Re: [PATCH 1/9] tests/qtest/arm-cpu-features: Remove Cortex-A15 check

[John Snow <jsnow@redhat.com>]

On 2/6/21 5:40 AM, Andrew Jones wrote:
>> BTW is there some easy way to dump QMP traffic on stdio?
> You can use scripts/qmp/qmp-shell to manually test stuff.
> 
> Thanks,
> drew
> 

If you enable debug logging in python too, it'll print to STDERR. This 
may or may not be useful depending on how the library is getting used 
and by whom.

(For iotests, you used to be able to engage this mode by passing -d. I 
don't know if the new test runner has changed this behavior. I'm sure 
avocado has something similar, somewhere, too.)

Otherwise, the runes are something like:

```
import logging

logging.basicConfig(level=logging.DEBUG)
```

but this only works once per process; the iotests entry point already 
has a call like this. To override it:

```
import logging

logging.getLogger().setLevel(logging.DEBUG)
```

There are other, more complex incantations; you can read 
https://docs.python.org/3/howto/logging.html if you'd like; the logger 
we care about is "QMP" (for QMP instances created without a 'nickname') 
and "QMP.{nickname}" for ones that were. So you can do this:

logging.getLogger("QMP").setLevel(logging.DEBUG)

but you might need to adjust other settings to get it to appear on 
STDERR (I don't remember), like setting handler propagation settings and 
so on.

--js