Merge pull request #8 from davilaerte/fix_exit_event

Fixed issues in process scheduler event

lab_scheduling_policies/sched_simulator.py

@@ -44,7 +44,7 @@ def __init__(self):
         def take_cpu(self):
             taken = self.running_proc
             if taken:
-                assert taken.get_state() == Process.RUNNING
+                assert taken.get_state() == Process.RUNNING 
                 taken.set_state(Process.RUNNABLE)
             self.running_proc = None
             return taken
@@ -74,6 +74,7 @@ def process_is_done(proc):
 
         previous_t = Clock.current_time
         Clock.current_time = event.get_timestamp()
+        schedule_timestamp = Clock.now() + SLICE_DURATION
 
         if (event.get_type() == event_types.SCHEDULE):
 
@@ -88,14 +89,21 @@ def process_is_done(proc):
 
             #choose the next proc to enter cpu
             in_proc = scheduler.schedule(out_pid, Clock.now() - previous_t)
-
+            
             #enter cpu and schedule an exit event, if necessary
             if (in_proc):
                 cpu.enter_cpu(in_proc)
                 remaining_t = in_proc.get_service_t() - in_proc.get_usage_t()
-                if (remaining_t < SLICE_DURATION and remaining_t > 0):
-                    exit_timestamp = Clock.now() + remaining_t
-                    event_stream.add(Event(event_types.EXIT_PROC, exit_timestamp, in_proc))
+                if (remaining_t < SLICE_DURATION and remaining_t >= 0):
+					exit_timestamp = Clock.now() + remaining_t
+					if (remaining_t == 0):
+						exit_timestamp += 1
+					event_stream.add(Event(event_types.EXIT_PROC, exit_timestamp, in_proc))
+                else:
+					event_stream.add(Event(event_types.SCHEDULE, schedule_timestamp, None))
+            elif (p_table.size() > 0):
+				event_stream.add(Event(event_types.SCHEDULE, schedule_timestamp, None))
+
 
         elif (event.get_type() == event_types.ALLOC_PROC):
 
@@ -107,6 +115,9 @@ def process_is_done(proc):
             p_table.add(new_proc)
             scheduler.alloc_proc(new_proc, Clock.now() - previous_t)
             procs.append(new_proc)
+
+            if (p_table.size() == 1):
+				event_stream.add(Event(event_types.SCHEDULE, schedule_timestamp, None))				
 
         elif (event.get_type() == event_types.EXIT_PROC):
 
@@ -130,11 +141,6 @@ def process_is_done(proc):
             #force a new proc to enter the cpu
             event_stream.add(Event(event_types.SCHEDULE, Clock.now() + 1, None))
 
-        #we were not done yet, then add a new SCHEDULE event
-        if (p_table.size() > 0):
-            schedule_timestamp = Clock.now() + SLICE_DURATION
-            event_stream.add(Event(event_types.SCHEDULE, schedule_timestamp, None))
-
     return procs
 
 def enum(**enums):