neonvm-controller: add spec.cpuArchitecture field

Add spec.cpuArchitecture to use for scheduling
pods instead of relying on spec.affinity.
Add new field to the kubectl output.

neonvm/apis/neonvm/v1/virtualmachine_types.go

@@ -107,6 +107,10 @@ type VirtualMachineSpec struct {
 
 	ImagePullSecrets []corev1.LocalObjectReference `json:"imagePullSecrets,omitempty"`
 
+	// +kubebuilder:default:=amd64
+	// +optional
+	TargetArchitecture *CPUArchitecture `json:"targetArchitecture,omitempty"`
+
 	Guest Guest `json:"guest"`
 
 	// Running init containers is costly, so InitScript field should be preferred over ExtraInitContainers
@@ -170,6 +174,14 @@ func (spec *VirtualMachineSpec) Resources() VirtualMachineResources {
 	}
 }
 
+// +kubebuilder:validation:Enum=amd64;arm64
+type CPUArchitecture string
+
+const (
+	CPUArchitectureAMD64 CPUArchitecture = "amd64"
+	CPUArchitectureARM64 CPUArchitecture = "arm64"
+)
+
 // +kubebuilder:validation:Enum=QmpScaling;SysfsScaling
 type CpuScalingMode string
 
@@ -639,6 +651,7 @@ func (p VmPhase) IsAlive() bool {
 // +kubebuilder:printcolumn:name="Node",type=string,priority=1,JSONPath=`.status.node`
 // +kubebuilder:printcolumn:name="Image",type=string,priority=1,JSONPath=`.spec.guest.rootDisk.image`
 // +kubebuilder:printcolumn:name="CPUScalingMode",type=string,priority=1,JSONPath=`.spec.cpuScalingMode`
+// +kubebuilder:printcolumn:name="TargetArchitecture",type=string,priority=1,JSONPath=`.spec.targetArchitecture`
 type VirtualMachine struct {
 	metav1.TypeMeta   `json:",inline"`
 	metav1.ObjectMeta `json:"metadata,omitempty"`

neonvm/apis/neonvm/v1/virtualmachine_webhook.go

@@ -148,11 +148,25 @@ func (r *VirtualMachine) ValidateUpdate(old runtime.Object) (admission.Warnings,
 		}
 	}
 
-	// allow to change CPU scaling mode only if it's not set
-	if before.Spec.CpuScalingMode != nil && (r.Spec.CpuScalingMode == nil || *r.Spec.CpuScalingMode != *before.Spec.CpuScalingMode) {
-		return nil, fmt.Errorf(".spec.cpuScalingMode is not allowed to be changed once it's set")
+	fieldsAllowedToChangeFromNullOnly := []struct {
+		fieldName string
+		getter    func(*VirtualMachine) any
+	}{
+		{".spec.cpuScalingMode", func(v *VirtualMachine) any { return v.Spec.CpuScalingMode }},
+		{".spec.targetArchitecture", func(v *VirtualMachine) any { return v.Spec.TargetArchitecture }},
 	}
 
+	for _, info := range fieldsAllowedToChangeFromNullOnly {
+		if info.getter(before) != nil && (info.getter(r) == nil || info.getter(r) != info.getter(before)) {
+			return nil, fmt.Errorf("%s is is not allowed to be changed once it's set", info.fieldName)
+		}
+	}
+
+	// allow to change CPU scaling mode only if it's not set
+	// if before.Spec.CpuScalingMode != nil && (r.Spec.CpuScalingMode == nil || *r.Spec.CpuScalingMode != *before.Spec.CpuScalingMode) {
+	// return nil, fmt.Errorf(".spec.cpuScalingMode is not allowed to be changed once it's set")
+	// }
+
 	// validate .spec.guest.cpu.use
 	if r.Spec.Guest.CPUs.Use < r.Spec.Guest.CPUs.Min {
 		return nil, fmt.Errorf(".cpus.use (%v) should be greater than or equal to the .cpus.min (%v)",

neonvm/config/crd/bases/vm.neon.tech_virtualmachines.yaml

@@ -48,6 +48,10 @@ spec:
       name: CPUScalingMode
       priority: 1
       type: string
+    - jsonPath: .spec.targetArchitecture
+      name: TargetArchitecture
+      priority: 1
+      type: string
     name: v1
     schema:
       openAPIV3Schema:
@@ -2942,6 +2946,12 @@ spec:
                 type: boolean
               serviceAccountName:
                 type: string
+              targetArchitecture:
+                default: amd64
+                enum:
+                - amd64
+                - arm64
+                type: string
               targetRevision:
                 description: |-
                   TargetRevision is the identifier set by external party to track when changes to the spec

pkg/neonvm/controllers/vm_controller.go

@@ -27,7 +27,6 @@ import (
 	"fmt"
 	"os"
 	"reflect"
-	sysruntime "runtime"
 	"strconv"
 	"time"
 
@@ -1136,6 +1135,7 @@ func annotationsForVirtualMachine(vm *vmv1.VirtualMachine) map[string]string {
 
 func affinityForVirtualMachine(vm *vmv1.VirtualMachine) *corev1.Affinity {
 	a := vm.Spec.Affinity
+
 	if a == nil {
 		a = &corev1.Affinity{}
 	}
@@ -1145,23 +1145,29 @@ func affinityForVirtualMachine(vm *vmv1.VirtualMachine) *corev1.Affinity {
 	if a.NodeAffinity.RequiredDuringSchedulingIgnoredDuringExecution == nil {
 		a.NodeAffinity.RequiredDuringSchedulingIgnoredDuringExecution = &corev1.NodeSelector{}
 	}
-	// if NodeSelectorTerms list is empty - add default values (arch==amd64 or os==linux)
+
+	// if NodeSelectorTerms list is empty - add default values (arch==vm.Spec.Affinity or os==linux)
 	if len(a.NodeAffinity.RequiredDuringSchedulingIgnoredDuringExecution.NodeSelectorTerms) == 0 {
+		matches := []corev1.NodeSelectorRequirement{
+			{
+				Key:      "kubernetes.io/os",
+				Operator: "In",
+				Values:   []string{"linux"},
+			},
+		}
+
+		if vm.Spec.TargetArchitecture != nil {
+			matches = append(matches, corev1.NodeSelectorRequirement{
+				Key:      "kubernetes.io/arch",
+				Operator: "In",
+				Values:   []string{string(*vm.Spec.TargetArchitecture)},
+			})
+		}
+
 		a.NodeAffinity.RequiredDuringSchedulingIgnoredDuringExecution.NodeSelectorTerms = append(
 			a.NodeAffinity.RequiredDuringSchedulingIgnoredDuringExecution.NodeSelectorTerms,
 			corev1.NodeSelectorTerm{
-				MatchExpressions: []corev1.NodeSelectorRequirement{
-					{
-						Key:      "kubernetes.io/arch",
-						Operator: "In",
-						Values:   []string{sysruntime.GOARCH},
-					},
-					{
-						Key:      "kubernetes.io/os",
-						Operator: "In",
-						Values:   []string{"linux"},
-					},
-				},
+				MatchExpressions: matches,
 			})
 	}
 	return a

tests/e2e/default-values/00-assert.yaml

@@ -0,0 +1,12 @@
+apiVersion: kuttl.dev/v1beta1
+kind: TestAssert
+timeout: 10
+---
+apiVersion: vm.neon.tech/v1
+kind: VirtualMachine
+metadata:
+  name: example
+# default values for cpuScalingMode and cpuArchitecture
+spec:
+  cpuScalingMode: QmpScaling
+  targetArchitecture: amd64