correctly handle term signals

- adhoc now terminates gracefully
- avoid race condition on terminations by ignoring errors if
  worker might have been reaped between checking if active and termination call
- ansible-playbook now properly exits on sigint/term
- adhoc and playbook now give exceptions that we should not normally capture
  and rely on top level finally to reap children
- handle systemexit breaks in workers
- added debug to see at which frame we exit
partial fix for #14346

lib/ansible/executor/process/result.py

@@ -163,7 +163,7 @@ class ResultProcess(multiprocessing.Process):
 
             except queue.Empty:
                 pass
-            except (KeyboardInterrupt, IOError, EOFError):
+            except (KeyboardInterrupt, SystemExit, IOError, EOFError):
                 break
             except:
                 # TODO: we should probably send a proper callback here instead of

lib/ansible/executor/process/worker.py

@@ -132,7 +132,7 @@ class WorkerProcess(multiprocessing.Process):
             self._rslt_q.put(task_result, block=False)
 
         except Exception as e:
-            if not isinstance(e, (IOError, EOFError, KeyboardInterrupt)) or isinstance(e, TemplateNotFound):
+            if not isinstance(e, (IOError, EOFError, KeyboardInterrupt, SystemExit)) or isinstance(e, TemplateNotFound):
                 try:
                     self._host.vars = dict()
                     self._host.groups = []
@@ -140,7 +140,7 @@ class WorkerProcess(multiprocessing.Process):
                     self._rslt_q.put(task_result, block=False)
                 except:
                     debug(u"WORKER EXCEPTION: %s" % to_unicode(e))
-                    debug(u"WORKER EXCEPTION: %s" % to_unicode(traceback.format_exc()))
+                    debug(u"WORKER TRACEBACK: %s" % to_unicode(traceback.format_exc()))
 
         debug("WORKER PROCESS EXITING")