If the configuration is trivial, I was going to suggest just putting it in a tiny script instead of in powerd. If it's not, I'd recommend creating a new class under powerd/system/ for doing this. Happy to chat more about the design.

Yes, configuration is trivial, a script should be fine. I'm doubting how to best launch it, an own 'service' seems overkill, powerd-pre-start.sh could be an option if that's not considered too hacky.

powerd-pre-start.sh currently just does setup needed by powerd (making directories and changing permissions), so it's probably not the right place for this.

I'd probably recommend just adding a trivial Upstart job in this case. https://chromium.googlesource.com/chromiumos/platform2/+/master/init/README offers some guidance. I think that "task" might be appropriate in this case.

Are there concerns about when this runs in terms of the boot sequence? Like, do we need to worry about it adding more variability to boot times if it sometimes runs earlier or later?

Thanks, let's use an upstart job then.

If we want less variability in boot time we probably want to do the configuration late in the boot process, though it's hard to quantify how much difference it would actually make.

> If we want less variability in boot time we probably want
> to do the configuration late in the boot process, though
> it's hard to quantify how much difference it would actually make.

If there's no hard deadline for running the job, then the
following will make the job run at boot without affecting
boot time:
    start on started system-services

With this formulation, the 'task' keyword is unnecessary, and
actually meaningless.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/overlays/chromiumos-overlay/+/fdb2b5b64a9e91e4d403dca0feea70607e0dbae8

commit fdb2b5b64a9e91e4d403dca0feea70607e0dbae8
Author: Matthias Kaehlcke <mka@chromium.org>
Date: Wed Aug 09 18:48:01 2017

power_manager: Install script to configure cpufreq

BUG= chromium:750290 ,  chromium:214886 
TEST=manual
CQ-DEPEND=CL:596803

Change-Id: Iaf0d7f3b0e55acb12f6832af5b2c45639acf06dd
Reviewed-on: https://chromium-review.googlesource.com/596521
Commit-Ready: Matthias Kaehlcke <mka@chromium.org>
Tested-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Dan Erat <derat@chromium.org>

[modify] https://crrev.com/fdb2b5b64a9e91e4d403dca0feea70607e0dbae8/chromeos-base/power_manager/power_manager-9999.ebuild

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/platform2/+/e06bb4f0e4a8afdedbf42ecb3868f214c76c9bb2

commit e06bb4f0e4a8afdedbf42ecb3868f214c76c9bb2
Author: Matthias Kaehlcke <mka@chromium.org>
Date: Wed Aug 09 18:48:01 2017

power: Add script to configure cpufreq

The script is called at boot and configures cpufreq according to the
information in /etc/cpufreq.conf (if it exists). The current version
only allows extended configuration for the interactive governor. Both
single- and multi-policy configurations are supported.

BUG= chromium:750290 ,  chromium:214886 
TEST=manual
CQ-DEPEND=CL:596521

Change-Id: I29a4e099cfd7e911add6e0a19a15a63e33df3bd4
Reviewed-on: https://chromium-review.googlesource.com/596803
Commit-Ready: Matthias Kaehlcke <mka@chromium.org>
Tested-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Mike Frysinger <vapier@chromium.org>

[add] https://crrev.com/e06bb4f0e4a8afdedbf42ecb3868f214c76c9bb2/power_manager/init/upstart/cpufreq.conf
[add] https://crrev.com/e06bb4f0e4a8afdedbf42ecb3868f214c76c9bb2/power_manager/tools/cpufreq_config

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/overlays/board-overlays/+/d20a0f15dd37886ae39211510581483b2366060d

commit d20a0f15dd37886ae39211510581483b2366060d
Author: Matthias Kaehlcke <mka@chromium.org>
Date: Fri Aug 11 00:12:39 2017

peach-pi: Move cpufreq configuration to cpufreq task

Configure cpufreq with the cpufreq task instead of laptop-mode-tools

BUG= chromium:750290 ,  chromium:214886 
TEST=build and boot peach-pi
  cd /sys/devices/system/cpu/cpufreq/interactive
  cat input_boost
    => 1
  cat hispeed_freq
    => 650000:75 1800000:95
  cat above_hispeed_delay
    => 20000 700000:0 1800000:20000

