[PATCH 0/6] cacheinfo: CPU affinity and Devicetree 'id' support

Greg Kroah-Hartman gregkh at linuxfoundation.org
Tue Dec 21 01:31:22 PST 2021


On Thu, Dec 16, 2021 at 05:31:19PM -0600, Rob Herring wrote:
> For upcoming Arm MPAM support in resctrl, it is necessary to have the
> cacheinfo 'id' for MPAM enabled caches. The 'id' is part of the resctrl
> ABI. While this support already exists for ACPI based systems, it is
> missing for DT. This series adds the support.
> 
> The 'id' value used is the smallest CPU h/w id value associated with a
> cache. This requires walking the cache hierarchy from every CPU node to
> get all CPUs associated with a cache. As MPAM also needs to know this,
> the CPU affinity is also saved to avoid reimplementing and walking the
> firmware tables again.
> 
> Patches 1 and 2 are v2 from the prior series[1]. The rest are new.
> 
> Tested on arm64 with DT. ACPI changes are untested. I don't have a
> system with an appropriate PPTT nor do I know how to modify ACPI tables.
> 
> Rob
> 
> [1] https://lore.kernel.org/all/20211006164332.1981454-1-robh@kernel.org/
> 
> Rob Herring (6):
>   cacheinfo: Allow for >32-bit cache 'id'
>   cacheinfo: Set cache 'id' based on DT data
>   cacheinfo: Add cpu_affinity_map to store affinity for all CPUs
>   ACPI / PPTT: Populate the cacheinfo.cpu_affinity_map
>   cacheinfo: Use cpu_affinity_map for populating shared_cpu_map
>   cacheinfo: Add cacheinfo_get_cache_affinity() function
> 
>  drivers/acpi/pptt.c       | 29 +++++++++++++++--
>  drivers/base/cacheinfo.c  | 65 ++++++++++++++++++++++++++-------------
>  include/linux/cacheinfo.h | 29 +++++++++++++++--
>  3 files changed, 97 insertions(+), 26 deletions(-)
> 
> -- 
> 2.32.0
> 

Acked-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>



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