net: Add new interfaces for SKB list light-weight init and splicing. (67fed459) · Commits · e / devices / android_kernel_samsung_universal8895

include/linux/skbuff.h

+94 −2

Original line number	Diff line number	Diff line
		@@ -660,6 +660,22 @@ static inline __u32 skb_queue_len(const struct sk_buff_head *list_)
		return list_->qlen;
		}

		/**
		* __skb_queue_head_init - initialize non-spinlock portions of sk_buff_head
		* @list: queue to initialize
		*
		* This initializes only the list and queue length aspects of
		* an sk_buff_head object. This allows to initialize the list
		* aspects of an sk_buff_head without reinitializing things like
		* the spinlock. It can also be used for on-stack sk_buff_head
		* objects where the spinlock is known to not be used.
		*/
		static inline void __skb_queue_head_init(struct sk_buff_head *list)
		{
		list->prev = list->next = (struct sk_buff *)list;
		list->qlen = 0;
		}

		/*
		* This function creates a split out lock class for each invocation;
		* this is needed for now since a whole lot of users of the skb-queue
		@@ -671,8 +687,7 @@ static inline __u32 skb_queue_len(const struct sk_buff_head *list_)
		static inline void skb_queue_head_init(struct sk_buff_head *list)
		{
		spin_lock_init(&list->lock);
		list->prev = list->next = (struct sk_buff *)list;
		list->qlen = 0;
		__skb_queue_head_init(list);
		}

		static inline void skb_queue_head_init_class(struct sk_buff_head *list,
		@@ -699,6 +714,83 @@ static inline void __skb_insert(struct sk_buff *newsk,
		list->qlen++;
		}

		static inline void __skb_queue_splice(const struct sk_buff_head *list,
		struct sk_buff *prev,
		struct sk_buff *next)
		{
		struct sk_buff *first = list->next;
		struct sk_buff *last = list->prev;

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

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

		/**
		* skb_queue_splice - join two skb 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 skb_queue_splice(const struct sk_buff_head *list,
		struct sk_buff_head *head)
		{
		if (!skb_queue_empty(list)) {
		__skb_queue_splice(list, (struct sk_buff *) head, head->next);
		head->qlen = list->qlen;
		}
		}

		/**
		* skb_queue_splice - join two skb 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 skb_queue_splice_init(struct sk_buff_head *list,
		struct sk_buff_head *head)
		{
		if (!skb_queue_empty(list)) {
		__skb_queue_splice(list, (struct sk_buff *) head, head->next);
		head->qlen = list->qlen;
		__skb_queue_head_init(list);
		}
		}

		/**
		* skb_queue_splice_tail - join two skb 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 skb_queue_splice_tail(const struct sk_buff_head *list,
		struct sk_buff_head *head)
		{
		if (!skb_queue_empty(list)) {
		__skb_queue_splice(list, head->prev, (struct sk_buff *) head);
		head->qlen = list->qlen;
		}
		}

		/**
		* skb_queue_splice_tail - join two skb 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 skb_queue_splice_tail_init(struct sk_buff_head *list,
		struct sk_buff_head *head)
		{
		if (!skb_queue_empty(list)) {
		__skb_queue_splice(list, head->prev, (struct sk_buff *) head);
		head->qlen = list->qlen;
		__skb_queue_head_init(list);
		}
		}

		/**
		* __skb_queue_after - queue a buffer at the list head
		* @list: list to use