[PATCH] [RSDL 1/6] lists: add list splice tail

[PATCH] [RSDL 1/6] lists: add list splice tail

[Con Kolivas]

Add a list_splice_tail variant of list_splice.

Patch-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Con Kolivas <kernel@kolivas.org>

---
 include/linux/list.h |   42 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)

Index: linux-2.6.20-rsdl/include/linux/list.h
===================================================================
--- linux-2.6.20-rsdl.orig/include/linux/list.h	2007-03-04 17:30:25.000000000 +1100
+++ linux-2.6.20-rsdl/include/linux/list.h	2007-03-04 17:30:30.000000000 +1100
@@ -332,6 +332,20 @@ static inline void __list_splice(struct 
 	at->prev = last;
 }
 
+static inline void __list_splice_tail(struct list_head *list,
+				      struct list_head *head)
+{
+	struct list_head *first = list->next;
+	struct list_head *last = list->prev;
+	struct list_head *at = head->prev;
+
+	first->prev = at;
+	at->next = first;
+
+	last->next = head;
+	head->prev = last;
+}
+
 /**
  * list_splice - join two lists
  * @list: the new list to add.
@@ -344,6 +358,18 @@ static inline void list_splice(struct li
 }
 
 /**
+ * list_splice_tail - join two lists at one's tail
+ * @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_tail(list, 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.
@@ -360,6 +386,22 @@ static inline void list_splice_init(stru
 }
 
 /**
+ * list_splice_init - join two lists at one's tail and reinitialise emptied
+ * @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_tail_init(struct list_head *list,
+					 struct list_head *head)
+{
+	if (!list_empty(list)) {
+		__list_splice_tail(list, head);
+		INIT_LIST_HEAD(list);
+	}
+}
+
+/**
  * list_entry - get the struct for this entry
  * @ptr:	the &struct list_head pointer.
  * @type:	the type of the struct this is embedded in.

-- 
-ck

Re: [PATCH] [RSDL 1/6] lists: add list splice tail

[Balbir Singh]

Con Kolivas wrote:
> Add a list_splice_tail variant of list_splice.
> 
> Patch-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
> Signed-off-by: Con Kolivas <kernel@kolivas.org>
> 

Acked-by: Balbir Singh <balbir@in.ibm.com>

I had the same exact patch in my memcontrol at
http://lkml.org/lkml/2007/2/24/68 (see the last
two functions).


-- 
	Warm Regards,
	Balbir Singh
	Linux Technology Center
	IBM, ISTL

Re: [PATCH] [RSDL 1/6] lists: add list splice tail

[Gerald Britton]

On Sun, Mar 04, 2007 at 06:02:13PM +1100, Con Kolivas wrote:
> Add a list_splice_tail variant of list_splice.
> 
> Patch-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
> Signed-off-by: Con Kolivas <kernel@kolivas.org>
...
> @@ -360,6 +386,22 @@ static inline void list_splice_init(stru
>  }
>  
>  /**
> + * list_splice_init - join two lists at one's tail and reinitialise emptied

You should update the comment to match the function.

				-- Gerald

> + * @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_tail_init(struct list_head *list,
> +					 struct list_head *head)

Re: [PATCH] [RSDL 1/6] lists: add list splice tail

[Con Kolivas]

On Monday 05 March 2007 04:33, Gerald Britton wrote:
> On Sun, Mar 04, 2007 at 06:02:13PM +1100, Con Kolivas wrote:
> > Add a list_splice_tail variant of list_splice.
> >
> > Patch-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
> > Signed-off-by: Con Kolivas <kernel@kolivas.org>
>
> ...
>
> > @@ -360,6 +386,22 @@ static inline void list_splice_init(stru
> >  }
> >
> >  /**
> > + * list_splice_init - join two lists at one's tail and reinitialise
> > emptied
>
> You should update the comment to match the function.

Doh! Thanks. I'll fix it in the split out patches I have on my web site for 
now.

-- 
-ck