[libvirt] [PATCH 2/4] qemu: Check QEMU_CAPS_OBJECT_IOTHREAD for qemuDomainPinIOThread

[John Ferlan]

On 10/13/2015 12:10 PM, Peter Krempa wrote:
> On Tue, Oct 13, 2015 at 11:47:08 -0400, John Ferlan wrote:
>> https://bugzilla.redhat.com/show_bug.cgi?id=1249981
>>
>> When trying to pin the thread to the live process in qemuDomainPinIOThread,
>> there was no check whether the binary supported IOThreads, thus thread_id = 0
>> (eg current) would be erroneously used.
>>
>> Follow qemuDomainChgIOThread and only check for the bit if changing
>> the live definition vs. changing the persistent definition.
>>
>> Signed-off-by: John Ferlan <jferlan at redhat.com>
>> ---
>>  src/qemu/qemu_driver.c | 6 ++++++
>>  1 file changed, 6 insertions(+)
>>
>> diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
>> index 8cd5ee3..7308c3b 100644
>> --- a/src/qemu/qemu_driver.c
>> +++ b/src/qemu/qemu_driver.c
>> @@ -5813,6 +5813,12 @@ qemuDomainPinIOThread(virDomainPtr dom,
>>          virDomainIOThreadIDDefPtr iothrid;
>>          virBitmapPtr cpumask;
>>  
>> +        if (!virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_OBJECT_IOTHREAD)) {
>> +            virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
>> +                           _("IOThreads not supported with this binary"));
>> +            goto endjob;
>> +        }
>> +
>>          if (!(iothrid = virDomainIOThreadIDFind(def, iothread_id))) {
>>              virReportError(VIR_ERR_INVALID_ARG,
>>                             _("iothread %d not found"), iothread_id);
> 
> Here this function should return that the iothread could not be found as
> such VM shouldn't allow any iothreads if we don't support them.
> 
>
I think it's preferable to have consistent error messages. See
qemuDomainGetIOThreadsLive and qemuDomainChgIOThread.

Giving a message such as iothread could not be found is I believe
misleading.

John