Re: [PATCH] mutex: Introduce mutex_cpu_relax()

Peter Zijlstra
2010-10-14T15:59:35Z

On Thu, 2010-10-14 at 17:33 +0200, Gerald Schaefer wrote:

> --- a/arch/s390/Kconfig
> +++ b/arch/s390/Kconfig
> @@ -100,6 +100,7 @@ config S390
> select HAVE_KERNEL_BZIP2
> select HAVE_KERNEL_LZMA
> select HAVE_KERNEL_LZO
> + select HAVE_MUTEX_CPU_RELAX
> select ARCH_INLINE_SPIN_TRYLOCK
> select ARCH_INLINE_SPIN_TRYLOCK_BH
> select ARCH_INLINE_SPIN_LOCK

>
> +#ifndef HAVE_MUTEX_CPU_RELAX
> +#define mutex_cpu_relax() cpu_relax()
> +#endif

Won't KConfig make CONFIG_HAVE_MUTEX_CPU_RELAX from that?

Also, don't you have to first create a dummy Kconfig variable before you
select it?