Re: [PATCH V13 01/10] mmc: core: Add parameter use_blk_mq

[Linus Walleij]

On Fri, Nov 3, 2017 at 2:20 PM, Adrian Hunter <adrian.hunter@xxxxxxxxx> wrote:

> Until mmc has blk-mq support fully implemented and tested, add a
> parameter use_blk_mq, default to false unless config option MMC_MQ_DEFAULT
> is selected.
>
> Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
(...)

> +config MMC_MQ_DEFAULT
> +       bool "MMC: use blk-mq I/O path by default"
> +       depends on MMC && BLOCK

default y

The reason being: I want it to be tested, I want it to be deployed.
We should rather use it as a fallback option if something turns out
to be problematic with MQ which, at this point, is highly unlikely.

> +++ b/include/linux/mmc/host.h
> @@ -380,6 +380,7 @@ struct mmc_host {
>         unsigned int            doing_retune:1; /* re-tuning in progress */
>         unsigned int            retune_now:1;   /* do re-tuning at next req */
>         unsigned int            retune_paused:1; /* re-tuning is temporarily disabled */
> +       unsigned int            use_blk_mq:1;   /* use blk-mq */

unsigned int foo:1 is really a weird way of saying "bool".

We should just fix it I guess, but it's another patch.

Yours,
Linus Walleij