Re: [Xen-devel] [PATCH] xen/balloon: add runtime control for scrubbing ballooned out pages

[Jan Beulich]

>>> On 06.09.18 at 17:33, <marmarek@xxxxxxxxxxxxxxxxxxxxxx> wrote:
> --- a/include/xen/mem-reservation.h
> +++ b/include/xen/mem-reservation.h
> @@ -17,12 +17,17 @@
>  
>  #include <xen/page.h>
>  
> +#ifdef CONFIG_XEN_SCRUB_PAGES
> +extern bool xen_scrub_pages;
> +
>  static inline void xenmem_reservation_scrub_page(struct page *page)
>  {
> -#ifdef CONFIG_XEN_SCRUB_PAGES
> -	clear_highpage(page);
> -#endif
> +	if (xen_scrub_pages)
> +		clear_highpage(page);
>  }
> +#else
> +static inline void xenmem_reservation_scrub_page(struct page *page) { }
> +#endif

Wouldn't CONFIG_XEN_SCRUB_PAGES then better become
CONFIG_XEN_SCRUB_PAGES_DEFAULT, with the value used as
initializer of xen_scrub_pages?

Jan