Using AspectC to Improve the Modularity of Path-Specific Customization in Operating System Code
Yvonne Coady, Gregor Kiczales, Mike Feeley, and Greg Smolyn

In Proceedings of the Joint European Software Engineering Conference (ESEC) and 9th ACM SIGSOFT Internation Symposium on the Foundations of Software Engineering (FSE-9)

Abstract

Layered architecture in operating system code is often compromised by execution path-specific customizations such as prefetching, page replacement and scheduling strategies. Path-specific customizations are difficult to modularize in a layered architecture because they involve dynamic context passing and layer violations. Effectively they are vertically integrated slices through the layers.

An initial experiment using an aspect-oriented programming language to refactor prefetching in the FreeBSD operating system kernel shows significant benefits, including easy (un)pluggability of prefetching modes, independent development of prefetching modes, and overall improved comprehensibility.