Allow storage plugins to get storage/volume stats without sending commands to hosts (apache#4826)

* Allow storage plugins to use storage/volume stats

Allow the rest of the storage plugins, not only ScaleIO to implement and
use the storage/volume statistics directly instead of sending cmd to
hosts

* Get the store driver from pool instead of passing it as argument

required change from code review to pick the store driver from pool not
to pass it as argument

Author: slavkap

server/src/main/java/com/cloud/storage/StorageManagerImpl.java

@@ -465,10 +465,13 @@ public Answer sendToPool(StoragePool pool, long[] hostIdsToTryFirst, Command cmd
 
     @Override
     public Answer sendToPool(StoragePool pool, Command cmd) throws StorageUnavailableException {
-        if (cmd instanceof GetStorageStatsCommand && pool.getPoolType() == StoragePoolType.PowerFlex) {
-            // Get stats from the pool directly instead of sending cmd to host
-            // Added support for ScaleIO/PowerFlex pool only
-            return getStoragePoolStats(pool, (GetStorageStatsCommand) cmd);
+        if (cmd instanceof GetStorageStatsCommand) {
+            DataStoreProvider storeProvider = _dataStoreProviderMgr.getDataStoreProvider(pool.getStorageProviderName());
+            DataStoreDriver storeDriver = storeProvider.getDataStoreDriver();
+            if (storeDriver instanceof PrimaryDataStoreDriver && ((PrimaryDataStoreDriver)storeDriver).canProvideStorageStats()) {
+                // Get stats from the pool directly instead of sending cmd to host
+                return getStoragePoolStats(pool, (GetStorageStatsCommand) cmd);
+            }
         }
 
         Answer[] answers = sendToPool(pool, new Commands(cmd));
@@ -479,49 +482,40 @@ public Answer sendToPool(StoragePool pool, Command cmd) throws StorageUnavailabl
     }
 
     private GetStorageStatsAnswer getStoragePoolStats(StoragePool pool, GetStorageStatsCommand cmd) {
-        DataStoreProvider storeProvider = _dataStoreProviderMgr.getDataStoreProvider(pool.getStorageProviderName());
-        DataStoreDriver storeDriver = storeProvider.getDataStoreDriver();
         GetStorageStatsAnswer answer = null;
 
-        if (storeDriver instanceof PrimaryDataStoreDriver && ((PrimaryDataStoreDriver)storeDriver).canProvideStorageStats()) {
-            PrimaryDataStoreDriver primaryStoreDriver = (PrimaryDataStoreDriver)storeDriver;
-            Pair<Long, Long> storageStats = primaryStoreDriver.getStorageStats(pool);
-            if (storageStats == null) {
-                answer = new GetStorageStatsAnswer((GetStorageStatsCommand) cmd, "Failed to get storage stats for pool: " + pool.getId());
-            } else {
-                answer = new GetStorageStatsAnswer((GetStorageStatsCommand) cmd, storageStats.first(), storageStats.second());
-            }
+        DataStoreProvider storeProvider = _dataStoreProviderMgr.getDataStoreProvider(pool.getStorageProviderName());
+        DataStoreDriver storeDriver = storeProvider.getDataStoreDriver();
+        PrimaryDataStoreDriver primaryStoreDriver = (PrimaryDataStoreDriver) storeDriver;
+        Pair<Long, Long> storageStats = primaryStoreDriver.getStorageStats(pool);
+        if (storageStats == null) {
+            answer = new GetStorageStatsAnswer((GetStorageStatsCommand) cmd, "Failed to get storage stats for pool: " + pool.getId());
+        } else {
+            answer = new GetStorageStatsAnswer((GetStorageStatsCommand) cmd, storageStats.first(), storageStats.second());
         }
 
