kernel: Add a convenience wake_up() function

kernel/src/arch/x86_64/CPU.cpp

@@ -149,7 +149,7 @@ extern "C" void arch_interrupt_entry(Registers* regs)
     {
         u8 scancode = IO::inb(0x60);
         scancode_queue.try_push(scancode);
-        g_io_thread->state = ThreadState::Runnable;
+        g_io_thread->wake_up();
         pic_eoi(regs);
     }
     else if (regs->isr == 66) // System call

kernel/src/main.cpp

@@ -69,7 +69,7 @@ Result<void> init()
     // Disable console logging before transferring control to userspace.
     setup_log(log_debug_enabled(), log_serial_enabled(), false);
 
-    init_thread->state = ThreadState::Runnable;
+    init_thread->wake_up();
 
     kernel_exit();
 }

kernel/src/sys/exit.cpp

@@ -19,7 +19,7 @@ Result<u64> sys_exit(Registers*, SyscallArgs args)
         if (child == -1 || child == (pid_t)current->id)
         {
             parent->child_being_waited_for = (pid_t)current->id;
-            parent->state = ThreadState::Runnable;
+            parent->wake_up();
         }
     }
 

kernel/src/thread/Scheduler.cpp

@@ -66,7 +66,7 @@ namespace Scheduler
 
     void signal_reap_thread()
     {
-        if (g_reap) g_reap->state = ThreadState::Runnable;
+        if (g_reap) g_reap->wake_up();
     }
 
     Result<Thread*> new_kernel_thread_impl(Thread* thread, const char* name)
@@ -268,7 +268,7 @@ namespace Scheduler
         {
             if (thread->state == ThreadState::Sleeping)
             {
-                if (--thread->sleep_ticks_left == 0) thread->state = ThreadState::Runnable;
+                if (--thread->sleep_ticks_left == 0) thread->wake_up();
             }
         }
 

kernel/src/thread/Thread.h

@@ -100,6 +100,11 @@ struct Thread : public LinkedListNode<Thread>
         return state == ThreadState::Idle;
     }
 
+    void wake_up()
+    {
+        state = ThreadState::Runnable;
+    }
+
     void init_regs_kernel();
     void init_regs_user();