On Fri, Aug 05, 2016 at 06:53:49PM +0100, Dr. David Alan Gilbert wrote:
> * zhanghailiang (zhang.zhanghaili...@huawei.com) wrote:
> > We should not destroy the state of SVM (Secondary VM) until we receive
> > the whole state from the PVM (Primary VM), in case the primary fails in
> > the middle of sending the state, so, here we cache the device state in
> > Secondary before restore it.
> >
> > Besides, we should call qemu_system_reset() before load VM state,
> > which can ensure the data is intact.
> >
> > Signed-off-by: zhanghailiang <zhang.zhanghaili...@huawei.com>
> > Signed-off-by: Li Zhijian <lizhij...@cn.fujitsu.com>
> > Signed-off-by: Gonglei <arei.gong...@huawei.com>
> > Reviewed-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
> > Cc: Dr. David Alan Gilbert <dgilb...@redhat.com>
> > ---
> > v17:
> > - Replace the old buffer API with the new channel buffer API.
> > v16:
> > - Rename colo_get_cmd_value() to colo_receive_mesage_value();
> > v13:
> > - Fix the define of colo_get_cmd_value() to use 'Error **errp' instead of
> > return value.
> > v12:
> > - Use the new helper colo_get_cmd_value() instead of colo_ctl_get()
> > ---
> > migration/colo.c | 70
> > ++++++++++++++++++++++++++++++++++++++++++++++++++++++--
> > 1 file changed, 68 insertions(+), 2 deletions(-)
> >
> > diff --git a/migration/colo.c b/migration/colo.c
> > index 0401629..8fa2104 100644
> > --- a/migration/colo.c
> > +++ b/migration/colo.c
> > @@ -115,6 +115,28 @@ static void colo_receive_check_message(QEMUFile *f,
> > COLOMessage expect_msg,
> > }
> > }
> >
> > +static uint64_t colo_receive_message_value(QEMUFile *f, uint32_t
> > expect_msg,
> > + Error **errp)
> > +{
> > + Error *local_err = NULL;
> > + uint64_t value;
> > + int ret;
> > +
> > + colo_receive_check_message(f, expect_msg, &local_err);
> > + if (local_err) {
> > + error_propagate(errp, local_err);
> > + return 0;
> > + }
> > +
> > + value = qemu_get_be64(f);
> > + ret = qemu_file_get_error(f);
> > + if (ret < 0) {
> > + error_setg_errno(errp, -ret, "Failed to get value for COLO
> > message: %s",
> > + COLOMessage_lookup[expect_msg]);
> > + }
> > + return value;
> > +}
> > +
> > static int colo_do_checkpoint_transaction(MigrationState *s,
> > QIOChannelBuffer *bioc,
> > QEMUFile *fb)
> > @@ -286,6 +308,10 @@ static void colo_wait_handle_message(QEMUFile *f, int
> > *checkpoint_request,
> > void *colo_process_incoming_thread(void *opaque)
> > {
> > MigrationIncomingState *mis = opaque;
> > + QEMUFile *fb = NULL;
> > + QIOChannelBuffer *bioc = NULL; /* Cache incoming device state */
> > + uint64_t total_size;
> > + uint64_t value;
> > Error *local_err = NULL;
> > int ret;
> >
> > @@ -310,6 +336,10 @@ void *colo_process_incoming_thread(void *opaque)
> > goto out;
> > }
> >
> > + bioc = qio_channel_buffer_new(COLO_BUFFER_BASE_SIZE);
> > + fb = qemu_fopen_channel_input(QIO_CHANNEL(bioc));
> > + object_unref(OBJECT(bioc));
> > +
> > colo_send_message(mis->to_src_file, COLO_MESSAGE_CHECKPOINT_READY,
> > &local_err);
> > if (local_err) {
> > @@ -337,7 +367,30 @@ void *colo_process_incoming_thread(void *opaque)
> > goto out;
> > }
> >
> > - /* TODO: read migration data into colo buffer */
> > + value = colo_receive_message_value(mis->from_src_file,
> > + COLO_MESSAGE_VMSTATE_SIZE, &local_err);
> > + if (local_err) {
> > + goto out;
> > + }
> > +
> > + /*
> > + * Read VM device state data into channel buffer,
> > + * It's better to re-use the memory allocated.
> > + * Here we need to handle the channel buffer directly.
> > + */
> > + if (value > bioc->capacity) {
> > + bioc->capacity = value;
> > + bioc->data = g_realloc(bioc->data, bioc->capacity);
> > + }
>
> Dan: Are you ok with that, or should there be some io/channel-buffer.c call
> to do it?
While we could add APIs for this, I'm perfectly ok with the buffer
being updated directly too, as its a very simple struct.
Regards,
Daniel
--
|: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :|
|: http://libvirt.org -o- http://virt-manager.org :|
|: http://autobuild.org -o- http://search.cpan.org/~danberr/ :|
|: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|
