[PATCH] atomic64: No need for CONFIG_ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE

Vineet Gupta Vineet.Gupta1 at synopsys.com
Thu Sep 8 11:34:29 PDT 2016


On 09/08/2016 11:19 AM, Peter Zijlstra wrote:
> 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?

Please do. ARCv2 patch (following shortly) doesn't need it - I selected the
option in orig patch - which I can just take out.

Thx,
-Vineet



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