Changes since v1 [1]: - Kill the ifdef'ery in arch/x86/mm/numa.c (Rafael) - Add a dummy phys_to_target_node() for ARM64 (0day-robot) - Initialize ->child and ->sibling to NULL in the resource returned by find_next_iomem_res() (Inspired by Tom's feedback even though it does not set them like he suggested) - Collect Ard's Ack [1]: http://lore.kernel.org/r/158318759687.2216124.4684754859068906007.stgit@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx --- My primary motivation is making the dax_kmem facility useful to shipping platforms that have performance differentiated memory, but may not have EFI-defined soft-reservations / HMAT (or non-EFI-ACPI-platform equivalent). I'm anticipating HMAT enabled platforms where the platform firmware policy for what is soft-reserved, or not, is not the policy the system owner would pick. I'd also highlight Joao's work [2] (see the TODO section) as an indication of the demand for custom carving memory resources and applying the device-dax memory management interface. Given the current dearth of systems that supply an ACPI HMAT table, and the utility of being able to manually define device-dax "hmem" instances via the efi_fake_mem= option, relax the requirements for creating these devices. Specifically, add an option (numa=nohmat) to optionally disable consideration of the HMAT and update efi_fake_mem= to behave like memmap=nn!ss in terms of delimiting device boundaries. [2]: https://lore.kernel.org/lkml/20200110190313.17144-1-joao.m.martins@xxxxxxxxxx/ With Ard's and Rafael's ack I'd feel ok taking this through the nvdimm tree, please holler if anything still needs some fixups. Dependencies: b2ca916ce392 ACPI: NUMA: Up-level "map to online node" functionality 4fcbe96e4d0b mm/numa: Skip NUMA_NO_NODE and online nodes in numa_map_to_online_node() 575e23b6e13c powerpc/papr_scm: Switch to numa_map_to_online_node() 1e5d8e1e47af x86/mm: Introduce CONFIG_NUMA_KEEP_MEMINFO 5d30f92e7631 x86/NUMA: Provide a range-to-target_node lookup facility 7b27a8622f80 libnvdimm/e820: Retrieve and populate correct 'target_node' info Tested with: numa=nohmat efi_fake_mem=4G@9G:0x40000,4G@13G:0x40000 ...to create to device-dax instances: # daxctl list -RDu [ { "path":"\/platform\/hmem.1", "id":1, "size":"4.00 GiB (4.29 GB)", "align":2097152, "devices":[ { "chardev":"dax1.0", "size":"4.00 GiB (4.29 GB)", "target_node":3, "mode":"devdax" } ] }, { "path":"\/platform\/hmem.0", "id":0, "size":"4.00 GiB (4.29 GB)", "align":2097152, "devices":[ { "chardev":"dax0.0", "size":"4.00 GiB (4.29 GB)", "target_node":2, "mode":"devdax" } ] } ] --- Dan Williams (6): x86/numa: Cleanup configuration dependent command-line options x86/numa: Add 'nohmat' option efi/fake_mem: Arrange for a resource entry per efi_fake_mem instance ACPI: HMAT: Refactor hmat_register_target_device to hmem_register_device resource: Report parent to walk_iomem_res_desc() callback ACPI: HMAT: Attach a device for each soft-reserved range arch/arm64/mm/numa.c | 13 +++++ arch/x86/include/asm/numa.h | 8 +++ arch/x86/kernel/e820.c | 16 +++++- arch/x86/mm/numa.c | 10 +--- arch/x86/mm/numa_emulation.c | 3 + arch/x86/xen/enlighten_pv.c | 2 - drivers/acpi/numa/hmat.c | 76 +++++---------------------- drivers/acpi/numa/srat.c | 9 +++ drivers/dax/Kconfig | 5 ++ drivers/dax/Makefile | 3 - drivers/dax/hmem/Makefile | 6 ++ drivers/dax/hmem/device.c | 97 +++++++++++++++++++++++++++++++++++ drivers/dax/hmem/hmem.c | 2 - drivers/firmware/efi/x86_fake_mem.c | 12 +++- include/acpi/acpi_numa.h | 14 +++++ include/linux/dax.h | 8 +++ kernel/resource.c | 11 +++- 17 files changed, 209 insertions(+), 86 deletions(-) create mode 100644 drivers/dax/hmem/Makefile create mode 100644 drivers/dax/hmem/device.c rename drivers/dax/{hmem.c => hmem/hmem.c} (98%) base-commit: 7b27a8622f802761d5c6abd6c37b22312a35343c
