Re: [PATCH v4 3/4] mm/pageblock: work around multiple arch's cmpxchg support issue

[Max Filippov]

On Thu, Sep 3, 2020 at 12:01 AM Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx> wrote:
>
> Armv6, sh2, sparc32 and xtensa can not do cmpxchg1, so we have to use
> cmpxchg4 on it.

[...]

> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig> index e00d94b16658..03a6c7fd999d 100644
> --- a/arch/arm/Kconfig
> +++ b/arch/arm/Kconfig
> @@ -48,6 +48,7 @@ config ARM
>         select GENERIC_ALLOCATOR
>         select GENERIC_ARCH_TOPOLOGY if ARM_CPU_TOPOLOGY
>         select GENERIC_ATOMIC64 if CPU_V7M || CPU_V6 || !CPU_32v6K || !AEABI
> +       select NO_CMPXCHG_BYTE if CPU_V6
>         select GENERIC_CLOCKEVENTS_BROADCAST if SMP
>         select GENERIC_CPU_AUTOPROBE
>         select GENERIC_EARLY_IOREMAP
> diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
> index d20927128fce..4c7f0ad5b93f 100644
> --- a/arch/sh/Kconfig
> +++ b/arch/sh/Kconfig
> @@ -155,6 +155,7 @@ menu "System type"
>  config CPU_SH2
>         bool
>         select SH_INTC
> +       select NO_CMPXCHG_BYTE
>
>  config CPU_SH2A
>         bool
> diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
> index efeff2c896a5..51ae5c8ede87 100644
> --- a/arch/sparc/Kconfig
> +++ b/arch/sparc/Kconfig
> @@ -58,6 +58,7 @@ config SPARC32
>         select CLZ_TAB
>         select HAVE_UID16
>         select OLD_SIGACTION
> +       select NO_CMPXCHG_BYTE
>
>  config SPARC64
>         def_bool 64BIT
> diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
> index e997e0119c02..862b008ab09e 100644
> --- a/arch/xtensa/Kconfig
> +++ b/arch/xtensa/Kconfig
> @@ -42,6 +42,7 @@ config XTENSA
>         select MODULES_USE_ELF_RELA
>         select PERF_USE_VMALLOC
>         select VIRT_TO_BUS
> +       select NO_CMPXCHG_BYTE

Please keep the lists of select statements in Kconfig files above
alphabetically sorted.

-- 
Thanks.
-- Max