Commit 1c6b5a7e authored by Aneesh Kumar K.V's avatar Aneesh Kumar K.V Committed by Michael Ellerman

powerpc/pseries: Add support for FORM2 associativity

PAPR interface currently supports two different ways of communicating resource
grouping details to the OS. These are referred to as Form 0 and Form 1
associativity grouping. Form 0 is the older format and is now considered
deprecated. This patch adds another resource grouping named FORM2.
Signed-off-by: default avatarDaniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: default avatarAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210812132223.225214-6-aneesh.kumar@linux.ibm.com
parent ef31cb83
============================
NUMA resource associativity
=============================
Associativity represents the groupings of the various platform resources into
domains of substantially similar mean performance relative to resources outside
of that domain. Resources subsets of a given domain that exhibit better
performance relative to each other than relative to other resources subsets
are represented as being members of a sub-grouping domain. This performance
characteristic is presented in terms of NUMA node distance within the Linux kernel.
From the platform view, these groups are also referred to as domains.
PAPR interface currently supports different ways of communicating these resource
grouping details to the OS. These are referred to as Form 0, Form 1 and Form2
associativity grouping. Form 0 is the oldest format and is now considered deprecated.
Hypervisor indicates the type/form of associativity used via "ibm,architecture-vec-5 property".
Bit 0 of byte 5 in the "ibm,architecture-vec-5" property indicates usage of Form 0 or Form 1.
A value of 1 indicates the usage of Form 1 associativity. For Form 2 associativity
bit 2 of byte 5 in the "ibm,architecture-vec-5" property is used.
Form 0
-----
Form 0 associativity supports only two NUMA distances (LOCAL and REMOTE).
Form 1
-----
With Form 1 a combination of ibm,associativity-reference-points, and ibm,associativity
device tree properties are used to determine the NUMA distance between resource groups/domains.
The “ibm,associativity” property contains a list of one or more numbers (domainID)
representing the resource’s platform grouping domains.
The “ibm,associativity-reference-points” property contains a list of one or more numbers
(domainID index) that represents the 1 based ordinal in the associativity lists.
The list of domainID indexes represents an increasing hierarchy of resource grouping.
ex:
{ primary domainID index, secondary domainID index, tertiary domainID index.. }
Linux kernel uses the domainID at the primary domainID index as the NUMA node id.
Linux kernel computes NUMA distance between two domains by recursively comparing
if they belong to the same higher-level domains. For mismatch at every higher
level of the resource group, the kernel doubles the NUMA distance between the
comparing domains.
Form 2
-------
Form 2 associativity format adds separate device tree properties representing NUMA node distance
thereby making the node distance computation flexible. Form 2 also allows flexible primary
domain numbering. With numa distance computation now detached from the index value in
"ibm,associativity-reference-points" property, Form 2 allows a large number of primary domain
ids at the same domainID index representing resource groups of different performance/latency
characteristics.
Hypervisor indicates the usage of FORM2 associativity using bit 2 of byte 5 in the
"ibm,architecture-vec-5" property.
"ibm,numa-lookup-index-table" property contains a list of one or more numbers representing
the domainIDs present in the system. The offset of the domainID in this property is
used as an index while computing numa distance information via "ibm,numa-distance-table".
prop-encoded-array: The number N of the domainIDs encoded as with encode-int, followed by
N domainID encoded as with encode-int
For ex:
"ibm,numa-lookup-index-table" = {4, 0, 8, 250, 252}. The offset of domainID 8 (2) is used when
computing the distance of domain 8 from other domains present in the system. For the rest of
this document, this offset will be referred to as domain distance offset.
"ibm,numa-distance-table" property contains a list of one or more numbers representing the NUMA
distance between resource groups/domains present in the system.
prop-encoded-array: The number N of the distance values encoded as with encode-int, followed by
N distance values encoded as with encode-bytes. The max distance value we could encode is 255.
The number N must be equal to the square of m where m is the number of domainIDs in the
numa-lookup-index-table.
For ex:
ibm,numa-lookup-index-table = <3 0 8 40>;
ibm,numa-distace-table = <9>, /bits/ 8 < 10 20 80
20 10 160
80 160 10>;
| 0 8 40
--|------------
|
0 | 10 20 80
|
8 | 20 10 160
|
40| 80 160 10
A possible "ibm,associativity" property for resources in node 0, 8 and 40
{ 3, 6, 7, 0 }
{ 3, 6, 9, 8 }
{ 3, 6, 7, 40}
With "ibm,associativity-reference-points" { 0x3 }
"ibm,lookup-index-table" helps in having a compact representation of distance matrix.
