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SubjectRe: [PATCH 00/10] jump label: introduce very_[un]likely + cleanups + docs
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Stupid thought... do we have cases that matter where the bias and default don't agree?

Ingo Molnar <mingo@elte.hu> wrote:

>
>* Ingo Molnar <mingo@elte.hu> wrote:
>
>> But it is fundamentally mixing execution and *data type* and
>> it is not conveying the build time bias properly.
>>
>> So the best high level naming would be something like:
>>
>> struct static_condition static_flag = STATIC_COND_FALSE;
>>
>>
>> if (very_unlikely(&static_flag)) {
>> ...
>> }
>>
>> ...
>>
>> static_cond_inc(&static_flag);
>> ...
>> static_cond_dec(&static_flag);
>
>Btw., I think the modification path could also carry the high
>cost of modification (stopping all cpus, modifying code, etc.).
>
>This could be done via:
>
> static_cond_slow_inc(&static_flag);
> ...
> static_cond_slow_dec(&static_flag);
>
>And if a developer does not notice that 'slow' implies a
>performance cost, then he probably would have doubly missed this
>aspect of jump_label_inc()/jump_label_dec().
>
>Thanks,
>
> Ingo

--
Sent from my mobile phone. Please excuse my brevity and lack of formatting.


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