WIP: kubelet: add a way to toggle the devicemanager check

Signed-off-by: Francesco Romani <fromani@redhat.com>

pkg/kubelet/cm/devicemanager/manager.go

@@ -546,6 +546,11 @@ func (m *ManagerImpl) devicesToAllocate(podUID, contName, resource string, requi
 	}
 
 	klog.V(3).InfoS("Need devices to allocate for pod", "deviceNumber", needed, "resourceName", resource, "podUID", string(podUID), "containerName", contName)
+	if IsRelaxedCheckEnabled() && needed == 0 {
+		// No change, no work.
+		return nil, nil
+	}
+
 	healthyDevices, hasRegistered := m.healthyDevices[resource]
 
 	// Check if resource registered with devicemanager

pkg/kubelet/cm/devicemanager/strictallocation.go

@@ -0,0 +1,38 @@
+/*
+Copyright 2023 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 devicemanager
+
+import "os"
+
+var (
+	devicemanagerRelaxedCheckEnabled  bool
+	devicemanagerRelaxedCheckFilename = "/etc/kubernetes/openshift-devicemanager-relaxed-check"
+)
+
+func init() {
+	readEnablementFile()
+}
+
+func readEnablementFile() {
+	if _, err := os.Stat(devicemanagerRelaxedCheckFilename); err == nil {
+		devicemanagerRelaxedCheckEnabled = true
+	}
+}
+
+func IsRelaxedCheckEnabled() bool {
+	return devicemanagerRelaxedCheckEnabled
+}