Re: [Qemu-devel] [PATCH v12 17/17] iotests: add incremental backup failure recovery test

[Max Reitz <mreitz@redhat.com>]

On 2015-02-11 at 17:08, John Snow wrote:
>
>
> On 02/11/2015 05:01 PM, Max Reitz wrote:
>> On 2015-02-09 at 20:35, John Snow wrote:
>>> To test the failure case, we modify iotests.py to allow us to specify
>>> that we'd like to allow failures when we wait for block job events.
>>>
>>> Signed-off-by: John Snow <jsnow@redhat.com>
>>> ---
>>>   tests/qemu-iotests/112        | 55
>>> ++++++++++++++++++++++++++++++++++++++++++-
>>>   tests/qemu-iotests/112.out    |  4 ++--
>>>   tests/qemu-iotests/iotests.py |  6 +++--
>>>   3 files changed, 60 insertions(+), 5 deletions(-)
>>>
>>> diff --git a/tests/qemu-iotests/112 b/tests/qemu-iotests/112
>>> index 7d1a6ec..0c1d35a 100644
>>> --- a/tests/qemu-iotests/112
>>> +++ b/tests/qemu-iotests/112
>>> @@ -24,6 +24,11 @@ import os
>>>   import iotests
>>>   from iotests import qemu_img, qemu_io, create_image
>>> +def blkdebug_rule(file, type, **kwargs):
>>> +    file.write('[%s]\n' % type)
>>> +    for key, value in kwargs.iteritems():
>>> +        file.write('%s = "%s"\n' % (key, value))
>>> +    file.write('\n')
>>>   def io_write_patterns(img, patterns):
>>>       for pattern in patterns:
>>> @@ -136,7 +141,11 @@ class TestIncrementalBackup(iotests.QMPTestCase):
>>>                                mode='existing')
>>>           self.assert_qmp(result, 'return', {})
>>> -        event = self.wait_until_completed(bitmap.node,
>>> check_offset=validate)
>>> +        event = self.wait_until_completed(bitmap.node,
>>> check_offset=validate,
>>> +                                          allow_failures=(not 
>>> validate))
>>> +        if 'error' in event['data']:
>>> +            bitmap.del_target()
>>> +            return False
>>>           if validate:
>>>               return self.check_incremental(target)
>>> @@ -221,6 +230,50 @@ class TestIncrementalBackup(iotests.QMPTestCase):
>>>           self.assertTrue(res1 and res2)
>>> +    def test_incremental_failure(self):
>>> +        blkdebug = os.path.join(iotests.test_dir, 'blkdebug.conf')
>>> +        self.files.append(blkdebug)
>>> +
>>> +        with open(blkdebug, 'w+') as file:
>>> +            blkdebug_rule(file, 'set-state',
>>> +                          event="flush_to_disk",
>>> +                          state="1",
>>> +                          new_state="2")
>>> +            blkdebug_rule(file, 'inject-error',
>>> +                          event="read_aio", errno="5",
>>> +                          state="2", immediately="off",
>>> +                          once="on")
>>> +
>>> +        # Create a blkdebug interface to this img as 'drive1'
>>> +        result = self.vm.qmp('blockdev-add', options={
>>> +            'id': 'drive1',
>>> +            'driver': iotests.imgfmt,
>>> +            'file': {
>>> +                'driver': 'blkdebug',
>>> +                'config': blkdebug,
>>> +                'image': {
>>> +                    'driver': 'file',
>>> +                    'filename': self.test_img
>>> +                }
>>> +            }
>>> +        })
>>
>> Awwww, I've written such a nice QMP interface and you won't use it? :'-(
>>
>> See test 071, I encourage you to try. ;-)
>>
>> Max
>>
>
> Aww, you're going to hold out on me for that?

Yes, not least because I would have to take a peek into Python's I/O 
functions first. ;-)

Max

> (Actually, I did notice when you reviewed my blkdebug patch but not 
> before then. This was already working so I just left it. (Though it is 
> nicer in that you don't have to create a file. (I'll look.)))
>
>>> +        self.assert_qmp(result, 'return', {})
>>> +
>>> +        self.create_full_backup()
>>> +        self.add_bitmap('bitmap0', 'drive1')
>>> +        self.vm.hmp("c")
>>> +        self.hmp_io_writes('drive1', (('0xab', 0, 512),
>>> +                                      ('0xfe', '16M', '256k'),
>>> +                                      ('0x64', '32736k', '64k')))
>>> +
>>> +        result = self.create_incremental(validate=False)
>>> +        self.assertFalse(result)
>>> +        self.hmp_io_writes('drive1', (('0x9a', 0, 512),
>>> +                                      ('0x55', '8M', '352k'),
>>> +                                      ('0x78', '15872k', '1M')))
>>> +        self.create_incremental()
>>> +
>>> +
>>>       def test_sync_dirty_bitmap_missing(self):
>>>           self.assert_no_active_block_jobs()
>>>           self.files.append(self.foo_img)
>>> diff --git a/tests/qemu-iotests/112.out b/tests/qemu-iotests/112.out
>>> index 89968f3..914e373 100644
>>> --- a/tests/qemu-iotests/112.out
>>> +++ b/tests/qemu-iotests/112.out
>>> @@ -1,5 +1,5 @@
>>> -....
>>> +.....
>>> ----------------------------------------------------------------------
>>> -Ran 4 tests
>>> +Ran 5 tests
>>>   OK
>>> diff --git a/tests/qemu-iotests/iotests.py
>>> b/tests/qemu-iotests/iotests.py
>>> index 6bff935..e452c40 100644
>>> --- a/tests/qemu-iotests/iotests.py
>>> +++ b/tests/qemu-iotests/iotests.py
>>> @@ -264,14 +264,16 @@ class QMPTestCase(unittest.TestCase):
>>>           self.assert_no_active_block_jobs()
>>>           return result
>>> -    def wait_until_completed(self, drive='drive0', check_offset=True):
>>> +    def wait_until_completed(self, drive='drive0', check_offset=True,
>>> +                             allow_failures=False):
>>>           '''Wait for a block job to finish, returning the event'''
>>>           completed = False
>>>           while not completed:
>>>               for event in self.vm.get_qmp_events(wait=True):
>>>                   if event['event'] == 'BLOCK_JOB_COMPLETED':
>>>                       self.assert_qmp(event, 'data/device', drive)
>>> -                    self.assert_qmp_absent(event, 'data/error')
>>> +                    if not allow_failures:
>>> +                        self.assert_qmp_absent(event, 'data/error')
>>>                       if check_offset:
>>>                           self.assert_qmp(event, 'data/offset',
>>> event['data']['len'])
>>>                       completed = True
>>