On Thu, Jun 28, 2018 at 09:04:19AM +0200, Markus Armbruster wrote: > Eric Blake <ebl...@redhat.com> writes: > > > On 06/27/2018 07:07 AM, Peter Xu wrote: > > > >>>> Worse than that - broadcasting to all monitors is categorically broken. > >>>> Different monitors make use the same "id" formatting scheme, so if you > >>>> broadcast COMMAND_DROPPED to a different monitor you might have clashing > >>>> "id" and thus incorrectly tell a client its command was dropped when in > >>>> fact it was processed. You'd have to be fairly unlucky in timing, but > >>>> it could happen. > >>> > >>> Right. Must fix bug. > >> > > > >> > >> My current plan is that I can touch up scripts/qapi/events.py and > >> related stuff to allow QMPEventFuncEmit to take a monitor parameter, > >> then we pass in NULL when we want to send the event to all monitors. > >> > >> Would that work? > > > > Makes sense to me. Also, right now, ALL callers of qapi_event_send_* > > pass &error_abort as their final parameter. If you're refactoring > > everything anyways, you could get rid of that parameter on the > > presumption that it doesn't buy us anything. > > Let me try to turn presumption into fact :) > > The generated qapi_event_send_FOO() can detect the following error > conditions: > > * Visitor fails. But the QObject output visitor can't actually fail. > > Since the errp parameter is part of the abstract visitor interface, we > can't eliminate it. We can pass &error_abort. > > * emit() function fails. Can't happen, either. > > Let's eliminate the unused errp parameter of QMPEventFuncEmit.
Hmm, I think I got your point. > > If we can eliminate the somewhat silly indirection through > qmp_event_get_func_emit(), even better. It confused me before on why we had that after all. Let me give it a shot. Regards, -- Peter Xu
