Capture timing information for failed atomic actions

If an atomic action throws an exception, it will still capture timing
information; the choice of whether or not to display that information
can be left to reports. Also adds unit tests to ensure this behavior.

Change-Id: I12e96b8ac6c40904f46022a6633714d5c9b1dea1

rally/task/atomic.py

@@ -67,8 +67,7 @@ class ActionTimer(utils.Timer):
 
     def __exit__(self, type_, value, tb):
         super(ActionTimer, self).__exit__(type_, value, tb)
-        if type_ is None:
-            self.instance._atomic_actions[self.name] = self.duration()
+        self.instance._atomic_actions[self.name] = self.duration()
 
 
 def action_timer(name):

tests/unit/task/test_atomic.py

@@ -42,6 +42,23 @@ class AtomicActionTestCase(test.TestCase):
         self.assertEqual(costilius.OrderedDict(expected),
                          inst.atomic_actions())
 
+    @mock.patch("time.time", side_effect=[1, 3])
+    def test_action_timer_context_with_exception(self, mock_time):
+        inst = atomic.ActionTimerMixin()
+
+        class TestException(Exception):
+            pass
+
+        try:
+            with atomic.ActionTimer(inst, "test"):
+                raise TestException("test")
+        except TestException:
+            pass
+
+        expected = [("test", 2)]
+        self.assertEqual(costilius.OrderedDict(expected),
+                         inst.atomic_actions())
+
     @mock.patch("time.time", side_effect=[1, 3])
     def test_action_timer_decorator(self, mock_time):
 
@@ -56,6 +73,23 @@ class AtomicActionTestCase(test.TestCase):
         self.assertEqual(costilius.OrderedDict({"some": 2}),
                          inst.atomic_actions())
 
+    @mock.patch("time.time", side_effect=[1, 3])
+    def test_action_timer_decorator_with_exception(self, mock_time):
+
+        class TestException(Exception):
+            pass
+
+        class TestTimer(atomic.ActionTimerMixin):
+
+            @atomic.action_timer("test")
+            def some_func(self):
+                raise TestException("test")
+
+        inst = TestTimer()
+        self.assertRaises(TestException, inst.some_func)
+        self.assertEqual(costilius.OrderedDict({"test": 2}),
+                         inst.atomic_actions())
+
     @mock.patch("time.time", side_effect=[1, 3, 1, 3])
     def test_optional_action_timer_decorator(self, mock_time):