Add process start time and CPU time columns to task manager

chrome/browser/task_manager/sampling/task_manager_impl.cc

 // Copyright 2015 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 "chrome/browser/task_manager/sampling/task_manager_impl.h"
 
 #include <algorithm>
 #include <string>
 #include <unordered_map>
 #include <unordered_set>
 #include <vector>
 
+#include "base/bit_cast.h"
 #include "base/command_line.h"
 #include "base/containers/adapters.h"
 #include "build/build_config.h"
 #include "chrome/browser/task_manager/providers/browser_process_task_provider.h"
 #include "chrome/browser/task_manager/providers/child_process_task_provider.h"
 #include "chrome/browser/task_manager/providers/web_contents/web_contents_task_provider.h"
 #include "chrome/browser/task_manager/sampling/shared_sampler.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/gpu_data_manager.h"
 #include "content/public/browser/render_frame_host.h"
@@ skipping 63 matching lines @@
 }
 
 void TaskManagerImpl::KillTask(TaskId task_id) {
   GetTaskByTaskId(task_id)->Kill();
 }
 
 double TaskManagerImpl::GetCpuUsage(TaskId task_id) const {
   return GetTaskGroupByTaskId(task_id)->cpu_usage();
 }
 
+base::Time TaskManagerImpl::GetStartTime(TaskId task_id) const {
+#if defined(OS_WIN)
+  uint64_t time_in_100ns = GetTaskGroupByTaskId(task_id)->start_time();
+  if (time_in_100ns == 0)
+    return base::Time();
+  FILETIME ft = bit_cast<FILETIME, int64_t>(time_in_100ns);
+  return base::Time::FromFileTime(ft);

[afakhry, 2016/12/22 00:28:14]

I'm wondering why we don't do this calculation in the shared_sampler and make it
return the ready-made base::Time and base::TimeDelta values for both the start
and CPU times respectively to the TaskGroup.

Let's keep internal things internal. How about that?

[chengx, 2016/12/22 21:42:55]

Thanks for the suggestion! I have moved the ticks-Time and ticks-TimeDelta
conversions into shared_sampler_win.cc.

+#else
+  return base::Time();
+#endif
+}
+
+base::TimeDelta TaskManagerImpl::GetCpuTime(TaskId task_id) const {
+#if defined(OS_WIN)
+  uint64_t time_in_100ns = GetTaskGroupByTaskId(task_id)->cpu_time();
+  if (time_in_100ns == 0)
+    return base::TimeDelta();
+  return base::TimeDelta::FromMicroseconds(time_in_100ns / 10);
+#else
+  return base::TimeDelta();
+#endif
+}
+
 int64_t TaskManagerImpl::GetPhysicalMemoryUsage(TaskId task_id) const {
   return GetTaskGroupByTaskId(task_id)->physical_bytes();
 }
 
 int64_t TaskManagerImpl::GetPrivateMemoryUsage(TaskId task_id) const {
   return GetTaskGroupByTaskId(task_id)->private_bytes();
 }
 
 int64_t TaskManagerImpl::GetSharedMemoryUsage(TaskId task_id) const {
   return GetTaskGroupByTaskId(task_id)->shared_bytes();
@@ skipping 434 matching lines @@
         groups_itr.second->AreBackgroundCalculationsDone();
   }
   if (are_all_processes_data_ready) {
     NotifyObserversOnRefreshWithBackgroundCalculations(GetTaskIdsList());
     for (const auto& groups_itr : task_groups_by_proc_id_)
       groups_itr.second->ClearCurrentBackgroundCalculationsFlags();
   }
 }
 
 }  // namespace task_manager