switch-to-configuration-ng: Reload when ExecReload changes (#512578) (c523a578) · Commits · nix / nixpkgs

nixos/doc/manual/release-notes/rl-2605.section.md

+2 −0

Original line number	Diff line number	Diff line
		@@ -347,6 +347,8 @@ See <https://github.com/NixOS/nixpkgs/issues/481673>.

		<!-- To avoid merge conflicts, consider adding your item at an arbitrary place in the list instead. -->

		- `switch-to-configuration` now reloads a service instead of restarting it when the only change to its unit is `ExecReload=`, and takes no action when `ExecReload=` is removed. Previously both cases triggered a restart.

		- [`hardware.nvidia.branch`](#opt-hardware.nvidia.branch) was added to select the NVIDIA driver branch; setting [`hardware.nvidia.package`](#opt-hardware.nvidia.package) overrides this.

		- The NixOS NVIDIA module wiring has been updated to match the new `nvidia-x11` output layout.

pkgs/by-name/sw/switch-to-configuration-ng/src/main.rs

+153 −9

Original line number	Diff line number	Diff line
		@@ -489,9 +489,10 @@ enum UnitComparison {

		// Compare the contents of two unit files and return whether the unit needs to be restarted or
		// reloaded. If the units differ, the service is restarted unless the only difference is
		// `X-Reload-Triggers` in the `Unit` section. If this is the only modification, the unit is
		// reloaded instead of restarted. If the only difference is `Options` in the `[Mount]` section, the
		// unit is reloaded rather than restarted.
		// `X-Reload-Triggers` in the `[Unit]` section, `Options` in the `[Mount]` section, or `ExecReload`
		// in the `[Service]` section, in which case the unit is reloaded rather than restarted. Removing
		// `ExecReload` is treated as a no-op since the running process is unaffected and the new unit can
		// no longer be reloaded.
		fn compare_units(current_unit: &UnitInfo, new_unit: &UnitInfo) -> UnitComparison {
		let mut ret = UnitComparison::Equal;

		@@ -532,6 +533,13 @@ fn compare_units(current_unit: &UnitInfo, new_unit: &UnitInfo) -> UnitComparison
		}
		}
		continue; // check the next section
		} else if section_name == "Service"
		&& section_val.len() == 1
		&& section_val.contains_key("ExecReload")
		{
		// Dropping ExecReload does not affect the running process and the
		// new unit can no longer be reloaded, so there is nothing to do.
		continue;
		} else {
		return UnitComparison::UnequalNeedsRestart;
		}
		@@ -562,6 +570,11 @@ fn compare_units(current_unit: &UnitInfo, new_unit: &UnitInfo) -> UnitComparison
		if section_name == "Unit" && unit_section_ignores.contains_key(ini_key.as_str()) {
		continue;
		}
		// Dropping ExecReload does not affect the running process and the
		// new unit can no longer be reloaded, so there is nothing to do.
		if section_name == "Service" && ini_key == "ExecReload" {
		continue;
		}
		return UnitComparison::UnequalNeedsRestart;
		};

		@@ -576,6 +589,12 @@ fn compare_units(current_unit: &UnitInfo, new_unit: &UnitInfo) -> UnitComparison
		}
		}

		// If this is a service unit, check if it was only `ExecReload`
		if section_name == "Service" && ini_key == "ExecReload" {
		ret = UnitComparison::UnequalNeedsReload;
		continue;
		}

		// If this is a mount unit, check if it was only `Options`
		if section_name == "Mount" && ini_key == "Options" {
		ret = UnitComparison::UnequalNeedsReload;
		@@ -598,6 +617,12 @@ fn compare_units(current_unit: &UnitInfo, new_unit: &UnitInfo) -> UnitComparison
		return UnitComparison::UnequalNeedsRestart;
		}
		}
		} else if section_name == "Service"
		&& ini_cmp.len() == 1
		&& ini_cmp.contains_key("ExecReload")
		{
		ret = UnitComparison::UnequalNeedsReload;
		continue;
		} else {
		return UnitComparison::UnequalNeedsRestart;
		}
		@@ -606,7 +631,9 @@ fn compare_units(current_unit: &UnitInfo, new_unit: &UnitInfo) -> UnitComparison

