> A patch to change to page accounting code (in v4.8-rc1) conflicts with
> a change to lustre (in staging-next for v4.9), and fortunately gets
> detected using a gcc warning:
>
> In file included from /git/arm-soc/include/linux/mm.h:1001:0,
> from /git/arm-soc/include/linux/highmem.h:7,
> from /git/arm-soc/drivers/staging/lustre/lustre/osc/../../include/linux/libcfs/linux/libcfs.h:46,
> from /git/arm-soc/drivers/staging/lustre/lustre/osc/../../include/linux/libcfs/libcfs.h:36,
> from /git/arm-soc/drivers/staging/lustre/lustre/osc/osc_cl_internal.h:45,
> from /git/arm-soc/drivers/staging/lustre/lustre/osc/osc_page.c:40:
> drivers/staging/lustre/lustre/osc/osc_page.c: In function 'unstable_page_accounting':
> include/linux/vmstat.h:117:2: error: array subscript is above array bounds [-Werror=array-bounds]
> atomic_long_add(x, &vm_zone_stat[item]);
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/vmstat.h:117:2: error: array subscript is above array bounds [-Werror=array-bounds]
> atomic_long_add(x, &vm_zone_stat[item]);
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> This changes the function to use the correct interface for accounting in the
> "node" rather than the "zone".
>
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> Fixes: d806f30e639b ("staging: lustre: osc: revise unstable pages accounting")
> Fixes: 11fb998986a7 ("mm: move most file-based accounting to the node")
Thanks for fixing things. I couldn't reproduce this problem on x86.
Reviewed-by: James Simmons <jsimmons@xxxxxxxxxxxxx>
> ---
> drivers/staging/lustre/lustre/osc/osc_page.c | 14 +++++++-------
> 1 file changed, 7 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/staging/lustre/lustre/osc/osc_page.c b/drivers/staging/lustre/lustre/osc/osc_page.c
> index 583a0af2d388..c8889eabc402 100644
> --- a/drivers/staging/lustre/lustre/osc/osc_page.c
> +++ b/drivers/staging/lustre/lustre/osc/osc_page.c
> @@ -789,7 +789,7 @@ out:
>
> /**
> * Atomic operations are expensive. We accumulate the accounting for the
> - * same page zone to get better performance.
> + * same page pgdat to get better performance.
> * In practice this can work pretty good because the pages in the same RPC
> * are likely from the same page zone.
> */
> @@ -797,28 +797,28 @@ static inline void unstable_page_accounting(struct ptlrpc_bulk_desc *desc,
> int factor)
> {
> int page_count = desc->bd_iov_count;
> - void *zone = NULL;
> + pg_data_t *last = NULL;
> int count = 0;
> int i;
>
> for (i = 0; i < page_count; i++) {
> - void *pz = page_zone(desc->bd_iov[i].bv_page);
> + pg_data_t *pgdat = page_pgdat(desc->bd_iov[i].bv_page);
>
> - if (likely(pz == zone)) {
> + if (likely(pgdat == last)) {
> ++count;
> continue;
> }
>
> if (count > 0) {
> - mod_zone_page_state(zone, NR_UNSTABLE_NFS,
> + mod_node_page_state(pgdat, NR_UNSTABLE_NFS,
> factor * count);
> count = 0;
> }
> - zone = pz;
> + last = pgdat;
> ++count;
> }
> if (count > 0)
> - mod_zone_page_state(zone, NR_UNSTABLE_NFS, factor * count);
> + mod_node_page_state(last, NR_UNSTABLE_NFS, factor * count);
> }
>
> static inline void add_unstable_page_accounting(struct ptlrpc_bulk_desc *desc)
> --
> 2.9.0
>
>
_______________________________________________
devel mailing list
devel@xxxxxxxxxxxxxxxxxxxxxx
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
