tests/vm: Added configuration file support

Changes to tests/vm/basevm.py to allow accepting a configuration file
as a parameter. Allows for specifying VM options such as
cpu, machine, memory, and arbitrary qemu arguments for specifying options
such as NUMA configuration.
Also added an example conf_example_aarch64.yml and conf_example_x86.yml.

Signed-off-by: Robert Foley <robert.foley@linaro.org>
Reviewed-by: Peter Puhov <peter.puhov@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20200601211421.1277-4-robert.foley@linaro.org>
Message-Id: <20200701135652.1366-8-alex.bennee@linaro.org>

4 files changed, 146 insertions, 1 deletions

diff --git a/tests/vm/Makefile.include b/tests/vm/Makefile.include
index a253aba..f6c3892 100644
--- a/tests/vm/Makefile.include
+++ b/tests/vm/Makefile.include
@@ -44,6 +44,12 @@ endif
 	@echo "    QEMU_LOCAL=1                 - Use QEMU binary local to this build."
 	@echo "    QEMU=/path/to/qemu		 - Change path to QEMU binary"
 	@echo "    QEMU_IMG=/path/to/qemu-img	 - Change path to qemu-img tool"
+ifeq ($(PYTHON_YAML),yes)
+	@echo "    QEMU_CONFIG=/path/conf.yml   - Change path to VM configuration .yml file."
+else
+	@echo "    (install python3-yaml to enable support for yaml file to configure a VM.)"
+endif
+	@echo "                                   See conf_example_*.yml for file format details."
 
 vm-build-all: $(addprefix vm-build-, $(IMAGES))
 
diff --git a/tests/vm/basevm.py b/tests/vm/basevm.py
index 5ae39ad..f3a8fbb 100644
--- a/tests/vm/basevm.py
+++ b/tests/vm/basevm.py
@@ -481,7 +481,6 @@ class BaseVM(object):
                               cwd=cidir,
                               stdin=self._devnull, stdout=self._stdout,
                               stderr=self._stdout)
-
         return os.path.join(cidir, "cloud-init.iso")
 
 def get_qemu_path(arch, build_path=None):
@@ -497,6 +496,41 @@ def get_qemu_path(arch, build_path=None):
         qemu_path = "qemu-system-" + arch
     return qemu_path
 
+def parse_config(config, args):
+    """ Parse yaml config and populate our config structure.
+        The yaml config allows the user to override the
+        defaults for VM parameters.  In many cases these
+        defaults can be overridden without rebuilding the VM."""
+    if args.config:
+        config_file = args.config
+    elif 'QEMU_CONFIG' in os.environ:
+        config_file = os.environ['QEMU_CONFIG']
+    else:
+        return config
+    if not os.path.exists(config_file):
+        raise Exception("config file {} does not exist".format(config_file))
+    # We gracefully handle importing the yaml module
+    # since it might not be installed.
+    # If we are here it means the user supplied a .yml file,
+    # so if the yaml module is not installed we will exit with error.
+    try:
+        import yaml
+    except ImportError:
+        print("The python3-yaml package is needed "\
+              "to support config.yaml files")
+        # Instead of raising an exception we exit to avoid
+        # a raft of messy (expected) errors to stdout.
+        exit(1)
+    with open(config_file) as f:
+        yaml_dict = yaml.safe_load(f)
+
+    if 'qemu-conf' in yaml_dict:
+        config.update(yaml_dict['qemu-conf'])
+    else:
+        raise Exception("config file {} is not valid"\
+                        " missing qemu-conf".format(config_file))
+    return config
+
 def parse_args(vmcls):
 
     def get_default_jobs():
@@ -536,6 +570,9 @@ def parse_args(vmcls):
                       help="run tests with a snapshot")
     parser.add_option("--genisoimage", default="genisoimage",
                       help="iso imaging tool")
+    parser.add_option("--config", "-c", default=None,
+                      help="Provide config yaml for configuration. "\
+                           "See config_example.yaml for example.")
     parser.disable_interspersed_args()
     return parser.parse_args()
 
