scheduler: central ResourceClaim assume cache

This enables connecting the event handler for ResourceClaim to the assume
cache, which addresses a theoretic race condition.

It may also be useful for implementing the autoscaler support, because now
the autoscaler can modify the content of the cache.

pkg/scheduler/eventhandlers.go

@@ -43,6 +43,7 @@ import (
 	"k8s.io/kubernetes/pkg/scheduler/framework/plugins/noderesources"
 	"k8s.io/kubernetes/pkg/scheduler/internal/queue"
 	"k8s.io/kubernetes/pkg/scheduler/profile"
+	"k8s.io/kubernetes/pkg/scheduler/util/assumecache"
 )
 
 func (sched *Scheduler) onStorageClassAdd(obj interface{}) {
@@ -288,6 +289,7 @@ func addAllEventHandlers(
 	sched *Scheduler,
 	informerFactory informers.SharedInformerFactory,
 	dynInformerFactory dynamicinformer.DynamicSharedInformerFactory,
+	resourceClaimCache *assumecache.AssumeCache,
 	gvkMap map[framework.GVK]framework.ActionType,
 ) error {
 	var (
@@ -456,12 +458,11 @@ func addAllEventHandlers(
 			}
 		case framework.ResourceClaim:
 			if utilfeature.DefaultFeatureGate.Enabled(features.DynamicResourceAllocation) {
-				if handlerRegistration, err = informerFactory.Resource().V1alpha2().ResourceClaims().Informer().AddEventHandler(
-					buildEvtResHandler(at, framework.ResourceClaim, "ResourceClaim"),
-				); err != nil {
-					return err
-				}
-				handlers = append(handlers, handlerRegistration)
+				// No need to wait for this cache to be
+				// populated. If a claim is not yet in the
+				// cache, scheduling will get retried once it
+				// is.
+				resourceClaimCache.AddEventHandler(buildEvtResHandler(at, framework.ResourceClaim, "ResourceClaim"))
 			}
 		case framework.ResourceClass:
 			if utilfeature.DefaultFeatureGate.Enabled(features.DynamicResourceAllocation) {

pkg/scheduler/eventhandlers_test.go

@@ -29,6 +29,7 @@ import (
 	storagev1 "k8s.io/api/storage/v1"
 	"k8s.io/apimachinery/pkg/api/resource"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	"k8s.io/klog/v2/ktesting"
 
 	"k8s.io/apimachinery/pkg/runtime"
@@ -38,6 +39,7 @@ import (
 	"k8s.io/client-go/informers"
 	"k8s.io/client-go/kubernetes/fake"
 
+	"k8s.io/kubernetes/pkg/features"
 	"k8s.io/kubernetes/pkg/scheduler/framework"
 	"k8s.io/kubernetes/pkg/scheduler/framework/plugins/nodeaffinity"
 	"k8s.io/kubernetes/pkg/scheduler/framework/plugins/nodename"
@@ -46,6 +48,7 @@ import (
 	"k8s.io/kubernetes/pkg/scheduler/internal/cache"
 	"k8s.io/kubernetes/pkg/scheduler/internal/queue"
 	st "k8s.io/kubernetes/pkg/scheduler/testing"
+	"k8s.io/kubernetes/pkg/scheduler/util/assumecache"
 )
 
 func TestNodeAllocatableChanged(t *testing.T) {
@@ -447,8 +450,13 @@ func TestAddAllEventHandlers(t *testing.T) {
 
 			dynclient := dyfake.NewSimpleDynamicClient(scheme)
 			dynInformerFactory := dynamicinformer.NewDynamicSharedInformerFactory(dynclient, 0)
+			var resourceClaimCache *assumecache.AssumeCache
+			if utilfeature.DefaultFeatureGate.Enabled(features.DynamicResourceAllocation) {
+				resourceClaimInformer := informerFactory.Resource().V1alpha2().ResourceClaims().Informer()
+				resourceClaimCache = assumecache.NewAssumeCache(logger, resourceClaimInformer, "ResourceClaim", "", nil)
+			}
 
-			if err := addAllEventHandlers(&testSched, informerFactory, dynInformerFactory, tt.gvkMap); err != nil {
+			if err := addAllEventHandlers(&testSched, informerFactory, dynInformerFactory, resourceClaimCache, tt.gvkMap); err != nil {
 				t.Fatalf("Add event handlers failed, error = %v", err)
 			}
 

pkg/scheduler/framework/interface.go

@@ -38,6 +38,7 @@ import (
 	"k8s.io/klog/v2"
 	"k8s.io/kubernetes/pkg/scheduler/apis/config"
 	"k8s.io/kubernetes/pkg/scheduler/framework/parallelize"
+	"k8s.io/kubernetes/pkg/scheduler/util/assumecache"
 )
 
 // NodeScoreList declares a list of nodes and their scores.
@@ -701,6 +702,10 @@ type Handle interface {
 
