arch/powerpc/include/asm/topology.h | 15 +++-- arch/powerpc/mm/numa.c | 87 ++++++++++++++++++++++------- 2 files changed, 73 insertions(+), 29 deletions(-)
Coregroup support was only available on PowerPC on PowerVM LPARs.
However if firmware were to expose coregroup-id to the kernel, then
coregroup can even be supported on PowerNV too.
PowerPC Linux kernel will detect support for coregroup by looking at the
primary_domain_index. Till now on PowerNV systems, primary_domain_index
has been the penultimate domain in cpunode ibm,associativity device-tree
property. This would be taken as hint that coregroup support is not
available in the firmware.
If on PowerNV systems, primary_domain_index is not the penultimate
domain in cpunode ibm,associativity device-tree property, then it would
be taken as a hint that coregroup support is available in the firmware.
This logic makes it compatible with PowerVM Systems, where
primary_domain_index is not the penultimate domain in cpunode
ibm,associativity device-tree property.
$ lscpu
Architecture: ppc64le
Byte Order: Little Endian
CPU(s): 480
On-line CPU(s) list: 0-479
Thread(s) per core: 8
Core(s) per socket: 15
Socket(s): 4
NUMA node(s): 4
Model: 2.0 (pvr 0080 0200)
Model name: POWER10, altivec supported
CPU max MHz: 3249.0000
CPU min MHz: 3249.0000
L1d cache: 32K
L1i cache: 48K
L2 cache: 1024K
L3 cache: 4096K
NUMA node0 CPU(s): 0-119
NUMA node1 CPU(s): 120-239
NUMA node2 CPU(s): 240-359
NUMA node3 CPU(s): 360-479
with-out patched firmware and/or Linux-kernel
---------------------------------------------
$ grep -h -r . /sys/devices/system/cpu/*/topology/die_id |sort | uniq -c | sort -n -r
120 27
120 18
120 9
120 0
$ grep -h -r . /sys/devices/system/cpu/*/topology/die_cpus_list |sort | uniq -c | sort -n -r
120 360-479
120 240-359
120 120-239
120 0-119
with patched firmware and Linux-kernel
--------------------------------------
grep -h -r . /sys/devices/system/cpu/*/topology/die_id |sort | uniq -c | sort -n -r
64 6
64 4
64 2
64 0
56 7
56 5
56 3
56 1
grep -h -r . /sys/devices/system/cpu/*/topology/die_cpus_list |sort | uniq -c | sort -n -r
64 360-375,392-407,424-439,456-471
64 240-255,272-287,296-311,328-343
64 120-135,152-167,184-199,208-223
64 0-15,32-47,64-79,88-103
56 376-391,408-423,440-455,472-479
56 256-271,288-295,312-327,344-359
56 16-31,48-63,80-87,104-119
56 136-151,168-183,200-207,224-239
Observation:
Without the patched kernel and/or skiboot, die-id and numa were same.
With patched kernel and/or skiboot, we see 2 die-id per node.
Signed-off-by: Srikar Dronamraju <srikar@linux.ibm.com>
---
arch/powerpc/include/asm/topology.h | 15 +++--
arch/powerpc/mm/numa.c | 87 ++++++++++++++++++++++-------
2 files changed, 73 insertions(+), 29 deletions(-)
diff --git a/arch/powerpc/include/asm/topology.h b/arch/powerpc/include/asm/topology.h
index 66ed5fe1b718..568e6bc55726 100644
--- a/arch/powerpc/include/asm/topology.h
+++ b/arch/powerpc/include/asm/topology.h
@@ -71,6 +71,7 @@ extern void map_cpu_to_node(int cpu, int node);
extern void unmap_cpu_from_node(unsigned long cpu);
#endif /* CONFIG_HOTPLUG_CPU */
+extern int cpu_to_coregroup_id(int cpu);
#else
static inline int early_cpu_to_node(int cpu) { return 0; }
@@ -107,14 +108,6 @@ static inline void map_cpu_to_node(int cpu, int node) {}
static inline void unmap_cpu_from_node(unsigned long cpu) {}
#endif /* CONFIG_HOTPLUG_CPU */
#endif /* CONFIG_SMP */
-
-#endif /* CONFIG_NUMA */
-
-#if defined(CONFIG_NUMA) && defined(CONFIG_PPC_SPLPAR)
-void find_and_update_cpu_nid(int cpu);
-extern int cpu_to_coregroup_id(int cpu);
-#else
-static inline void find_and_update_cpu_nid(int cpu) {}
static inline int cpu_to_coregroup_id(int cpu)
{
#ifdef CONFIG_SMP
@@ -124,6 +117,12 @@ static inline int cpu_to_coregroup_id(int cpu)
#endif
}
+#endif /* CONFIG_NUMA */
+
+#if defined(CONFIG_NUMA) && defined(CONFIG_PPC_SPLPAR)
+void find_and_update_cpu_nid(int cpu);
+#else
+static inline void find_and_update_cpu_nid(int cpu) {}
#endif /* CONFIG_NUMA && CONFIG_PPC_SPLPAR */
#include <asm-generic/topology.h>
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index f4cf3ae036de..9b45cc9e1f27 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -432,7 +432,7 @@ static void __init initialize_form2_numa_distance_lookup_table(void)
static int __init find_primary_domain_index(void)
{
- int index;
+ int index = -1;
struct device_node *root;
/*
@@ -502,12 +502,9 @@ static int __init find_primary_domain_index(void)
distance_ref_points_depth = MAX_DISTANCE_REF_POINTS;
}
- of_node_put(root);
- return index;
-
err:
of_node_put(root);
- return -1;
+ return index;
}
static void __init get_n_mem_cells(int *n_addr_cells, int *n_size_cells)
@@ -892,12 +889,32 @@ static int __init numa_setup_drmem_lmb(struct drmem_lmb *lmb,
return 0;
}
+/*
+ * If hierarchy extends beyond primary_domain_index + 1, then next
+ * level corresponds to coregroup.
