[PATCH v6 2/8] qemu_driver: Probe capability before calculating dirty page rate

[Hyman Huang]

在 2022/2/21 20:34, Michal Prívozník 写道:
> On 2/20/22 14:28, 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 | 8 +++++++-
>>   1 file changed, 7 insertions(+), 1 deletion(-)
>>
>> diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
>> index f1f708e..9b50f5f 100644
>> --- a/src/qemu/qemu_driver.c
>> +++ b/src/qemu/qemu_driver.c
>> @@ -20693,6 +20693,13 @@ qemuDomainStartDirtyRateCalc(virDomainPtr dom,
>>       if (virDomainStartDirtyRateCalcEnsureACL(dom->conn, vm->def) < 0)
>>           goto cleanup;
>>   
>> +    priv = vm->privateData;
>> +    if (!virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_CALC_DIRTY_RATE)) {
>> +        virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s",
>> +                       _("QEMU does not support calculating dirty page rate"));
>> +        goto cleanup;
>> +    }
>> +
> 
> Sorry for not telling you the whole truth. priv->qemuCaps is populated
> only when domain is running. Therefore for inactive domains this ^^^
> error message is reported which may be a bit misleading. But the fix is
> trivial, just check whether domain is active before querying priv-qemuCaps.
> 
Ok, got it :)
>>       if (qemuDomainObjBeginJob(driver, vm, QEMU_JOB_MODIFY) < 0)
>>           goto cleanup;
>>   
>> @@ -20704,7 +20711,6 @@ qemuDomainStartDirtyRateCalc(virDomainPtr dom,
>>   
>>       VIR_DEBUG("Calculate dirty rate in next %d seconds", seconds);
>>   
>> -    priv = vm->privateData;
>>       qemuDomainObjEnterMonitor(driver, vm);
>>       ret = qemuMonitorStartDirtyRateCalc(priv->mon, seconds);
>>   
> 
> Michal
> 

-- 
Best regard

Hyman Huang(黄勇)