A technique for controlling access to resources that may be accessed by one or more entities in a system. According to the technique, an entity accesses a shared resource by issuing a request containing an identifier that identifies the resource and an operation that specifies an operation to be performed on the resource. The operation is compared with one or more outstanding operations associated with the shared resource to determine if the operation conflicts with one or more of the outstanding operations. If a conflict is detected, a guard value is applied to determine if a race condition could occur. If a race condition is detected, the operation is blocked; otherwise, the operation is allowed.