Persistent memory, as described by the ACPI NFIT (NVDIMM Firmware Interface Table), is the first known instance of a memory range described by a unique "target" proximity domain. Where "initiator" and "target" proximity domains is an approach that the ACPI HMAT (Heterogeneous Memory Attributes Table) uses to described the unique performance properties of a memory range relative to a given initiator (e.g. CPU or DMA device).
Currently the numa-node for a /dev/pmemX block-device or /dev/daxX.Y char-device follows the traditional notion of 'numa-node' where the attribute conveys the closest online numa-node. That numa-node attribute is useful for cpu-binding and memory-binding processes *near* the device. However, when the memory range backing a 'pmem', or 'dax' device is onlined (memory hot-add) the memory-only-numa-node representing that address needs to be differentiated from the set of online nodes. In other words, the numa-node association of the device depends on whether you can bind processes *near* the cpu-numa-node in the offline device-case, or bind process *on* the memory-range directly after the backing address range is onlined. Allow for the case that platform firmware describes persistent memory with a unique proximity domain, i.e. when it is distinct from the proximity of DRAM and CPUs that are on the same socket. Plumb the Linux numa-node translation of that proximity through the libnvdimm region device to namespaces that are in device-dax mode. With this in place the proposed kmem driver [1] can optionally discover a unique numa-node number for the address range as it transitions the memory from an offline state managed by a device-driver to an online memory range managed by the core-mm. [1]: https://lkml.org/lkml/2018/10/23/9 Reported-by: Fan Du <fan...@intel.com> Cc: Michael Ellerman <m...@ellerman.id.au> Cc: "Oliver O'Halloran" <ooh...@gmail.com> Cc: Dave Hansen <dave.han...@linux.intel.com> Cc: Jérôme Glisse <jgli...@redhat.com> Signed-off-by: Dan Williams <dan.j.willi...@intel.com> --- arch/powerpc/platforms/pseries/papr_scm.c | 1 + drivers/acpi/nfit/core.c | 8 ++++++-- drivers/acpi/numa.c | 1 + drivers/dax/bus.c | 4 +++- drivers/dax/bus.h | 3 ++- drivers/dax/dax-private.h | 4 ++++ drivers/dax/pmem/core.c | 4 +++- drivers/nvdimm/e820.c | 1 + drivers/nvdimm/nd.h | 2 +- drivers/nvdimm/of_pmem.c | 1 + drivers/nvdimm/region_devs.c | 1 + include/linux/libnvdimm.h | 1 + 12 files changed, 25 insertions(+), 6 deletions(-) diff --git a/arch/powerpc/platforms/pseries/papr_scm.c b/arch/powerpc/platforms/pseries/papr_scm.c index ee9372b65ca5..6a0a35b872d1 100644 --- a/arch/powerpc/platforms/pseries/papr_scm.c +++ b/arch/powerpc/platforms/pseries/papr_scm.c @@ -233,6 +233,7 @@ static int papr_scm_nvdimm_init(struct papr_scm_priv *p) memset(&ndr_desc, 0, sizeof(ndr_desc)); ndr_desc.attr_groups = region_attr_groups; ndr_desc.numa_node = dev_to_node(&p->pdev->dev); + ndr_desc.target_node = ndr_desc.numa_node; ndr_desc.res = &p->res; ndr_desc.of_node = p->dn; ndr_desc.provider_data = p; diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c index f8c638f3c946..2225e3de33ac 100644 --- a/drivers/acpi/nfit/core.c +++ b/drivers/acpi/nfit/core.c @@ -2825,11 +2825,15 @@ static int acpi_nfit_register_region(struct acpi_nfit_desc *acpi_desc, ndr_desc->res = &res; ndr_desc->provider_data = nfit_spa; ndr_desc->attr_groups = acpi_nfit_region_attribute_groups; - if (spa->flags & ACPI_NFIT_PROXIMITY_VALID) + if (spa->flags & ACPI_NFIT_PROXIMITY_VALID) { ndr_desc->numa_node = acpi_map_pxm_to_online_node( spa->proximity_domain); - else + ndr_desc->target_node = acpi_map_pxm_to_node( + spa->proximity_domain); + } else { ndr_desc->numa_node = NUMA_NO_NODE; + ndr_desc->target_node = NUMA_NO_NODE; + } /* * Persistence domain bits are hierarchical, if diff --git a/drivers/acpi/numa.c b/drivers/acpi/numa.c index 274699463b4f..b9d86babb13a 100644 --- a/drivers/acpi/numa.c +++ b/drivers/acpi/numa.c @@ -84,6 +84,7 @@ int acpi_map_pxm_to_node(int pxm) return node; } +EXPORT_SYMBOL(acpi_map_pxm_to_node); /** * acpi_map_pxm_to_online_node - Map proximity ID to online node diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index 568168500217..c620ad52d7e5 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -214,7 +214,7 @@ static void dax_region_unregister(void *region) } struct dax_region *alloc_dax_region(struct device *parent, int region_id, - struct resource *res, unsigned int align, + struct resource *res, int target_node, unsigned int align, unsigned long pfn_flags) { struct dax_region *dax_region; @@ -244,6 +244,7 @@ struct dax_region *alloc_dax_region(struct device *parent, int region_id, dax_region->id = region_id; dax_region->align = align; dax_region->dev = parent; + dax_region->target_node = target_node; if (sysfs_create_groups(&parent->kobj, dax_region_attribute_groups)) { kfree(dax_region); return NULL; @@ -348,6 +349,7 @@ struct dev_dax *__devm_create_dev_dax(struct dax_region *dax_region, int id, dev_dax->dax_dev = dax_dev; dev_dax->region = dax_region; + dev_dax->target_node = dax_region->target_node; kref_get(&dax_region->kref); inode = dax_inode(dax_dev); diff --git a/drivers/dax/bus.h b/drivers/dax/bus.h index ce977552ffb5..8619e3299943 100644 --- a/drivers/dax/bus.h +++ b/drivers/dax/bus.h @@ -10,7 +10,8 @@ struct dax_device; struct dax_region; void dax_region_put(struct dax_region *dax_region); struct dax_region *alloc_dax_region(struct device *parent, int region_id, - struct resource *res, unsigned int align, unsigned long flags); + struct resource *res, int target_node, unsigned int align, + unsigned long flags); enum dev_dax_subsys { DEV_DAX_BUS, diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h index a82ce48f5884..a45612148ca0 100644 --- a/drivers/dax/dax-private.h +++ b/drivers/dax/dax-private.h @@ -26,6 +26,7 @@ void dax_bus_exit(void); /** * struct dax_region - mapping infrastructure for dax devices * @id: kernel-wide unique region for a memory range + * @target_node: effective numa node if this memory range is onlined * @kref: to pin while other agents have a need to do lookups * @dev: parent device backing this region * @align: allocation and mapping alignment for child dax devices @@ -34,6 +35,7 @@ void dax_bus_exit(void); */ struct dax_region { int id; + int target_node; struct kref kref; struct device *dev; unsigned int align; @@ -46,6 +48,7 @@ struct dax_region { * data while the device is activated in the driver. * @region - parent region * @dax_dev - core dax functionality + * @target_node: effective numa node if dev_dax memory range is onlined * @dev - device core * @pgmap - pgmap for memmap setup / lifetime (driver owned) * @ref: pgmap reference count (driver owned) @@ -54,6 +57,7 @@ struct dax_region { struct dev_dax { struct dax_region *region; struct