+ */
+static int detect_and_enable_coregroup(const __be32 *associativity, int index)
+{
+ if (!associativity)
+ return -1;
+
+ if (!index) {
+ index = of_read_number(associativity, 1);
+
+ if (index > primary_domain_index + 1)
+ coregroup_enabled = 1;
+ else
+ index = -1;
+ }
+ return index;
+}
+
static int __init parse_numa_properties(void)
{
struct device_node *memory, *pci;
- int default_nid = 0;
- unsigned long i;
+ int default_nid = 0, index = 0;
const __be32 *associativity;
+ unsigned long i;
if (numa_enabled == 0) {
pr_warn("disabled by user\n");
@@ -930,7 +947,6 @@ static int __init parse_numa_properties(void)
*/
for_each_present_cpu(i) {
__be32 vphn_assoc[VPHN_ASSOC_BUFSIZE];
- struct device_node *cpu;
int nid = NUMA_NO_NODE;
memset(vphn_assoc, 0, VPHN_ASSOC_BUFSIZE * sizeof(__be32));
@@ -938,7 +954,10 @@ static int __init parse_numa_properties(void)
if (__vphn_get_associativity(i, vphn_assoc) == 0) {
nid = associativity_to_nid(vphn_assoc);
initialize_form1_numa_distance(vphn_assoc);
+ if (!index)
+ index = detect_and_enable_coregroup(vphn_assoc, index);
} else {
+ struct device_node *cpu;
/*
* Don't fall back to default_nid yet -- we will plug
@@ -951,6 +970,8 @@ static int __init parse_numa_properties(void)
associativity = of_get_associativity(cpu);
if (associativity) {
nid = associativity_to_nid(associativity);
+ if (!index)
+ index = detect_and_enable_coregroup(associativity, index);
initialize_form1_numa_distance(associativity);
}
of_node_put(cpu);
@@ -1431,9 +1452,26 @@ void find_and_update_cpu_nid(int cpu)
pr_debug("%s:%d cpu %d nid %d\n", __func__, __LINE__, cpu, new_nid);
}
+static int topology_update_init(void)
+{
+ topology_inited = 1;
+ return 0;
+}
+device_initcall(topology_update_init);
+
+#else
+static long vphn_get_associativity(unsigned long cpu,
+ __be32 *associativity)
+{
+ return -1;
+}
+#endif /* CONFIG_PPC_SPLPAR */
+
int cpu_to_coregroup_id(int cpu)
{
- __be32 associativity[VPHN_ASSOC_BUFSIZE] = {0};
+ int coregroup_id = cpu_to_core_id(cpu);
+ struct device_node *cpunode = NULL;
+ const __be32 *associativity;
int index;
if (cpu < 0 || cpu > nr_cpu_ids)
@@ -1442,24 +1480,31 @@ int cpu_to_coregroup_id(int cpu)
if (!coregroup_enabled)
goto out;
- if (!firmware_has_feature(FW_FEATURE_VPHN))
- goto out;
+ if (firmware_has_feature(FW_FEATURE_VPHN)) {
+ __be32 tmp[VPHN_ASSOC_BUFSIZE] = {0};
- if (vphn_get_associativity(cpu, associativity))
+ if (vphn_get_associativity(cpu, tmp))
+ goto out;
+
+ associativity = tmp;
+
+ } else {
+ cpunode = of_get_cpu_node(cpu, NULL);
+ if (!cpunode)
+ goto out;
+
+ associativity = of_get_associativity(cpunode);
+ }
+ if (!associativity)
goto out;
index = of_read_number(associativity, 1);
if (index > primary_domain_index + 1)
- return of_read_number(&associativity[index - 1], 1);
+ coregroup_id = of_read_number(&associativity[index - 1], 1);
out:
- return cpu_to_core_id(cpu);
-}
+ if (cpunode)
+ of_node_put(cpunode);
-static int topology_update_init(void)
-{
- topology_inited = 1;
- return 0;
+ return coregroup_id;
}
-device_initcall(topology_update_init);
-#endif /* CONFIG_PPC_SPLPAR */
--
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