STM32应用linux内核链表

STM32应用linux内核链表

在此之前,已经对Linux内核链表已经移植过一次。不过是针对Windows平台,下面是链接:https://blog.csdn.net/qq_36883460/article/details/105330799

链表是非常重要的数据结构,针对不同的情况使用不同数据结构,去解决不同的问题。它的优点:动态删除数据单元,不需要移动元素,存储空间可以不连续(与数组相比)。

1、开发环境

使用的开发板:正点原子开发板战舰V3
单片机型号:STM32F103ZET6

开发软件平台:Keil 5

下载linux内核版本:4.19.144 大小:98.64MB

内核代码查看使用软件:Source Insight 4.0

2、移植

由于Keil 5编译从/linux-4.19.144/include/list.h直接复制过来代码有些问题需要修改,要从这些定义头文件里面复制相关代码出来,并加以修改。。

list.h文件里面定义了几个头文件,清除这几个文件的依赖,如下文件:

#include
#include
#include
#include
#include

【1】在这个工程文件里面,按照红色框里面添加 --gnu 在这里提前写这个,大量减少了报错STM32应用linux内核链表_第1张图片
【2】先在types.h,存放了结构体拷贝下来,放到移植的头文件。

struct list_head {
    struct list_head* next, * prev;
};

【3】在Keil5平台上,new会成为关键字,new修改成newStruct,保留typeof()代码不改。

【4】删除了预编译定义 #ifdef CONFIG_DEBUG_LIST与 #else 里面相关代码,只保留了 #else 与 #endif 里面代码。
【5】bool 类型使用可能会出现报错,我查找了uVision Help相关文件,使用这个类型要定义头文件

//bool类型会报错,定义这个头文件才行,我的移植添加了这个
#include 

【6】未定义NULL、LIST_POISON1、LIST_POISON2 ,找了相关的代码发现这样定义比较好一点

#define NULL 0

#define LIST_POISON1  NULL
#define LIST_POISON2  NULL

【7】inline属于C++关键字,这里注释掉这个关键字,一般Ctrl+F换出窗口选择Replace进行替换

inline 替换成 /* inline */

【8】在linux内核文件找到相关定义并修改如下,

#define offsetof(TYPE, MEMBER)	((size_t)&((TYPE *)0)->MEMBER)

#define container_of(ptr, type, member) \
	(type *)( (char *)(ptr) - offsetof(type,member))

其中**container_of()**是通过 成员变量地址 经过计算偏移后 找到 父地址,然后就可以通过指针访问,找到结构体里面其他的变量成员,这个比较美妙了。换句话说,将这个list_head添加到自己的代码里面就能用了。

3、移植后的代码

//代码移植日期:2020/4/8
//代码移植者:须须草

#ifndef _LINUX_LIST_H
#define _LINUX_LIST_H

//bool类型定义,引用的头文件
#include 

//结构体文件路径/linux/types.h定义
struct list_head {
    struct list_head* next, * prev;
};

struct hlist_head {
    struct hlist_node* first;
};

struct hlist_node {
    struct hlist_node* next, ** pprev;
};

// 文件路径/tool/virtio/linux/compiler.h
//这里报错添加--gnu -O1 -g -W
#define WRITE_ONCE(var, val)  (*((volatile typeof(var)*)(&(var))) = (val))

#define READ_ONCE(var) (*((volatile typeof(var) *)(&(var))))

//手动定义NULL
#define NULL 0

//去除C++编译器预指令
/*#ifdef __cplusplus*/

#define LIST_POISON1  NULL
#define LIST_POISON2  NULL

/*#endif */

/*
 * Simple doubly linked list implementation.
 *
 * Some of the internal functions ("__xxx") are useful when
 * manipulating whole lists rather than single entries, as
 * sometimes we already know the next/prev entries and we can
 * generate better code by using them directly rather than
 * using the generic single-entry routines.
 */

#define LIST_HEAD_INIT(name) { &(name), &(name) }

#define LIST_HEAD(name) \
	struct list_head name = LIST_HEAD_INIT(name)

static /*  inline */void INIT_LIST_HEAD(struct list_head* list)
{
    WRITE_ONCE(list->next, list);
    list->prev = list;
}


static /*  inline */bool __list_add_valid(struct list_head* newStruct,
    struct list_head* prev,
    struct list_head* next)
{
    return true;
}
static /*  inline */bool __list_del_entry_valid(struct list_head* entry)
{
    return true;
}

