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SubjectRe: [PATCH 01/01][retry 5] x86: L3 cache index disable for 2.6.26
On Thu, Aug 14, 2008 at 11:48:37AM -0500, Mark Langsdorf wrote:
> New versions of AMD processors have support to disable parts
> of their L3 caches if too many MCEs are generated by the
> L3 cache.  
>
> This patch provides a /sysfs interface under the cache
> hierarchy to display which caches indices are disabled
> (if any) and to monitoring applications to disable a
> cache index.
>
> This patch does not set an automatic policy to disable
> the L3 cache.  Policy decisions would need to be made
> by a RAS handler.  This patch merely makes it easier to
> see what indices are currently disabled.
>
> Signed-off-by: Mark Langsdorf <mark.langsdorf@amd.com>
>
> diff -r e683983d4dd0 Documentation/ABI/testing/sysfs-devices-cache_disable
> --- /dev/null Thu Jan 01 00:00:00 1970 +0000
> +++ b/Documentation/ABI/testing/sysfs-devices-cache_disable Thu Aug 14 03:49:19 2008 -0500
> @@ -0,0 +1,18 @@
> +What: /sys/devices/system/cpu/cpu*/cache/index*/cache_disable_X
> +Date: August 2008
> +KernelVersion: 2.6.27
> +Contact: mark.langsdorf@amd.com
> +Description: These files exist in every cpu's cache index directories.
> + There are currently 2 cache_disable_# files in each
> + directory. Reading from these files on a supported
> + processor will return that cache disable index value
> + for that processor and node. Writing to one of these
> + files will cause the specificed cache index to be disabled.
> +
> + Currently, only AMD Family 10h Processors support cache index
> + disable, and only for their L3 caches. See the BIOS and
> + Kernel Developer's Guide at
> + http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/31116.PDF
> + for formatting information and other details on the
> + cache index disable.
> +Users: joachim.deguara@amd.com
> diff -r e683983d4dd0 arch/x86/kernel/cpu/intel_cacheinfo.c
> --- a/arch/x86/kernel/cpu/intel_cacheinfo.c Tue Aug 12 08:46:38 2008 -0500
> +++ b/arch/x86/kernel/cpu/intel_cacheinfo.c Thu Aug 14 06:23:13 2008 -0500
> @@ -16,6 +16,9 @@
>
> #include <asm/processor.h>
> #include <asm/smp.h>
> +
> +#include <linux/pci.h>
> +#include <asm/k8.h>
>
> #define LVL_1_INST 1
> #define LVL_1_DATA 2
> @@ -130,6 +133,7 @@ struct _cpuid4_info {
> union _cpuid4_leaf_ebx ebx;
> union _cpuid4_leaf_ecx ecx;
> unsigned long size;
> + unsigned long can_disable;

Why use an unsigned long for a single bit value? bool perhaps?

thanks,

greg k-h
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