		// A section was introduced that was missing in the previous unit
		if !section_cmp.is_empty() {
		if section_cmp.keys().len() == 1 && section_cmp.contains_key("Unit") {
		if section_cmp.keys().len() == 1 {
		// Dispatch on which section is actually new.
		if section_cmp.contains_key("Unit") {
		if let Some(new_unit_unit) = new_unit.get("Unit") {
		for ini_key in new_unit_unit.keys() {
		if !unit_section_ignores.contains_key(ini_key.as_str()) {
		@@ -616,6 +643,17 @@ fn compare_units(current_unit: &UnitInfo, new_unit: &UnitInfo) -> UnitComparison
		}
		}
		}
		} else if section_cmp.contains_key("Service") {
		if let Some(new_unit_service) = new_unit.get("Service") {
		if new_unit_service.len() == 1 && new_unit_service.contains_key("ExecReload") {
		ret = UnitComparison::UnequalNeedsReload;
		} else {
		return UnitComparison::UnequalNeedsRestart;
		}
		}
		} else {
		return UnitComparison::UnequalNeedsRestart;
		}
		} else {
		return UnitComparison::UnequalNeedsRestart;
		}
		@@ -2623,6 +2661,112 @@ invalid
		) == super::UnitComparison::UnequalNeedsReload
		);

		assert!(
		super::compare_units(
		&HashMap::from([]),
		&HashMap::from([(
		"Service".to_string(),
		HashMap::from([("ExecReload".to_string(), vec!["foobar".to_string()])])
		)])
		) == super::UnitComparison::UnequalNeedsReload
		);

		assert!(
		super::compare_units(
		&HashMap::from([(
		"Service".to_string(),
		HashMap::from([("ExecReload".to_string(), vec!["foobar".to_string()])])
		)]),
		&HashMap::from([(
		"Service".to_string(),
		HashMap::from([("ExecReload".to_string(), vec!["barfoo".to_string()])])
		)])
		) == super::UnitComparison::UnequalNeedsReload
		);

		// New [Service] section while [Unit] already existed: must inspect
		// the [Service] section, not the (unchanged) [Unit] one.
		assert!(
		super::compare_units(
		&HashMap::from([(
		"Unit".to_string(),
		HashMap::from([("Description".to_string(), vec!["x".to_string()])])
		)]),
		&HashMap::from([
		(
		"Unit".to_string(),
		HashMap::from([("Description".to_string(), vec!["x".to_string()])])
		),
		(
		"Service".to_string(),
		HashMap::from([("ExecStart".to_string(), vec!["y".to_string()])])
		),
		]),
		) == super::UnitComparison::UnequalNeedsRestart
		);
		assert!(
		super::compare_units(
		&HashMap::from([(
		"Unit".to_string(),
		HashMap::from([("Description".to_string(), vec!["x".to_string()])])
		)]),
		&HashMap::from([
		(
		"Unit".to_string(),
		HashMap::from([("Description".to_string(), vec!["x".to_string()])])
		),
		(
		"Service".to_string(),
		HashMap::from([("ExecReload".to_string(), vec!["y".to_string()])])
		),
		]),
		) == super::UnitComparison::UnequalNeedsReload
		);

		// ExecReload removed: running process is unaffected and the new
		// unit cannot be reloaded, so no action is needed.
		assert!(
		super::compare_units(
		&HashMap::from([(
		"Service".to_string(),
		HashMap::from([
		("ExecStart".to_string(), vec!["x".to_string()]),
		("ExecReload".to_string(), vec!["y".to_string()]),
		])
		)]),
		&HashMap::from([(
		"Service".to_string(),
		HashMap::from([("ExecStart".to_string(), vec!["x".to_string()])])
		)]),
		) == super::UnitComparison::Equal
		);
		assert!(
		super::compare_units(
		&HashMap::from([(
		"Service".to_string(),
		HashMap::from([("ExecReload".to_string(), vec!["y".to_string()])])
		)]),
		&HashMap::from([]),
		) == super::UnitComparison::Equal
		);

		// ExecReload added to an existing [Service] section
		assert!(
		super::compare_units(
		&HashMap::from([(
		"Service".to_string(),
		HashMap::from([("ExecStart".to_string(), vec!["x".to_string()])])
		)]),
		&HashMap::from([(
		"Service".to_string(),
		HashMap::from([
		("ExecStart".to_string(), vec!["x".to_string()]),
		("ExecReload".to_string(), vec!["y".to_string()]),
		])
		)]),
		) == super::UnitComparison::UnequalNeedsReload
		);

		assert!(
		super::compare_units(
		&HashMap::from([(