IdleWakeups tool

tools/win/IdleWakeups/power_sampler.cpp

+// Copyright 2016 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 "stdafx.h"
+
+#include "power_sampler.h"
+
+// These correspond to the funcID values returned by GetMsrFunc
+const int MSR_FUNC_FREQ = 0;
+const int MSR_FUNC_POWER = 1;
+const int MSR_FUNC_TEMP = 2;
+const int MSR_FUNC_MAX_POWER = 3; /* ????? */
+
+void PowerSampler::SampleCPUPowerState() {
+  if (!IntelEnergyLibInitialize || !GetNumMsrs || !GetMsrName || !GetMsrFunc ||
+      !GetPowerData || !ReadSample) {
+    return;
+  }
+
+  int num_MSRs = 0;
+  GetNumMsrs(&num_MSRs);
+  ReadSample();
+
+  for (int i = 0; i < num_MSRs; ++i) {
+    int func_id;
+    wchar_t MSR_name[1024];
+    GetMsrFunc(i, &func_id);
+
+    int nData;
+    double data[3] = {};
+    GetPowerData(0, i, data, &nData);
+
+    if (func_id == MSR_FUNC_POWER) {
+      // data[0] is Power (W)
+      // data[1] is Energy (J)
+      // data[2] is Energy (mWh)
+      // Round to nearest .0001 to avoid distracting excess precision.
+      GetMsrName(i, MSR_name);
+      power_[MSR_name] = round(data[0] * 10000) / 10000;
+    }
+  }
+}
+
+PowerSampler::PowerSampler() {
+// If Intel Power Gadget is installed then use it to get CPU power data.
+#if _M_X64
+  PCWSTR dllName = L"\\EnergyLib64.dll";
+#else
+  PCWSTR dllName = L"\\EnergyLib32.dll";
+#endif
+#pragma warning(disable : 4996)
+  PCWSTR powerGadgetDir = _wgetenv(L"IPG_Dir");
+  if (powerGadgetDir)
+    energy_lib_ = LoadLibrary((std::wstring(powerGadgetDir) + dllName).c_str());
+  if (energy_lib_) {
+    IntelEnergyLibInitialize = (IntelEnergyLibInitialize_t)GetProcAddress(
+        energy_lib_, "IntelEnergyLibInitialize");
+    GetNumMsrs = (GetNumMsrs_t)GetProcAddress(energy_lib_, "GetNumMsrs");
+    GetMsrName = (GetMsrName_t)GetProcAddress(energy_lib_, "GetMsrName");
+    GetMsrFunc = (GetMsrFunc_t)GetProcAddress(energy_lib_, "GetMsrFunc");
+    GetPowerData = (GetPowerData_t)GetProcAddress(energy_lib_, "GetPowerData");
+    ReadSample = (ReadSample_t)GetProcAddress(energy_lib_, "ReadSample");
+
+    if (IntelEnergyLibInitialize && ReadSample) {
+      IntelEnergyLibInitialize();
+      ReadSample();
+    }
+  }
+}
+
+PowerSampler::~PowerSampler() {
+  if (energy_lib_)
+    FreeLibrary(energy_lib_);
+}