* Mark Cave-Ayland (mark.cave-ayl...@ilande.co.uk) wrote: > On 21/02/2022 17:11, Daniel P. Berrangé wrote: > > > On Sun, Feb 20, 2022 at 05:18:33PM +0000, Mark Cave-Ayland wrote: > > > On 08/02/2022 13:10, Daniel P. Berrangé wrote: > > > > > > > On Tue, Feb 08, 2022 at 01:06:59PM +0000, Mark Cave-Ayland wrote: > > > > > On 08/02/2022 12:49, Daniel P. Berrangé wrote: > > > > > > > > > > > > I was under the impression that monitor_register_hmp_info_hrt() > > > > > > > does all the > > > > > > > magic here i.e. it declares the underlying QMP command with an x- > > > > > > > prefix and > > > > > > > effectively encapsulates the text field in a way that says "this > > > > > > > is an > > > > > > > unreliable text opaque for humans"? > > > > > > > > > > > > The monitor_register_hmp_info_hrt only does the HMP glue side, and > > > > > > that's only needed if you must dynamically register the HMP command. > > > > > > For statically registered commands set '.cmd_info_hrt' directly in > > > > > > the hml-commands-info.hx for the HMP side. > > > > > > > > > > > > > If a qapi/ schema is needed could you explain what it should look > > > > > > > like for > > > > > > > this example and where it should go? Looking at the existing > > > > > > > .json files I > > > > > > > can't immediately see one which is the right place for this to > > > > > > > live. > > > > > > > > > > > > Take a look in qapi/machine.json for anyof the 'x-query-XXXX' > > > > > > commands > > > > > > there. The QAPI bit is fairly simple. > > > > > > > > > > > > if you want to see an illustration of what's different from a > > > > > > previous > > > > > > pure HMP impl, look at: > > > > > > > > > > > > commit dd98234c059e6bdb05a52998270df6d3d990332e > > > > > > Author: Daniel P. Berrangé <berra...@redhat.com> > > > > > > Date: Wed Sep 8 10:35:43 2021 +0100 > > > > > > > > > > > > qapi: introduce x-query-roms QMP command > > > > > > > > > > I see, thanks for the reference. So qapi/machine.json would be the > > > > > right > > > > > place to declare the QMP part even for a specific device? > > > > > > > > > > Even this approach still wouldn't work in its current form though, > > > > > since as > > > > > mentioned in my previous email it seems that only the target CONFIG_* > > > > > defines and not the device CONFIG_* defines are present when > > > > > processing > > > > > hmp-commands-info.hx. > > > > > > > > Yeah, that's where the pain comes in. While QAPI schema can be made > > > > conditional on a few CONFIG_* parameters - basically those derived > > > > from global configure time options, it is impossible for this to be > > > > with with target specific options like the device CONFIG_* defines. > > > > > > > > This is why I suggested in my othuer reply that it would need to be > > > > done with a generic 'info dev-debug' / 'x-query-dev-debug' command > > > > that can be registered unconditionally, and then individual devices > > > > plug into it. > > > > > > After some more experiments this afternoon I still seem to be falling > > > through the gaps on this one. This is based upon my understanding that all > > > new HMP commands should use a QMP HumanReadableText implementation and the > > > new command should be restricted according to target. > > > > > > Currently I am working with this change to hmp-commands-info.hx and > > > qapi/misc-target.json: > > > > [snip] > > > i.e. qmp_marshal_output_HumanReadableText() isn't protected by the #if > > > TARGET guards and since HumanReadableText is only used by the new > > > qmp_x_query_via() functionality then the compiler complains and aborts the > > > compilation. > > > > > > Possibly this is an error in the QAPI generator for types hidden behind > > > commands using "if"? Otherwise I'm not sure what is the best way to > > > proceed, > > > so I'd be grateful for some further pointers. > > > > Yes, this is pretty much what I expect and exactly what I hit with > > other target specific commands. > > > > That's why I suggested something like a general 'x-device-debug' command > > that is NOT conditionalized in QAPI, against which dev impls can register > > a callback to provide detailed reporting, instead of a device type specific > > command. > > Ah so this is a known issue with this approach then. David mentioned earlier > in the thread that he'd be okay with a HMP command if it was useful and > restricted to the required targets, so would it be okay to add "info via" > for now as just a (non-QMP wrapped) HMP info command if I can get that to > work?
I still am from an HMP point of view; it sounds like the right way in the future is to get the info devices or whatever; I suggest you keep it as close to a QMP implementation as possible, still with the HumanReadableText stuff. (Others might still be nervous about an HMP special; but I don't see it's worth holding this trivial stuff up for it). Dave > > ATB, > > Mark. > -- Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
