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Subject: Re: [Patch v2 2/4] mm/migrate.c: wrap do_move_pages_to_node() and
 store_status()
To:     Wei Yang <richardw.yang@linux.intel.com>, akpm@linux-foundation.org
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org, mhocko@suse.com,
        yang.shi@linux.alibaba.com, rientjes@google.com
References: <20200122011647.13636-1-richardw.yang@linux.intel.com>
 <20200122011647.13636-3-richardw.yang@linux.intel.com>
From:   David Hildenbrand <david@redhat.com>
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Date:   Tue, 28 Jan 2020 11:14:55 +0100
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On 22.01.20 02:16, Wei Yang wrote:
> Usually do_move_pages_to_node() and store_status() is a pair. There are
> three places call this pair of functions with almost the same form.

I'd suggest

"
Usually, do_move_pages_to_node() and store_status() are used in
combination. We have three similar call sites.

Let's provide a wrapper for both function calls -
move_pages_and_store_status - to make the calling code easier to
maintain and fix (as noted by Yang Shi, the return value handling of
do_move_pages_to_node() has a flaw).
"

> 
> This patch just wrap it to make it friendly to audience and also
> consolidate the move and store action into one place. Also mentioned by
> Yang Shi, the handling of do_move_pages_to_node()'s return value is not
> proper. Now we can fix it in one place.
> 
> Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
> Acked-by: Michal Hocko <mhocko@suse.com>
> ---
>  mm/migrate.c | 30 +++++++++++++++++++-----------
>  1 file changed, 19 insertions(+), 11 deletions(-)
> 
> diff --git a/mm/migrate.c b/mm/migrate.c
> index 4c2a21856717..a4d3bd6475e1 100644
> --- a/mm/migrate.c
> +++ b/mm/migrate.c
> @@ -1583,6 +1583,19 @@ static int add_page_for_migration(struct mm_struct *mm, unsigned long addr,
>  	return err;
>  }
>  
> +static int move_pages_and_store_status(struct mm_struct *mm, int node,
> +		struct list_head *pagelist, int __user *status,
> +		int start, int nr)

nit: indentation

> +{
> +	int err;
> +
> +	err = do_move_pages_to_node(mm, pagelist, node);
> +	if (err)
> +		return err;
> +	err = store_status(status, start, node, nr);
> +	return err;

return store_status(status, start, node, nr);

directly


Apart from that (and some more indentation nits)

Reviewed-by: David Hildenbrand <david@redhat.com>


-- 
Thanks,

David / dhildenb