 	SharedInformerFactory() informers.SharedInformerFactory
 
+	// ResourceClaimInfos returns an assume cache of ResourceClaim objects
+	// which gets populated by the shared informer factory.
+	ResourceClaimCache() *assumecache.AssumeCache
+
 	// RunFilterPluginsWithNominatedPods runs the set of configured filter plugins for nominated pod on the given node.
 	RunFilterPluginsWithNominatedPods(ctx context.Context, state *CycleState, pod *v1.Pod, info *NodeInfo) *Status
 

pkg/scheduler/framework/plugins/dynamicresources/dynamicresources.go

@@ -343,7 +343,6 @@ func New(ctx context.Context, plArgs runtime.Object, fh framework.Handle, fts fe
 		return &dynamicResources{}, nil
 	}
 
-	logger := klog.FromContext(ctx)
 	pl := &dynamicResources{
 		enabled:                    true,
 		fh:                         fh,
@@ -355,7 +354,7 @@ func New(ctx context.Context, plArgs runtime.Object, fh framework.Handle, fts fe
 		classParametersLister:      fh.SharedInformerFactory().Resource().V1alpha2().ResourceClassParameters().Lister(),
 		resourceSliceLister:        fh.SharedInformerFactory().Resource().V1alpha2().ResourceSlices().Lister(),
 		claimNameLookup:            resourceclaim.NewNameLookup(fh.ClientSet()),
-		claimAssumeCache:           assumecache.NewAssumeCache(logger, fh.SharedInformerFactory().Resource().V1alpha2().ResourceClaims().Informer(), "claim", "", nil),
+		claimAssumeCache:           fh.ResourceClaimCache(),
 	}
 
 	return pl, nil
@@ -597,21 +596,6 @@ func (pl *dynamicResources) isSchedulableAfterClaimChange(logger klog.Logger, po
 		//
 		// TODO (https://github.com/kubernetes/kubernetes/issues/123697):
 		// check that the pending claims depend on structured parameters (depends on refactoring foreachPodResourceClaim, see other TODO).
-		//
-		// There is a small race here:
-		// - The dynamicresources plugin allocates claim A and updates the assume cache.
-		// - A second pod gets marked as unschedulable based on that assume cache.
-		// - Before the informer cache here catches up, the pod runs, terminates and
-		//   the claim gets deallocated without ever sending the claim status with
-		//   allocation to the scheduler.
-		// - The comparison below is for a *very* old claim with no allocation and the
-		//   new claim where the allocation is already removed again, so no
-		//   RemovedClaimAllocation event gets emitted.
-		//
-		// This is extremely unlikely and thus a fix is not needed for alpha in Kubernetes 1.30.
-		// TODO (https://github.com/kubernetes/kubernetes/issues/123698): The solution is to somehow integrate the assume cache
-		// into the event mechanism. This can be tackled together with adding autoscaler
-		// support, which also needs to do something with the assume cache.
 		logger.V(6).Info("claim with structured parameters got deallocated", "pod", klog.KObj(pod), "claim", klog.KObj(modifiedClaim))
 		return framework.Queue, nil
 	}

pkg/scheduler/framework/plugins/dynamicresources/dynamicresources_test.go

@@ -44,6 +44,7 @@ import (
 	"k8s.io/kubernetes/pkg/scheduler/framework/plugins/feature"
 	"k8s.io/kubernetes/pkg/scheduler/framework/runtime"
 	st "k8s.io/kubernetes/pkg/scheduler/testing"
+	"k8s.io/kubernetes/pkg/scheduler/util/assumecache"
 	"k8s.io/kubernetes/test/utils/ktesting"
 	"k8s.io/utils/ptr"
 )
@@ -1319,10 +1320,11 @@ func setup(t *testing.T, nodes []*v1.Node, claims []*resourcev1alpha2.ResourceCl
 	tc.client.PrependReactor("list", "resourceclassparameters", createListReactor(tc.client.Tracker(), "ResourceClassParameters"))
 
 	tc.informerFactory = informers.NewSharedInformerFactory(tc.client, 0)
-
+	assumeCache := assumecache.NewAssumeCache(tCtx.Logger(), tc.informerFactory.Resource().V1alpha2().ResourceClaims().Informer(), "resource claim", "", nil)
 	opts := []runtime.Option{
 		runtime.WithClientSet(tc.client),
 		runtime.WithInformerFactory(tc.informerFactory),
+		runtime.WithResourceClaimCache(assumeCache),
 	}
 	fh, err := runtime.NewFramework(tCtx, nil, nil, opts...)
 	if err != nil {

pkg/scheduler/framework/runtime/framework.go

@@ -39,6 +39,7 @@ import (
 	"k8s.io/kubernetes/pkg/scheduler/framework"
 	"k8s.io/kubernetes/pkg/scheduler/framework/parallelize"
 	"k8s.io/kubernetes/pkg/scheduler/metrics"
+	"k8s.io/kubernetes/pkg/scheduler/util/assumecache"
 	"k8s.io/kubernetes/pkg/util/slice"
 )
 