         return answer;
     }
 
     @Override
     public Answer getVolumeStats(StoragePool pool, Command cmd) {
-        if (!(cmd instanceof GetVolumeStatsCommand)) {
-            return null;
-        }
-
         DataStoreProvider storeProvider = _dataStoreProviderMgr.getDataStoreProvider(pool.getStorageProviderName());
         DataStoreDriver storeDriver = storeProvider.getDataStoreDriver();
-
-        if (storeDriver instanceof PrimaryDataStoreDriver && ((PrimaryDataStoreDriver)storeDriver).canProvideVolumeStats()) {
-            PrimaryDataStoreDriver primaryStoreDriver = (PrimaryDataStoreDriver)storeDriver;
-            HashMap<String, VolumeStatsEntry> statEntry = new HashMap<String, VolumeStatsEntry>();
-            GetVolumeStatsCommand getVolumeStatsCommand = (GetVolumeStatsCommand) cmd;
-            for (String volumeUuid : getVolumeStatsCommand.getVolumeUuids()) {
-                Pair<Long, Long> volumeStats = primaryStoreDriver.getVolumeStats(pool, volumeUuid);
-                if (volumeStats == null) {
-                    return new GetVolumeStatsAnswer(getVolumeStatsCommand, "Failed to get stats for volume: " + volumeUuid, null);
-                } else {
-                    VolumeStatsEntry volumeStatsEntry = new VolumeStatsEntry(volumeUuid, volumeStats.first(), volumeStats.second());
-                    statEntry.put(volumeUuid, volumeStatsEntry);
-                }
+        PrimaryDataStoreDriver primaryStoreDriver = (PrimaryDataStoreDriver) storeDriver;
+        HashMap<String, VolumeStatsEntry> statEntry = new HashMap<String, VolumeStatsEntry>();
+        GetVolumeStatsCommand getVolumeStatsCommand = (GetVolumeStatsCommand) cmd;
+        for (String volumeUuid : getVolumeStatsCommand.getVolumeUuids()) {
+            Pair<Long, Long> volumeStats = primaryStoreDriver.getVolumeStats(pool, volumeUuid);
+            if (volumeStats == null) {
+                return new GetVolumeStatsAnswer(getVolumeStatsCommand, "Failed to get stats for volume: " + volumeUuid,
+                        null);
+            } else {
+                VolumeStatsEntry volumeStatsEntry = new VolumeStatsEntry(volumeUuid, volumeStats.first(),
+                        volumeStats.second());
+                statEntry.put(volumeUuid, volumeStatsEntry);
             }
-            return new GetVolumeStatsAnswer(getVolumeStatsCommand, "", statEntry);
         }
-
-        return null;
+        return new GetVolumeStatsAnswer(getVolumeStatsCommand, "", statEntry);
     }
 
     public Long chooseHostForStoragePool(StoragePoolVO poolVO, List<Long> avoidHosts, boolean sendToVmResidesOn, Long vmId) {

server/src/main/java/com/cloud/vm/UserVmManagerImpl.java

@@ -95,8 +95,12 @@
 import org.apache.cloudstack.engine.orchestration.service.VolumeOrchestrationService;
 import org.apache.cloudstack.engine.service.api.OrchestrationService;
 import org.apache.cloudstack.engine.subsystem.api.storage.DataStore;
+import org.apache.cloudstack.engine.subsystem.api.storage.DataStoreDriver;
 import org.apache.cloudstack.engine.subsystem.api.storage.DataStoreManager;
+import org.apache.cloudstack.engine.subsystem.api.storage.DataStoreProvider;
+import org.apache.cloudstack.engine.subsystem.api.storage.DataStoreProviderManager;
 import org.apache.cloudstack.engine.subsystem.api.storage.PrimaryDataStore;
+import org.apache.cloudstack.engine.subsystem.api.storage.PrimaryDataStoreDriver;
 import org.apache.cloudstack.engine.subsystem.api.storage.VolumeDataFactory;
 import org.apache.cloudstack.engine.subsystem.api.storage.VolumeInfo;
 import org.apache.cloudstack.engine.subsystem.api.storage.VolumeService;
@@ -532,6 +536,7 @@ public class UserVmManagerImpl extends ManagerBase implements UserVmManager, Vir
     @Inject
     private UserVmDeployAsIsDetailsDao userVmDeployAsIsDetailsDao;
     @Inject
+    private DataStoreProviderManager _dataStoreProviderMgr;
     private StorageManager storageManager;
     @Inject
     private ServiceOfferingJoinDao serviceOfferingJoinDao;
@@ -2108,9 +2113,12 @@ public HashMap<String, VolumeStatsEntry> getVolumeStatistics(long clusterId, Str
                 GetVolumeStatsCommand cmd = new GetVolumeStatsCommand(poolType, poolUuid, volumeLocators);
                 Answer answer = null;
 
-                if (poolType == StoragePoolType.PowerFlex) {
+                DataStoreProvider storeProvider = _dataStoreProviderMgr
+                        .getDataStoreProvider(storagePool.getStorageProviderName());
+                DataStoreDriver storeDriver = storeProvider.getDataStoreDriver();
+
+                if (storeDriver instanceof PrimaryDataStoreDriver && ((PrimaryDataStoreDriver) storeDriver).canProvideVolumeStats()) {
                     // Get volume stats from the pool directly instead of sending cmd to host
-                    // Added support for ScaleIO/PowerFlex pool only
                     answer = storageManager.getVolumeStats(storagePool, cmd);
                 } else {
                     if (timeout > 0) {