A possible method for preventing deadlocks is to have a

A possible method for preventing deadlocks is to have a single, higher­ order resource that must be requested before any other resource. For example, if multiple threads attempt to access the synchronization objects A··· E, deadlock is possible. (Such synchronization objects may include mutexes, semaphores, condition variables, and the like.) We can prevent the deadlock by adding a sixth object F. Whenever a thread wants to acquire the synchronization lock for any object A··· E, it must first acquire the lock for object F. This solution is known as containment: the locks for objects A··· E are contained within the lock for object F. Compare this scheme with the circular-wait scheme of Section 7.4.4



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