Merge pull request NixOS#209506 from Izorkin/update-dhcpcd-exit-hook

nixos/dhcpcd: optimize exitHook
risicle · Feb 27, 2024 · f9477e3 · f9477e3
2 parents 3beaece + 1293f04
commit f9477e3
Showing 1 changed file with 19 additions and 13 deletions.
diff --git a/nixos/modules/services/networking/dhcpcd.nix b/nixos/modules/services/networking/dhcpcd.nix
@@ -13,6 +13,8 @@ let
  enableDHCP = config.networking.dhcpcd.enable &&
  (config.networking.useDHCP || any (i: i.useDHCP == true) interfaces);
 
+ enableNTPService = (config.services.ntp.enable || config.services.ntpd-rs.enable || config.services.openntpd.enable || config.services.chrony.enable);
+
  # Don't start dhcpcd on explicitly configured interfaces or on
  # interfaces that are part of a bridge, bond or sit device.
  ignoredInterfaces =
@@ -89,20 +91,22 @@ let
  ${cfg.extraConfig}
  '';
 
- exitHook = pkgs.writeText "dhcpcd.exit-hook"
- ''
+ exitHook = pkgs.writeText "dhcpcd.exit-hook" ''
+ ${optionalString enableNTPService ''
  if [ "$reason" = BOUND -o "$reason" = REBOOT ]; then
- # Restart ntpd. We need to restart it to make sure that it
- # will actually do something: if ntpd cannot resolve the
- # server hostnames in its config file, then it will never do
- # anything ever again ("couldn't resolve ..., giving up on
- # it"), so we silently lose time synchronisation. This also
- # applies to openntpd.
- /run/current-system/systemd/bin/systemctl try-reload-or-restart ntpd.service openntpd.service chronyd.service ntpd-rs.service || true
+ # Restart ntpd. We need to restart it to make sure that it will actually do something:
+ # if ntpd cannot resolve the server hostnames in its config file, then it will never do
+ # anything ever again ("couldn't resolve ..., giving up on it"), so we silently lose
+ # time synchronisation. This also applies to openntpd.
+ ${optionalString config.services.ntp.enable "/run/current-system/systemd/bin/systemctl try-reload-or-restart ntpd.service || true"}
+ ${optionalString config.services.ntpd-rs.enable "/run/current-system/systemd/bin/systemctl try-reload-or-restart ntpd-rs.service || true"}
+ ${optionalString config.services.openntpd.enable "/run/current-system/systemd/bin/systemctl try-reload-or-restart openntpd.service || true"}
+ ${optionalString config.services.chrony.enable "/run/current-system/systemd/bin/systemctl try-reload-or-restart chronyd.service || true"}
  fi
+ ''}
 
-  ${cfg.runHook}
-  '';
+ ${cfg.runHook}
+ '';
 
 in
 
@@ -232,7 +236,7 @@ in
  wants = [ "network.target" ];
  before = [ "network-online.target" ];
 
- restartTriggers = [ exitHook ];
+ restartTriggers = optional (enableNTPService || cfg.runHook != "") [ exitHook ];
 
  # Stopping dhcpcd during a reconfiguration is undesirable
  # because it brings down the network interfaces configured by
@@ -261,7 +265,9 @@ in
 
  environment.systemPackages = [ dhcpcd ];
 
- environment.etc."dhcpcd.exit-hook".source = exitHook;
+ environment.etc."dhcpcd.exit-hook" = mkIf (enableNTPService || cfg.runHook != "") {
+ source = exitHook;
+ };
 
  powerManagement.resumeCommands = mkIf config.systemd.services.dhcpcd.enable
  ''