1 files changed, 112 insertions, 0 deletions
diff --git a/src/mongo/util/latch_analyzer.cpp b/src/mongo/util/latch_analyzer.cpp
new file mode 100644
index 00000000000..5a868fedb05
--- /dev/null
+++ b/src/mongo/util/latch_analyzer.cpp
@@ -0,0 +1,112 @@
+/**
+ *    Copyright (C) 2018-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.
+ */
+
+#include "mongo/platform/basic.h"
+
+#include "mongo/db/client.h"
+#include "mongo/platform/mutex.h"
+
+namespace mongo {
+
+using Set = HierarchicalAcquisitionSet;
+
+namespace {
+
+const auto getLatchSetState = Client::declareDecoration<Mutex::LatchSetState>();
+
+/**
+ * LockListener sub-class to implement updating set in LatchSetState
+ */
+class MutexLockListener : public Mutex::LockListener {
+
+public:
+    void onContendedLock(const Mutex::Identity&) {
+        // Do nothing
+    }
+
+    void onQuickLock(const Mutex::Identity& id) {
+        onAcquire(id);
+    }
+
+    void onSlowLock(const Mutex::Identity& id) {
+        onAcquire(id);
+    }
+
+    void onUnlock(const Mutex::Identity& id) {
+        onRelease(id);
+    }
+
+private:
+    void onAcquire(const Mutex::Identity& id) {
+        if (!id.level) {
+            return;
+        }
+        if (auto client = Client::getCurrent()) {
+            auto& handle = getLatchSetState(client);
+            auto result = handle.levelsHeld.add(id.level.get());
+            if (result != Set::AddResult::kValidWasAbsent) {
+                // TODO: SERVER-44570 Create a non process-fatal variant of invariant()
+                fassert(31360,
+                        Status(ErrorCodes::HierarchicalAcquisitionLevelViolation,
+                               str::stream()
+                                   << "Theoretical deadlock alert - " << toString(result)
+                                   << " latch acquisition at " << id.sourceLocation->toString()
+                                   << " on " << id.name));
+            }
+        }
+    }
+
+    void onRelease(const Mutex::Identity& id) {
+        if (!id.level) {
+            return;
+        }
+        if (auto client = Client::getCurrent()) {
+            auto& handle = getLatchSetState(client);
+            auto result = handle.levelsHeld.remove(id.level.get());
+            if (result != Set::RemoveResult::kValidWasPresent) {
+                // TODO: SERVER-44570 Create a non process-fatal variant of invariant()
+                fassert(31361,
+                        Status(ErrorCodes::HierarchicalAcquisitionLevelViolation,
+                               str::stream()
+                                   << "Theoretical deadlock alert - " << toString(result)
+                                   << " latch release at " << id.sourceLocation->toString()
+                                   << " on " << id.name));
+            }
+        }
+    }
+};
+
+MONGO_INITIALIZER(CreateMutexLockListener)(InitializerContext* context) {
+    static auto& listener = *new MutexLockListener;
+    Mutex::addLockListener(&listener);
+    return Status::OK();
+}
+
+}  // namespace
+}  // namespace mongo