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authorDan Williams <dan.j.williams@intel.com>2019-11-17 09:45:45 -0800
committerDan Williams <dan.j.williams@intel.com>2019-11-19 09:52:41 -0800
commitbcba0c45471269d98cdbf53830694acf5a9792fc (patch)
tree35075a8e1bdbfebe944c47e1235c5c1b19529c57 /drivers/nvdimm
parentcb4dd729ee6ccc67ad604b1750990eb8c18783fa (diff)
downloadlinux-bcba0c45471269d98cdbf53830694acf5a9792fc.tar.bz2
libnvdimm: Export the target_node attribute for regions and namespaces
Aneesh points out that some platforms may have "local" attached persistent memory and "remote" persistent memory that map to the same "online" node, or persistent memory devices with different performance properties. In this case 'numa_node' is identical for the two instances, but 'target_node' is differentiated so platform firmware can communicate distinct performance properties per range. Expose 'target_node' by default to allow for disambiguation of devices that share the same numa_map_to_online_node() result. Reported-by: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Link: https://lore.kernel.org/r/157401274500.43284.2369509941678577768.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/nvdimm')
-rw-r--r--drivers/nvdimm/bus.c29
1 files changed, 29 insertions, 0 deletions
diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c
index 1d330d46d036..f76d709426f7 100644
--- a/drivers/nvdimm/bus.c
+++ b/drivers/nvdimm/bus.c
@@ -685,17 +685,46 @@ static ssize_t numa_node_show(struct device *dev,
}
static DEVICE_ATTR_RO(numa_node);
+static int nvdimm_dev_to_target_node(struct device *dev)
+{
+ struct device *parent = dev->parent;
+ struct nd_region *nd_region = NULL;
+
+ if (is_nd_region(dev))
+ nd_region = to_nd_region(dev);
+ else if (parent && is_nd_region(parent))
+ nd_region = to_nd_region(parent);
+
+ if (!nd_region)
+ return NUMA_NO_NODE;
+ return nd_region->target_node;
+}
+
+static ssize_t target_node_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return sprintf(buf, "%d\n", nvdimm_dev_to_target_node(dev));
+}
+static DEVICE_ATTR_RO(target_node);
+
static struct attribute *nd_numa_attributes[] = {
&dev_attr_numa_node.attr,
+ &dev_attr_target_node.attr,
NULL,
};
static umode_t nd_numa_attr_visible(struct kobject *kobj, struct attribute *a,
int n)
{
+ struct device *dev = container_of(kobj, typeof(*dev), kobj);
+
if (!IS_ENABLED(CONFIG_NUMA))
return 0;
+ if (a == &dev_attr_target_node.attr &&
+ nvdimm_dev_to_target_node(dev) == NUMA_NO_NODE)
+ return 0;
+
return a->mode;
}