Purge unpinned ashmem before parsing /proc/$pid/smaps.

build/android/pylib/android_commands.py

Index: build/android/pylib/android_commands.py
diff --git a/build/android/pylib/android_commands.py b/build/android/pylib/android_commands.py
index a09461d29e89cf8510efbba5b2e2fc4380fc9de3..4c2790759bfde5afa355ecd989b3c0d329ac60df 100644
--- a/build/android/pylib/android_commands.py
+++ b/build/android/pylib/android_commands.py
@@ -22,6 +22,9 @@ import time
 import cmd_helper
 import constants
 import screenshot
+
+from utils import host_path_finder
+
 try:
   from pylib import pexpect
 except:
@@ -1418,6 +1421,20 @@ class AndroidCommands(object):
     logging.warning('Could not find disk IO stats.')
     return None
 
+  def PurgeUnpinnedAshmem(self):
+    """Purges the unpinned ashmem memory for the whole system.
+
+    This can be used to make memory measurements more stable in particular.
+    """
+    host_path = host_path_finder.GetMostRecentHostPath('purge_ashmem')
+    if not host_path:
+      raise Exception('Could not find the purge_ashmem binary.')
+    device_path = os.path.join(constants.TEST_EXECUTABLE_DIR, 'purge_ashmem')
+    self.PushIfNeeded(host_path, device_path)
+    if self.RunShellCommand(device_path, log_result=True):
+      return
+    raise Exception('Error while purging ashmem.')
+
   def GetMemoryUsageForPid(self, pid):
     """Returns the memory usage for given pid.