rust: thread: Add Thread wrapper

.github/workflows/ci.yaml

@@ -354,6 +354,10 @@ jobs:
           grep '] rust_sync: Value: 10$'                                     qemu-stdout.log
           grep '] rust_sync: Rust synchronisation primitives sample (exit)$' qemu-stdout.log
 
+      - run: |
+          grep '] rust_thread: Rust thread APIs sample (init)$' qemu-stdout.log
+          grep '] rust_thread: Rust thread APIs sample (exit)$' qemu-stdout.log
+
       - run: |
           grep '] rust_chrdev: Rust character device sample (init)$' qemu-stdout.log
           grep '] rust_chrdev: Rust character device sample (exit)$' qemu-stdout.log

.github/workflows/kernel-arm-debug.config

@@ -1774,6 +1774,7 @@ CONFIG_SAMPLE_RUST_MINIMAL=m
 CONFIG_SAMPLE_RUST_PRINT=m
 CONFIG_SAMPLE_RUST_MODULE_PARAMETERS=m
 CONFIG_SAMPLE_RUST_SYNC=m
+CONFIG_SAMPLE_RUST_THREAD=m
 CONFIG_SAMPLE_RUST_CHRDEV=m
 CONFIG_SAMPLE_RUST_MISCDEV=m
 CONFIG_SAMPLE_RUST_STACK_PROBING=m

.github/workflows/kernel-arm-release.config

@@ -1698,6 +1698,7 @@ CONFIG_SAMPLE_RUST_MINIMAL=m
 CONFIG_SAMPLE_RUST_PRINT=m
 CONFIG_SAMPLE_RUST_MODULE_PARAMETERS=m
 CONFIG_SAMPLE_RUST_SYNC=m
+CONFIG_SAMPLE_RUST_THREAD=m
 CONFIG_SAMPLE_RUST_CHRDEV=m
 CONFIG_SAMPLE_RUST_MISCDEV=m
 CONFIG_SAMPLE_RUST_STACK_PROBING=m

.github/workflows/kernel-arm64-debug.config

@@ -1426,6 +1426,7 @@ CONFIG_SAMPLE_RUST_MINIMAL=m
 CONFIG_SAMPLE_RUST_PRINT=m
 CONFIG_SAMPLE_RUST_MODULE_PARAMETERS=m
 CONFIG_SAMPLE_RUST_SYNC=m
+CONFIG_SAMPLE_RUST_THREAD=m
 CONFIG_SAMPLE_RUST_CHRDEV=m
 CONFIG_SAMPLE_RUST_MISCDEV=m
 CONFIG_SAMPLE_RUST_STACK_PROBING=m

.github/workflows/kernel-arm64-release.config

@@ -1344,6 +1344,7 @@ CONFIG_SAMPLE_RUST_MINIMAL=m
 CONFIG_SAMPLE_RUST_PRINT=m
 CONFIG_SAMPLE_RUST_MODULE_PARAMETERS=m
 CONFIG_SAMPLE_RUST_SYNC=m
+CONFIG_SAMPLE_RUST_THREAD=m
 CONFIG_SAMPLE_RUST_CHRDEV=m
 CONFIG_SAMPLE_RUST_MISCDEV=m
 CONFIG_SAMPLE_RUST_STACK_PROBING=m

.github/workflows/kernel-ppc64le-debug.config

@@ -1486,6 +1486,7 @@ CONFIG_SAMPLE_RUST_MINIMAL=m
 CONFIG_SAMPLE_RUST_PRINT=m
 CONFIG_SAMPLE_RUST_MODULE_PARAMETERS=m
 CONFIG_SAMPLE_RUST_SYNC=m
+CONFIG_SAMPLE_RUST_THREAD=m
 CONFIG_SAMPLE_RUST_CHRDEV=m
 CONFIG_SAMPLE_RUST_MISCDEV=m
 CONFIG_SAMPLE_RUST_STACK_PROBING=m

.github/workflows/kernel-ppc64le-release.config

@@ -1448,6 +1448,7 @@ CONFIG_SAMPLE_RUST_MINIMAL=m
 CONFIG_SAMPLE_RUST_PRINT=m
 CONFIG_SAMPLE_RUST_MODULE_PARAMETERS=m
 CONFIG_SAMPLE_RUST_SYNC=m
+CONFIG_SAMPLE_RUST_THREAD=m
 CONFIG_SAMPLE_RUST_CHRDEV=m
 CONFIG_SAMPLE_RUST_MISCDEV=m
 CONFIG_SAMPLE_RUST_STACK_PROBING=m

.github/workflows/kernel-riscv64-debug.config

@@ -1280,6 +1280,7 @@ CONFIG_SAMPLE_RUST_MINIMAL=m
 CONFIG_SAMPLE_RUST_PRINT=m
 CONFIG_SAMPLE_RUST_MODULE_PARAMETERS=m
 CONFIG_SAMPLE_RUST_SYNC=m
+CONFIG_SAMPLE_RUST_THREAD=m
 CONFIG_SAMPLE_RUST_CHRDEV=m
 CONFIG_SAMPLE_RUST_MISCDEV=m
 CONFIG_SAMPLE_RUST_STACK_PROBING=m

