On Tue, Jan 31, 2023, at 09:47, Linus Walleij wrote:
> If we enable the MMC/SD block layer, use Kconfig to imply the BFQ
> I/O scheduler.
>
> As all MMC/SD devices are single-queue, this is the scheduler that
> users want so let's be helpful and make sure it gets
> default-selected into a manual kernel configuration. It will still
> need to be enabled at runtime (usually with udev scripts).
>
> Cc: linux-block@xxxxxxxxxxxxxxx
> Cc: Paolo Valente <paolo.valente@xxxxxxxxxx>
> Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
> ---
> drivers/mmc/core/Kconfig | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/mmc/core/Kconfig b/drivers/mmc/core/Kconfig
> index 6f25c34e4fec..52fe9d7c21cc 100644
> --- a/drivers/mmc/core/Kconfig
> +++ b/drivers/mmc/core/Kconfig
> @@ -37,6 +37,7 @@ config PWRSEQ_SIMPLE
> config MMC_BLOCK
> tristate "MMC block device driver"
> depends on BLOCK
> + imply IOSCHED_BFQ
As with most other uses of 'imply', this one does not do what you
think it does. Enabling MMC_BLOCK in 'make menuconfig' or similar
won't actually turn on IOSCHED_BFQ implicitly. The only difference
this makes is that it gets enabled in a 'make defconfig' run when
IOSCHED_BFQ is not already configured.
Just put it into the defconfig files instead.
Arnd
