A more pragmatic implementation of the lock-free, ordered, linked list

The lock-free, ordered, singly linked list as proposed in [5, 8] is a textbook example of a concurrent data structure [6, 10]. The data structure supports lock-free insertion and deletion, and wait-free contains operations on items identified by a unique key. The lock-free implementation is actually quite subtle. The ordering condition and a relaxed invariant makes it possible to do with a single-word Compare-And-Swap operation (CAS), and all operations can be shown to be linearizable even though linearization does not always happen at fixed points in the code. The lock-free data structure has many direct and indirect applications, notably in the implementation of concurrent skiplists and hash tables [8, 9, 11, 12].