Remove KernelThreadExt

kernel/src/fs/mod.rs

@@ -26,7 +26,6 @@ use crate::{
         fs_resolver::FsPath,
     },
     prelude::*,
-    thread::kernel_thread::KernelThreadExt,
 };
 
 fn start_block_device(device_name: &str) -> Result<Arc<dyn BlockDevice>> {
@@ -39,7 +38,7 @@ fn start_block_device(device_name: &str) -> Result<Arc<dyn BlockDevice>> {
                 virtio_block_device.handle_requests();
             }
         };
-        crate::Thread::spawn_kernel_thread(crate::ThreadOptions::new(task_fn));
+        crate::ThreadOptions::new(task_fn).spawn();
         Ok(device)
     } else {
         return_errno_with_message!(Errno::ENOENT, "Device does not exist")

kernel/src/fs/pipe.rs

@@ -200,10 +200,7 @@ mod test {
     use super::*;
     use crate::{
         fs::utils::Channel,
-        thread::{
-            kernel_thread::{KernelThreadExt, ThreadOptions},
-            Thread,
-        },
+        thread::{kernel_thread::ThreadOptions, Thread},
     };
 
     #[derive(Clone, Copy, Debug, PartialEq, Eq)]
@@ -232,7 +229,7 @@ mod test {
         let signal_writer = Arc::new(AtomicBool::new(false));
         let signal_reader = signal_writer.clone();
 
-        let writer = Thread::spawn_kernel_thread(ThreadOptions::new(move || {
+        let writer = ThreadOptions::new(move || {
             let writer = writer_with_lock.lock().take().unwrap();
 
             if ordering == Ordering::ReadThenWrite {
@@ -244,9 +241,10 @@ mod test {
             }
 
             write(writer);
-        }));
+        })
+        .spawn();
 
-        let reader = Thread::spawn_kernel_thread(ThreadOptions::new(move || {
+        let reader = ThreadOptions::new(move || {
             let reader = reader_with_lock.lock().take().unwrap();
 
             if ordering == Ordering::WriteThenRead {
@@ -258,7 +256,8 @@ mod test {
             }
 
             read(reader);
-        }));
+        })
+        .spawn();
 
         writer.join();
         reader.join();

kernel/src/lib.rs

@@ -43,10 +43,7 @@ use sched::priority::PriorityRange;
 use crate::{
     prelude::*,
     sched::priority::Priority,
-    thread::{
-        kernel_thread::{KernelThreadExt, ThreadOptions},
-        Thread,
-    },
+    thread::{kernel_thread::ThreadOptions, Thread},
 };
 
 extern crate alloc;
@@ -89,10 +86,9 @@ pub fn main() {
     ostd::boot::smp::register_ap_entry(ap_init);
 
     // Spawn the first kernel thread on BSP.
-    Thread::spawn_kernel_thread(
     ThreadOptions::new(init_thread)
-            .priority(Priority::new(PriorityRange::new(PriorityRange::MAX))),
-    );
+        .priority(Priority::new(PriorityRange::new(PriorityRange::MAX)))
+        .spawn();
 }
 
 pub fn init() {
@@ -122,11 +118,10 @@ fn ap_init() {
     let cpu_id = preempt_guard.current_cpu();
     drop(preempt_guard);
 
-    Thread::spawn_kernel_thread(
     ThreadOptions::new(ap_idle_thread)
         .cpu_affinity(cpu_id.into())
-            .priority(Priority::new(PriorityRange::new(PriorityRange::MAX))),
-    );
+        .priority(Priority::new(PriorityRange::new(PriorityRange::MAX)))
+        .spawn();
 }
 
 fn init_thread() {
@@ -139,9 +134,10 @@ fn init_thread() {
     fs::lazy_init();
     ipc::init();
     // driver::pci::virtio::block::block_device_test();
-    let thread = Thread::spawn_kernel_thread(ThreadOptions::new(|| {
+    let thread = ThreadOptions::new(|| {
         println!("[kernel] Hello world from kernel!");
-    }));
+    })
+    .spawn();
     thread.join();
 
     print_banner();

kernel/src/net/iface/poll.rs

@@ -9,10 +9,7 @@ use ostd::timer::Jiffies;
 use super::{ext::IfaceEx, Iface, IFACES};
 use crate::{
     sched::priority::{Priority, PriorityRange},
-    thread::{
-        kernel_thread::{KernelThreadExt, ThreadOptions},
-        Thread,
-    },
+    thread::kernel_thread::ThreadOptions,
     WaitTimeout,
 };
 
