s390/numa: make core to node mapping data dynamic
The core to node mapping data consumes about 2 KB bss data. To save memory
for the non-NUMA case, make the data dynamic. In addition change the
"core_to_node" array from "int" to "s32" which saves 1 KB also for the
NUMA case.
Suggested-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/numa/mode_emu.c b/arch/s390/numa/mode_emu.c
index 646cd94..7de4e2f 100644
--- a/arch/s390/numa/mode_emu.c
+++ b/arch/s390/numa/mode_emu.c
@@ -23,6 +23,7 @@
#include <linux/memblock.h>
#include <linux/node.h>
#include <linux/memory.h>
+#include <linux/slab.h>
#include <asm/smp.h>
#include <asm/topology.h>
#include "numa_mode.h"
@@ -56,26 +57,24 @@
* Node to core pinning information updates are protected by
* "sched_domains_mutex".
*/
-/* Pinned core to node mapping */
-static int cores_to_node_id[CONFIG_NR_CPUS];
-/* Total number of pinned cores */
-static int cores_total;
-/* Number of cores per node without extra cores */
-static int cores_per_node_target;
-/* Number of cores pinned to node */
-static int cores_per_node[MAX_NUMNODES];
+static struct {
+ s32 to_node_id[CONFIG_NR_CPUS]; /* Pinned core to node mapping */
+ int total; /* Total number of pinned cores */
+ int per_node_target; /* Cores per node without extra cores */
+ int per_node[MAX_NUMNODES]; /* Number of cores pinned to node */
+} *emu_cores;
/*
* Pin a core to a node
*/
static void pin_core_to_node(int core_id, int node_id)
{
- if (cores_to_node_id[core_id] == NODE_ID_FREE) {
- cores_per_node[node_id]++;
- cores_to_node_id[core_id] = node_id;
- cores_total++;
+ if (emu_cores->to_node_id[core_id] == NODE_ID_FREE) {
+ emu_cores->per_node[node_id]++;
+ emu_cores->to_node_id[core_id] = node_id;
+ emu_cores->total++;
} else {
- WARN_ON(cores_to_node_id[core_id] != node_id);
+ WARN_ON(emu_cores->to_node_id[core_id] != node_id);
}
}
@@ -84,7 +83,7 @@
*/
static int cores_pinned(struct toptree *node)
{
- return cores_per_node[node->id];
+ return emu_cores->per_node[node->id];
}
/*
@@ -92,7 +91,7 @@
*/
static int core_pinned_to_node_id(struct toptree *core)
{
- return cores_to_node_id[core->id];
+ return emu_cores->to_node_id[core->id];
}
/*
@@ -174,14 +173,15 @@
/*
* Find the best/nearest node for a given core and ensure that no node
- * gets more than "cores_per_node_target + extra" cores.
+ * gets more than "emu_cores->per_node_target + extra" cores.
*/
static struct toptree *node_for_core(struct toptree *numa, struct toptree *core,
int extra)
{
struct toptree *node, *node_best = NULL;
- int dist_cur, dist_best;
+ int dist_cur, dist_best, cores_target;
+ cores_target = emu_cores->per_node_target + extra;
dist_best = DIST_MAX;
node_best = NULL;
toptree_for_each(node, numa, NODE) {
@@ -191,7 +191,7 @@
break;
}
/* Skip nodes that already have enough cores */
- if (cores_pinned(node) >= cores_per_node_target + extra)
+ if (cores_pinned(node) >= cores_target)
continue;
dist_cur = dist_node_to_core(node, core);
if (dist_cur < dist_best) {
@@ -225,11 +225,11 @@
static void move_level_to_numa_node(struct toptree *node, struct toptree *phys,
enum toptree_level level, bool perfect)
{
+ int cores_free, cores_target = emu_cores->per_node_target;
struct toptree *cur, *tmp;
- int cores_free;
toptree_for_each_safe(cur, tmp, phys, level) {
- cores_free = cores_per_node_target - toptree_count(node, CORE);
+ cores_free = cores_target - toptree_count(node, CORE);
if (perfect) {
if (cores_free == toptree_count(cur, CORE))
toptree_move(cur, node);
@@ -292,6 +292,20 @@
}
/*
+ * Allocate and initialize core to node mapping
+ */
+static void create_core_to_node_map(void)
+{
+ int i;
+
+ emu_cores = kzalloc(sizeof(*emu_cores), GFP_KERNEL);
+ if (emu_cores == NULL)
+ panic("Could not allocate cores to node memory");
+ for (i = 0; i < ARRAY_SIZE(emu_cores->to_node_id); i++)
+ emu_cores->to_node_id[i] = NODE_ID_FREE;
+}
+
+/*
* Move cores from physical topology into NUMA target topology
* and try to keep as much of the physical topology as possible.
*/
@@ -299,8 +313,10 @@
{
static int first = 1;
struct toptree *numa;
+ int cores_total;
- cores_per_node_target = (cores_total + cores_free(phys)) / emu_nodes;
+ cores_total = emu_cores->total + cores_free(phys);
+ emu_cores->per_node_target = cores_total / emu_nodes;
numa = toptree_new(TOPTREE_ID_NUMA, emu_nodes);
if (first) {
toptree_to_numa_first(numa, phys);
@@ -386,8 +402,8 @@
printk(KERN_DEBUG "NUMA node to core mapping\n");
for (nid = 0; nid < emu_nodes; nid++) {
printk(KERN_DEBUG " node %3d: ", nid);
- for (cid = 0; cid < ARRAY_SIZE(cores_to_node_id); cid++) {
- if (cores_to_node_id[cid] == nid)
+ for (cid = 0; cid < ARRAY_SIZE(emu_cores->to_node_id); cid++) {
+ if (emu_cores->to_node_id[cid] == nid)
printk(KERN_CONT "%d ", cid);
}
printk(KERN_CONT "\n");
@@ -404,6 +420,8 @@
{
struct toptree *phys, *numa;
+ if (emu_cores == NULL)
+ create_core_to_node_map();
phys = toptree_from_topology();
numa = toptree_to_numa(phys);
toptree_free(phys);
@@ -443,12 +461,8 @@
*/
static void emu_setup(void)
{
- int i;
-
emu_size = emu_setup_size_adjust(emu_size);
emu_nodes = emu_setup_nodes_adjust(emu_nodes);
- for (i = 0; i < ARRAY_SIZE(cores_to_node_id); i++)
- cores_to_node_id[i] = NODE_ID_FREE;
pr_info("Creating %d nodes with memory stripe size %ld MB\n",
emu_nodes, emu_size >> 20);
}
