fix _rt_scheduler_stack_check

git-svn-id: https://rt-thread.googlecode.com/svn/trunk@47 bbd45198-f89e-11dd-88c7-29a3b14d5316

src/scheduler.c

@@ -1,414 +1,417 @@
-/*
- * File      : scheduler.c
- * This file is part of RT-Thread RTOS
- * COPYRIGHT (C) 2006, RT-Thread Development Team
- *
- * The license and distribution terms for this file may be
- * found in the file LICENSE in this distribution or at
- * http://openlab.rt-thread.com/license/LICENSE
- *
- * Change Logs:
- * Date           Author       Notes
- * 2006-03-17     Bernard      the first version
- * 2006-04-28     Bernard      fix the scheduler algorthm
- * 2006-04-30     Bernard      add SCHEDULER_DEBUG
- * 2006-05-27     Bernard      fix the scheduler algorthm for same priority thread
- *                             schedule
- * 2006-06-04     Bernard      rewrite the scheduler algorithm
- * 2006-08-03     Bernard      add hook support
- * 2006-09-05     Bernard      add 32 priority level support
- * 2006-09-24     Bernard      add rt_system_scheduler_start function
- */
-
-#include <rtthread.h>
-#include <rthw.h>
-
-#include "kservice.h"
-
-/* #define SCHEDULER_DEBUG */
-
-static rt_int16_t rt_scheduler_lock_nest;
-extern rt_uint32_t rt_interrupt_nest;
-
-rt_list_t rt_thread_priority_table[RT_THREAD_PRIORITY_MAX];
-struct rt_thread* rt_current_thread;
-
-rt_uint8_t rt_current_priority;
-
-#if RT_THREAD_PRIORITY_MAX > 32
-/* maximun priority level, 256 */
-rt_uint32_t rt_thread_ready_priority_group;
-rt_uint8_t rt_thread_ready_table[32];
-#else
-/* maximun priority level, 32 */
-rt_uint32_t rt_thread_ready_priority_group;
-#endif
-
-#ifdef RT_USING_HEAP
-rt_list_t rt_thread_defunct;
-#endif
-
-const rt_uint8_t rt_lowest_bitmap[] =
-{
-	/* 00 */ 0, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
-	/* 10 */ 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
-	/* 20 */ 5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
-	/* 30 */ 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
-	/* 40 */ 6, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
-	/* 50 */ 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
-	/* 60 */ 5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
-	/* 70 */ 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
-	/* 80 */ 7, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
-	/* 90 */ 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
-	/* A0 */ 5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
-	/* B0 */ 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
-	/* C0 */ 6, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
-	/* D0 */ 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
-	/* E0 */ 5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
-	/* F0 */ 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0
-};
-
-#ifdef RT_USING_HOOK
-static void (*rt_scheduler_hook)(struct rt_thread* from, struct rt_thread* to);
-
-/**
- * @addtogroup Hook
- */
-/*@{*/
-
-/**
- * This function will set a hook function, which will be invoked when thread
- * switch happens.
