cgroup already uses floating point for percent[ile] numbers and there are several controllers which want to take them as input. Add a generic parse helper to handle inputs. Update the interface convention documentation about the use of percentage numbers. While at it, also clarify the default time unit. Bug: 120440300 Signed-off-by: Tejun Heo <tj@kernel.org> (cherry picked from commit a5e112e6424adb77d953eac20e6936b952fd6b32) Signed-off-by: Qais Yousef <qais.yousef@arm.com> Change-Id: Ic1fcf21d7955eb8edd2e8e91517bca6aef41694f Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Naveen <133593113+elohim-etz@users.noreply.github.com>