Start timeout in kernel executor

tornado-kernel/src/task/executor.rs

@@ -30,6 +30,8 @@ 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/handler.rs

@@ -72,7 +72,7 @@ pub extern "C" fn supervisor_timer(trap_frame: &mut TrapFrame) -> *mut TrapFrame
     // 保存当前任务的上下文
     if let Some(handle) = current_task() {
         KernelHartInfo::save_task_context(handle, trap_frame);
-        panic!("Current task: {:x?}", handle);
+        println!("Current task: {:x?}", handle);
     }
 
     trap_frame

tornado-kernel/src/trap/mod.rs

@@ -2,6 +2,7 @@ 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;
 
-fn set_next_timeout() {
+pub fn set_next_timeout() {
     set_timer(time::read() + INTERVAL);
 }