Automatic Fine-Grain Locking using Shape Properties
We present a technique for automatically adding fine-grain locking to an abstract data type that is implemented using a dynamic forest -i.e., the data structures may be mutated, even to the point of violating forestness temporarily during the execution of a method of the ADT. Our automatic technique is based on Domination Locking, a novel locking protocol. Domination locking is designed specifically for software concurrency control, and in particular is designed for object-oriented software with destructive pointer updates. Domination locking is a strict generalization of existing locking protocols for dynamically changing graphs. We show our technique can successfully add fine-grain locking to libraries where manually performing locking is extremely challenging. We show that automatic fine-grain locking is more efficient than coarse-grain locking, and obtains similar performance to hand-crafted fine-grain locking.