Add ProcessPowerCollector to audit power information.

chrome/browser/power/process_power_collector.h

Index: chrome/browser/power/process_power_collector.h
diff --git a/chrome/browser/power/process_power_collector.h b/chrome/browser/power/process_power_collector.h
new file mode 100644
index 0000000000000000000000000000000000000000..9b8181516decaa0c196a260a85c0cb9894e20f85
--- /dev/null
+++ b/chrome/browser/power/process_power_collector.h
@@ -0,0 +1,109 @@
+// Copyright 2014 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.
+
+#ifndef CHROME_BROWSER_POWER_PROCESS_POWER_COLLECTOR_H_
+#define CHROME_BROWSER_POWER_PROCESS_POWER_COLLECTOR_H_
+
+#include <map>
+
+#include "base/memory/linked_ptr.h"
+#include "base/process/process_handle.h"
+#include "base/process/process_metrics.h"
+#include "base/timer/timer.h"
+#include "components/power/origin_power_map_factory.h"
+#include "url/gurl.h"
+
+class Profile;
+
+namespace content {
+class RenderProcessHost;
+}
+
+// Manages regular updates of the profile power consumption.
+class ProcessPowerCollector {
+ public:
+  ProcessPowerCollector();
+  ~ProcessPowerCollector();
+
+  class PerProcessData {
+   public:
+    explicit PerProcessData(base::ProcessMetrics* metrics,

[Daniel Erat, 2014/08/20 00:10:42]

nit: don't need explicit here anymore; also change first argument to
scoped_ptr<base::ProcessMetrics>

[Daniel Nishi, 2014/08/20 17:16:46]

Done.

+                            const GURL& origin,
+                            Profile* profile);
+    PerProcessData();
+    ~PerProcessData();
+
+    // Accessors
+    base::ProcessMetrics* metrics() const { return metrics_.get(); }

[Daniel Erat, 2014/08/20 00:10:42]

return a pointer-to-const?

[Daniel Nishi, 2014/08/20 17:16:46]

ProcessMetrics::GetCpuUsage() isn't const, so I don't think I can do that.

+    Profile* profile() const { return profile_; }
+    GURL last_origin() const { return last_origin_; }
+    int last_cpu_used() const { return last_cpu_percent_; }

[Daniel Erat, 2014/08/20 00:10:42]

rename accessor to last_cpu_percent() to match data member

[Daniel Nishi, 2014/08/20 17:16:46]

Done.

+
+    void SetLastCpuPercent(int new_cpu);

[Daniel Erat, 2014/08/20 00:10:42]

this is a simple setter; rename it to set_last_cpu_percent() and inline it

[Daniel Nishi, 2014/08/20 17:16:46]

Done.

+
+   private:
+    // |metrics_| holds the ProcessMetrics information for the given process.
+    scoped_ptr<base::ProcessMetrics> metrics_;
+
+    // |profile| is the profile that is visiting the |last_origin_|.
+    // It is not owned by PerProcessData.
+    Profile* profile_;
+    // |last_origin_| is the last origin visited by the process.
+    GURL last_origin_;
+    // |last_cpu_percent_| is the proportion of the CPU used since the last
+    // query.
+    int last_cpu_percent_;
+
+    DISALLOW_COPY_AND_ASSIGN(PerProcessData);
+  };
+
+  // A map from all process handles to a metric.
+  typedef std::map<base::ProcessHandle, linked_ptr<PerProcessData> >
+      ProcessMetricsMap;
+
+  // Begin periodically updating the power consumption numbers by profile.
+  void StartUpdating();
+
+  ProcessMetricsMap* metrics_map_for_testing() { return &metrics_map_; }
+
+ private:
+  FRIEND_TEST_ALL_PREFIXES(BrowserProcessPowerTest, NoSite);
+  FRIEND_TEST_ALL_PREFIXES(BrowserProcessPowerTest, OneSite);
+  FRIEND_TEST_ALL_PREFIXES(BrowserProcessPowerTest, MultipleSites);
+  FRIEND_TEST_ALL_PREFIXES(BrowserProcessPowerTest,
+                           IncognitoDoesntRecordPowerUsage);
+  FRIEND_TEST_ALL_PREFIXES(BrowserProcessPowerTest,
+                           MultipleProfilesRecordSeparately);
+  FRIEND_TEST_ALL_PREFIXES(BrowserProcessPowerTest, AppsRecordPowerUsage);
+
+  // Callback from the timer to update. Invokes the update power consumption
+  // procedure.
+  void UpdatePowerConsumptionCallback();
+
+  // Updates the |metrics_map_| with currently active processes.
+  void UpdateMetricsMap();

[Daniel Erat, 2014/08/20 00:10:42]

this method name seems too vague; the next two methods also update the map.
SynchronizeProcesses()?

[Daniel Nishi, 2014/08/20 17:16:46]

Seems like a good name. Done.

+
+  // Updates the |metrics_map_| with updated CPU usage information and
+  // removes all inactive processes from the |metrics_map_|.
+  double PopulateCpuUsageByOrigin();

[Daniel Erat, 2014/08/20 00:10:42]

s/Populate/Collect/, maybe?

[Daniel Nishi, 2014/08/20 17:16:46]

Done.

+
+  // Attributes the power usage to the profiles and origins given a total amount

[Daniel Erat, 2014/08/20 00:10:42]

mention that this uses the data written to |metrics_map_| by
{Populate,Collect}CpuUsageByOrigin()

[Daniel Nishi, 2014/08/20 17:16:46]

Done.

+  // of CPU used in this cycle, |cpu_cycle|.
+  void RecordCpuUsageByOrigin(double cpu_cycle);
+
+  // Iterates over all tabs to determine the power usage since the last sweep.
+  void UpdatePowerConsumption();
+
+  // Adds the information from a given RenderProcessHost to the |metrics_map_|
+  // for a given origin.
+  void AddProcessToMap(const content::RenderProcessHost* render_process,
+                       const GURL& origin);
+
+  ProcessMetricsMap metrics_map_;
+  base::RepeatingTimer<ProcessPowerCollector> timer_;
+
+  DISALLOW_COPY_AND_ASSIGN(ProcessPowerCollector);
+};
+
+#endif  // CHROME_BROWSER_POWER_PROCESS_POWER_COLLECTOR_H_