Re: [PATCH 1/3] MIPS: use the generic atomic64 operations for perf counter support

[David Daney <ddaney@caviumnetworks.com>]

On 04/15/2010 09:38 AM, Deng-Cheng Zhu wrote:
> Currently we take the generic spinlock'ed atomic64 implementation from the
> lib. The atomic64 types and related functions are needed for the Linux
> performance counter subsystem.
>
> Signed-off-by: Deng-Cheng Zhu<dengcheng.zhu@gmail.com>

NAK.

> ---
>   arch/mips/Kconfig              |    1 +
>   arch/mips/include/asm/atomic.h |    4 ++++
>   2 files changed, 5 insertions(+), 0 deletions(-)
>
> diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
> index 29e8692..7161751 100644
> --- a/arch/mips/Kconfig
> +++ b/arch/mips/Kconfig
> @@ -4,6 +4,7 @@ config MIPS
>   	select HAVE_GENERIC_DMA_COHERENT
>   	select HAVE_IDE
>   	select HAVE_OPROFILE
> +	select GENERIC_ATOMIC64
>   	select HAVE_ARCH_KGDB
>   	select HAVE_FUNCTION_TRACER
>   	select HAVE_FUNCTION_TRACE_MCOUNT_TEST
> diff --git a/arch/mips/include/asm/atomic.h b/arch/mips/include/asm/atomic.h
> index 519197e..b0a932e 100644
> --- a/arch/mips/include/asm/atomic.h
> +++ b/arch/mips/include/asm/atomic.h
> @@ -21,6 +21,10 @@
>   #include<asm/war.h>
>   #include<asm/system.h>
>
> +#ifdef CONFIG_GENERIC_ATOMIC64
> +#include<asm-generic/atomic64.h>
> +#endif
> +
>   #define ATOMIC_INIT(i)    { (i) }
>
>   /*

This is incorrect.  For 64-bit kernels, we already have all the 64-bit 
atomics implemented.  This will break 64-bit kernels.

David Daney