python: qemu: add timer parameter for qmp.accept socket

Also add a new _qmp_timer field to the QEMUMachine class.

Let's change the default socket timeout to None, so that if
a subclass needs to add a timer, it can be done by modifying
this private field.

At the same time, restore the timer to be 15 seconds in iotests.py, to
give an upper bound to the QMP monitor test command execution.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Acked-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20210809090114.64834-2-eesposit@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>

python/qemu/machine/machine.py

@@ -97,7 +97,8 @@ def __init__(self,
                  sock_dir: Optional[str] = None,
                  drain_console: bool = False,
                  console_log: Optional[str] = None,
-                 log_dir: Optional[str] = None):
+                 log_dir: Optional[str] = None,
+                 qmp_timer: Optional[float] = None):
         '''
         Initialize a QEMUMachine
 
@@ -112,6 +113,7 @@ def __init__(self,
         @param drain_console: (optional) True to drain console socket to buffer
         @param console_log: (optional) path to console log file
         @param log_dir: where to create and keep log files
+        @param qmp_timer: (optional) default QMP socket timeout
         @note: Qemu process is not started until launch() is used.
         '''
         # pylint: disable=too-many-arguments
@@ -121,6 +123,7 @@ def __init__(self,
         self._binary = binary
         self._args = list(args)
         self._wrapper = wrapper
+        self._qmp_timer = qmp_timer
 
         self._name = name or "qemu-%d" % os.getpid()
         self._base_temp_dir = base_temp_dir
@@ -343,7 +346,7 @@ def _pre_launch(self) -> None:
 
     def _post_launch(self) -> None:
         if self._qmp_connection:
-            self._qmp.accept()
+            self._qmp.accept(self._qmp_timer)
 
     def _post_shutdown(self) -> None:
         """

python/qemu/machine/qtest.py

@@ -115,7 +115,8 @@ def __init__(self,
                  name: Optional[str] = None,
                  base_temp_dir: str = "/var/tmp",
                  socket_scm_helper: Optional[str] = None,
-                 sock_dir: Optional[str] = None):
+                 sock_dir: Optional[str] = None,
+                 qmp_timer: Optional[float] = None):
         # pylint: disable=too-many-arguments
 
         if name is None:
@@ -124,7 +125,7 @@ def __init__(self,
             sock_dir = base_temp_dir
         super().__init__(binary, args, name=name, base_temp_dir=base_temp_dir,
                          socket_scm_helper=socket_scm_helper,
-                         sock_dir=sock_dir)
+                         sock_dir=sock_dir, qmp_timer=qmp_timer)
         self._qtest: Optional[QEMUQtestProtocol] = None
         self._qtest_path = os.path.join(sock_dir, name + "-qtest.sock")
 

tests/qemu-iotests/iotests.py

@@ -570,10 +570,11 @@ class VM(qtest.QEMUQtestMachine):
 
     def __init__(self, path_suffix=''):
         name = "qemu%s-%d" % (path_suffix, os.getpid())
+        timer = 15.0
         super().__init__(qemu_prog, qemu_opts, name=name,
                          base_temp_dir=test_dir,
                          socket_scm_helper=socket_scm_helper,
-                         sock_dir=sock_dir)
+                         sock_dir=sock_dir, qmp_timer=timer)
         self._num_drives = 0
 
     def add_object(self, opts):