fps_meter: measuring fps with ftrace

Sample output:
[111111111111111111111111111111111111111111111111111111111111] FPS: 60
[11111111111111 11111111111111111111 11111111 111111111111111] FPS: 57
[111111111111111111111111111111111    11111111111111111111111] FPS: 56

BUG=chromium:805780
TEST=manual test

Change-Id: Id174a1027aca4e7d3365338331a64f16cf886f04
Reviewed-on: https://chromium-review.googlesource.com/880532
Commit-Ready: Vovo Yang <vovoy@chromium.org>
Tested-by: Vovo Yang <vovoy@chromium.org>
Reviewed-by: Cheng-Yu Lee <cylee@google.com>
1 file changed
tree: 60e569132502ed0cf19b5b160c008462817d9298
  1. README
  2. fps_meter/
  3. power-model/