Update Linux to v5.10.109

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.109.tar.xz

Change-Id: I19bca9fc6762d4e63bcf3e4cba88bbe560d9c76c
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index 50d68d2..094a107 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -221,7 +221,8 @@
 	}
 }
 
-/* Returns nid in the range [0..MAX_NUMNODES-1], or -1 if no useful numa
+/*
+ * Returns nid in the range [0..nr_node_ids], or -1 if no useful NUMA
  * info is found.
  */
 static int associativity_to_nid(const __be32 *associativity)
@@ -235,7 +236,7 @@
 		nid = of_read_number(&associativity[min_common_depth], 1);
 
 	/* POWER4 LPAR uses 0xffff as invalid node */
-	if (nid == 0xffff || nid >= MAX_NUMNODES)
+	if (nid == 0xffff || nid >= nr_node_ids)
 		nid = NUMA_NO_NODE;
 
 	if (nid > 0 &&
@@ -429,7 +430,7 @@
  * This is like of_node_to_nid_single() for memory represented in the
  * ibm,dynamic-reconfiguration-memory node.
  */
-static int of_drconf_to_nid_single(struct drmem_lmb *lmb)
+int of_drconf_to_nid_single(struct drmem_lmb *lmb)
 {
 	struct assoc_arrays aa = { .arrays = NULL };
 	int default_nid = NUMA_NO_NODE;
@@ -448,7 +449,7 @@
 		index = lmb->aa_index * aa.array_sz + min_common_depth - 1;
 		nid = of_read_number(&aa.arrays[index], 1);
 
-		if (nid == 0xffff || nid >= MAX_NUMNODES)
+		if (nid == 0xffff || nid >= nr_node_ids)
 			nid = default_nid;
 
 		if (nid > 0) {
@@ -461,25 +462,74 @@
 	return nid;
 }
 
+#ifdef CONFIG_PPC_SPLPAR
+static int vphn_get_nid(long lcpu)
+{
+	__be32 associativity[VPHN_ASSOC_BUFSIZE] = {0};
+	long rc, hwid;
+
+	/*
+	 * On a shared lpar, device tree will not have node associativity.
+	 * At this time lppaca, or its __old_status field may not be
+	 * updated. Hence kernel cannot detect if its on a shared lpar. So
+	 * request an explicit associativity irrespective of whether the
+	 * lpar is shared or dedicated. Use the device tree property as a
+	 * fallback. cpu_to_phys_id is only valid between
+	 * smp_setup_cpu_maps() and smp_setup_pacas().
+	 */
+	if (firmware_has_feature(FW_FEATURE_VPHN)) {
+		if (cpu_to_phys_id)
+			hwid = cpu_to_phys_id[lcpu];
+		else
+			hwid = get_hard_smp_processor_id(lcpu);
+
+		rc = hcall_vphn(hwid, VPHN_FLAG_VCPU, associativity);
+		if (rc == H_SUCCESS)
+			return associativity_to_nid(associativity);
+	}
+
+	return NUMA_NO_NODE;
+}
+#else
+static int vphn_get_nid(long unused)
+{
+	return NUMA_NO_NODE;
+}
+#endif  /* CONFIG_PPC_SPLPAR */
+
 /*
  * Figure out to which domain a cpu belongs and stick it there.
  * Return the id of the domain used.
  */
 static int numa_setup_cpu(unsigned long lcpu)
 {
-	int nid = NUMA_NO_NODE;
 	struct device_node *cpu;
+	int fcpu = cpu_first_thread_sibling(lcpu);
+	int nid = NUMA_NO_NODE;
+
+	if (!cpu_present(lcpu)) {
+		set_cpu_numa_node(lcpu, first_online_node);
+		return first_online_node;
+	}
 