Change-Id: I73f94194f78379bf205e0e2a7fd93436d5103cdd
Reviewed-on: https://chromium-review.googlesource.com/611010
Commit-Ready: Matthias Kaehlcke <mka@chromium.org>
Tested-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Dan Erat <derat@chromium.org>

[modify] https://crrev.com/d20a0f15dd37886ae39211510581483b2366060d/overlay-variant-peach-pi/chromeos-base/chromeos-bsp-pi/chromeos-bsp-pi-0.0.2.ebuild
[modify] https://crrev.com/d20a0f15dd37886ae39211510581483b2366060d/overlay-variant-peach-pi/chromeos-base/chromeos-bsp-pi/files/cpufreq.conf
[rename] https://crrev.com/d20a0f15dd37886ae39211510581483b2366060d/overlay-variant-peach-pi/chromeos-base/chromeos-bsp-pi/chromeos-bsp-pi-0.0.2-r9.ebuild

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/overlays/board-overlays/+/8e941b7c5e759f72eeba9b4c330cdb568c9c277d

commit 8e941b7c5e759f72eeba9b4c330cdb568c9c277d
Author: Matthias Kaehlcke <mka@chromium.org>
Date: Fri Aug 11 03:24:09 2017

bsp-nyan: Move cpufreq configuration to cpufreq task

Configure cpufreq with the cpufreq task instead of laptop-mode-tools

BUG= chromium:750290 ,  chromium:214886 
TEST=build and boot nyan
  cd /sys/devices/system/cpu/cpufreq/interactive
  cat above_hispeed_delay
    => 19000
  cat hispeed_freq
    => 564000:75 1938000:85
  cat min_sample_time
    => 30000

Change-Id: If67b69a90e51f3c28fd66ea07dd0ebc4f74113cd
Reviewed-on: https://chromium-review.googlesource.com/610503
Commit-Ready: Matthias Kaehlcke <mka@chromium.org>
Tested-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Dan Erat <derat@chromium.org>

[modify] https://crrev.com/8e941b7c5e759f72eeba9b4c330cdb568c9c277d/overlay-nyan/chromeos-base/chromeos-bsp-nyan/files/cpufreq.conf
[rename] https://crrev.com/8e941b7c5e759f72eeba9b4c330cdb568c9c277d/overlay-nyan/chromeos-base/chromeos-bsp-nyan/chromeos-bsp-nyan-0.0.1-r17.ebuild
[modify] https://crrev.com/8e941b7c5e759f72eeba9b4c330cdb568c9c277d/overlay-nyan/chromeos-base/chromeos-bsp-nyan/chromeos-bsp-nyan-0.0.1.ebuild

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/overlays/board-overlays/+/e2f8f9272ab5acc0b41a6625742314d178811ced

commit e2f8f9272ab5acc0b41a6625742314d178811ced
Author: Matthias Kaehlcke <mka@chromium.org>
Date: Fri Aug 11 03:24:12 2017

baseboard-gru: Move cpufreq configuration to cpufreq task

Configure cpufreq with the cpufreq task instead of laptop-mode-tools
(LMT).

BUG= chromium:750290 ,  chromium:214886 
TEST=build and boot kevin
  cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
    sched
    sched
    ...

Change-Id: I2c383a59e1971ee965851f13110fda553d03e082
Reviewed-on: https://chromium-review.googlesource.com/611201
Commit-Ready: Matthias Kaehlcke <mka@chromium.org>
Tested-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Dan Erat <derat@chromium.org>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>

[rename] https://crrev.com/e2f8f9272ab5acc0b41a6625742314d178811ced/baseboard-gru/chromeos-base/chromeos-bsp-baseboard-gru/chromeos-bsp-baseboard-gru-0.0.3-r9.ebuild
[modify] https://crrev.com/e2f8f9272ab5acc0b41a6625742314d178811ced/baseboard-gru/chromeos-base/chromeos-bsp-baseboard-gru/chromeos-bsp-baseboard-gru-0.0.3.ebuild
[modify] https://crrev.com/e2f8f9272ab5acc0b41a6625742314d178811ced/baseboard-gru/chromeos-base/chromeos-bsp-baseboard-gru/files/cpufreq.conf

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/overlays/board-overlays/+/3ca4a16b3b330ba47be4f6cf0fcd08d4ccd50f49

commit 3ca4a16b3b330ba47be4f6cf0fcd08d4ccd50f49
Author: Matthias Kaehlcke <mka@chromium.org>
Date: Sat Aug 12 01:07:06 2017

bsp-baseboard-oak: Move cpufreq configuration to cpufreq task

Configure cpufreq with the cpufreq task instead of laptop-mode-tools
(LMT).

