Support being executed at build time in a container

[cgwalters]

I work on Fedora bootc and RHEL Image Mode. We got a bug report that https://src.fedoraproject.org/rpms/ec2-hibinit-agent fails to install at container build time.

This is because its %post ends up invoking tuned:
https://src.fedoraproject.org/rpms/ec2-hibinit-agent/blob/rawhide/f/ec2-hibinit-agent.spec#_126

I think it'd make sense to change tuned to ensure it can work in a "oneshot" mode, without being a daemon. This would entail it basically just writing the files and being done. Note that kernel arguments would need to use bootc kargs in this case.

[yarda]

As a workaround you could either stop TuneD deamon (if runing), enable the no daemon (one shot) mode in /etc/tuned/tuned-main.conf, set daemon = 0, run tuned-adm profile virtual-guest, disable the one shot mode in the etc/tuned/tuned-main.conf by returning daemon = 1,

or alternatively you could emulate the tuned-adm behavior and write the active profile setting yourself without starting the daemon (but it's unsupported):

# echo  virtual-guest > /etc/tuned/active_profile
# echo manual > /etc/tuned/profile_mode