Re: [PATCH 2/2] sysctl: remove /proc/sys/vm/nr_pdflush_threads

[Rakesh Pandit]

Hi Jens,

On Tue, Oct 03, 2017 at 09:16:21AM -0600, Jens Axboe wrote:
> This tunable has been obsolete since 2.6.32, and writes to the
> file have been failing and complaining in dmesg since then:
> 
> nr_pdflush_threads exported in /proc is scheduled for removal
> 
> That was 8 years ago. Remove the file ABI obsolete notice, and
> the sysfs file.
> 
> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
> ---
>  Documentation/ABI/obsolete/proc-sys-vm-nr_pdflush_threads | 5 -----
>  kernel/sysctl.c                                           | 5 -----
>  2 files changed, 10 deletions(-)
>  delete mode 100644 Documentation/ABI/obsolete/proc-sys-vm-nr_pdflush_threads
> 
> diff --git a/Documentation/ABI/obsolete/proc-sys-vm-nr_pdflush_threads b/Documentation/ABI/obsolete/proc-sys-vm-nr_pdflush_threads
> deleted file mode 100644
> index b0b0eeb20fe3..000000000000
> --- a/Documentation/ABI/obsolete/proc-sys-vm-nr_pdflush_threads
> +++ /dev/null
> @@ -1,5 +0,0 @@
> -What:		/proc/sys/vm/nr_pdflush_threads
> -Date:		June 2012
> -Contact:	Wanpeng Li <liwp@xxxxxxxxxxxxxxxxxx>
> -Description: Since pdflush is replaced by per-BDI flusher, the interface of old pdflush
> -             exported in /proc/sys/vm/ should be removed.
> diff --git a/kernel/sysctl.c b/kernel/sysctl.c
> index 6648fbbb8157..a5dd8d82c253 100644
> --- a/kernel/sysctl.c
> +++ b/kernel/sysctl.c
> @@ -1345,11 +1345,6 @@ static struct ctl_table vm_table[] = {
>  		.extra1		= &zero,
>  	},
>  	{
> -		.procname       = "nr_pdflush_threads",
> -		.mode           = 0444 /* read-only */,
> -		.proc_handler   = pdflush_proc_obsolete,

It seems you forgot to remove pdflush_proc_obsolete from:
./include/linux/backing-dev.h
./mm/backing-dev.c

Best regards,
	Rakesh Pandit