The kernel does calculate jiffies per second at start-up, but I don't think that is exported to userspace. Another issue is that the userspace latency is 10ms -- ie, you cannot get any finer granularity than that with accuracy (I think there are some options in the 3.0 kernel to do with this). So maybe you do need a kernel module; the hardest part of that is just learning the methodology. If you google for the "hello world" kernel module, all you need on top of that is a char driver to create a /dev file for the interface. The 2nd or 3rd edition of "linux device drivers" is free online and explains how to do this.
Thanks, (miliseconds is accurate enough) now I've gotta find the functions that convert from uptime -> jiffies, and jiffies -> msec.