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-rw-r--r--arch/powerpc/mm/numa.c100
1 files changed, 58 insertions, 42 deletions
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index f976676004ad..50d68d21ddcc 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -1,12 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
/*
* pSeries NUMA support
*
* Copyright (C) 2002 Anton Blanchard <anton@au.ibm.com>, IBM
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
*/
#define pr_fmt(fmt) "numa: " fmt
@@ -32,7 +28,6 @@
#include <asm/sparsemem.h>
#include <asm/prom.h>
#include <asm/smp.h>
-#include <asm/cputhreads.h>
#include <asm/topology.h>
#include <asm/firmware.h>
#include <asm/paca.h>
@@ -168,6 +163,22 @@ static void unmap_cpu_from_node(unsigned long cpu)
}
#endif /* CONFIG_HOTPLUG_CPU || CONFIG_PPC_SPLPAR */
+int cpu_distance(__be32 *cpu1_assoc, __be32 *cpu2_assoc)
+{
+ int dist = 0;
+
+ int i, index;
+
+ for (i = 0; i < distance_ref_points_depth; i++) {
+ index = be32_to_cpu(distance_ref_points[i]);
+ if (cpu1_assoc[index] == cpu2_assoc[index])
+ break;
+ dist++;
+ }
+
+ return dist;
+}
+
/* must hold reference to node during call */
static const __be32 *of_get_associativity(struct device_node *dev)
{
@@ -217,7 +228,7 @@ static int associativity_to_nid(const __be32 *associativity)
{
int nid = NUMA_NO_NODE;
- if (min_common_depth == -1)
+ if (!numa_enabled)
goto out;
if (of_read_number(associativity, 1) >= min_common_depth)
@@ -421,17 +432,19 @@ static int of_get_assoc_arrays(struct assoc_arrays *aa)
static int of_drconf_to_nid_single(struct drmem_lmb *lmb)
{
struct assoc_arrays aa = { .arrays = NULL };
- int default_nid = 0;
+ int default_nid = NUMA_NO_NODE;
int nid = default_nid;
int rc, index;
+ if ((min_common_depth < 0) || !numa_enabled)
+ return default_nid;
+
rc = of_get_assoc_arrays(&aa);
if (rc)
return default_nid;
- if (min_common_depth > 0 && min_common_depth <= aa.array_sz &&
- !(lmb->flags & DRCONF_MEM_AI_INVALID) &&
- lmb->aa_index < aa.n_arrays) {
+ if (min_common_depth <= aa.array_sz &&
+ !(lmb->flags & DRCONF_MEM_AI_INVALID) && lmb->aa_index < aa.n_arrays) {
index = lmb->aa_index * aa.array_sz + min_common_depth - 1;
nid = of_read_number(&aa.arrays[index], 1);
@@ -631,8 +644,14 @@ static int __init parse_numa_properties(void)
min_common_depth = find_min_common_depth();
- if (min_common_depth < 0)
+ if (min_common_depth < 0) {
+ /*
+ * if we fail to parse min_common_depth from device tree
+ * mark the numa disabled, boot with numa disabled.
+ */
+ numa_enabled = false;
return min_common_depth;
+ }
dbg("NUMA associativity depth for CPU/Memory: %d\n", min_common_depth);
@@ -748,7 +767,7 @@ void __init dump_numa_cpu_topology(void)
unsigned int node;
unsigned int cpu, count;
- if (min_common_depth == -1 || !numa_enabled)
+ if (!numa_enabled)
return;
for_each_online_node(node) {
@@ -813,7 +832,7 @@ static void __init find_possible_nodes(void)
struct device_node *rtas;
u32 numnodes, i;
- if (min_common_depth <= 0)
+ if (!numa_enabled)
return;
rtas = of_find_node_by_path("/rtas");
@@ -908,16 +927,22 @@ static int __init early_numa(char *p)
}
early_param("numa", early_numa);
-static bool topology_updates_enabled = true;
+/*
+ * The platform can inform us through one of several mechanisms
+ * (post-migration device tree updates, PRRN or VPHN) that the NUMA
+ * assignment of a resource has changed. This controls whether we act
+ * on that. Disabled by default.
+ */
+static bool topology_updates_enabled;
static int __init early_topology_updates(char *p)
{
if (!p)
return 0;
- if (!strcmp(p, "off")) {
- pr_info("Disabling topology updates\n");
- topology_updates_enabled = false;
+ if (!strcmp(p, "on")) {
+ pr_warn("Caution: enabling topology updates\n");
+ topology_updates_enabled = true;
}
return 0;
@@ -1009,7 +1034,7 @@ int hot_add_scn_to_nid(unsigned long scn_addr)
struct device_node *memory = NULL;
int nid;
- if (!numa_enabled || (min_common_depth < 0))
+ if (!numa_enabled)
return first_online_node;
memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
@@ -1062,9 +1087,6 @@ u64 memory_hotplug_max(void)
/* Virtual Processor Home Node (VPHN) support */
#ifdef CONFIG_PPC_SPLPAR
-
-#include "vphn.h"
-
struct topology_update_data {
struct topology_update_data *next;
unsigned int cpu;
@@ -1160,25 +1182,13 @@ static int update_cpu_associativity_changes_mask(void)
* Retrieve the new associativity information for a virtual processor's
* home node.
*/
-static long hcall_vphn(unsigned long cpu, __be32 *associativity)
-{
- long rc;
- long retbuf[PLPAR_HCALL9_BUFSIZE] = {0};
- u64 flags = 1;
- int hwcpu = get_hard_smp_processor_id(cpu);
-
- rc = plpar_hcall9(H_HOME_NODE_ASSOCIATIVITY, retbuf, flags, hwcpu);
- vphn_unpack_associativity(retbuf, associativity);
-
- return rc;
-}
-
static long vphn_get_associativity(unsigned long cpu,
__be32 *associativity)
{
long rc;
- rc = hcall_vphn(cpu, associativity);
+ rc = hcall_vphn(get_hard_smp_processor_id(cpu),
+ VPHN_FLAG_VCPU, associativity);
switch (rc) {
case H_FUNCTION:
@@ -1498,6 +1508,9 @@ int start_topology_update(void)
{
int rc = 0;
+ if (!topology_updates_enabled)
+ return 0;
+
if (firmware_has_feature(FW_FEATURE_PRRN)) {
if (!prrn_enabled) {
prrn_enabled = 1;
@@ -1531,6 +1544,9 @@ int stop_topology_update(void)
{
int rc = 0;
+ if (!topology_updates_enabled)
+ return 0;
+
if (prrn_enabled) {
prrn_enabled = 0;
#ifdef CONFIG_SMP
@@ -1588,11 +1604,13 @@ static ssize_t topology_write(struct file *file, const char __user *buf,
kbuf[read_len] = '\0';
- if (!strncmp(kbuf, "on", 2))
+ if (!strncmp(kbuf, "on", 2)) {
+ topology_updates_enabled = true;
start_topology_update();
- else if (!strncmp(kbuf, "off", 3))
+ } else if (!strncmp(kbuf, "off", 3)) {
stop_topology_update();
- else
+ topology_updates_enabled = false;
+ } else
return -EINVAL;
return count;
@@ -1607,9 +1625,7 @@ static const struct file_operations topology_ops = {
static int topology_update_init(void)
{
- /* Do not poll for changes if disabled at boot */
- if (topology_updates_enabled)
- start_topology_update();
+ start_topology_update();
if (vphn_enabled)
topology_schedule_update();
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