Refresh lid observations before rendering after resume

compositor/src/backends/direct.rs

@@ -6,6 +6,7 @@ use std::path::Path;
 use std::time::{Duration, Instant};
 
 mod capture;
+mod lid;
 mod output_power;
 mod planes;
 mod redraw;
@@ -53,7 +54,8 @@ use crate::render::{frame_effect_metrics, sampled_output_elements};
 pub struct DirectBackendState {
     pub session: LibSeatSession,
     pub active: bool,
-    lid_closed: bool,
+    lid: lid::LidState,
+    lid_reader: lid::Reader,
     topology: Topology,
     pub(crate) low_power: bool,
     devices: HashMap<DrmNode, DirectDevice>,
@@ -69,7 +71,7 @@ pub struct DirectBackendState {
 
 impl DirectBackendState {
     fn can_render(&self) -> bool {
-        self.active && !self.topology.reconciling
+        self.active && !self.topology.reconciling && !self.lid.pending()
     }
 
     pub(crate) fn dump_scheduling_metrics(&self) {
@@ -239,10 +241,12 @@ pub fn init(event_loop: &mut EventLoop<Ferese>, state: &mut Ferese) -> Result<()
         libinput_context.suspend();
     }
 
+    let lid_reader = lid::Reader::start(state)?;
     state.direct_backend = Some(DirectBackendState {
         session,
         active: session_active,
-        lid_closed: initial_lid_closed(),
+        lid: lid::LidState::default(),
+        lid_reader,
         topology: Topology::default(),
         low_power: super::power::low_power(false, super::power::battery_percent()),
         devices: HashMap::new(),
@@ -263,8 +267,7 @@ pub fn init(event_loop: &mut EventLoop<Ferese>, state: &mut Ferese) -> Result<()
         .topology
         .devices
         .insert(primary_path, Default::default());
-    reconcile_outputs(state, false);
-    sync_battery_timer(state);
+    lid::request_refresh(state, false);
 
     event_loop
         .handle()
@@ -291,6 +294,10 @@ pub fn init(event_loop: &mut EventLoop<Ferese>, state: &mut Ferese) -> Result<()
                 let handle = state.loop_handle.clone();
                 if let Some(backend) = state.direct_backend.as_mut() {
                     backend.active = false;
+                    backend.lid.pause();
+                    if let Some(token) = backend.lid_reader.deadline.take() {
+                        handle.remove(token);
+                    }
                     backend.topology.dirty = true;
                     if let Some(token) = backend.topology.retry_timer.take() {
                         handle.remove(token);
@@ -336,12 +343,8 @@ pub fn init(event_loop: &mut EventLoop<Ferese>, state: &mut Ferese) -> Result<()
 
                 let seat = state.seat.clone();
                 state.idle_notifier_state.notify_activity(&seat);
-                reconcile_outputs(state, true);
-                sync_battery_timer(state);
-                state.reset_animation_clock();
-                tracing::info!("direct session activated");
-                state.lock_input_activity();
-                render_all(state);
+                lid::request_refresh(state, true);
+                tracing::info!("direct session reacquired; refreshing external state");
             }
         })?;
     event_loop.handle().insert_source(udev_backend, |event, _, state| {
@@ -468,7 +471,7 @@ pub(crate) fn validate_live_outputs(state: &Ferese, profiles: &[OutputProfile])
     let mut usable = 0;
     for device in backend.devices.values() {
         let mut scan = select_outputs(&device.drm, profiles, backend.low_power).map_err(|e| e.to_string())?;
-        apply_lid_policy(&mut scan, backend.lid_closed);
+        apply_lid_policy(&mut scan, backend.lid.closed());
         usable += scan.selections.len();
     }
     if usable == 0 {
@@ -864,22 +867,19 @@ pub(crate) fn set_lid_closed(state: &mut Ferese, closed: bool) {
     let Some(backend) = state.direct_backend.as_mut() else {
         return;
     };
-    if backend.lid_closed == closed {
-        return;
-    }
-    backend.lid_closed = closed;
+    // Even an unchanged switch observation supersedes an in-flight DBus read.
+    if backend.lid.observe(closed) {
         tracing::info!(closed, "laptop lid state changed");
         reconcile_outputs(state, false);
+    }
 }
 