BUG= chromium:750290 ,  chromium:214886 
TEST=build and boot oak
  cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
    sched
    sched
    ...

Change-Id:  I12fbea9b231b1a3fd2967429936213a34df19d1a
Reviewed-on: https://chromium-review.googlesource.com/611003
Commit-Ready: Matthias Kaehlcke <mka@chromium.org>
Tested-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Dan Erat <derat@chromium.org>
Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>

[rename] https://crrev.com/3ca4a16b3b330ba47be4f6cf0fcd08d4ccd50f49/baseboard-oak/chromeos-base/chromeos-bsp-baseboard-oak/chromeos-bsp-baseboard-oak-0.0.1-r6.ebuild
[modify] https://crrev.com/3ca4a16b3b330ba47be4f6cf0fcd08d4ccd50f49/baseboard-oak/chromeos-base/chromeos-bsp-baseboard-oak/files/cpufreq.conf
[modify] https://crrev.com/3ca4a16b3b330ba47be4f6cf0fcd08d4ccd50f49/baseboard-oak/chromeos-base/chromeos-bsp-baseboard-oak/chromeos-bsp-baseboard-oak-0.0.1.ebuild

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/overlays/board-overlays/+/8bd88d668ef1fc62ab71a7c6e24df8aad620440f

commit 8bd88d668ef1fc62ab71a7c6e24df8aad620440f
Author: Matthias Kaehlcke <mka@chromium.org>
Date: Sat Aug 12 01:07:04 2017

peach-pit: Move cpufreq configuration to cpufreq task

Configure cpufreq with the cpufreq task instead of laptop-mode-tools

BUG= chromium:750290 ,  chromium:214886 
TEST=build and boot peach-pit
  cd /sys/devices/system/cpu/cpufreq/interactive
  cat input_boost
    => 1
  cat hispeed_freq
    => 650000:75 1600000:95
  cat above_hispeed_delay
    => 20000 700000:0 1600000:20000

Change-Id: Ice7b812f68f6e62cd260f92d95b817ff44d96286
Reviewed-on: https://chromium-review.googlesource.com/611133
Commit-Ready: Matthias Kaehlcke <mka@chromium.org>
Tested-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Dan Erat <derat@chromium.org>

[rename] https://crrev.com/8bd88d668ef1fc62ab71a7c6e24df8aad620440f/overlay-variant-peach-pit/chromeos-base/chromeos-bsp-pit/chromeos-bsp-pit-0.0.2-r8.ebuild
[modify] https://crrev.com/8bd88d668ef1fc62ab71a7c6e24df8aad620440f/overlay-variant-peach-pit/chromeos-base/chromeos-bsp-pit/files/cpufreq.conf
[modify] https://crrev.com/8bd88d668ef1fc62ab71a7c6e24df8aad620440f/overlay-variant-peach-pit/chromeos-base/chromeos-bsp-pit/chromeos-bsp-pit-0.0.2.ebuild

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/overlays/board-overlays/+/b33fc77034b6b5edfa063170e142fcdbcc1644a7

commit b33fc77034b6b5edfa063170e142fcdbcc1644a7
Author: Matthias Kaehlcke <mka@chromium.org>
Date: Sat Aug 12 01:07:04 2017

link: Move cpufreq configuration to cpufreq task

Configure cpufreq with the cpufreq task instead of laptop-mode-tools

BUG= chromium:750290 ,  chromium:214886 
TEST=build and boot link
  cd /sys/devices/system/cpu/cpufreq/interactive
  cat input_boost
    => 1
  cat timer_rate
    => 10000
  cat min_sample_time
    => 40000
  cat hispeed_freq
    => 1800000:95

