Allow additional dpdk runtime libraries to be installed

Only some dpdk runtime libraries are installed by default, but some
environments may need additional libraries installed. This adds an
option to allow the user to specify additional dpdk runtime libraries
via a config option `dpdk-runtime-libraries`.

Closes-Bug: #1936850

config.yaml

@@ -124,6 +124,21 @@ options:
         uio_pci_generic
       .
       Only used when DPDK is enabled.
+  dpdk-runtime-libraries:
+    type: string
+    default:
+    description: |
+      Space delimited list of additional DPDK runtime libraries that should
+      be installed when DPDK is enabled.
+      .
+      By default, only the runtime libraries that are recommended with the
+      dpdk libraries are installed. Environments that need additional libraries
+      installed should include those library packages. For example, to enable
+      the pmd-bnx2x runtime library specify the name of the software package
+      `librte-pmd-bnx2x20.0`. To enable the pmd-bnx2x and the pmd-ice runtime
+      libraries, specify the value as `librte-pmd-bnx2x20.0 librte-pmd-ice20.0`.
+      .
+      Only used when DPDK is enabled.
   enable-hardware-offload:
     type: boolean
     default: false

lib/charms/ovn_charm.py

@@ -300,6 +300,21 @@ def enable_openstack(self):
         """
         return reactive.is_flag_set('charm.ovn-chassis.enable-openstack')
 
+    @property
+    def additional_dpdk_libraries(self):
+        """A list of additional runtime libraries to be installed for dpdk.
+
+        :returns: list of additional packages to install
+        :rtype: List[str]
+        """
+        if self.options.enable_dpdk and self.options.dpdk_runtime_libraries:
+            # dpdk_runtime_libraries is a space delimited list of strings.
+            # some options are disabled by passing 'None' so filter out a
+            # specifying of a 'None' value
+            return list(filter(lambda x: x and x.lower() != 'none',
+                               self.options.dpdk_runtime_libraries.split()))
+        return []
+
     @property
     def packages(self):
         """Full list of packages to be installed.
@@ -310,6 +325,7 @@ def packages(self):
         _packages = ['ovn-host']
         if self.options.enable_dpdk:
             _packages.extend(['openvswitch-switch-dpdk'])
+            _packages.extend(self.additional_dpdk_libraries)
         if self.options.enable_hardware_offload or self.options.enable_sriov:
             # The ``sriov-netplan-shim`` package does boot-time
             # configuration of Virtual Functions (VFs) in the system.

unit_tests/test_lib_charms_ovn_charm.py

@@ -442,6 +442,27 @@ def test_optional_openstack_metadata_wallaby(self):
             'neutron-ovn-metadata-agent'])
 
 
+class TestDPDKOVNChassisCharmExtraLibs(Helper):
+
+    def setUp(self):
+        super().setUp(config={
+            'enable-hardware-offload': False,
+            'enable-sriov': False,
+            'enable-dpdk': True,
+            'dpdk-bond-mappings': ('dpdk-bond0:a0:36:9f:dd:37:a4 '
+                                   'dpdk-bond0:a0:36:9f:dd:3e:9c'),
+            'bridge-interface-mappings': 'br-ex:eth0 br-data:dpdk-bond0',
+            'ovn-bridge-mappings': (
+                'provider:br-ex other:br-data'),
+            'prefer-chassis-as-gw': False,
+            'dpdk-runtime-libraries': 'librte-pmd-hinic20.0 None',
+        })
+
+    def test__init__(self):
+        self.assertEquals(self.target.packages, [
+            'ovn-host', 'openvswitch-switch-dpdk', 'librte-pmd-hinic20.0'])
+
+
 class TestDPDKOVNChassisCharm(Helper):
 
     def setUp(self):
@@ -455,6 +476,7 @@ def setUp(self):
             'ovn-bridge-mappings': (
                 'provider:br-ex other:br-data'),
             'prefer-chassis-as-gw': False,
+            'dpdk-runtime-libraries': '',
         })
 
     def test__init__(self):