Revert "SERVER-37313 Secondary foreground index build should take Database X rather than Global X lock"

This reverts commit 3aebbb51ed5fe82601f601916251c5f892a59467.

2 files changed, 5 insertions, 13 deletions

diff --git a/src/mongo/db/repl/oplog.cpp b/src/mongo/db/repl/oplog.cpp
index 94477d111d8..2ad84d776e9 100644
--- a/src/mongo/db/repl/oplog.cpp
+++ b/src/mongo/db/repl/oplog.cpp
@@ -231,11 +231,6 @@ void createIndexForApplyOps(OperationContext* opCtx,
                             const NamespaceString& indexNss,
                             IncrementOpsAppliedStatsFn incrementOpsAppliedStats,
                             OplogApplication::Mode mode) {
-    // Lock the database if it's not locked.
-    boost::optional<Lock::DBLock> dbLock;
-    if (!opCtx->lockState()->isDbLockedForMode(indexNss.db(), MODE_X)) {
-        dbLock.emplace(opCtx, indexNss.db(), MODE_X);
-    }
     // Check if collection exists.
     Database* db = DatabaseHolder::getDatabaseHolder().get(opCtx, indexNss.ns());
     auto indexCollection = db ? db->getCollection(opCtx, indexNss) : nullptr;
@@ -1530,7 +1525,6 @@ Status applyCommand_inlock(OperationContext* opCtx,
         return {ErrorCodes::InvalidNamespace, "invalid ns: " + std::string(nss.ns())};
     }
     {
-        Lock::DBLock lock(opCtx, nss.db(), MODE_IS);
         Database* db = DatabaseHolder::getDatabaseHolder().get(opCtx, nss.ns());
         if (db && !db->getCollection(opCtx, nss) && db->getViewCatalog()->lookup(opCtx, nss.ns())) {
             return {ErrorCodes::CommandNotSupportedOnView,
@@ -1555,6 +1549,10 @@ Status applyCommand_inlock(OperationContext* opCtx,
                                     << redact(op));
     }
 
+    // Applying commands in repl is done under Global W-lock, so it is safe to not
+    // perform the current DB checks after reacquiring the lock.
+    invariant(opCtx->lockState()->isW());
+
     // Parse optime from oplog entry unless we are applying this command in standalone or on a
     // primary (replicated writes enabled).
     OpTime opTime;
diff --git a/src/mongo/db/repl/sync_tail.cpp b/src/mongo/db/repl/sync_tail.cpp
index b611f8b8305..0356a80e1d9 100644
--- a/src/mongo/db/repl/sync_tail.cpp
+++ b/src/mongo/db/repl/sync_tail.cpp
@@ -387,13 +387,7 @@ Status SyncTail::syncApply(OperationContext* opCtx,
         return writeConflictRetry(opCtx, "syncApply_command", nss.ns(), [&] {
             // a command may need a global write lock. so we will conservatively go
             // ahead and grab one here. suboptimal. :-(
-            boost::optional<Lock::GlobalWrite> globalWriteLock;
-
-            const StringData commandName(op["o"].embeddedObject().firstElementFieldName());
-            // SERVER-37313: createIndex does not need to take the Global X lock.
-            if (commandName != "createIndexes") {
-                globalWriteLock.emplace(opCtx);
-            }
+            Lock::GlobalWrite globalWriteLock(opCtx);
 
             // special case apply for commands to avoid implicit database creation
             Status status = applyCommand_inlock(opCtx, op, oplogApplicationMode);