- *
- * @param hook the hook function
- */
-void rt_scheduler_sethook(void (*hook)(struct rt_thread* from, struct rt_thread* to))
-{
-	rt_scheduler_hook = hook;
-}
-
-/*@}*/
-#endif
-
-#ifdef RT_USING_OVERFLOW_CHECK
-static void _rt_scheduler_stack_check(struct rt_thread* thread)
-{
-	RT_ASSERT(thread != RT_NULL);
-	
-	if ((rt_uint32_t)thread->sp <= (rt_uint32_t)thread->stack_addr)
-	{
-		rt_uint32_t level;
-		
-		rt_kprintf("thread:%s stack overflow\n", thread->name);
-		level = rt_hw_interrupt_disable();
-		while (level);
-	}
-	else if ((rt_uint32_t)thread->sp <= ((rt_uint32_t)thread->stack_addr + 32))
-	{
-		rt_kprintf("warning: %s stack is close to end of stack address.\n",
-			thread->name);
-	}
-}
-#endif
-
-/**
- * @ingroup SystemInit
- * This function will init the system scheduler
- *
- */
-void rt_system_scheduler_init(void)
-{
-	register rt_base_t offset;
-
-	rt_scheduler_lock_nest = 0;
-
-	for (offset = 0; offset < RT_THREAD_PRIORITY_MAX; offset ++)
-	{
-		rt_list_init(&rt_thread_priority_table[offset]);
-	}
-
-	rt_current_priority = RT_THREAD_PRIORITY_MAX - 1;
-	rt_current_thread	= RT_NULL;
-
-	/* init ready priority group */
-	rt_thread_ready_priority_group = 0;
-
-#if RT_THREAD_PRIORITY_MAX > 32
-	/* init ready table */
-	rt_memset(rt_thread_ready_table, 0, sizeof(rt_thread_ready_table));
-#endif
-
-#ifdef RT_USING_HEAP
-	/* init thread defunct */
-	rt_list_init(&rt_thread_defunct);
-#endif
-}
-
-/**
- * This function will startup scheduler. It will select one thread
- * with the highest priority level, then switch to it.
- */
-void rt_system_scheduler_start()
-{
-	register rt_uint8_t number;
-	register rt_uint8_t highest_ready_priority;
-
-	struct rt_thread *to_thread;
-
-	/* find out the highest priority task */
-	if (rt_thread_ready_priority_group & 0xff)
-	{
-		number = rt_lowest_bitmap[rt_thread_ready_priority_group & 0xff];
-	}
-	else if (rt_thread_ready_priority_group & 0xff00)
-	{
-		number = rt_lowest_bitmap[(rt_thread_ready_priority_group >> 8) & 0xff] + 8;
-	}
-	else if (rt_thread_ready_priority_group & 0xff0000)
-	{
-		number = rt_lowest_bitmap[(rt_thread_ready_priority_group >> 16) & 0xff] + 16;
-	}
-	else
-	{
-		number = rt_lowest_bitmap[(rt_thread_ready_priority_group >> 24) & 0xff] + 24;
-	}
-
-#if RT_THREAD_PRIORITY_MAX > 32
-	highest_ready_priority = (number << 3) + rt_lowest_bitmap[rt_thread_ready_table[number]];
-#else
-	highest_ready_priority = number;
-#endif
-
-	/* get switch to thread */
-	to_thread = rt_list_entry(rt_thread_priority_table[highest_ready_priority].next,
-		struct rt_thread, tlist);
-
-	rt_current_thread = to_thread;
-
-	/* switch to new thread */
-	rt_hw_context_switch_to((rt_uint32_t)&to_thread->sp);
-
-	/* never come back */
-}
-
-/**
- * @addtogroup Thread
- */
-/*@{*/
-
-/**
- * This function will perform one schedule. It will select one thread
- * with the highest priority level, then switch to it.
