Built a simple CPU benchmarking app for android / ARM Low lever programming skills needed

We need a small app that will create CPU load generating threads capable to only occupy certain percentage (x%) of the available (from 100%) CPU power, e.g. adding a 10%, 15% or 50% of (extra to current) CPU Load The app will need to target Android and will need to be written as 'close to the hardware' as possible (low-level C/ARM assembly and Android O/S programming skills will be needed)