migration/dirtyrate: Extend dirtyrate statistics for domGetStats

Extend dirtyrate statistics for domGetStats to display the information
of a domain's memory dirty rate produced by domainStartDirtyRateCalc.

Signed-off-by: Hao Wang <wanghao232@huawei.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>

include/libvirt/libvirt-domain.h

@@ -2185,6 +2185,7 @@ typedef enum {
     VIR_DOMAIN_STATS_PERF = (1 << 6), /* return domain perf event info */
     VIR_DOMAIN_STATS_IOTHREAD = (1 << 7), /* return iothread poll info */
     VIR_DOMAIN_STATS_MEMORY = (1 << 8), /* return domain memory info */
+    VIR_DOMAIN_STATS_DIRTYRATE = (1 << 9), /* return domain dirty rate info */
 } virDomainStatsTypes;
 
 typedef enum {

src/libvirt-domain.c

@@ -11887,6 +11887,21 @@ virConnectGetDomainCapabilities(virConnectPtr conn,
  *                       bytes consumed by @vcpus that passing through all
  *                       memory controllers, either local or remote controller.
  *
+ * VIR_DOMAIN_STATS_DIRTYRATE:
+ *     Return memory dirty rate information. The typed parameter keys are in
+ *     this format:
+ *
+ *     "dirtyrate.calc_status" - the status of last memory dirty rate calculation,
+ *                               returned as int from virDomainDirtyRateStatus
+ *                               enum.
+ *     "dirtyrate.calc_start_time" - the start time of last memory dirty rate
+ *                                   calculation as long long.
+ *     "dirtyrate.calc_period" - the period of last memory dirty rate calculation
+ *                               as int.
+ *     "dirtyrate.megabytes_per_second" - the calculated memory dirty rate in
+ *                                        MiB/s as long long. It is produced
+ *                                        only if the calc_status is measured.
+ *
  * Note that entire stats groups or individual stat fields may be missing from
  * the output in case they are not supported by the given hypervisor, are not
  * applicable for the current state of the guest domain, or their retrieval

src/qemu/qemu_driver.c

@@ -18577,6 +18577,56 @@ qemuDomainGetStatsPerf(virQEMUDriverPtr driver G_GNUC_UNUSED,
     return 0;
 }
 
+static int
+qemuDomainGetStatsDirtyRateMon(virQEMUDriverPtr driver,
+                               virDomainObjPtr vm,
+                               qemuMonitorDirtyRateInfoPtr info)
+{
+    qemuDomainObjPrivatePtr priv = vm->privateData;
+    int ret;
+
+    qemuDomainObjEnterMonitor(driver, vm);
+    ret = qemuMonitorQueryDirtyRate(priv->mon, info);
+    if (qemuDomainObjExitMonitor(driver, vm) < 0)
+        ret = -1;
+
+    return ret;
+}
+
+static int
+qemuDomainGetStatsDirtyRate(virQEMUDriverPtr driver,
+                           virDomainObjPtr dom,
+                           virTypedParamListPtr params,
+                           unsigned int privflags)
+{
+    qemuMonitorDirtyRateInfo info;
+
+    if (!HAVE_JOB(privflags) || !virDomainObjIsActive(dom))
+        return 0;
+
+    if (qemuDomainGetStatsDirtyRateMon(driver, dom, &info) < 0)
+        return -1;
+
+    if (virTypedParamListAddInt(params, info.status,
+                                "dirtyrate.calc_status") < 0)
+        return -1;
+
+    if (virTypedParamListAddLLong(params, info.startTime,
+                                  "dirtyrate.calc_start_time") < 0)
+        return -1;
+
+    if (virTypedParamListAddInt(params, info.calcTime,
+                                "dirtyrate.calc_period") < 0)
+        return -1;
+
+    if ((info.status == VIR_DOMAIN_DIRTYRATE_MEASURED) &&
+        virTypedParamListAddLLong(params, info.dirtyRate,
+                                  "dirtyrate.megabytes_per_second") < 0)
+        return -1;
+
+    return 0;
+}
+
 typedef int
 (*qemuDomainGetStatsFunc)(virQEMUDriverPtr driver,
                           virDomainObjPtr dom,
@@ -18599,6 +18649,7 @@ static struct qemuDomainGetStatsWorker qemuDomainGetStatsWorkers[] = {
     { qemuDomainGetStatsPerf, VIR_DOMAIN_STATS_PERF, false },
     { qemuDomainGetStatsIOThread, VIR_DOMAIN_STATS_IOTHREAD, true },
     { qemuDomainGetStatsMemory, VIR_DOMAIN_STATS_MEMORY, false },
+    { qemuDomainGetStatsDirtyRate, VIR_DOMAIN_STATS_DIRTYRATE, true },
     { NULL, 0, false }
 };