diff --git a/src/python/oftest/ofutils.py b/src/python/oftest/ofutils.py
index 5daba2f..9e59c5d 100644
--- a/src/python/oftest/ofutils.py
+++ b/src/python/oftest/ofutils.py
@@ -4,6 +4,26 @@
 """
 
 import random
+import time
 
 def gen_xid():
     return random.randrange(1,0xffffffff)
+
+"""
+Wait on a condition variable until the given function returns non-None or a timeout expires.
+The condition variable must already be acquired.
+There is deliberately no support for an infinite timeout.
+TODO: get the default timeout from configuration
+"""
+def timed_wait(cv, fn, timeout=10):
+    end_time = time.time() + timeout
+    while True:
+        if time.time() > end_time:
+            return None
+
+        val = fn()
+        if val != None:
+            return val
+
+        remaining_time = end_time - time.time()
+        cv.wait(remaining_time)