3 files changed, 38 insertions, 1 deletions

diff --git a/src/mongo/db/mongod_main.cpp b/src/mongo/db/mongod_main.cpp
index 2fd444f818a..30b24b89db0 100644
--- a/src/mongo/db/mongod_main.cpp
+++ b/src/mongo/db/mongod_main.cpp
@@ -1315,6 +1315,10 @@ void shutdownTask(const ShutdownTaskArgs& shutdownArgs) {
         sr->shutdown();
     }
 
+    if (ShardingState::get(serviceContext)->enabled()) {
+        TransactionCoordinatorService::get(serviceContext)->shutdown();
+    }
+
     // Validator shutdown must be called after setKillAllOperations is called. Otherwise, this can
     // deadlock.
     if (auto validator = LogicalTimeValidator::get(serviceContext)) {
diff --git a/src/mongo/db/s/transaction_coordinator_service.cpp b/src/mongo/db/s/transaction_coordinator_service.cpp
index 39f0ef4bef7..349db0ac079 100644
--- a/src/mongo/db/s/transaction_coordinator_service.cpp
+++ b/src/mongo/db/s/transaction_coordinator_service.cpp
@@ -179,6 +179,10 @@ void TransactionCoordinatorService::onStepUp(OperationContext* opCtx,
     joinPreviousRound();
 
     stdx::lock_guard<Latch> lg(_mutex);
+    if (_isShuttingDown) {
+        return;
+    }
+
     invariant(!_catalogAndScheduler);
     _catalogAndScheduler = std::make_shared<CatalogAndScheduler>(opCtx->getServiceContext());
 
@@ -264,12 +268,25 @@ void TransactionCoordinatorService::onStepDown() {
     _catalogAndSchedulerToCleanup->onStepDown();
 }
 
+void TransactionCoordinatorService::shutdown() {
+    {
+        stdx::lock_guard<Latch> lg(_mutex);
+        _isShuttingDown = true;
+    }
+
+    onStepDown();
+    joinPreviousRound();
+}
+
 void TransactionCoordinatorService::onShardingInitialization(OperationContext* opCtx,
                                                              bool isPrimary) {
     if (!isPrimary)
         return;
 
     stdx::lock_guard<Latch> lg(_mutex);
+    if (_isShuttingDown) {
+        return;
+    }
 
     invariant(!_catalogAndScheduler);
     _catalogAndScheduler = std::make_shared<CatalogAndScheduler>(opCtx->getServiceContext());
@@ -289,18 +306,26 @@ TransactionCoordinatorService::_getCatalogAndScheduler(OperationContext* opCtx)
 }
 
 void TransactionCoordinatorService::joinPreviousRound() {
+    stdx::unique_lock<Latch> ul(_mutex);
+
     // onStepDown must have been called
     invariant(!_catalogAndScheduler);
 
     if (!_catalogAndSchedulerToCleanup)
         return;
 
+    auto schedulerToCleanup = _catalogAndSchedulerToCleanup;
+
+    ul.unlock();
+
     LOGV2(22454, "Waiting for coordinator tasks from previous term to complete");
 
     // Block until all coordinators scheduled the previous time the service was primary to have
     // drained. Because the scheduler was interrupted, it should be extremely rare for there to be
     // any coordinators left, so if this actually causes blocking, it would most likely be a bug.
-    _catalogAndSchedulerToCleanup->join();
+    schedulerToCleanup->join();
+
+    ul.lock();
     _catalogAndSchedulerToCleanup.reset();
 }
 
diff --git a/src/mongo/db/s/transaction_coordinator_service.h b/src/mongo/db/s/transaction_coordinator_service.h
index f50a511a8a3..4f931b75383 100644
--- a/src/mongo/db/s/transaction_coordinator_service.h
+++ b/src/mongo/db/s/transaction_coordinator_service.h
@@ -103,6 +103,11 @@ public:
     void onStepDown();
 
     /**
+     * Shuts down this service. This will no longer be usable once shutdown is called.
+     */
+    void shutdown();
+
+    /**
      * Called when an already established replica set is added as a shard to a cluster. Ensures that
      * the TransactionCoordinator service is started up if the replica set is currently primary.
      */
@@ -151,6 +156,9 @@ private:
     // The catalog + scheduler instantiated at the last step-up attempt. When nullptr, it means
     // onStepUp has not been called yet after the last stepDown (or construction).
     std::shared_ptr<CatalogAndScheduler> _catalogAndScheduler;
+
+    // Sets to false once shutdown was called at least once.
+    bool _isShuttingDown{false};
 };
 
 }  // namespace mongo