dax_device *dax_dev; + int target_node; struct device dev; struct dev_pagemap pgmap; struct percpu_ref ref; diff --git a/drivers/dax/pmem/core.c b/drivers/dax/pmem/core.c index bdcff1b14e95..f71019ce0647 100644 --- a/drivers/dax/pmem/core.c +++ b/drivers/dax/pmem/core.c @@ -20,6 +20,7 @@ struct dev_dax *__dax_pmem_probe(struct device *dev, enum dev_dax_subsys subsys) struct nd_namespace_common *ndns; struct nd_dax *nd_dax = to_nd_dax(dev); struct nd_pfn *nd_pfn = &nd_dax->nd_pfn; + struct nd_region *nd_region = to_nd_region(dev->parent); ndns = nvdimm_namespace_common_probe(dev); if (IS_ERR(ndns)) @@ -52,7 +53,8 @@ struct dev_dax *__dax_pmem_probe(struct device *dev, enum dev_dax_subsys subsys) memcpy(&res, &pgmap.res, sizeof(res)); res.start += offset; dax_region = alloc_dax_region(dev, region_id, &res, - le32_to_cpu(pfn_sb->align), PFN_DEV|PFN_MAP); + nd_region->target_node, le32_to_cpu(pfn_sb->align), + PFN_DEV|PFN_MAP); if (!dax_region) return ERR_PTR(-ENOMEM); diff --git a/drivers/nvdimm/e820.c b/drivers/nvdimm/e820.c index 521eaf53a52a..36be9b619187 100644 --- a/drivers/nvdimm/e820.c +++ b/drivers/nvdimm/e820.c @@ -47,6 +47,7 @@ static int e820_register_one(struct resource *res, void *data) ndr_desc.res = res; ndr_desc.attr_groups = e820_pmem_region_attribute_groups; ndr_desc.numa_node = e820_range_to_nid(res->start); + ndr_desc.target_node = ndr_desc.numa_node; set_bit(ND_REGION_PAGEMAP, &ndr_desc.flags); if (!nvdimm_pmem_region_create(nvdimm_bus, &ndr_desc)) return -ENXIO; diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h index e79cc8e5c114..623216545cc8 100644 --- a/drivers/nvdimm/nd.h +++ b/drivers/nvdimm/nd.h @@ -153,7 +153,7 @@ struct nd_region { u16 ndr_mappings; u64 ndr_size; u64 ndr_start; - int id, num_lanes, ro, numa_node; + int id, num_lanes, ro, numa_node, target_node; void *provider_data; struct kernfs_node *bb_state; struct badblocks bb; diff --git a/drivers/nvdimm/of_pmem.c b/drivers/nvdimm/of_pmem.c index 0a701837dfc0..ecaaa27438e2 100644 --- a/drivers/nvdimm/of_pmem.c +++ b/drivers/nvdimm/of_pmem.c @@ -68,6 +68,7 @@ static int of_pmem_region_probe(struct platform_device *pdev) memset(&ndr_desc, 0, sizeof(ndr_desc)); ndr_desc.attr_groups = region_attr_groups; ndr_desc.numa_node = dev_to_node(&pdev->dev); + ndr_desc.target_node = ndr_desc.numa_node; ndr_desc.res = &pdev->resource[i]; ndr_desc.of_node = np; set_bit(ND_REGION_PAGEMAP, &ndr_desc.flags); diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c index 174a418cb171..86cd425b786d 100644 --- a/drivers/nvdimm/region_devs.c +++ b/drivers/nvdimm/region_devs.c @@ -1060,6 +1060,7 @@ static struct nd_region *nd_region_create(struct nvdimm_bus *nvdimm_bus, nd_region->flags = ndr_desc->flags; nd_region->ro = ro; nd_region->numa_node = ndr_desc->numa_node; + nd_region->target_node = ndr_desc->target_node; ida_init(&nd_region->ns_ida); ida_init(&nd_region->btt_ida); ida_init(&nd_region->pfn_ida); diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h index 097072c5a852..941102c0c81f 100644 --- a/include/linux/libnvdimm.h +++ b/include/linux/libnvdimm.h @@ -124,6 +124,7 @@ struct nd_region_desc { void *provider_data; int num_lanes; int numa_node; + int target_node; unsigned long flags; struct device_node *of_node; }; _______________________________________________ Linux-nvdimm mailing list Linux-nvdimm@lists.01.org https://lists.01.org/mailman/listinfo/linux-nvdimm
