Re: [PATCH -v4 RESEND 6/9] mm, THP, swap: Support to add/delete THP to/from swap cache

[Hillf Danton]

On Friday, October 28, 2016 1:56 PM Huang, Ying wrote:
> 
> @@ -109,9 +118,16 @@ int __add_to_swap_cache(struct page *page, swp_entry_t entry)
>  		 * So add_to_swap_cache() doesn't returns -EEXIST.
>  		 */
>  		VM_BUG_ON(error == -EEXIST);
> -		set_page_private(page, 0UL);
>  		ClearPageSwapCache(page);
> -		put_page(page);
> +		set_page_private(cur_page, 0UL);
> +		while (i--) {
> +			cur_page--;
> +			cur_entry.val--;
> +			set_page_private(cur_page, 0UL);
> +			radix_tree_delete(&address_space->page_tree,
> +					  swp_offset(cur_entry));
> +		}

Pull pages out of radix tree with tree lock held?

> +		page_ref_sub(page, nr);
>  	}
> 
>  	return error;
>