Re: [PATCH] mm: unhide vmstat_text definition for CONFIG_SMP

Michal Hocko
2016-05-16T07:31:47Z

On Wed 11-05-16 10:32:11, Christoph Lameter wrote:
> Subject: Do not build vmstat_refresh if there is no procfs support
>
> It makes no sense to build functionality into the kernel that
> cannot be used and causes build issues.
>
> Signed-off-by: Christoph Lameter <cl@linux.com>
>
> Index: linux/mm/vmstat.c
> ===================================================================
> --- linux.orig/mm/vmstat.c
> +++ linux/mm/vmstat.c
> @@ -1358,7 +1358,6 @@ static const struct file_operations proc
> .llseek = seq_lseek,
> .release = seq_release,
> };
> -#endif /* CONFIG_PROC_FS */
>
> #ifdef CONFIG_SMP
> static struct workqueue_struct *vmstat_wq;

This doesn't work because it makes the whole vmstat_wq depend on
CONFIG_PROC_FS. Which is obviously bad because we both rely on doing the
periodic sync even when counters are not exported to the userspace and
it wound't compile anyway...
--
Michal Hocko
SUSE Labs