Detecting a state change in a lock structure to validate a potential deadlock

摘要

A mechanism for deadlock validation is provided. A potential deadlock is validated by detecting whether a state change has occurred in a member of a set of lock structures that correspond to entities and resources involved in a potential deadlock. The state change detected should have occurred after the state of the lock structures is captured during, for example, the generation of a wait-for graph. For purposes of illustration, potential deadlocks are identified by generating a wait-for graph and detecting cycles in the wait-for graph. While generating wait-for graphs, lock structures are accessed to determine whether a vertex in the wait-for graph should be generated, and the place of the vertex in the wait-for graph. After accessing a particular lock structure for this purpose, the lock structure's state is captured. If the state of the lock structure changes after the state is captured, then any cycle that includes the lock structure may not be valid, and a potential deadlock identified by the cycle is deemed a false deadlock.