nixpkgs/nixos/modules/config/power-management.nix
Guillaume Girol 5d07c39b14 nixos/power-management: fix deadlock with post-resume.{target,service}
Fixes a deadlock where post-resume.target has After=post-resume.service
and post-resume.service runs systemctl try-restart post-resume.target
the systemctl call cannot complete if post-resume.target was already
queued at that time.
2022-11-03 12:00:00 +00:00

107 lines
2.6 KiB
Nix

{ config, lib, ... }:
with lib;
let
cfg = config.powerManagement;
in
{
###### interface
options = {
powerManagement = {
enable = mkOption {
type = types.bool;
default = true;
description =
lib.mdDoc ''
Whether to enable power management. This includes support
for suspend-to-RAM and powersave features on laptops.
'';
};
resumeCommands = mkOption {
type = types.lines;
default = "";
description = lib.mdDoc "Commands executed after the system resumes from suspend-to-RAM.";
};
powerUpCommands = mkOption {
type = types.lines;
default = "";
example = literalExpression ''
"''${pkgs.hdparm}/sbin/hdparm -B 255 /dev/sda"
'';
description =
lib.mdDoc ''
Commands executed when the machine powers up. That is,
they're executed both when the system first boots and when
it resumes from suspend or hibernation.
'';
};
powerDownCommands = mkOption {
type = types.lines;
default = "";
example = literalExpression ''
"''${pkgs.hdparm}/sbin/hdparm -B 255 /dev/sda"
'';
description =
lib.mdDoc ''
Commands executed when the machine powers down. That is,
they're executed both when the system shuts down and when
it goes to suspend or hibernation.
'';
};
};
};
###### implementation
config = mkIf cfg.enable {
systemd.targets.post-resume = {
description = "Post-Resume Actions";
requires = [ "post-resume.service" ];
after = [ "post-resume.service" ];
wantedBy = [ "sleep.target" ];
unitConfig.StopWhenUnneeded = true;
};
# Service executed before suspending/hibernating.
systemd.services.pre-sleep =
{ description = "Pre-Sleep Actions";
wantedBy = [ "sleep.target" ];
before = [ "sleep.target" ];
script =
''
${cfg.powerDownCommands}
'';
serviceConfig.Type = "oneshot";
};
systemd.services.post-resume =
{ description = "Post-Resume Actions";
after = [ "suspend.target" "hibernate.target" "hybrid-sleep.target" "suspend-then-hibernate.target" ];
script =
''
/run/current-system/systemd/bin/systemctl try-restart --no-block post-resume.target
${cfg.resumeCommands}
${cfg.powerUpCommands}
'';
serviceConfig.Type = "oneshot";
};
};
}