@@ -547,6 +584,7 @@ def main(vmcls, config=None):
         if not argv and not args.build_qemu and not args.build_image:
             print("Nothing to do?")
             return 1
+        config = parse_config(config, args)
         logging.basicConfig(level=(logging.DEBUG if args.debug
                                    else logging.WARN))
         vm = vmcls(args, config=config)
diff --git a/tests/vm/conf_example_aarch64.yml b/tests/vm/conf_example_aarch64.yml
new file mode 100644
index 0000000..9d44ae3
--- /dev/null
+++ b/tests/vm/conf_example_aarch64.yml
@@ -0,0 +1,51 @@
+#
+# Example yaml for use by any of the scripts in tests/vm.
+# Can be provided as an environment variable QEMU_CONFIG
+#
+qemu-conf:
+
+    # If any of the below are not provided, we will just use the qemu defaults.
+
+    # Login username and password(has to be sudo enabled)
+    guest_user: qemu
+    guest_pass: "qemupass"
+
+    # Password for root user can be different from guest.
+    root_pass: "qemupass"
+
+    # If one key is provided, both must be provided.
+    #ssh_key: /complete/path/of/your/keyfile/id_rsa
+    #ssh_pub_key: /complete/path/of/your/keyfile/id_rsa.pub
+
+    cpu: max
+    machine: virt,gic-version=max
+    memory: 16G
+
+    # The below is a example for how to configure NUMA topology with
+    # 4 NUMA nodes and 2 different NUMA distances.
+    qemu_args: "-smp cpus=16,sockets=2,cores=8
+                -numa node,cpus=0-3,nodeid=0 -numa node,cpus=4-7,nodeid=1
+                -numa node,cpus=8-11,nodeid=2 -numa node,cpus=12-15,nodeid=3
+                -numa dist,src=0,dst=1,val=15 -numa dist,src=2,dst=3,val=15
+                -numa dist,src=0,dst=2,val=20 -numa dist,src=0,dst=3,val=20
+                -numa dist,src=1,dst=2,val=20 -numa dist,src=1,dst=3,val=20"
+
+    # By default we do not set the DNS.
+    # You override the defaults by setting the below.
+    #dns: 1.234.567.89
+
+    # By default we will use a "block" device, but
+    # you can also boot from a "scsi" device.
+    # Just keep in mind your scripts might need to change
+    # As you will have /dev/sda instead of /dev/vda (for block device)
+    boot_dev_type: "block"
+
+    # By default the ssh port is not fixed.
+    # A fixed ssh port makes it easier for automated tests.
+    #ssh_port: 5555
+
+    # To install a different set of packages, provide a command to issue
+    #install_cmds: "apt-get update ; apt-get build-dep -y qemu"
+
+    # Or to skip the install entirely, just provide ""
+    #install_cmds: ""
diff --git a/tests/vm/conf_example_x86.yml b/tests/vm/conf_example_x86.yml
new file mode 100644
index 0000000..78d3f58
--- /dev/null
+++ b/tests/vm/conf_example_x86.yml
@@ -0,0 +1,50 @@
+#
+# Example yaml for use by any of the x86 based scripts in tests/vm.
+# Can be provided as an environment variable QEMU_CONFIG
+#
+qemu-conf:
+
+    # If any of the below are not provided, we will just use the qemu defaults.
+
+    # Login username and password(has to be sudo enabled)
+    guest_user: "qemu"
+    guest_pass: "qemupass"
+
+    # Password for root user can be different from guest.
+    root_pass: "qemupass"
+
+    # Provide default ssh keys of current user.
+    # You need to edit the below for your user.
+    #ssh_key_file: /home/<user>/.ssh/id_rsa
+    #ssh_pub_key_file: /home/<user>/.ssh/id_rsa.pub
+
+    cpu: max
+    machine: pc
+    memory: 8G
+
+    # The below is a example for how to configure NUMA topology with
+    # 4 NUMA nodes and 2 different NUMA distances.
+    qemu_args: "-smp cpus=8,sockets=2,cores=4
+                -object memory-backend-ram,size=4G,policy=bind,host-nodes=0,id=ram-node0
+                -object memory-backend-ram,size=4G,policy=bind,host-nodes=0,id=ram-node1
+                -object memory-backend-ram,size=4G,policy=bind,host-nodes=1,id=ram-node2
+                -object memory-backend-ram,size=4G,policy=bind,host-nodes=1,id=ram-node3
+                -numa node,cpus=0-1,nodeid=0 -numa node,cpus=2-3,nodeid=1
+                -numa node,cpus=4-5,nodeid=2 -numa node,cpus=6-7,nodeid=3
+                -numa dist,src=0,dst=1,val=15 -numa dist,src=2,dst=3,val=15
+                -numa dist,src=0,dst=2,val=20 -numa dist,src=0,dst=3,val=20
+                -numa dist,src=1,dst=2,val=20 -numa dist,src=1,dst=3,val=20"
+
+    # By default we do not set the DNS.
+    # You override the defaults by setting the below.
+    #dns: "1.234.567.89"
+
+    # By default we will use a "block" device, but
+    # you can also boot from a "scsi" device.
+    # Just keep in mind your scripts might need to change
+    # As you will have /dev/sda instead of /dev/vda (for block device)
+    boot_dev_type: "block"
+
+    # By default the ssh port is not fixed.
+    # A fixed ssh port makes it easier for automated tests.
+    ssh_port: 5555