Re: [Qemu-devel] [PATCH v6 39/42] iotests: Add filter commit test cases

[Vladimir Sementsov-Ogievskiy]

09.08.2019 19:14, Max Reitz wrote:
> This patch adds some tests on how commit copes with filter nodes.
> 
> Signed-off-by: Max Reitz <address@hidden>
> ---
>   tests/qemu-iotests/040     | 177 +++++++++++++++++++++++++++++++++++++
>   tests/qemu-iotests/040.out |   4 +-
>   2 files changed, 179 insertions(+), 2 deletions(-)
> 
> diff --git a/tests/qemu-iotests/040 b/tests/qemu-iotests/040
> index 6db9abf8e6..a0a0db8889 100755
> --- a/tests/qemu-iotests/040
> +++ b/tests/qemu-iotests/040
> @@ -428,5 +428,182 @@ class TestReopenOverlay(ImageCommitTestCase):
>       def test_reopen_overlay(self):
>           self.run_commit_test(self.img1, self.img0)
>   
> +class TestCommitWithFilters(iotests.QMPTestCase):
> +    img0 = os.path.join(iotests.test_dir, '0.img')
> +    img1 = os.path.join(iotests.test_dir, '1.img')
> +    img2 = os.path.join(iotests.test_dir, '2.img')
> +    img3 = os.path.join(iotests.test_dir, '3.img')
> +
> +    def setUp(self):
> +        qemu_img('create', '-f', iotests.imgfmt, self.img0, '64M')
> +        qemu_img('create', '-f', iotests.imgfmt, self.img1, '64M')
> +        qemu_img('create', '-f', iotests.imgfmt, self.img2, '64M')
> +        qemu_img('create', '-f', iotests.imgfmt, self.img3, '64M')
> +
> +        qemu_io('-f', iotests.imgfmt, '-c', 'write -P 1 0M 1M', self.img0)
> +        qemu_io('-f', iotests.imgfmt, '-c', 'write -P 2 1M 1M', self.img1)
> +        qemu_io('-f', iotests.imgfmt, '-c', 'write -P 3 2M 1M', self.img2)
> +        qemu_io('-f', iotests.imgfmt, '-c', 'write -P 4 3M 1M', self.img3)
> +
> +        # Distributions of the patterns in the files; this is checked
> +        # by tearDown() and should be changed by the test cases as is
> +        # necessary
> +        self.pattern_files = [self.img0, self.img1, self.img2, self.img3]
> +
> +        self.vm = iotests.VM()
> +        self.vm.launch()
> +        self.has_quit = False
> +
> +        result = self.vm.qmp('object-add', qom_type='throttle-group', 
> id='tg')
> +        self.assert_qmp(result, 'return', {})
> +
> +        result = self.vm.qmp('blockdev-add', **{
> +                'node-name': 'top-filter',
> +                'driver': 'throttle',
> +                'throttle-group': 'tg',
> +                'file': {
> +                    'node-name': 'cow-3',
> +                    'driver': iotests.imgfmt,
> +                    'file': {
> +                        'driver': 'file',
> +                        'filename': self.img3
> +                    },
> +                    'backing': {
> +                        'node-name': 'cow-2',
> +                        'driver': iotests.imgfmt,
> +                        'file': {
> +                            'driver': 'file',
> +                            'filename': self.img2
> +                        },
> +                        'backing': {
> +                            'node-name': 'cow-1',
> +                            'driver': iotests.imgfmt,
> +                            'file': {
> +                                'driver': 'file',
> +                                'filename': self.img1
> +                            },
> +                            'backing': {
> +                                'node-name': 'bottom-filter',
> +                                'driver': 'throttle',
> +                                'throttle-group': 'tg',
> +                                'file': {
> +                                    'node-name': 'cow-0',
> +                                    'driver': iotests.imgfmt,
> +                                    'file': {
> +                                        'driver': 'file',
> +                                        'filename': self.img0
> +                                    }
> +                                }
> +                            }
> +                        }
> +                    }
> +                }
> +            })
> +        self.assert_qmp(result, 'return', {})
> +
> +    def tearDown(self):
> +        self.vm.shutdown(has_quit=self.has_quit)
> +
> +        for index in range(len(self.pattern_files)):

you may use enumerate for such cases:
for ind, file in enumerate(self.pattern_files):
    ...

> +            result = qemu_io('-f', iotests.imgfmt,
> +                             '-c', 'read -P %i %iM 1M' % (index + 1, index),
> +                             self.pattern_files[index])
> +            self.assertFalse('Pattern verification failed' in result)

A bit better would be to keep this loop in a function and do "writes" through 
it too,
to make it more obvious that they are the same.. But I'm OK with it as is.

> +
> +        os.remove(self.img3)
> +        os.remove(self.img2)
> +        os.remove(self.img1)
> +        os.remove(self.img0)
> +
> +    # Filters make for funny filenames, so we cannot just use
> +    # self.imgX to get them
> +    def get_filename(self, node):
> +        return self.vm.node_info(node)['image']['filename']
> +

maybe:
def assertHasNode(self, node_name):
   self.assertIsNotNone(self.vm.node_info(node_name))

and similar for assertNoNode...

