1 files changed, 26 insertions, 22 deletions

diff --git a/src/mongo/client/replica_set_monitor_manager.cpp b/src/mongo/client/replica_set_monitor_manager.cpp
index c440f5b0b8f..52db50f277c 100644
--- a/src/mongo/client/replica_set_monitor_manager.cpp
+++ b/src/mongo/client/replica_set_monitor_manager.cpp
@@ -72,8 +72,8 @@ const auto getGlobalRSMMonitorManager =
 
 Status ReplicaSetMonitorManagerNetworkConnectionHook::validateHost(
     const HostAndPort& remoteHost,
-    const BSONObj& helloRequest,
-    const executor::RemoteCommandResponse& helloReply) {
+    const BSONObj& isMasterRequest,
+    const executor::RemoteCommandResponse& isMasterReply) {
     auto monitor = ReplicaSetMonitorManager::get()->getMonitorForHost(remoteHost);
     if (!monitor) {
         return Status::OK();
@@ -85,19 +85,19 @@ Status ReplicaSetMonitorManagerNetworkConnectionHook::validateHost(
         auto publisher = streamableMonitor->getEventsPublisher();
         if (publisher) {
             try {
-                if (helloReply.status.isOK()) {
+                if (isMasterReply.status.isOK()) {
                     publisher->onServerHandshakeCompleteEvent(
-                        *helloReply.elapsed, remoteHost, helloReply.data);
+                        *isMasterReply.elapsed, remoteHost, isMasterReply.data);
                 } else {
                     publisher->onServerHandshakeFailedEvent(
-                        remoteHost, helloReply.status, helloReply.data);
+                        remoteHost, isMasterReply.status, isMasterReply.data);
                 }
             } catch (const DBException& exception) {
                 LOGV2_ERROR(4712101,
                             "An error occurred publishing a ReplicaSetMonitor handshake event",
                             "error"_attr = exception.toStatus(),
                             "replicaSet"_attr = monitor->getName(),
-                            "handshakeStatus"_attr = helloReply.status);
+                            "handshakeStatus"_attr = isMasterReply.status);
                 return exception.toStatus();
             }
         }
@@ -141,6 +141,10 @@ void ReplicaSetMonitorManager::_setupTaskExecutorAndStatsInLock() {
         return;
     }
 
+    if (!_stats) {
+        _stats = std::make_shared<ReplicaSetMonitorManagerStats>();
+    }
+
     // construct task executor
     auto hookList = std::make_unique<rpc::EgressMetadataHookList>();
     auto networkConnectionHook = std::make_unique<ReplicaSetMonitorManagerNetworkConnectionHook>();
@@ -219,6 +223,7 @@ shared_ptr<ReplicaSetMonitor> ReplicaSetMonitorManager::getMonitorForHost(const
 
 vector<string> ReplicaSetMonitorManager::getAllSetNames() const {
     vector<string> allNames;
+
     stdx::lock_guard<Latch> lk(_mutex);
 
     for (const auto& entry : _monitors) {
@@ -312,31 +317,30 @@ void ReplicaSetMonitorManager::removeAllMonitors() {
 }
 
 void ReplicaSetMonitorManager::report(BSONObjBuilder* builder, bool forFTDC) {
-    std::vector<std::shared_ptr<ReplicaSetMonitor>> monitors;
-    int numMonitorsCreated;
-    // Gather relevant data under the lock. Separate out writing it to BSON.
-    {
-        stdx::lock_guard lk(_mutex);
-        _doGarbageCollectionLocked(lk);
-        for (const auto& [_, weakMonitor] : _monitors) {
-            if (auto monitor = weakMonitor.lock())
-                monitors.push_back(std::move(monitor));
-        }
-        numMonitorsCreated = _numMonitorsCreated;
-    }
-    // Now write out the data.
-    builder->appendNumber("numReplicaSetMonitorsCreated", numMonitorsCreated);
+    // Don't hold _mutex the whole time to avoid ever taking a monitor's mutex while holding the
+    // manager's mutex.  Otherwise we could get a deadlock between the manager's, monitor's, and
+    // ShardRegistry's mutex due to the ReplicaSetMonitor's AsynchronousConfigChangeHook
+    // potentially calling ShardRegistry::updateConfigServerConnectionString.
+    auto setNames = getAllSetNames();
+
+    builder->appendNumber("numReplicaSetMonitorsCreated", _numMonitorsCreated);
 
     {
         BSONObjBuilder setStats(
             builder->subobjStart(forFTDC ? "replicaSetPingTimesMillis" : "replicaSets"));
 
-        for (const auto& monitor : monitors) {
+        for (const auto& setName : setNames) {
+            auto monitor = getMonitor(setName);
+            if (!monitor) {
+                continue;
+            }
             monitor->appendInfo(setStats, forFTDC);
         }
     }
 
-    _stats->report(builder, forFTDC);
+    if (_stats) {
+        _stats->report(builder, forFTDC);
+    }
 }
 
 std::shared_ptr<executor::TaskExecutor> ReplicaSetMonitorManager::getExecutor() {