pkg/scheduler/framework/plugins/nodename/node_name.go - master - githubmirror/kubernetes

pkg/scheduler/framework/plugins/nodename/node_name.go
102 строки4 KB
Natasha Sarkar
scheduler: implement PreFilter in NodeName plugin to restrict evaluation to assigned node for deferred resize pods
20 июл 2026, 15:42
20 июл 2026, 15:42f42fe07
/*
Copyright 2019 The Kubernetes Authors.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package nodename

import (
	"context"

	v1 "k8s.io/api/core/v1"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/apimachinery/pkg/util/sets"
	fwk "k8s.io/kube-scheduler/framework"
	"k8s.io/kubernetes/pkg/scheduler/framework/plugins/feature"
	"k8s.io/kubernetes/pkg/scheduler/framework/plugins/names"
)

// NodeName is a plugin that checks if a pod spec node name matches the current node.
type NodeName struct{}

var _ fwk.PreFilterPlugin = &NodeName{}
var _ fwk.FilterPlugin = &NodeName{}
var _ fwk.EnqueueExtensions = &NodeName{}
var _ fwk.SignPlugin = &NodeName{}

const (
	// Name is the name of the plugin used in the plugin registry and configurations.
	Name = names.NodeName

	// ErrReason returned when node name doesn't match.
	ErrReason = "node(s) didn't match the requested node name"
)

// EventsToRegister returns the possible events that may make a Pod
// failed by this plugin schedulable.
func (pl *NodeName) EventsToRegister(_ context.Context) ([]fwk.ClusterEventWithHint, error) {
	return []fwk.ClusterEventWithHint{
		// We don't need the QueueingHintFn here because the scheduling of Pods will be always retried with backoff when this Event happens.
		// (the same as Queue)
		{Event: fwk.ClusterEvent{Resource: fwk.Node, ActionType: fwk.Add}},
	}, nil
}

// Name returns name of the plugin. It is used in logs, etc.
func (pl *NodeName) Name() string {
	return Name
}

// NodeName scoring and feasibility are dependent on the NodeName field.
func (pl *NodeName) SignPod(ctx context.Context, pod *v1.Pod) ([]fwk.SignFragment, *fwk.Status) {
	return []fwk.SignFragment{
		{Key: fwk.NodeNameSignerName, Value: pod.Spec.NodeName},
	}, nil
}

// PreFilter invoked at the prefilter extension point.
func (pl *NodeName) PreFilter(ctx context.Context, state fwk.CycleState, pod *v1.Pod, nodes []fwk.NodeInfo) (*fwk.PreFilterResult, *fwk.Status) {
	if pod.Spec.NodeName != "" {
		// Pod already has a target node specified in spec.nodeName (e.g. assigned pod with deferred resize or static node assignment).
		// We restrict evaluation to that node - other nodes will be considered as UnschedulableAndUnresolvable and therefore won't be a target of preemption.
		return &fwk.PreFilterResult{
			NodeNames: sets.New(pod.Spec.NodeName),
		}, nil
	}
	return nil, nil
}

// PreFilterExtensions returns prefilter extensions, which is nil for this plugin.
func (pl *NodeName) PreFilterExtensions() fwk.PreFilterExtensions {
	return nil
}

// Filter invoked at the filter extension point.
func (pl *NodeName) Filter(ctx context.Context, _ fwk.CycleState, pod *v1.Pod, nodeInfo fwk.NodeInfo) *fwk.Status {

	if !Fits(pod, nodeInfo) {
		return fwk.NewStatus(fwk.UnschedulableAndUnresolvable, ErrReason)
	}
	return nil
}

// Fits actually checks if the pod fits the node.
func Fits(pod *v1.Pod, nodeInfo fwk.NodeInfo) bool {
	return len(pod.Spec.NodeName) == 0 || pod.Spec.NodeName == nodeInfo.Node().Name
}

// New initializes a new plugin and returns it.
func New(_ context.Context, _ runtime.Object, _ fwk.Handle, _ feature.Features) (fwk.Plugin, error) {
	return &NodeName{}, nil
}