nixos/switch-to-configuration: remove explicit tmpfiles invocation

nixos/doc/manual/development/what-happens-during-a-system-switch.chapter.md

@@ -37,7 +37,6 @@ of actions is always the same:
 - Forget about the failed state of units (`systemctl reset-failed`)
 - Reload systemd (`systemctl daemon-reload`)
 - Reload systemd user instances (`systemctl --user daemon-reload`)
-- Set up tmpfiles (`systemd-tmpfiles --create`)
 - Reload units (`systemctl reload`)
 - Restart units (`systemctl restart`)
 - Start units (`systemctl start`)

nixos/modules/system/activation/switch-to-configuration.pl

@@ -889,10 +889,6 @@ while (my $f = <$list_active_users>) {
 
 close($list_active_users) || die("Unable to close the file handle to loginctl");
 
-# Set the new tmpfiles
-print STDERR "setting up tmpfiles\n";
-system("$new_systemd/bin/systemd-tmpfiles", "--create", "--remove", "--exclude-prefix=/dev") == 0 or $res = 3;
-
 # Before reloading we need to ensure that the units are still active. They may have been
 # deactivated because one of their requirements got stopped. If they are inactive
 # but should have been reloaded, the user probably expects them to be started.

nixos/modules/system/boot/systemd/tmpfiles.nix

@@ -150,6 +150,12 @@ in
       "systemd-tmpfiles-setup.service"
     ];
 
+    # Allow systemd-tmpfiles to be restarted by switch-to-configuration.
+    systemd.services."systemd-tmpfiles-setup" = {
+      unitConfig.RefuseManualStop = "no";
+      restartTriggers = [ "${config.environment.etc."tmpfiles.d".source}" ];
+    };
+
     environment.etc = {
       "tmpfiles.d".source = (pkgs.symlinkJoin {
         name = "tmpfiles.d";