tests/vm: Display remaining seconds to wait for a VM to start

Signed-off-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20181013004034.6968-5-f4bug@amsat.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NFam Zheng <famz@redhat.com>

tests/vm/basevm.py

@@ -177,11 +177,14 @@ class BaseVM(object):
 
     def wait_ssh(self, seconds=300):
         starttime = datetime.datetime.now()
+        endtime = starttime + datetime.timedelta(seconds=seconds)
         guest_up = False
-        while (datetime.datetime.now() - starttime).total_seconds() < seconds:
+        while datetime.datetime.now() < endtime:
             if self.ssh("exit 0") == 0:
                 guest_up = True
                 break
+            seconds = (endtime - datetime.datetime.now()).total_seconds()
+            logging.debug("%ds before timeout", seconds)
             time.sleep(1)
         if not guest_up:
             raise Exception("Timeout while waiting for guest ssh")