Re: [Qemu-devel] [PATCH] iotests: fix wait_until_completed()

[Kevin Wolf <kwolf@redhat.com>]

Am 26.03.2018 um 08:11 hat Peter Xu geschrieben:
> If there are more than one events, wait_until_completed() might return
> the 2nd event even if the 1st event is JOB_COMPLETED, since the for loop
> will continue to run even if completed is set to True.
> 
> It never happened before, but it can be triggered when OOB is enabled
> due to the RESUME startup message. Fix that up by removing the boolean
> and make sure we return the correct event.
> 
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
>  tests/qemu-iotests/iotests.py | 20 ++++++++------------
>  1 file changed, 8 insertions(+), 12 deletions(-)
> 
> diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
> index b5d7945af8..11704e6583 100644
> --- a/tests/qemu-iotests/iotests.py
> +++ b/tests/qemu-iotests/iotests.py
> @@ -470,18 +470,14 @@ class QMPTestCase(unittest.TestCase):
>  
>      def wait_until_completed(self, drive='drive0', check_offset=True):
>          '''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 check_offset:
> -                        self.assert_qmp(event, 'data/offset', event['data']['len'])
> -                    completed = True
> -
> -        self.assert_no_active_block_jobs()
> -        return event
> +        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 check_offset:
> +                    self.assert_qmp(event, 'data/offset', event['data']['len'])
> +                self.assert_no_active_block_jobs()
> +                return event
>  
>      def wait_ready(self, drive='drive0'):
>          '''Wait until a block job BLOCK_JOB_READY event'''

If an event is pending, but it's not the expected event, won't we return
None now instead of waiting for the BLOCK_JOB_COMPLETED event?

Wouldn't it be much easier to just add a 'break'?

Kevin