Add ThreadExt and clean up PosixThreadExt

kernel/src/thread/kernel_thread.rs

@@ -5,7 +5,7 @@ use ostd::{
     task::{Task, TaskOptions},
 };
 
-use super::{oops, status::ThreadStatus, Thread};
+use super::{oops, status::ThreadStatus, Thread, ThreadExt};
 use crate::{prelude::*, sched::priority::Priority};
 
 /// The inner data of a kernel thread.
@@ -77,7 +77,7 @@ impl ThreadOptions {
     /// Builds a new kernel thread and runs it immediately.
     pub fn spawn(self) -> Arc<Thread> {
         let task = self.build();
-        let thread = Thread::borrow_from_task(&task).clone();
+        let thread = task.as_thread().unwrap().clone();
         thread.run();
         thread
     }

kernel/src/thread/mod.rs

@@ -65,10 +65,7 @@ impl Thread {
     /// This function returns `None` if the current task is not associated with
     /// a thread, or if called within the bootstrap context.
     pub fn current() -> Option<Arc<Self>> {
-        Task::current()?
-            .data()
-            .downcast_ref::<Arc<Thread>>()
-            .cloned()
+        Task::current()?.as_thread().cloned()
     }
 
     /// Returns the task associated with this thread.
@@ -76,15 +73,6 @@ impl Thread {
         self.task.upgrade().unwrap()
     }
 
-    /// Gets the Thread from task's data.
-    ///
-    /// # Panics
-    ///
-    /// This method panics if the task is not a thread.
-    pub fn borrow_from_task(task: &Task) -> &Arc<Self> {
-        task.data().downcast_ref::<Arc<Thread>>().unwrap()
-    }
-
     /// Runs this thread at once.
     pub fn run(&self) {
         self.status.store(ThreadStatus::Running, Ordering::Release);
@@ -173,3 +161,15 @@ impl Thread {
         &*self.data
     }
 }
+
+/// An extension trait for [`Thread`]-like types.
+pub trait ThreadExt {
+    /// Returns the associated [`Thread`].
+    fn as_thread(&self) -> Option<&Arc<Thread>>;
+}
+
+impl ThreadExt for Task {
+    fn as_thread(&self) -> Option<&Arc<Thread>> {
+        self.data().downcast_ref::<Arc<Thread>>()
+    }
+}

kernel/src/thread/work_queue/worker.rs

@@ -11,8 +11,7 @@ use super::worker_pool::WorkerPool;
 use crate::{
     prelude::*,
     sched::priority::{Priority, PriorityRange},
-    thread::kernel_thread::ThreadOptions,
-    Thread,
+    thread::{kernel_thread::ThreadOptions, ThreadExt},
 };
 
 /// A worker thread. A `Worker` will attempt to retrieve unfinished
@@ -72,7 +71,7 @@ impl Worker {
     }
 
     pub(super) fn run(&self) {
-        let thread = Thread::borrow_from_task(&self.bound_task);
+        let thread = self.bound_task.as_thread().unwrap();
         thread.run();
     }
 

kernel/src/thread/work_queue/worker_pool.rs

@@ -17,8 +17,7 @@ use super::{simple_scheduler::SimpleScheduler, worker::Worker, WorkItem, WorkPri
 use crate::{
     prelude::*,
     sched::priority::{Priority, PriorityRange},
-    thread::kernel_thread::ThreadOptions,
-    Thread,
+    thread::{kernel_thread::ThreadOptions, ThreadExt},
 };
 
 /// A pool of workers.
@@ -83,7 +82,7 @@ impl LocalWorkerPool {
     fn add_worker(&self) {
         let worker = Worker::new(self.parent.clone(), self.cpu_id);
         self.workers.disable_irq().lock().push_back(worker.clone());
-        Thread::borrow_from_task(worker.bound_task()).run();
+        worker.bound_task().as_thread().unwrap().run();
     }
 
     fn remove_worker(&self) {
@@ -258,7 +257,7 @@ impl Monitor {
     }
 
     pub fn run(&self) {
-        Thread::borrow_from_task(&self.bound_task).run()
+        self.bound_task.as_thread().unwrap().run()
     }
 
     fn run_monitor_loop(self: &Arc<Self>) {