qemu.tests: Bug fix about drift for timedrift_with_stop

kvm guests CLOCK_MONOTONIC not count when guest is paused,
so drift need to subtract stop_time.

starting from Win2012 Windows no longer relies on number of
injected RTC interrupts for time keeping, and the time drift
is seen because "stop" monitor command also stops PM timer,
so this is unsupported scenario from Win2012 and disabled this
case from Win2012.

changes from v1:
    add some comments for windows guest.
changes from v2:
    add check rtc_clock for windows
changes from v3:
    add new scenario rtc_clock = host and rtc_clock = vm for this case.
Signed-off-by: NShuping Cui <scui@redhat.com>

qemu/tests/timedrift_with_stop.py

@@ -43,6 +43,7 @@ def run(test, params, env):
     time_filter_re = params["time_filter_re"]
     # Time format for time.strptime()
     time_format = params["time_format"]
+    rtc_clock = params.get("rtc_clock", "host")
     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))
@@ -88,6 +89,12 @@ def run(test, params, env):
             host_delta = ht1_ - ht0_
             guest_delta = gt1_ - gt0_
             drift = abs(host_delta - guest_delta)
+            # kvm guests CLOCK_MONOTONIC not count when guest is paused,
+            # so drift need to subtract stop_time.
+            if not stop_with_signal:
+                drift = abs(drift - stop_time)
+                if params.get("os_type") == "windows" and rtc_clock == "host":
+                    drift = abs(host_delta - guest_delta)
             logging.info("Host duration (iteration %d): %.2f",
                          (i + 1), host_delta)
             logging.info("Guest duration (iteration %d): %.2f",
@@ -116,6 +123,12 @@ def run(test, params, env):
     host_delta = ht1 - ht0
     guest_delta = gt1 - gt0
     drift = abs(host_delta - guest_delta)
+    # kvm guests CLOCK_MONOTONIC not count when guest is paused,
+    # so drift need to subtract stop_time.
+    if not stop_with_signal:
+        drift = abs(drift - stop_time)
+        if params.get("os_type") == "windows" and rtc_clock == "host":
+            drift = abs(host_delta - guest_delta)
     logging.info("Host duration (%d stops): %.2f",
                  stop_iterations, host_delta)
     logging.info("Guest duration (%d stops): %.2f",

tests/cfg/timedrift.cfg

@@ -35,10 +35,21 @@
                     drift_threshold = 10
                     drift_threshold_single = 3
                 - with_stop:
+                    # starting from Win2012 Windows no longer relies on number of injected RTC interrupts for time keeping,
+                    # and the time drift is seen because "stop" monitor command also stops PM timer,
+                    # so this is unsupported scenario from Win2012.
+                    Windows:
+                        only Win2000, WinXP, Win2003, WinVista, Win7, Win2008
                     type = timedrift_with_stop
                     stop_interations = 1
+                    stop_time = 60
                     drift_threshold = 10
                     drift_threshold_single = 3
+                    variants:
+                        - clock_host:
+                            rtc_clock = host
+                        - clock_vm:
+                            rtc_clock = vm
             variants:
                 - ntp:
                     no JeOS
@@ -66,11 +77,23 @@
             test_duration = 600
             smp_min =2
         - with_signal_stop:
-            no RHEL.3.9
-            no RHEL.4
+            # starting from Win2012 Windows no longer relies on number of injected RTC interrupts for time keeping,
+            # and the time drift is seen because "stop" monitor command also stops PM timer,
+            # so this is unsupported scenario from Win2012.
+            Windows:
+                only Win2000, WinXP, Win2003, WinVista, Win7, Win2008
+            no RHEL.3.9, RHEL.4
             type = timedrift_with_stop
             stop_interations = 1
             stop_with_signal = yes
+            stop_time = 60
+            drift_threshold = 10
+            drift_threshold_single = 3
+            variants:
+                - clock_host:
+                    rtc_clock = host
+                - clock_vm:
+                    rtc_clock = vm
     variants:
         - no_pvclock:
             no RHEL.5