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

Message

Rob Herring Dec. 16, 2021, 11:31 p.m. UTC

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/[e-mail]/

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(-)

Comments

Greg Kroah-Hartman Dec. 21, 2021, 9:31 a.m. UTC | #1

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/[e-mail]/
> 
> 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 <[e-mail]>