/*
 * Insert a new entry between two known consecutive entries.
 *
 * This is only for internal list manipulation where we know
 * the prev/next entries already!
 */
static /*  inline */void __list_add(struct list_head* newStruct,
    struct list_head* prev,
    struct list_head* next)
{
    if (!__list_add_valid(newStruct, prev, next))
        return;

    next->prev = newStruct;
    newStruct->next = next;
    newStruct->prev = prev;
    WRITE_ONCE(prev->next, newStruct);
}

/**
 * list_add - add a newStruct entry
 * @newStruct: new entry to be added
 * @head: list head to add it after
 *
 * Insert a new entry after the specified head.
 * This is good for implementing stacks.
 */
static /*  inline */void list_add(struct list_head* newStruct, struct list_head* head)
{
    __list_add(newStruct, head, head->next);
}


/**
 * list_add_tail - add a newStruct entry
 * @newStruct: new entry to be added
 * @head: list head to add it before
 *
 * Insert a new entry before the specified head.
 * This is useful for implementing queues.
 */
static /*  inline */void list_add_tail(struct list_head* newStruct, struct list_head* head)
{
    __list_add(newStruct, head->prev, head);
}

/*
 * Delete a list entry by making the prev/next entries
 * point to each other.
 *
 * This is only for internal list manipulation where we know
 * the prev/next entries already!
 */
static /*  inline */void __list_del(struct list_head* prev, struct list_head* next)
{
    next->prev = prev;
    WRITE_ONCE(prev->next, next);
}

/**
 * list_del - deletes entry from list.
 * @entry: the element to delete from the list.
 * Note: list_empty() on entry does not return true after this, the entry is
 * in an undefined state.
 */
static /*  inline */void __list_del_entry(struct list_head* entry)
{
    if (!__list_del_entry_valid(entry))
        return;

    __list_del(entry->prev, entry->next);
}

static /*  inline */void list_del(struct list_head* entry)
{
    __list_del_entry(entry);
    entry->next = LIST_POISON1;
    entry->prev = LIST_POISON2;
}

/**
 * list_replace - replace old entry by new one
 * @old : the element to be replaced
 * @newStruct : the new element to insert
 *
 * If @old was empty, it will be overwritten.
 */
static /*  inline */void list_replace(struct list_head* old,
    struct list_head* newStruct)
{
    newStruct->next = old->next;
    newStruct->next->prev = newStruct;
    newStruct->prev = old->prev;
    newStruct->prev->next = newStruct;
}

static /*  inline */void list_replace_init(struct list_head* old,
    struct list_head* newStruct)
{
    list_replace(old, newStruct);
    INIT_LIST_HEAD(old);
}

/**
 * list_del_init - deletes entry from list and reinitialize it.
 * @entry: the element to delete from the list.
 */
static /*  inline */void list_del_init(struct list_head* entry)
{
    __list_del_entry(entry);
    INIT_LIST_HEAD(entry);
}

/**
 * list_move - delete from one list and add as another's head
 * @list: the entry to move
 * @head: the head that will precede our entry
 */
static /*  inline */void list_move(struct list_head* list, struct list_head* head)
{
    __list_del_entry(list);
    list_add(list, head);
}

/**
 * list_move_tail - delete from one list and add as another's tail
 * @list: the entry to move
 * @head: the head that will follow our entry
 */
static /*  inline */void list_move_tail(struct list_head* list,
    struct list_head* head)
{
    __list_del_entry(list);
    list_add_tail(list, head);
}

/**
 * list_is_last - tests whether @list is the last entry in list @head
 * @list: the entry to test
 * @head: the head of the list
 */
static /*  inline */int list_is_last(const struct list_head* list,
    const struct list_head* head)
{
    return list->next == head;
}

/**
 * list_empty - tests whether a list is empty
 * @head: the list to test.
 */
static /*  inline */int list_empty(const struct list_head* head)
{
    return READ_ONCE(head->next) == head;
}