- */
-void rt_schedule()
-{
-	register rt_uint8_t number;
-	register rt_base_t level;
-	register rt_uint8_t highest_ready_priority;
-
-	struct rt_thread *to_thread;
-	struct rt_thread *from_thread;
-
-	/* disable interrupt */
-	level = rt_hw_interrupt_disable();
-
-	/* check the scheduler is enabled or not */
-	if(rt_scheduler_lock_nest == 0)
-	{
-		/* find out the highest priority task */
-		if (rt_thread_ready_priority_group & 0xff)
-		{
-			number = rt_lowest_bitmap[rt_thread_ready_priority_group & 0xff];
-		}
-		else if (rt_thread_ready_priority_group & 0xff00)
-		{
-			number = rt_lowest_bitmap[(rt_thread_ready_priority_group >> 8) & 0xff] + 8;
-		}
-		else if (rt_thread_ready_priority_group & 0xff0000)
-		{
-			number = rt_lowest_bitmap[(rt_thread_ready_priority_group >> 16) & 0xff] + 16;
-		}
-		else
-		{
-			number = rt_lowest_bitmap[(rt_thread_ready_priority_group >> 24) & 0xff] + 24;
-		}
-
-#if RT_THREAD_PRIORITY_MAX > 32
-		highest_ready_priority = (number << 3) + rt_lowest_bitmap[rt_thread_ready_table[number]];
-#else
-		highest_ready_priority = number;
-#endif
-		/* get switch to thread */
-		to_thread = rt_list_entry(rt_thread_priority_table[highest_ready_priority].next,
-			struct rt_thread, tlist);
-
-		/* if the destination thread is not the same as current thread */
-		if (to_thread != rt_current_thread)
-		{
-			rt_current_priority = highest_ready_priority;
-			from_thread = rt_current_thread;
-			rt_current_thread = to_thread;
-
-#ifdef RT_USING_HOOK
-			if (rt_scheduler_hook != RT_NULL) rt_scheduler_hook(from_thread, to_thread);
-#endif
-
-			/* switch to new thread */
-#ifdef SCHEDULER_DEBUG
-			rt_kprintf("[%d]switch to priority#%d thread:%s\n", rt_interrupt_nest,
-				highest_ready_priority, to_thread->name);
-#endif
-#ifdef RT_USING_OVERFLOW_CHECK
-			_rt_scheduler_stack_check(to_thread);
-#endif
-
-			if (rt_interrupt_nest == 0)
-			{
-				rt_hw_context_switch((rt_uint32_t)&from_thread->sp, (rt_uint32_t)&to_thread->sp);
-			}
-			else
-			{
-#ifdef SCHEDULER_DEBUG
-				rt_kprintf("switch in interrupt\n");
-#endif
-				rt_hw_context_switch_interrupt((rt_uint32_t)&from_thread->sp,
-					(rt_uint32_t)&to_thread->sp);
-			}
-		}
-	}
-
-	/* enable interrupt */
-	rt_hw_interrupt_enable(level);
-}
-
-/**
- * This function will insert a thread to system ready queue. The state of
- * thread will be set as READY and remove from suspend queue.
- *
- * @param thread the thread to be inserted
- * @note Please do not invoke this function in user application.
- */
-void rt_schedule_insert_thread(struct rt_thread* thread)
-{
-	register rt_base_t temp;
-
-	RT_ASSERT(thread != RT_NULL);
-
-	/* disable interrupt */
-	temp = rt_hw_interrupt_disable();
-
-	/* change stat */
-	thread->stat = RT_THREAD_READY;
-
-	/* insert thread to ready list */
-	rt_list_insert_before(&(rt_thread_priority_table[thread->current_priority]),
-		&(thread->tlist));
-
-	/* set priority mask */
-#ifdef SCHEDULER_DEBUG
-#if RT_THREAD_PRIORITY_MAX == 32
-	rt_kprintf("insert thread, the priority: %d\n", thread->current_priority);
-#else
-	rt_kprintf("insert thread, the priority: %d 0x%x %d\n", thread->number, thread->number_mask, thread->high_mask);
-#endif
-#endif
-
-#if RT_THREAD_PRIORITY_MAX > 32
-	rt_thread_ready_table[thread->number] |= thread->high_mask;
-#endif
-	rt_thread_ready_priority_group |= thread->number_mask;
-
-	/* enable interrupt */
-	rt_hw_interrupt_enable(temp);
-}
-
-/**
- * This function will remove a thread from system ready queue.
- *
- * @param thread the thread to be removed
- *
- * @note Please do not invoke this function in user application.
