Linux Kernel compiles all the sources for a single a syscall

Hi, I have compiled 3.4 kernel. Following the tutorial <http://blog.techveda.org/adding-system-calls-linux-kernel-3-5-x/>, I have updated syscall_64.tbl and triggered a 'make'. Now it has started elaborate compilation process, e.g. /fs/*.o sources. Shouldn't make only compile the changed files?