libnvdimm: Add sysfs numa_node to NVDIMM devices

Add support of sysfs 'numa_node' to I/O-related NVDIMM devices
under /sys/bus/nd/devices, regionN, namespaceN.0, and bttN.x.

An example of numa_node values on a 2-socket system with a single
NVDIMM range on each socket is shown below.
  /sys/bus/nd/devices
  |-- btt0.0/numa_node:0
  |-- btt1.0/numa_node:1
  |-- btt1.1/numa_node:1
  |-- namespace0.0/numa_node:0
  |-- namespace1.0/numa_node:1
  |-- region0/numa_node:0
  |-- region1/numa_node:1

These numa_node files are then linked under the block class of
their device names.
  /sys/class/block/pmem0/device/numa_node:0
  /sys/class/block/pmem1s/device/numa_node:1

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/pmem1s --show

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/drivers/acpi/nfit.c b/drivers/acpi/nfit.c
index d96c8fe..2161fa1 100644 (file)
--- a/drivers/acpi/nfit.c
+++ b/drivers/acpi/nfit.c
@@ -873,6 +873,7 @@ static const struct attribute_group *acpi_nfit_region_attribute_groups[] = {
        &nd_region_attribute_group,
        &nd_mapping_attribute_group,
        &nd_device_attribute_group,
+       &nd_numa_attribute_group,
        &acpi_nfit_region_attribute_group,
        NULL,
 };

diff --git a/drivers/nvdimm/btt_devs.c b/drivers/nvdimm/btt_devs.c
index 661aace..6ac8c0f 100644 (file)
--- a/drivers/nvdimm/btt_devs.c
+++ b/drivers/nvdimm/btt_devs.c
@@ -293,6 +293,7 @@ static struct attribute_group nd_btt_attribute_group = {
 static const struct attribute_group *nd_btt_attribute_groups[] = {
        &nd_btt_attribute_group,
        &nd_device_attribute_group,
+       &nd_numa_attribute_group,
        NULL,
 };
 

diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c
index 2053446..8eb22c0 100644 (file)
--- a/drivers/nvdimm/bus.c
+++ b/drivers/nvdimm/bus.c
@@ -280,6 +280,36 @@ struct attribute_group nd_device_attribute_group = {
 };
 EXPORT_SYMBOL_GPL(nd_device_attribute_group);
 
+static ssize_t numa_node_show(struct device *dev,
+               struct device_attribute *attr, char *buf)
+{
+       return sprintf(buf, "%d\n", dev_to_node(dev));
+}
+static DEVICE_ATTR_RO(numa_node);
+
+static struct attribute *nd_numa_attributes[] = {
+       &dev_attr_numa_node.attr,
+       NULL,
+};
+
+static umode_t nd_numa_attr_visible(struct kobject *kobj, struct attribute *a,
+               int n)
+{
+       if (!IS_ENABLED(CONFIG_NUMA))
+               return 0;
+
+       return a->mode;
+}
+
+/**
+ * nd_numa_attribute_group - NUMA attributes for all devices on an nd bus
+ */
+struct attribute_group nd_numa_attribute_group = {
+       .attrs = nd_numa_attributes,
+       .is_visible = nd_numa_attr_visible,
+};
+EXPORT_SYMBOL_GPL(nd_numa_attribute_group);
+
 int nvdimm_bus_create_ndctl(struct nvdimm_bus *nvdimm_bus)
 {
        dev_t devt = MKDEV(nvdimm_bus_major, nvdimm_bus->id);

diff --git a/drivers/nvdimm/namespace_devs.c b/drivers/nvdimm/namespace_devs.c
index 27d69bd..fef0dd8 100644 (file)
--- a/drivers/nvdimm/namespace_devs.c
+++ b/drivers/nvdimm/namespace_devs.c
@@ -1228,6 +1228,7 @@ static struct attribute_group nd_namespace_attribute_group = {
 static const struct attribute_group *nd_namespace_attribute_groups[] = {
        &nd_device_attribute_group,
        &nd_namespace_attribute_group,
+       &nd_numa_attribute_group,
        NULL,
 };
 

diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h
index 30b3dea..75e3af0 100644 (file)
--- a/include/linux/libnvdimm.h
+++ b/include/linux/libnvdimm.h
@@ -38,6 +38,7 @@ enum {
 extern struct attribute_group nvdimm_bus_attribute_group;
 extern struct attribute_group nvdimm_attribute_group;
 extern struct attribute_group nd_device_attribute_group;
+extern struct attribute_group nd_numa_attribute_group;
 extern struct attribute_group nd_region_attribute_group;
 extern struct attribute_group nd_mapping_attribute_group;