 	/*
 	 * If a valid cpu-to-node mapping is already available, use it
 	 * directly instead of querying the firmware, since it represents
 	 * the most recent mapping notified to us by the platform (eg: VPHN).
+	 * Since cpu_to_node binding remains the same for all threads in the
+	 * core. If a valid cpu-to-node mapping is already available, for
+	 * the first thread in the core, use it.
 	 */
-	if ((nid = numa_cpu_lookup_table[lcpu]) >= 0) {
+	nid = numa_cpu_lookup_table[fcpu];
+	if (nid >= 0) {
 		map_cpu_to_node(lcpu, nid);
 		return nid;
 	}
 
+	nid = vphn_get_nid(lcpu);
+	if (nid != NUMA_NO_NODE)
+		goto out_present;
+
 	cpu = of_get_cpu_node(lcpu, NULL);
 
 	if (!cpu) {
@@ -491,13 +541,26 @@
 	}
 
 	nid = of_node_to_nid_single(cpu);
+	of_node_put(cpu);
 
 out_present:
 	if (nid < 0 || !node_possible(nid))
 		nid = first_online_node;
 
+	/*
+	 * Update for the first thread of the core. All threads of a core
+	 * have to be part of the same node. This not only avoids querying
+	 * for every other thread in the core, but always avoids a case
+	 * where virtual node associativity change causes subsequent threads
+	 * of a core to be associated with different nid. However if first
+	 * thread is already online, expect it to have a valid mapping.
+	 */
+	if (fcpu != lcpu) {
+		WARN_ON(cpu_online(fcpu));
+		map_cpu_to_node(fcpu, nid);
+	}
+
 	map_cpu_to_node(lcpu, nid);
-	of_node_put(cpu);
 out:
 	return nid;
 }
@@ -587,8 +650,9 @@
  * Extract NUMA information from the ibm,dynamic-reconfiguration-memory
  * node.  This assumes n_mem_{addr,size}_cells have been set.
  */
-static void __init numa_setup_drmem_lmb(struct drmem_lmb *lmb,
-					const __be32 **usm)
+static int __init numa_setup_drmem_lmb(struct drmem_lmb *lmb,
+					const __be32 **usm,
+					void *data)
 {
 	unsigned int ranges, is_kexec_kdump = 0;
 	unsigned long base, size, sz;
@@ -600,7 +664,7 @@
 	 */
 	if ((lmb->flags & DRCONF_MEM_RESERVED)
 	    || !(lmb->flags & DRCONF_MEM_ASSIGNED))
-		return;
+		return 0;
 
 	if (*usm)
 		is_kexec_kdump = 1;
@@ -612,7 +676,7 @@
 	if (is_kexec_kdump) {
 		ranges = read_usm_ranges(usm);
 		if (!ranges) /* there are no (base, size) duple */
-			return;
+			return 0;
 	}
 
 	do {
@@ -629,6 +693,8 @@
 		if (sz)
 			memblock_set_node(base, sz, &memblock.memory, nid);
 	} while (--ranges);
+
+	return 0;
 }
 
 static int __init parse_numa_properties(void)
@@ -662,20 +728,20 @@
 	 */
 	for_each_present_cpu(i) {
 		struct device_node *cpu;
-		int nid;
-
-		cpu = of_get_cpu_node(i, NULL);
-		BUG_ON(!cpu);
-		nid = of_node_to_nid_single(cpu);
-		of_node_put(cpu);
+		int nid = vphn_get_nid(i);
 
 		/*
 		 * Don't fall back to default_nid yet -- we will plug
 		 * cpus into nodes once the memory scan has discovered
 		 * the topology.
 		 */
-		if (nid < 0)
-			continue;
+		if (nid == NUMA_NO_NODE) {
+			cpu = of_get_cpu_node(i, NULL);
+			BUG_ON(!cpu);
+			nid = of_node_to_nid_single(cpu);
+			of_node_put(cpu);
+		}
+
 		node_set_online(nid);
 	}
 
@@ -730,7 +796,7 @@
 	 */
 	memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
 	if (memory) {
-		walk_drmem_lmbs(memory, numa_setup_drmem_lmb);
+		walk_drmem_lmbs(memory, NULL, numa_setup_drmem_lmb);
 		of_node_put(memory);
 	}
 
