sparc64: Fix numa distance values

Orabug: 21896119

Use machine descriptor (MD) to get node latency
values instead of just using default values.

Testing:
On an T5-8 system with:
 - total nodes = 8
 - self latencies = 0x26d18
 - latency to other nodes = 0x3a598
   => latency ratio = ~1.5

output of numactl --hardware

 - before fix:

node distances:
node   0   1   2   3   4   5   6   7
  0:  10  20  20  20  20  20  20  20
  1:  20  10  20  20  20  20  20  20
  2:  20  20  10  20  20  20  20  20
  3:  20  20  20  10  20  20  20  20
  4:  20  20  20  20  10  20  20  20
  5:  20  20  20  20  20  10  20  20
  6:  20  20  20  20  20  20  10  20
  7:  20  20  20  20  20  20  20  10

 - after fix:

node distances:
node   0   1   2   3   4   5   6   7
  0:  10  15  15  15  15  15  15  15
  1:  15  10  15  15  15  15  15  15
  2:  15  15  10  15  15  15  15  15
  3:  15  15  15  10  15  15  15  15
  4:  15  15  15  15  10  15  15  15
  5:  15  15  15  15  15  10  15  15
  6:  15  15  15  15  15  15  10  15
  7:  15  15  15  15  15  15  15  10

Signed-off-by: Nitin Gupta <nitin.m.gupta@oracle.com>
Reviewed-by: Chris Hyser <chris.hyser@oracle.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Nitin Gupta 2015-11-02 16:30:24 -05:00 committed by David S. Miller
parent cae9af6a82
commit 52708d690b
2 changed files with 72 additions and 1 deletions

View File

@ -31,6 +31,9 @@ static inline int pcibus_to_node(struct pci_bus *pbus)
cpu_all_mask : \
cpumask_of_node(pcibus_to_node(bus)))
int __node_distance(int, int);
#define node_distance(a, b) __node_distance(a, b)
#else /* CONFIG_NUMA */
#include <asm-generic/topology.h>

View File

@ -93,6 +93,8 @@ static unsigned long cpu_pgsz_mask;
static struct linux_prom64_registers pavail[MAX_BANKS];
static int pavail_ents;
u64 numa_latency[MAX_NUMNODES][MAX_NUMNODES];
static int cmp_p64(const void *a, const void *b)
{
const struct linux_prom64_registers *x = a, *y = b;
@ -1157,6 +1159,48 @@ static struct mdesc_mlgroup * __init find_mlgroup(u64 node)
return NULL;
}
int __node_distance(int from, int to)
{
if ((from >= MAX_NUMNODES) || (to >= MAX_NUMNODES)) {
pr_warn("Returning default NUMA distance value for %d->%d\n",
from, to);
return (from == to) ? LOCAL_DISTANCE : REMOTE_DISTANCE;
}
return numa_latency[from][to];
}
static int find_best_numa_node_for_mlgroup(struct mdesc_mlgroup *grp)
{
int i;
for (i = 0; i < MAX_NUMNODES; i++) {
struct node_mem_mask *n = &node_masks[i];
if ((grp->mask == n->mask) && (grp->match == n->val))
break;
}
return i;
}
static void find_numa_latencies_for_group(struct mdesc_handle *md, u64 grp,
int index)
{
u64 arc;
mdesc_for_each_arc(arc, md, grp, MDESC_ARC_TYPE_FWD) {
int tnode;
u64 target = mdesc_arc_target(md, arc);
struct mdesc_mlgroup *m = find_mlgroup(target);
if (!m)
continue;
tnode = find_best_numa_node_for_mlgroup(m);
if (tnode == MAX_NUMNODES)
continue;
numa_latency[index][tnode] = m->latency;
}
}
static int __init numa_attach_mlgroup(struct mdesc_handle *md, u64 grp,
int index)
{
@ -1220,9 +1264,16 @@ static int __init numa_parse_mdesc_group(struct mdesc_handle *md, u64 grp,
static int __init numa_parse_mdesc(void)
{
struct mdesc_handle *md = mdesc_grab();
int i, err, count;
int i, j, err, count;
u64 node;
/* Some sane defaults for numa latency values */
for (i = 0; i < MAX_NUMNODES; i++) {
for (j = 0; j < MAX_NUMNODES; j++)
numa_latency[i][j] = (i == j) ?
LOCAL_DISTANCE : REMOTE_DISTANCE;
}
node = mdesc_node_by_name(md, MDESC_NODE_NULL, "latency-groups");
if (node == MDESC_NODE_NULL) {
mdesc_release(md);
@ -1245,6 +1296,23 @@ static int __init numa_parse_mdesc(void)
count++;
}
count = 0;
mdesc_for_each_node_by_name(md, node, "group") {
find_numa_latencies_for_group(md, node, count);
count++;
}
/* Normalize numa latency matrix according to ACPI SLIT spec. */
for (i = 0; i < MAX_NUMNODES; i++) {
u64 self_latency = numa_latency[i][i];
for (j = 0; j < MAX_NUMNODES; j++) {
numa_latency[i][j] =
(numa_latency[i][j] * LOCAL_DISTANCE) /
self_latency;
}
}
add_node_ranges();
for (i = 0; i < num_node_masks; i++) {