SERVER-7443 - make sure writeback ids are in order

Conflicts:
	src/mongo/s/d_writeback.h

3 files changed, 18 insertions, 28 deletions

diff --git a/src/mongo/s/d_logic.cpp b/src/mongo/s/d_logic.cpp
index dcf66033428..c58ed173968 100644
--- a/src/mongo/s/d_logic.cpp
+++ b/src/mongo/s/d_logic.cpp
@@ -103,9 +103,6 @@ namespace mongo {
 
         uassert( 9517 , "writeback" , ( d.reservedField() & Reserved_FromWriteback ) == 0 );
 
-        OID writebackID;
-        writebackID.initSequential();
-
         const OID& clientID = ShardedConnectionInfo::get(false)->getID();
         massert( 10422 ,  "write with bad shard config and no server id!" , clientID.isSet() );
 
@@ -121,7 +118,6 @@ namespace mongo {
         BSONObjBuilder b;
         b.appendBool( "writeBack" , true );
         b.append( "ns" , ns );
-        b.append( "id" , writebackID );
         b.append( "connectionId" , cc().getConnectionId() );
         b.append( "instanceIdent" , prettyHostName() );
         wanted.addToBSON( b );
@@ -130,15 +126,10 @@ namespace mongo {
         b.appendBinData( "msg" , m.header()->len , bdtCustom , (char*)(m.singleData()) );
         LOG(2) << "writing back msg with len: " << m.header()->len << " op: " << m.operation() << endl;
 
-        // Convert to new BSONObj here just to be safe
-        BSONObj wbObj = b.obj();
+        OID writebackID = writeBackManager.queueWriteBack( clientID.str() , b );
 
-        // Don't register the writeback until immediately before we queue it -
-        // after this line, mongos will wait for an hour if we don't queue correctly
         lastError.getSafe()->writeback( writebackID );
 
-        writeBackManager.queueWriteBack( clientID.str() , wbObj );
-
         return true;
     }
 
diff --git a/src/mongo/s/d_writeback.cpp b/src/mongo/s/d_writeback.cpp
index 0278e40f712..441de1a0d65 100644
--- a/src/mongo/s/d_writeback.cpp
+++ b/src/mongo/s/d_writeback.cpp
@@ -42,21 +42,18 @@ namespace mongo {
     WriteBackManager::~WriteBackManager() {
     }
 
-    void WriteBackManager::queueWriteBack( const string& remote , const BSONObj& o ) {
-        static mongo::mutex xxx( "WriteBackManager::queueWriteBack tmp" );
-        static OID lastOID;
-
-        scoped_lock lk( xxx );
-        const BSONElement& e = o["id"];
-
-        if ( lastOID.isSet() ) {
-            if ( e.OID() < lastOID ) {
-                log() << "this could fail" << endl;
-                printStackTrace();
-            }
-        }
-        lastOID = e.OID();
-        getWritebackQueue( remote )->queue.push( o );
+    OID WriteBackManager::queueWriteBack( const string& remote , BSONObjBuilder& b ) {
+        static mongo::mutex writebackIDOrdering( "WriteBackManager::queueWriteBack id ordering" );
+        
+        scoped_lock lk( writebackIDOrdering );
+
+        OID writebackID;
+        writebackID.initSequential();
+        b.append( "id", writebackID );
+        
+        getWritebackQueue( remote )->queue.push( b.obj() );
+
+        return writebackID;
     }
 
     shared_ptr<WriteBackManager::QueueInfo> WriteBackManager::getWritebackQueue( const string& remote ) {
diff --git a/src/mongo/s/d_writeback.h b/src/mongo/s/d_writeback.h
index fc5d9c19f29..38ce386515b 100644
--- a/src/mongo/s/d_writeback.h
+++ b/src/mongo/s/d_writeback.h
@@ -56,10 +56,12 @@ namespace mongo {
          * @param remote server ID this operation came from
          * @param op the operation itself
          *
-         * Enqueues opeartion 'op' in server 'remote's queue. The operation will be written back to
-         * remote at a later stager.
+         * Enqueues operation 'op' in server 'remote's queue. The operation will be written back to
+         * remote at a later stage.
+         *
+         * @return the writebackId generated
          */
-        void queueWriteBack( const string& remote , const BSONObj& op );
+        OID queueWriteBack( const string& remote , BSONObjBuilder& opBuilder );
 
         /*
          * @param remote server ID