[refactor] remove in_timer_list flag in axtask

modules/axtask/src/task.rs

@@ -50,9 +50,6 @@ pub struct TaskInner {
 
     /// Mark whether the task is in the wait queue.
     in_wait_queue: AtomicBool,
-    /// Mark whether the task is in the timer list.
-    #[cfg(feature = "irq")]
-    in_timer_list: AtomicBool,
     /// A ticket ID used to identify the timer event.
     /// Incremented by 1 each time the timer event is triggered or expired.
     #[cfg(feature = "irq")]
@@ -200,8 +197,6 @@ impl TaskInner {
             cpumask: SpinNoIrq::new(CpuMask::full()),
             in_wait_queue: AtomicBool::new(false),
             #[cfg(feature = "irq")]
-            in_timer_list: AtomicBool::new(false),
-            #[cfg(feature = "irq")]
             timer_ticket_id: AtomicU64::new(0),
             on_cpu: AtomicBool::new(false),
             prev_task_on_cpu_ptr: AtomicPtr::new(core::ptr::null_mut()),
@@ -297,18 +292,6 @@ impl TaskInner {
         self.in_wait_queue.store(in_wait_queue, Ordering::Release);
     }
 
-    #[inline]
-    #[cfg(feature = "irq")]
-    pub(crate) fn in_timer_list(&self) -> bool {
-        self.in_timer_list.load(Ordering::Acquire)
-    }
-
-    #[inline]
-    #[cfg(feature = "irq")]
-    pub(crate) fn set_in_timer_list(&self, in_timer_list: bool) {
-        self.in_timer_list.store(in_timer_list, Ordering::Release);
-    }
-
     /// Returns current available timer ticket ID.
     #[inline]
     #[cfg(feature = "irq")]

modules/axtask/src/timers.rs

@@ -17,18 +17,16 @@ struct TaskWakeupEvent {
 
 impl TimerEvent for TaskWakeupEvent {
     fn callback(self, _now: TimeValue) {
-        // Ignore the timer event if the task is not in the timer list.
-        // timeout was set but not triggered (wake up by `WaitQueue::notify()`).
+        // Ignore the timer event if timeout was set but not triggered
+        // (wake up by `WaitQueue::notify()`).
         // Judge if this timer event is still valid by checking the ticket ID.
-        if !self.task.in_timer_list() || self.task.timer_ticket() != self.ticket_id {
+        if self.task.timer_ticket() != self.ticket_id {
             // The task is not in the timer list or the ticket ID is not matched.
             // Just ignore this timer event and return.
             return;
         }
 
         // Timer ticket match.
-        // Mark the task as not in the timer list.
-        self.task.set_in_timer_list(false);
         // Timer event is triggered, expire the ticket ID.
         self.task.timer_ticket_expire_one();
         select_run_queue::<NoOp>(self.task.clone()).unblock_task(self.task, true)
@@ -37,7 +35,6 @@ impl TimerEvent for TaskWakeupEvent {
 
 pub fn set_alarm_wakeup(deadline: TimeValue, task: AxTaskRef) {
     TIMER_LIST.with_current(|timer_list| {
-        task.set_in_timer_list(true);
         timer_list.set(
             deadline,
             TaskWakeupEvent {

modules/axtask/src/wait_queue.rs

@@ -47,7 +47,9 @@ impl WaitQueue {
         }
     }
 
-    fn cancel_events(&self, curr: CurrentTask) {
+    /// Cancel events by removing the task from the wait queue.
+    /// If `from_timer_list` is true, the task should be removed from the timer list.
+    fn cancel_events(&self, curr: CurrentTask, from_timer_list: bool) {
         // A task can be wake up only one events (timer or `notify()`), remove
         // the event from another queue.
         if curr.in_wait_queue() {
@@ -56,9 +58,10 @@ impl WaitQueue {
             wq_locked.retain(|t| !curr.ptr_eq(t));
             curr.set_in_wait_queue(false);
         }
+        // Try to cancel a timer event from timer lists.
+        // Just mark task's current timer ticket ID as expired.
         #[cfg(feature = "irq")]
-        if curr.in_timer_list() {
-            curr.set_in_timer_list(false);
+        if from_timer_list {
             curr.timer_ticket_expire_one();
             // TODO:
             // this task is still not removed from timer list of target CPU,
@@ -91,7 +94,7 @@ impl WaitQueue {
         let mut rq = current_run_queue::<NoPreemptIrqSave>();
         self.push_to_wait_queue();
         rq.blocked_resched();
-        self.cancel_events(crate::current());
+        self.cancel_events(crate::current(), false);
     }
 
     /// Blocks the current task and put it into the wait queue, until the given
@@ -128,7 +131,7 @@ impl WaitQueue {
 
             rq.blocked_resched();
         }
-        self.cancel_events(crate::current());
+        self.cancel_events(crate::current(), false);
     }
 
     /// Blocks the current task and put it into the wait queue, until other tasks
@@ -149,7 +152,10 @@ impl WaitQueue {
         rq.blocked_resched();
 
         let timeout = curr.in_wait_queue(); // still in the wait queue, must have timed out
-        self.cancel_events(curr);
+
+        // If `timeout` is true, the task is still in the wait queue,
+        // which means timer event is triggered and the task has been removed from timer list.
+        self.cancel_events(curr, !timeout);
         timeout
     }
 
@@ -196,7 +202,7 @@ impl WaitQueue {
 
             rq.blocked_resched()
         }
-        self.cancel_events(curr);
+        self.cancel_events(curr, !timeout);
         timeout
     }