Request for sending data via telemetry

The goal is to collect metrics about Pods that would fail if SELinuxMount feature gate gets enabled.

The feature gate is off by default and it's part of the TechPreviewNoUpgrade feature set. This feature gate changes how SELinux is applied to Pod volumes and some Pods may not start. Kubernetes collect metrics about such pods before the feature gate is enabled and we want the metrics in telemetry. See upstream KEP for details.

(We already have a few metrics in telemetry, this is a new one).

cluster:selinux_warning_controller_selinux_volume_conflict:total

cluster:selinux_warning_controller_selinux_volume_conflict:total represents number of pods that may fail to start when SELinuxMount feature gate is enabled and Pods caught by this metric land on the same node.

Labels

• "property", possible values are "SELinuxLabel" and "SELinuxChangePolicy"

The cardinality of the metric is at most 2.

Component exposing the metric: kube-controller-manager, aggregated by a rule created by github.com/openshift/cluster-storage-operator (PR) 

For the record, I will need it in 4.20. Based on the current stage, most probably like a bugfix / backport from 4.21.