util: Extend virresctl API to retrieve multiple monitor statistics

Export virResctrlMonitorGetStats and make
virResctrlMonitorGetCacheOccupancy obsoleted.

Signed-off-by: Wang Huaqiang <huaqiang.wang@intel.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>

src/libvirt_private.syms

@@ -2835,6 +2835,7 @@ virResctrlMonitorCreate;
 virResctrlMonitorDeterminePath;
 virResctrlMonitorGetCacheOccupancy;
 virResctrlMonitorGetID;
+virResctrlMonitorGetStats;
 virResctrlMonitorNew;
 virResctrlMonitorRemove;
 virResctrlMonitorSetAlloc;

src/qemu/qemu_driver.c

@@ -20710,6 +20710,7 @@ qemuDomainFreeResctrlMonData(virQEMUResctrlMonDataPtr resdata)
 /**
  * qemuDomainGetResctrlMonData:
  * @dom: Pointer for the domain that the resctrl monitors reside in
+ * @driver: Pointer to qemu driver
  * @resdata: Pointer of virQEMUResctrlMonDataPtr pointer for receiving the
  *            virQEMUResctrlMonDataPtr array. Caller is responsible for
  *            freeing the array.
@@ -20727,16 +20728,32 @@ qemuDomainFreeResctrlMonData(virQEMUResctrlMonDataPtr resdata)
  * Returns -1 on failure, or 0 on success.
  */
 static int
-qemuDomainGetResctrlMonData(virDomainObjPtr dom,
+qemuDomainGetResctrlMonData(virQEMUDriverPtr driver,
+                            virDomainObjPtr dom,
                             virQEMUResctrlMonDataPtr **resdata,
                             size_t *nresdata,
                             virResctrlMonitorType tag)
 {
     virDomainResctrlDefPtr resctrl = NULL;
     virQEMUResctrlMonDataPtr res = NULL;
+    char **features = NULL;
+    virCapsPtr caps = NULL;
     size_t i = 0;
     size_t j = 0;
 
+    caps = virQEMUDriverGetCapabilities(driver, false);
+
+    if (tag == VIR_RESCTRL_MONITOR_TYPE_CACHE) {
+        features = caps->host.cache.monitor->features;
+    } else {
+        virReportError(VIR_ERR_ARGUMENT_UNSUPPORTED, "%s",
+                       _("Unsupported resctrl monitor type"));
+        return -1;
+    }
+
+    if (virStringListLength((const char * const *)features) == 0)
+        return 0;
+
     for (i = 0; i < dom->def->nresctrls; i++) {
         resctrl = dom->def->resctrls[i];
 
@@ -20763,9 +20780,8 @@ qemuDomainGetResctrlMonData(virDomainObjPtr dom,
             if (VIR_STRDUP(res->name, virResctrlMonitorGetID(monitor)) < 0)
                 goto error;
 
-            if (virResctrlMonitorGetCacheOccupancy(monitor,
+            if (virResctrlMonitorGetStats(monitor, (const char **)features,
-                                                   &res->stats,
+                                          &res->stats, &res->nstats) < 0)
-                                                   &res->nstats) < 0)
                 goto error;
 
             if (VIR_APPEND_ELEMENT(*resdata, *nresdata, res) < 0)
@@ -20782,7 +20798,8 @@ qemuDomainGetResctrlMonData(virDomainObjPtr dom,
 
 
 static int
-qemuDomainGetStatsCpuCache(virDomainObjPtr dom,
+qemuDomainGetStatsCpuCache(virQEMUDriverPtr driver,
+                           virDomainObjPtr dom,
                            virDomainStatsRecordPtr record,
                            int *maxparams)
 {
@@ -20796,7 +20813,7 @@ qemuDomainGetStatsCpuCache(virDomainObjPtr dom,
     if (!virDomainObjIsActive(dom))
         return 0;
 
-    if (qemuDomainGetResctrlMonData(dom, &resdata, &nresdata,
+    if (qemuDomainGetResctrlMonData(driver, dom, &resdata, &nresdata,
                                     VIR_RESCTRL_MONITOR_TYPE_CACHE) < 0)
         goto cleanup;
 
@@ -20897,7 +20914,7 @@ qemuDomainGetStatsCpuCgroup(virDomainObjPtr dom,
 
 
 static int
-qemuDomainGetStatsCpu(virQEMUDriverPtr driver ATTRIBUTE_UNUSED,
+qemuDomainGetStatsCpu(virQEMUDriverPtr driver,
                       virDomainObjPtr dom,
                       virDomainStatsRecordPtr record,
                       int *maxparams,
@@ -20906,7 +20923,7 @@ qemuDomainGetStatsCpu(virQEMUDriverPtr driver ATTRIBUTE_UNUSED,
     if (qemuDomainGetStatsCpuCgroup(dom, record, maxparams) < 0)
         return -1;
 