/**
 * list_empty_careful - tests whether a list is empty and not being modified
 * @head: the list to test
 *
 * Description:
 * tests whether a list is empty _and_ checks that no other CPU might be
 * in the process of modifying either member (next or prev)
 *
 * NOTE: using list_empty_careful() without synchronization
 * can only be safe if the only activity that can happen
 * to the list entry is list_del_init(). Eg. it cannot be used
 * if another CPU could re-list_add() it.
 */
static /*  inline */int list_empty_careful(const struct list_head* head)
{
    struct list_head* next = head->next;
    return (next == head) && (next == head->prev);
}

/**
 * list_rotate_left - rotate the list to the left
 * @head: the head of the list
 */
static /*  inline */void list_rotate_left(struct list_head* head)
{
    struct list_head* first;

    if (!list_empty(head)) {
        first = head->next;
        list_move_tail(first, head);
    }
}

/**
 * list_is_singular - tests whether a list has just one entry.
 * @head: the list to test.
 */
static /*  inline */int list_is_singular(const struct list_head* head)
{
    return !list_empty(head) && (head->next == head->prev);
}

static /*  inline */void __list_cut_position(struct list_head* list,
    struct list_head* head, struct list_head* entry)
{
    struct list_head* new_first = entry->next;
    list->next = head->next;
    list->next->prev = list;
    list->prev = entry;
    entry->next = list;
    head->next = new_first;
    new_first->prev = head;
}

/**
 * list_cut_position - cut a list into two
 * @list: a new list to add all removed entries
 * @head: a list with entries
 * @entry: an entry within head, could be the head itself
 *	and if so we won't cut the list
 *
 * This helper moves the initial part of @head, up to and
 * including @entry, from @head to @list. You should
 * pass on @entry an element you know is on @head. @list
 * should be an empty list or a list you do not care about
 * losing its data.
 *
 */
static /*  inline */void list_cut_position(struct list_head* list,
    struct list_head* head, struct list_head* entry)
{
    if (list_empty(head))
        return;
    if (list_is_singular(head) &&
        (head->next != entry && head != entry))
        return;
    if (entry == head)
        INIT_LIST_HEAD(list);
    else
        __list_cut_position(list, head, entry);
}

static /*  inline */void __list_splice(const struct list_head* list,
    struct list_head* prev,
    struct list_head* next)
{
    struct list_head* first = list->next;
    struct list_head* last = list->prev;

    first->prev = prev;
    prev->next = first;

    last->next = next;
    next->prev = last;
}

/**
 * list_splice - join two lists, this is designed for stacks
 * @list: the new list to add.
 * @head: the place to add it in the first list.
 */
static /*  inline */void list_splice(const struct list_head* list,
    struct list_head* head)
{
    if (!list_empty(list))
        __list_splice(list, head, head->next);
}

/**
 * list_splice_tail - join two lists, each list being a queue
 * @list: the new list to add.
 * @head: the place to add it in the first list.
 */
static /*  inline */void list_splice_tail(struct list_head* list,
    struct list_head* head)
{
    if (!list_empty(list))
        __list_splice(list, head->prev, head);
}

/**
 * list_splice_init - join two lists and reinitialise the emptied list.
 * @list: the new list to add.
 * @head: the place to add it in the first list.
 *
 * The list at @list is reinitialised
 */
static /*  inline */void list_splice_init(struct list_head* list,
    struct list_head* head)
{
    if (!list_empty(list)) {
        __list_splice(list, head, head->next);
        INIT_LIST_HEAD(list);
    }
}

/**
 * list_splice_tail_init - join two lists and reinitialise the emptied list
 * @list: the new list to add.
 * @head: the place to add it in the first list.
 *
 * Each of the lists is a queue.
 * The list at @list is reinitialised
 */
static /*  inline */void list_splice_tail_init(struct list_head* list,
    struct list_head* head)
{
    if (!list_empty(list)) {
        __list_splice(list, head->prev, head);
        INIT_LIST_HEAD(list);
    }
}

//ÓÉÓÚûÓÐoffsetofºê¶¨Ò壬Õâ¸öÎÒÐèÒªÖØÐÂÌí¼Ó¡£¡£¡£
#define offsetof(TYPE, MEMBER)	((size_t)&((TYPE *)0)->MEMBER)

#define container_of(ptr, type, member) (type *)((char *) (ptr) - offsetof(type,member))