@@ -743,17 +809,14 @@
 	unsigned long total_ram = memblock_phys_mem_size();
 	unsigned long start_pfn, end_pfn;
 	unsigned int nid = 0;
-	struct memblock_region *reg;
+	int i;
 
 	printk(KERN_DEBUG "Top of RAM: 0x%lx, Total RAM: 0x%lx\n",
 	       top_of_ram, total_ram);
 	printk(KERN_DEBUG "Memory hole size: %ldMB\n",
 	       (top_of_ram - total_ram) >> 20);
 
-	for_each_memblock(memory, reg) {
-		start_pfn = memblock_region_memory_base_pfn(reg);
-		end_pfn = memblock_region_memory_end_pfn(reg);
-
+	for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, NULL) {
 		fake_numa_create_new_node(end_pfn, &nid);
 		memblock_set_node(PFN_PHYS(start_pfn),
 				  PFN_PHYS(end_pfn - start_pfn),
@@ -830,7 +893,9 @@
 static void __init find_possible_nodes(void)
 {
 	struct device_node *rtas;
-	u32 numnodes, i;
+	const __be32 *domains = NULL;
+	int prop_length, max_nodes;
+	u32 i;
 
 	if (!numa_enabled)
 		return;
@@ -839,16 +904,38 @@
 	if (!rtas)
 		return;
 
-	if (of_property_read_u32_index(rtas,
-				"ibm,max-associativity-domains",
-				min_common_depth, &numnodes))
-		goto out;
+	/*
+	 * ibm,current-associativity-domains is a fairly recent property. If
+	 * it doesn't exist, then fallback on ibm,max-associativity-domains.
+	 * Current denotes what the platform can support compared to max
+	 * which denotes what the Hypervisor can support.
+	 *
+	 * If the LPAR is migratable, new nodes might be activated after a LPM,
+	 * so we should consider the max number in that case.
+	 */
+	if (!of_get_property(of_root, "ibm,migratable-partition", NULL))
+		domains = of_get_property(rtas,
+					  "ibm,current-associativity-domains",
+					  &prop_length);
+	if (!domains) {
+		domains = of_get_property(rtas, "ibm,max-associativity-domains",
+					&prop_length);
+		if (!domains)
+			goto out;
+	}
 
-	for (i = 0; i < numnodes; i++) {
+	max_nodes = of_read_number(&domains[min_common_depth], 1);
+	pr_info("Partition configured for %d NUMA nodes.\n", max_nodes);
+
+	for (i = 0; i < max_nodes; i++) {
 		if (!node_possible(i))
 			node_set(i, node_possible_map);
 	}
 
+	prop_length /= sizeof(int);
+	if (prop_length > min_common_depth + 2)
+		coregroup_enabled = 1;
+
 out:
 	of_node_put(rtas);
 }
@@ -857,6 +944,16 @@
 {
 	int cpu;
 
+	/*
+	 * Linux/mm assumes node 0 to be online at boot. However this is not
+	 * true on PowerPC, where node 0 is similar to any other node, it
+	 * could be cpuless, memoryless node. So force node 0 to be offline
+	 * for now. This will prevent cpuless, memoryless node 0 showing up
+	 * unnecessarily as online. If a node has cpus or memory that need
+	 * to be online, then node will anyway be marked online.
+	 */
+	node_set_offline(0);
+
 	if (parse_numa_properties())
 		setup_nonnuma();
 
@@ -874,8 +971,17 @@
 
 	reset_numa_cpu_lookup_table();
 
-	for_each_present_cpu(cpu)
+	for_each_possible_cpu(cpu) {
+		/*
+		 * Powerpc with CONFIG_NUMA always used to have a node 0,
+		 * even if it was memoryless or cpuless. For all cpus that
+		 * are possible but not present, cpu_to_node() would point
+		 * to node 0. To remove a cpuless, memoryless dummy node,
+		 * powerpc need to make sure all possible but not present
+		 * cpu_to_node are set to a proper node.
+		 */
 		numa_setup_cpu(cpu);
+	}
 }
 
 void __init initmem_init(void)
@@ -892,7 +998,6 @@
 
 		get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
 		setup_node_data(nid, start_pfn, end_pfn);
-		sparse_memory_present_with_active_regions(nid);
 	}
 
 	sparse_init();
@@ -927,28 +1032,6 @@
 }
 early_param("numa", early_numa);
 
