Re: [Qemu-devel] [V4 PATCH 2/5] net: announce self after vm start

[Jason Wang]

On 03/13/2012 10:23 PM, Michael S. Tsirkin wrote:
> On Tue, Mar 13, 2012 at 04:56:22PM +0800, Jason Wang wrote:
> > This patch moves qemu_announce_self() to vm_start() and add a new parameters to
> > control whether sending gratuitous packet is needed. There are several reasons
> > to do this:
> >
> > - Gratuitous packet is also needed when we resume a stopped vm or successfully
> >    load a state.
> Why is it needed when we continue a stopped vm?

If we stop a vm for a little long time, the mac table entry in the 
switch would also be expired. So we need to announce again.
> > - Sending gratuitous packets may be done through co-operation with guest, so
> >    this work should be done after vm is started.
> >
> > Signed-off-by: Jason Wang<address@hidden>
> > ---
> >   gdbstub.c   |    2 +-
> >   migration.c |    5 ++---
> >   monitor.c   |    2 +-
> >   qmp.c       |    2 +-
> >   savevm.c    |    2 +-
> >   sysemu.h    |    2 +-
> >   vl.c        |    7 +++++--
> >   7 files changed, 12 insertions(+), 10 deletions(-)
> >
> > diff --git a/gdbstub.c b/gdbstub.c
> > index ef95ac2..f4d22e5 100644
> > --- a/gdbstub.c
> > +++ b/gdbstub.c
> > @@ -371,7 +371,7 @@ static inline void gdb_continue(GDBState *s)
> >   #ifdef CONFIG_USER_ONLY
> >       s->running_state = 1;
> >   #else
> > -    vm_start();
> > +    vm_start(false);
> >   #endif
> >   }
> >
> > diff --git a/migration.c b/migration.c
> > index 00fa1e3..40332d2 100644
> > --- a/migration.c
> > +++ b/migration.c
> > @@ -88,14 +88,13 @@ void process_incoming_migration(QEMUFile *f)
> >           fprintf(stderr, "load of migration failed\n");
> >           exit(0);
> >       }
> > -    qemu_announce_self();
> >       DPRINTF("successfully loaded vm state\n");
> >
> >       /* Make sure all file formats flush their mutable metadata */
> >       bdrv_invalidate_cache_all();
> >
> >       if (autostart) {
> > -        vm_start();
> > +        vm_start(true);
> >       } else {
> >           runstate_set(RUN_STATE_PRELAUNCH);
> >       }
> > @@ -274,7 +273,7 @@ static void migrate_fd_put_ready(void *opaque)
> >           }
> >           if (s->state != MIG_STATE_COMPLETED) {
> >               if (old_vm_running) {
> > -                vm_start();
> > +                vm_start(false);
> >               }
> >           }
> >       }
> > diff --git a/monitor.c b/monitor.c
> > index cbdfbad..0b63c11 100644
> > --- a/monitor.c
> > +++ b/monitor.c
> > @@ -2260,7 +2260,7 @@ static void do_loadvm(Monitor *mon, const QDict *qdict)
> >       vm_stop(RUN_STATE_RESTORE_VM);
> >
> >       if (load_vmstate(name) == 0&&  saved_vm_running) {
> > -        vm_start();
> > +        vm_start(true);
> >       }
> >   }
> >
> > diff --git a/qmp.c b/qmp.c
> > index a182b51..252c842 100644
> > --- a/qmp.c
> > +++ b/qmp.c
> > @@ -160,7 +160,7 @@ void qmp_cont(Error **errp)
> >           return;
> >       }
> >
> > -    vm_start();
> > +    vm_start(true);
> >   }
> >
> >   void qmp_system_wakeup(Error **errp)
> > diff --git a/savevm.c b/savevm.c
> > index 5b59826..82b9d3a 100644
> > --- a/savevm.c
> > +++ b/savevm.c
> > @@ -2107,7 +2107,7 @@ void do_savevm(Monitor *mon, const QDict *qdict)
> >
> >    the_end:
> >       if (saved_vm_running)
> > -        vm_start();
> > +        vm_start(false);
> >   }
> >
> >   int load_vmstate(const char *name)
> > diff --git a/sysemu.h b/sysemu.h
> > index 98118cc..787edd4 100644
> > --- a/sysemu.h
> > +++ b/sysemu.h
> > @@ -34,7 +34,7 @@ void vm_state_notify(int running, RunState state);
> >   #define VMRESET_SILENT   false
> >   #define VMRESET_REPORT   true
> >
> > -void vm_start(void);
> > +void vm_start(bool announce);
> >   void vm_stop(RunState state);
> >   void vm_stop_force_state(RunState state);
> >
> > diff --git a/vl.c b/vl.c
> > index 65f11f2..4e04f82 100644
> > --- a/vl.c
> > +++ b/vl.c
> > @@ -1258,7 +1258,7 @@ void vm_state_notify(int running, RunState state)
> >       }
> >   }
> >
> > -void vm_start(void)
> > +void vm_start(bool announce)
> >   {
> >       if (!runstate_is_running()) {
> >           cpu_enable_ticks();
> > @@ -1266,6 +1266,9 @@ void vm_start(void)
> >           vm_state_notify(1, RUN_STATE_RUNNING);
> >           resume_all_vcpus();
> >           monitor_protocol_event(QEVENT_RESUME, NULL);
> > +        if (announce) {
> > +            qemu_announce_self();
> > +        }
> >       }
> >   }
> >
> > @@ -3619,7 +3622,7 @@ int main(int argc, char **argv, char **envp)
> >               exit(ret);
> >           }
> >       } else if (autostart) {
> > -        vm_start();
> > +        vm_start(false);
> >       }
> >
> >       os_setup_post();