feat(TaskRunSpec) : Add SchedulerName to TaskRunSpec

docs/podtemplates.md

@@ -46,6 +46,10 @@ The current fields supported are:
   [priority class](https://kubernetes.io/docs/concepts/configuration/pod-priority-preemption/)
   to use when running the pod. Use this, for example, to selectively enable
   preemption on lower priority workloads.
+  - `schedulerName` the name of the [scheduler](https://kubernetes.io/docs/tasks/administer-cluster/configure-multiple-schedulers/)
+  to use when dispatching the Pod. This can be used when workloads of specific types need specific schedulers,
+  eg: If you are using volcano.sh for Machine Learning Workloads, you can pass the schedulerName and have Tasks be 
+  dispatched by the volcano.sh scheduler.
 
 
 A pod template can be specified for `TaskRun` or `PipelineRun` resources.

docs/taskruns.md

@@ -192,7 +192,8 @@ allows to customize some Pod specific field per `Task` execution, aka `TaskRun`.
 
 In the following example, the Task is defined with a `volumeMount`
 (`my-cache`), that is provided by the TaskRun, using a
-PersistenceVolumeClaim. The Pod will also run as a non-root user.
+PersistenceVolumeClaim. The SchedulerName has also been provided to define which scheduler should be used to
+dispatch the Pod. The Pod will also run as a non-root user.
 
 ```yaml
 apiVersion: tekton.dev/v1alpha1
@@ -219,6 +220,7 @@ spec:
   taskRef:
     name: mytask
   podTemplate:
+    schedulerName: volcano
     securityContext:
       runAsNonRoot: true
     volumes:

pkg/apis/pipeline/pod/template.go

@@ -90,6 +90,9 @@ type Template struct {
 	// default.
 	// +optional
 	PriorityClassName *string `json:"priorityClassName,omitempty" protobuf:"bytes,7,opt,name=priorityClassName"`
+	// SchedulerName specifies the scheduler to be used to dispatch the Pod
+	// +optional
+	SchedulerName string `json:"schedulerName"`
 }
 
 func (tpl *Template) Equals(other *Template) bool {

pkg/pod/pod.go

@@ -238,6 +238,7 @@ func MakePod(images pipeline.Images, taskRun *v1alpha1.TaskRun, taskSpec v1alpha
 			SecurityContext:              podTemplate.SecurityContext,
 			RuntimeClassName:             podTemplate.RuntimeClassName,
 			AutomountServiceAccountToken: podTemplate.AutomountServiceAccountToken,
+			SchedulerName:                podTemplate.SchedulerName,
 			DNSPolicy:                    dnsPolicy,
 			DNSConfig:                    podTemplate.DNSConfig,
 			EnableServiceLinks:           podTemplate.EnableServiceLinks,

pkg/pod/pod_test.go

@@ -673,6 +673,54 @@ script-heredoc-randomly-generated-78c5n
 			}},
 			Volumes: append(implicitVolumes, scriptsVolume, toolsVolume, downwardVolume),
 		},
+	}, {
+		desc: "using another scheduler",
+		ts: v1alpha1.TaskSpec{
+			TaskSpec: v1alpha2.TaskSpec{
+				Steps: []v1alpha1.Step{
+					{
+						Container: corev1.Container{
+							Name:    "schedule-me",
+							Image:   "image",
+							Command: []string{"cmd"}, // avoid entrypoint lookup.
+						},
+					},
+				},
+			},
+		},
+		trs: v1alpha1.TaskRunSpec{
+			PodTemplate: &v1alpha1.PodTemplate{
+				SchedulerName: "there-scheduler",
+			},
+		},
+		want: &corev1.PodSpec{
+			RestartPolicy:  corev1.RestartPolicyNever,
+			InitContainers: []corev1.Container{placeToolsInit},
+			SchedulerName:  "there-scheduler",
+			Volumes:        append(implicitVolumes, toolsVolume, downwardVolume),
+			Containers: []corev1.Container{{
+				Name:    "step-schedule-me",
+				Image:   "image",
+				Command: []string{"/tekton/tools/entrypoint"},
+				Args: []string{
+					"-wait_file",
+					"/tekton/downward/ready",
+					"-wait_file_content",
+					"-post_file",
+					"/tekton/tools/0",
+					"-termination_path",
+					"/tekton/termination",
+					"-entrypoint",
+					"cmd",
+					"--",
+				},
+				Env:                    implicitEnvVars,
+				VolumeMounts:           append([]corev1.VolumeMount{toolsMount, downwardMount}, implicitVolumeMounts...),
+				WorkingDir:             pipeline.WorkspaceDir,
+				Resources:              corev1.ResourceRequirements{Requests: allZeroQty()},
+				TerminationMessagePath: "/tekton/termination",
+			}},
+		},
 	}} {
 		t.Run(c.desc, func(t *testing.T) {
 			names.TestingSeed()