And to save the step:

config CPU_BOOST
	tristate "Input event based short term CPU freq booster"
	depends on INPUT
	help
	  This driver monitors events from input devices, such as
	  touchscreen, trackpad, keyboard, etc., and boosts frequency
	  of all CPUs in the system in response to user interacting with
	  the device.

	  If in doubt, say N.

4.4, for reference:

$ git grep CONFIG_CPU_BOOST -- chromeos
chromeos/config/arm64/chromiumos-arm64.flavour.config:# CONFIG_CPU_BOOST is not set
chromeos/config/arm64/chromiumos-mediatek.flavour.config:CONFIG_CPU_BOOST=y
chromeos/config/arm64/chromiumos-rockchip64.flavour.config:CONFIG_CPU_BOOST=y
chromeos/config/armel/common.config:# CONFIG_CPU_BOOST is not set
chromeos/config/i386/common.config:# CONFIG_CPU_BOOST is not set
chromeos/config/x86_64/common.config:# CONFIG_CPU_BOOST is not set

I'm somewhat ignorant but on x86 -- at least Intel systems -- isn't there a black box called DPTF that controls frequency based on some load mesuarement?  would CPU_BOOST be able to do anything there?

@3: If you're ignorant then I'm even more so.  ...but that would be a good argument for this to be off on x86.  Seems like we should turn this on for all arm / arm64 though?

yeah probably makes sense to turn it on for all arm -- especially if we're not using the interactive governor in favor of some EAS type thing

I'm just going to do the simple thing and turn it on for "chromiumos-arm64.flavour.config".  Justification:

* arm32: if we moved one of these up (likely veyron) we'd use the interactive governor.

* arm64: we should just standardize on using sched governor.

* x86: it's a magic black box so doesn't need CPU_BOOST.

Sorry for delay ...  At least for most recent intel projects we've used the intel pstate driver which in turn has its own powersave & performance governors so I don't believe CPU_BOOST would have any affect (nor any harm if it were enabled I suspect)

Agreed rolling it on for just arm64 sgtm.

4.4: https://chromium-review.googlesource.com/#/c/chromiumos/third_party/kernel/+/907108
4.14: https://chromium-review.googlesource.com/#/c/chromiumos/third_party/kernel/+/906920

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/third_party/kernel/+/369228868afb7b43d90a1df011b85a96f5db6893

commit 369228868afb7b43d90a1df011b85a96f5db6893
Author: Douglas Anderson <dianders@chromium.org>
Date: Wed Feb 07 23:04:15 2018

CHROMIUM: config: All arm64 get CPU_BOOST

There's no reason for chromiumos-arm64.flavour.config to have this
off.  Set it and have this bubble back up to the arm64 common.config.

This is equivalent to:
  echo 'CONFIG_CPU_BOOST=y' >> \
    chromeos/config/arm64/chromiumos-arm64.flavour.config
  ./chromeos/scripts/kernelconfig oldconfig

...atop and already normlized config.

BUG= chromium:806932 
TEST=None

Change-Id: I6cd6752172c92127afdbac439033804132c7408e
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/906920
Reviewed-by: Guenter Roeck <groeck@chromium.org>

[modify] https://crrev.com/369228868afb7b43d90a1df011b85a96f5db6893/chromeos/config/arm64/chromiumos-rockchip64.flavour.config
[modify] https://crrev.com/369228868afb7b43d90a1df011b85a96f5db6893/chromeos/config/arm64/chromiumos-arm64.flavour.config
[modify] https://crrev.com/369228868afb7b43d90a1df011b85a96f5db6893/chromeos/config/arm64/chromiumos-mediatek.flavour.config
[modify] https://crrev.com/369228868afb7b43d90a1df011b85a96f5db6893/chromeos/config/arm64/chromiumos-qualcomm.flavour.config
[modify] https://crrev.com/369228868afb7b43d90a1df011b85a96f5db6893/chromeos/config/arm64/common.config

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/third_party/kernel/+/69e7be208cb424fbcd19e805c13e860f33262632

commit 69e7be208cb424fbcd19e805c13e860f33262632
Author: Douglas Anderson <dianders@chromium.org>
Date: Thu Feb 08 09:24:29 2018

CHROMIUM: config: All arm64 get CPU_BOOST

There's no reason for chromiumos-arm64.flavour.config to have this
off.  Set it and have this bubble back up to the arm64 common.config.

This is equivalent to:
  echo 'CONFIG_CPU_BOOST=y' >> \
    chromeos/config/arm64/chromiumos-arm64.flavour.config
  ./chromeos/scripts/kernelconfig oldconfig

...atop and already normlized config.

BUG= chromium:806932 
TEST=None

Change-Id: I6cd6752172c92127afdbac439033804132c7408e
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/907108
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Reviewed-by: Guenter Roeck <groeck@chromium.org>

[modify] https://crrev.com/69e7be208cb424fbcd19e805c13e860f33262632/chromeos/config/arm64/chromiumos-rockchip64.flavour.config
[modify] https://crrev.com/69e7be208cb424fbcd19e805c13e860f33262632/chromeos/config/arm64/chromiumos-arm64.flavour.config
[modify] https://crrev.com/69e7be208cb424fbcd19e805c13e860f33262632/chromeos/config/arm64/chromiumos-mediatek.flavour.config
[modify] https://crrev.com/69e7be208cb424fbcd19e805c13e860f33262632/chromeos/config/arm64/common.config