A processing block is equipped with a storage to facilitate storage and maintenance of a thread switching structure to provide multi-threading support in a light-weight manner. In various embodiments, the structure includes a current thread identifier, and a thread array of thread entries describing the threads to be executed interleavingly. Further, in various embodiments, the processing block includes an execution sub-block and a thread management sub-block equipped to support at least a create thread, a thread execution termination, and a thread execution switching instruction.