/**
 * list_entry - get the struct for this entry
 * @ptr:	the &struct list_head pointer.
 * @type:	the type of the struct this is embedded in.
 * @member:	the name of the list_head within the struct.
 */
#define list_entry(ptr, type, member) \
	container_of(ptr, type, member)

 /**
  * list_first_entry - get the first element from a list
  * @ptr:	the list head to take the element from.
  * @type:	the type of the struct this is embedded in.
  * @member:	the name of the list_head within the struct.
  *
  * Note, that list is expected to be not empty.
  */
#define list_first_entry(ptr, type, member) \
	list_entry((ptr)->next, type, member)

  /**
   * list_last_entry - get the last element from a list
   * @ptr:	the list head to take the element from.
   * @type:	the type of the struct this is embedded in.
   * @member:	the name of the list_head within the struct.
   *
   * Note, that list is expected to be not empty.
   */
#define list_last_entry(ptr, type, member) \
	list_entry((ptr)->prev, type, member)

   /**
    * list_first_entry_or_null - get the first element from a list
    * @ptr:	the list head to take the element from.
    * @type:	the type of the struct this is embedded in.
    * @member:	the name of the list_head within the struct.
    *
    * Note that if the list is empty, it returns NULL.
    */
#define list_first_entry_or_null(ptr, type, member) ({ \
	struct list_head *head__ = (ptr); \
	struct list_head *pos__ = READ_ONCE(head__->next); \
	pos__ != head__ ? list_entry(pos__, type, member) : NULL; \
})

    /**
     * list_next_entry - get the next element in list
     * @pos:	the type * to cursor
     * @member:	the name of the list_head within the struct.
     */
#define list_next_entry(pos, member) \
	list_entry((pos)->member.next, typeof(*(pos)), member)

     /**
      * list_prev_entry - get the prev element in list
      * @pos:	the type * to cursor
      * @member:	the name of the list_head within the struct.
      */
#define list_prev_entry(pos, member) \
	list_entry((pos)->member.prev, typeof(*(pos)), member)

      /**
       * list_for_each	-	iterate over a list
       * @pos:	the &struct list_head to use as a loop cursor.
       * @head:	the head for your list.
       */
#define list_for_each(pos, head) \
	for (pos = (head)->next; pos != (head); pos = pos->next)

       /**
        * list_for_each_prev	-	iterate over a list backwards
        * @pos:	the &struct list_head to use as a loop cursor.
        * @head:	the head for your list.
        */
#define list_for_each_prev(pos, head) \
	for (pos = (head)->prev; pos != (head); pos = pos->prev)

        /**
         * list_for_each_safe - iterate over a list safe against removal of list entry
         * @pos:	the &struct list_head to use as a loop cursor.
         * @n:		another &struct list_head to use as temporary storage
         * @head:	the head for your list.
         */
#define list_for_each_safe(pos, n, head) \
	for (pos = (head)->next, n = pos->next; pos != (head); \
		pos = n, n = pos->next)

         /**
          * list_for_each_prev_safe - iterate over a list backwards safe against removal of list entry
          * @pos:	the &struct list_head to use as a loop cursor.
          * @n:		another &struct list_head to use as temporary storage
          * @head:	the head for your list.
          */
#define list_for_each_prev_safe(pos, n, head) \
	for (pos = (head)->prev, n = pos->prev; \
	     pos != (head); \
	     pos = n, n = pos->prev)

          /**
           * list_for_each_entry	-	iterate over list of given type
           * @pos:	the type * to use as a loop cursor.
           * @head:	the head for your list.
           * @member:	the name of the list_head within the struct.
           */
#define list_for_each_entry(pos, head, member)				\
	for (pos = list_first_entry(head, typeof(*pos), member);	\
	     &pos->member != (head);					\
	     pos = list_next_entry(pos, member))

           /**
            * list_for_each_entry_reverse - iterate backwards over list of given type.
            * @pos:	the type * to use as a loop cursor.
            * @head:	the head for your list.
            * @member:	the name of the list_head within the struct.
            */
#define list_for_each_entry_reverse(pos, head, member)			\
	for (pos = list_last_entry(head, typeof(*pos), member);		\
	     &pos->member != (head); 					\
	     pos = list_prev_entry(pos, member))

