Re: [Qemu-devel] [PATCH v7 00/12] rdma: migration support

["Michael R. Hines" <mrhines@linux.vnet.ibm.com>]

On 06/13/2013 05:40 PM, Paolo Bonzini wrote:
> Il 13/06/2013 17:17, Michael R. Hines ha scritto:
>> On 06/13/2013 04:06 PM, Paolo Bonzini wrote:
>>> Regarding the timestamp problem, it should be fixed in the RDMA code.
>>> You did find a bug, but xyz_start_outgoing_migration should be
>>> asynchronous and the pinning should happen in the setup phase.  This is
>>> because the setup phase is already running outside the big QEMU lock and
>>> the guest would not be frozen.
>> I think you misunderstood the symptom. The pinning is *already*
>> happening in the setup phase (xyz_start_outgoing_migration), not
>> inside the the migration_thread().
> I was referring to ram_control_before_iterate(f, RAM_CONTROL_SETUP).
> Even better, that would be a good reason to remove the
>
> +     * Please leave in place. These calls generate reserved messages in
> +     * the RDMA protocol in order to pre-register RDMA memory in the
> +     * future before the bulk round begins.
>
> comment that I don't like. :)
>
> xyz_start_outgoing_migration is the connect phase if you want to give it
> a name.
>
> The connect phase runs with the big QEMU lock taken, so any interrupt
> will freeze VCPUs until the pinning ends.

Excellent suggestions. I've re-submitted the patch already with these 
modifications as v8.

Thanks, Paolo.

>
> Juan, are you going to pick this up, or should Anthony do it?  (Michael:
> in any case, do not send a pull request yourself).

Understood =).