Re: [PATCH] Define __raw_get_cpu_var and use it

[David S. Miller]

From: Paul Mackerras <paulus@xxxxxxxxx>
Date: Wed, 10 May 2006 13:30:13 +1000

> 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>

Thank you:

Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
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