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SubjectRe: [PATCH] x86: percpu_to_op() misses memory and flags clobbers
Jeremy Fitzhardinge a écrit :
> Eric Dumazet wrote:
>> +#define percpu_inc(var) percpu_to_op0("inc", per_cpu__##var)
>> +#define percpu_dec(var) percpu_to_op0("dec", per_cpu__##var)
>>
>
> There's probably not a lot of value in this. The Intel and AMD
> optimisation guides tend to deprecate inc/dec in favour of using
> add/sub, because the former can cause pipeline stalls due to its partial
> flags update.
>
> J

Sure, but this saves one byte per call, this is probably why we still use
inc/dec in so many places...

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