            /**
             * list_prepare_entry - prepare a pos entry for use in list_for_each_entry_continue()
             * @pos:	the type * to use as a start point
             * @head:	the head of the list
             * @member:	the name of the list_head within the struct.
             *
             * Prepares a pos entry for use as a start point in list_for_each_entry_continue().
             */
#define list_prepare_entry(pos, head, member) \
	((pos) ? : list_entry(head, typeof(*pos), member))

             /**
              * list_for_each_entry_continue - continue iteration over list of given type
              * @pos:	the type * to use as a loop cursor.
              * @head:	the head for your list.
              * @member:	the name of the list_head within the struct.
              *
              * Continue to iterate over list of given type, continuing after
              * the current position.
              */
#define list_for_each_entry_continue(pos, head, member) 		\
	for (pos = list_next_entry(pos, member);			\
	     &pos->member != (head);					\
	     pos = list_next_entry(pos, member))

              /**
               * list_for_each_entry_continue_reverse - iterate backwards from the given point
               * @pos:	the type * to use as a loop cursor.
               * @head:	the head for your list.
               * @member:	the name of the list_head within the struct.
               *
               * Start to iterate over list of given type backwards, continuing after
               * the current position.
               */
#define list_for_each_entry_continue_reverse(pos, head, member)		\
	for (pos = list_prev_entry(pos, member);			\
	     &pos->member != (head);					\
	     pos = list_prev_entry(pos, member))

               /**
                * list_for_each_entry_from - iterate over list of given type from the current point
                * @pos:	the type * to use as a loop cursor.
                * @head:	the head for your list.
                * @member:	the name of the list_head within the struct.
                *
                * Iterate over list of given type, continuing from current position.
                */
#define list_for_each_entry_from(pos, head, member) 			\
	for (; &pos->member != (head);					\
	     pos = list_next_entry(pos, member))

                /**
                 * list_for_each_entry_from_reverse - iterate backwards over list of given type
                 *                                    from the current point
                 * @pos:	the type * to use as a loop cursor.
                 * @head:	the head for your list.
                 * @member:	the name of the list_head within the struct.
                 *
                 * Iterate backwards over list of given type, continuing from current position.
                 */
#define list_for_each_entry_from_reverse(pos, head, member)		\
	for (; &pos->member != (head);					\
	     pos = list_prev_entry(pos, member))

                 /**
                  * list_for_each_entry_safe - iterate over list of given type safe against removal of list entry
                  * @pos:	the type * to use as a loop cursor.
                  * @n:		another type * to use as temporary storage
                  * @head:	the head for your list.
                  * @member:	the name of the list_head within the struct.
                  */
#define list_for_each_entry_safe(pos, n, head, member)			\
	for (pos = list_first_entry(head, typeof(*pos), member),	\
		n = list_next_entry(pos, member);			\
	     &pos->member != (head); 					\
	     pos = n, n = list_next_entry(n, member))

                  /**
                   * list_for_each_entry_safe_continue - continue list iteration safe against removal
                   * @pos:	the type * to use as a loop cursor.
                   * @n:		another type * to use as temporary storage
                   * @head:	the head for your list.
                   * @member:	the name of the list_head within the struct.
                   *
                   * Iterate over list of given type, continuing after current point,
                   * safe against removal of list entry.
                   */
#define list_for_each_entry_safe_continue(pos, n, head, member) 		\
	for (pos = list_next_entry(pos, member), 				\
		n = list_next_entry(pos, member);				\
	     &pos->member != (head);						\
	     pos = n, n = list_next_entry(n, member))

                   /**
                    * list_for_each_entry_safe_from - iterate over list from current point safe against removal
                    * @pos:	the type * to use as a loop cursor.
                    * @n:		another type * to use as temporary storage
                    * @head:	the head for your list.
                    * @member:	the name of the list_head within the struct.
                    *
                    * Iterate over list of given type from current point, safe against
                    * removal of list entry.
                    */
#define list_for_each_entry_safe_from(pos, n, head, member) 			\
	for (n = list_next_entry(pos, member);					\
	     &pos->member != (head);						\
	     pos = n, n = list_next_entry(n, member))

