Re: [PATCH] Define __raw_get_cpu_var and use it

[Ingo Molnar]

* Paul Mackerras <paulus@xxxxxxxxx> wrote:

> There are several instances of per_cpu(foo, raw_smp_processor_id()), 
> which is semantically equivalent to __get_cpu_var(foo) but without the 
> warning that smp_processor_id() can give if CONFIG_DEBUG_PREEMPT is 
> enabled.  For those architectures with optimized per-cpu 
> implementations, namely ia64, powerpc, s390, sparc64 and x86_64, 
> per_cpu() turns into more and slower code than __get_cpu_var(), so it 
> would be preferable to use __get_cpu_var on those platforms.
> 
> This defines a __raw_get_cpu_var(x) macro which turns into per_cpu(x, 
> raw_smp_processor_id()) on architectures that use the generic per-cpu 
> implementation, and turns into __get_cpu_var(x) on the architectures 
> that have an optimized per-cpu implementation.
>     
> Signed-off-by: Paul Mackerras <paulus@xxxxxxxxx>

i made the original raw_smp_processor_id() changes and i never liked the 
per_cpu() open-coding it introduced. Your patch solves this problem 
nicely.

Acked-by: Ingo Molnar <mingo@xxxxxxx>

	Ingo
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