Use TimeTicks instead of gettimeofday in ProcessMetrics.

base/process/process_metrics_mac.cc

 // Copyright (c) 2013 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/process_metrics.h"
 
 #include <mach/mach.h>
 #include <mach/mach_vm.h>
 #include <mach/shared_region.h>
 #include <sys/sysctl.h>
@@ skipping 249 matching lines @@
   TIME_VALUE_TO_TIMEVAL(&thread_info_data.user_time, &user_timeval);
   TIME_VALUE_TO_TIMEVAL(&thread_info_data.system_time, &system_timeval);
   timeradd(&user_timeval, &system_timeval, &task_timeval);
 
   // ... task info contains terminated time.
   TIME_VALUE_TO_TIMEVAL(&task_info_data.user_time, &user_timeval);
   TIME_VALUE_TO_TIMEVAL(&task_info_data.system_time, &system_timeval);
   timeradd(&user_timeval, &task_timeval, &task_timeval);
   timeradd(&system_timeval, &task_timeval, &task_timeval);
 
-  struct timeval now;
-  int retval = gettimeofday(&now, NULL);
-  if (retval)
-    return 0;
-
-  int64 time = TimeValToMicroseconds(now);
+  TimeTicks time = TimeTicks::Now();
   int64 task_time = TimeValToMicroseconds(task_timeval);
 
-  if (last_cpu_time_ == 0) {
+  if (last_system_time_ == 0) {
     // First call, just set the last values.
-    last_cpu_time_ = time;
+    last_cpu_walltime_ = time;
     last_system_time_ = task_time;
     return 0;
   }
 
   int64 system_time_delta = task_time - last_system_time_;
-  int64 time_delta = time - last_cpu_time_;
-  DCHECK_NE(0U, time_delta);
-  if (time_delta == 0)
+  int64 walltime_delta = (time - last_cpu_walltime_).InMicroseconds();
+  DCHECK_NE(0U, walltime_delta);
+  if (walltime_delta == 0)
     return 0;
 
-  last_cpu_time_ = time;
+  last_cpu_walltime_ = time;
   last_system_time_ = task_time;
 
-  return static_cast<double>(system_time_delta * 100.0) / time_delta;
+  return static_cast<double>(system_time_delta * 100.0) / walltime_delta;
 }
 
 int ProcessMetrics::GetIdleWakeupsPerSecond() {
   mach_port_t task = TaskForPid(process_);
   if (task == MACH_PORT_NULL)
     return 0;
 
   kern_return_t kr;
 
   task_power_info power_info_data;
   mach_msg_type_number_t power_info_count = TASK_POWER_INFO_COUNT;
   kr = task_info(task,
                  TASK_POWER_INFO,
                  reinterpret_cast<task_info_t>(&power_info_data),
                  &power_info_count);
   if (kr != KERN_SUCCESS) {
     // Most likely cause: |task| is a zombie, or this is on a pre-10.8 system
     // where TASK_POWER_INFO isn't supported yet.
     return 0;
   }
   uint64_t absolute_idle_wakeups = power_info_data.task_platform_idle_wakeups;
 
-  struct timeval now;
-  int retval = gettimeofday(&now, NULL);
-  if (retval)
-    return 0;
+  TimeTicks time = TimeTicks::Now();
 
-  int64 time = TimeValToMicroseconds(now);
-
-  if (last_idle_wakeups_time_ == 0) {
+  if (last_absolute_idle_wakeups_ == 0) {
     // First call, just set the last values.
-    last_idle_wakeups_time_ = time;
+    last_idle_wakeups_walltime_ = time;
     last_absolute_idle_wakeups_ = absolute_idle_wakeups;
     return 0;
   }
 
   int64 wakeups_delta = absolute_idle_wakeups - last_absolute_idle_wakeups_;
-  int64 time_delta = time - last_idle_wakeups_time_;
-  DCHECK_NE(0U, time_delta);
-  if (time_delta == 0)
+  int64 walltime_delta = (time - last_idle_wakeups_walltime_).InMicroseconds();
+  DCHECK_NE(0U, walltime_delta);
+  if (walltime_delta == 0)
     return 0;
 
-  last_idle_wakeups_time_ = time;
+  last_idle_wakeups_walltime_ = time;
   last_absolute_idle_wakeups_ = absolute_idle_wakeups;
 
   // Round to average wakeups per second.
   const int kMicrosecondsPerSecond = 1000 * 1000;
-  return (wakeups_delta * kMicrosecondsPerSecond + time_delta/2) / time_delta;
+  return (wakeups_delta * kMicrosecondsPerSecond + walltime_delta / 2) /
+         walltime_delta;
 }
 
 bool ProcessMetrics::GetIOCounters(IoCounters* io_counters) const {
   return false;
 }
 
 ProcessMetrics::ProcessMetrics(ProcessHandle process,
                                ProcessMetrics::PortProvider* port_provider)
     : process_(process),
-      last_cpu_time_(0),
       last_system_time_(0),
-      last_idle_wakeups_time_(0),
       last_absolute_idle_wakeups_(0),
       port_provider_(port_provider) {
   processor_count_ = SysInfo::NumberOfProcessors();
 }
 
 mach_port_t ProcessMetrics::TaskForPid(ProcessHandle process) const {
   mach_port_t task = MACH_PORT_NULL;
   if (port_provider_)
     task = port_provider_->TaskForPid(process_);
   if (task == MACH_PORT_NULL && process_ == getpid())
@@ skipping 18 matching lines @@
   kr = host_page_size(host, &page_size);
   if (kr) {
     DLOG(ERROR) << "Failed to fetch host page size.";
     return 0;
   }
 
   return (data.active_count * page_size) / 1024;
 }
 
 }  // namespace base