修改CFSqueue从Vec变成红黑树 (#229)

使用了由tickbh编写的rbtree： https://github.com/tickbh/rbtree-rs/blob/master/src/lib.rs

Co-authored-by: tickbh <tickdream125@hotmail.com>

kernel/src/arch/x86_64/asm/current.rs

@@ -6,6 +6,7 @@ use core::{arch::asm, sync::atomic::compiler_fence};
 #[inline]
 pub fn current_pcb() -> &'static mut process_control_block {
     let ret: Option<&mut process_control_block>;
+
     unsafe {
         let mut tmp: u64 = !(32767u64);
         compiler_fence(core::sync::atomic::Ordering::SeqCst);

kernel/src/arch/x86_64/include/asm/current.h

@@ -14,6 +14,7 @@ struct process_control_block *get_current_pcb()
 						 : "=r"(current)
 						 : "0"(~32767UL));
 	barrier();
+	
 	return current;
 };
 #define current_pcb get_current_pcb()