Re: [PATCH 2/2 V3] MM: Discard NR_UNSTABLE_NFS, use NR_WRITEBACK instead.

[Christoph Hellwig]

On Thu, Apr 16, 2020 at 10:31:27AM +1000, NeilBrown wrote:
>  	return global_node_page_state(NR_FILE_DIRTY) +
> -		global_node_page_state(NR_UNSTABLE_NFS) +
>  		get_nr_dirty_inodes();

Nit: this could a single line now:

  	return global_node_page_state(NR_FILE_DIRTY) + get_nr_dirty_inodes();

> +		/* This page is really still in write-back - just that the
> +		 * writeback is happening on the server now.
> +		 */

This needs to switch to the canonical kernel comment style.

> +	if (off == NR_VMSTAT_ITEMS - 1) {
> +		/* We've come to the end - add any deprecated counters
> +		 * to avoid breaking userspace which might depend on
> +		 * them being present.
> +		 */

Same here.

Otherwise looks good:

Reviewed-by: Christoph Hellwig <hch@xxxxxx>