@@ -70,6 +67,7 @@ fn spawn_background_poll_thread(iface: Arc<Iface>) {
     };
 
     // FIXME: remove the use of real-time priority.
-    let options = ThreadOptions::new(task_fn).priority(Priority::new(PriorityRange::new(0)));
-    Thread::spawn_kernel_thread(options);
+    ThreadOptions::new(task_fn)
+        .priority(Priority::new(PriorityRange::new(0)))
+        .spawn();
 }

kernel/src/process/signal/pause.rs

@@ -217,10 +217,7 @@ mod test {
     use ostd::prelude::*;
 
     use super::*;
-    use crate::thread::{
-        kernel_thread::{KernelThreadExt, ThreadOptions},
-        Thread,
-    };
+    use crate::thread::{kernel_thread::ThreadOptions, Thread};
 
     #[ktest]
     fn test_waiter_pause() {
@@ -230,12 +227,13 @@ mod test {
         let boolean = Arc::new(AtomicBool::new(false));
         let boolean_cloned = boolean.clone();
 
-        let thread = Thread::spawn_kernel_thread(ThreadOptions::new(move || {
+        let thread = ThreadOptions::new(move || {
             Thread::yield_now();
 
             boolean_cloned.store(true, Ordering::Relaxed);
             wait_queue_cloned.wake_all();
-        }));
+        })
+        .spawn();
 
         wait_queue
             .pause_until(|| boolean.load(Ordering::Relaxed).then_some(()))

kernel/src/process/sync/condvar.rs

@@ -52,20 +52,21 @@ impl<Guard> LockErr<Guard> {
 /// ```rust
 /// use alloc::sync::Arc;
 /// use ostd::sync::Mutex;
-/// use crate::{process::sync::Condvar, thread::{kernel_thread::KernelThreadExt, Thread}};
+/// use crate::{process::sync::Condvar, thread::kernel_thread::Thread};
 ///
 /// // Initializing a shared condition between threads
 /// let pair = Arc::new((Mutex::new(false), Condvar::new()));
 /// let pair2 = Arc::clone(&pair);
 ///
 /// // Spawning a new kernel thread to change a shared state and notify the Condvar
-/// Thread::spawn_kernel_thread(ThreadOptions::new(move || {
+/// ThreadOptions::new(move || {
 ///     let (lock, cvar) = &*pair2;
 ///     Thread::yield_now();
 ///     let mut started = lock.lock();
 ///     *started = true; // Modifying the shared state
 ///     cvar.notify_one(); // Notifying one waiting thread
-/// }));
+/// })
+/// .spawn();
 ///
 /// // Main thread waiting for the shared state to be set to true
 /// {
@@ -267,23 +268,21 @@ mod test {
     use ostd::{prelude::*, sync::Mutex};
 
     use super::*;
-    use crate::thread::{
-        kernel_thread::{KernelThreadExt, ThreadOptions},
-        Thread,
-    };
+    use crate::thread::{kernel_thread::ThreadOptions, Thread};
 
     #[ktest]
     fn test_condvar_wait() {
         let pair = Arc::new((Mutex::new(false), Condvar::new()));
         let pair2 = Arc::clone(&pair);
 
-        Thread::spawn_kernel_thread(ThreadOptions::new(move || {
+        ThreadOptions::new(move || {
             Thread::yield_now();
             let (lock, cvar) = &*pair2;
             let mut started = lock.lock();
             *started = true;
             cvar.notify_one();
-        }));
+        })
+        .spawn();
 
         {
             let (lock, cvar) = &*pair;
@@ -300,13 +299,14 @@ mod test {
         let pair = Arc::new((Mutex::new(false), Condvar::new()));
         let pair2 = Arc::clone(&pair);
 
-        Thread::spawn_kernel_thread(ThreadOptions::new(move || {
+        ThreadOptions::new(move || {
             Thread::yield_now();
             let (lock, cvar) = &*pair2;
             let mut started = lock.lock();
             *started = true;
             cvar.notify_one();
-        }));
+        })
+        .spawn();
 
