[Devel] Re: [PATCH] Introduce a handy list_first_entry macro

[Randy Dunlap]

On Tue, 17 Apr 2007 15:18:56 +0400 Pavel Emelianov wrote:

> There are many places in the kernel where the construction like
> 
>    foo = list_entry(head->next, struct foo_struct, list);
> 
> are used. 
> The code might look more descriptive and neat if using the macro
> 
>    list_first_entry(head, type, member) \
>              list_entry((head)->next, type, member)
> 
> Here is the macro itself and the examples of its usage in the
> generic code. If it will turn out to be useful, I can prepare
> the set of patches to inject in into arch-specific code, drivers,
> networking, etc.
> 
> Signed-off-by: Pavel Emelianov <xemul at openvz.org>
> Signed-off-by: Kirill Korotaev <dev at openvz.org>
> 
> ---
> diff --git a/include/linux/list.h b/include/linux/list.h
> index fd59659..71318fc 100644
> --- a/include/linux/list.h
> +++ b/include/linux/list.h
> @@ -425,6 +425,9 @@ static inline void list_splice_init_rcu(
>  #define list_entry(ptr, type, member) \
>  	container_of(ptr, type, member)
>  
> +#define list_first_entry(ptr, type, member) \
> +	list_entry((ptr)->next, type, member)
> +

Please provide kernel-doc for that like the rest of list.h has.

>  /**
>   * list_for_each	-	iterate over a list
>   * @pos:	the &struct list_head to use as a loop cursor.


---
~Randy
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