Re: [PATCH] mm: migrate: add isolate_movable_page() stub implementation

[Michal Hocko <mhocko@kernel.org>]

JFYI, Yisheng Xie has already posted a new version of the patchset [1]
and I assume Andrew will drop the current one.

[1] http://lkml.kernel.org/r/1485356738-4831-1-git-send-email-ysxie@foxmail.com

On Wed 25-01-17 23:27:38, Arnd Bergmann wrote:
> Without CONFIG_MIGRATION, we get a build failure when trying to
> call isolate_movable_page():
> 
> mm/memory-failure.c: In function '__soft_offline_page':
> mm/memory-failure.c:1656:10: error: implicit declaration of function 'isolate_movable_page';did you mean 'isolate_huge_page'? [-Werror=implicit-function-declaration]
> 
> This adds one more static inline helper function in the header
> declaring it. This returns false to indicate that the
> page was not isolated.
> 
> Fixes: mmotm ("HWPOISON: soft offlining for non-lru movable pages")
> Fixes: bda807d44454 ("mm: migrate: support non-lru movable page migration")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
>  include/linux/migrate.h | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/include/linux/migrate.h b/include/linux/migrate.h
> index ae8d475a9385..09dd6e924106 100644
> --- a/include/linux/migrate.h
> +++ b/include/linux/migrate.h
> @@ -57,6 +57,9 @@ static inline int migrate_pages(struct list_head *l, new_page_t new,
>  		int reason)
>  	{ return -ENOSYS; }
>  
> +static inline bool isolate_movable_page(struct page *page, isolate_mode_t mode)
> +	{ return false; }
> +
>  static inline int migrate_prep(void) { return -ENOSYS; }
>  static inline int migrate_prep_local(void) { return -ENOSYS; }
>  
> -- 
> 2.9.0

-- 
Michal Hocko
SUSE Labs