Make Pauser work in raw tasks

kernel/aster-nix/src/prelude.rs

@@ -30,11 +30,20 @@ macro_rules! current {
     };
 }
 
-/// return current thread
+/// Returns the current thread.
+///
+/// # Panics
+///
+/// This macro will panic if the current task is not associated with a thread.
+///
+/// Except for unit tests, all tasks should be associated with threads. To write code that can be
+/// called directly in unit tests, consider using [`Thread::current`] instead.
+///
+/// [`Thread::current`]: crate::thread::Thread::current
 #[macro_export]
 macro_rules! current_thread {
     () => {
-        $crate::thread::Thread::current()
+        $crate::thread::Thread::current().expect("the current task is not associated with a thread")
     };
 }
 

kernel/aster-nix/src/process/process/mod.rs

@@ -641,7 +641,7 @@ impl Process {
 }
 
 pub fn current() -> Arc<Process> {
-    let current_thread = Thread::current();
+    let current_thread = current_thread!();
     if let Some(posix_thread) = current_thread.as_posix_thread() {
         posix_thread.process()
     } else {

kernel/aster-nix/src/process/process/timer_manager.rs

@@ -18,14 +18,12 @@ use ostd::{
 
 use super::Process;
 use crate::{
+    prelude::*,
     process::{
         posix_thread::PosixThreadExt,
         signal::{constants::SIGALRM, signals::kernel::KernelSignal},
     },
-    thread::{
-        work_queue::{submit_work_item, work_item::WorkItem},
-        Thread,
-    },
+    thread::work_queue::{submit_work_item, work_item::WorkItem},
     time::{
         clocks::{ProfClock, RealTimeClock},
         Timer, TimerManager,
@@ -38,7 +36,7 @@ use crate::{
 /// invoke the callbacks of expired timers which are based on the updated
 /// CPU clock.
 fn update_cpu_time() {
-    let current_thread = Thread::current();
+    let current_thread = current_thread!();
     if let Some(posix_thread) = current_thread.as_posix_thread() {
         let process = posix_thread.process();
         let timer_manager = process.timer_manager();

kernel/aster-nix/src/process/signal/pauser.rs

@@ -123,9 +123,9 @@ impl Pauser {
     where
         F: FnMut() -> Option<R>,
     {
-        let current_thread = current_thread!();
+        let current_thread = Thread::current();
         let sig_queue_waiter =
-            SigObserverRegistrar::new(&current_thread, self.sig_mask, self.clone());
+            SigObserverRegistrar::new(current_thread.as_ref(), self.sig_mask, self.clone());
 
         let cond = || {
             if let Some(res) = cond() {
@@ -174,8 +174,12 @@ enum SigObserverRegistrar<'a> {
 }
 
 impl<'a> SigObserverRegistrar<'a> {
-    fn new(current_thread: &'a Arc<Thread>, sig_mask: SigMask, pauser: Arc<Pauser>) -> Self {
-        let Some(thread) = current_thread.as_posix_thread() else {
+    fn new(
+        current_thread: Option<&'a Arc<Thread>>,
+        sig_mask: SigMask,
+        pauser: Arc<Pauser>,
+    ) -> Self {
+        let Some(thread) = current_thread.and_then(|thread| thread.as_posix_thread()) else {
             return Self::KernelThread;
         };
 
@@ -281,19 +285,17 @@ mod test {
         let boolean = Arc::new(AtomicBool::new(false));
         let boolean_cloned = boolean.clone();
 
-        let thread1 = Thread::spawn_kernel_thread(ThreadOptions::new(move || {
-            pauser
-                .pause_until(|| boolean.load(Ordering::Relaxed).then_some(()))
-                .unwrap();
-        }));
-
-        let thread2 = Thread::spawn_kernel_thread(ThreadOptions::new(move || {
+        let thread = Thread::spawn_kernel_thread(ThreadOptions::new(move || {
             Thread::yield_now();
+
             boolean_cloned.store(true, Ordering::Relaxed);
             pauser_cloned.resume_all();
         }));
 
-        thread1.join();
-        thread2.join();
+        pauser
+            .pause_until(|| boolean.load(Ordering::Relaxed).then_some(()))
+            .unwrap();
+
+        thread.join();
     }
 }

kernel/aster-nix/src/syscall/clock_gettime.rs

@@ -9,7 +9,7 @@ use super::SyscallReturn;
 use crate::{
     prelude::*,
     process::{posix_thread::PosixThreadExt, process_table},
-    thread::{thread_table, Thread},
+    thread::thread_table,
     time::{
         clockid_t,
         clocks::{
@@ -121,7 +121,7 @@ pub fn read_clock(clockid: clockid_t) -> Result<Duration> {
                 Ok(process.prof_clock().read_time())
             }
             ClockId::CLOCK_THREAD_CPUTIME_ID => {
-                let thread = Thread::current();
+                let thread = current_thread!();
                 Ok(thread.as_posix_thread().unwrap().prof_clock().read_time())
             }
         }

kernel/aster-nix/src/syscall/timer_create.rs

@@ -20,7 +20,6 @@ use crate::{
     thread::{
         thread_table,
         work_queue::{submit_work_item, work_item::WorkItem},
-        Thread,
     },
     time::{
         clockid_t,
@@ -113,7 +112,7 @@ pub fn sys_timer_create(
         match clock_id {
             ClockId::CLOCK_PROCESS_CPUTIME_ID => process_timer_manager.create_prof_timer(func),
             ClockId::CLOCK_THREAD_CPUTIME_ID => {
-                let current_thread = Thread::current();
+                let current_thread = current_thread!();
                 current_thread
                     .as_posix_thread()
                     .unwrap()

kernel/aster-nix/src/thread/mod.rs

@@ -50,15 +50,16 @@ impl Thread {
         }
     }
 
-    pub fn current() -> Arc<Self> {
-        let task = Task::current();
-        let thread = task
+    /// Returns the current thread, or `None` if the current task is not associated with a thread.
+    ///
+    /// Except for unit tests, all tasks should be associated with threads. This method is useful
+    /// when writing code that can be called directly by unit tests. If this isn't the case,
+    /// consider using [`current_thread!`] instead.
+    pub fn current() -> Option<Arc<Self>> {
+        Task::current()
             .data()
-            .downcast_ref::<Weak<Thread>>()
-            .expect("[Internal Error] task data should points to weak<thread>");
-        thread
+            .downcast_ref::<Weak<Thread>>()?
             .upgrade()
-            .expect("[Internal Error] current thread cannot be None")
     }
 
     pub(in crate::thread) fn task(&self) -> &Arc<Task> {