Re: [-mm patch] {rd,wr}msr_on_cpu SMP=n optimization

[Alexey Dobriyan <adobriyan@openvz.org>]

On Mon, Feb 19, 2007 at 07:14:34PM -0500, Dave Jones wrote:
> On Tue, Feb 20, 2007 at 01:07:13AM +0100, Adrian Bunk wrote:
>  > On Thu, Feb 15, 2007 at 05:14:08AM -0800, Andrew Morton wrote:
>  > >...
>  > > Changes since 2.6.20-rc6-mm3:
>  > >...
>  > > +rdmsr_on_cpu-wrmsr_on_cpu.patch
>  > >...
>  > >  x86 updates
>  > >...
>  >
>  > Let's save a few bytes in the CONFIG_SMP=n case.
>  >
>  > Signed-off-by: Adrian Bunk <bunk@stusta.de>
>  >
>  > ---
>  >
>  > BTW: currently -ENOUSERS
>
> There was a follow-on patch that converted p4-clockmod to use it for one.

And patch for powernow-k8 in preparations.

>  > +#ifdef CONFIG_SMP
>  >  void rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h);
>  >  void wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h);
>  > +#else  /*  CONFIG_SMP  */
>  > +static inline void rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
>  > +{
>  > +	rdmsr(msr_no, *l, *h);
>  > +}
>  > +static inline void wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
>  > +{
>  > +	wrmsr(msr_no, l, h);
>  > +}
>  > +#endif  /*  CONFIG_SMP  */
>
> BUG_ON(cpu!=smp_processor_id()) maybe?

This make sense. Fell free to add it.

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