[PATCH] KVM test: Add cpu_set subtest

[PATCH] KVM test: Add cpu_set subtest

[Lucas Meneghel Rodrigues]

Tests the ability of adding virtual cpus on the fly to qemu using
the monitor command cpu_set, then after everything is OK, run the
cpu_hotplug testsuite on the guest through autotest.

Updates: The cpu_set feature has been worked out and is in
better shape, however it is my understanding that SeaBIOS code
has to be extended to support cpu_hotplug, like bochs bios did.

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
---
 client/tests/kvm/tests/cpu_set.py      |   95 ++++++++++++++++++++++++++++++++
 client/tests/kvm/tests_base.cfg.sample |    7 ++
 2 files changed, 102 insertions(+), 0 deletions(-)
 create mode 100644 client/tests/kvm/tests/cpu_set.py

diff --git a/client/tests/kvm/tests/cpu_set.py b/client/tests/kvm/tests/cpu_set.py
new file mode 100644
index 0000000..e79fc95
--- /dev/null
+++ b/client/tests/kvm/tests/cpu_set.py
@@ -0,0 +1,95 @@
+import os, logging, re
+from autotest_lib.client.common_lib import error
+import kvm_test_utils
+
+def run_cpu_set(test, params, env):
+    """
+    Runs CPU set test:
+
+    1) Pick up a living guest
+    2) Send the monitor command cpu_set [n cpus]
+    3) Verify if guest has the additional CPU showing up under
+        /sys/devices/system/cpu
+    4) Try to bring it online by writing 1 to the 'online' file inside that dir
+    5) Run the CPU Hotplug test suite shipped with autotest inside guest
+
+    @param test: kvm test object.
+    @param params: Dictionary with test parameters.
+    @param env: Dictionary with the test environment.
+    """
+    vm = kvm_test_utils.get_living_vm(env, params.get("main_vm"))
+    session = kvm_test_utils.wait_for_login(vm)
+
+    n_cpus_add = int(params.get("n_cpus_add", 1))
+    current_cpus = int(params.get("smp", 1))
+    total_cpus = current_cpus + n_cpus_add
+    # Let's define some boundaries for this test
+    if total_cpus > 100:
+        raise error.TestError("Unsupported number of total CPUs: %s" %
+                              total_cpus)
+
+    dmesg_before = session.get_command_output("dmesg -c")
+
+    logging.info("Adding %d CPUs to guest", n_cpus_add)
+    for i in range(total_cpus):
+        status, output = vm.send_monitor_cmd("cpu_set %s online" % i)
+        if status != 0:
+            raise error.TestFail("Failed to add CPU %s to guest: %s" %
+                                 (i, output))
+
+    status, output = vm.send_monitor_cmd("info cpus")
+    logging.debug("Output of info cpus:\n%s", output)
+    cpu_regexp = re.compile("CPU #(\d+)")
+    total_cpus_monitor = len(cpu_regexp.findall(output))
+    if total_cpus_monitor != total_cpus:
+        raise error.TestFail("Monitor reports %s CPUs, when VM should have %s" %
+                             (total_cpus_monitor, total_cpus))
+
+    dmesg_after = session.get_command_output("dmesg -c")
+    logging.debug("Guest dmesg output after CPU add:\n%s" % dmesg_after)
+
+    # Verify whether the new cpus are showing up on /sys
+    n_cmd = 'find /sys/devices/system/cpu/cpu[0-99] -maxdepth 0 -type d | wc -l'
+    output = session.get_command_output(n_cmd)
+    try:
+        cpus_after_addition = int(output)
+    except ValueError:
+        logging.error("Verify command output: %s", output)
+        raise error.TestFail("Unable to get CPU count after CPU addition")
+
+    if cpus_after_addition != total_cpus:
+        raise error.TestFail("%s CPUs are showing up under "
+                             "/sys/devices/system/cpu, was expecting %s" %
+                             (cpus_after_addition, total_cpus))
+
+    r_cmd = 'find /sys/devices/system/cpu/cpu[0-99]/online -maxdepth 0 -type f'
+    online_files = session.get_command_output(r_cmd).split().sort()
+
+    if not online_files:
+        raise error.TestFail("Could not find CPUs that can be "
+                             "enabled/disabled on guest")
+
+    for online_file in online_files:
+        cpu_regexp = re.compile("cpu(\d+)", re.IGNORECASE)
+        cpu_id = cpu_regexp.findall(online_file)[0]
+        try:
+            check_online_status = int(session.get_command_output("cat %s" %
+                                                                 online_file))
+        except ValueError:
+            raise error.TestFail("Unable to get online status from CPU %s" %
+                                 cpu_id)
+        if check_online_status == 0:
+            logging.debug("CPU %s offline, bringing it online" % cpu_id)
+            bring_online_status = session.get_command_status("echo 1 > %s" %
+                                                             online_file)
+            if bring_online_status != 0:
+                raise error.TestError("Error bringing guest CPU %s online" %
+                                      cpu_id)
+
+    # Now that all CPUs were onlined, let's execute the
+    # autotest CPU Hotplug test
+    control_path = os.path.join(test.bindir, "autotest_control",
+                                "cpu_hotplug.control")
+    kvm_test_utils.run_autotest(vm, session, control_path,
+                                int(params.get("cpu_hotplug_timeout")),
+                                test.outputdir)
diff --git a/client/tests/kvm/tests_base.cfg.sample b/client/tests/kvm/tests_base.cfg.sample
index e73ba44..6f769e6 100644
--- a/client/tests/kvm/tests_base.cfg.sample
+++ b/client/tests/kvm/tests_base.cfg.sample
@@ -348,6 +348,13 @@ variants:
                 image_name_snapshot1 = sn1
                 image_name_snapshot2 = sn2
 
+    - cpu_set:
+        type = cpu_set
+        cpu_hotplug_timeout = 600
+        n_cpus_add = 1
+        kill_vm = yes
+        iterations = 5
+
     # system_powerdown, system_reset and shutdown *must* be the last ones
     # defined (in this order), since the effect of such tests can leave
     # the VM on a bad state.
-- 
1.6.6.1