Since domainID can be sparse, the matrix of distances can also be effectively sparse.
With "ibm,lookup-index-table" we can achieve a compact representation of
distance information.
......@@ -53,6 +53,7 @@
#define FW_FEATURE_ULTRAVISOR ASM_CONST(0x0000004000000000)
#define FW_FEATURE_STUFF_TCE ASM_CONST(0x0000008000000000)
#define FW_FEATURE_RPT_INVALIDATE ASM_CONST(0x0000010000000000)
#define FW_FEATURE_FORM2_AFFINITY ASM_CONST(0x0000020000000000)
#ifndef __ASSEMBLY__
......@@ -73,7 +74,7 @@ enum {
FW_FEATURE_HPT_RESIZE | FW_FEATURE_DRMEM_V2 |
FW_FEATURE_DRC_INFO | FW_FEATURE_BLOCK_REMOVE |
FW_FEATURE_PAPR_SCM | FW_FEATURE_ULTRAVISOR |
FW_FEATURE_RPT_INVALIDATE,
FW_FEATURE_RPT_INVALIDATE | FW_FEATURE_FORM2_AFFINITY,
FW_FEATURE_PSERIES_ALWAYS = 0,
FW_FEATURE_POWERNV_POSSIBLE = FW_FEATURE_OPAL | FW_FEATURE_ULTRAVISOR,
FW_FEATURE_POWERNV_ALWAYS = 0,
......
......@@ -149,6 +149,7 @@ extern int of_read_drc_info_cell(struct property **prop,
#define OV5_XCMO 0x0440 /* Page Coalescing */
#define OV5_FORM1_AFFINITY 0x0580 /* FORM1 NUMA affinity */
#define OV5_PRRN 0x0540 /* Platform Resource Reassignment */
#define OV5_FORM2_AFFINITY 0x0520 /* Form2 NUMA affinity */
#define OV5_HP_EVT 0x0604 /* Hot Plug Event support */
#define OV5_RESIZE_HPT 0x0601 /* Hash Page Table resizing */
#define OV5_PFO_HW_RNG 0x1180 /* PFO Random Number Generator */
......
......@@ -1096,7 +1096,8 @@ static const struct ibm_arch_vec ibm_architecture_vec_template __initconst = {
#else
0,
#endif
.associativity = OV5_FEAT(OV5_FORM1_AFFINITY) | OV5_FEAT(OV5_PRRN),
.associativity = OV5_FEAT(OV5_FORM1_AFFINITY) | OV5_FEAT(OV5_PRRN) |
OV5_FEAT(OV5_FORM2_AFFINITY),
.bin_opts = OV5_FEAT(OV5_RESIZE_HPT) | OV5_FEAT(OV5_HP_EVT),
.micro_checkpoint = 0,
.reserved0 = 0,
......
......@@ -56,12 +56,17 @@ static int n_mem_addr_cells, n_mem_size_cells;
#define FORM0_AFFINITY 0
#define FORM1_AFFINITY 1
#define FORM2_AFFINITY 2
static int affinity_form;
#define MAX_DISTANCE_REF_POINTS 4
static int distance_ref_points_depth;
static const __be32 *distance_ref_points;
static int distance_lookup_table[MAX_NUMNODES][MAX_DISTANCE_REF_POINTS];
static int numa_distance_table[MAX_NUMNODES][MAX_NUMNODES] = {
[0 ... MAX_NUMNODES - 1] = { [0 ... MAX_NUMNODES - 1] = -1 }
};
static int numa_id_index_table[MAX_NUMNODES] = { [0 ... MAX_NUMNODES - 1] = NUMA_NO_NODE };
/*
* Allocate node_to_cpumask_map based on number of available nodes
......@@ -166,6 +171,54 @@ static void unmap_cpu_from_node(unsigned long cpu)
}
#endif /* CONFIG_HOTPLUG_CPU || CONFIG_PPC_SPLPAR */
static int __associativity_to_nid(const __be32 *associativity,
int max_array_sz)
{
int nid;
/*
* primary_domain_index is 1 based array index.