-fn initial_lid_closed() -> bool {
-    std::fs::read_dir("/proc/acpi/button/lid")
-        .ok()
-        .into_iter()
-        .flatten()
-        .filter_map(Result::ok)
-        .filter_map(|entry| std::fs::read_to_string(entry.path().join("state")).ok())
-        .any(|state| state.split_whitespace().last() == Some("closed"))
+pub(crate) fn system_resumed(state: &mut Ferese) {
+    if state.direct_backend.as_ref().is_some_and(|backend| backend.active) {
+        let seat = state.seat.clone();
+        state.idle_notifier_state.notify_activity(&seat);
+    }
+    lid::request_refresh(state, true);
 }
 
 fn internal_connector(interface: connector::Interface) -> bool {
@@ -1122,7 +1122,10 @@ fn rescan_device(state: &mut Ferese, node: DrmNode) -> Result<bool, ()> {
         }
     };
 
-    let lid_closed = state.direct_backend.as_ref().is_some_and(|backend| backend.lid_closed);
+    let lid_closed = state
+        .direct_backend
+        .as_ref()
+        .is_some_and(|backend| backend.lid.closed());
     apply_lid_policy(&mut scan, lid_closed);
     device.connected_outputs = scan.connected_outputs;
     let mut complete = true;
@@ -1562,6 +1565,7 @@ fn deliver_frame_callbacks(state: &mut Ferese, node: DrmNode, crtc: crtc::Handle
     output.callback_timer = None;
     if !backend.active
         || backend.topology.reconciling
+        || backend.lid.pending()
         || !device.drm.is_active()
         || !output.power.can_render()
         || state.session_lock.sleeping

