Re: [Qemu-devel] [PATCH V8 1/2] Add a new qmp command to start/stop replication

[Zhang Chen]

On 02/23/2017 11:31 PM, Eric Blake wrote:
> On 02/23/2017 01:14 AM, Zhang Chen wrote:
> > We can call this qmp command to start/stop replication outside of qemu.
> > Like Xen colo need this function.
> >
> > Signed-off-by: Zhang Chen <address@hidden>
> > Signed-off-by: Wen Congyang <address@hidden>
> > Reviewed-by: Eric Blake <address@hidden>
> > Reviewed-by: Stefano Stabellini <address@hidden>
> > Reviewed-by: zhanghailiang <address@hidden>
> >
> > ---
> > @@ -104,6 +106,27 @@ void colo_do_failover(MigrationState *s)
> >       }
> >   }
> >   
> > +void qmp_xen_set_replication(bool enable, bool primary,
> > +                             bool has_failover, bool failover,
> > +                             Error **errp)
> > +{
> > +    ReplicationMode mode = primary ?
> > +                           REPLICATION_MODE_PRIMARY :
> > +                           REPLICATION_MODE_SECONDARY;
> > +
> > +    if (has_failover && enable) {
> > +        error_setg(errp, "Parameter 'failover' is only for"
> > +                   " stopping replication");
> > +        return;
> > +    }
> > +
> > +    if (enable) {
> > +        replication_start_all(mode, errp);
> > +    } else {
> > +        replication_stop_all(failover, failover ? NULL : errp);
> Technically, this is use of failover without first checking
> has_failover; it would be safer if you inserted:
>
> if (!has_failover) {
>      failover = NULL;
> }

OK, I will insert this code in next version.

Thanks
Zhang Chen

> earlier in the function to be safe against any callers that don't go
> through the QAPI-generated code.  Fortunately, our QAPI generated code
> guarantees that failover is NULL when has_failover is false, so my R-b
> can stand as-is if there is no other reason for a respin.

--
Thanks
Zhang Chen