[PATCH v3 0/8] Add support for FORM2 associativity

[Aneesh Kumar K.V]

Form2 associativity adds a much more flexible NUMA topology layout
than what is provided by Form1. This also allows PAPR SCM device
to use better associativity when using the device as DAX KMEM
device. More details can be found in patch 7.

$ ndctl list -N -v
[
  {
    "dev":"namespace0.0",
    "mode":"devdax",
    "map":"dev",
    "size":1071644672,
    "uuid":"37dea198-ddb5-4e42-915a-99a915e24188",
    "raw_uuid":"148deeaa-4a2f-41d1-8d74-fd9a942d26ba",
    "daxregion":{
      "id":0,
      "size":1071644672,
      "devices":[
        {
          "chardev":"dax0.0",
          "size":1071644672,
          "target_node":4,
          "mode":"devdax"
        }
      ]
    },
    "align":2097152,
    "numa_node":1
  }
]

$ numactl -H
...
node distances:
node   0   1   2   3 
  0:  10  11  222  33 
  1:  44  10  55  66 
  2:  77  88  10  99 
  3:  101  121  132  10 
$

After DAX KMEM
# numactl -H
available: 5 nodes (0-4)
...
node distances:
node   0   1   2   3   4 
  0:  10  11  22  33  255 
  1:  44  10  55  66  255 
  2:  77  88  10  99  255 
  3:  101  121  132  10  255 
  4:  255  255  255  255  10 
# 

The above output is with a Qemu command line

-numa node,nodeid=4 \
-numa dist,src=0,dst=1,val=11 -numa dist,src=0,dst=2,val=22 -numa dist,src=0,dst=3,val=33 -numa dist,src=0,dst=4,val=255 \
-numa dist,src=1,dst=0,val=44 -numa dist,src=1,dst=2,val=55 -numa dist,src=1,dst=3,val=66 -numa dist,src=1,dst=4,val=255 \
-numa dist,src=2,dst=0,val=77 -numa dist,src=2,dst=1,val=88 -numa dist,src=2,dst=3,val=99 -numa dist,src=2,dst=4,val=255 \
-numa dist,src=3,dst=0,val=101 -numa dist,src=3,dst=1,val=121 -numa dist,src=3,dst=2,val=132 -numa dist,src=3,dst=4,val=255 \
-numa dist,src=4,dst=0,val=255 -numa dist,src=4,dst=1,val=255 -numa dist,src=4,dst=2,val=255 -numa dist,src=4,dst=3,val=255 \
-object memory-backend-file,id=memnvdimm1,prealloc=yes,mem-path=$PMEM_DISK,share=yes,size=${PMEM_SIZE}  \
-device nvdimm,label-size=128K,memdev=memnvdimm1,id=nvdimm1,slot=4,uuid=72511b67-0b3b-42fd-8d1d-5be3cae8bcaa,node=4,device-node=1

Qemu changes can be found at https://lore.kernel.org/qemu-devel/20210616011944.2996399-1-danielhb413@gmail.com/

Changes from v2:
* Add nvdimm list to Cc:
* update PATCH 8 commit message.

Changes from v1:
* Update FORM2 documentation.
* rename max_domain_index to max_associativity_domain_index

Aneesh Kumar K.V (8):
  powerpc/pseries: rename min_common_depth to primary_domain_index
  powerpc/pseries: rename distance_ref_points_depth to
    max_associativity_domain_index
  powerpc/pseries: Rename TYPE1_AFFINITY to FORM1_AFFINITY
  powerpc/pseries: Consolidate DLPAR NUMA distance update
  powerpc/pseries: Consolidate NUMA distance update during boot
  powerpc/pseries: Add a helper for form1 cpu distance
  powerpc/pseries: Add support for FORM2 associativity
  powerpc/papr_scm: Use FORM2 associativity details

 Documentation/powerpc/associativity.rst       | 177 +++++++
 arch/powerpc/include/asm/firmware.h           |   7 +-
 arch/powerpc/include/asm/prom.h               |   3 +-
 arch/powerpc/kernel/prom_init.c               |   3 +-
 arch/powerpc/mm/numa.c                        | 436 ++++++++++++++----
 arch/powerpc/platforms/pseries/firmware.c     |   3 +-
 arch/powerpc/platforms/pseries/hotplug-cpu.c  |   2 +
 .../platforms/pseries/hotplug-memory.c        |   2 +
 arch/powerpc/platforms/pseries/papr_scm.c     |  26 +-
 arch/powerpc/platforms/pseries/pseries.h      |   2 +
 10 files changed, 560 insertions(+), 101 deletions(-)
 create mode 100644 Documentation/powerpc/associativity.rst

-- 
2.31.1