-/*
- * 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, "on")) {
-		pr_warn("Caution: enabling topology updates\n");
-		topology_updates_enabled = true;
-	}
-
-	return 0;
-}
-early_param("topology_updates", early_topology_updates);
-
 #ifdef CONFIG_MEMORY_HOTPLUG
 /*
  * Find the node associated with a hot added memory section for
@@ -1087,98 +1170,9 @@
 
 /* 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;
-};
-
-#define TOPOLOGY_DEF_TIMER_SECS	60
-
-static u8 vphn_cpu_change_counts[NR_CPUS][MAX_DISTANCE_REF_POINTS];
-static cpumask_t cpu_associativity_changes_mask;
-static int vphn_enabled;
-static int prrn_enabled;
-static void reset_topology_timer(void);
-static int topology_timer_secs = 1;
 static int topology_inited;
 
 /*
- * Change polling interval for associativity changes.
- */
-int timed_topology_update(int nsecs)
-{
-	if (vphn_enabled) {
-		if (nsecs > 0)
-			topology_timer_secs = nsecs;
-		else
-			topology_timer_secs = TOPOLOGY_DEF_TIMER_SECS;
-
-		reset_topology_timer();
-	}
-
-	return 0;
-}
-
-/*
- * Store the current values of the associativity change counters in the
- * hypervisor.
- */
-static void setup_cpu_associativity_change_counters(void)
-{
-	int cpu;
-
-	/* The VPHN feature supports a maximum of 8 reference points */
-	BUILD_BUG_ON(MAX_DISTANCE_REF_POINTS > 8);
-
-	for_each_possible_cpu(cpu) {
-		int i;
-		u8 *counts = vphn_cpu_change_counts[cpu];
-		volatile u8 *hypervisor_counts = lppaca_of(cpu).vphn_assoc_counts;
-
-		for (i = 0; i < distance_ref_points_depth; i++)
-			counts[i] = hypervisor_counts[i];
-	}
-}
-
-/*
- * The hypervisor maintains a set of 8 associativity change counters in
- * the VPA of each cpu that correspond to the associativity levels in the
- * ibm,associativity-reference-points property. When an associativity
- * level changes, the corresponding counter is incremented.
- *
- * Set a bit in cpu_associativity_changes_mask for each cpu whose home
- * node associativity levels have changed.
- *
- * Returns the number of cpus with unhandled associativity changes.
- */
-static int update_cpu_associativity_changes_mask(void)
-{
-	int cpu;
-	cpumask_t *changes = &cpu_associativity_changes_mask;
-
-	for_each_possible_cpu(cpu) {
-		int i, changed = 0;
-		u8 *counts = vphn_cpu_change_counts[cpu];
-		volatile u8 *hypervisor_counts = lppaca_of(cpu).vphn_assoc_counts;
-
-		for (i = 0; i < distance_ref_points_depth; i++) {
-			if (hypervisor_counts[i] != counts[i]) {
-				counts[i] = hypervisor_counts[i];
-				changed = 1;
-			}
-		}
-		if (changed) {
-			cpumask_or(changes, changes, cpu_sibling_mask(cpu));
-			cpu = cpu_last_thread_sibling(cpu);
-		}
-	}
-
-	return cpumask_weight(changes);
-}
-
-/*
  * Retrieve the new associativity information for a virtual processor's
  * home node.
  */
@@ -1191,23 +1185,27 @@
 				VPHN_FLAG_VCPU, associativity);
 
