apiextensions: only create patch reference object for smp path

staging/src/k8s.io/apiserver/pkg/endpoints/handlers/patch.go

@@ -82,12 +82,6 @@ func PatchResource(r rest.Patcher, scope RequestScope, admit admission.Interface
 		ctx := req.Context()
 		ctx = request.WithNamespace(ctx, namespace)
 
-		schemaReferenceObj, err := scope.UnsafeConvertor.ConvertToVersion(r.New(), scope.Kind.GroupVersion())
-		if err != nil {
-			scope.err(err, w, req)
-			return
-		}
-
 		patchJS, err := readBody(req)
 		if err != nil {
 			scope.err(err, w, req)
@@ -134,8 +128,6 @@ func PatchResource(r rest.Patcher, scope RequestScope, admit admission.Interface
 
 			timeout: timeout,
 
-			schemaReferenceObj: schemaReferenceObj,
-
 			restPatcher: r,
 			name:        name,
 			patchType:   patchType,
@@ -191,9 +183,6 @@ type patcher struct {
 
 	timeout time.Duration
 
-	// Schema
-	schemaReferenceObj runtime.Object
-
 	// Operation information
 	restPatcher rest.Patcher
 	name        string
@@ -263,6 +252,9 @@ func (p *jsonPatcher) applyJSPatch(versionedJS []byte) (patchedJS []byte, retErr
 
 type smpPatcher struct {
 	*patcher
+
+	// Schema
+	schemaReferenceObj runtime.Object
 }
 
 func (p *smpPatcher) applyPatchToCurrentObject(currentObject runtime.Object) (runtime.Object, error) {
@@ -352,7 +344,11 @@ func (p *patcher) patchResource(ctx context.Context) (runtime.Object, error) {
 	case types.JSONPatchType, types.MergePatchType:
 		p.mechanism = &jsonPatcher{patcher: p}
 	case types.StrategicMergePatchType:
-		p.mechanism = &smpPatcher{patcher: p}
+		schemaReferenceObj, err := p.unsafeConvertor.ConvertToVersion(p.restPatcher.New(), p.kind.GroupVersion())
+		if err != nil {
+			return nil, err
+		}
+		p.mechanism = &smpPatcher{patcher: p, schemaReferenceObj: schemaReferenceObj}
 	default:
 		return nil, fmt.Errorf("%v: unimplemented patch type", p.patchType)
 	}

staging/src/k8s.io/apiserver/pkg/endpoints/handlers/rest_test.go

@@ -394,8 +394,6 @@ func (tc *patchTestCase) Run(t *testing.T) {
 
 			timeout: 1 * time.Second,
 
-			schemaReferenceObj: schemaReferenceObj,
-
 			restPatcher: testPatcher,
 			name:        name,
 			patchType:   patchType,