1 files changed, 22 insertions, 13 deletions

diff --git a/src/mongo/db/catalog/database.cpp b/src/mongo/db/catalog/database.cpp
index 9b68549f295..13b4b7faa01 100644
--- a/src/mongo/db/catalog/database.cpp
+++ b/src/mongo/db/catalog/database.cpp
@@ -315,14 +315,8 @@ void Database::getStats(OperationContext* opCtx, BSONObjBuilder* output, double
 }
 
 Status Database::dropCollection(OperationContext* txn, StringData fullns) {
-    invariant(txn->lockState()->isDbLockedForMode(name(), MODE_X));
-
-    LOG(1) << "dropCollection: " << fullns << endl;
-    massertNamespaceNotIndex(fullns, "dropCollection");
-
-    Collection* collection = getCollection(fullns);
-    if (!collection) {
-        // collection doesn't exist
+    if (!getCollection(fullns)) {
+        // Collection doesn't exist so don't bother validating if it can be dropped.
         return Status::OK();
     }
 
@@ -341,9 +335,24 @@ Status Database::dropCollection(OperationContext* txn, StringData fullns) {
         }
     }
 
+    return dropCollectionEvenIfSystem(txn, nss);
+}
+
+Status Database::dropCollectionEvenIfSystem(OperationContext* txn, const NamespaceString& fullns) {
+    invariant(txn->lockState()->isDbLockedForMode(name(), MODE_X));
+
+    LOG(1) << "dropCollection: " << fullns;
+
+    Collection* collection = getCollection(fullns);
+    if (!collection) {
+        return Status::OK();  // Post condition already met.
+    }
+
+    massertNamespaceNotIndex(fullns.toString(), "dropCollection");
+
     BackgroundOperation::assertNoBgOpInProgForNs(fullns);
 
-    audit::logDropCollection(&cc(), fullns);
+    audit::logDropCollection(&cc(), fullns.toString());
 
     Status s = collection->getIndexCatalog()->dropAllIndexes(txn, true);
     if (!s.isOK()) {
@@ -355,13 +364,13 @@ Status Database::dropCollection(OperationContext* txn, StringData fullns) {
     verify(collection->_details->getTotalIndexCount(txn) == 0);
     LOG(1) << "\t dropIndexes done" << endl;
 
-    Top::get(txn->getClient()->getServiceContext()).collectionDropped(fullns);
+    Top::get(txn->getClient()->getServiceContext()).collectionDropped(fullns.toString());
 
     // We want to destroy the Collection object before telling the StorageEngine to destroy the
     // RecordStore.
-    _clearCollectionCache(txn, fullns, "collection dropped");
+    _clearCollectionCache(txn, fullns.toString(), "collection dropped");
 
-    s = _dbEntry->dropCollection(txn, fullns);
+    s = _dbEntry->dropCollection(txn, fullns.toString());
 
     if (!s.isOK())
         return s;
@@ -378,7 +387,7 @@ Status Database::dropCollection(OperationContext* txn, StringData fullns) {
         }
     }
 
-    getGlobalServiceContext()->getOpObserver()->onDropCollection(txn, nss);
+    getGlobalServiceContext()->getOpObserver()->onDropCollection(txn, fullns);
     return Status::OK();
 }