Add process start time and CPU time columns to task manager

chrome/browser/task_manager/sampling/shared_sampler.h

 // 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.
 
 #ifndef CHROME_BROWSER_TASK_MANAGER_SAMPLING_SHARED_SAMPLER_H_
 #define CHROME_BROWSER_TASK_MANAGER_SAMPLING_SHARED_SAMPLER_H_
 
 #include <map>
 #include <memory>
 #include <utility>
@@ skipping 23 matching lines @@
 class SharedSampler : public base::RefCountedThreadSafe<SharedSampler> {
  public:
   explicit SharedSampler(
       const scoped_refptr<base::SequencedTaskRunner>& blocking_pool_runner);
 
   // Below are the types of callbacks that are invoked on the UI thread
   // when the refresh is done on the worker thread.
   // These callbacks are passed via RegisterCallbacks.
   using OnIdleWakeupsCallback = base::Callback<void(int)>;
   using OnPhysicalMemoryCallback = base::Callback<void(int64_t)>;
+  using OnStartTimeCallback = base::Callback<void(int64_t)>;
+  using OnCpuTimeCallback = base::Callback<void(int64_t)>;
 
   // Returns a combination of refresh flags supported by the shared sampler.
   int64_t GetSupportedFlags() const;
 
   // Registers task group specific callbacks.
   void RegisterCallbacks(base::ProcessId process_id,
                          const OnIdleWakeupsCallback& on_idle_wakeups,
-                         const OnPhysicalMemoryCallback& on_physical_memory);
+                         const OnPhysicalMemoryCallback& on_physical_memory,
+                         const OnStartTimeCallback& on_start_time,
+                         const OnCpuTimeCallback& on_cpu_time);
 
   // Unregisters task group specific callbacks.
   void UnregisterCallbacks(base::ProcessId process_id);
 
   // Refreshes the expensive process' stats (for now only idle wakeups per
   // second) on the worker thread.
   void Refresh(base::ProcessId process_id, int64_t refresh_flags);
 
  private:
   friend class base::RefCountedThreadSafe<SharedSampler>;
   ~SharedSampler();
 
 #if defined(OS_WIN)
   // The UI-thread callbacks in TaskGroup registered with RegisterCallbacks and
   // to be called when refresh on the worker thread is done.
   struct Callbacks {
     Callbacks();
     Callbacks(Callbacks&& other);
     ~Callbacks();
 
     OnIdleWakeupsCallback on_idle_wakeups;
     OnPhysicalMemoryCallback on_physical_memory;
+    OnStartTimeCallback on_start_time;
+    OnCpuTimeCallback on_cpu_time;
 
    private:
     DISALLOW_COPY_AND_ASSIGN(Callbacks);
   };
 
   typedef std::map<base::ProcessId, Callbacks> CallbacksMap;
 
   // Contains all results of refresh for a single process.
   struct RefreshResult {
     base::ProcessId process_id;
     int idle_wakeups_per_second;
     int64_t physical_bytes;
+    int64_t start_time;

[brucedawson, 2016/12/19 21:51:05]

Should these be using a type that includes semantic information about units?
It's not clear what the units of start_time or cpu_time are. Right now these
need a comment, but using an appropriate type could avoid that.

It looks like these are using the wacky Windows 100 ns units, which is fine, but
does require a comment. Also should consider using uint64_t to avoid casts -
it's equivalent to ULONGLONG.

[chengx, 2016/12/20 00:51:12]

Done.

+    int64_t cpu_time;
   };
 
   typedef std::vector<RefreshResult> RefreshResults;
 
   // Posted on the worker thread to do the actual refresh.
   std::unique_ptr<RefreshResults> RefreshOnWorkerThread();
 
   // Called on UI thread when the refresh is done.
   void OnRefreshDone(std::unique_ptr<RefreshResults> refresh_results);
 
@@ skipping 43 matching lines @@
   // To assert we're running on the correct thread.
   base::SequenceChecker worker_pool_sequenced_checker_;
 #endif  // defined(OS_WIN)
 
   DISALLOW_COPY_AND_ASSIGN(SharedSampler);
 };
 
 }  // namespace task_manager
 
 #endif  // CHROME_BROWSER_TASK_MANAGER_SAMPLING_SHARED_SAMPLER_H_