mgr/vol: add a helpful comment in async_job.py

Signed-off-by: Rishabh Dave <[email protected]>

Author: rishabh-d-dave

src/pybind/mgr/volumes/fs/async_job.py

@@ -133,7 +133,11 @@ def __init__(self, volume_client, name_pfx, nr_concurrent_jobs):
         # lock, cv for kickstarting jobs
         self.lock = threading.Lock()
         self.cv = threading.Condition(self.lock)
+
+        # Indicates whether or not entire async job machinery is being
+        # shutdown/stopped.
         self.stopping = threading.Event()
+
         self.cancel_cv = threading.Condition(self.lock)
         self.nr_concurrent_jobs = nr_concurrent_jobs
         self.name_pfx = name_pfx