On 2012-02-15 13:49, Luiz Capitulino wrote: > On Wed, 15 Feb 2012 09:59:07 +0100 > Jan Kiszka <jan.kis...@siemens.com> wrote: > >> On 2012-02-10 20:31, Luiz Capitulino wrote: >>> This is a rebase of Anthony's conversion, from his glib branch; and this is >>> also the beginning of the conversion of complex commands to the qapi. >>> >>> There are two important changes that should be observed: >>> >>> 1. patch 5/6 purges the 'mon' object from migration code. One of the >>> consequences is that we lose the ability to print progress status to >>> the HMP user (esp. in block migration) >> >> This smells extremely fishy. You have some common "monitor" context in >> both cases, means something that decides where suspend/resume takes >> effect or where to pick up file descriptors from. If the exiting Monitor >> object is not generic enough, introduce some super-class and use that in >> common services. Or make sure that a variant of Monitor is also valid >> over QMP. But don't remove the dependency from the API, while >> reintroducing it via the backdoor of cur_mon. > > What we really want to do here is to untangle HMP and QMP. Unfortunately, > the migrate command is one of those commands where the two are deeply > tangled and the split won't be perfect. > > However, the two cases you mention above are solvable: > > 1. suspend/resume: this is *really* a HMP feature and shouldn't be in any > QMP code path. This is correctly addressed in this series by moving it > to hmp_migrate()
Almost correctly. ;) > > 2. file descriptor passing: the new QMP server will support sessions and > we'll move statefull commands (like getfd) to it. When we do it, we'll > introduce a new API to get fds that won't depend on the monitor. However, > this requires all commands to be converted to the qapi first. Meanwhile > we use the qemu_get_fd() API. > > Note: qemu_get_fd() is temporary, it shouldn't be a problem to use it > (if it's not incorrect, of course, I honestly haven't fully tested it > yet). So there will be a common super-class of Monitor and that new QMP session that also manages the file descriptors? That would make sense. Still, there would be monitor_get_fd and qmp_get_fd then not qemu_get_fd. I think that should be done already. BTW, where do you get the FDs from now in QMP mode? Is there currently a Monitor instance associated? Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux
