[PULL 06/24] qemu-iotests/199: change discard patterns

[Eric Blake <eblake@redhat.com>]

From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

iotest 199 works too long because of many discard operations. At the
same time, postcopy period is very short, in spite of all these
efforts.

So, let's use less discards (and with more interesting patterns) to
reduce test timing. In the next commit we'll increase postcopy period.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
Tested-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200727194236.19551-6-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
---
 tests/qemu-iotests/199 | 44 +++++++++++++++++++++++++-----------------
 1 file changed, 26 insertions(+), 18 deletions(-)

diff --git a/tests/qemu-iotests/199 b/tests/qemu-iotests/199
index 190e820b8408..da4dae01fb5d 100755
--- a/tests/qemu-iotests/199
+++ b/tests/qemu-iotests/199
@@ -30,6 +30,28 @@ size = '256G'
 fifo = os.path.join(iotests.test_dir, 'mig_fifo')


+GiB = 1024 * 1024 * 1024
+
+discards1 = (
+    (0, GiB),
+    (2 * GiB + 512 * 5, 512),
+    (3 * GiB + 512 * 5, 512),
+    (100 * GiB, GiB)
+)
+
+discards2 = (
+    (3 * GiB + 512 * 8, 512),
+    (4 * GiB + 512 * 8, 512),
+    (50 * GiB, GiB),
+    (100 * GiB + GiB // 2, GiB)
+)
+
+
+def apply_discards(vm, discards):
+    for d in discards:
+        vm.hmp_qemu_io('drive0', 'discard {} {}'.format(*d))
+
+
 def event_seconds(event):
     return event['timestamp']['seconds'] + \
         event['timestamp']['microseconds'] / 1000000.0
@@ -80,9 +102,7 @@ class TestDirtyBitmapPostcopyMigration(iotests.QMPTestCase):
         self.vm_b_events = []

     def test_postcopy(self):
-        discard_size = 0x40000000
         granularity = 512
-        chunk = 4096

         result = self.vm_a.qmp('block-dirty-bitmap-add', node='drive0',
                                name='bitmap', granularity=granularity)
@@ -92,14 +112,7 @@ class TestDirtyBitmapPostcopyMigration(iotests.QMPTestCase):
                                node='drive0', name='bitmap')
         empty_sha256 = result['return']['sha256']

-        s = 0
-        while s < discard_size:
-            self.vm_a.hmp_qemu_io('drive0', 'discard %d %d' % (s, chunk))
-            s += 0x10000
-        s = 0x8000
-        while s < discard_size:
-            self.vm_a.hmp_qemu_io('drive0', 'discard %d %d' % (s, chunk))
-            s += 0x10000
+        apply_discards(self.vm_a, discards1 + discards2)

         result = self.vm_a.qmp('x-debug-block-dirty-bitmap-sha256',
                                node='drive0', name='bitmap')
@@ -111,10 +124,8 @@ class TestDirtyBitmapPostcopyMigration(iotests.QMPTestCase):
         result = self.vm_a.qmp('block-dirty-bitmap-clear', node='drive0',
                                name='bitmap')
         self.assert_qmp(result, 'return', {})
-        s = 0
-        while s < discard_size:
-            self.vm_a.hmp_qemu_io('drive0', 'discard %d %d' % (s, chunk))
-            s += 0x10000
+
+        apply_discards(self.vm_a, discards1)

         caps = [{'capability': 'dirty-bitmaps', 'state': True},
                 {'capability': 'events', 'state': True}]
@@ -134,10 +145,7 @@ class TestDirtyBitmapPostcopyMigration(iotests.QMPTestCase):
         event_resume = self.vm_b.event_wait('RESUME')
         self.vm_b_events.append(event_resume)

-        s = 0x8000
-        while s < discard_size:
-            self.vm_b.hmp_qemu_io('drive0', 'discard %d %d' % (s, chunk))
-            s += 0x10000
+        apply_discards(self.vm_b, discards2)

         match = {'data': {'status': 'completed'}}
         event_complete = self.vm_b.event_wait('MIGRATION', match=match)
-- 
2.27.0