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cxl/region: Deal with numa nodes not enumerated by SRAT

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For the numa nodes that are not created by SRAT, no memory_target is
allocated and is not managed by the HMAT_REPORTING code. Therefore
hmat_callback() memory hotplug notifier will exit early on those NUMA
nodes. The CXL memory hotplug notifier will need to call
node_set_perf_attrs() directly in order to setup the access sysfs
attributes.

In acpi_numa_init(), the last proximity domain (pxm) id created by SRAT is
stored. Add a helper function acpi_node_backed_by_real_pxm() in order to
check if a NUMA node id is defined by SRAT or created by CFMWS.

node_set_perf_attrs() symbol is exported to allow update of perf attribs
for a node. The sysfs path of
/sys/devices/system/node/nodeX/access0/initiators/* is created by
node_set_perf_attrs() for the various attributes where nodeX is matched
to the NUMA node of the CXL region.

Cc: Rafael J. Wysocki <rafael@kernel.org>
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20240308220055.2172956-13-dave.jiang@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This commit is contained in:
Dave Jiang 2024-03-08 14:59:31 -07:00 committed by Dan Williams
parent 067353a46d
commit debdce20c4
6 changed files with 33 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

11
drivers/acpi/numa/srat.c
View file

@ -29,6 +29,8 @@ static int node_to_pxm_map[MAX_NUMNODES]
unsigned char acpi_srat_revision __initdata;
static int acpi_numa __initdata;
static int last_real_pxm;
void __init disable_srat(void)
{
acpi_numa = -1;
@ -536,6 +538,7 @@ int __init acpi_numa_init(void)
if (node_to_pxm_map[i] > fake_pxm)
fake_pxm = node_to_pxm_map[i];
}
last_real_pxm = fake_pxm;
fake_pxm++;
acpi_table_parse_cedt(ACPI_CEDT_TYPE_CFMWS, acpi_parse_cfmws,
&fake_pxm);
@ -547,6 +550,14 @@ int __init acpi_numa_init(void)
return 0;
}
bool acpi_node_backed_by_real_pxm(int nid)
{
int pxm = node_to_pxm(nid);
return pxm <= last_real_pxm;
}
EXPORT_SYMBOL_GPL(acpi_node_backed_by_real_pxm);
static int acpi_get_pxm(acpi_handle h)
{
unsigned long long pxm;

1
drivers/base/node.c
View file

@ -215,6 +215,7 @@ void node_set_perf_attrs(unsigned int nid, struct access_coordinate *coord,
}
}
}
EXPORT_SYMBOL_GPL(node_set_perf_attrs);
/**
* struct node_cache_info - Internal tracking for memory node caches

5
drivers/cxl/core/cdat.c
View file

@ -586,3 +586,8 @@ int cxl_update_hmat_access_coordinates(int nid, struct cxl_region *cxlr,
{
return hmat_update_target_coordinates(nid, &cxlr->coord[access], access);
}
bool cxl_need_node_perf_attrs_update(int nid)
{
return !acpi_node_backed_by_real_pxm(nid);
}

1
drivers/cxl/core/core.h
View file

@ -92,5 +92,6 @@ long cxl_pci_get_latency(struct pci_dev *pdev);
int cxl_update_hmat_access_coordinates(int nid, struct cxl_region *cxlr,
enum access_coordinate_class access);
bool cxl_need_node_perf_attrs_update(int nid);
#endif /* __CXL_CORE_H__ */

7
drivers/cxl/core/region.c
View file

@ -2279,7 +2279,12 @@ static bool cxl_region_update_coordinates(struct cxl_region *cxlr, int nid)
for (int i = 0; i < ACCESS_COORDINATE_MAX; i++) {
if (cxlr->coord[i].read_bandwidth) {
rc = cxl_update_hmat_access_coordinates(nid, cxlr, i);
rc = 0;
if (cxl_need_node_perf_attrs_update(nid))
node_set_perf_attrs(nid, &cxlr->coord[i], i);
else
rc = cxl_update_hmat_access_coordinates(nid, cxlr, i);
if (rc == 0)
cset++;
}

9
include/linux/acpi.h
View file

@ -1559,4 +1559,13 @@ static inline int hmat_update_target_coordinates(int nid,
}
#endif
#ifdef CONFIG_ACPI_NUMA
bool acpi_node_backed_by_real_pxm(int nid);
#else
static inline bool acpi_node_backed_by_real_pxm(int nid)
{
return false;
}
#endif
#endif /*_LINUX_ACPI_H*/