Re: [PATCH v2] mm: memory-failure: kill __soft_offline_page()

[Anshuman Khandual <anshuman.khandual@arm.com>]

On 8/30/22 16:16, Kefeng Wang wrote:
> Squash the __soft_offline_page() into soft_offline_in_use_page() and kill
> __soft_offline_page().
> 
> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
> Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>

Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>

> ---
> v2: update hpage when try_to_split_thp_page() success
> 
>  mm/memory-failure.c | 25 ++++++++++---------------
>  1 file changed, 10 insertions(+), 15 deletions(-)
> 
> diff --git a/mm/memory-failure.c b/mm/memory-failure.c
> index b61f2de9f2a1..df54a6bc9bef 100644
> --- a/mm/memory-failure.c
> +++ b/mm/memory-failure.c
> @@ -2434,11 +2434,11 @@ static bool isolate_page(struct page *page, struct list_head *pagelist)
>  }
>  
>  /*
> - * __soft_offline_page handles hugetlb-pages and non-hugetlb pages.
> + * soft_offline_in_use_page handles hugetlb-pages and non-hugetlb pages.
>   * If the page is a non-dirty unmapped page-cache page, it simply invalidates.
>   * If the page is mapped, it migrates the contents over.
>   */
> -static int __soft_offline_page(struct page *page)
> +static int soft_offline_in_use_page(struct page *page)
>  {
>  	long ret = 0;
>  	unsigned long pfn = page_to_pfn(page);
> @@ -2451,6 +2451,14 @@ static int __soft_offline_page(struct page *page)
>  		.gfp_mask = GFP_USER | __GFP_MOVABLE | __GFP_RETRY_MAYFAIL,
>  	};
>  
> +	if (!huge && PageTransHuge(hpage)) {
> +		if (try_to_split_thp_page(page)) {
> +			pr_info("soft offline: %#lx: thp split failed\n", pfn);
> +			return -EBUSY;
> +		}
> +		hpage = page;
> +	}
> +
>  	lock_page(page);
>  	if (!PageHuge(page))
>  		wait_on_page_writeback(page);
> @@ -2500,19 +2508,6 @@ static int __soft_offline_page(struct page *page)
>  	return ret;
>  }
>  
> -static int soft_offline_in_use_page(struct page *page)
> -{
> -	struct page *hpage = compound_head(page);
> -
> -	if (!PageHuge(page) && PageTransHuge(hpage))
> -		if (try_to_split_thp_page(page) < 0) {
> -			pr_info("soft offline: %#lx: thp split failed\n",
> -				page_to_pfn(page));
> -			return -EBUSY;
> -		}
> -	return __soft_offline_page(page);
> -}
> -
>  static void put_ref_page(struct page *page)
>  {
>  	if (page)