) {
+      // The function could be loaded!
+      memset(pPerformanceInformation, 0, cb);
+      return FALSE;
+    }
+  }
+  return GetPerformanceInfo_func(pPerformanceInformation, cb);
+}
+
+size_t GetSystemCommitCharge() {
+  // Get the System Page Size.
+  SYSTEM_INFO system_info;
+  GetSystemInfo(&system_info);
+
+  PERFORMANCE_INFORMATION info;
+  if (! InternalGetPerformanceInfo(&info, sizeof(info))) {
+    LOG(ERROR) << "Failed to fetch internal performance info.";

[vandebo (ex-Chrome), 2009/11/09 19:10:29]

Error/Warning ?

+    return 0;
+  }
+  return (info.CommitTotal * system_info.dwPageSize) / 1024;
+}
+
 }  // namespace base