Subj : Re: A question about atomic_ptr
To   : comp.programming.threads
From : Peter Dimov
Date : Sun Apr 17 2005 07:49 pm

Chris Thomasson wrote:
>> ac_i686_lfgc_smr_activate_reload:
>>  mov eax, [ecx]
>>  mov [edx], eax
>>  mfence
>>  cmp eax, [ecx]
>>  jne ac_i686_lfgc_smr_activate_reload
>>
>> Have you tried lock mov [edx], eax or lock cmp eax, [ecx]?
>
> Yes. You "should" try to avoid using that prefix. No need to lock a
> cache line or "possibly" lock the bus for SMR i686 impl.

"Should" and "possibly" aside, which one is faster and by what margin? ;-)

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