Re: [Qemu-devel] [PATCH 3/5] QMP: Introduce MIGRATION events

[Anthony Liguori <anthony@codemonkey.ws>]

On 05/25/2010 09:21 AM, Juan Quintela wrote:
> They are emitted when migration starts, ends, has a failure or is canceled.
>
> Signed-off-by: Juan Quintela<quintela@redhat.com>
> ---
>   QMP/qmp-events.txt |   50 ++++++++++++++++++++++++++++++++++++++++++++++++++
>   monitor.c          |   12 ++++++++++++
>   monitor.h          |    4 ++++
>   3 files changed, 66 insertions(+), 0 deletions(-)
>
> diff --git a/QMP/qmp-events.txt b/QMP/qmp-events.txt
> index 01ec85f..93caa4d 100644
> --- a/QMP/qmp-events.txt
> +++ b/QMP/qmp-events.txt
> @@ -26,6 +26,56 @@ Example:
>   Note: If action is "stop", a STOP event will eventually follow the
>   BLOCK_IO_ERROR event.
>    


> +MIGRATION_CANCELED
> +------------------
> +
> +Emitted when migration is canceled.  This is emitted in the source.
> +Target will emit MIGRATION_FAILED (no way to differentiate a FAILED
> +and CANCELED migration for target).
>    

But the management tool is the one that cancels so surely, it knows why 
already.

> +Data: None
> +
> +Example:
> +
> +{ "event": "MIGRATION_CANCELED",
> +    "timestamp": {"seconds": 1274687575, "microseconds": 592483} }
> +
> +MIGRATION_ENDED
> +---------------
> +
> +Emitted when migration ends (both in source and target)
>    

A start event is going to be generated already, no?

> +Data: None
> +
> +Example:
> +
> +{ "event": "MIGRATION_ENDED",
> +    "timestamp": {"seconds": 1274687575, "microseconds": 592483} }
> +
> +MIGRATION_FAILED
> +----------------
> +
> +Emitted when migration fails (both is source and target).
> +
> +Data: None
>    

There should be some information about why it failed, no? Preferrably in 
a QError format.

> +Example:
> +
> +{ "event": "MIGRATION_FAILED",
> +    "timestamp": {"seconds": 1274687575, "microseconds": 592483} }
> +
> +MIGRATION_STARTED
> +-----------------
> +
> +Emitted when migration starts (both in source and target).
>    

I think this makes more sense as a MIGRATION_CONNECTED event.  It 
probably should carry peer information too.

Regards,

Anthony Liguori

> +Data: None
> +
> +Example:
> +
> +{ "event": "MIGRATION_STARTED",
> +    "timestamp": {"seconds": 1274687575, "microseconds": 592483} }
> +
>   RESET
>   -----
>
> diff --git a/monitor.c b/monitor.c
> index ad50f12..5158780 100644
> --- a/monitor.c
> +++ b/monitor.c
> @@ -444,6 +444,18 @@ void monitor_protocol_event(MonitorEvent event, QObject *data)
>           case QEVENT_WATCHDOG:
>               event_name = "WATCHDOG";
>               break;
> +        case QEVENT_MIGRATION_STARTED:
> +            event_name = "MIGRATION_STARTED";
> +            break;
> +        case QEVENT_MIGRATION_ENDED:
> +            event_name = "MIGRATION_ENDED";
> +            break;
> +        case QEVENT_MIGRATION_FAILED:
> +            event_name = "MIGRATION_FAILED";
> +            break;
> +        case QEVENT_MIGRATION_CANCELED:
> +            event_name = "MIGRATION_CANCELED";
> +            break;
>           default:
>               abort();
>               break;
> diff --git a/monitor.h b/monitor.h
> index ea15469..34bcd38 100644
> --- a/monitor.h
> +++ b/monitor.h
> @@ -28,6 +28,10 @@ typedef enum MonitorEvent {
>       QEVENT_BLOCK_IO_ERROR,
>       QEVENT_RTC_CHANGE,
>       QEVENT_WATCHDOG,
> +    QEVENT_MIGRATION_STARTED,
> +    QEVENT_MIGRATION_ENDED,
> +    QEVENT_MIGRATION_FAILED,
> +    QEVENT_MIGRATION_CANCELED,
>       QEVENT_MAX,
>   } MonitorEvent;
>
>