                    /**
                     * list_for_each_entry_safe_reverse - iterate backwards over list safe against removal
                     * @pos:	the type * to use as a loop cursor.
                     * @n:		another type * to use as temporary storage
                     * @head:	the head for your list.
                     * @member:	the name of the list_head within the struct.
                     *
                     * Iterate backwards over list of given type, safe against removal
                     * of list entry.
                     */
#define list_for_each_entry_safe_reverse(pos, n, head, member)		\
	for (pos = list_last_entry(head, typeof(*pos), member),		\
		n = list_prev_entry(pos, member);			\
	     &pos->member != (head); 					\
	     pos = n, n = list_prev_entry(n, member))

                     /**
                      * list_safe_reset_next - reset a stale list_for_each_entry_safe loop
                      * @pos:	the loop cursor used in the list_for_each_entry_safe loop
                      * @n:		temporary storage used in list_for_each_entry_safe
                      * @member:	the name of the list_head within the struct.
                      *
                      * list_safe_reset_next is not safe to use in general if the list may be
                      * modified concurrently (eg. the lock is dropped in the loop body). An
                      * exception to this is if the cursor element (pos) is pinned in the list,
                      * and list_safe_reset_next is called after re-taking the lock and before
                      * completing the current iteration of the loop body.
                      */
#define list_safe_reset_next(pos, n, member)				\
	n = list_next_entry(pos, member)

                      /*
                       * Double linked lists with a single pointer list head.
                       * Mostly useful for hash tables where the two pointer list head is
                       * too wasteful.
                       * You lose the ability to access the tail in O(1).
                       */

#define HLIST_HEAD_INIT { .first = NULL }
#define HLIST_HEAD(name) struct hlist_head name = {  .first = NULL }
#define INIT_HLIST_HEAD(ptr) ((ptr)->first = NULL)
static /*  inline */void INIT_HLIST_NODE(struct hlist_node* h)
{
    h->next = NULL;
    h->pprev = NULL;
}

static /*  inline */int hlist_unhashed(const struct hlist_node* h)
{
    return !h->pprev;
}

static /*  inline */int hlist_empty(const struct hlist_head* h)
{
    return !READ_ONCE(h->first);
}

static /*  inline */void __hlist_del(struct hlist_node* n)
{
    struct hlist_node* next = n->next;
    struct hlist_node** pprev = n->pprev;

    WRITE_ONCE(*pprev, next);
    if (next)
        next->pprev = pprev;
}

static /*  inline */void hlist_del(struct hlist_node* n)
{
    __hlist_del(n);
    n->next = LIST_POISON1;
    n->pprev = LIST_POISON2;
}

static /*  inline */void hlist_del_init(struct hlist_node* n)
{
    if (!hlist_unhashed(n)) {
        __hlist_del(n);
        INIT_HLIST_NODE(n);
    }
}

static /*  inline */void hlist_add_head(struct hlist_node* n, struct hlist_head* h)
{
    struct hlist_node* first = h->first;
    n->next = first;
    if (first)
        first->pprev = &n->next;
    WRITE_ONCE(h->first, n);
    n->pprev = &h->first;
}

/* next must be != NULL */
static /*  inline */void hlist_add_before(struct hlist_node* n,
    struct hlist_node* next)
{
    n->pprev = next->pprev;
    n->next = next;
    next->pprev = &n->next;
    WRITE_ONCE(*(n->pprev), n);
}

static /*  inline */void hlist_add_behind(struct hlist_node* n,
    struct hlist_node* prev)
{
    n->next = prev->next;
    WRITE_ONCE(prev->next, n);
    n->pprev = &prev->next;

    if (n->next)
        n->next->pprev = &n->next;
}

/* after that we'll appear to be on some hlist and hlist_del will work */
static /*  inline */void hlist_add_fake(struct hlist_node* n)
{
    n->pprev = &n->next;
}

static /*  inline */bool hlist_fake(struct hlist_node* h)
{
    return h->pprev == &h->next;
}

/*
 * Check whether the node is the only node of the head without
 * accessing head:
 */
static /*  inline */bool hlist_is_singular_node(struct hlist_node* n, struct hlist_head* h)
{
    return !n->next && n->pprev == &h->first;
}

/*
 * Move a list from one list head to another. Fixup the pprev
 * reference of the first entry if it exists.
 */
static /*  inline */void hlist_move_list(struct hlist_head* old,
    struct hlist_head* newStruct)
{
    newStruct->first = old->first;
    if (newStruct->first)
        newStruct->first->pprev = &newStruct->first;
    old->first = NULL;
}

