HBASE-952 Deadlock in HRegion.batchUpdate

git-svn-id: https://svn.apache.org/repos/asf/hadoop/hbase/trunk@707457 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -40,6 +40,7 @@ Release 0.19.0 - Unreleased
    HBASE-946   Row with 55k deletes timesout scanner lease
    HBASE-950   HTable.commit no longer works with existing RowLocks though it's still in API
    HBASE-728   Support for HLog appends
+   HBASE-952   Deadlock in HRegion.batchUpdate
 
   IMPROVEMENTS
    HBASE-901   Add a limit to key length, check key and value length on client side

src/java/org/apache/hadoop/hbase/regionserver/HRegion.java

@@ -1125,21 +1125,17 @@ public class HRegion implements HConstants {
    *
    * @param row
    * @param column
-   * @param timestamp
-   * @param numVersions
+   * @param ts
+   * @param nv
    * @return array of values one element per version that matches the timestamp, 
    * or null if there are no matches.
    * @throws IOException
    */
-  public Cell[] get(byte [] row, byte [] column, long timestamp,
-    int numVersions) 
+  public Cell[] get(final byte[] row, final byte[] column, final long ts,
+      final int nv) 
   throws IOException {
-    if (timestamp == -1) {
-      timestamp = Long.MAX_VALUE;
-    }
-    if (numVersions == -1) {
-      numVersions = 1;
-    }
+    long timestamp = ts == -1 ? HConstants.LATEST_TIMESTAMP : ts;
+    int numVersions = nv == -1 ? 1 : nv;
 
     splitsAndClosesLock.readLock().lock();
     try {
@@ -1354,20 +1350,15 @@ public class HRegion implements HConstants {
   //////////////////////////////////////////////////////////////////////////////
   
   /**
-   * Batch update many rows and take splitsAndClosesLock so we don't get 
-   * blocked while updating.
+   * Batch update many rows
    * @param bus 
+   * @param locks
+   * @throws IOException
    */
-  public void batchUpdate(BatchUpdate[] bus, Integer[] locks)
-      throws IOException {
-    splitsAndClosesLock.readLock().lock();
-    try {
+  public void batchUpdate(BatchUpdate[] bus, Integer[] locks) throws IOException {
     for (int i = 0; i < bus.length; i++) {
       batchUpdate(bus[i], locks[i]);
     }
-    } finally {
-      splitsAndClosesLock.readLock().unlock();
-    }
   }
   
   /**
@@ -1413,6 +1404,8 @@ public class HRegion implements HConstants {
     // will be extremely rare; we'll deal with it when it happens.
     checkResources();
 
+    splitsAndClosesLock.readLock().lock();
+    try {
       // We obtain a per-row lock, so other clients will block while one client
       // performs an update. The read lock is released by the client calling
       // #commit or #abort or if the HRegionServer lease on the lock expires.
@@ -1468,6 +1461,9 @@ public class HRegion implements HConstants {
       } finally {
         if(lockid == null) releaseRowLock(lid);
       }
+    } finally {
+      splitsAndClosesLock.readLock().unlock();
+    }
   }
 
   /*
@@ -1539,8 +1535,8 @@ public class HRegion implements HConstants {
    * @param lockid Row lock
    * @throws IOException
    */
-  public void deleteAll(final byte [] row, final long ts,
-      final Integer lockid)
+  @SuppressWarnings("unchecked")
+  public void deleteAll(final byte [] row, final long ts, final Integer lockid)
   throws IOException {
     checkReadOnly();
     Integer lid = getLock(lockid, row);
@@ -1571,6 +1567,7 @@ public class HRegion implements HConstants {
    * @param lockid Row lock
    * @throws IOException
    */
+  @SuppressWarnings("unchecked")
   public void deleteFamily(byte [] row, byte [] family, long timestamp,
       final Integer lockid)
   throws IOException{
@@ -1606,6 +1603,7 @@ public class HRegion implements HConstants {
    * {@link HConstants#ALL_VERSIONS} to delete all.
    * @throws IOException
    */
+  @SuppressWarnings("unchecked")
   private void deleteMultiple(final byte [] row, final byte [] column,
       final long ts, final int versions)
   throws IOException {
@@ -1643,6 +1641,7 @@ public class HRegion implements HConstants {
    * @param val Value to enter into cell
    * @throws IOException
    */
+  @SuppressWarnings("unchecked")
   private void localput(final Integer lockid, final HStoreKey key,
       final byte [] val)
   throws IOException {
@@ -1870,9 +1869,8 @@ public class HRegion implements HConstants {
     synchronized (locksToRows) {
       if(locksToRows.containsKey(lockid)) {
         return true;
-      } else {
-        return false;
       }
+      return false;
     }
   }
   
@@ -2219,6 +2217,7 @@ public class HRegion implements HConstants {
    *
    * @throws IOException
    */
+  @SuppressWarnings("unchecked")
   public static void addRegionToMETA(HRegion meta, HRegion r) 
   throws IOException {
     meta.checkResources();