Re: [RFC] block: deprecate choosing elevator via boot param

[Oleksandr Natalenko]

Jens,

any thoughts about this?

On Mon, Aug 14, 2017 at 11:27 AM, Oleksandr Natalenko
<oleksandr@xxxxxxxxxx> wrote:
> Setting I/O scheduler via kernel command line is not flexible enough
> anymore. Different schedulers might be desirable for different types
> of devices (SSDs and HDDs, for instance). Moreover, setting elevator
> while using blk-mq framework does not work in this way already.
>
> This commit enables warning if user specifies "elevator" boot param.
> Removing this option at all might be considered in some future.
>
> Signed-off-by: Oleksandr Natalenko <oleksandr@xxxxxxxxxx>
> ---
>  block/elevator.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/block/elevator.c b/block/elevator.c
> index 4bb2f0c93fa6..9ade7e12e417 100644
> --- a/block/elevator.c
> +++ b/block/elevator.c
> @@ -130,6 +130,9 @@ static int __init elevator_setup(char *str)
>          * Be backwards-compatible with previous kernels, so users
>          * won't get the wrong elevator.
>          */
> +       printk(KERN_WARNING
> +               "Setting I/O scheduler via kernel command line " \
> +               "is deprecated. Use udev rule instead.");
>         strncpy(chosen_elevator, str, sizeof(chosen_elevator) - 1);
>         return 1;
>  }
> --
> 2.14.1
>



-- 
Best regards,
  Oleksandr Natalenko (post-factum)
  Software Maintenance Engineer