- */
-void rt_schedule_remove_thread(struct rt_thread* thread)
-{
-	register rt_base_t temp;
-
-	RT_ASSERT(thread != RT_NULL);
-
-	/* disable interrupt */
-	temp = rt_hw_interrupt_disable();
-
-#ifdef SCHEDULER_DEBUG
-#if RT_THREAD_PRIORITY_MAX == 32
-	rt_kprintf("remove thread, the priority: %d\n", thread->current_priority);
-#else
-	rt_kprintf("remove thread, the priority: %d 0x%x %d\n", thread->number,
-		thread->number_mask, thread->high_mask);
-#endif
-#endif
-
-	/* remove thread from ready list */
-	rt_list_remove(&(thread->tlist));
-	if (rt_list_isempty(&(rt_thread_priority_table[thread->current_priority])))
-	{
-#if RT_THREAD_PRIORITY_MAX > 32
-		rt_thread_ready_table[thread->number] &= ~thread->high_mask;
-		if (rt_thread_ready_table[thread->number] == 0)
-		{
-			rt_thread_ready_priority_group &= ~thread->number_mask;
-		}
-#else
-		rt_thread_ready_priority_group &= ~thread->number_mask;
-#endif
-	}
-
-	/* enable interrupt */
-	rt_hw_interrupt_enable(temp);
-}
-
-/**
- * This function will lock the thread scheduler.
- */
-void rt_enter_critical()
-{
-	register rt_base_t level;
-
-	/* disable interrupt */
-	level = rt_hw_interrupt_disable();
-
-	if (rt_scheduler_lock_nest < 255u)
-		rt_scheduler_lock_nest++;
-
-	/* enable interrupt */
-	rt_hw_interrupt_enable(level);
-}
-
-/**
- * This function will unlock the thread scheduler.
- */
-void rt_exit_critical()
-{
-	register rt_base_t level;
-
-	/* disable interrupt */
-	level = rt_hw_interrupt_disable();
-
-	rt_scheduler_lock_nest --;
-
-	if (rt_scheduler_lock_nest <= 0)
-	{
-		rt_scheduler_lock_nest = 0;
-		/* enable interrupt */
-		rt_hw_interrupt_enable(level);
-
-		rt_schedule();
-	}
-	else
-	{
-		/* enable interrupt */
-		rt_hw_interrupt_enable(level);
-	}
-}
-
-/*@}*/
-
+/*
+ * File      : scheduler.c
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2006, RT-Thread Development Team
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://openlab.rt-thread.com/license/LICENSE
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2006-03-17     Bernard      the first version
+ * 2006-04-28     Bernard      fix the scheduler algorthm
+ * 2006-04-30     Bernard      add SCHEDULER_DEBUG
+ * 2006-05-27     Bernard      fix the scheduler algorthm for same priority thread
+ *                             schedule
+ * 2006-06-04     Bernard      rewrite the scheduler algorithm
+ * 2006-08-03     Bernard      add hook support
+ * 2006-09-05     Bernard      add 32 priority level support
+ * 2006-09-24     Bernard      add rt_system_scheduler_start function
+ * 2009-09-16     Bernard      fix _rt_scheduler_stack_check
+ */
+
+#include <rtthread.h>
+#include <rthw.h>
+
+#include "kservice.h"
+
+/* #define SCHEDULER_DEBUG */
+
+static rt_int16_t rt_scheduler_lock_nest;
+extern rt_uint32_t rt_interrupt_nest;
+
+rt_list_t rt_thread_priority_table[RT_THREAD_PRIORITY_MAX];
+struct rt_thread* rt_current_thread;
+
+rt_uint8_t rt_current_priority;
+
+#if RT_THREAD_PRIORITY_MAX > 32
+/* maximun priority level, 256 */
+rt_uint32_t rt_thread_ready_priority_group;
+rt_uint8_t rt_thread_ready_table[32];
+#else
+/* maximun priority level, 32 */
+rt_uint32_t rt_thread_ready_priority_group;
+#endif
+
+#ifdef RT_USING_HEAP
+rt_list_t rt_thread_defunct;
+#endif
+
+const rt_uint8_t rt_lowest_bitmap[] =
+{
+    /* 00 */ 0, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
+    /* 10 */ 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
+    /* 20 */ 5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
+    /* 30 */ 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
+    /* 40 */ 6, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
+    /* 50 */ 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
+    /* 60 */ 5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
+    /* 70 */ 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
+    /* 80 */ 7, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
+    /* 90 */ 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
+    /* A0 */ 5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
+    /* B0 */ 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
+    /* C0 */ 6, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
+    /* D0 */ 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
+    /* E0 */ 5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
+    /* F0 */ 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0
+};
+
+#ifdef RT_USING_HOOK
+static void (*rt_scheduler_hook)(struct rt_thread* from, struct rt_thread* to);
+
+/**
+ * @addtogroup Hook
+ */
+/*@{*/
+
+/**
+ * This function will set a hook function, which will be invoked when thread
+ * switch happens.
