Re: [Qemu-devel] [PULL 01/17] migration: remove register_savevm()

[Peter Maydell]

On 6 June 2017 at 03:51, David Gibson <address@hidden> wrote:
> From: Laurent Vivier <address@hidden>
>
> We can replace the four remaining calls of register_savevm() by
> calls to register_savevm_live(). So we can remove the function and
> as we don't allocate anymore the ops pointer with g_new0()
> we don't have to free it then.
>
> Signed-off-by: Laurent Vivier <address@hidden>
> Reviewed-by: Juan Quintela <address@hidden>
> Signed-off-by: David Gibson <address@hidden>
> ---
>  hw/net/vmxnet3.c            |  8 ++++++--
>  hw/s390x/s390-skeys.c       |  9 +++++++--
>  hw/s390x/s390-virtio-ccw.c  |  8 ++++++--
>  include/migration/vmstate.h |  8 --------
>  migration/savevm.c          | 16 ----------------
>  slirp/slirp.c               |  8 ++++++--
>  6 files changed, 25 insertions(+), 32 deletions(-)

Great to see register_savevm() finally disappearing.

Any chance of an update to docs/migration.txt, which still
mentions register_savevm(), but on the other hand doesn't
say anything about register_savevm_live() and unregister_savevm().
(Doc comments in the .h file for those functions would be
nice too...)

Things that would be interesting to explain/document:
 * what is special about vmxnet3 that makes it the only pci device
   that needs to use this rather than having a vmstate struct?
 * why does s390-skeys call the register function with a NULL
   pointer but the unregister pointer with a device pointer?

(Could we replace the uses of these which pass a dev pointer
with vmstate structs and then drop the dev parameter?)

thanks
-- PMM