??Hi Peng,

Well, an atomic counter would suffice, and if you need to secure the counter, you could wrap it around with a server. You either need a hardware upcounter, or else a periodic event-timer that you can use to emulate a hardware upcounter; from there, you just use your upcounter for your jiffies. Libplatsupport has userspace timer drivers for most platforms we support: https://github.com/seL4/util_libs/tree/master/libplatsupport?

Kofi Doku Atuah Kernel engineer DATA61 | CSIRO E kofidoku.atuah@data61.csiro.au www.data61.csiro.au

CSIRO's Digital Productivity business unit and NICTA have joined forces to create digital powerhouse Data61 ________________________________ From: Devel devel-bounces@sel4.systems on behalf of PX seawolf.peng@gmail.com Sent: 29 November 2016 08:27 To: devel@sel4.systems Subject: [seL4] how to get timing information on seL4 user space

Hi, all I want to get number of ticks, similar to jiffies in Linux, in the ARM seL4 user space. How can I do it? Are there existing libraries I can use? If not, what's the best way to implement it?

thanks Peng