 	switch (rc) {
-	case H_FUNCTION:
-		printk_once(KERN_INFO
-			"VPHN is not supported. Disabling polling...\n");
-		stop_topology_update();
-		break;
-	case H_HARDWARE:
-		printk(KERN_ERR
-			"hcall_vphn() experienced a hardware fault "
-			"preventing VPHN. Disabling polling...\n");
-		stop_topology_update();
-		break;
 	case H_SUCCESS:
 		dbg("VPHN hcall succeeded. Reset polling...\n");
-		timed_topology_update(0);
+		goto out;
+
+	case H_FUNCTION:
+		pr_err_ratelimited("VPHN unsupported. Disabling polling...\n");
+		break;
+	case H_HARDWARE:
+		pr_err_ratelimited("hcall_vphn() experienced a hardware fault "
+			"preventing VPHN. Disabling polling...\n");
+		break;
+	case H_PARAMETER:
+		pr_err_ratelimited("hcall_vphn() was passed an invalid parameter. "
+			"Disabling polling...\n");
+		break;
+	default:
+		pr_err_ratelimited("hcall_vphn() returned %ld. Disabling polling...\n"
+			, rc);
 		break;
 	}
-
+out:
 	return rc;
 }
 
@@ -1250,389 +1248,33 @@
 	return new_nid;
 }
 
-/*
- * 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)
+int cpu_to_coregroup_id(int cpu)
 {
-	struct topology_update_data *update;
-	unsigned long cpu;
+	__be32 associativity[VPHN_ASSOC_BUFSIZE] = {0};
+	int index;
 
-	if (!data)
-		return -EINVAL;
+	if (cpu < 0 || cpu > nr_cpu_ids)
+		return -1;
 
-	cpu = smp_processor_id();
-
-	for (update = data; update; update = update->next) {
-		int new_nid = update->new_nid;
-		if (cpu != update->cpu)
-			continue;
-
-		unmap_cpu_from_node(cpu);
-		map_cpu_to_node(cpu, new_nid);
-		set_cpu_numa_node(cpu, new_nid);
-		set_cpu_numa_mem(cpu, local_memory_node(new_nid));
-		vdso_getcpu_init();
-	}
-
-	return 0;
-}
-
-static int update_lookup_table(void *data)
-{
-	struct topology_update_data *update;
-
-	if (!data)
-		return -EINVAL;
-
-	/*
-	 * Upon topology update, the numa-cpu lookup table needs to be updated
-	 * for all threads in the core, including offline CPUs, to ensure that
-	 * future hotplug operations respect the cpu-to-node associativity
-	 * properly.
-	 */
-	for (update = data; update; update = update->next) {
-		int nid, base, j;
-
-		nid = update->new_nid;
-		base = cpu_first_thread_sibling(update->cpu);
-
-		for (j = 0; j < threads_per_core; j++) {
-			update_numa_cpu_lookup_table(base + j, 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.
- *
- * cpus_locked says whether we already hold cpu_hotplug_lock.
- */
-int numa_update_cpu_topology(bool cpus_locked)
-{
-	unsigned int cpu, sibling, changed = 0;
-	struct topology_update_data *updates, *ud;
-	cpumask_t updated_cpus;
-	struct device *dev;
-	int weight, new_nid, i = 0;
-
-	if (!prrn_enabled && !vphn_enabled && topology_inited)
-		return 0;
-
-	weight = cpumask_weight(&cpu_associativity_changes_mask);
-	if (!weight)
-		return 0;
-
-	updates = kcalloc(weight, sizeof(*updates), GFP_KERNEL);
-	if (!updates)
-		return 0;
-
-	cpumask_clear(&updated_cpus);
-
-	for_each_cpu(cpu, &cpu_associativity_changes_mask) {
-		/*
-		 * If siblings aren't flagged for changes, updates list
-		 * will be too short. Skip on this update and set for next
-		 * update.
-		 */
-		if (!cpumask_subset(cpu_sibling_mask(cpu),
-					&cpu_associativity_changes_mask)) {
-			pr_info("Sibling bits not set for associativity "
-					"change, cpu%d\n", cpu);
-			cpumask_or(&cpu_associativity_changes_mask,
-					&cpu_associativity_changes_mask,
-					cpu_sibling_mask(cpu));
-			cpu = cpu_last_thread_sibling(cpu);
-			continue;
-		}
-
-		new_nid = find_and_online_cpu_nid(cpu);
-
-		if (new_nid == numa_cpu_lookup_table[cpu]) {
-			cpumask_andnot(&cpu_associativity_changes_mask,
-					&cpu_associativity_changes_mask,
-					cpu_sibling_mask(cpu));
-			dbg("Assoc chg gives same node %d for cpu%d\n",
-					new_nid, cpu);
-			cpu = cpu_last_thread_sibling(cpu);
-			continue;
-		}
-
-		for_each_cpu(sibling, cpu_sibling_mask(cpu)) {
-			ud = &updates[i++];
-			ud->next = &updates[i];
-			ud->cpu = sibling;
-			ud->new_nid = new_nid;
-			ud->old_nid = numa_cpu_lookup_table[sibling];
-			cpumask_set_cpu(sibling, &updated_cpus);
-		}
-		cpu = cpu_last_thread_sibling(cpu);
-	}
-
-	/*
-	 * Prevent processing of 'updates' from overflowing array
-	 * where last entry filled in a 'next' pointer.
-	 */
-	if (i)
-		updates[i-1].next = NULL;
-
-	pr_debug("Topology update for the following CPUs:\n");
-	if (cpumask_weight(&updated_cpus)) {
-		for (ud = &updates[0]; ud; ud = ud->next) {
-			pr_debug("cpu %d moving from node %d "
-					  "to %d\n", ud->cpu,
-					  ud->old_nid, ud->new_nid);
-		}
-	}
-
-	/*
-	 * In cases where we have nothing to update (because the updates list
-	 * is too short or because the new topology is same as the old one),
-	 * skip invoking update_cpu_topology() via stop-machine(). This is
-	 * necessary (and not just a fast-path optimization) since stop-machine
-	 * can end up electing a random CPU to run update_cpu_topology(), and
-	 * thus trick us into setting up incorrect cpu-node mappings (since
-	 * 'updates' is kzalloc()'ed).
-	 *
-	 * And for the similar reason, we will skip all the following updating.
-	 */
-	if (!cpumask_weight(&updated_cpus))
+	if (!coregroup_enabled)
 		goto out;
 
-	if (cpus_locked)
-		stop_machine_cpuslocked(update_cpu_topology, &updates[0],
-					&updated_cpus);
-	else
-		stop_machine(update_cpu_topology, &updates[0], &updated_cpus);
+	if (!firmware_has_feature(FW_FEATURE_VPHN))
+		goto out;
 
-	/*
-	 * Update the numa-cpu lookup table with the new mappings, even for
-	 * offline CPUs. It is best to perform this update from the stop-
-	 * machine context.
-	 */
-	if (cpus_locked)
-		stop_machine_cpuslocked(update_lookup_table, &updates[0],
-					cpumask_of(raw_smp_processor_id()));
-	else
-		stop_machine(update_lookup_table, &updates[0],
-			     cpumask_of(raw_smp_processor_id()));
+	if (vphn_get_associativity(cpu, associativity))
+		goto out;
 
-	for (ud = &updates[0]; ud; ud = ud->next) {
-		unregister_cpu_under_node(ud->cpu, ud->old_nid);
-		register_cpu_under_node(ud->cpu, ud->new_nid);
-
-		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;
-	}
+	index = of_read_number(associativity, 1);
+	if (index > min_common_depth + 1)
+		return of_read_number(&associativity[index - 1], 1);
 
 out:
-	kfree(updates);
-	return changed;
+	return cpu_to_core_id(cpu);
 }
 
-int arch_update_cpu_topology(void)
-{
-	return numa_update_cpu_topology(true);
-}
-
-static void topology_work_fn(struct work_struct *work)
-{
-	rebuild_sched_domains();
-}
-static DECLARE_WORK(topology_work, topology_work_fn);
-
-static void topology_schedule_update(void)
-{
-	schedule_work(&topology_work);
-}
-
-static void topology_timer_fn(struct timer_list *unused)
-{
-	if (prrn_enabled && cpumask_weight(&cpu_associativity_changes_mask))
-		topology_schedule_update();
-	else if (vphn_enabled) {
-		if (update_cpu_associativity_changes_mask() > 0)
-			topology_schedule_update();
-		reset_topology_timer();
-	}
-}
-static struct timer_list topology_timer;
-
-static void reset_topology_timer(void)
-{
-	if (vphn_enabled)
-		mod_timer(&topology_timer, jiffies + topology_timer_secs * HZ);
-}
-
-#ifdef CONFIG_SMP
-
-static int dt_update_callback(struct notifier_block *nb,
-				unsigned long action, void *data)
-{
-	struct of_reconfig_data *update = data;
-	int rc = NOTIFY_DONE;
-
-	switch (action) {
-	case OF_RECONFIG_UPDATE_PROPERTY:
-		if (of_node_is_type(update->dn, "cpu") &&
-		    !of_prop_cmp(update->prop->name, "ibm,associativity")) {
-			u32 core_id;
-			of_property_read_u32(update->dn, "reg", &core_id);
-			rc = dlpar_cpu_readd(core_id);
-			rc = NOTIFY_OK;
-		}
-		break;
-	}
-
-	return rc;
-}
-
-static struct notifier_block dt_update_nb = {
-	.notifier_call = dt_update_callback,
-};
-
-#endif
-
-/*
- * Start polling for associativity changes.
- */
-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;
-#ifdef CONFIG_SMP
-			rc = of_reconfig_notifier_register(&dt_update_nb);
-#endif
-		}
-	}
-	if (firmware_has_feature(FW_FEATURE_VPHN) &&
-		   lppaca_shared_proc(get_lppaca())) {
-		if (!vphn_enabled) {
-			vphn_enabled = 1;
-			setup_cpu_associativity_change_counters();
-			timer_setup(&topology_timer, topology_timer_fn,
-				    TIMER_DEFERRABLE);
-			reset_topology_timer();
-		}
-	}
-
-	pr_info("Starting topology update%s%s\n",
-		(prrn_enabled ? " prrn_enabled" : ""),
-		(vphn_enabled ? " vphn_enabled" : ""));
-
-	return rc;
-}
-
-/*
- * Disable polling for VPHN associativity changes.
- */
-int stop_topology_update(void)
-{
-	int rc = 0;
-
-	if (!topology_updates_enabled)
-		return 0;
-
-	if (prrn_enabled) {
-		prrn_enabled = 0;
-#ifdef CONFIG_SMP
-		rc = of_reconfig_notifier_unregister(&dt_update_nb);
-#endif
-	}
-	if (vphn_enabled) {
-		vphn_enabled = 0;
-		rc = del_timer_sync(&topology_timer);
-	}
-
-	pr_info("Stopping topology update\n");
-
-	return rc;
-}
-
-int prrn_is_enabled(void)
-{
-	return prrn_enabled;
-}
-
-void __init shared_proc_topology_init(void)
-{
-	if (lppaca_shared_proc(get_lppaca())) {
-		bitmap_fill(cpumask_bits(&cpu_associativity_changes_mask),
-			    nr_cpumask_bits);
-		numa_update_cpu_topology(false);
-	}
-}
-
-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)) {
-		topology_updates_enabled = true;
-		start_topology_update();
-	} else if (!strncmp(kbuf, "off", 3)) {
-		stop_topology_update();
-		topology_updates_enabled = false;
-	} 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();
-
-	if (vphn_enabled)
-		topology_schedule_update();
-
-	if (!proc_create("powerpc/topology_updates", 0644, NULL, &topology_ops))
-		return -ENOMEM;
-
 	topology_inited = 1;
 	return 0;
 }