> +    def test_filterless_commit(self):
> +        self.assert_no_active_block_jobs()

why not just to include this call into setUp() ? Or even, just drop it?
We create and start new vm in setUp, it don't have any block jobs for sure.

> +        result = self.vm.qmp('block-commit',
> +                             job_id='commit',
> +                             device='top-filter',
> +                             top_node='cow-2',
> +                             base_node='cow-1')
> +        self.assert_qmp(result, 'return', {})
> +        self.wait_until_completed(drive='commit')
> +
> +        self.assertIsNotNone(self.vm.node_info('cow-3'))
> +        self.assertIsNone(self.vm.node_info('cow-2'))
> +        self.assertIsNotNone(self.vm.node_info('cow-1'))
> +
> +        # 2 has been comitted into 1
> +        self.pattern_files[2] = self.img1
> +
> +    def test_commit_through_filter(self):
> +        self.assert_no_active_block_jobs()
> +        result = self.vm.qmp('block-commit',
> +                             job_id='commit',
> +                             device='top-filter',
> +                             top_node='cow-1',
> +                             base_node='cow-0')
> +        self.assert_qmp(result, 'return', {})
> +        self.wait_until_completed(drive='commit')
> +
> +        self.assertIsNotNone(self.vm.node_info('cow-2'))
> +        self.assertIsNone(self.vm.node_info('cow-1'))
> +        self.assertIsNone(self.vm.node_info('bottom-filter'))
> +        self.assertIsNotNone(self.vm.node_info('cow-0'))
> +
> +        # 1 has been comitted into 0
> +        self.pattern_files[1] = self.img0
> +
> +    def test_filtered_active_commit_with_filter(self):
> +        # Add a device, so the commit job finds a parent it can change
> +        # to point to the base node (so we can test that top-filter is
> +        # dropped from the graph)
> +        result = self.vm.qmp('device_add', id='drv0', driver='virtio-blk',
> +                             drive='top-filter')
> +        self.assert_qmp(result, 'return', {})
> +
> +        # Try to release our reference to top-filter; that should not
> +        # work because drv0 uses it
> +        result = self.vm.qmp('blockdev-del', node_name='top-filter')
> +        self.assert_qmp(result, 'error/class', 'GenericError')
> +        self.assert_qmp(result, 'error/desc', 'Node top-filter is in use')
> +
> +        self.assert_no_active_block_jobs()
> +        result = self.vm.qmp('block-commit',
> +                             job_id='commit',
> +                             device='top-filter',
> +                             base_node='cow-2')
> +        self.assert_qmp(result, 'return', {})
> +        self.complete_and_wait(drive='commit')
> +
> +        # Try to release our reference to top-filter again
> +        result = self.vm.qmp('blockdev-del', node_name='top-filter')
> +        self.assert_qmp(result, 'return', {})
> +
> +        self.assertIsNone(self.vm.node_info('top-filter'))
> +        self.assertIsNone(self.vm.node_info('cow-3'))
> +        self.assertIsNotNone(self.vm.node_info('cow-2'))

It would be good to assert here the cow-2 became drv0 child. However, otherwise
it should be automatically dropped, so it's not necessary.

> +
> +        # 3 has been comitted into 2
> +        self.pattern_files[3] = self.img2
> +
> +    def test_filtered_active_commit_without_filter(self):
> +        self.assert_no_active_block_jobs()
> +        result = self.vm.qmp('block-commit',
> +                             job_id='commit',
> +                             device='top-filter',
> +                             top_node='cow-3',
> +                             base_node='cow-2')
> +        self.assert_qmp(result, 'return', {})

can we check that really "active" commit is started, i.e. mirror block job?

> +        self.complete_and_wait(drive='commit')
> +
> +        self.assertIsNotNone(self.vm.node_info('top-filter'))
> +        self.assertIsNone(self.vm.node_info('cow-3'))
> +        self.assertIsNotNone(self.vm.node_info('cow-2'))
> +
> +        # 3 has been comitted into 2
> +        self.pattern_files[3] = self.img2
> +
>   if __name__ == '__main__':
>       iotests.main(supported_fmts=['qcow2', 'qed'])
> diff --git a/tests/qemu-iotests/040.out b/tests/qemu-iotests/040.out
> index 220a5fa82c..fe58934d7a 100644
> --- a/tests/qemu-iotests/040.out
> +++ b/tests/qemu-iotests/040.out
> @@ -1,5 +1,5 @@
> -...............................................
> +...................................................
>   ----------------------------------------------------------------------
> -Ran 47 tests
> +Ran 51 tests
>   
>   OK
> 

With or without any of my suggestions:
Reviewed-by: Vladimir Sementsov-Ogievskiy <address@hidden>

-- 
Best regards,
Vladimir