File 0010-threadPool-Do-not-keep-reference-to-tasks.patch of Package vdsm

File 0010-threadPool-Do-not-keep-reference-to-tasks.patch of Package vdsm (Revision b8a0370be37a497fe883af63aa06d311)

Currently displaying revision b8a0370be37a497fe883af63aa06d311, show latest

From 9b2d7c22e806ead1c499b1da304bff6da21a5f67 Mon Sep 17 00:00:00 2001
From: Nir Soffer <nsoffer@redhat.com>
Date: Sun, 8 Dec 2013 00:49:36 +0200
Subject: [PATCH 10/11] threadPool: Do not keep reference to tasks

Worker thread was taking a task from the threadpool queue, run it, and
then hold it until the next task is run. This causes the task and all
objects referenced from it to keep living until the next task is run by
this thread.

This patch ensure that worker thread does not keep referece to tasks
after they were run.

Change-Id: Ib6e024e0727e11a4c98f4e5ede20229d148fdc58
Relates-To: https://bugzilla.redhat.com/1032925
Signed-off-by: Nir Soffer <nsoffer@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/22136
Reviewed-by: Ayal Baron <abaron@redhat.com>
Reviewed-by: Allon Mureinik <amureini@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/22208
Reviewed-by: Yaniv Bronhaim <ybronhei@redhat.com>
Tested-by: Yaniv Bronhaim <ybronhei@redhat.com>
---
 vdsm/storage/threadPool.py | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/vdsm/storage/threadPool.py b/vdsm/storage/threadPool.py
index b1f3142..a0e24a2 100644
--- a/vdsm/storage/threadPool.py
+++ b/vdsm/storage/threadPool.py
@@ -191,8 +191,8 @@ class WorkerThread(threading.Thread):
         it, calling the callback if any.  """
 
         while not self.__isDying:
+            id, cmd, args, callback = self.__pool.getNextTask()
             try:
-                id, cmd, args, callback = self.__pool.getNextTask()
                 if id is None:  # should retry.
                     pass
                 elif self.__isDying:
@@ -212,6 +212,11 @@ class WorkerThread(threading.Thread):
                     self.__pool.setRunningTask(False)
             except Exception:
                 self.log.error("Task %s failed" % repr(cmd), exc_info=True)
+            finally:
+                # Don't keep reference to objects taken from the pool.
+                # Otherwise this thread may keep those object alive until the
+                # next iteration. See BZ#1032925.
+                del id, cmd, args, callback
 
     def goAway(self):
 
-- 
1.8.4.2