The patch titled
Subject: dax/kmem: use a single static memory group for a single probed unit
has been added to the -mm tree. Its filename is
dax-kmem-use-a-single-static-memory-group-for-a-single-probed-unit.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/dax-kmem-use-a-single-static-memory-group-for-a-single-probed-unit.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/dax-kmem-use-a-single-static-memory-group-for-a-single-probed-unit.patch
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------------------------------------------------------
From: David Hildenbrand <david@xxxxxxxxxx>
Subject: dax/kmem: use a single static memory group for a single probed unit
Although dax/kmem users often disable auto-onlining and instead online
memory manually (usually to ZONE_MOVABLE), there is still value in having
auto-onlining be aware of the relationship of memory blocks.
Let's treat one probed unit as a single static memory device, similar to a
single ACPI memory device.
Link: https://lkml.kernel.org/r/20210723125210.29987-7-david@xxxxxxxxxx
Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Hui Zhu <teawater@xxxxxxxxx>
Cc: Jason Wang <jasowang@xxxxxxxxxx>
Cc: Len Brown <lenb@xxxxxxxxxx>
Cc: Marek Kedzierski <mkedzier@xxxxxxxxxx>
Cc: "Michael S. Tsirkin" <mst@xxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Cc: Mike Rapoport <rppt@xxxxxxxxxx>
Cc: Oscar Salvador <osalvador@xxxxxxx>
Cc: Pankaj Gupta <pankaj.gupta.linux@xxxxxxxxx>
Cc: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>
Cc: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
Cc: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Wei Yang <richard.weiyang@xxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/dax/kmem.c | 40 ++++++++++++++++++++++++++++++++--------
1 file changed, 32 insertions(+), 8 deletions(-)
--- a/drivers/dax/kmem.c~dax-kmem-use-a-single-static-memory-group-for-a-single-probed-unit
+++ a/drivers/dax/kmem.c
@@ -37,15 +37,16 @@ static int dax_kmem_range(struct dev_dax
struct dax_kmem_data {
const char *res_name;
+ int mgid;
struct resource *res[];
};
static int dev_dax_kmem_probe(struct dev_dax *dev_dax)
{
struct device *dev = &dev_dax->dev;
+ unsigned long total_len = 0;
struct dax_kmem_data *data;
- int rc = -ENOMEM;
- int i, mapped = 0;
+ int i, rc, mapped = 0;
int numa_node;
/*
@@ -61,24 +62,44 @@ static int dev_dax_kmem_probe(struct dev
return -EINVAL;
}
+ for (i = 0; i < dev_dax->nr_range; i++) {
+ struct range range;
+
+ rc = dax_kmem_range(dev_dax, i, &range);
+ if (rc) {
+ dev_info(dev, "mapping%d: %#llx-%#llx too small after alignment\n",
+ i, range.start, range.end);
+ continue;
+ }
+ total_len += range_len(&range);
+ }
+
+ if (!total_len) {
+ dev_warn(dev, "rejecting DAX region without any memory after alignment\n");
+ return -EINVAL;
+ }
+
data = kzalloc(struct_size(data, res, dev_dax->nr_range), GFP_KERNEL);
if (!data)
return -ENOMEM;
+ rc = -ENOMEM;
data->res_name = kstrdup(dev_name(dev), GFP_KERNEL);
if (!data->res_name)
goto err_res_name;
+ rc = register_static_memory_group(numa_node, total_len);
+ if (rc < 0)
+ goto err_reg_mgid;
+ data->mgid = rc;
+
for (i = 0; i < dev_dax->nr_range; i++) {
struct resource *res;
struct range range;
rc = dax_kmem_range(dev_dax, i, &range);
- if (rc) {
- dev_info(dev, "mapping%d: %#llx-%#llx too small after alignment\n",
- i, range.start, range.end);
+ if (rc)
continue;
- }
/* Region is permanently reserved if hotremove fails. */
res = request_mem_region(range.start, range_len(&range), data->res_name);
@@ -108,8 +129,8 @@ static int dev_dax_kmem_probe(struct dev
* Ensure that future kexec'd kernels will not treat
* this as RAM automatically.
*/
- rc = add_memory_driver_managed(numa_node, range.start,
- range_len(&range), kmem_name, MHP_NONE);
+ rc = add_memory_driver_managed(data->mgid, range.start,
+ range_len(&range), kmem_name, MHP_NID_IS_MGID);
if (rc) {
dev_warn(dev, "mapping%d: %#llx-%#llx memory add failed\n",
@@ -129,6 +150,8 @@ static int dev_dax_kmem_probe(struct dev
return 0;
err_request_mem:
+ unregister_memory_group(data->mgid);
+err_reg_mgid:
kfree(data->res_name);
err_res_name:
kfree(data);
@@ -171,6 +194,7 @@ static void dev_dax_kmem_remove(struct d
}
if (success >= dev_dax->nr_range) {
+ unregister_memory_group(data->mgid);
kfree(data->res_name);
kfree(data);
dev_set_drvdata(dev, NULL);
_
Patches currently in -mm which might be from david@xxxxxxxxxx are
memory-hotplugrst-remove-locking-details-from-admin-guide.patch
memory-hotplugrst-complete-admin-guide-overhaul.patch
mm-memory_hotplug-use-unsigned-long-for-pfn-in-zone_for_pfn_range.patch
mm-memory_hotplug-remove-nid-parameter-from-arch_remove_memory.patch
mm-memory_hotplug-remove-nid-parameter-from-remove_memory-and-friends.patch
acpi-memhotplug-memory-resources-cannot-be-enabled-yet.patch
mm-track-present-early-pages-per-zone.patch
mm-memory_hotplug-introduce-auto-movable-online-policy.patch
drivers-base-memory-introduce-memory-groups-to-logically-group-memory-blocks.patch
mm-memory_hotplug-track-present-pages-in-memory-groups.patch
acpi-memhotplug-use-a-single-static-memory-group-for-a-single-memory-device.patch
dax-kmem-use-a-single-static-memory-group-for-a-single-probed-unit.patch
virtio-mem-use-a-single-dynamic-memory-group-for-a-single-virtio-mem-device.patch
mm-memory_hotplug-memory-group-aware-auto-movable-online-policy.patch
mm-memory_hotplug-improved-dynamic-memory-group-aware-auto-movable-online-policy.patch