         {
             let (lock, cvar) = &*pair;
@@ -325,13 +325,14 @@ mod test {
         let pair = Arc::new((Mutex::new(true), Condvar::new()));
         let pair2 = Arc::clone(&pair);
 
-        Thread::spawn_kernel_thread(ThreadOptions::new(move || {
+        ThreadOptions::new(move || {
             Thread::yield_now();
             let (lock, cvar) = &*pair2;
             let mut started = lock.lock();
             *started = false;
             cvar.notify_one();
-        }));
+        })
+        .spawn();
 
         {
             let (lock, cvar) = &*pair;
@@ -347,13 +348,14 @@ mod test {
         let pair = Arc::new((Mutex::new(true), Condvar::new()));
         let pair2 = Arc::clone(&pair);
 
-        Thread::spawn_kernel_thread(ThreadOptions::new(move || {
+        ThreadOptions::new(move || {
             Thread::yield_now();
             let (lock, cvar) = &*pair2;
             let mut started = lock.lock();
             *started = false;
             cvar.notify_one();
-        }));
+        })
+        .spawn();
 
         {
             let (lock, cvar) = &*pair;

kernel/src/thread/kernel_thread.rs

@@ -8,42 +8,47 @@ use ostd::{
 use super::{oops, status::ThreadStatus, Thread};
 use crate::{prelude::*, sched::priority::Priority};
 
-/// The inner data of a kernel thread
-pub struct KernelThread;
+/// The inner data of a kernel thread.
+struct KernelThread;
 
-pub trait KernelThreadExt {
-    /// Gets the kernel_thread structure
-    fn as_kernel_thread(&self) -> Option<&KernelThread>;
-    /// Creates a new kernel thread, and then run the thread.
-    fn spawn_kernel_thread(thread_options: ThreadOptions) -> Arc<Thread> {
-        let task = create_new_kernel_task(thread_options);
-        let thread = Thread::borrow_from_task(&task).clone();
-        thread.run();
-        thread
-    }
-    /// join a kernel thread, returns if the kernel thread exit
-    fn join(&self);
+/// Options to create or spawn a new kernel thread.
+pub struct ThreadOptions {
+    func: Option<Box<dyn Fn() + Send + Sync>>,
+    priority: Priority,
+    cpu_affinity: CpuSet,
 }
 
-impl KernelThreadExt for Thread {
-    fn as_kernel_thread(&self) -> Option<&KernelThread> {
-        self.data().downcast_ref::<KernelThread>()
-    }
-
-    fn join(&self) {
-        loop {
-            if self.is_exited() {
-                return;
-            } else {
-                Thread::yield_now();
-            }
-        }
+impl ThreadOptions {
+    /// Creates the thread options with the thread function.
+    pub fn new<F>(func: F) -> Self
+    where
+        F: Fn() + Send + Sync + 'static,
+    {
+        let cpu_affinity = CpuSet::new_full();
+        Self {
+            func: Some(Box::new(func)),
+            priority: Priority::default(),
+            cpu_affinity,
         }
     }
 
-/// Creates a new task of kernel thread, **NOT** run the thread.
-pub fn create_new_kernel_task(mut thread_options: ThreadOptions) -> Arc<Task> {
-    let task_fn = thread_options.take_func();
+    /// Sets the priority of the new thread.
+    pub fn priority(mut self, priority: Priority) -> Self {
+        self.priority = priority;
+        self
+    }
+
+    /// Sets the CPU affinity of the new thread.
+    pub fn cpu_affinity(mut self, cpu_affinity: CpuSet) -> Self {
+        self.cpu_affinity = cpu_affinity;
+        self
+    }
+}
+
+impl ThreadOptions {
+    /// Builds a new kernel thread without running it immediately.
+    pub fn build(mut self) -> Arc<Task> {
+        let task_fn = self.func.take().unwrap();
         let thread_fn = move || {
             let _ = oops::catch_panics_as_oops(task_fn);
             // Ensure that the thread exits.
@@ -54,8 +59,8 @@ pub fn create_new_kernel_task(mut thread_options: ThreadOptions) -> Arc<Task> {
             let thread = {
                 let kernel_thread = KernelThread;
                 let status = ThreadStatus::Init;
-            let priority = thread_options.priority;
-            let cpu_affinity = thread_options.cpu_affinity;
+                let priority = self.priority;
+                let cpu_affinity = self.cpu_affinity;
                 Arc::new(Thread::new(
                     weak_task.clone(),
                     kernel_thread,
@@ -69,45 +74,11 @@ pub fn create_new_kernel_task(mut thread_options: ThreadOptions) -> Arc<Task> {
         })
     }
 
