SERVER-54024 Use lock-free collection helpers in some auth read lookups and RolesLocks.

1 files changed, 19 insertions, 0 deletions

diff --git a/src/mongo/db/db_raii.h b/src/mongo/db/db_raii.h
index 0fa2d3526ed..f9ad58e9a4b 100644
--- a/src/mongo/db/db_raii.h
+++ b/src/mongo/db/db_raii.h
@@ -399,6 +399,25 @@ private:
 };
 
 /**
+ * Acquires the global MODE_IS lock and establishes a consistent CollectionCatalog and storage
+ * snapshot.
+ */
+class AutoReadLockFree {
+public:
+    AutoReadLockFree(OperationContext* opCtx, Date_t deadline = Date_t::max());
+
+private:
+    // The CollectionCatalogStasher must outlive the LockFreeReadsBlock below. ~LockFreeReadsBlock
+    // clears a flag that the ~CollectionCatalogStasher checks.
+    CollectionCatalogStasher _catalogStash;
+
+    // Sets a flag on the opCtx to inform subsequent code that the operation is running lock-free.
+    LockFreeReadsBlock _lockFreeReadsBlock;
+
+    Lock::GlobalLock _globalLock;
+};
+
+/**
  * Establishes a consistent CollectionCatalog with a storage snapshot. Also verifies Database
  * sharding state for the provided Db. Takes MODE_IS global lock.
  *