Re: [Qemu-devel] [PATCH 5/5] migration/rdma: Send error during cancelling

[Peter Xu]

On Tue, Jul 04, 2017 at 07:49:15PM +0100, Dr. David Alan Gilbert (git) wrote:
> From: "Dr. David Alan Gilbert" <address@hidden>
> 
> When we issue a cancel and clean up the RDMA channel
> send a CONTROL_ERROR to get the destination to quit.
> 
> The rdma_cleanup code waits for the event to come back
> from the rdma_disconnect; but that wont happen until the
> destination quits and there's currently nothing to force
> it.
> 
> Note this makes the case of a cancel work while the destination
> is alive, and it already works if the destination is
> truly dead.  Note it doesn't fix the case where the destination
> is hung (we get stuck waiting for the rdma_disconnect event).
> 
> Signed-off-by: Dr. David Alan Gilbert <address@hidden>

Looks like we'll print this as well when we cancel the migration
(before sending the RDMA_CONTROL_ERROR):

  error_report("Early error. Sending error.");

But I don't think it really matters. So:

Reviewed-by: Peter Xu <address@hidden>

> ---
>  migration/rdma.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/migration/rdma.c b/migration/rdma.c
> index bfb0a43740..3d17db3a23 100644
> --- a/migration/rdma.c
> +++ b/migration/rdma.c
> @@ -2260,7 +2260,9 @@ static void qemu_rdma_cleanup(RDMAContext *rdma)
>      int ret, idx;
>  
>      if (rdma->cm_id && rdma->connected) {
> -        if (rdma->error_state && !rdma->received_error) {
> +        if ((rdma->error_state ||
> +             migrate_get_current()->state == MIGRATION_STATUS_CANCELLING) &&
> +            !rdma->received_error) {
>              RDMAControlHeader head = { .len = 0,
>                                         .type = RDMA_CONTROL_ERROR,
>                                         .repeat = 1,
> -- 
> 2.13.0
> 

-- 
Peter Xu