compositor/src/backends/direct/lid.rs

@@ -0,0 +1,304 @@
+//! Resume reads are asynchronous; newer switch events win over old replies.
+use std::sync::mpsc;
+
+use super::*;
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub(super) struct Probe {
+    serial: u64,
+    revision: u64,
+    reactivate: bool,
+}
+
+#[derive(Default)]
+pub(super) struct LidState {
+    value: Option<bool>,
+    revision: u64,
+    serial: u64,
+    pending: Option<Probe>,
+}
+
+impl LidState {
+    pub fn closed(&self) -> bool {
+        self.value == Some(true)
+    }
+    pub fn pending(&self) -> bool {
+        self.pending.is_some()
+    }
+
+    pub fn observe(&mut self, closed: bool) -> bool {
+        let changed = self.value != Some(closed);
+        self.value = Some(closed);
+        self.revision = self.revision.wrapping_add(1);
+        changed
+    }
+
+    fn begin(&mut self, reactivate: bool) -> Probe {
+        self.serial = self.serial.wrapping_add(1);
+        let probe = Probe {
+            serial: self.serial,
+            revision: self.revision,
+            reactivate: reactivate || self.pending.is_some_and(|pending| pending.reactivate),
+        };
+        self.pending = Some(probe);
+        probe
+    }
+
+    fn complete(&mut self, probe: Probe, value: Option<bool>) -> Option<bool> {
+        if self.pending != Some(probe) {
+            return None;
+        }
+
+        self.pending = None;
+        if probe.revision == self.revision
+            && let Some(value) = value
+        {
+            self.observe(value);
+        }
+        Some(probe.reactivate)
+    }
+
+    pub fn pause(&mut self) {
+        self.pending = None;
+    }
+}
+
+pub(super) struct Reader {
+    requests: mpsc::Sender<Probe>,
+    pub deadline: Option<RegistrationToken>,
+}
+
+fn read_logind(connection: &zbus::blocking::Connection) -> zbus::Result<bool> {
+    // A direct Get avoids retaining a property cache across suspend.
+    let value: zbus::zvariant::OwnedValue = connection
+        .call_method(
+            Some("org.freedesktop.login1"),
+            "/org/freedesktop/login1",
+            Some("org.freedesktop.DBus.Properties"),
+            "Get",
+            &("org.freedesktop.login1.Manager", "LidClosed"),
+        )?
+        .body()
+        .deserialize()?;
+    bool::try_from(value).map_err(Into::into)
+}
+
+fn read_acpi() -> Option<bool> {
+    let mut state = None;
+    for entry in std::fs::read_dir("/proc/acpi/button/lid").ok()?.flatten() {
+        let Ok(text) = std::fs::read_to_string(entry.path().join("state")) else {
+            continue;
+        };
+        match text.split_whitespace().last() {
+            Some("closed") => return Some(true),
+            Some("open") => state = Some(false),
+            _ => {}
+        }
+    }
+    state
+}
+
+impl Reader {
+    pub fn start(state: &Ferese) -> Result<Self, Box<dyn Error>> {
+        let (requests, receiver) = mpsc::channel::<Probe>();
+        let (replies, events) = smithay::reexports::calloop::channel::channel();
+        state.loop_handle.insert_source(events, |event, _, state| {
+            if let smithay::reexports::calloop::channel::Event::Msg((probe, value)) = event {
+                complete_refresh(state, probe, value);
+            }
+        })?;
+
+        std::thread::Builder::new()
+            .name("ferese-lid-reader".into())
+            .spawn(move || {
+                while let Ok(mut probe) = receiver.recv() {
+                    for newer in receiver.try_iter() {
+                        probe = newer;
+                    }
+                    let value = zbus::blocking::connection::Builder::system()
+                        .and_then(|builder| builder.method_timeout(Duration::from_secs(2)).build())
+                        .and_then(|connection| read_logind(&connection))
+                        .ok()
+                        .or_else(read_acpi);
+                    if replies.send((probe, value)).is_err() {
+                        break;
+                    }
+                }
+            })?;
+
+        Ok(Self {
+            requests,
+            deadline: None,
+        })
+    }
+}
+
+pub(super) fn request_refresh(state: &mut Ferese, reactivate: bool) {
+    let Some(backend) = state.direct_backend.as_mut() else {
+        return;
+    };
+    if !backend.active {
+        backend.topology.dirty = true;
+        return;
+    }
+
+    if let Some(token) = backend.lid_reader.deadline.take() {
+        state.loop_handle.remove(token);
+    }
+    // A timer that fires while readiness is gated would otherwise leave a
+    // stale registration token on an unchanged output.
+    for device in backend.devices.values_mut() {
+        for output in device.outputs.values_mut() {
+            cancel_output_timers(&state.loop_handle, output);
+        }
+    }
+    let probe = backend.lid.begin(reactivate);
+    let sent = backend.lid_reader.requests.send(probe).is_ok();
+    let timer = state
+        .loop_handle
+        .insert_source(Timer::from_duration(Duration::from_secs(3)), move |_, _, state| {
+            if let Some(backend) = state.direct_backend.as_mut() {
+                backend.lid_reader.deadline = None;
+            }
+            tracing::warn!("lid refresh deadline elapsed; retaining the latest observed state");
+            complete_refresh(state, probe, None);
+            TimeoutAction::Drop
+        });
+
+    if sent && let Ok(token) = timer {
+        state.direct_backend.as_mut().unwrap().lid_reader.deadline = Some(token);
+    } else {
+        if let Ok(token) = timer {
+            state.loop_handle.remove(token);
+        }
+        complete_refresh(state, probe, None);
+    }
+}
+
+fn complete_refresh(state: &mut Ferese, probe: Probe, value: Option<bool>) {
+    let Some(backend) = state.direct_backend.as_mut() else {
+        return;
+    };
+    let Some(reactivate) = backend.lid.complete(probe, value) else {
+        return;
+    };
+    if let Some(token) = backend.lid_reader.deadline.take() {
+        state.loop_handle.remove(token);
+    }
+    if !backend.active {
+        return;
+    }
+
+    // Waking a locked session may request redraws. Hold them until the fresh
+    // device/connector snapshot has been reconciled.
+    backend.topology.reconciling = true;
+    state.reset_animation_clock();
+    state.lock_input_activity();
+    state.direct_backend.as_mut().unwrap().topology.reconciling = false;
+    reconcile_outputs(state, reactivate);
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    #[ignore = "requires dbus-daemon and private test sockets"]
+    fn logind_reads_are_fresh_without_property_change_signals() {
+        use std::io::{BufRead, BufReader};
+        use std::process::{Command, Stdio};
+        use std::sync::Arc;
+        use std::sync::atomic::{AtomicBool, Ordering};
+
+        struct Bus(std::process::Child);
+        impl Drop for Bus {
+            fn drop(&mut self) {
+                let _ = self.0.kill();
+                let _ = self.0.wait();
+            }
+        }
+        struct Manager(Arc<AtomicBool>);
+        #[zbus::interface(name = "org.freedesktop.login1.Manager")]
+        impl Manager {
+            #[zbus(property)]
+            fn lid_closed(&self) -> bool {
+                self.0.load(Ordering::Relaxed)
+            }
+        }
+
+        let mut bus = Bus(Command::new("dbus-daemon")
+            .args(["--session", "--nofork", "--print-address=1"])
+            .stdout(Stdio::piped())
+            .spawn()
+            .unwrap());
+        let mut address = String::new();
+        BufReader::new(bus.0.stdout.take().unwrap())
+            .read_line(&mut address)
+            .unwrap();
+        let closed = Arc::new(AtomicBool::new(true));
+        let server = zbus::blocking::connection::Builder::address(address.trim())
+            .unwrap()
+            .name("org.freedesktop.login1")
+            .unwrap()
+            .serve_at("/org/freedesktop/login1", Manager(closed.clone()))
+            .unwrap()
+            .build()
+            .unwrap();
+        let client = zbus::blocking::connection::Builder::address(address.trim())
+            .unwrap()
+            .method_timeout(Duration::from_secs(1))
+            .build()
+            .unwrap();
+        assert!(read_logind(&client).unwrap());
+        closed.store(false, Ordering::Relaxed);
+        assert!(!read_logind(&client).unwrap());
+        server.release_name("org.freedesktop.login1").unwrap();
+        assert!(
+            read_logind(&client).is_err(),
+            "missing logind must not masquerade as an open lid"
+        );
+    }
+
+    #[test]
+    fn newer_input_wins_over_a_delayed_resume_read() {
+        let mut lid = LidState::default();
+        lid.observe(true);
+        let probe = lid.begin(true);
+        lid.observe(false);
+        assert_eq!(lid.complete(probe, Some(true)), Some(true));
+        assert!(!lid.closed());
+    }
+
+    #[test]
+    fn failed_reads_preserve_known_state_and_unknown_is_not_an_open_observation() {
+        let mut lid = LidState::default();
+        let probe = lid.begin(false);
+        lid.complete(probe, None);
+        assert_eq!(lid.value, None);
+        lid.observe(true);
+        let probe = lid.begin(true);
+        lid.complete(probe, None);
+        assert_eq!(lid.value, Some(true));
+    }
+
+    #[test]
+    fn pause_and_newer_resume_invalidate_old_replies() {
+        let mut lid = LidState::default();
+        let old = lid.begin(true);
+        lid.pause();
+        assert_eq!(lid.complete(old, Some(true)), None);
+        let current = lid.begin(true);
+        assert_eq!(lid.complete(old, Some(true)), None);
+        assert!(lid.pending());
+        assert_eq!(lid.complete(current, Some(false)), Some(true));
+        assert!(!lid.pending());
+    }
+
+    #[test]
+    fn system_wake_cannot_cancel_pending_session_reactivation() {
+        let mut lid = LidState::default();
+        lid.begin(true);
+        let probe = lid.begin(false);
+        assert_eq!(lid.complete(probe, Some(false)), Some(true));
+    }
+}

