Commit 52708d69 authored by Nitin Gupta's avatar Nitin Gupta Committed by David S. Miller
Browse files

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: default avatarNitin Gupta <nitin.m.gupta@oracle.com>
Reviewed-by: default avatarChris Hyser <chris.hyser@oracle.com>
Reviewed-by: default avatarSantosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent cae9af6a

arch/sparc/include/asm/topology_64.h

+3 −0
Original line number Diff line number Diff line
@@ -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>

arch/sparc/mm/init_64.c

+69 −1
Original line number Diff line number Diff line
@@ -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++) {

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