Re: [Qemu-devel] [PATCH V3 6/7] Migration/colo.c: Add the necessary checks for colo_do_failover

[Zhang, Chen]

-----Original Message-----
From: Dr. David Alan Gilbert [mailto:address@hidden 
Sent: Saturday, March 9, 2019 1:41 AM
To: Zhang, Chen <address@hidden>
Cc: Li Zhijian <address@hidden>; Zhang Chen <address@hidden>; Juan Quintela 
<address@hidden>; zhanghailiang <address@hidden>; Markus Armbruster 
<address@hidden>; Eric Blake <address@hidden>; qemu-dev <address@hidden>
Subject: Re: [PATCH V3 6/7] Migration/colo.c: Add the necessary checks for 
colo_do_failover

* Zhang Chen (address@hidden) wrote:
> From: Zhang Chen <address@hidden>
> 
> Signed-off-by: Zhang Chen <address@hidden>

OK, we should make that properly return an error.
(Actually we should make the failover command be one of the new OOB commands; 
so that it can work even if the main loop is blocked- that would make COLO 
robust properly against network failures)

Good idea~ which OOB command can be the demo in current Qemu?
Maybe I can do this job in the future.

Thanks
Zhang Chen

Reviewed-by: Dr. David Alan Gilbert <address@hidden>

> ---
>  migration/colo.c | 10 ++++++++--
>  1 file changed, 8 insertions(+), 2 deletions(-)
> 
> diff --git a/migration/colo.c b/migration/colo.c index 
> dbe2b88807..d1ae2e6d11 100644
> --- a/migration/colo.c
> +++ b/migration/colo.c
> @@ -197,10 +197,16 @@ void colo_do_failover(MigrationState *s)
>          vm_stop_force_state(RUN_STATE_COLO);
>      }
>  
> -    if (get_colo_mode() == COLO_MODE_PRIMARY) {
> +    switch (get_colo_mode()) {
> +    case COLO_MODE_PRIMARY:
>          primary_vm_do_failover();
> -    } else {
> +        break;
> +    case COLO_MODE_SECONDARY:
>          secondary_vm_do_failover();
> +        break;
> +    default:
> +        error_report("colo_do_failover failed because the colo mode"
> +                     " could not be obtained");
>      }
>  }
>  
> --
> 2.17.GIT
> 
--
Dr. David Alan Gilbert / address@hidden / Manchester, UK