Re: [Qemu-devel] [PATCH v10 11/12] iotests: add dirty bitmap migration test

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Vladimir Sementsov-Ogievskiy (vsementsov@virtuozzo.com) wrote:
> 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.

> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
>  tests/qemu-iotests/169     | 141 +++++++++++++++++++++++++++++++++++++++++++++
>  tests/qemu-iotests/169.out |   5 ++
>  tests/qemu-iotests/group   |   1 +
>  3 files changed, 147 insertions(+)
>  create mode 100755 tests/qemu-iotests/169
>  create mode 100644 tests/qemu-iotests/169.out
> 
> diff --git a/tests/qemu-iotests/169 b/tests/qemu-iotests/169
> new file mode 100755
> index 0000000000..8801f73b10
> --- /dev/null
> +++ b/tests/qemu-iotests/169
> @@ -0,0 +1,141 @@
> +#!/usr/bin/env python
> +#
> +# Tests for dirty bitmaps migration.
> +#
> +# Copyright (c) 2016-2017 Virtuozzo International GmbH. All rights reserved.
> +#
> +# 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
> +import itertools
> +import operator
> +import new
> +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')
> +size = '1M'
> +mig_file = os.path.join(iotests.test_dir, 'mig_file')
> +
> +
> +class TestDirtyBitmapMigration(iotests.QMPTestCase):
> +    def tearDown(self):
> +        self.vm_a.shutdown()
> +        self.vm_b.shutdown()
> +        os.remove(disk_a)
> +        os.remove(disk_b)
> +        os.remove(mig_file)
> +
> +    def setUp(self):
> +        qemu_img('create', '-f', iotests.imgfmt, disk_a, size)
> +        qemu_img('create', '-f', iotests.imgfmt, disk_b, size)
> +
> +        self.vm_a = iotests.VM(path_suffix='a').add_drive(disk_a)
> +        self.vm_a.launch()
> +
> +        self.vm_b = iotests.VM(path_suffix='b')
> +        self.vm_b.add_incoming("exec: cat '" + mig_file + "'")
> +
> +    def add_bitmap(self, vm, granularity, persistent):
> +        params = {'node': 'drive0',
> +                  'name': 'bitmap0',
> +                  'granularity': granularity}
> +        if persistent:
> +            params['persistent'] = True
> +            params['autoload'] = True
> +
> +        result = vm.qmp('block-dirty-bitmap-add', **params)
> +        self.assert_qmp(result, 'return', {});
> +
> +    def get_bitmap_hash(self, vm):
> +        result = vm.qmp('x-debug-block-dirty-bitmap-sha256',
> +                        node='drive0', name='bitmap0')
> +        return result['return']['sha256']
> +
> +    def check_bitmap(self, vm, sha256):
> +        result = vm.qmp('x-debug-block-dirty-bitmap-sha256',
> +                        node='drive0', name='bitmap0')
> +        if sha256:
> +            self.assert_qmp(result, 'return/sha256', sha256);
> +        else:
> +            self.assert_qmp(result, 'error/desc',
> +                            "Dirty bitmap 'bitmap0' not found");
> +
> +    def do_test_migration(self, persistent, migrate_bitmaps, online,
> +                          shared_storage):
> +        granularity = 512
> +
> +        # regions = ((start, count), ...)
> +        regions = ((0, 0x10000),
> +                   (0xf0000, 0x10000),
> +                   (0xa0201, 0x1000))
> +
> +        should_migrate = migrate_bitmaps or persistent and shared_storage
> +
> +        self.vm_b.add_drive(disk_a if shared_storage else disk_b)
> +
> +        if online:
> +            os.mkfifo(mig_file)
> +            self.vm_b.launch()
> +
> +        self.add_bitmap(self.vm_a, granularity, persistent)
> +        for r in regions:
> +            self.vm_a.hmp_qemu_io('drive0', 'write %d %d' % r)
> +        sha256 = self.get_bitmap_hash(self.vm_a)
> +
> +        if migrate_bitmaps:
> +            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>' + mig_file)
> +        self.vm_a.event_wait("STOP")

Stefan recently fixed a similar case in another test; 'STOP' is not
sufficient to know migration has finished, just that it's in the last
stage.   The trick is to use the new migration events and wait for the
finish in there.

Other than that I'm not really a python person, but it looks OK fromt he
migration side of it.

Dave

> +        if not online:
> +            self.vm_a.shutdown()
> +            self.vm_b.launch()
> +
> +        self.vm_b.event_wait("RESUME", timeout=10.0)
> +
> +        self.check_bitmap(self.vm_b, sha256 if should_migrate else False)
> +
> +        if should_migrate:
> +            self.vm_b.shutdown()
> +            self.vm_b.launch()
> +            self.check_bitmap(self.vm_b, sha256 if persistent else False)
> +
> +
> +def inject_test_case(klass, name, method, *args, **kwargs):
> +    mc = operator.methodcaller(method, *args, **kwargs)
> +    setattr(klass, 'test_' + name, new.instancemethod(mc, None, klass))
> +
> +for cmb in list(itertools.product((True, False), repeat=3)):
> +    name = ('_' if cmb[0] else '_not_') + 'persistent_'
> +    name += ('_' if cmb[1] else '_not_') + 'migbitmap_'
> +    name += '_online' if cmb[2] else '_offline'
> +
> +    # TODO fix shared-storage bitmap migration and enable cases for it
> +    args = list(cmb) + [False]
> +
> +    inject_test_case(TestDirtyBitmapMigration, name, 'do_test_migration',
> +                     *args)
> +
> +
> +if __name__ == '__main__':
> +    iotests.main(supported_fmts=['qcow2'])
> diff --git a/tests/qemu-iotests/169.out b/tests/qemu-iotests/169.out
> new file mode 100644
> index 0000000000..594c16f49f
> --- /dev/null
> +++ b/tests/qemu-iotests/169.out
> @@ -0,0 +1,5 @@
> +........
> +----------------------------------------------------------------------
> +Ran 8 tests
> +
> +OK
> diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group
> index a2dfe79d86..498c52c4c1 100644
> --- a/tests/qemu-iotests/group
> +++ b/tests/qemu-iotests/group
> @@ -169,6 +169,7 @@
>  162 auto quick
>  163 rw auto quick
>  165 rw auto quick
> +169 rw auto quick
>  170 rw auto quick
>  171 rw auto quick
>  172 auto
> -- 
> 2.11.1
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK