1 files changed, 216 insertions, 62 deletions

diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index fa33c546e778..88c0425dc0a8 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -22,6 +22,10 @@
 #include <linux/pfn.h>
 #include <linux/cpuset.h>
 #include <linux/node.h>
+#include <linux/stop_machine.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/uaccess.h>
 #include <linux/slab.h>
 #include <asm/sparsemem.h>
 #include <asm/prom.h>
@@ -30,6 +34,7 @@
 #include <asm/paca.h>
 #include <asm/hvcall.h>
 #include <asm/setup.h>
+#include <asm/vdso.h>
 
 static int numa_enabled = 1;
 
@@ -77,7 +82,7 @@ static void __init setup_node_to_cpumask_map(void)
 	dbg("Node to cpumask map for %d nodes\n", nr_node_ids);
 }
 
-static int __cpuinit fake_numa_create_new_node(unsigned long end_pfn,
+static int __init fake_numa_create_new_node(unsigned long end_pfn,
 						unsigned int *nid)
 {
 	unsigned long long mem;
@@ -199,7 +204,7 @@ int __node_distance(int a, int b)
 	int distance = LOCAL_DISTANCE;
 
 	if (!form1_affinity)
-		return distance;
+		return ((a == b) ? LOCAL_DISTANCE : REMOTE_DISTANCE);
 
 	for (i = 0; i < distance_ref_points_depth; i++) {
 		if (distance_lookup_table[a][i] == distance_lookup_table[b][i])
@@ -289,9 +294,7 @@ EXPORT_SYMBOL_GPL(of_node_to_nid);
 static int __init find_min_common_depth(void)
 {
 	int depth;
-	struct device_node *chosen;
 	struct device_node *root;
-	const char *vec5;
 
 	if (firmware_has_feature(FW_FEATURE_OPAL))
 		root = of_find_node_by_path("/ibm,opal");
@@ -323,24 +326,10 @@ static int __init find_min_common_depth(void)
 
 	distance_ref_points_depth /= sizeof(int);
 
-#define VEC5_AFFINITY_BYTE	5
-#define VEC5_AFFINITY		0x80
-
-	if (firmware_has_feature(FW_FEATURE_OPAL))
+	if (firmware_has_feature(FW_FEATURE_OPAL) ||
+	    firmware_has_feature(FW_FEATURE_TYPE1_AFFINITY)) {
+		dbg("Using form 1 affinity\n");
 		form1_affinity = 1;
-	else {
-		chosen = of_find_node_by_path("/chosen");
-		if (chosen) {
-			vec5 = of_get_property(chosen,
-					       "ibm,architecture-vec-5", NULL);
-			if (vec5 && (vec5[VEC5_AFFINITY_BYTE] &
-							VEC5_AFFINITY)) {
-				dbg("Using form 1 affinity\n");
-				form1_affinity = 1;
-			}
-
-			of_node_put(chosen);
-		}
 	}
 
 	if (form1_affinity) {
@@ -1268,10 +1257,18 @@ u64 memory_hotplug_max(void)
 
 /* Virtual Processor Home Node (VPHN) support */
 #ifdef CONFIG_PPC_SPLPAR
+struct topology_update_data {
+	struct topology_update_data *next;
+	unsigned int cpu;
+	int old_nid;
+	int new_nid;
+};
+
 static u8 vphn_cpu_change_counts[NR_CPUS][MAX_DISTANCE_REF_POINTS];
 static cpumask_t cpu_associativity_changes_mask;
 static int vphn_enabled;
-static void set_topology_timer(void);
+static int prrn_enabled;
+static void reset_topology_timer(void);
 
 /*
  * Store the current values of the associativity change counters in the
@@ -1307,11 +1304,9 @@ static void setup_cpu_associativity_change_counters(void)
  */
 static int update_cpu_associativity_changes_mask(void)
 {
-	int cpu, nr_cpus = 0;
+	int cpu;
 	cpumask_t *changes = &cpu_associativity_changes_mask;
 
-	cpumask_clear(changes);
-
 	for_each_possible_cpu(cpu) {
 		int i, changed = 0;
 		u8 *counts = vphn_cpu_change_counts[cpu];
@@ -1325,11 +1320,10 @@ static int update_cpu_associativity_changes_mask(void)
 		}
 		if (changed) {
 			cpumask_set_cpu(cpu, changes);
-			nr_cpus++;
 		}
 	}
 
-	return nr_cpus;
+	return cpumask_weight(changes);
 }
 
 /*
@@ -1421,40 +1415,84 @@ static long vphn_get_associativity(unsigned long cpu,
 }
 
 /*
+ * Update the CPU maps and sysfs entries for a single CPU when its NUMA
+ * characteristics change. This function doesn't perform any locking and is
+ * only safe to call from stop_machine().
+ */
+static int update_cpu_topology(void *data)
+{
+	struct topology_update_data *update;
+	unsigned long cpu;
+
+	if (!data)
+		return -EINVAL;
+
+	cpu = get_cpu();
+
+	for (update = data; update; update = update->next) {
+		if (cpu != update->cpu)
+			continue;
+
+		unregister_cpu_under_node(update->cpu, update->old_nid);
+		unmap_cpu_from_node(update->cpu);
+		map_cpu_to_node(update->cpu, update->new_nid);
+		vdso_getcpu_init();
+		register_cpu_under_node(update->cpu, update->new_nid);
+	}
+
+	return 0;
+}
+
+/*
  * Update the node maps and sysfs entries for each cpu whose home node
  * has changed. Returns 1 when the topology has changed, and 0 otherwise.
  */
 int arch_update_cpu_topology(void)
 {
-	int cpu, nid, old_nid, changed = 0;
+	unsigned int cpu, changed = 0;
+	struct topology_update_data *updates, *ud;
 	unsigned int associativity[VPHN_ASSOC_BUFSIZE] = {0};
+	cpumask_t updated_cpus;
 	struct device *dev;
+	int weight, i = 0;
 
-	for_each_cpu(cpu,&cpu_associativity_changes_mask) {
+	weight = cpumask_weight(&cpu_associativity_changes_mask);
+	if (!weight)
+		return 0;
+
+	updates = kzalloc(weight * (sizeof(*updates)), GFP_KERNEL);
+	if (!updates)
+		return 0;
+
+	cpumask_clear(&updated_cpus);
+
+	for_each_cpu(cpu, &cpu_associativity_changes_mask) {
+		ud = &updates[i++];
+		ud->cpu = cpu;
 		vphn_get_associativity(cpu, associativity);
-		nid = associativity_to_nid(associativity);
+		ud->new_nid = associativity_to_nid(associativity);
 
-		if (nid < 0 || !node_online(nid))
-			nid = first_online_node;
+		if (ud->new_nid < 0 || !node_online(ud->new_nid))
+			ud->new_nid = first_online_node;
 
-		old_nid = numa_cpu_lookup_table[cpu];
+		ud->old_nid = numa_cpu_lookup_table[cpu];
+		cpumask_set_cpu(cpu, &updated_cpus);
 
-		/* Disable hotplug while we update the cpu
-		 * masks and sysfs.
-		 */
-		get_online_cpus();
-		unregister_cpu_under_node(cpu, old_nid);
-		unmap_cpu_from_node(cpu);
-		map_cpu_to_node(cpu, nid);
-		register_cpu_under_node(cpu, nid);
-		put_online_cpus();
-
-		dev = get_cpu_device(cpu);
+		if (i < weight)
+			ud->next = &updates[i];
+	}
+
+	stop_machine(update_cpu_topology, &updates[0], &updated_cpus);
+
+	for (ud = &updates[0]; ud; ud = ud->next) {
+		dev = get_cpu_device(ud->cpu);
 		if (dev)
 			kobject_uevent(&dev->kobj, KOBJ_CHANGE);
+		cpumask_clear_cpu(ud->cpu, &cpu_associativity_changes_mask);
 		changed = 1;
 	}
 
+	kfree(updates);
 	return changed;
 }
 
@@ -1471,49 +1509,165 @@ void topology_schedule_update(void)
 
 static void topology_timer_fn(unsigned long ignored)
 {
-	if (!vphn_enabled)
-		return;
-	if (update_cpu_associativity_changes_mask() > 0)
+	if (prrn_enabled && cpumask_weight(&cpu_associativity_changes_mask))
 		topology_schedule_update();
-	set_topology_timer();
+	else if (vphn_enabled) {
+		if (update_cpu_associativity_changes_mask() > 0)
+			topology_schedule_update();
+		reset_topology_timer();
+	}
 }
 static struct timer_list topology_timer =
 	TIMER_INITIALIZER(topology_timer_fn, 0, 0);
 
-static void set_topology_timer(void)
+static void reset_topology_timer(void)
 {
 	topology_timer.data = 0;
 	topology_timer.expires = jiffies + 60 * HZ;
-	add_timer(&topology_timer);
+	mod_timer(&topology_timer, topology_timer.expires);
 }
 
+#ifdef CONFIG_SMP
+
+static void stage_topology_update(int core_id)
+{
+	cpumask_or(&cpu_associativity_changes_mask,
+		&cpu_associativity_changes_mask, cpu_sibling_mask(core_id));
+	reset_topology_timer();
+}
+
+static int dt_update_callback(struct notifier_block *nb,
+				unsigned long action, void *data)
+{
+	struct of_prop_reconfig *update;
+	int rc = NOTIFY_DONE;
+
+	switch (action) {
+	case OF_RECONFIG_UPDATE_PROPERTY:
+		update = (struct of_prop_reconfig *)data;
+		if (!of_prop_cmp(update->dn->type, "cpu") &&
+		    !of_prop_cmp(update->prop->name, "ibm,associativity")) {
+			u32 core_id;
+			of_property_read_u32(update->dn, "reg", &core_id);
+			stage_topology_update(core_id);
+			rc = NOTIFY_OK;
+		}
+		break;
+	}
+
+	return rc;
+}
+
+static struct notifier_block dt_update_nb = {
+	.notifier_call = dt_update_callback,
+};
+
+#endif
+
 /*
- * Start polling for VPHN associativity changes.
+ * Start polling for associativity changes.
  */
 int start_topology_update(void)
 {
 	int rc = 0;
 
-	/* Disabled until races with load balancing are fixed */
-	if (0 && firmware_has_feature(FW_FEATURE_VPHN) &&
-	    get_lppaca()->shared_proc) {
-		vphn_enabled = 1;
-		setup_cpu_associativity_change_counters();
-		init_timer_deferrable(&topology_timer);
-		set_topology_timer();
-		rc = 1;
+	if (firmware_has_feature(FW_FEATURE_PRRN)) {
+		if (!prrn_enabled) {
+			prrn_enabled = 1;
+			vphn_enabled = 0;
+#ifdef CONFIG_SMP
+			rc = of_reconfig_notifier_register(&dt_update_nb);
+#endif
+		}
+	} else if (firmware_has_feature(FW_FEATURE_VPHN) &&
+		   get_lppaca()->shared_proc) {
+		if (!vphn_enabled) {
+			prrn_enabled = 0;
+			vphn_enabled = 1;
+			setup_cpu_associativity_change_counters();
+			init_timer_deferrable(&topology_timer);
+			reset_topology_timer();
+		}
 	}
 
 	return rc;
 }
-__initcall(start_topology_update);
 
 /*
  * Disable polling for VPHN associativity changes.
  */
 int stop_topology_update(void)
 {
-	vphn_enabled = 0;
-	return del_timer_sync(&topology_timer);
+	int rc = 0;
+
+	if (prrn_enabled) {
+		prrn_enabled = 0;
+#ifdef CONFIG_SMP
+		rc = of_reconfig_notifier_unregister(&dt_update_nb);
+#endif
+	} else if (vphn_enabled) {
+		vphn_enabled = 0;
+		rc = del_timer_sync(&topology_timer);
+	}
+
+	return rc;
+}
+
+int prrn_is_enabled(void)
+{
+	return prrn_enabled;
+}
+
+static int topology_read(struct seq_file *file, void *v)
+{
+	if (vphn_enabled || prrn_enabled)
+		seq_puts(file, "on\n");
+	else
+		seq_puts(file, "off\n");
+
+	return 0;
+}
+
+static int topology_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, topology_read, NULL);
+}
+
+static ssize_t topology_write(struct file *file, const char __user *buf,
+			      size_t count, loff_t *off)
+{
+	char kbuf[4]; /* "on" or "off" plus null. */
+	int read_len;
+
+	read_len = count < 3 ? count : 3;
+	if (copy_from_user(kbuf, buf, read_len))
+		return -EINVAL;
+
+	kbuf[read_len] = '\0';
+
+	if (!strncmp(kbuf, "on", 2))
+		start_topology_update();
+	else if (!strncmp(kbuf, "off", 3))
+		stop_topology_update();
+	else
+		return -EINVAL;
+
+	return count;
+}
+
+static const struct file_operations topology_ops = {
+	.read = seq_read,
+	.write = topology_write,
+	.open = topology_open,
+	.release = single_release
+};
+
+static int topology_update_init(void)
+{
+	start_topology_update();
+	proc_create("powerpc/topology_updates", 644, NULL, &topology_ops);
+
+	return 0;
 }
+device_initcall(topology_update_init);
 #endif /* CONFIG_PPC_SPLPAR */