Re: [BUGFIX][PATCH] fix bad page removal from LRU (Was Re: [RFC][PATCH] cgroup: fix permanent wait in rmdir

[Balbir Singh <balbir@linux.vnet.ibm.com>]

* KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> [2009-06-23 08:57:55]:

> I think this is a fix for the problem. Sorry for regression.
> fix for "memcg: fix lru rotation in isolate_pages" patch in 2.6.30-git18.
> 
> ==
> From: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
> 
> A page isolated is "cursor_page" not "page".
> This causes list corruption finally.
> 
> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
> ---
>  mm/vmscan.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> Index: linux-2.6.30-git18/mm/vmscan.c
> ===================================================================
> --- linux-2.6.30-git18.orig/mm/vmscan.c
> +++ linux-2.6.30-git18/mm/vmscan.c
> @@ -932,7 +932,7 @@ static unsigned long isolate_lru_pages(u
>  				continue;
>  			if (__isolate_lru_page(cursor_page, mode, file) == 0) {
>  				list_move(&cursor_page->lru, dst);
> -				mem_cgroup_del_lru(page);
> +				mem_cgroup_del_lru(cursor_page);
>  				nr_taken++;
>  				scan++;
>  			}

Good catch!

Reviewed-by: Balbir Singh <balbir@linux.vnet.ibm.com>

-- 
	Balbir