-    if (qemuDomainGetStatsCpuCache(dom, record, maxparams) < 0)
+    if (qemuDomainGetStatsCpuCache(driver, dom, record, maxparams) < 0)
         return -1;
 
     return 0;

src/util/virresctrl.c

@@ -2669,8 +2669,7 @@ virResctrlMonitorStatsSorter(const void *a,
  * virResctrlMonitorGetStats
  *
  * @monitor: The monitor that the statistic data will be retrieved from.
- * @resource: The name for resource name. 'llc_occupancy' for cache resource.
+ * @resources: A string list for the monitor feature names.
- * "mbm_total_bytes" and "mbm_local_bytes" for memory bandwidth resource.
  * @stats: Pointer of of virResctrlMonitorStatsPtr array for holding cache or
  * memory bandwidth usage data.
  * @nstats: A size_t pointer to hold the returned array length of @stats
@@ -2679,14 +2678,15 @@ virResctrlMonitorStatsSorter(const void *a,
  *
  * Returns 0 on success, -1 on error.
  */
-static int
+int
 virResctrlMonitorGetStats(virResctrlMonitorPtr monitor,
-                          const char *resource,
+                          const char **resources,
                           virResctrlMonitorStatsPtr **stats,
                           size_t *nstats)
 {
     int rv = -1;
     int ret = -1;
+    size_t i = 0;
     unsigned int val = 0;
     DIR *dirp = NULL;
     char *datapath = NULL;
@@ -2744,21 +2744,23 @@ virResctrlMonitorGetStats(virResctrlMonitorPtr monitor,
         if (virStrToLong_uip(node_id, NULL, 0, &stat->id) < 0)
             goto cleanup;
 
-        rv = virFileReadValueUint(&val, "%s/%s/%s", datapath,
+        for (i = 0; resources[i]; i++) {
-                                  ent->d_name, resource);
+            rv = virFileReadValueUint(&val, "%s/%s/%s", datapath,
-        if (rv == -2) {
+                                      ent->d_name, resources[i]);
-            virReportError(VIR_ERR_INTERNAL_ERROR,
+            if (rv == -2) {
-                           _("File '%s/%s/%s' does not exist."),
+                virReportError(VIR_ERR_INTERNAL_ERROR,
-                           datapath, ent->d_name, resource);
+                               _("File '%s/%s/%s' does not exist."),
+                               datapath, ent->d_name, resources[i]);
+            }
+            if (rv < 0)
+                goto cleanup;
+
+            if (VIR_APPEND_ELEMENT(stat->vals, stat->nvals, val) < 0)
+                goto cleanup;
+
+            if (virStringListAdd(&stat->features, resources[i]) < 0)
+                goto cleanup;
         }
-        if (rv < 0)
-            goto cleanup;
-
-        if (VIR_APPEND_ELEMENT(stat->vals, stat->nvals, val) < 0)
-            goto cleanup;
-
-        if (virStringListAdd(&stat->features, resource) < 0)
-            goto cleanup;
 
         if (VIR_APPEND_ELEMENT(*stats, *nstats, stat) < 0)
             goto cleanup;
@@ -2808,6 +2810,10 @@ virResctrlMonitorGetCacheOccupancy(virResctrlMonitorPtr monitor,
                                    virResctrlMonitorStatsPtr **stats,
                                    size_t *nstats)
 {
-    return virResctrlMonitorGetStats(monitor, "llc_occupancy",
+    int ret = -1;
-                                     stats, nstats);
+    const char *features[2] = {"llc_occupancy", NULL};
+
+    ret = virResctrlMonitorGetStats(monitor, features, stats, nstats);
+
+    return ret;
 }

src/util/virresctrl.h

@@ -234,6 +234,12 @@ virResctrlMonitorSetAlloc(virResctrlMonitorPtr monitor,
 int
 virResctrlMonitorRemove(virResctrlMonitorPtr monitor);
 
+int
+virResctrlMonitorGetStats(virResctrlMonitorPtr monitor,
+                          const char **resources,
+                          virResctrlMonitorStatsPtr **stats,
+                          size_t *nstats);
+
 int
 virResctrlMonitorGetCacheOccupancy(virResctrlMonitorPtr monitor,
                                    virResctrlMonitorStatsPtr **stats,