Re: [Qemu-devel] [PATCH 5/5] runstate: Allow user to migrate twice

[Paolo Bonzini <pbonzini@redhat.com>]

On 10/14/2011 07:26 PM, Luiz Capitulino wrote:
> It should be a matter of allowing the transition POSTMIGRATE ->
> FINISH_MIGRATE, but it turns out that the VM won't do the
> transition the second time because it's already stopped.
>
> So this commit also adds vm_stop_force_state() which performs
> the transition even if the VM is already stopped.
>
> While there also allow other states to migrate.
>
> Signed-off-by: Luiz Capitulino<lcapitulino@redhat.com>
> ---
>   cpus.c      |   11 +++++++++++
>   migration.c |    2 +-
>   sysemu.h    |    1 +
>   vl.c        |    9 +++++++--
>   4 files changed, 20 insertions(+), 3 deletions(-)
>
> diff --git a/cpus.c b/cpus.c
> index 8978779..5f5b763 100644
> --- a/cpus.c
> +++ b/cpus.c
> @@ -887,6 +887,17 @@ void vm_stop(RunState state)
>       do_vm_stop(state);
>   }
>
> +/* does a state transition even if the VM is already stopped,
> +   current state is forgotten forever */
> +void vm_stop_force_state(RunState state)
> +{
> +    if (runstate_is_running()) {
> +        vm_stop(state);
> +    } else {
> +        runstate_set(state);
> +    }
> +}
> +
>   static int tcg_cpu_exec(CPUState *env)
>   {
>       int ret;
> diff --git a/migration.c b/migration.c
> index 77a51ad..62b74a6 100644
> --- a/migration.c
> +++ b/migration.c
> @@ -375,7 +375,7 @@ void migrate_fd_put_ready(void *opaque)
>           int old_vm_running = runstate_is_running();
>
>           DPRINTF("done iterating\n");
> -        vm_stop(RUN_STATE_FINISH_MIGRATE);
> +        vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
>
>           if ((qemu_savevm_state_complete(s->mon, s->file))<  0) {
>               if (old_vm_running) {
> diff --git a/sysemu.h b/sysemu.h
> index a889d90..7d288f8 100644
> --- a/sysemu.h
> +++ b/sysemu.h
> @@ -35,6 +35,7 @@ void vm_state_notify(int running, RunState state);
>
>   void vm_start(void);
>   void vm_stop(RunState state);
> +void vm_stop_force_state(RunState state);
>
>   void qemu_system_reset_request(void);
>   void qemu_system_shutdown_request(void);
> diff --git a/vl.c b/vl.c
> index 2e991fc..103a0df 100644
> --- a/vl.c
> +++ b/vl.c
> @@ -339,17 +339,20 @@ static const RunStateTransition runstate_transitions_def[] = {
>       { RUN_STATE_INMIGRATE, RUN_STATE_PRELAUNCH },
>
>       { RUN_STATE_INTERNAL_ERROR, RUN_STATE_PAUSED },
> +    { RUN_STATE_INTERNAL_ERROR, RUN_STATE_FINISH_MIGRATE },
>
>       { RUN_STATE_IO_ERROR, RUN_STATE_RUNNING },
> +    { RUN_STATE_IO_ERROR, RUN_STATE_FINISH_MIGRATE },
>
>       { RUN_STATE_PAUSED, RUN_STATE_RUNNING },
> -    { RUN_STATE_PAUSED, RUN_STATE_POSTMIGRATE },
> +    { RUN_STATE_PAUSED, RUN_STATE_FINISH_MIGRATE },
>
>       { RUN_STATE_POSTMIGRATE, RUN_STATE_RUNNING },
> +    { RUN_STATE_POSTMIGRATE, RUN_STATE_FINISH_MIGRATE },
>
>       { RUN_STATE_PRELAUNCH, RUN_STATE_RUNNING },
> +    { RUN_STATE_PRELAUNCH, RUN_STATE_FINISH_MIGRATE },
>       { RUN_STATE_PRELAUNCH, RUN_STATE_INMIGRATE },
> -    { RUN_STATE_PRELAUNCH, RUN_STATE_POSTMIGRATE },
>
>       { RUN_STATE_FINISH_MIGRATE, RUN_STATE_RUNNING },
>       { RUN_STATE_FINISH_MIGRATE, RUN_STATE_POSTMIGRATE },
> @@ -369,8 +372,10 @@ static const RunStateTransition runstate_transitions_def[] = {
>       { RUN_STATE_SAVE_VM, RUN_STATE_RUNNING },
>
>       { RUN_STATE_SHUTDOWN, RUN_STATE_PAUSED },
> +    { RUN_STATE_SHUTDOWN, RUN_STATE_FINISH_MIGRATE },
>
>       { RUN_STATE_WATCHDOG, RUN_STATE_RUNNING },
> +    { RUN_STATE_WATCHDOG, RUN_STATE_FINISH_MIGRATE },
>
>       { RUN_STATE_MAX, RUN_STATE_MAX },
>   };

Belatedly-Acked-by: Paolo Bonzini <pbonzini@redhat.com>

Paolo