compositor/src/backends/direct/topology.rs

@@ -114,12 +114,15 @@ pub(super) fn reconcile_outputs(state: &mut Ferese, reactivate: bool) {
     let Some(backend) = state.direct_backend.as_mut() else {
         return;
     };
-    if !backend.topology.request(backend.active) {
+    if !backend.topology.request(backend.active && !backend.lid.pending()) {
         return;
     }
 
     backend.topology.reconciling = true;
     backend.topology.dirty = false;
+    if reactivate {
+        backend.presentation.values_mut().for_each(PresentationClock::reset_timing);
+    }
     if let Some(token) = backend.topology.retry_timer.take() {
         state.loop_handle.remove(token);
     }
@@ -198,6 +201,15 @@ pub(super) fn reconcile_outputs(state: &mut Ferese, reactivate: bool) {
             let device = state.direct_backend.as_mut().unwrap().devices.get_mut(&node).unwrap();
             device.drm.activate(true).map(|()| {
                 for (crtc, output) in &mut device.outputs {
+                    cancel_output_timers(&state.loop_handle, output);
+                    output.surface.reset_buffers();
+                    output.primary_commit = None;
+                    output.capture_texture = None;
+                    output.frame_pending = false;
+                    output.lock_frame_pending = false;
+                    output.power.suspended();
+                    state.display_presentation.remove_output(&output.output);
+
                     if let Err(error) = output.surface.clear().and_then(|()| output.surface.reset_state()) {
                         tracing::warn!(%error, ?node, ?crtc, "output reset failed; recreating output");
                         failed_outputs.push(*crtc);
@@ -291,6 +303,7 @@ pub(super) fn reconcile_outputs(state: &mut Ferese, reactivate: bool) {
         }
     }
 
