[PATCH v2 2/6] qemu_driver: Probe capability before calculating dirty page rate

[Hyman Huang]

在 2022/1/27 16:23, Peter Krempa 写道:
> On Thu, Jan 27, 2022 at 15:25:18 +0800, huangy81 at chinatelecom.cn wrote:
>> From: Hyman Huang(黄勇) <huangy81 at chinatelecom.cn>
>>
>> Probing QEMU_CAPS_CALC_DIRTY_RATE capability in advance
>> in case of failure when calculating dirty page rate.
>>
>> Signed-off-by: Hyman Huang(黄勇) <huangy81 at chinatelecom.cn>
>> ---
>>   src/qemu/qemu_driver.c | 12 ++++++++++++
>>   1 file changed, 12 insertions(+)
>>
>> diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
>> index 0a1ba74..0e8e9b1 100644
>> --- a/src/qemu/qemu_driver.c
>> +++ b/src/qemu/qemu_driver.c
>> @@ -20647,10 +20647,22 @@ qemuDomainStartDirtyRateCalc(virDomainPtr dom,
>>       virQEMUDriver *driver = dom->conn->privateData;
>>       virDomainObj *vm = NULL;
>>       qemuDomainObjPrivate *priv;
>> +    g_autoptr(virQEMUCaps) qemucaps = NULL;
>>       int ret = -1;
>>   
>>       virCheckFlags(0, -1);
>>   
>> +    if (!(qemucaps = virQEMUCapsCacheLookupDefault(driver->qemuCapsCache,
>> +                                                   NULL, NULL, NULL, NULL,
>> +                                                   NULL, NULL, NULL)))
>> +        return -1;
> 
> This is not needed, qemuCaps for a running vm are stored in
> 'priv->qemuCaps'. In fact it's wrong to not use the stored capabilities