wayland: use AtomicUsize for SerialCounter

src/wayland/mod.rs

@@ -12,7 +12,7 @@
 //!   destroy the global at all, you don't need to bother keeping the
 //!   `Global` around.
 
-use std::sync::Mutex;
+use std::sync::atomic::{AtomicUsize, Ordering};
 
 pub mod compositor;
 pub mod output;
@@ -20,14 +20,12 @@ pub mod seat;
 pub mod shell;
 pub mod shm;
 
-lazy_static! {
 /// A global SerialCounter for use in your compositor.
 ///
 /// Is is also used internally by some parts of Smithay.
-    pub static ref SERIAL_COUNTER: SerialCounter = SerialCounter {
-        serial: Mutex::new(0)
+pub static SERIAL_COUNTER: SerialCounter = SerialCounter {
+    serial: AtomicUsize::new(0),
 };
-}
 
 /// A counter for generating serials, for use in the client protocol
 ///
@@ -39,14 +37,12 @@ lazy_static! {
 /// as needed.
 pub struct SerialCounter {
     // TODO: replace with an AtomicU32 when stabilized
-    serial: Mutex<u32>,
+    serial: AtomicUsize,
 }
 
 impl SerialCounter {
     /// Retrieve the next serial from the counter
     pub fn next_serial(&self) -> u32 {
-        let guard = self.serial.lock().unwrap();
-        guard.wrapping_add(1);
-        *guard
+        self.serial.fetch_add(1, Ordering::AcqRel) as u32
     }
 }