I'm revisiting some old topics as part of research that requires me to extract information out of the kernel but whose instrumentation is not really worth merging to mainline. At one point, I extracted this information using a kernel module relaying additional information stored in struct page to userspace. It's not smart or clever but the options were limited at the time. This time around, I intend to give SystemTap a go as it should be able to do this type of job.
When I last used SystemTap, it was a total and utter pain to install which was also one of the main critisms levelled at it during one of the kernel summits. I had an installation script at the time to automate installation but it was a kludge of workarounds and patches. Since then, things have improved considerably because the reworked
installation script for the current release is downright trivial and 180 lines shorter than the previous version. A 2 minute glance through the example scripts show considerable improvement in terms of usability and readability as well.
I haven't figured out if systemtap is usable for my needs or not yet but things certainly appear to be going in the right direction on that front.
