From 2998c795ed5f1accf041373c0b4cbf0883357862 Mon Sep 17 00:00:00 2001
From: Sean Mooney <work@seanmooney.info>
Date: Wed, 7 Aug 2019 20:05:08 +0100
Subject: [PATCH] add hw_pmu metadef

This change adds a new hw_pmu metadef property to the
OS::Compute::LibvirtImage namespace and extends the train
metadef changes releasenote.

Depends-on: https://review.opendev.org/#/c/671338/
Change-Id: I2f4e7ef4f816afbd0524a6265d5605afa1da5f86
---
 doc/source/admin/useful-image-properties.rst                | 5 +++++
 etc/metadefs/compute-libvirt-image.json                     | 6 ++++++
 .../notes/train-metadefs-changes-c4380754cdd13a19.yaml      | 2 ++
 3 files changed, 13 insertions(+)

diff --git a/doc/source/admin/useful-image-properties.rst b/doc/source/admin/useful-image-properties.rst
index 213f064cd3..9a9dbce42f 100644
--- a/doc/source/admin/useful-image-properties.rst
+++ b/doc/source/admin/useful-image-properties.rst
@@ -461,6 +461,11 @@ Here is a list of useful image properties and the values they expect.
        allows for flexibility in setting/overriding the default behavior as
        needed.
      - ``true`` or ``false``
+   * - libvirt API driver
+     - ``hw_pmu``
+     - Controls emulation of a virtual performance monitoring unit (vPMU) in the guest.
+       To reduce latency in realtime workloads disable the vPMU by setting hw_pmu=false.
+     - ``true`` or ``false``
    * - libvirt API driver
      - ``img_hide_hypervisor_id``
      - Some hypervisors add a signature to their guests.  While the presence
diff --git a/etc/metadefs/compute-libvirt-image.json b/etc/metadefs/compute-libvirt-image.json
index 5ef0b8c130..320223b80b 100644
--- a/etc/metadefs/compute-libvirt-image.json
+++ b/etc/metadefs/compute-libvirt-image.json
@@ -80,6 +80,12 @@
                 "virtio"
             ]
         },
+        "hw_pmu": {
+            "title": "Virtual Performance Monitoring Unit",
+            "description": "Controls emulation of a vPMU in the guest. To reduce latency in realtime workloads disable the vPMU by setting hw_pmu=false",
+            "type": "string",
+            "enum": ["true", "false"]
+        },
         "hw_qemu_guest_agent": {
             "title": "QEMU Guest Agent",
             "description": "This is a background process which helps management applications execute guest OS level commands. For example, freezing and thawing filesystems, entering suspend. However, guest agent (GA) is not bullet proof, and hostile guest OS can send spurious replies.",
diff --git a/releasenotes/notes/train-metadefs-changes-c4380754cdd13a19.yaml b/releasenotes/notes/train-metadefs-changes-c4380754cdd13a19.yaml
index 4359fa83f7..87ca881b04 100644
--- a/releasenotes/notes/train-metadefs-changes-c4380754cdd13a19.yaml
+++ b/releasenotes/notes/train-metadefs-changes-c4380754cdd13a19.yaml
@@ -4,6 +4,8 @@ upgrade:
     The following metadata definitions have been modified in the Train
     release:
 
+    * Added ``hw_pmu`` boolean in the ``OS::Compute::LibvirtImage`` namespace.
+
     * Added ``powervm`` to the ``hypervisor_type`` enumeration in the
       ``OS:::Compute::Hypervisor`` namespace.