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

On 2/20/22 14:28, huangy81(a)chinatelecom.cn wrote: > From: Hyman Huang(黄勇) <huangy81(a)chinatelecom.cn&gt; > > 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(a)chinatelecom.cn&gt; > --- > 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.

> 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