[KVM-AUTOTEST PATCH 09/14] KVM test: remove reference to _screendump_thread at postprocessing

[Michael Goldish <mgoldish@redhat.com>]

_screendump_thread contains a reference to 'env' which prevents VMs from being
garbage collected.  This makes a difference for multi-iteration tests where
several tests run consecutively in the same process.  Removing the reference
to _screendump_thread also removes a reference to VMs, thus allowing them to be
garbage collected.  This is mainly important for the new monitor classes.

Signed-off-by: Michael Goldish <mgoldish@redhat.com>
---
 client/tests/kvm/kvm_preprocessing.py |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/client/tests/kvm/kvm_preprocessing.py b/client/tests/kvm/kvm_preprocessing.py
index 318bf3f..76c8268 100644
--- a/client/tests/kvm/kvm_preprocessing.py
+++ b/client/tests/kvm/kvm_preprocessing.py
@@ -285,6 +285,8 @@ def postprocess(test, params, env):
         logging.debug("Terminating screendump thread...")
         _screendump_thread_termination_event.set()
         _screendump_thread.join(10)
+        _screendump_thread = None
+        _screendump_thread_termination_event = None
 
     # Warn about corrupt PPM files
     for f in glob.glob(os.path.join(test.debugdir, "*.ppm")):
-- 
1.5.4.1