qemu-iotests/199: increase postcopy period

The test wants to force a bitmap postcopy. Still, the resulting
postcopy period is very small. Let's increase it by adding more
bitmaps to migrate. Also, test disabled bitmaps migration.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: NAndrey Shinkevich <andrey.shinkevich@virtuozzo.com>
Tested-by: NEric Blake <eblake@redhat.com>
Message-Id: <20200727194236.19551-7-vsementsov@virtuozzo.com>
Signed-off-by: NEric Blake <eblake@redhat.com>

tests/qemu-iotests/199

@@ -103,29 +103,45 @@ class TestDirtyBitmapPostcopyMigration(iotests.QMPTestCase):
 
     def test_postcopy(self):
         granularity = 512
+        nb_bitmaps = 15
 
-        result = self.vm_a.qmp('block-dirty-bitmap-add', node='drive0',
-                               name='bitmap', granularity=granularity)
-        self.assert_qmp(result, 'return', {})
+        for i in range(nb_bitmaps):
+            result = self.vm_a.qmp('block-dirty-bitmap-add', node='drive0',
+                                   name='bitmap{}'.format(i),
+                                   granularity=granularity)
+            self.assert_qmp(result, 'return', {})
 
         result = self.vm_a.qmp('x-debug-block-dirty-bitmap-sha256',
-                               node='drive0', name='bitmap')
+                               node='drive0', name='bitmap0')
         empty_sha256 = result['return']['sha256']
 
-        apply_discards(self.vm_a, discards1 + discards2)
+        apply_discards(self.vm_a, discards1)
 
         result = self.vm_a.qmp('x-debug-block-dirty-bitmap-sha256',
-                               node='drive0', name='bitmap')
-        sha256 = result['return']['sha256']
+                               node='drive0', name='bitmap0')
+        discards1_sha256 = result['return']['sha256']
 
         # Check, that updating the bitmap by discards works
-        assert sha256 != empty_sha256
+        assert discards1_sha256 != empty_sha256
 
-        result = self.vm_a.qmp('block-dirty-bitmap-clear', node='drive0',
-                               name='bitmap')
-        self.assert_qmp(result, 'return', {})
+        # We want to calculate resulting sha256. Do it in bitmap0, so, disable
+        # other bitmaps
+        for i in range(1, nb_bitmaps):
+            result = self.vm_a.qmp('block-dirty-bitmap-disable', node='drive0',
+                                   name='bitmap{}'.format(i))
+            self.assert_qmp(result, 'return', {})
 
-        apply_discards(self.vm_a, discards1)
+        apply_discards(self.vm_a, discards2)
+
+        result = self.vm_a.qmp('x-debug-block-dirty-bitmap-sha256',
+                               node='drive0', name='bitmap0')
+        all_discards_sha256 = result['return']['sha256']
+
+        # Now, enable some bitmaps, to be updated during migration
+        for i in range(2, nb_bitmaps, 2):
+            result = self.vm_a.qmp('block-dirty-bitmap-enable', node='drive0',
+                                   name='bitmap{}'.format(i))
+            self.assert_qmp(result, 'return', {})
 
         caps = [{'capability': 'dirty-bitmaps', 'state': True},
                 {'capability': 'events', 'state': True}]
@@ -145,6 +161,7 @@ class TestDirtyBitmapPostcopyMigration(iotests.QMPTestCase):
         event_resume = self.vm_b.event_wait('RESUME')
         self.vm_b_events.append(event_resume)
 
+        # enabled bitmaps should be updated
         apply_discards(self.vm_b, discards2)
 
         match = {'data': {'status': 'completed'}}
@@ -158,7 +175,7 @@ class TestDirtyBitmapPostcopyMigration(iotests.QMPTestCase):
         downtime = event_dist(event_stop, event_resume)
         postcopy_time = event_dist(event_resume, event_complete)
 
-        # TODO: assert downtime * 10 < postcopy_time
+        assert downtime * 10 < postcopy_time
         if debug:
             print('downtime:', downtime)
             print('postcopy_time:', postcopy_time)
@@ -166,12 +183,15 @@ class TestDirtyBitmapPostcopyMigration(iotests.QMPTestCase):
         # Assert that bitmap migration is finished (check that successor bitmap
         # is removed)
         result = self.vm_b.qmp('query-block')
-        assert len(result['return'][0]['dirty-bitmaps']) == 1
-
-        # Check content of migrated (and updated by new writes) bitmap
-        result = self.vm_b.qmp('x-debug-block-dirty-bitmap-sha256',
-                               node='drive0', name='bitmap')
-        self.assert_qmp(result, 'return/sha256', sha256)
+        assert len(result['return'][0]['dirty-bitmaps']) == nb_bitmaps
+
+        # Check content of migrated bitmaps. Still, don't waste time checking
+        # every bitmap
+        for i in range(0, nb_bitmaps, 5):
+            result = self.vm_b.qmp('x-debug-block-dirty-bitmap-sha256',
+                                   node='drive0', name='bitmap{}'.format(i))
+            sha256 = discards1_sha256 if i % 2 else all_discards_sha256
+            self.assert_qmp(result, 'return/sha256', sha256)
 
 
 if __name__ == '__main__':