*/
int index = primary_domain_index - 1;
if (!numa_enabled || index >= max_array_sz)
return NUMA_NO_NODE;
nid = of_read_number(&associativity[index], 1);
/* POWER4 LPAR uses 0xffff as invalid node */
if (nid == 0xffff || nid >= nr_node_ids)
nid = NUMA_NO_NODE;
return nid;
}
/*
* Returns nid in the range [0..nr_node_ids], or -1 if no useful NUMA
* info is found.
*/
static int associativity_to_nid(const __be32 *associativity)
{
int array_sz = of_read_number(associativity, 1);
/* Skip the first element in the associativity array */
return __associativity_to_nid((associativity + 1), array_sz);
}
static int __cpu_form2_relative_distance(__be32 *cpu1_assoc, __be32 *cpu2_assoc)
{
int dist;
int node1, node2;
node1 = associativity_to_nid(cpu1_assoc);
node2 = associativity_to_nid(cpu2_assoc);
dist = numa_distance_table[node1][node2];
if (dist <= LOCAL_DISTANCE)
return 0;
else if (dist <= REMOTE_DISTANCE)
return 1;
else
return 2;
}
static int __cpu_form1_relative_distance(__be32 *cpu1_assoc, __be32 *cpu2_assoc)
{
int dist = 0;
......@@ -186,8 +239,9 @@ int cpu_relative_distance(__be32 *cpu1_assoc, __be32 *cpu2_assoc)
{
/* We should not get called with FORM0 */
VM_WARN_ON(affinity_form == FORM0_AFFINITY);
if (affinity_form == FORM1_AFFINITY)
return __cpu_form1_relative_distance(cpu1_assoc, cpu2_assoc);
return __cpu_form2_relative_distance(cpu1_assoc, cpu2_assoc);
}
/* must hold reference to node during call */
......@@ -201,7 +255,9 @@ int __node_distance(int a, int b)
int i;
int distance = LOCAL_DISTANCE;
if (affinity_form == FORM0_AFFINITY)
if (affinity_form == FORM2_AFFINITY)
return numa_distance_table[a][b];
else if (affinity_form == FORM0_AFFINITY)
return ((a == b) ? LOCAL_DISTANCE : REMOTE_DISTANCE);
for (i = 0; i < distance_ref_points_depth; i++) {
......@@ -216,37 +272,6 @@ int __node_distance(int a, int b)
}
EXPORT_SYMBOL(__node_distance);
static int __associativity_to_nid(const __be32 *associativity,
int max_array_sz)
{
int nid;
/*
* primary_domain_index is 1 based array index.
*/
int index = primary_domain_index - 1;
if (!numa_enabled || index >= max_array_sz)
return NUMA_NO_NODE;
nid = of_read_number(&associativity[index], 1);
/* POWER4 LPAR uses 0xffff as invalid node */
if (nid == 0xffff || nid >= nr_node_ids)
nid = NUMA_NO_NODE;
return nid;
}
/*
* Returns nid in the range [0..nr_node_ids], or -1 if no useful NUMA
* info is found.
*/
static int associativity_to_nid(const __be32 *associativity)
{
int array_sz = of_read_number(associativity, 1);
/* Skip the first element in the associativity array */
return __associativity_to_nid((associativity + 1), array_sz);
}
/* Returns the nid associated with the given device tree node,
* or -1 if not found.
*/
......@@ -320,6 +345,8 @@ static void initialize_form1_numa_distance(const __be32 *associativity)
*/
void update_numa_distance(struct device_node *node)
{
int nid;
if (affinity_form == FORM0_AFFINITY)
return;
else if (affinity_form == FORM1_AFFINITY) {
......@@ -332,6 +359,84 @@ void update_numa_distance(struct device_node *node)
initialize_form1_numa_distance(associativity);
return;
}
/* FORM2 affinity */
nid = of_node_to_nid_single(node);
if (nid == NUMA_NO_NODE)
return;
/*
* With FORM2 we expect NUMA distance of all possible NUMA
* nodes to be provided during boot.