#define hlist_entry(ptr, type, member) container_of(ptr,type,member)

#define hlist_for_each(pos, head) \
	for (pos = (head)->first; pos ; pos = pos->next)

#define hlist_for_each_safe(pos, n, head) \
	for (pos = (head)->first; pos && ({ n = pos->next; 1; }); \
	     pos = n)

#define hlist_entry_safe(ptr, type, member) \
	({ typeof(ptr) ____ptr = (ptr); \
	   ____ptr ? hlist_entry(____ptr, type, member) : NULL; \
	})

/**
 * hlist_for_each_entry	- iterate over list of given type
 * @pos:	the type * to use as a loop cursor.
 * @head:	the head for your list.
 * @member:	the name of the hlist_node within the struct.
 */
#define hlist_for_each_entry(pos, head, member)				\
	for (pos = hlist_entry_safe((head)->first, typeof(*(pos)), member);\
	     pos;							\
	     pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member))

 /**
  * hlist_for_each_entry_continue - iterate over a hlist continuing after current point
  * @pos:	the type * to use as a loop cursor.
  * @member:	the name of the hlist_node within the struct.
  */
#define hlist_for_each_entry_continue(pos, member)			\
	for (pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member);\
	     pos;							\
	     pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member))

  /**
   * hlist_for_each_entry_from - iterate over a hlist continuing from current point
   * @pos:	the type * to use as a loop cursor.
   * @member:	the name of the hlist_node within the struct.
   */
#define hlist_for_each_entry_from(pos, member)				\
	for (; pos;							\
	     pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member))

   /**
    * hlist_for_each_entry_safe - iterate over list of given type safe against removal of list entry
    * @pos:	the type * to use as a loop cursor.
    * @n:		another &struct hlist_node to use as temporary storage
    * @head:	the head for your list.
    * @member:	the name of the hlist_node within the struct.
    */
#define hlist_for_each_entry_safe(pos, n, head, member) 		\
	for (pos = hlist_entry_safe((head)->first, typeof(*pos), member);\
	     pos && ({ n = pos->member.next; 1; });			\
	     pos = hlist_entry_safe(n, typeof(*pos), member))

#endif

5、主函数应用代码

#include "sys.h"
#include "usart.h"		
#include "delay.h"	 	 
#include "list.h"

struct student{

	char name[60];
	int id;
	struct list_head list;
};

int main(void)
{							

	struct student *q;
	struct student *p;

	struct student A = { "张三" ,13, LIST_HEAD_INIT(A.list) };
	struct student B = { "小红" ,22, LIST_HEAD_INIT(B.list) };
	struct student C = { "李四" ,34, LIST_HEAD_INIT(C.list) };
	
	list_add_tail(&B.list, &A.list);//B成员添加到A列队尾部
	list_add_tail(&C.list, &A.list);//C成员添加到A列队尾部
	
	Stm32_Clock_Init(9);	//8MHz晶振,8*9=72Mhz系统时钟
	uart_init(72,115200); 	//72MHz系统时钟,波特率115200
	delay_init(72);	   	 	//72MHz系统时钟

 	while(1)
	{
		
		q = container_of(&A.list, struct student , list);
		
		p = container_of(q->list.next, struct student , list);
		printf("---------------------------------");
		printf("name:  %d ",p->id); 
		printf("name:  %s ",p->name);
		printf("---------------------------------");
		
		p = container_of(q->list.next->next, struct student, list);
		printf("---------------------------------");
		printf("name:  %d ",p->id);
		printf("name:  %s ",p->name);
		printf("---------------------------------");
		
		p = container_of(q->list.next->next->next, struct student, list);
		printf("---------------------------------");
		printf("id:  %d ",p->id);
		printf("name:  %s ",p->name);
		printf("---------------------------------");
		delay_ms(2000); //ÑÓʱ2Ãë
	}		 
}

程序下载烧录,通过串口助手观察;
STM32应用linux内核链表_第2张图片
这个结果说明代码移植成功,而且编译后占用空间不大。

总结:利用linux内核链表移植到STM32非常便利,而且链表在数据结构中栈重要地位。

更新中。。。

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