+ *
+ * @param hook the hook function
+ */
+void rt_scheduler_sethook(void (*hook)(struct rt_thread* from, struct rt_thread* to))
+{
+    rt_scheduler_hook = hook;
+}
+
+/*@}*/
+#endif
+
+#ifdef RT_USING_OVERFLOW_CHECK
+static void _rt_scheduler_stack_check(struct rt_thread* thread)
+{
+    RT_ASSERT(thread != RT_NULL);
+
+    if ( (rt_uint32_t)thread->sp <= (rt_uint32_t)thread->stack_addr ||
+            (rt_uint32_t)thread->sp >
+            (rt_uint32_t)thread->stack_addr + (rt_uint32_t)thread->stack_size )
+    {
+        rt_uint32_t level;
+
+        rt_kprintf("thread:%s stack overflow\n", thread->name);
+        level = rt_hw_interrupt_disable();
+        while (level);
+    }
+    else if ((rt_uint32_t)thread->sp <= ((rt_uint32_t)thread->stack_addr + 32))
+    {
+        rt_kprintf("warning: %s stack is close to end of stack address.\n",
+                   thread->name);
+    }
+}
+#endif
+
+/**
+ * @ingroup SystemInit
+ * This function will init the system scheduler
+ *
+ */
+void rt_system_scheduler_init(void)
+{
+    register rt_base_t offset;
+
+    rt_scheduler_lock_nest = 0;
+
+    for (offset = 0; offset < RT_THREAD_PRIORITY_MAX; offset ++)
+    {
+        rt_list_init(&rt_thread_priority_table[offset]);
+    }
+
+    rt_current_priority = RT_THREAD_PRIORITY_MAX - 1;
+    rt_current_thread	= RT_NULL;
+
+    /* init ready priority group */
+    rt_thread_ready_priority_group = 0;
+
+#if RT_THREAD_PRIORITY_MAX > 32
+    /* init ready table */
+    rt_memset(rt_thread_ready_table, 0, sizeof(rt_thread_ready_table));
+#endif
+
+#ifdef RT_USING_HEAP
+    /* init thread defunct */
+    rt_list_init(&rt_thread_defunct);
+#endif
+}
+
+/**
+ * This function will startup scheduler. It will select one thread
+ * with the highest priority level, then switch to it.
+ */
+void rt_system_scheduler_start()
+{
+    register rt_uint8_t number;
+    register rt_uint8_t highest_ready_priority;
+
+    struct rt_thread *to_thread;
+
+    /* find out the highest priority task */
+    if (rt_thread_ready_priority_group & 0xff)
+    {
+        number = rt_lowest_bitmap[rt_thread_ready_priority_group & 0xff];
+    }
+    else if (rt_thread_ready_priority_group & 0xff00)
+    {
+        number = rt_lowest_bitmap[(rt_thread_ready_priority_group >> 8) & 0xff] + 8;
+    }
+    else if (rt_thread_ready_priority_group & 0xff0000)
+    {
+        number = rt_lowest_bitmap[(rt_thread_ready_priority_group >> 16) & 0xff] + 16;
+    }
+    else
+    {
+        number = rt_lowest_bitmap[(rt_thread_ready_priority_group >> 24) & 0xff] + 24;
+    }
+
+#if RT_THREAD_PRIORITY_MAX > 32
+    highest_ready_priority = (number << 3) + rt_lowest_bitmap[rt_thread_ready_table[number]];
+#else
+    highest_ready_priority = number;
+#endif
+
+    /* get switch to thread */
+    to_thread = rt_list_entry(rt_thread_priority_table[highest_ready_priority].next,
+                              struct rt_thread, tlist);
+
+    rt_current_thread = to_thread;
+
+    /* switch to new thread */
+    rt_hw_context_switch_to((rt_uint32_t)&to_thread->sp);
+
+    /* never come back */
+}
+
+/**
+ * @addtogroup Thread
+ */
+/*@{*/
+
+/**
+ * This function will perform one schedule. It will select one thread
+ * with the highest priority level, then switch to it.
