[PATCH] KVM test: Measure the timedrift after continuing a stopped vm

[Jason Wang <jasowang@redhat.com>]

This test extends the timedifrt test and measures the timedirft across
the vm stopping and continuing. Two helpers function are also added in
kvm_test_utils to do the stop and continue.

Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 client/tests/kvm/tests/timedrift_with_stop.py |   97 +++++++++++++++++++++++++
 1 files changed, 97 insertions(+), 0 deletions(-)
 create mode 100644 client/tests/kvm/tests/timedrift_with_stop.py

diff --git a/client/tests/kvm/kvm_test_utils.py b/client/tests/kvm/kvm_test_utils.py
index 24e2bf5..7e158a3 100644
--- a/client/tests/kvm/kvm_test_utils.py
+++ b/client/tests/kvm/kvm_test_utils.py
@@ -181,6 +181,30 @@ def migrate(vm, env=None):
         raise
 
 
+def stop(vm):
+    """
+    Stop a running vm
+    """
+    s, o = vm.send_monitor_cmd("stop")
+    if s != 0:
+        raise error.TestError("Could not send the stop command")
+    s, o = vm.send_monitor_cmd("info status")
+    if "paused" not in o:
+        raise error.TestFail("VM does not stop afer send stop command")
+
+    
+def cont(vm):
+    """
+    Continue a stopped vm
+    """
+    s, o = vm.send_monitor_cmd("cont")
+    if s != 0:
+        raise error.TestError("Could not send the cont command")
+    s, o = vm.send_monitor_cmd("info status")
+    if "running" not in o:
+        raise error.TestFail("VM still in paused status after sending cont")
+    
+
 def get_time(session, time_command, time_filter_re, time_format):
     """
     Return the host time and guest time.  If the guest time cannot be fetched
diff --git a/client/tests/kvm/tests/timedrift_with_stop.py b/client/tests/kvm/tests/timedrift_with_stop.py
new file mode 100644
index 0000000..b99dd40
--- /dev/null
+++ b/client/tests/kvm/tests/timedrift_with_stop.py
@@ -0,0 +1,97 @@
+import logging, time, commands, re
+from autotest_lib.client.common_lib import error
+import kvm_subprocess, kvm_test_utils, kvm_utils
+
+
+def run_timedrift_with_stop(test, params, env):
+    """
+    Time drift test with stop/continue the guest:
+
+    1) Log into a guest.
+    2) Take a time reading from the guest and host.
+    3) Stop the running of the guest
+    4) Sleep for a while
+    5) Continue the guest running
+    6) Take a second time reading.
+    7) If the drift (in seconds) is higher than a user specified value, fail.
+
+    @param test: KVM test object.
+    @param params: Dictionary with test parameters.
+    @param env: Dictionary with the test environment.
+    """
+    login_timeout = int(params.get("login_timeout", 360))
+    vm = kvm_test_utils.get_living_vm(env, params.get("main_vm"))
+    session = kvm_test_utils.wait_for_login(vm, timeout=login_timeout)
+
+    # Collect test parameters:
+    # Command to run to get the current time
+    time_command = params.get("time_command")
+    # Filter which should match a string to be passed to time.strptime()
+    time_filter_re = params.get("time_filter_re")
+    # Time format for time.strptime()
+    time_format = params.get("time_format")
+    drift_threshold = float(params.get("drift_threshold", "10"))
+    drift_threshold_single = float(params.get("drift_threshold_single", "3"))
+    stop_iterations = int(params.get("stop_iterations", 1))
+    stop_time = int(params.get("stop_time", 60))
+
+    try:
+        # Get initial time
+        # (ht stands for host time, gt stands for guest time)
+        (ht0, gt0) = kvm_test_utils.get_time(session, time_command,
+                                             time_filter_re, time_format)
+
+        # Stop the guest
+        for i in range(stop_iterations):
+            # Get time before current iteration
+            (ht0_, gt0_) = kvm_test_utils.get_time(session, time_command,
+                                                   time_filter_re, time_format)
+            # Run current iteration
+            logging.info("Stop %s second: iteration %d of %d..." %
+                         (stop_time, i + 1, stop_iterations))
+            
+            kvm_test_utils.stop(vm)
+            time.sleep(stop_time)
+            kvm_test_utils.cont(vm)
+            
+            # Get time after current iteration
+            (ht1_, gt1_) = kvm_test_utils.get_time(session, time_command,
+                                                   time_filter_re, time_format)
+            # Report iteration results
+            host_delta = ht1_ - ht0_
+            guest_delta = gt1_ - gt0_
+            drift = abs(host_delta - guest_delta)
+            logging.info("Host duration (iteration %d): %.2f" %
+                         (i + 1, host_delta))
+            logging.info("Guest duration (iteration %d): %.2f" %
+                         (i + 1, guest_delta))
+            logging.info("Drift at iteration %d: %.2f seconds" %
+                         (i + 1, drift))
+            # Fail if necessary
+            if drift > drift_threshold_single:
+                raise error.TestFail("Time drift too large at iteration %d: "
+                                     "%.2f seconds" % (i + 1, drift))
+
+        # Get final time
+        (ht1, gt1) = kvm_test_utils.get_time(session, time_command,
+                                             time_filter_re, time_format)
+
+    finally:
+        if session:
+            session.close()
+
+    # Report results
+    host_delta = ht1 - ht0
+    guest_delta = gt1 - gt0
+    drift = abs(host_delta - guest_delta)
+    logging.info("Host duration (%d stops): %.2f" %
+                 (stop_iterations, host_delta))
+    logging.info("Guest duration (%d stops): %.2f" %
+                 (stop_iterations, guest_delta))
+    logging.info("Drift after %d stops: %.2f seconds" %
+                 (stop_iterations, drift))
+
+    # Fail if necessary
+    if drift > drift_threshold:
+        raise error.TestFail("Time drift too large after %d stops: "
+                             "%.2f seconds" % (stop_iterations, drift))
diff --git a/client/tests/kvm/tests_base.cfg.sample b/client/tests/kvm/tests_base.cfg.sample
index 5349034..c2babb9 100644
--- a/client/tests/kvm/tests_base.cfg.sample
+++ b/client/tests/kvm/tests_base.cfg.sample
@@ -183,6 +183,13 @@ variants:
                 reboot_iterations = 1
                 drift_threshold = 10
                 drift_threshold_single = 3
+            - with_stop:
+                type = timedrift_with_stop
+                stop_interations = 1
+                drift_threshold = 10
+                drift_threshold_single = 3
+
+
 
     - balloon_check:  install setup unattended_install
         type = balloon_check