fm_agent: Wait for fastmodel subprocess to terminate when resetting o…

…r terminating it

Releasing the model via IRIS does not reliably kill the subprocess

This gives the FVP up to 3 seconds to terminate gracefully, then force kills it

Signed-off-by: Chris Swinchatt <christopher.swinchatt@arm.com>

fm_agent/fm_agent.py

@@ -16,8 +16,8 @@
 limitations under the License.
 """
 
+import atexit
 import multiprocessing
-import sys
 import os
 from subprocess import Popen
 import time
@@ -86,10 +86,12 @@ def __init__(self, model_name=None, model_config=None, logger=None, enable_gdbse
             @param model_config is the config file to the fast model
         """
 
+        atexit.register(self.__del__)
+
         self.fastmodel_name = model_name
         self.config_name    = model_config
         self.enable_gdbserver = enable_gdbserver
-        self.subprocess = None
+        self.subprocess:Popen = None
 
         #If logging not provided, use default log
         if logger:
@@ -111,9 +113,10 @@ def __init__(self, model_name=None, model_config=None, logger=None, enable_gdbse
             pass
 
     def __del__(self):
-        if isinstance(self.subprocess, Popen):
-            self.subprocess.terminate()
-            self.subprocess.wait()
+        atexit.unregister(self.__del__)
+        self.__closeConnection()
+        self.__releaseModel()
+        self.__terminateSubprocess()
 
     def setup_simulator(self, model_name, model_config):
         """ setup the simulator, this is crucial before you can start a simulator.
@@ -257,8 +260,8 @@ def reset_simulator(self):
         if self.is_simulator_alive():
             self.logger.prn_wrn("STOP and RESTART FastModel")
             self.__closeConnection()
-            self.model.release(shutdown=True)
-            time.sleep(1)
+            self.__releaseModel()
+            self.__terminateSubprocess()
 
             self.__spawn_simulator()
 
@@ -336,8 +339,6 @@ def __closeConnection(self):
             self.socket.close()
             self.logger.prn_inf("Closing terminal socket connection")
             self.socket = None
-        else:
-            self.logger.prn_inf("Terminal socket connection already closed")
 
     def __run_to_breakpoint(self):
         try:
@@ -425,12 +426,26 @@ def shutdown_simulator(self):
                 self.__CodeCoverage()
             self.logger.prn_inf("Fast-Model agent shutting down model")
             self.__closeConnection()
-            self.model.release(shutdown=True)
-            self.model=None
-            time.sleep(1)
+            self.__releaseModel()
+            self.__terminateSubprocess()
         else:
             self.logger.prn_inf("Model already shutdown")
 
+    def __releaseModel(self):
+        if self.model:
+            self.model.release(shutdown=True)
+            del self.model
+            self.model = None
+
+    def __terminateSubprocess(self):
+        if self.subprocess:
+            self.subprocess.terminate()
+            if self.subprocess.wait(3) is None:
+                self.subprocess.kill()
+                self.subprocess.wait()
+                del self.subprocess
+                self.subprocess = None
+
     def list_avaliable_models(self):
         """ return a dictionary of models and configs """
         return self.configuration.get_all_configs()