feat(sim/compute): Add support for resetting machine context

This change updates the interface of `SimMachineContext` to allow
workloads to reset all resources provided by the machine to the
workload. This allows us to implement a `SimWorkload` that can compose
multiple workloads.

2 files changed, 28 insertions, 18 deletions

diff --git a/opendc-simulator/opendc-simulator-compute/src/main/java/org/opendc/simulator/compute/SimAbstractMachine.java b/opendc-simulator/opendc-simulator-compute/src/main/java/org/opendc/simulator/compute/SimAbstractMachine.java
index d90a7d6f..d968d884 100644
--- a/opendc-simulator/opendc-simulator-compute/src/main/java/org/opendc/simulator/compute/SimAbstractMachine.java
+++ b/opendc-simulator/opendc-simulator-compute/src/main/java/org/opendc/simulator/compute/SimAbstractMachine.java
@@ -135,6 +135,28 @@ public abstract class SimAbstractMachine implements SimMachine {
         }
 
         @Override
+        public void reset() {
+            final FlowGraph graph = getMemory().getInput().getGraph();
+
+            for (SimProcessingUnit cpu : getCpus()) {
+                final Inlet inlet = cpu.getInput();
+                graph.disconnect(inlet);
+            }
+
+            graph.disconnect(getMemory().getInput());
+
+            for (SimNetworkInterface ifx : getNetworkInterfaces()) {
+                ((NetworkAdapter) ifx).disconnect();
+            }
+
+            for (SimStorageInterface storage : getStorageInterfaces()) {
+                StorageDevice impl = (StorageDevice) storage;
+                graph.disconnect(impl.getRead());
+                graph.disconnect(impl.getWrite());
+            }
+        }
+
+        @Override
         public final void shutdown() {
             if (isClosed) {
                 return;
@@ -180,24 +202,7 @@ public abstract class SimAbstractMachine implements SimMachine {
          * Run the stop procedures for the resources associated with the machine.
          */
         protected void doCancel() {
-            final FlowGraph graph = getMemory().getInput().getGraph();
-
-            for (SimProcessingUnit cpu : getCpus()) {
-                final Inlet inlet = cpu.getInput();
-                graph.disconnect(inlet);
-            }
-
-            graph.disconnect(getMemory().getInput());
-
-            for (SimNetworkInterface ifx : getNetworkInterfaces()) {
-                ((NetworkAdapter) ifx).disconnect();
-            }
-
-            for (SimStorageInterface storage : getStorageInterfaces()) {
-                StorageDevice impl = (StorageDevice) storage;
-                graph.disconnect(impl.getRead());
-                graph.disconnect(impl.getWrite());
-            }
+            reset();
         }
 
         @Override
diff --git a/opendc-simulator/opendc-simulator-compute/src/main/java/org/opendc/simulator/compute/SimMachineContext.java b/opendc-simulator/opendc-simulator-compute/src/main/java/org/opendc/simulator/compute/SimMachineContext.java
index f6a3bd38..5d08e2b7 100644
--- a/opendc-simulator/opendc-simulator-compute/src/main/java/org/opendc/simulator/compute/SimMachineContext.java
+++ b/opendc-simulator/opendc-simulator-compute/src/main/java/org/opendc/simulator/compute/SimMachineContext.java
@@ -68,6 +68,11 @@ public interface SimMachineContext {
     List<? extends SimStorageInterface> getStorageInterfaces();
 
     /**
+     * Reset all resources of the machine.
+     */
+    void reset();
+
+    /**
      * Shutdown the workload.
      */
     void shutdown();