lkml.org 
[lkml]   [2017]   [Apr]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [RFC 1/2] mm: Uncharge poisoned pages
Date
On Thu, Apr 20, 2017 at 11:26:01AM +0200, Laurent Dufour wrote:
> When page are poisoned, they should be uncharged from the root memory
> cgroup.

Could you include some information about what problem this patch tries
to solve?
# I know that you already explain it in patch 0/2, so you can simply
# copy from it.

>
> Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
> ---
> mm/memory-failure.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/mm/memory-failure.c b/mm/memory-failure.c
> index 27f7210e7fab..00bd39d3d4cb 100644
> --- a/mm/memory-failure.c
> +++ b/mm/memory-failure.c
> @@ -530,6 +530,7 @@ static const char * const action_page_types[] = {
> static int delete_from_lru_cache(struct page *p)
> {
> if (!isolate_lru_page(p)) {
> + memcg_kmem_uncharge(p, 0);

This function is supposed to be called with if (memcg_kmem_enabled()) check,
so could you do like below?

+ if (memcg_kmem_enabled())
+ memcg_kmem_uncharge(p, 0);


And I feel that we can call this function outside if (!isolate_lru_page(p))
block, because isolate_lru_page could fail and then the error page is left
incompletely isolated. Such error page has PageHWPoison set, so I guess that
the reported bug still triggers on such case.

Thanks,
Naoya Horiguchi

\
 
 \ /
  Last update: 2017-04-24 11:08    [W:0.065 / U:0.608 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site