HBASE-22904 NPE occurs when RS send space quota usage report during HMaster init (apache#529)

* NPE occurs when RS send space quota usage report during HMaster init

* Added the debug log

 Signed-off-by: Sakthi <sakthi@apache.org>
 Signed-off-by: stack <stack@apache.org>

Author: Pankaj

hbase-server/src/main/java/org/apache/hadoop/hbase/master/MasterRpcServices.java

@@ -2302,10 +2302,15 @@ public RegionSpaceUseReportResponse reportRegionSpaceUse(RpcController controlle
         return RegionSpaceUseReportResponse.newBuilder().build();
       }
       MasterQuotaManager quotaManager = this.master.getMasterQuotaManager();
-      final long now = EnvironmentEdgeManager.currentTime();
-      for (RegionSpaceUse report : request.getSpaceUseList()) {
-        quotaManager.addRegionSize(ProtobufUtil.toRegionInfo(
-            report.getRegionInfo()), report.getRegionSize(), now);
+      if (quotaManager != null) {
+        final long now = EnvironmentEdgeManager.currentTime();
+        for (RegionSpaceUse report : request.getSpaceUseList()) {
+          quotaManager.addRegionSize(ProtobufUtil.toRegionInfo(report.getRegionInfo()),
+            report.getRegionSize(), now);
+        }
+      } else {
+        LOG.debug(
+          "Received region space usage report but HMaster is not ready to process it, skipping");
       }
       return RegionSpaceUseReportResponse.newBuilder().build();
     } catch (Exception e) {
@@ -2340,6 +2345,9 @@ public GetSpaceQuotaRegionSizesResponse getSpaceQuotaRegionSizes(
               .setSize(tableSize.getValue()).build());
         }
         return builder.build();
+      } else {
+        LOG.debug(
+          "Received space quota region size report but HMaster is not ready to process it, skipping");
       }
       return builder.build();
     } catch (Exception e) {