io_uring: remove unnecessary interior mutability

src/io_uring/ops/async_cancel.rs

@@ -6,33 +6,28 @@ use {
         },
         utils::errorfmt::ErrorFmt,
     },
-    std::cell::Cell,
     uapi::c,
 };
 
+#[derive(Default)]
 pub struct AsyncCancelTask {
-    id: Cell<u64>,
-    target: Cell<u64>,
+    id: u64,
+    target: u64,
 }
 
 impl IoUringData {
     pub fn cancel_task_in_kernel(&self, target: u64) {
-        let task = self.cached_cancels.pop().unwrap_or_else(|| {
-            Box::new(AsyncCancelTask {
-                id: Cell::new(0),
-                target: Cell::new(0),
-            })
-        });
         let id = self.id_raw();
-        task.id.set(id);
-        task.target.set(target);
+        let mut task = self.cached_cancels.pop().unwrap_or_default();
+        task.id = id;
+        task.target = target;
         self.schedule(task);
     }
 }
 
 unsafe impl Task for AsyncCancelTask {
     fn id(&self) -> u64 {
-        self.id.get()
+        self.id
     }
 
     fn complete(self: Box<Self>, ring: &IoUringData, res: i32) {
@@ -46,7 +41,7 @@ unsafe impl Task for AsyncCancelTask {
 
     fn encode(&self, sqe: &mut io_uring_sqe) {
         sqe.opcode = IORING_OP_ASYNC_CANCEL;
-        sqe.u2.addr = self.target.get();
+        sqe.u2.addr = self.target;
     }
 
     fn is_cancel(&self) -> bool {