.github/workflows/kernel-riscv64-release.config

@@ -1196,6 +1196,7 @@ CONFIG_SAMPLE_RUST_MINIMAL=m
 CONFIG_SAMPLE_RUST_PRINT=m
 CONFIG_SAMPLE_RUST_MODULE_PARAMETERS=m
 CONFIG_SAMPLE_RUST_SYNC=m
+CONFIG_SAMPLE_RUST_THREAD=m
 CONFIG_SAMPLE_RUST_CHRDEV=m
 CONFIG_SAMPLE_RUST_MISCDEV=m
 CONFIG_SAMPLE_RUST_STACK_PROBING=m

.github/workflows/kernel-x86_64-debug.config

@@ -1438,6 +1438,7 @@ CONFIG_SAMPLE_RUST_MINIMAL=m
 CONFIG_SAMPLE_RUST_PRINT=m
 CONFIG_SAMPLE_RUST_MODULE_PARAMETERS=m
 CONFIG_SAMPLE_RUST_SYNC=m
+CONFIG_SAMPLE_RUST_THREAD=m
 CONFIG_SAMPLE_RUST_CHRDEV=m
 CONFIG_SAMPLE_RUST_MISCDEV=m
 CONFIG_SAMPLE_RUST_STACK_PROBING=m

.github/workflows/kernel-x86_64-release.config

@@ -1386,6 +1386,7 @@ CONFIG_SAMPLE_RUST_MINIMAL=m
 CONFIG_SAMPLE_RUST_PRINT=m
 CONFIG_SAMPLE_RUST_MODULE_PARAMETERS=m
 CONFIG_SAMPLE_RUST_SYNC=m
+CONFIG_SAMPLE_RUST_THREAD=m
 CONFIG_SAMPLE_RUST_CHRDEV=m
 CONFIG_SAMPLE_RUST_MISCDEV=m
 CONFIG_SAMPLE_RUST_STACK_PROBING=m

.github/workflows/qemu-init.sh

@@ -12,6 +12,9 @@ busybox  rmmod rust_module_parameters.ko
 busybox insmod rust_sync.ko
 busybox  rmmod rust_sync.ko
 
+busybox insmod rust_thread.ko
+busybox  rmmod rust_thread.ko
+
 busybox insmod rust_chrdev.ko
 busybox  rmmod rust_chrdev.ko
 

.github/workflows/qemu-initramfs.desc

@@ -9,6 +9,7 @@ file    /rust_minimal.ko            samples/rust/rust_minimal.ko            0755
 file    /rust_print.ko              samples/rust/rust_print.ko              0755 0 0
 file    /rust_module_parameters.ko  samples/rust/rust_module_parameters.ko  0755 0 0
 file    /rust_sync.ko               samples/rust/rust_sync.ko               0755 0 0
+file    /rust_thread.ko             samples/rust/rust_thread.ko             0755 0 0
 file    /rust_chrdev.ko             samples/rust/rust_chrdev.ko             0755 0 0
 file    /rust_miscdev.ko            samples/rust/rust_miscdev.ko            0755 0 0
 file    /rust_stack_probing.ko      samples/rust/rust_stack_probing.ko      0755 0 0

rust/kernel/bindings_helper.h

@@ -3,6 +3,7 @@
 #include <linux/cdev.h>
 #include <linux/errname.h>
 #include <linux/fs.h>
+#include <linux/kthread.h>
 #include <linux/module.h>
 #include <linux/random.h>
 #include <linux/slab.h>

rust/kernel/error.rs

@@ -490,8 +490,6 @@ macro_rules! from_kernel_result {
 ///     }
 /// }
 /// ```
-// TODO: remove `dead_code` marker once an in-kernel client is available.
-#[allow(dead_code)]
 pub(crate) fn from_kernel_err_ptr<T>(ptr: *mut T) -> Result<*mut T> {
     // CAST: casting a pointer to `*const c_types::c_void` is always valid.
     let const_ptr: *const c_types::c_void = ptr.cast();

rust/kernel/lib.rs

@@ -69,6 +69,7 @@ pub mod print;
 pub mod random;
 mod static_assert;
 pub mod sync;
+pub mod thread;
 
 #[cfg(any(CONFIG_SYSCTL, doc))]
 #[doc(cfg(CONFIG_SYSCTL))]

rust/kernel/task.rs

@@ -108,6 +108,16 @@ impl Task {
         // SAFETY: By the type invariant, we know that `self.ptr` is non-null and valid.
         unsafe { bindings::signal_pending(self.ptr) != 0 }
     }
+
+    /// Wakes up the task.
+    pub fn wake_up(&self) {
+        // SAFETY: By the type invariant, we know that `self.ptr` is non-null and valid.
+        // And `wake_up_process` is safe to be called for any valid task, even if the task is
+        // running.
+        unsafe {
+            bindings::wake_up_process(self.ptr);
+        }
+    }
 }
 
 impl PartialEq for Task {