+ */
+void rt_schedule()
+{
+    register rt_uint8_t number;
+    register rt_base_t level;
+    register rt_uint8_t highest_ready_priority;
+
+    struct rt_thread *to_thread;
+    struct rt_thread *from_thread;
+
+    /* disable interrupt */
+    level = rt_hw_interrupt_disable();
+
+    /* check the scheduler is enabled or not */
+    if (rt_scheduler_lock_nest == 0)
+    {
+        /* find out the highest priority task */
+        if (rt_thread_ready_priority_group & 0xff)
+        {
+            number = rt_lowest_bitmap[rt_thread_ready_priority_group & 0xff];
+        }
+        else if (rt_thread_ready_priority_group & 0xff00)
+        {
+            number = rt_lowest_bitmap[(rt_thread_ready_priority_group >> 8) & 0xff] + 8;
+        }
+        else if (rt_thread_ready_priority_group & 0xff0000)
+        {
+            number = rt_lowest_bitmap[(rt_thread_ready_priority_group >> 16) & 0xff] + 16;
+        }
+        else
+        {
+            number = rt_lowest_bitmap[(rt_thread_ready_priority_group >> 24) & 0xff] + 24;
+        }
+
+#if RT_THREAD_PRIORITY_MAX > 32
+        highest_ready_priority = (number << 3) + rt_lowest_bitmap[rt_thread_ready_table[number]];
+#else
+        highest_ready_priority = number;
+#endif
+        /* get switch to thread */
+        to_thread = rt_list_entry(rt_thread_priority_table[highest_ready_priority].next,
+                                  struct rt_thread, tlist);
+
+        /* if the destination thread is not the same as current thread */
+        if (to_thread != rt_current_thread)
+        {
+            rt_current_priority = highest_ready_priority;
+            from_thread = rt_current_thread;
+            rt_current_thread = to_thread;
+
+#ifdef RT_USING_HOOK
+            if (rt_scheduler_hook != RT_NULL) rt_scheduler_hook(from_thread, to_thread);
+#endif
+
+            /* switch to new thread */
+#ifdef SCHEDULER_DEBUG
+            rt_kprintf("[%d]switch to priority#%d thread:%s\n", rt_interrupt_nest,
+                       highest_ready_priority, to_thread->name);
+#endif
+#ifdef RT_USING_OVERFLOW_CHECK
+            _rt_scheduler_stack_check(to_thread);
+#endif
+
+            if (rt_interrupt_nest == 0)
+            {
+                rt_hw_context_switch((rt_uint32_t)&from_thread->sp, (rt_uint32_t)&to_thread->sp);
+            }
+            else
+            {
+#ifdef SCHEDULER_DEBUG
+                rt_kprintf("switch in interrupt\n");
+#endif
+                rt_hw_context_switch_interrupt((rt_uint32_t)&from_thread->sp,
+                                               (rt_uint32_t)&to_thread->sp);
+            }
+        }
+    }
+
+    /* enable interrupt */
+    rt_hw_interrupt_enable(level);
+}
+
+/**
+ * This function will insert a thread to system ready queue. The state of
+ * thread will be set as READY and remove from suspend queue.
