EMULATION OF STRONGLY ORDERED MEMORY MODELS

摘要

In a computer system comprising a memory (50), one or more processors (54, 56, 58), and a controller unit (60) coupled with the or each processor and the memory, virtual page class key protection is used to ensure that multiple threads (52) of a process may not concurrently access pages (64) of memory. A virtual page class is assigned to each thread, and no thread is ever permitted to access another thread's class, so all pages (64) of memory (50) are effectively partitioned into classes according to which thread is using them. When multiple threads need access to a page of memory, it is placed in a special shared class which all threads may access. All pages in the shared class are also marked with strong access ordering mode to ensure strong memory ordering semantics apply when needed. Pages not in the shared class do not need strong access ordering enabled as they are guaranteed to be accessible by only a single thread.