Re: [PATCH] counting bounce buffer in vmstat

[Andrew Morton <akpm@osdl.org>]

KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> wrote:
>
> diff -puN include/linux/page-flags.h~count_bounce include/linux/page-flags.h
>  --- linux-2.6.12-rc2-mm3/include/linux/page-flags.h~count_bounce	2005-04-27 10:23:15.000000000 +0900
>  +++ linux-2.6.12-rc2-mm3-kamezawa/include/linux/page-flags.h	2005-04-27 10:24:11.000000000 +0900
>  @@ -89,6 +89,7 @@ struct page_state {
>   	unsigned long nr_page_table_pages;/* Pages used for pagetables */
>   	unsigned long nr_mapped;	/* mapped into pagetables */
>   	unsigned long nr_slab;		/* In slab */
>  +	unsigned long nr_bounce;	/* pages for bounce buffers */
>   #define GET_PAGE_STATE_LAST nr_slab

That's not really right.

There are two functions: get_page_state() and get_full_page_state(). 
get_page_state() only gets those fields up to and including
GET_PAGE_STATE_LAST.  The way you have the code laid out there implies that
get_page_state() also calculates the total nr_bounce, only it doesn't.

I'll fix it up.