On Tue 13-11-18 16:04:36, Wei Yang wrote:
> Commit fa5e084e43eb ("vmscan: do not unconditionally treat zones that
> fail zone_reclaim() as full") changed the return value of node_reclaim().
> The original return value 0 means NODE_RECLAIM_SOME after this commit.
>
> While the return value of node_reclaim() when CONFIG_NUMA is n is not
> changed. This will leads to call zone_watermark_ok() again.
>
> This patch fix the return value by adjusting to NODE_RECLAIM_NOSCAN. Since
> node_reclaim() is only called in page_alloc.c, move it to mm/internal.h.
The issue should be cosmetic but the code consistency is definitely an
improvement. Moving this from swap.h makes a lot of sense as well.
> Signed-off-by: Wei Yang <richard.weiyang@xxxxxxxxx>
Acked-by: Michal Hocko <mhocko@xxxxxxxx>
> ---
> v2: move node_reclaim() to mm/internal.h
> ---
> include/linux/swap.h | 6 ------
> mm/internal.h | 10 ++++++++++
> 2 files changed, 10 insertions(+), 6 deletions(-)
>
> diff --git a/include/linux/swap.h b/include/linux/swap.h
> index d8a07a4f171d..065988c27373 100644
> --- a/include/linux/swap.h
> +++ b/include/linux/swap.h
> @@ -358,14 +358,8 @@ extern unsigned long vm_total_pages;
> extern int node_reclaim_mode;
> extern int sysctl_min_unmapped_ratio;
> extern int sysctl_min_slab_ratio;
> -extern int node_reclaim(struct pglist_data *, gfp_t, unsigned int);
> #else
> #define node_reclaim_mode 0
> -static inline int node_reclaim(struct pglist_data *pgdat, gfp_t mask,
> - unsigned int order)
> -{
> - return 0;
> -}
> #endif
>
> extern int page_evictable(struct page *page);
> diff --git a/mm/internal.h b/mm/internal.h
> index 291eb2b6d1d8..6a57811ae47d 100644
> --- a/mm/internal.h
> +++ b/mm/internal.h
> @@ -444,6 +444,16 @@ static inline void mminit_validate_memmodel_limits(unsigned long *start_pfn,
> #define NODE_RECLAIM_SOME 0
> #define NODE_RECLAIM_SUCCESS 1
>
> +#ifdef CONFIG_NUMA
> +extern int node_reclaim(struct pglist_data *, gfp_t, unsigned int);
> +#else
> +static inline int node_reclaim(struct pglist_data *pgdat, gfp_t mask,
> + unsigned int order)
> +{
> + return NODE_RECLAIM_NOSCAN;
> +}
> +#endif
> +
> extern int hwpoison_filter(struct page *p);
>
> extern u32 hwpoison_filter_dev_major;
> --
> 2.15.1
--
Michal Hocko
SUSE Labs
