[sheepdog] [PATCH] sheep: fix a dead-lock bug in screen_object_list()

[levin li]

On 2012年11月26日 13:55, Liu Yuan wrote:
> On 11/26/2012 01:48 PM, levin li wrote:
>> screen_object_list() is called in recovery, if a VDI creation is in progress,
>> then the VDI creation operation is blocked by gateway to wait for completion of
>> recovery, and if we make screen_object_list() to retry infinitely to wait the
>> nr_objs to be not zero, which also means it waits for VDI creation to complete,
>> so, both VDI creation and recovery can not finish, it's a dead-lock.
>
> Hi Levin,
>    can you add a test for this case as tests/050? This will exclude the
> chance that others step in this problem again accidentally.
>
>    This is indeed a catastrophic bug that already destroyed a running
> cluster.
>
> Thanks,
> Yuan
>

I'd try to reproduce this problem in a test case, if I did it, I'll send 
it out.

thanks,

levin