[PATCH v1 2/6] qemu_driver: Probe capability before calculating dirty page rate

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 | 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; + + if (!virQEMUCapsGet(qemucaps, QEMU_CAPS_CALC_DIRTY_RATE)) { + virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s", + _("QEMU does not support calculating dirty page rate")); + return -1; + } + if (seconds < MIN_DIRTYRATE_CALC_PERIOD || seconds > MAX_DIRTYRATE_CALC_PERIOD) { virReportError(VIR_ERR_CONFIG_UNSUPPORTED, -- 1.8.3.1