[systemd-devel] Fwd: best way to handle service restarts after hibernate/suspend?

[Mathijs Kwik]

Hi all,

I have a few things that need to get run after waking up my laptop
(things like hdparm to set device power options/spindown time).
I created oneshot, remainafterexit services for those and made them
wanted by multi-user.target.This works fine for the first boot.

As I consider these services "dead" after a suspend/hibernate, I added
Conflicts=sleep.target, so now systemd is aware that these services
are no longer active after a wakeup.

Now I would like to somehow have these services restart on wakeup.
I can add these services to some new target(wakeup.target), but I
don't know how to proceed from there. I thought of making
wakeup.target WantedBy suspend.target, After suspend.target, but since
suspend.target pulls in sleep.target (which conflicts with these
services) that will fail. More so, after wakeup.target is started the
first time, it will never go down itself, so the second wakeup won't
do anything. The same is true for multi-user.target, once that is
reached/activated on first boot, it never deactivates until shutdown.

How should a situation like this be handled?
Ideally, I don't want to use:
- /usr/lib/systemd/system-sleep  (considered hacky)
- a service/script that runs "systemctl start ..."  (secret
dependency, hidden from systemd)

Thanks,
Mathijs