tools/stats-viewer.py: add counter filter.

Review URL: http://codereview.chromium.org/2838028

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4975 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

tools/stats-viewer.py

@@ -34,8 +34,8 @@ The stats viewer reads counters from a binary file and displays them
 in a window, re-reading and re-displaying with regular intervals.
 """
 
-
 import mmap
+import optparse
 import os
 import re
 import struct
@@ -60,13 +60,15 @@ CHROME_COUNTERS_FILE_MAGIC_NUMBER = 0x13131313
 class StatsViewer(object):
   """The main class that keeps the data used by the stats viewer."""
 
-  def __init__(self, data_name):
+  def __init__(self, data_name, name_filter):
     """Creates a new instance.
 
     Args:
       data_name: the name of the file containing the counters.
+      name_filter: The regexp filter to apply to counter names.
     """
     self.data_name = data_name
+    self.name_filter = name_filter
 
     # The handle created by mmap.mmap to the counters file.  We need
     # this to clean it up on exit.
@@ -224,6 +226,7 @@ class StatsViewer(object):
     sorted_groups.sort()
     for counter_name in sorted_groups:
       counter_objs = groups[counter_name]
+      if self.name_filter.match(counter_name):
         name = Tkinter.Label(self.root, width=50, anchor=Tkinter.W,
                              text=counter_name)
         name.grid(row=index, column=0, padx=1, pady=1)
@@ -232,6 +235,7 @@ class StatsViewer(object):
         counter = counter_objs[i]
         name = counter.Name()
         var = Tkinter.StringVar()
+        if self.name_filter.match(name):
           value = Tkinter.Label(self.root, width=15, anchor=Tkinter.W,
                                 textvariable=var)
           value.grid(row=index, column=(1 + i), padx=1, pady=1)
@@ -440,17 +444,25 @@ class ChromeCounterCollection(object):
                          self.counter_values_offset + i * self.max_threads * 4)
 
 
-def Main(data_file):
+def Main(data_file, name_filter):
   """Run the stats counter.
 
   Args:
     data_file: The counters file to monitor.
+    name_filter: The regexp filter to apply to counter names.
   """
-  StatsViewer(data_file).Run()
+  StatsViewer(data_file, name_filter).Run()
 
 
 if __name__ == "__main__":
-  if len(sys.argv) != 2:
-    print "Usage: stats-viewer.py <stats data>|<test_shell pid>"
+  parser = optparse.OptionParser("usage: %prog [--filter=re] "
+                                 "<stats data>|<test_shell pid>")
+  parser.add_option("--filter",
+                    default=".*",
+                    help=("regexp filter for counter names "
+                          "[default: %default]"))
+  (options, args) = parser.parse_args()
+  if len(args) != 1:
+    parser.print_help()
     sys.exit(1)
-  Main(sys.argv[1])
+  Main(args[0], re.compile(options.filter))