Re: [RFC 00/15] x86_64: Optimize percpu accesses

[Ingo Molnar <mingo@elte.hu>]

* Jeremy Fitzhardinge <jeremy@goop.org> wrote:

>> What is remaining is the task to rename
>>
>> 	pda.Y -> Z
>>
>> in order to make variable references the same under both arches. 
>> Presumably the Z is the corresponding 32 bit variable. There are 
>> likely a number of cases where the transformation is trivial if we 
>> just identify the corresponding 32 bit equivalent.
>
> Yes, I understand that, but it's still pointless churn.  The 
> intermediate step is no improvement over what was there before, and 
> isn't any closer to the desired final result.
>
> Once you've made the pda a percpu variable, and redefined all the 
> X_pda macros in terms of x86_X_percpu, then there's no need to touch 
> all the usage sites until you're *actually* going to unify something.  
> Touching them all just because you find "X_pda" unsightly doesn't help 
> anyone.  Ideally every site you touch will remove a #ifdef 
> CONFIG_X86_64, or make two as-yet unified pieces of code closer to 
> unification.

that makes sense. Does everyone agree on #1-#2-#3 and then gradual 
elimination of most pda members (without going through an intermediate 
renaming of pda members) being the way to go?

	Ingo