Re: [PATCH] atomic64: No need for CONFIG_ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE

Peter Zijlstra
2016-09-08T18:19:59Z

On Thu, Sep 08, 2016 at 09:28:18AM -0700, Vineet Gupta wrote:
> This came to light when implementing native 64-bit atomics for ARCv2.
>
> The atomic64 self-test code uses CONFIG_ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
> to check whether atomic64_dec_if_positive() is available.
> It seems it was needed when not every arch defined it.
> However as of current code the Kconfig option seems needless
>
> - for CONFIG_GENERIC_ATOMIC64 it is auto-enabled in lib/Kconfig and a
> generic definition of API is present lib/atomic64.c
> - arches with native 64-bit atomics select it in arch/*/Kconfig and
> define the API in their headers
>
> So I see no point in keeping the Kconfig option
>
> Compile tested for 2 representatives:
> - blackfin (CONFIG_GENERIC_ATOMIC64)
> - x86 (!CONFIG_GENERIC_ATOMIC64)
>
> Also logistics wise it seemed simpler to just do this in 1 patch vs.
> splitting per arch - but I can break it up if maintainer feel that
> is better to avoid conflicts.

Works for me; you want me to take this, or do you need it for you ARCv2
patches?