SERVER-43019 remove unreachable code from IndexBuildsCoordinator and rename function

The code for _shuttingDown was made unreachable by commit c72617a.

Author: benety

src/mongo/db/index_builds_coordinator.cpp

@@ -255,9 +255,8 @@ Future<void> IndexBuildsCoordinator::joinIndexBuilds(const NamespaceString& nss,
     return std::move(pf.future);
 }
 
-void IndexBuildsCoordinator::interruptAllIndexBuildsForShutdown(const std::string& reason) {
+void IndexBuildsCoordinator::waitForAllIndexBuildsToStopForShutdown() {
     stdx::unique_lock<stdx::mutex> lk(_mutex);
-    _shuttingDown = true;
 
     // All index builds should have been signaled to stop via the ServiceContext.
 
@@ -828,11 +827,6 @@ void IndexBuildsCoordinator::_runIndexBuildInner(OperationContext* opCtx,
 
         // Failed index builds should abort secondary oplog application.
         if (replSetAndNotPrimary) {
-            stdx::unique_lock<stdx::mutex> lk(_mutex);
-            if (_shuttingDown) {
-                // Allow shutdown with success exit status, despite interrupted index builds.
-                return;
-            }
             fassert(51101,
                     status.withContext(str::stream() << "Index build: " << replState->buildUUID
                                                      << "; Database: " << replState->dbName));

src/mongo/db/index_builds_coordinator.h

@@ -148,14 +148,14 @@ class IndexBuildsCoordinator {
                                     const UUID& buildUUID) = 0;
 
     /**
-     * Signals all the index builds to stop and then waits for them to finish. Leaves the index
-     * builds in a recoverable state.
+     * Waits for all index builds to stop after they have been interrupted during shutdown.
+     * Leaves the index builds in a recoverable state.
      *
      * This should only be called when certain the server will not start any new index builds --
      * i.e. when the server is not accepting user requests and no internal operations are
      * concurrently starting new index builds.
      */
-    void interruptAllIndexBuildsForShutdown(const std::string& reason);
+    void waitForAllIndexBuildsToStopForShutdown();
 
     /**
      * Signals all of the index builds on the specified collection to abort and then waits until the
@@ -442,7 +442,6 @@ class IndexBuildsCoordinator {
     IndexBuildsManager _indexBuildsManager;
 
     bool _sleepForTest = false;
-    bool _shuttingDown = false;
 };
 
 /**

src/mongo/db/index_builds_coordinator_mongod.cpp

@@ -80,8 +80,8 @@ void IndexBuildsCoordinatorMongod::shutdown() {
     // Stop new scheduling.
     _threadPool.shutdown();
 
-    // Signal active builds to stop and wait for them to stop.
-    interruptAllIndexBuildsForShutdown("Index build interrupted due to shutdown.");
+    // Wait for all active builds to stop.
+    waitForAllIndexBuildsToStopForShutdown();
 
     // Wait for active threads to finish.
     _threadPool.join();