[libvirt] xend_internal: Use domain/status for shutdown check

[Stefan Bader]

On 10.04.2012 15:22, Cole Robinson wrote:
> On 04/10/2012 04:46 AM, Stefan Bader wrote:
>> On 04/08/2012 03:08 PM, Cole Robinson wrote:
>>> On 04/02/2012 10:38 AM, Stefan Bader wrote:
>>>> xend_internal: Use domain/status for shutdown check
>>>>
>>>> On newer xend (v3.x and after) there is no state and domid reported
>>>> for inactive domains. When initially creating connections this is
>>>> handled in various places by assigning domain->id = -1.
>>>> But once an instance has been running, the id is set to the current
>>>> domain id. And it does not change when the instance is shut down.
>>>> So when querying the domain info, the hypervisor driver, which gets
>>>> asked first will indicate it cannot find information, then the
>>>> xend driver is asked and will set the status to NOSTATE because it
>>>> checks for the -1 domain id.
>>>> Checking domain/status for 0 seems to be more reliable for that.
>>>>
>>>> One note: I am not sure whether the domain->id also should get set
>>>> back to -1 whenever any sub-driver thinks the instance is no longer
>>>> running.
>>>>
>>>> BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=746007
>>>> BugLink: http://bugs.launchpad.net/bugs/929626
>>>>
>>>> Signed-off-by: Stefan Bader <stefan.bader at canonical.com>
>>>>
>>>> Index: libvirt-0.9.8/src/xen/xend_internal.c
>>>> ===================================================================
>>>> --- libvirt-0.9.8.orig/src/xen/xend_internal.c	2011-12-04 08:15:00.000000000 +0100
>>>> +++ libvirt-0.9.8/src/xen/xend_internal.c	2012-03-23 11:07:43.575529377 +0100
>>>> @@ -989,9 +989,11 @@
>>>>              state = VIR_DOMAIN_BLOCKED;
>>>>          else if (strchr(flags, 'r'))
>>>>              state = VIR_DOMAIN_RUNNING;
>>>> -    } else if (domain->id < 0) {
>>>> -        /* Inactive domains don't have a state reported, so
>>>> -           mark them SHUTOFF, rather than NOSTATE */
>>>> +    } else if (sexpr_int(root, "domain/status") == 0) {
>>>
>>> Maybe this should be
>>>
>>> (domain->id < 0 || sexpr_int(root, ...
>>>
>> It would not matter. Since the status is zero for all non-running domains it
>> covers those with domain->id < 0 as well.
>>
> 
> Even for RHEL5 vintage xen? Since we historically try to maintain
> compatibility with that. It may well work, but unless it's tested I don't
> think there's much harm in keeping the id < 0 check to preserve old behavior.
> 
> Thanks,
> Cole

I checked against CentOS5.5 (close enough). But right, it should not harm to
have it. I re-submit the patch as soon as I have recovered my failed attempt to
recover a raid failure... :/

-Stefan

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 900 bytes
Desc: OpenPGP digital signature
URL: <http://listman.redhat.com/archives/libvir-list/attachments/20120410/124253d6/attachment-0001.sig>