-/// Options to create or spawn a new thread.
-pub struct ThreadOptions {
-    func: Option<Box<dyn Fn() + Send + Sync>>,
-    priority: Priority,
-    cpu_affinity: CpuSet,
-}
-
-impl ThreadOptions {
-    pub fn new<F>(func: F) -> Self
-    where
-        F: Fn() + Send + Sync + 'static,
-    {
-        let cpu_affinity = CpuSet::new_full();
-        Self {
-            func: Some(Box::new(func)),
-            priority: Priority::default(),
-            cpu_affinity,
-        }
-    }
-
-    pub fn func<F>(mut self, func: F) -> Self
-    where
-        F: Fn() + Send + Sync + 'static,
-    {
-        self.func = Some(Box::new(func));
-        self
-    }
-
-    fn take_func(&mut self) -> Box<dyn Fn() + Send + Sync> {
-        self.func.take().unwrap()
-    }
-
-    pub fn priority(mut self, priority: Priority) -> Self {
-        self.priority = priority;
-        self
-    }
-
-    pub fn cpu_affinity(mut self, cpu_affinity: CpuSet) -> Self {
-        self.cpu_affinity = cpu_affinity;
-        self
+    /// 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();
+        thread.run();
+        thread
     }
 }

kernel/src/thread/mod.rs

@@ -152,10 +152,22 @@ impl Thread {
         &self.cpu_affinity
     }
 
+    /// Yields the execution to another thread.
+    ///
+    /// This method will return once the current thread is scheduled again.
     pub fn yield_now() {
         Task::yield_now()
     }
 
+    /// Joins the execution of the thread.
+    ///
+    /// This method will return after the thread exits.
+    pub fn join(&self) {
+        while !self.is_exited() {
+            Self::yield_now();
+        }
+    }
+
     /// Returns the associated data.
     pub fn data(&self) -> &(dyn Send + Sync + Any) {
         &*self.data

kernel/src/thread/work_queue/worker.rs

@@ -11,7 +11,7 @@ use super::worker_pool::WorkerPool;
 use crate::{
     prelude::*,
     sched::priority::{Priority, PriorityRange},
-    thread::kernel_thread::{create_new_kernel_task, ThreadOptions},
+    thread::kernel_thread::ThreadOptions,
     Thread,
 };
 
@@ -56,11 +56,10 @@ impl Worker {
                 // FIXME: remove the use of real-time priority.
                 priority = Priority::new(PriorityRange::new(0));
             }
-            let bound_task = create_new_kernel_task(
-                ThreadOptions::new(task_fn)
+            let bound_task = ThreadOptions::new(task_fn)
                 .cpu_affinity(cpu_affinity)
-                    .priority(priority),
-            );
+                .priority(priority)
+                .build();
             Self {
                 worker_pool,
                 bound_task,

kernel/src/thread/work_queue/worker_pool.rs

@@ -17,7 +17,7 @@ use super::{simple_scheduler::SimpleScheduler, worker::Worker, WorkItem, WorkPri
 use crate::{
     prelude::*,
     sched::priority::{Priority, PriorityRange},
-    thread::kernel_thread::{create_new_kernel_task, ThreadOptions},
+    thread::kernel_thread::ThreadOptions,
     Thread,
 };
 
@@ -246,11 +246,10 @@ impl Monitor {
                 WorkPriority::High => Priority::new(PriorityRange::new(0)),
                 WorkPriority::Normal => Priority::default(),
             };
-            let bound_task = create_new_kernel_task(
-                ThreadOptions::new(task_fn)
+            let bound_task = ThreadOptions::new(task_fn)
                 .cpu_affinity(cpu_affinity)
-                    .priority(priority),
-            );
+                .priority(priority)
+                .build();
             Self {
                 worker_pool,
                 bound_task,

ostd/src/task/mod.rs

@@ -215,7 +215,7 @@ impl TaskOptions {
         Ok(new_task)
     }
 
-    /// Builds a new task and run it immediately.
+    /// Builds a new task and runs it immediately.
     pub fn spawn(self) -> Result<Arc<Task>> {
         let task = Arc::new(self.build()?);
         task.run();