Android: kill all adb instances before trying to restart usb.

On some bots, there are adb instances left over from previous runs.
They don't play well with restarting the usb, and devices eventually "disappear".
This tries to kill all adb instances before restarting usb.

BUG=311058
TBR=navabi@chromium.org

Review URL: https://codereview.chromium.org/39833003

git-svn-id: http://src.chromium.org/svn/trunk/src/build@231035 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

android/buildbot/bb_device_status_check.py

@@ -8,6 +8,8 @@
 import logging
 import optparse
 import os
+import psutil
+import signal
 import smtplib
 import subprocess
 import sys
@@ -241,6 +243,24 @@ def RestartUsb():
   return 0
 
 
+def KillAllAdb():
+  def GetAllAdb():
+    for p in psutil.process_iter():
+      if 'adb' in p.name or 'adb' in ' '.join(p.cmdline):
+        yield p
+
+  for sig in [signal.SIGTERM, signal.SIGQUIT, signal.SIGKILL]:
+    for p in GetAllAdb():
+      try:
+        print 'kill %d %d (%s [%s])' % (sig, p.pid, p.name,
+            ' '.join(p.cmdline))
+        p.send_signal(sig)
+      except psutil.error.NoSuchProcess:
+        pass
+  for p in GetAllAdb():
+    print 'Unable to kill %d (%s [%s])' % (p.pid, p.name, ' '.join(p.cmdline))
+
+
 def main():
   parser = optparse.OptionParser()
   parser.add_option('', '--out-dir',
@@ -257,6 +277,7 @@ def main():
     parser.error('Unknown options %s' % args)
 
   if options.restart_usb:
+    KillAllAdb()
     rc = RestartUsb()
     if rc:
       return 1