Re: [libvirt] [Qemu-devel] [PATCH] qdev: DEVICE_DELETED event
Eric Blake <eblake(a)redhat.com> writes:
[adding libvirt]
On 03/06/2013 07:52 AM, Paolo Bonzini wrote:
> Il 06/03/2013 15:44, Eric Blake ha scritto:
>> Question - if libvirt misses the event (for example, if libvirtd
>> requests a remove, but then gets restarted, and the event arrives before
>> libvirtd is back up), is there a way to poll whether the the removal has
>> completed? The event is great to minimize polling overhead in the
>> common case, but we generally provide this sort of information via a
>> pollable interface at the same time.
General rule: no event without a way to poll.
> Yes, you can use qom-list on /machine/peripheral.
Which means libvirt should be patched to use qom-list right now, even
before this event makes it in, in order to avoid its current bug of
reusing a device id before the deletion has completed. Adding the event
is still useful, as polling is never nice; and we already know how to
make libvirt do conditional code based on whether query-events shows
that the event has been added to minimize polling where possible.
Yes.