+ *
+ * @param thread the thread to be inserted
+ * @note Please do not invoke this function in user application.
+ */
+void rt_schedule_insert_thread(struct rt_thread* thread)
+{
+    register rt_base_t temp;
+
+    RT_ASSERT(thread != RT_NULL);
+
+    /* disable interrupt */
+    temp = rt_hw_interrupt_disable();
+
+    /* change stat */
+    thread->stat = RT_THREAD_READY;
+
+    /* insert thread to ready list */
+    rt_list_insert_before(&(rt_thread_priority_table[thread->current_priority]),
+                          &(thread->tlist));
+
+    /* set priority mask */
+#ifdef SCHEDULER_DEBUG
+#if RT_THREAD_PRIORITY_MAX == 32
+    rt_kprintf("insert thread, the priority: %d\n", thread->current_priority);
+#else
+    rt_kprintf("insert thread, the priority: %d 0x%x %d\n", thread->number, thread->number_mask, thread->high_mask);
+#endif
+#endif
+
+#if RT_THREAD_PRIORITY_MAX > 32
+    rt_thread_ready_table[thread->number] |= thread->high_mask;
+#endif
+    rt_thread_ready_priority_group |= thread->number_mask;
+
+    /* enable interrupt */
+    rt_hw_interrupt_enable(temp);
+}
+
+/**
+ * This function will remove a thread from system ready queue.
+ *
+ * @param thread the thread to be removed
+ *
+ * @note Please do not invoke this function in user application.
+ */
+void rt_schedule_remove_thread(struct rt_thread* thread)
+{
+    register rt_base_t temp;
+
+    RT_ASSERT(thread != RT_NULL);
+
+    /* disable interrupt */
+    temp = rt_hw_interrupt_disable();
+
+#ifdef SCHEDULER_DEBUG
+#if RT_THREAD_PRIORITY_MAX == 32
+    rt_kprintf("remove thread, the priority: %d\n", thread->current_priority);
+#else
+    rt_kprintf("remove thread, the priority: %d 0x%x %d\n", thread->number,
+               thread->number_mask, thread->high_mask);
+#endif
+#endif
+
+    /* remove thread from ready list */
+    rt_list_remove(&(thread->tlist));
+    if (rt_list_isempty(&(rt_thread_priority_table[thread->current_priority])))
+    {
+#if RT_THREAD_PRIORITY_MAX > 32
+        rt_thread_ready_table[thread->number] &= ~thread->high_mask;
+        if (rt_thread_ready_table[thread->number] == 0)
+        {
+            rt_thread_ready_priority_group &= ~thread->number_mask;
+        }
+#else
+        rt_thread_ready_priority_group &= ~thread->number_mask;
+#endif
+    }
+
+    /* enable interrupt */
+    rt_hw_interrupt_enable(temp);
+}
+
+/**
+ * This function will lock the thread scheduler.
+ */
+void rt_enter_critical()
+{
+    register rt_base_t level;
+
+    /* disable interrupt */
+    level = rt_hw_interrupt_disable();
+
+    if (rt_scheduler_lock_nest < 255u)
+        rt_scheduler_lock_nest++;
+
+    /* enable interrupt */
+    rt_hw_interrupt_enable(level);
+}
+
+/**
+ * This function will unlock the thread scheduler.
+ */
+void rt_exit_critical()
+{
+    register rt_base_t level;
+
+    /* disable interrupt */
+    level = rt_hw_interrupt_disable();
+
+    rt_scheduler_lock_nest --;
+
+    if (rt_scheduler_lock_nest <= 0)
+    {
+        rt_scheduler_lock_nest = 0;
+        /* enable interrupt */
+        rt_hw_interrupt_enable(level);
+
+        rt_schedule();
+    }
+    else
+    {
+        /* enable interrupt */
+        rt_hw_interrupt_enable(level);
+    }
+}
+
+/*@}*/
+