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

[Max Reitz]

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 <address@hidden>
> > > ---
> > >   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