ThreadOptions is not fully used while creating new kernel thread

[jellllly420]

Here is the aster-nix::thread::kernel_thread::ThreadOptions.

/// Options to create or spawn a new thread.
pub struct ThreadOptions {
    func: Option<Box<dyn Fn() + Send + Sync>>,
    priority: Priority,
    cpu_affinity: CpuSet,
}

It has fields representing priority and cpu affinity. But when we create new kernel thread in the code below,

fn new_kernel_thread(mut thread_options: ThreadOptions) -> Arc<Self> {
        let task_fn = thread_options.take_func();
        let thread_fn = move || {
            task_fn();
            let current_thread = current_thread!();
            // ensure the thread is exit
            current_thread.exit();
        };
        let tid = allocate_tid();
        let thread = Arc::new_cyclic(|thread_ref| {
            let weal_thread = thread_ref.clone();
            let task = TaskOptions::new(thread_fn)
                .data(weal_thread)
                .build()
                .unwrap();
            let status = ThreadStatus::Init;
            let kernel_thread = KernelThread;
            Thread::new(tid, task, kernel_thread, status)
        });
        thread_table::add_thread(thread.clone());
        thread
    }

we never use this two fields to construct TaskOptions, therefore the bound task is always of default configuration.

One problem caused by this issue is that all Workers in WORKERPOOL_HIGH_PRI are of normal priority instead of real-time priority, which is incorrect and can cause starvation in some specific cases.

[tatetian]

@jellllly420 Good job on spotting the bug. Could you try to fix it?