Change-Id: Ic71afa8fa06154669c7c5724d93e17afc0ae9ef2
Reviewed-on: https://chromium-review.googlesource.com/612447
Commit-Ready: Matthias Kaehlcke <mka@chromium.org>
Tested-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Dan Erat <derat@chromium.org>

[modify] https://crrev.com/b33fc77034b6b5edfa063170e142fcdbcc1644a7/overlay-link/chromeos-base/chromeos-bsp-link/files/cpufreq.conf
[rename] https://crrev.com/b33fc77034b6b5edfa063170e142fcdbcc1644a7/overlay-link/chromeos-base/chromeos-bsp-link/chromeos-bsp-link-0.0.2-r31.ebuild
[modify] https://crrev.com/b33fc77034b6b5edfa063170e142fcdbcc1644a7/overlay-link/chromeos-base/chromeos-bsp-link/chromeos-bsp-link-0.0.2.ebuild

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/overlays/board-overlays/+/f37f9b379e988968e9441f8b315100f4e6e63bca

commit f37f9b379e988968e9441f8b315100f4e6e63bca
Author: Matthias Kaehlcke <mka@chromium.org>
Date: Fri Aug 18 01:42:28 2017

bsp-daisy: Move cpufreq configuration to cpufreq task

Configure cpufreq with the cpufreq task instead of laptop-mode-tools
(LMT).

The ignore_nice_load attribute set in the LMT configuration is not
supported by the v3.8 kernel running on daisy.

BUG= chromium:750290 ,  chromium:214886 
TEST=build and boot skate
  cat /sys/devices/system/cpu/cpufreq/interactive/input_boost
    => 1

Change-Id: Ib835bcc219007c92a5237ed8031b12fdd0ff5708
Reviewed-on: https://chromium-review.googlesource.com/610470
Commit-Ready: Matthias Kaehlcke <mka@chromium.org>
Tested-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Dan Erat <derat@chromium.org>

[rename] https://crrev.com/f37f9b379e988968e9441f8b315100f4e6e63bca/overlay-daisy/chromeos-base/chromeos-bsp-daisy/chromeos-bsp-daisy-0.0.2-r9.ebuild
[modify] https://crrev.com/f37f9b379e988968e9441f8b315100f4e6e63bca/overlay-daisy/chromeos-base/chromeos-bsp-daisy/files/cpufreq.conf
[modify] https://crrev.com/f37f9b379e988968e9441f8b315100f4e6e63bca/overlay-daisy/chromeos-base/chromeos-bsp-daisy/chromeos-bsp-daisy-0.0.2.ebuild

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/overlays/board-overlays/+/b80a298677ffc7805c74c0d228d2c71827a51de1

commit b80a298677ffc7805c74c0d228d2c71827a51de1
Author: Matthias Kaehlcke <mka@chromium.org>
Date: Fri Feb 02 11:40:36 2018

chromeos-bsp-veyron: Move cpufreq configuration to cpufreq task

Configure cpufreq with the cpufreq task instead of laptop-mode-tools

BUG= chromium:750290 ,  chromium:214886 
TEST=build and boot veyron_mighty
  cd /sys/devices/system/cpu/cpufreq/interactive
  cat hispeed_freq
    => 1200000
  cat go_hispeed_load
    => 95

Change-Id: I2714915338094f8b31c09aa2f326bea92fb43967
Reviewed-on: https://chromium-review.googlesource.com/898583
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Tested-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Dan Erat <derat@chromium.org>

[rename] https://crrev.com/b80a298677ffc7805c74c0d228d2c71827a51de1/overlay-veyron/chromeos-base/chromeos-bsp-veyron/chromeos-bsp-veyron-0.0.1-r28.ebuild
[modify] https://crrev.com/b80a298677ffc7805c74c0d228d2c71827a51de1/overlay-veyron/chromeos-base/chromeos-bsp-veyron/files/cpufreq.conf
[modify] https://crrev.com/b80a298677ffc7805c74c0d228d2c71827a51de1/overlay-veyron/chromeos-base/chromeos-bsp-veyron/chromeos-bsp-veyron-0.0.1.ebuild