[libvirt] [PATCH v2 1/3] qemu: Move allow reboot check setting

[John Ferlan]

On 11/6/18 4:38 AM, Michal Privoznik wrote:
> On 11/01/2018 05:04 PM, John Ferlan wrote:
>> Checking and setting the priv->allowReboot can be done before we start
>> processing the job. A subsequent patch will make use of the value to
>> make decisions in the error label, so we need to have it set properly.
>>
>> Signed-off-by: John Ferlan <jferlan at redhat.com>
>> ---
>>  src/qemu/qemu_process.c | 8 ++++----
>>  1 file changed, 4 insertions(+), 4 deletions(-)
>>
>> diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
>> index 9cf971808c..5232f761af 100644
>> --- a/src/qemu/qemu_process.c
>> +++ b/src/qemu/qemu_process.c
>> @@ -7767,6 +7767,10 @@ qemuProcessReconnect(void *opaque)
>>      cfg = virQEMUDriverGetConfig(driver);
>>      priv = obj->privateData;
>>  
>> +    /* If we are connecting to a guest started by old libvirt there is no
>> +     * allowReboot in status XML and we need to initialize it. */
>> +    qemuProcessPrepareAllowReboot(obj);
> 
> I'm not quite sure why this happens outside of job. It doesn't look like
> it has to.
> 

Is there a reason in your opinion it needs to occur inside a job? It is
a void function.

It's moved to prior to the first "goto error" because of patch3 which
would call qemuDomainIsUsingNoShutdown which checks priv->allowReboot
which is possibly set in *AllowReboot. Without that move, the code would
need to be reworked, which is fine, but understanding the reason why I
wrote things the way I did is important, IMO. I can add a comment to
"warn" the next person trying to move it that the error: logic uses the
->allowReboot value.

The allowReboot alteration has nothing to do with a job AFAICT and
whether on error: there is a job or not. Perhaps no different to what
qemuDomainObjRestoreJob is doing by using @priv fields for @oldjob.

Although looking at and quickly thinking about the code now, I wonder if
the virQEMUDriverGetCapabilities and goto error should be inside a job
too since error would then call qemuProcessStop without being in a job.

If this is dropped then logic in patch3 needs to be altered in order to
account for jobStarted = true... I think that got too messy when I first
thought about it.

Tks -

John

>> +
>>      if (!(caps = virQEMUDriverGetCapabilities(driver, false)))
>>          goto error;
>>  
>> @@ -7783,10 +7787,6 @@ qemuProcessReconnect(void *opaque)
>>      if (qemuDomainMasterKeyReadFile(priv) < 0)
>>          goto error;
>>  
>> -    /* If we are connecting to a guest started by old libvirt there is no
>> -     * allowReboot in status XML and we need to initialize it. */
>> -    qemuProcessPrepareAllowReboot(obj);
>> -
>>      if (qemuHostdevUpdateActiveDomainDevices(driver, obj->def) < 0)
>>          goto error;
>>  
>>
> 
> Michal
>