Merge pull request #60519 from bsalamat/auto_prio_class

Automatic merge from submit-queue (batch tested with PRs 60519, 61099, 61218, 61166, 61714). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Automatically add system critical priority classes at cluster boostrapping

**What this PR does / why we need it**:
We had two PriorityClasses that were hardcoded and special cased in our code base. These two priority classes never existed in API server. Priority admission controller had code to resolve these two names. This PR removes the hardcoded PriorityClasses and adds code to create these PriorityClasses automatically when API server starts.

**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #60178

ref/ #57471

**Special notes for your reviewer**:

**Release note**:

```release-note
Automatically add system critical priority classes at cluster boostrapping.
```

/sig scheduling

test/e2e/scheduling/BUILD

@@ -22,10 +22,10 @@ go_library(
         "//pkg/api/v1/pod:go_default_library",
         "//pkg/apis/core:go_default_library",
         "//pkg/apis/extensions:go_default_library",
+        "//pkg/apis/scheduling:go_default_library",
         "//pkg/kubelet/apis:go_default_library",
         "//pkg/quota/evaluator/core:go_default_library",
         "//pkg/scheduler/algorithm/priorities/util:go_default_library",
-        "//pkg/scheduler/api:go_default_library",
         "//pkg/util/version:go_default_library",
         "//test/e2e/common:go_default_library",
         "//test/e2e/framework:go_default_library",

test/e2e/scheduling/preemption.go

@@ -26,7 +26,7 @@ import (
 	"k8s.io/apimachinery/pkg/api/resource"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	clientset "k8s.io/client-go/kubernetes"
-	schedulerapi "k8s.io/kubernetes/pkg/scheduler/api"
+	"k8s.io/kubernetes/pkg/apis/scheduling"
 	"k8s.io/kubernetes/test/e2e/framework"
 
 	. "github.com/onsi/ginkgo"
@@ -168,7 +168,7 @@ var _ = SIGDescribe("SchedulerPreemption [Serial] [Feature:PodPreemption]", func
 		// Create a critical pod and make sure it is scheduled.
 		runPausePod(f, pausePodConfig{
 			Name:              "critical-pod",
-			PriorityClassName: schedulerapi.SystemClusterCritical,
+			PriorityClassName: scheduling.SystemClusterCritical,
 			Resources: &v1.ResourceRequirements{
 				Requests: podRes,
 			},
@@ -311,3 +311,34 @@ var _ = SIGDescribe("SchedulerPreemption [Serial] [Feature:PodPreemption]", func
 		}
 	})
 })
+
+var _ = SIGDescribe("PodPriorityResolution [Serial] [Feature:PodPreemption]", func() {
+	var cs clientset.Interface
+	var ns string
+	f := framework.NewDefaultFramework("sched-pod-priority")
+
+	BeforeEach(func() {
+		cs = f.ClientSet
+		ns = f.Namespace.Name
+
+		err := framework.CheckTestingNSDeletedExcept(cs, ns)
+		framework.ExpectNoError(err)
+	})
+
+	// This test verifies that system critical priorities are created automatically and resolved properly.
+	It("validates critical system priorities are created and resolved", func() {
+		// Create pods that use system critical priorities and
+		By("Create pods that use critical system priorities.")
+		systemPriorityClasses := []string{
+			scheduling.SystemNodeCritical, scheduling.SystemClusterCritical,
+		}
+		for i, spc := range systemPriorityClasses {
+			pod := createPausePod(f, pausePodConfig{
+				Name:              fmt.Sprintf("pod%d-%v", i, spc),
+				PriorityClassName: spc,
+			})
+			Expect(pod.Spec.Priority).NotTo(BeNil())
+			framework.Logf("Created pod: %v", pod.Name)
+		}
+	})
+})