Lock-Free Techniques for Concurrent Access to Shared Objects

Concurrent access to shared data in preemptive multi-tasks environment and in multi-processors architecture have been subject of many works. Proposed solutions are commonly based on semaphores which have several drawbacks. For many cases, lock-free techniques constitute an alternate solution and avoid the disadvantages of semaphore based techniques. We present the principle of these lock-free techniques with the simple example of a LIFO stack. Then, based on Michael-Scott previous work, we propose a new algorithm to implements lock-free FIFO stacks with a simple constraint on the data structure.