Dan Williams <dan.j.williams@xxxxxxxxx> writes:
> 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.
So, am I correct in deducing that your primary motivation is testing
without hardware/firmware support? This looks like a bit of a hack to
me, and I think maybe it would be better to just emulate the HMAT using
qemu. I don't have a strong objection, though.
-Jeff
>
> All review welcome of course, but the E820 changes want an x86
> maintainer ack, the efi_fake_mem update needs Ard, and Rafael has
> previously shepherded the HMAT changes. For the changes to
> kernel/resource.c, where there is no clear maintainer, I just copied the
> last few people to make thoughtful changes in that area. I am happy to
> take these through the nvdimm tree along with these prerequisites
> already in -next:
>
> 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 (5):
> ACPI: 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/x86/kernel/e820.c | 16 +++++-
> arch/x86/mm/numa.c | 4 +
> drivers/acpi/numa/hmat.c | 71 +++-----------------------
> 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 | 1
> include/linux/dax.h | 8 +++
> kernel/resource.c | 1
> 12 files changed, 156 insertions(+), 70 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
