SERVER-44522 serverStatus metrics for awaitable isMaster

1 files changed, 98 insertions, 0 deletions

diff --git a/src/mongo/transport/ismaster_metrics.cpp b/src/mongo/transport/ismaster_metrics.cpp
new file mode 100644
index 00000000000..3179f28d2fb
--- /dev/null
+++ b/src/mongo/transport/ismaster_metrics.cpp
@@ -0,0 +1,98 @@
+/**
+ *    Copyright (C) 2020-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the Server Side Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+#define MONGO_LOG_DEFAULT_COMPONENT ::mongo::logger::LogComponent::kNetwork
+#include "mongo/transport/ismaster_metrics.h"
+#include "mongo/util/log.h"
+
+namespace mongo {
+namespace {
+const auto IsMasterMetricsDecoration = ServiceContext::declareDecoration<IsMasterMetrics>();
+const auto InExhaustIsMasterDecoration = transport::Session::declareDecoration<InExhaustIsMaster>();
+}  // namespace
+
+IsMasterMetrics* IsMasterMetrics::get(ServiceContext* service) {
+    return &IsMasterMetricsDecoration(service);
+}
+
+IsMasterMetrics* IsMasterMetrics::get(OperationContext* opCtx) {
+    return get(opCtx->getServiceContext());
+}
+
+size_t IsMasterMetrics::getNumExhaustIsMaster() const {
+    return _exhaustIsMasterConnections.load();
+}
+
+void IsMasterMetrics::incrementNumExhaustIsMaster() {
+    _exhaustIsMasterConnections.fetchAndAdd(1);
+}
+
+void IsMasterMetrics::decrementNumExhaustIsMaster() {
+    _exhaustIsMasterConnections.fetchAndSubtract(1);
+}
+
+size_t IsMasterMetrics::getNumAwaitingTopologyChanges() const {
+    return _connectionsAwaitingTopologyChanges.load();
+}
+
+void IsMasterMetrics::incrementNumAwaitingTopologyChanges() {
+    _connectionsAwaitingTopologyChanges.fetchAndAdd(1);
+}
+
+void IsMasterMetrics::decrementNumAwaitingTopologyChanges() {
+    _connectionsAwaitingTopologyChanges.fetchAndSubtract(1);
+}
+
+void IsMasterMetrics::resetNumAwaitingTopologyChanges() {
+    _connectionsAwaitingTopologyChanges.store(0);
+}
+
+InExhaustIsMaster* InExhaustIsMaster::get(transport::Session* session) {
+    return &InExhaustIsMasterDecoration(session);
+}
+
+InExhaustIsMaster::~InExhaustIsMaster() {
+    if (_inExhaustIsMaster) {
+        IsMasterMetrics::get(getGlobalServiceContext())->decrementNumExhaustIsMaster();
+    }
+}
+
+bool InExhaustIsMaster::getInExhaustIsMaster() const {
+    return _inExhaustIsMaster;
+}
+
+void InExhaustIsMaster::setInExhaustIsMaster(bool inExhaustIsMaster) {
+    if (!_inExhaustIsMaster && inExhaustIsMaster) {
+        IsMasterMetrics::get(getGlobalServiceContext())->incrementNumExhaustIsMaster();
+    } else if (_inExhaustIsMaster && !inExhaustIsMaster) {
+        IsMasterMetrics::get(getGlobalServiceContext())->decrementNumExhaustIsMaster();
+    }
+    _inExhaustIsMaster = inExhaustIsMaster;
+}
+
+}  // namespace mongo
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