@@ -71,11 +72,12 @@ type frameworkImpl struct {
 	// pluginsMap contains all plugins, by name.
 	pluginsMap map[string]framework.Plugin
 
-	clientSet       clientset.Interface
-	kubeConfig      *restclient.Config
-	eventRecorder   events.EventRecorder
-	informerFactory informers.SharedInformerFactory
-	logger          klog.Logger
+	clientSet          clientset.Interface
+	kubeConfig         *restclient.Config
+	eventRecorder      events.EventRecorder
+	informerFactory    informers.SharedInformerFactory
+	resourceClaimCache *assumecache.AssumeCache
+	logger             klog.Logger
 
 	metricsRecorder          *metrics.MetricAsyncRecorder
 	profileName              string
@@ -126,6 +128,7 @@ type frameworkOptions struct {
 	kubeConfig             *restclient.Config
 	eventRecorder          events.EventRecorder
 	informerFactory        informers.SharedInformerFactory
+	resourceClaimCache     *assumecache.AssumeCache
 	snapshotSharedLister   framework.SharedLister
 	metricsRecorder        *metrics.MetricAsyncRecorder
 	podNominator           framework.PodNominator
@@ -176,6 +179,13 @@ func WithInformerFactory(informerFactory informers.SharedInformerFactory) Option
 	}
 }
 
+// WithResourceClaimCache sets the resource claim cache for the scheduling frameworkImpl.
+func WithResourceClaimCache(resourceClaimCache *assumecache.AssumeCache) Option {
+	return func(o *frameworkOptions) {
+		o.resourceClaimCache = resourceClaimCache
+	}
+}
+
 // WithSnapshotSharedLister sets the SharedLister of the snapshot.
 func WithSnapshotSharedLister(snapshotSharedLister framework.SharedLister) Option {
 	return func(o *frameworkOptions) {
@@ -259,6 +269,7 @@ func NewFramework(ctx context.Context, r Registry, profile *config.KubeScheduler
 		kubeConfig:           options.kubeConfig,
 		eventRecorder:        options.eventRecorder,
 		informerFactory:      options.informerFactory,
+		resourceClaimCache:   options.resourceClaimCache,
 		metricsRecorder:      options.metricsRecorder,
 		extenders:            options.extenders,
 		PodNominator:         options.podNominator,
@@ -1598,6 +1609,10 @@ func (f *frameworkImpl) SharedInformerFactory() informers.SharedInformerFactory
 	return f.informerFactory
 }
 
+func (f *frameworkImpl) ResourceClaimCache() *assumecache.AssumeCache {
+	return f.resourceClaimCache
+}
+
 func (f *frameworkImpl) pluginsNeeded(plugins *config.Plugins) sets.Set[string] {
 	pgSet := sets.Set[string]{}
 

pkg/scheduler/scheduler.go

@@ -48,6 +48,7 @@ import (
 	internalqueue "k8s.io/kubernetes/pkg/scheduler/internal/queue"
 	"k8s.io/kubernetes/pkg/scheduler/metrics"
 	"k8s.io/kubernetes/pkg/scheduler/profile"
+	"k8s.io/kubernetes/pkg/scheduler/util/assumecache"
 )
 
 const (
@@ -293,11 +294,15 @@ func New(ctx context.Context,
 	snapshot := internalcache.NewEmptySnapshot()
 	metricsRecorder := metrics.NewMetricsAsyncRecorder(1000, time.Second, stopEverything)
 
+	resourceClaimInformer := informerFactory.Resource().V1alpha2().ResourceClaims().Informer()
+	resourceClaimCache := assumecache.NewAssumeCache(logger, resourceClaimInformer, "ResourceClaim", "", nil)
+
 	profiles, err := profile.NewMap(ctx, options.profiles, registry, recorderFactory,
 		frameworkruntime.WithComponentConfigVersion(options.componentConfigVersion),
 		frameworkruntime.WithClientSet(client),
 		frameworkruntime.WithKubeConfig(options.kubeConfig),
 		frameworkruntime.WithInformerFactory(informerFactory),
+		frameworkruntime.WithResourceClaimCache(resourceClaimCache),
 		frameworkruntime.WithSnapshotSharedLister(snapshot),
 		frameworkruntime.WithCaptureProfile(frameworkruntime.CaptureProfile(options.frameworkCapturer)),
 		frameworkruntime.WithParallelism(int(options.parallelism)),
@@ -356,7 +361,7 @@ func New(ctx context.Context,
 	sched.NextPod = podQueue.Pop
 	sched.applyDefaultHandlers()
 
-	if err = addAllEventHandlers(sched, informerFactory, dynInformerFactory, unionedGVKs(queueingHintsPerProfile)); err != nil {
+	if err = addAllEventHandlers(sched, informerFactory, dynInformerFactory, resourceClaimCache, unionedGVKs(queueingHintsPerProfile)); err != nil {
 		return nil, fmt.Errorf("adding event handlers: %w", err)
 	}