Re: [Qemu-devel] [PATCH RFC v3 13/14] iotests: add dirty bitmap migration test

[John Snow <jsnow@redhat.com>]

On 02/18/2015 09:00 AM, Vladimir Sementsov-Ogievskiy wrote:
> [the same test as 117, but not using qmp: query-block-dirty-bitmap.
> only one test from {117, 118} will be in the next patch set version]
>
> The test starts two vms (vm_a, vm_b), create dirty bitmap in
> the first one, do several writes to corresponding device and
> then migrate vm_a to vm_b with dirty bitmaps.
>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@parallels.com>
> ---
>   tests/qemu-iotests/118     | 87 ++++++++++++++++++++++++++++++++++++++++++++++
>   tests/qemu-iotests/118.out |  5 +++
>   tests/qemu-iotests/group   |  1 +
>   3 files changed, 93 insertions(+)
>   create mode 100755 tests/qemu-iotests/118
>   create mode 100644 tests/qemu-iotests/118.out
>
> diff --git a/tests/qemu-iotests/118 b/tests/qemu-iotests/118
> new file mode 100755
> index 0000000..a85ea56
> --- /dev/null
> +++ b/tests/qemu-iotests/118
> @@ -0,0 +1,87 @@
> +#!/usr/bin/env python
> +#
> +# Tests for dirty bitmaps migration.
> +#
> +# (C) Vladimir Sementsov-Ogievskiy 2015
> +#
> +# This program is free software; you can redistribute it and/or modify
> +# it under the terms of the GNU General Public License as published by
> +# the Free Software Foundation; either version 2 of the License, or
> +# (at your option) any later version.
> +#
> +# This program is distributed in the hope that it will be useful,
> +# but WITHOUT ANY WARRANTY; without even the implied warranty of
> +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> +# GNU General Public License for more details.
> +#
> +# You should have received a copy of the GNU General Public License
> +# along with this program.  If not, see <http://www.gnu.org/licenses/>.
> +#
> +
> +import os
> +import iotests
> +import time
> +from iotests import qemu_img
> +
> +disk_a = os.path.join(iotests.test_dir, 'disk_a')
> +disk_b = os.path.join(iotests.test_dir, 'disk_b')
> +fifo   = os.path.join(iotests.test_dir, 'fifo')
> +
> +size   = 0x40000000 # 1G
> +sector_size = 512
> +granularity = 0x10000
> +regions = [
> +    { 'start': 0,          'count': 0x100000 },
> +    { 'start': 0x10000000, 'count': 0x20000  },
> +    { 'start': 0x39990000, 'count': 0x10000  }
> +    ]
> +
> +regions_in_sectors = [
> +    { key: val / sector_size for (key, val) in el.items() } for el in regions]
> +

Not used in this test.

> +class TestDirtyBitmapMigration(iotests.QMPTestCase):
> +
> +    def setUp(self):
> +        os.mkfifo(fifo)
> +        qemu_img('create', '-f', iotests.imgfmt, disk_a, str(size))
> +        qemu_img('create', '-f', iotests.imgfmt, disk_b, str(size))
> +        self.vm_a = iotests.VM().add_drive(disk_a)
> +        self.vm_b = iotests.VM().add_drive(disk_b)
> +        self.vm_b.add_incoming_migration("exec: cat " + fifo)
> +        self.vm_a.launch()
> +        self.vm_b.launch()
> +
> +    def tearDown(self):
> +        self.vm_a.shutdown()
> +        self.vm_b.shutdown()
> +        os.remove(disk_a)
> +        os.remove(disk_b)
> +        os.remove(fifo)
> +
> +    def test_migration(self):
> +        result = self.vm_a.qmp('block-dirty-bitmap-add', node='drive0',
> +                               name='bitmap', granularity=granularity)
> +        self.assert_qmp(result, 'return', {});
> +
> +        for r in regions:
> +          self.vm_a.hmp_qemu_io('drive0',
> +                                'write %d %d' % (r['start'], r['count']))
> +
> +        result = self.vm_a.qmp('query-block');
> +        md5 = result['return'][0]['dirty-bitmaps'][0]['md5']
> +
> +        result = self.vm_a.qmp('migrate-set-capabilities',
> +                               capabilities=[{'capability': 'dirty-bitmaps',
> +                                              'state': True}])
> +        self.assert_qmp(result, 'return', {})
> +
> +        result = self.vm_a.qmp('migrate', uri='exec:cat>' + fifo)
> +        while self.vm_a.qmp('query-migrate')['return']['status'] != 'completed':
> +          time.sleep(1)
> +

Might be possible to wait on a status completion here. Adding a method 
to VM:

def event_wait(self, name='BLOCK_JOB_COMPLETED', maxwait=10):
     for _ in range(maxwait):
         for event in self.get_qmp_events(wait=True):
             if event['event'] == name:
                 return event
     return None


And replacing the sleep and poll loop with:

result = self.vm_a.qmp('migrate', uri='exec:cat>' + fifo)
self.assertIsNotNone(self.vm_a.event_wait("STOP"))
self.assertIsNotNone(self.vm_b.event_wait("RESUME"))

works just as well without the poll/sleep.

> +        result = self.vm_b.qmp('query-block');
> +        self.assert_qmp(result, 'return[0]/dirty-bitmaps[0]/md5', md5);
> +
> +
> +if __name__ == '__main__':
> +    iotests.main()
> diff --git a/tests/qemu-iotests/118.out b/tests/qemu-iotests/118.out
> new file mode 100644
> index 0000000..ae1213e
> --- /dev/null
> +++ b/tests/qemu-iotests/118.out
> @@ -0,0 +1,5 @@
> +.
> +----------------------------------------------------------------------
> +Ran 1 tests
> +
> +OK
> diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group
> index 6ad5b55..1fd1983 100644
> --- a/tests/qemu-iotests/group
> +++ b/tests/qemu-iotests/group
> @@ -119,3 +119,4 @@
>   114 rw auto quick
>   116 rw auto quick
>   117 rw auto quick
> +118 rw auto quick
>

Thanks,
--js