On 20-07-01 08:26:24, Dave Hansen wrote:
>
> From: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
>
> It is currently not obvious that the RECLAIM_* bits are part of the
> uapi since they are defined in vmscan.c. Move them to a uapi header
> to make it obvious.
>
> This should have no functional impact.
>
> Signed-off-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
> Cc: Ben Widawsky <ben.widawsky@xxxxxxxxx>
> Cc: Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx>
> Cc: Daniel Wagner <dwagner@xxxxxxx>
> Cc: "Tobin C. Harding" <tobin@xxxxxxxxxx>
> Cc: Christoph Lameter <cl@xxxxxxxxx>
> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> Cc: Huang Ying <ying.huang@xxxxxxxxx>
> Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
> Cc: Qian Cai <cai@xxxxxx>
> Cc: Daniel Wagner <dwagner@xxxxxxx>
>
> --
>
> Note: This is not cc'd to stable. It does not fix any bugs.
> ---
>
> b/include/uapi/linux/mempolicy.h | 7 +++++++
> b/mm/vmscan.c | 8 --------
> 2 files changed, 7 insertions(+), 8 deletions(-)
>
> diff -puN include/uapi/linux/mempolicy.h~mm-vmscan-move-RECLAIM-bits-to-uapi include/uapi/linux/mempolicy.h
> --- a/include/uapi/linux/mempolicy.h~mm-vmscan-move-RECLAIM-bits-to-uapi 2020-07-01 08:22:12.502955333 -0700
> +++ b/include/uapi/linux/mempolicy.h 2020-07-01 08:22:12.508955333 -0700
> @@ -62,5 +62,12 @@ enum {
> #define MPOL_F_MOF (1 << 3) /* this policy wants migrate on fault */
> #define MPOL_F_MORON (1 << 4) /* Migrate On protnone Reference On Node */
>
> +/*
> + * These bit locations are exposed in the vm.zone_reclaim_mode sysctl
> + * ABI. New bits are OK, but existing bits can never change.
> + */
> +#define RECLAIM_ZONE (1<<0) /* Run shrink_inactive_list on the zone */
> +#define RECLAIM_WRITE (1<<1) /* Writeout pages during reclaim */
> +#define RECLAIM_UNMAP (1<<2) /* Unmap pages during reclaim */
Have you considered turning this into an enum while moving it?
>
> #endif /* _UAPI_LINUX_MEMPOLICY_H */
> diff -puN mm/vmscan.c~mm-vmscan-move-RECLAIM-bits-to-uapi mm/vmscan.c
> --- a/mm/vmscan.c~mm-vmscan-move-RECLAIM-bits-to-uapi 2020-07-01 08:22:12.504955333 -0700
> +++ b/mm/vmscan.c 2020-07-01 08:22:12.509955333 -0700
> @@ -4091,14 +4091,6 @@ module_init(kswapd_init)
> int node_reclaim_mode __read_mostly;
>
> /*
> - * These bit locations are exposed in the vm.zone_reclaim_mode sysctl
> - * ABI. New bits are OK, but existing bits can never change.
> - */
> -#define RECLAIM_ZONE (1<<0) /* Run shrink_inactive_list on the zone */
> -#define RECLAIM_WRITE (1<<1) /* Writeout pages during reclaim */
> -#define RECLAIM_UNMAP (1<<2) /* Unmap pages during reclaim */
> -
> -/*
> * Priority for NODE_RECLAIM. This determines the fraction of pages
> * of a node considered for each zone_reclaim. 4 scans 1/16th of
> * a zone.
> _
