Create functional integration tests for hotplugging

Create some functional integration tests for hotplugging. Covering
positive and negative cases, as well as onlining of vCPUs

Signed-off-by: James Curtis <jxcurtis@amazon.co.uk>

tests/integration_tests/functional/test_vcpu_hotplug.py

@@ -0,0 +1,117 @@
+# Copyright 2024 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+"""Integration tests for hotplugging vCPUs"""
+
+import platform
+import re
+import time
+
+import pytest
+
+from framework.defs import MAX_SUPPORTED_VCPUS
+from framework.utils_cpuid import check_guest_cpuid_output
+
+
+@pytest.mark.skipif(
+ platform.machine() != "x86_64", reason="Hotplug only enabled on x86_64."
+)
+@pytest.mark.parametrize("vcpu_count", [1, MAX_SUPPORTED_VCPUS - 1])
+def test_hotplug_vcpus(uvm_plain, vcpu_count):
+ """Test hotplugging works as intended"""
+ uvm_plain.jailer.extra_args.update({"no-seccomp": None})
+ uvm_plain.spawn()
+ uvm_plain.basic_config(vcpu_count=1, mem_size_mib=128)
+ uvm_plain.add_net_iface()
+ uvm_plain.start()
+ uvm_plain.wait_for_up()
+
+ uvm_plain.api.hotplug.put(Vcpu={"add": vcpu_count})
+
+ time.sleep(1)
+
+ check_guest_cpuid_output(
+ uvm_plain,
+ "lscpu",
+ None,
+ ":",
+ {
+ "CPU(s)": str(1 + vcpu_count),
+ "Off-line CPU(s) list": "1" if vcpu_count == 1 else f"1-{vcpu_count}",
+ },
+ )
+
+
+@pytest.mark.skipif(
+ platform.machine() != "x86_64", reason="Hotplug only enabled on x86_64."
+)
+@pytest.mark.parametrize(
+ "vcpu_count", [-1, 0, MAX_SUPPORTED_VCPUS, MAX_SUPPORTED_VCPUS + 1]
+)
+def test_negative_hotplug_vcpus(uvm_plain, vcpu_count):
+ """Test cases where hotplugging should fail."""
+ uvm_plain.jailer.extra_args.update({"no-seccomp": None})
+ uvm_plain.spawn()
+ uvm_plain.basic_config(vcpu_count=1, mem_size_mib=128)
+ uvm_plain.start()
+
+ # Need to allow time for VM to finish starting before API call is made
+ time.sleep(0.5)
+
+ if vcpu_count == 0:
+ with pytest.raises(
+ RuntimeError,
+ match="Hotplug error: Vcpu hotplugging error: The number of vCPUs added must be greater than 0.",
+ ):
+ uvm_plain.api.hotplug.put(Vcpu={"add": vcpu_count})
+ elif vcpu_count < 0:
+ with pytest.raises(
+ RuntimeError,
+ match=re.compile(
+ "An error occurred when deserializing the json body of a request: invalid value: integer `-\\d+`, expected u8+"
+ ),
+ ):
+ uvm_plain.api.hotplug.put(Vcpu={"add": vcpu_count})
+ elif vcpu_count > 31:
+ with pytest.raises(
+ RuntimeError,
+ match="Hotplug error: Vcpu hotplugging error: The number of vCPUs added must be less than 32.",
+ ):
+ uvm_plain.api.hotplug.put(Vcpu={"add": vcpu_count})
+
+
+@pytest.mark.skipif(
+ platform.machine() != "x86_64", reason="Hotplug only enabled on x86_64."
+)
+@pytest.mark.parametrize("vcpu_count", [1, MAX_SUPPORTED_VCPUS - 1])
+def test_online_hotplugged_vcpus(uvm_plain, vcpu_count):
+ """Test that hotplugged CPUs can be onlined"""
+ uvm_plain.jailer.extra_args.update({"no-seccomp": None})
+ uvm_plain.spawn()
+ uvm_plain.basic_config(vcpu_count=1, mem_size_mib=128)
+ uvm_plain.add_net_iface()
+ uvm_plain.start()
+ uvm_plain.wait_for_up()
+
+ uvm_plain.api.hotplug.put(Vcpu={"add": vcpu_count})
+
+ time.sleep(1)
+
+ _, _, stderr = uvm_plain.ssh.run(
+ f"for i in {{1..{vcpu_count}}}; do echo 1 > /sys/devices/system/cpu/cpu$i/online; done"
+ )
+
+ assert stderr == ""
+
+ time.sleep(5)
+
+ check_guest_cpuid_output(
+ uvm_plain,
+ "lscpu",
+ None,
+ ":",
+ {
+ "CPU(s)": str(1 + vcpu_count),
+ "On-line CPU(s) list": "0,1" if vcpu_count == 1 else f"0-{vcpu_count}",
+ },
+ )