Re: [libvirt] [PATCH 2/5] qemu: Store supported migration capabilities in a bitmap

On 10/18/2017 07:29 AM, Jiri Denemark wrote: > Each time we need to check whether a given migration capability is > supported by QEMU, we call query-migrate-capabilities QMP command and > lookup the capability in the returned list. Asking for the list of > supported capabilities once when we connect to QEMU and storing the > result in a bitmap is much better and we don't need to enter a monitor > just to check whether a migration capability is supported. > > Signed-off-by: Jiri Denemark <jdenemar(a)redhat.com&gt; > --- > src/qemu/qemu_domain.c | 68 +++++++++++++++++++++++++++++++++++++++++++++++++ > src/qemu/qemu_domain.h | 9 +++++++ > src/qemu/qemu_process.c | 13 +--------- > 3 files changed, 78 insertions(+), 12 deletions(-) > There's no corresponding adjustment to qemuDomainObjPrivateXMLFormat and qemuDomainObjPrivateXMLParse in order to handle the restart scenario. The rest of this looks OK, but do you need the Format/Parse logic for the bitmap?

> diff --git a/src/qemu/qemu_domain.h b/src/qemu/qemu_domain.h > index 5201c6a0ac..fb20d8ea63 100644 > --- a/src/qemu/qemu_domain.h > +++ b/src/qemu/qemu_domain.h > @@ -323,6 +323,10 @@ struct _qemuDomainObjPrivate { > > /* Tracks blockjob state for vm. Valid only while reconnecting to qemu. */ > virTristateBool reconnectBlockjobs; > + > + /* Migration capabilities. Rechecked on reconnect, not to be saved in > + * private XML. */ > + virBitmapPtr migrationCaps; > };