Small fix

tornado-kernel/src/task/executor.rs

@@ -30,8 +30,7 @@ where
                 // poll our future and give it a waker
                 let mut context = Context::from_waker(&*waker);
                 // println!("Poll begin");
-                
-                crate::trap::set_next_timeout(); // 开始计时，如果运行超时，切换上下文
+
                 let ret = task.future.lock().as_mut().poll(&mut context);
                 // println!("Ret = {:?}", ret);
                 if let Poll::Pending = ret {

tornado-kernel/src/trap/mod.rs

@@ -2,7 +2,6 @@ mod handler;
 mod timer;
 
 pub use handler::TrapFrame;
-pub use timer::set_next_timeout;
 
 /// 初始化中断相关的子模块
 /// 

tornado-kernel/src/trap/timer.rs

@@ -11,7 +11,7 @@ pub fn init() {
 
 static INTERVAL: usize = 100000;
 
-pub fn set_next_timeout() {
+fn set_next_timeout() {
     set_timer(time::read() + INTERVAL);
 }