migration: add new migration state wait-unplug

This patch adds a new migration state called wait-unplug.  It is entered
after the SETUP state if failover devices are present. It will transition
into ACTIVE once all devices were succesfully unplugged from the guest.

So if a guest doesn't respond or takes long to honor the unplug request
the user will see the migration state 'wait-unplug'.

In the migration thread we query failover devices if they're are still
pending the guest unplug. When all are unplugged the migration
continues. If one device won't unplug migration will stay in wait_unplug
state.

Signed-off-by: Jens Freimann <jfreimann@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20191029114905.6856-9-jfreimann@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Jens Freimann 2019-10-29 12:49:02 +01:00 committed by Michael S. Tsirkin
parent a1190ab628
commit c7e0acd5a3
6 changed files with 63 additions and 1 deletions

View file

@ -186,6 +186,8 @@ struct VMStateDescription {
int (*pre_save)(void *opaque);
int (*post_save)(void *opaque);
bool (*needed)(void *opaque);
bool (*dev_unplug_pending)(void *opaque);
const VMStateField *fields;
const VMStateDescription **subsections;
};