Re: [Qemu-devel] [PATCH] xen: introduce xen_change_state_handler

[Stefano Stabellini <stefano.stabellini@eu.citrix.com>]

On Thu, 30 Jun 2011, Alexander Graf wrote:
> On 06/29/2011 01:16 PM, stefano.stabellini@eu.citrix.com wrote:
> > From: Anthony PERARD<anthony.perard@citrix.com>
> >
> > Remove the call to xenstore_record_dm_state from xen_main_loop_prepare
> > that is HVM specific.
> > Add a new vm_change_state_handler shared between xen_pv and xen_hvm
> > machines to record the VM state to xenstore.
> >
> > Signed-off-by: Anthony PERARD<anthony.perard@citrix.com>
> > Signed-off-by: Stefano Stabellini<stefano.stabellini@eu.citrix.com>
> > ---
> >   xen-all.c |   25 ++++++++++++++++++-------
> >   1 files changed, 18 insertions(+), 7 deletions(-)
> >
> > diff --git a/xen-all.c b/xen-all.c
> > index 3fd04ef..e8da35f 100644
> > --- a/xen-all.c
> > +++ b/xen-all.c
> > @@ -797,12 +797,17 @@ void xenstore_store_pv_console_info(int i, CharDriverState *chr)
> >       }
> >   }
> >
> > -static void xenstore_record_dm_state(XenIOState *s, const char *state)
> > +static void xenstore_record_dm_state(struct xs_handle *xs, const char *state)
> >   {
> >       char path[50];
> >
> > +    if (xs == NULL) {
> > +        fprintf(stderr, "xenstore connection not initialized\n");
> > +        exit(1);
> > +    }
> > +
> >       snprintf(path, sizeof (path), "/local/domain/0/device-model/%u/state", xen_domid);
> > -    if (!xs_write(s->xenstore, XBT_NULL, path, state, strlen(state))) {
> > +    if (!xs_write(xs, XBT_NULL, path, state, strlen(state))) {
> >           fprintf(stderr, "error recording dm state\n");
> >           exit(1);
> >       }
> > @@ -823,15 +828,20 @@ static void xen_main_loop_prepare(XenIOState *state)
> >       if (evtchn_fd != -1) {
> >           qemu_set_fd_handler(evtchn_fd, cpu_handle_ioreq, NULL, state);
> >       }
> > -
> > -    /* record state running */
> > -    xenstore_record_dm_state(state, "running");
> >   }
> >
> >
> >   /* Initialise Xen */
> >
> > -static void xen_vm_change_state_handler(void *opaque, int running, int reason)
> > +static void xen_change_state_handler(void *opaque, int running, int reason)
> > +{
> > +    if (running) {
> > +        /* record state running */
> > +        xenstore_record_dm_state(xenstore, "running");
> > +    }
> 
> So where is this ever executed in the PV case?
 
qemu_add_vm_change_state_handler(xen_change_state_handler, NULL) is now
called by xen_init, that is common between xen_pv and xen_fv machines