BUG-650: improve transaction chaining performance

[controller.git] / opendaylight / md-sal / sal-inmemory-datastore / src / main / java / org / opendaylight / controller / md / sal / dom / store / impl / SnapshotBackedWriteTransaction.java

diff --git a/opendaylight/md-sal/sal-inmemory-datastore/src/main/java/org/opendaylight/controller/md/sal/dom/store/impl/SnapshotBackedWriteTransaction.java b/opendaylight/md-sal/sal-inmemory-datastore/src/main/java/org/opendaylight/controller/md/sal/dom/store/impl/SnapshotBackedWriteTransaction.java
index 5f102047684f595a81adc12ddd18866f4fbcd9d7..60a23403b3ac7fce67b01b85295752cdbb2a2e6e 100644 (file)
--- a/opendaylight/md-sal/sal-inmemory-datastore/src/main/java/org/opendaylight/controller/md/sal/dom/store/impl/SnapshotBackedWriteTransaction.java
+++ b/opendaylight/md-sal/sal-inmemory-datastore/src/main/java/org/opendaylight/controller/md/sal/dom/store/impl/SnapshotBackedWriteTransaction.java
@@ -35,8 +35,10 @@ class SnapshotBackedWriteTransaction extends AbstractDOMStoreTransaction impleme
     private static final AtomicReferenceFieldUpdater<SnapshotBackedWriteTransaction, DataTreeModification> TREE_UPDATER =
             AtomicReferenceFieldUpdater.newUpdater(SnapshotBackedWriteTransaction.class, DataTreeModification.class, "mutableTree");
 
-    private volatile TransactionReadyPrototype readyImpl;        // non-null when not ready
-    private volatile DataTreeModification mutableTree;           // non-null when not committed/closed
+    // non-null when not ready
+    private volatile TransactionReadyPrototype readyImpl;
+    // non-null when not committed/closed
+    private volatile DataTreeModification mutableTree;
 
     /**
      * Creates new write-only transaction.
@@ -137,8 +139,11 @@ class SnapshotBackedWriteTransaction extends AbstractDOMStoreTransaction impleme
         checkState(wasReady != null, "Transaction %s is no longer open", getIdentifier());
 
         LOG.debug("Store transaction: {} : Ready", getIdentifier());
-        mutableTree.ready();
-        return wasReady.ready(this);
+
+        final DataTreeModification tree = mutableTree;
+        TREE_UPDATER.lazySet(this, null);
+        tree.ready();
+        return wasReady.transactionReady(this, tree);
     }
 
     @Override
@@ -147,6 +152,7 @@ class SnapshotBackedWriteTransaction extends AbstractDOMStoreTransaction impleme
         if (wasReady != null) {
             LOG.debug("Store transaction: {} : Closed", getIdentifier());
             TREE_UPDATER.lazySet(this, null);
+            wasReady.transactionAborted(this);
         } else {
             LOG.debug("Store transaction: {} : Closed after submit", getIdentifier());
         }
@@ -157,15 +163,6 @@ class SnapshotBackedWriteTransaction extends AbstractDOMStoreTransaction impleme
         return toStringHelper.add("ready", readyImpl == null);
     }
 
-    // FIXME: used by chaining on, which really wants an mutated view with a precondition
-    final boolean isReady() {
-        return readyImpl == null;
-    }
-
-    protected DataTreeModification getMutatedView() {
-        return mutableTree;
-    }
-
     /**
      * Prototype implementation of
      * {@link #ready(org.opendaylight.controller.md.sal.dom.store.impl.SnapshotBackedWriteTransaction)}
@@ -175,8 +172,15 @@ class SnapshotBackedWriteTransaction extends AbstractDOMStoreTransaction impleme
      * providing underlying logic for applying implementation.
      *
      */
-    // FIXME: needs access to local stuff, so make it an abstract class
-    public static interface TransactionReadyPrototype {
+    abstract static class TransactionReadyPrototype {
+        /**
+         * Called when a transaction is closed without being readied. This is not invoked for
+         * transactions which are ready.
+         *
+         * @param tx Transaction which got aborted.
+         */
+        protected abstract void transactionAborted(final SnapshotBackedWriteTransaction tx);
+
         /**
          * Returns a commit coordinator associated with supplied transactions.
          *
@@ -184,8 +188,10 @@ class SnapshotBackedWriteTransaction extends AbstractDOMStoreTransaction impleme
          *
          * @param tx
          *            Transaction on which ready was invoked.
+         * @param tree
+         *            Modified data tree which has been constructed.
          * @return DOMStoreThreePhaseCommitCohort associated with transaction
          */
-        DOMStoreThreePhaseCommitCohort ready(SnapshotBackedWriteTransaction tx);
+        protected abstract DOMStoreThreePhaseCommitCohort transactionReady(SnapshotBackedWriteTransaction tx, DataTreeModification tree);
     }
 }
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