[PATCH v3 0/3] Add NUMA support for NVDIMM devices

Toshi Kani
2015-06-19T18:18:31Z

Since NVDIMMs are installed on memory slots, they expose the NUMA
topology of a platform. This patchset adds support of sysfs
'numa_node' to I/O-related NVDIMM devices under /sys/bus/nd/devices.
This enables numactl(8) to accept 'block:' and 'file:' paths of pmem
and btt devices as shown in the examples below.
numactl --preferred block:pmem0 --show
numactl --preferred file:/dev/pmem0s --show

numactl can be used to bind an application to the locality of a target
NVDIMM for better performance. A result of fio benchmark to ext4/dax
on an HP DL380 with 2 sockets for local & remote settings is shown
below.

Local [1] : 4098.3MB/s
Remote [2]: 3718.4MB/s

[1] numactl --preferred block:pmem0 --cpunodebind block:pmem0 fio <fs-on-pmem0>
[2] numactl --preferred block:pmem1 --cpunodebind block:pmem1 fio <fs-on-pmem0>

Patch 1/3 applies on top of the acpica branch of the pm tree.
Patch 2/3-3/3 apply on top of Dan Williams's patch series
"libnvdimm: ->rw_bytes(), BLK-mode, unit tests, and misc features".

---
v3:
- Update the comment of acpi_map_pxm_to_online_node(). (Rafael Wysocki)

v2:
- Add acpi_map_pxm_to_online_node(), which returns an online node.
- Manage visibility of sysfs numa_node with is_visible. (Dan Williams)
- Check ACPI_NFIT_PROXIMITY_VALID in spa->flags.

---
Toshi Kani (3):
1/3 acpi: Add acpi_map_pxm_to_online_node()
2/3 libnvdimm: Set numa_node to NVDIMM devices
3/3 libnvdimm: Add sysfs numa_node to NVDIMM devices

---
drivers/acpi/nfit.c | 7 ++++++
drivers/acpi/numa.c | 50 ++++++++++++++++++++++++++++++++++++++---
drivers/nvdimm/btt.c | 2 ++
drivers/nvdimm/btt_devs.c | 1 +
drivers/nvdimm/bus.c | 30 +++++++++++++++++++++++++
drivers/nvdimm/namespace_devs.c | 1 +
drivers/nvdimm/nd.h | 1 +
drivers/nvdimm/region.c | 1 +
drivers/nvdimm/region_devs.c | 1 +
include/linux/acpi.h | 5 +++++
include/linux/libnvdimm.h | 2 ++
11 files changed, 98 insertions(+), 3 deletions(-)