python: Update switchable processor to support KVM

Change-Id: Ie843e2b4ab6e506bb195bfcef33cead9a6273901
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/50127
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>

components_library/processors/simple_switchable_processor.py

@@ -56,10 +56,6 @@ class SimpleSwitchableProcessor(SwitchableProcessor):
         self._start_key = "start"
         self._switch_key = "switch"
         self._current_is_start = True
-        self._prepare_kvm = CPUTypes.KVM in (
-            starting_core_type,
-            switch_core_type,
-        )
 
         if starting_core_type in (CPUTypes.TIMING, CPUTypes.O3):
             self._mem_mode = MemMode.TIMING
@@ -90,9 +86,6 @@ class SimpleSwitchableProcessor(SwitchableProcessor):
     def incorporate_processor(self, board: AbstractBoard) -> None:
         super().incorporate_processor(board=board)
 
-        if self._prepare_kvm:
-            board.kvm_vm = KvmVM()
-
         board.set_mem_mode(self._mem_mode)
 
     def switch(self):

components_library/processors/switchable_processor.py

@@ -26,6 +26,9 @@
 
 from components_library.processors.simple_core import SimpleCore
 from components_library.processors.abstract_core import AbstractCore
+
+from .cpu_types import CPUTypes
+
 import m5
 
 from typing import Dict, Any, List
@@ -65,6 +68,15 @@ class SwitchableProcessor(AbstractProcessor):
                 core.set_switched_out(core not in self._current_cores)
                 all_cores.append(core)
 
+        self._prepare_kvm = CPUTypes.KVM in [
+            core.get_type() for core in all_cores
+        ]
+
+        if self._prepare_kvm:
+            from m5.objects import KvmVM
+
+            self.kvm_vm = KvmVM()
+
         super(SwitchableProcessor, self).__init__(cores=all_cores)
 
     @overrides(AbstractProcessor)
@@ -76,6 +88,16 @@ class SwitchableProcessor(AbstractProcessor):
         # procsesor
         self._board = board
 
+        if self._prepare_kvm:
+            board.kvm_vm = self.kvm_vm
+
+            # To get the KVM CPUs to run on different host CPUs
+            # Specify a different event queue for each CPU
+            for i, core in enumerate(self.cores):
+                for obj in core.get_simobject().descendants():
+                    obj.eventq_index = 0
+                core.get_simobject().eventq_index = i + 1
+
     @overrides(AbstractProcessor)
     def get_num_cores(self) -> int:
         # Note: This is a special case where the total number of cores in the