Re: [PATCH v3 27/30] hmp: QAPIfy object_add
Am 15.03.2021 um 10:39 hat Markus Armbruster geschrieben:
Paolo Bonzini <pbonzini(a)redhat.com> writes:
> On 13/03/21 14:28, Markus Armbruster wrote:
>> Kevin Wolf <kwolf(a)redhat.com> writes:
>>
>>> This switches the HMP command object_add from a QemuOpts-based parser to
>>> user_creatable_add_from_str() which uses a keyval parser and enforces
>>> the QAPI schema.
>>>
>>> Apart from being a cleanup, this makes non-scalar properties and help
>>> accessible. In order for help to be printed to the monitor instead of
>>> stdout, the printf() calls in the help functions are changed to
>>> qemu_printf().
>>>
>>> Signed-off-by: Kevin Wolf <kwolf(a)redhat.com>
>>> Acked-by: Peter Krempa <pkrempa(a)redhat.com>
>>> Reviewed-by: Eric Blake <eblake(a)redhat.com>
>>> Reviewed-by: Dr. David Alan Gilbert <dgilbert(a)redhat.com>
>>> ---
>>> monitor/hmp-cmds.c | 17 ++---------------
>>> qom/object_interfaces.c | 11 ++++++-----
>>> hmp-commands.hx | 2 +-
>>> 3 files changed, 9 insertions(+), 21 deletions(-)
>>>
>>> diff --git a/monitor/hmp-cmds.c b/monitor/hmp-cmds.c
>>> index 3c88a4faef..652cf9ff21 100644
>>> --- a/monitor/hmp-cmds.c
>>> +++ b/monitor/hmp-cmds.c
>>> @@ -1670,24 +1670,11 @@ void hmp_netdev_del(Monitor *mon, const QDict
*qdict)
>>>
>>> void hmp_object_add(Monitor *mon, const QDict *qdict)
>>> {
>>> + const char *options = qdict_get_str(qdict, "object");
>>> Error *err = NULL;
>>> - QemuOpts *opts;
>>> - Object *obj = NULL;
>>> -
>>> - opts = qemu_opts_from_qdict(qemu_find_opts("object"), qdict,
&err);
>>> - if (err) {
>>> - goto end;
>>> - }
>>>
>>> - obj = user_creatable_add_opts(opts, &err);
>>> - qemu_opts_del(opts);
>>> -
>>> -end:
>>> + user_creatable_add_from_str(options, &err);
>>> hmp_handle_error(mon, err);
>>> -
>>> - if (obj) {
>>> - object_unref(obj);
>>> - }
>>> }
>>
>> Doesn't this break the list-valued properties (Memdev member host-nodes,
>> NumaNodeOptions member cpus) exactly the same way that made us keep
>> QemuOpts for qemu-system-FOO -object?
>
> Yes, it does. I guess it can just be documented, unlike for the command
> line?
Maybe. Judgement call, not mine to make.
Do people create such objects in HMP? I figure we don't really know.
Educated guess?
If you try, how does it break? Is it confusing? Can you show an
example?
(qemu) object_add memory-backend-ram,id=mem,size=4G,policy=bind,host-nodes=0
Error: Invalid parameter type for 'host-nodes', expected: array
(qemu) object_add memory-backend-ram,id=mem,size=4G,policy=bind,host-nodes.0=0
(qemu)
HMP is not a stable interface, so changing the syntax didn't feel like a
problem to me. I doubt many people do HMP memory hotplug while setting a
specific NUMA policy, but it wouldn't change my assessment anyway. I
should have made this explicit in the commit message, though.
Kevin