+    state.refresh_idle_inhibition();
     sync_battery_timer(state);
     state.restore_output_focus();
     state.relayout();

compositor/src/main.rs

@@ -27,6 +27,7 @@ mod render;
 #[cfg(feature = "resize-metrics")]
 mod resize_metrics;
 mod resize_transaction;
+mod resume;
 mod session_lock;
 mod shell_control;
 mod stacking;
@@ -93,6 +94,7 @@ fn main() -> Result<(), Box<dyn Error>> {
     let mut state = Ferese::new(&mut event_loop, display, runtime)?;
     state.config_source = initial_source.filter(|source| source.len() <= 60 * 1024);
     theme::init(&mut event_loop, &mut state, candidate)?;
+    resume::init(&mut event_loop)?;
     overview::init_font_loader(&mut event_loop, &mut state)?;
     backends::init(launch.backend, &mut event_loop, &mut state)?;
     info!(socket = ?state.socket_name, backend = ?launch.backend, "Ferese is accepting Wayland clients");

compositor/src/resume.rs

@@ -0,0 +1,57 @@
+//! System wake is shared by hardware reconciliation and time-dependent UI state.
+use std::error::Error;
+use std::time::Duration;
+
+use calloop::EventLoop;
+use calloop::channel::{Event, channel};
+
+use crate::Ferese;
+
+pub(crate) fn init(event_loop: &mut EventLoop<Ferese>) -> Result<(), Box<dyn Error>> {
+    let (sender, receiver) = channel();
+    event_loop.handle().insert_source(receiver, |event, _, state| {
+        if let Event::Msg(()) = event {
+            crate::backends::direct::system_resumed(state);
+            state.refresh_theme();
+        }
+    })?;
+
+    std::thread::Builder::new()
+        .name("ferese-system-resume".into())
+        .spawn(move || {
+            let mut warned = false;
+            loop {
+                let monitor = || -> zbus::Result<bool> {
+                    let connection = zbus::blocking::connection::Builder::system()?
+                        .method_timeout(Duration::from_secs(2))
+                        .build()?;
+                    let proxy = zbus::blocking::Proxy::new(
+                        &connection,
+                        "org.freedesktop.login1",
+                        "/org/freedesktop/login1",
+                        "org.freedesktop.login1.Manager",
+                    )?;
+                    for message in proxy.receive_signal("PrepareForSleep")? {
+                        let (sleeping,): (bool,) = message.body().deserialize()?;
+                        if !sleeping && sender.send(()).is_err() {
+                            return Ok(false);
+                        }
+                    }
+                    Ok(true)
+                };
+
+                match monitor() {
+                    Ok(false) => break,
+                    Ok(true) => warned = false,
+                    Err(error) if !warned => {
+                        tracing::warn!(%error, "system resume monitor unavailable; retrying connection");
+                        warned = true;
+                    }
+                    Err(_) => {}
+                }
+                // Recovery only: a healthy listener blocks on DBus signals.
+                std::thread::sleep(Duration::from_secs(5));
+            }
+        })?;
+    Ok(())
+}

compositor/src/theme.rs

@@ -265,32 +265,6 @@ pub(crate) fn init(
     }
     paths.lock().unwrap().insert(PathBuf::from("/etc/localtime"));
     let wakeup = state.loop_signal.clone();
-    let resume_sender = sender.clone();
-    let resume_wakeup = wakeup.clone();
-    std::thread::Builder::new()
-        .name("ferese-theme-resume".into())
-        .spawn(move || {
-            let monitor = || -> zbus::Result<()> {
-                let connection = zbus::blocking::Connection::system()?;
-                let proxy = zbus::blocking::Proxy::new(
-                    &connection,
-                    "org.freedesktop.login1",
-                    "/org/freedesktop/login1",
-                    "org.freedesktop.login1.Manager",
-                )?;
-                for message in proxy.receive_signal("PrepareForSleep")? {
-                    let (sleeping,): (bool,) = message.body().deserialize()?;
-                    if !sleeping {
-                        let _ = resume_sender.try_send(());
-                        resume_wakeup.wakeup();
-                    }
-                }
-                Ok(())
-            };
-            if let Err(error) = monitor() {
-                tracing::warn!(%error, "theme resume monitor unavailable");
-            }
-        })?;
     let system_sender = sender.clone();
     let system_wakeup = wakeup.clone();
     std::thread::Builder::new()