quota: realtime usage update for metrics, logical/physical sizes, and data points

Without this patch, it is possible for some namespaces to have a window of 1-3 `carbonserver.quota-usage-report-frequency`
to conduct quota enforcement penetration.

However, this patch can still only enforce it for existing namespaces that has already being annotated by
*trieIndex.applyQuotas. For new namespaces, the possibility still exists. A separate patch of approach is needed.

Author: bom-d-van

carbonserver/trie.go

@@ -538,6 +538,7 @@ func (ti *trieIndex) insert(path string, logicalSize, physicalSize, dataPoints,
 	var start, nlen int
 	var sn, newn *trieNode
 	var cur = ti.root
+	var dirMetas = make([]trieMeta, 0, 32)
 outer:
 	// why len(path)+1: make sure the last node is also processed in the loop
 	for i := 0; i < len(path)+1; i++ {
@@ -649,6 +650,10 @@ outer:
 			if child.dir() {
 				cur = child
 				cur.gen = ti.root.gen
+
+				if child.meta != nil {
+					dirMetas = append(dirMetas, child.meta)
+				}
 				continue outer
 			}
 		}
@@ -720,7 +725,20 @@ outer:
 		cur.addChild(child)
 		cur = child
 
+		// TODO: need to support realtime and concurrent index?
 		ti.fileCount++
+
+		for _, dm := range dirMetas {
+			meta, ok := dm.(*dirMeta)
+			if !ok || meta.usage == nil {
+				continue
+			}
+
+			atomic.AddInt64(&meta.usage.Metrics, 1)
+			atomic.AddInt64(&meta.usage.LogicalSize, logicalSize)
+			atomic.AddInt64(&meta.usage.PhysicalSize, physicalSize)
+			atomic.AddInt64(&meta.usage.DataPoints, dataPoints)
+		}
 	}
 
 	return cur, nil