*/
WARN(numa_distance_table[nid][nid] == -1,
"NUMA distance details for node %d not provided\n", nid);
}
/*
* ibm,numa-lookup-index-table= {N, domainid1, domainid2, ..... domainidN}
* ibm,numa-distance-table = { N, 1, 2, 4, 5, 1, 6, .... N elements}
*/
static void initialize_form2_numa_distance_lookup_table(void)
{
int i, j;
struct device_node *root;
const __u8 *numa_dist_table;
const __be32 *numa_lookup_index;
int numa_dist_table_length;
int max_numa_index, distance_index;
if (firmware_has_feature(FW_FEATURE_OPAL))
root = of_find_node_by_path("/ibm,opal");
else
root = of_find_node_by_path("/rtas");
if (!root)
root = of_find_node_by_path("/");
numa_lookup_index = of_get_property(root, "ibm,numa-lookup-index-table", NULL);
max_numa_index = of_read_number(&numa_lookup_index[0], 1);
/* first element of the array is the size and is encode-int */
numa_dist_table = of_get_property(root, "ibm,numa-distance-table", NULL);
numa_dist_table_length = of_read_number((const __be32 *)&numa_dist_table[0], 1);
/* Skip the size which is encoded int */
numa_dist_table += sizeof(__be32);
pr_debug("numa_dist_table_len = %d, numa_dist_indexes_len = %d\n",
numa_dist_table_length, max_numa_index);
for (i = 0; i < max_numa_index; i++)
/* +1 skip the max_numa_index in the property */
numa_id_index_table[i] = of_read_number(&numa_lookup_index[i + 1], 1);
if (numa_dist_table_length != max_numa_index * max_numa_index) {
WARN(1, "Wrong NUMA distance information\n");
/* consider everybody else just remote. */
for (i = 0; i < max_numa_index; i++) {
for (j = 0; j < max_numa_index; j++) {
int nodeA = numa_id_index_table[i];
int nodeB = numa_id_index_table[j];
if (nodeA == nodeB)
numa_distance_table[nodeA][nodeB] = LOCAL_DISTANCE;
else
numa_distance_table[nodeA][nodeB] = REMOTE_DISTANCE;
}
}
}
distance_index = 0;
for (i = 0; i < max_numa_index; i++) {
for (j = 0; j < max_numa_index; j++) {
int nodeA = numa_id_index_table[i];
int nodeB = numa_id_index_table[j];
numa_distance_table[nodeA][nodeB] = numa_dist_table[distance_index++];
pr_debug("dist[%d][%d]=%d ", nodeA, nodeB, numa_distance_table[nodeA][nodeB]);
}
}
of_node_put(root);
}
static int __init find_primary_domain_index(void)
......@@ -344,6 +449,9 @@ static int __init find_primary_domain_index(void)
*/
if (firmware_has_feature(FW_FEATURE_OPAL)) {
affinity_form = FORM1_AFFINITY;
} else if (firmware_has_feature(FW_FEATURE_FORM2_AFFINITY)) {
dbg("Using form 2 affinity\n");
affinity_form = FORM2_AFFINITY;
} else if (firmware_has_feature(FW_FEATURE_FORM1_AFFINITY)) {
dbg("Using form 1 affinity\n");
affinity_form = FORM1_AFFINITY;
......@@ -388,9 +496,12 @@ static int __init find_primary_domain_index(void)
index = of_read_number(&distance_ref_points[1], 1);
} else {
/*
* Both FORM1 and FORM2 affinity find the primary domain details
* at the same offset.
*/
index = of_read_number(distance_ref_points, 1);
}
/*
* Warn and cap if the hardware supports more than
* MAX_DISTANCE_REF_POINTS domains.
......@@ -819,6 +930,12 @@ static int __init parse_numa_properties(void)
dbg("NUMA associativity depth for CPU/Memory: %d\n", primary_domain_index);
/*
* If it is FORM2 initialize the distance table here.
*/
if (affinity_form == FORM2_AFFINITY)
initialize_form2_numa_distance_lookup_table();
/*
* Even though we connect cpus to numa domains later in SMP
* init, we need to know the node ids now. This is because
......
......@@ -123,6 +123,7 @@ vec5_fw_features_table[] = {
{FW_FEATURE_PRRN, OV5_PRRN},
{FW_FEATURE_DRMEM_V2, OV5_DRMEM_V2},
{FW_FEATURE_DRC_INFO, OV5_DRC_INFO},
{FW_FEATURE_FORM2_AFFINITY, OV5_FORM2_AFFINITY},
};
static void __init fw_vec5_feature_init(const char *vec5, unsigned long len)
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment