Re: [PATCH 6/6] zram: export new 'mm_stat' sysfs attrs

[Minchan Kim <minchan@kernel.org>]

On Wed, Mar 11, 2015 at 12:08:34AM +0900, Sergey Senozhatsky wrote:
> Per-device `zram<id>/mm_stat' file provides accumulated mm statistics
> of particular zram device in a format similar to block layer statistics.
> The file consists of a single line and represents the following stats
> (separated by whitespace):
> 	orig_data_size
> 	compr_data_size
> 	mem_used_total
> 	mem_limit
> 	mem_used_max
> 	zero_pages
> 	num_migrated
> 
> Since now we have three stat files (block layer zram<id>/stat,
> zram<id>/io_stat and zram<id>/mm_stat) document WARNING about
> per-stat sysfs nodes being deprecated.

Any user doesn't take care of document. I think we should add
pr_warn_once to notify the user if he tried deprecated interface.
In addition, we should add deprecated interface in Documentation/ABI/obsolete/

> 
> Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
> ---
>  Documentation/ABI/testing/sysfs-block-zram |  8 ++++++++
>  Documentation/blockdev/zram.txt            | 18 +++++++++++++++++
>  drivers/block/zram/zram_drv.c              | 31 ++++++++++++++++++++++++++++++
>  3 files changed, 57 insertions(+)
> 
> diff --git a/Documentation/ABI/testing/sysfs-block-zram b/Documentation/ABI/testing/sysfs-block-zram
> index a7f622f..8114c81 100644
> --- a/Documentation/ABI/testing/sysfs-block-zram
> +++ b/Documentation/ABI/testing/sysfs-block-zram
> @@ -158,3 +158,11 @@ Description:
>  		statistics not accounted by block layer. For example,
>  		failed_reads, failed_writes, etc. File format is similar to
>  		block layer statistics file format.
> +
> +What:		/sys/block/zram<id>/mm_stat
> +Date:		August 2015
> +Contact:	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
> +Description:
> +		The mm_stat file is read-only and accumulates device's mm
> +		statistics (orig_data_size, compr_data_size, etc.) in a format

Every field in mm_stat doesn't mean accumulation.

-- 
Kind regards,
Minchan Kim