Re: [PATCH] mm: compaction: Abort compaction if too many pages areisolated and caller is asynchronous

From: Andrea Arcangeli
Date: Tue May 31 2011 - 08:25:26 EST


On Tue, May 31, 2011 at 09:16:20PM +0900, Minchan Kim wrote:
> I am not sure this is related to the problem you have seen.
> If he used hwpoison by madivse, it is possible.

CONFIG_ARCH_SUPPORTS_MEMORY_FAILURE=y
# CONFIG_MEMORY_FAILURE is not set

> Anyway, we can see negative value by count mismatch in UP build.
> Let's fix it.

Definitely let's fix it, but it's probably not related to this one.

>
> From 1d3ebce2e8aa79dcc912da16b7a8d0611b6f9f1a Mon Sep 17 00:00:00 2001
> From: Minchan Kim <minchan.kim@xxxxxxxxx>
> Date: Tue, 31 May 2011 21:11:58 +0900
> Subject: [PATCH] Fix page isolated count mismatch
>
> If migration is failed, normally we call putback_lru_pages which
> decreases NR_ISOLATE_[ANON|FILE].
> It means we should increase NR_ISOLATE_[ANON|FILE] before calling
> putback_lru_pages. But soft_offline_page dosn't it.
>
> It can make NR_ISOLATE_[ANON|FILE] with negative value and in UP build,
> zone_page_state will say huge isolated pages so too_many_isolated
> functions be deceived completely. At last, some process stuck in D state
> as it expect while loop ending with congestion_wait.
> But it's never ending story.
>
> If it is right, it would be -stable stuff.
>
> Cc: Mel Gorman <mel@xxxxxxxxx>
> Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx>
> Signed-off-by: Minchan Kim <minchan.kim@xxxxxxxxx>
> ---
> mm/memory-failure.c | 4 +++-
> 1 files changed, 3 insertions(+), 1 deletions(-)
>
> diff --git a/mm/memory-failure.c b/mm/memory-failure.c
> index 5c8f7e0..eac0ba5 100644
> --- a/mm/memory-failure.c
> +++ b/mm/memory-failure.c
> @@ -52,6 +52,7 @@
> #include <linux/swapops.h>
> #include <linux/hugetlb.h>
> #include <linux/memory_hotplug.h>
> +#include <linux/mm_inline.h>
> #include "internal.h"
>
> int sysctl_memory_failure_early_kill __read_mostly = 0;
> @@ -1468,7 +1469,8 @@ int soft_offline_page(struct page *page, int flags)
> put_page(page);
> if (!ret) {
> LIST_HEAD(pagelist);
> -
> + inc_zone_page_state(page, NR_ISOLATED_ANON +
> + page_is_file_cache(page));
> list_add(&page->lru, &pagelist);
> ret = migrate_pages(&pagelist, new_page, MPOL_MF_MOVE_ALL,
> 0, true);

Reviewed-by: Andrea Arcangeli <aarcange@xxxxxxxxxx>

Let's check all other migrate_pages callers too...
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