Add cpu_stats for the browser

tools/telemetry/telemetry/core/platform/proc_util.py

 # Copyright 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.
 
 from collections import defaultdict
 
 try:
   import resource  # pylint: disable=F0401
 except ImportError:
   resource = None  # Not available on all platforms
 
 
 def _ConvertKbToByte(value):
   return int(value.replace('kB','')) * 1024
 
 
 def _GetProcFileDict(contents):
   retval = {}
   for line in contents.splitlines():
     key, value = line.split(':')
     retval[key.strip()] = value.strip()
   return retval
 
 
+def _GetProcJiffies(timer_list):
+  """Parse '/proc/timer_list' output and returns the first jiffies attribute.
+
+  Multi-CPU machines will have multiple 'jiffies:' lines, all of which will be
+  essentially the same.  Return the first one."""
+  for line in timer_list.splitlines():
+    if line.startswith('jiffies:'):
+      _, value = line.split(':')
+      return value
+  return 0

[tonyg, 2013/09/06 17:42:15]

Should this raise?

[edmundyan, 2013/09/06 21:24:51]

Done.

+
+
 def GetSystemCommitCharge(meminfo_contents):
   meminfo = _GetProcFileDict(meminfo_contents)
   return (_ConvertKbToByte(meminfo['MemTotal'])
           - _ConvertKbToByte(meminfo['MemFree'])
           - _ConvertKbToByte(meminfo['Buffers'])
           - _ConvertKbToByte(meminfo['Cached']))
 
 
+def GetCpuStats(timer_list, stats, add_children=False):
+  utime = float(stats[13])
+  stime = float(stats[14])
+  cutime = float(stats[15])
+  cstime = float(stats[16])
+  total_jiffies = float(_GetProcJiffies(timer_list))
+
+  cpu_process_jiffies = utime + stime
+  if add_children:
+    cpu_process_jiffies += cutime + cstime
+
+  return {'CpuProcessTime': cpu_process_jiffies,
+          'TotalTime': total_jiffies}
+
+
 def GetMemoryStats(status_contents, stats):
   status = _GetProcFileDict(status_contents)
   if not status or not stats or 'Z' in status['State']:
     return {}
   return {'VM': int(stats[22]),
           'VMPeak': _ConvertKbToByte(status['VmPeak']),
           'WorkingSetSize': int(stats[23]) * resource.getpagesize(),
           'WorkingSetSizePeak': _ConvertKbToByte(status['VmHWM'])}
 
 
@@ skipping 13 matching lines @@
     child_dict[int(curr_ppid)].append(int(curr_pid))
   queue = [pid]
   child_ids = []
   while queue:
     parent = queue.pop()
     if parent in child_dict:
       children = child_dict[parent]
       queue.extend(children)
       child_ids.extend(children)
   return child_ids