Add doc for k8s intel gpu device plugin under operations

Patchset 3: reST formatting, minor grammar and capitalization, typo
Patchset 6: minor grammar edits
Patchset 7: Wording updates per feedback

Story: 2005937
Task: 37644

Change-Id: I65c5fd9be894b5de5132af43daba202496b6654e
Signed-off-by: SidneyAn <ran1.an@intel.com>
Signed-off-by: Kristal Dale <kristal.dale@intel.com>

doc/source/operations/index.rst

@@ -33,6 +33,7 @@ Kubernetes Operation
    k8s_persistent_vol_claims
    k8s_sriov_config
    k8s_qat_device_plugin
+   k8s_gpu_device_plugin
 
 -------------------
 OpenStack Operation

doc/source/operations/k8s_gpu_device_plugin.rst

@@ -0,0 +1,77 @@
+================================================
+Kubernetes Intel GPU Device Plugin Configuration
+================================================
+
+This document describes how to enable the Intel GPU device plugin in StarlingX
+and schedule pods on nodes with an Intel GPU.
+
+------------------------------
+Enable Intel GPU device plugin
+------------------------------
+
+You can pre-install the ``intel-gpu-plugin`` daemonset as follows:
+
+#. Launch the ``intel-gpu-plugin`` daemonset.
+
+   Add the following lines to the ``localhost.yaml`` file before playing the
+   Ansible bootstrap playbook to configure the system.
+
+   ::
+
+     k8s_plugins:
+       intel-gpu-plugin: intelgpu=enabled
+
+#. Assign the ``intelgpu`` label to each node that should have the Intel GPU
+   plugin enabled. This will make any GPU devices on a given node available for
+   scheduling to containers. The following example assigns the ``intelgpu``
+   label to the compute-0 node.
+
+   ::
+
+      $ NODE=compute-0
+      $ system host-lock $NODE
+      $ system host-label-assign $NODE intelgpu=enabled
+      $ system host-unlock $NODE
+
+#. After the node becomes available, verify the GPU device plugin is registered
+   and that the available GPU devices on the node have been discovered and reported.
+
+   ::
+
+      $ kubectl describe node $NODE | grep gpu.intel.com
+      gpu.intel.com/i915:  1
+      gpu.intel.com/i915:  1
+
+-------------------------------------
+Schedule pods on nodes with Intel GPU
+-------------------------------------
+
+Add a ``resources.limits.gpu.intel.com`` to your container specification in order
+to request an available GPU device for your container.
+
+::
+
+  ...
+  spec:
+    containers:
+      - name: ...
+        ...
+        resources:
+          limits:
+            gpu.intel.com/i915: 1
+
+
+The pods will be scheduled to the nodes with available Intel GPU devices. A GPU
+device will be allocated to the container and the available GPU devices will be
+updated.
+
+::
+
+      $ kubectl describe node $NODE | grep gpu.intel.com
+      gpu.intel.com/i915:  1
+      gpu.intel.com/i915:  0
+
+For more details, refer to the following examples:
+
+* `Kubernetes manifest file example <https://github.com/intel/intel-device-plugins-for-kubernetes/blob/master/demo/intelgpu-job.yaml>`_
+* `Scheduling pods on nodes with Intel GPU example <https://github.com/intel/intel-device-plugins-for-kubernetes/blob/master/cmd/gpu_plugin/README.md#test-gpu-device-plugin>`_