Re: [PATCH -next] tile: set ARCH_KMALLOC_MINALIGN

[Chris Metcalf <cmetcalf@tilera.com>]

On 6/29/2010 10:10 PM, FUJITA Tomonori wrote:
> Ok, here's the second version.
>
> Can I assume that you'll merge the patch into your git tree on
> kernel.org?
>   

Sure, I'll take this patch into my arch/tile tree on kernel.org.  I
already took (a superset of) the one removing L1_CACHE_ALIGN as well. 
Thanks.

> =
> From: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
> Subject: [PATCH] tile: set ARCH_KMALLOC_MINALIGN
>
> Architectures that handle DMA-non-coherent memory need to set
> ARCH_KMALLOC_MINALIGN to make sure that kmalloc'ed buffer is DMA-safe:
> the buffer doesn't share a cache with the others.
>
> Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
> ---
>  arch/tile/include/asm/cache.h |    8 ++++++++
>  1 files changed, 8 insertions(+), 0 deletions(-)
>
> diff --git a/arch/tile/include/asm/cache.h b/arch/tile/include/asm/cache.h
> index ee59714..869a14f 100644
> --- a/arch/tile/include/asm/cache.h
> +++ b/arch/tile/include/asm/cache.h
> @@ -31,6 +31,14 @@
>  #define L2_CACHE_BYTES		(1 << L2_CACHE_SHIFT)
>  #define L2_CACHE_ALIGN(x)	(((x)+(L2_CACHE_BYTES-1)) & -L2_CACHE_BYTES)
>  
> +/*
> + * TILE-Gx is fully coherents so we don't need to define
> + * ARCH_KMALLOC_MINALIGN.
> + */
> +#ifndef __tilegx__
> +#define ARCH_KMALLOC_MINALIGN	L2_CACHE_BYTES
> +#endif
> +
>  /* use the cache line size for the L2, which is where it counts */
>  #define SMP_CACHE_BYTES_SHIFT	L2_CACHE_SHIFT
>  #define SMP_CACHE_BYTES		L2_CACHE_BYTES
>   

-- 
Chris Metcalf, Tilera Corp.
http://www.tilera.com