arch/s390/kernel/topology.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  *    Copyright IBM Corp. 2007, 2011
  *    Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
  */

 #define KMSG_COMPONENT "cpu"
 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt

 #include <linux/workqueue.h>
 #include <linux/bootmem.h>
 #include <linux/uaccess.h>
 #include <linux/sysctl.h>
 #include <linux/cpuset.h>
 #include <linux/device.h>
 #include <linux/export.h>
 #include <linux/kernel.h>
 #include <linux/sched.h>
 #include <linux/sched/topology.h>
 #include <linux/delay.h>
 #include <linux/init.h>
 #include <linux/slab.h>
 #include <linux/cpu.h>
 #include <linux/smp.h>
 #include <linux/mm.h>
 #include <linux/nodemask.h>
 #include <linux/node.h>
 #include <asm/sysinfo.h>
 #include <asm/numa.h>

 #define PTF_HORIZONTAL	(0UL)
 #define PTF_VERTICAL	(1UL)
 #define PTF_CHECK	(2UL)

 enum {
 	TOPOLOGY_MODE_HW,
 	TOPOLOGY_MODE_SINGLE,
 	TOPOLOGY_MODE_PACKAGE,
 	TOPOLOGY_MODE_UNINITIALIZED
 };

 struct mask_info {
 	struct mask_info *next;
 	unsigned char id;
 	cpumask_t mask;
 };

 static int topology_mode = TOPOLOGY_MODE_UNINITIALIZED;
 static void set_topology_timer(void);
 static void topology_work_fn(struct work_struct *work);
 static struct sysinfo_15_1_x *tl_info;

 static DECLARE_WORK(topology_work, topology_work_fn);

 /*
  * Socket/Book linked lists and cpu_topology updates are
  * protected by "sched_domains_mutex".
  */
 static struct mask_info socket_info;
 static struct mask_info book_info;
 static struct mask_info drawer_info;

 struct cpu_topology_s390 cpu_topology[NR_CPUS];
 EXPORT_SYMBOL_GPL(cpu_topology);

 cpumask_t cpus_with_topology;

 static cpumask_t cpu_group_map(struct mask_info *info, unsigned int cpu)
 {
 	cpumask_t mask;

 	cpumask_copy(&mask, cpumask_of(cpu));
 	switch (topology_mode) {
 	case TOPOLOGY_MODE_HW:
 		while (info) {
 			if (cpumask_test_cpu(cpu, &info->mask)) {
 				mask = info->mask;
 				break;
 			}
 			info = info->next;
 		}
 		if (cpumask_empty(&mask))
 			cpumask_copy(&mask, cpumask_of(cpu));
 		break;
 	case TOPOLOGY_MODE_PACKAGE:
 		cpumask_copy(&mask, cpu_present_mask);
 		break;
 	default:
 		/* fallthrough */
 	case TOPOLOGY_MODE_SINGLE:
 		cpumask_copy(&mask, cpumask_of(cpu));
 		break;
 	}
 	return mask;
 }

 static cpumask_t cpu_thread_map(unsigned int cpu)
 {
 	cpumask_t mask;
 	int i;

 	cpumask_copy(&mask, cpumask_of(cpu));
 	if (topology_mode != TOPOLOGY_MODE_HW)
 		return mask;
 	cpu -= cpu % (smp_cpu_mtid + 1);
 	for (i = 0; i <= smp_cpu_mtid; i++)
 		if (cpu_present(cpu + i))
 			cpumask_set_cpu(cpu + i, &mask);
 	return mask;
 }

 #define TOPOLOGY_CORE_BITS	64

 static void add_cpus_to_mask(struct topology_core *tl_core,
 			     struct mask_info *drawer,
 			     struct mask_info *book,
 			     struct mask_info *socket)
 {
 	struct cpu_topology_s390 *topo;
 	unsigned int core;

 	for_each_set_bit(core, &tl_core->mask, TOPOLOGY_CORE_BITS) {
 		unsigned int rcore;
 		int lcpu, i;

 		rcore = TOPOLOGY_CORE_BITS - 1 - core + tl_core->origin;
 		lcpu = smp_find_processor_id(rcore << smp_cpu_mt_shift);
 		if (lcpu < 0)
 			continue;
 		for (i = 0; i <= smp_cpu_mtid; i++) {
 			topo = &cpu_topology[lcpu + i];
 			topo->drawer_id = drawer->id;
 			topo->book_id = book->id;
 			topo->socket_id = socket->id;
 			topo->core_id = rcore;
 			topo->thread_id = lcpu + i;
 			topo->dedicated = tl_core->d;
 			cpumask_set_cpu(lcpu + i, &drawer->mask);
 			cpumask_set_cpu(lcpu + i, &book->mask);
 			cpumask_set_cpu(lcpu + i, &socket->mask);
 			cpumask_set_cpu(lcpu + i, &cpus_with_topology);
 			smp_cpu_set_polarization(lcpu + i, tl_core->pp);
 		}
 	}
 }

 static void clear_masks(void)
 {
 	struct mask_info *info;

 	info = &socket_info;
 	while (info) {
 		cpumask_clear(&info->mask);
 		info = info->next;
 	}
 	info = &book_info;
 	while (info) {
 		cpumask_clear(&info->mask);
 		info = info->next;
 	}
 	info = &drawer_info;
 	while (info) {
 		cpumask_clear(&info->mask);
 		info = info->next;
 	}
 }

 static union topology_entry *next_tle(union topology_entry *tle)
 {
 	if (!tle->nl)
 		return (union topology_entry *)((struct topology_core *)tle + 1);
 	return (union topology_entry *)((struct topology_container *)tle + 1);
 }

 static void tl_to_masks(struct sysinfo_15_1_x *info)
 {
 	struct mask_info *socket = &socket_info;
 	struct mask_info *book = &book_info;
 	struct mask_info *drawer = &drawer_info;
 	union topology_entry *tle, *end;

 	clear_masks();
 	tle = info->tle;
 	end = (union topology_entry *)((unsigned long)info + info->length);
 	while (tle < end) {
 		switch (tle->nl) {
 		case 3:
 			drawer = drawer->next;
 			drawer->id = tle->container.id;
 			break;
 		case 2:
 			book = book->next;
 			book->id = tle->container.id;
 			break;
 		case 1:
 			socket = socket->next;
 			socket->id = tle->container.id;
 			break;
 		case 0:
 			add_cpus_to_mask(&tle->cpu, drawer, book, socket);
 			break;
 		default:
 			clear_masks();
 			return;
 		}
 		tle = next_tle(tle);
 	}
 }

 static void topology_update_polarization_simple(void)
 {
 	int cpu;

 	for_each_possible_cpu(cpu)
 		smp_cpu_set_polarization(cpu, POLARIZATION_HRZ);
 }

 static int ptf(unsigned long fc)
 {
 	int rc;

 	asm volatile(
 		"	.insn	rre,0xb9a20000,%1,%1\n"
 		"	ipm	%0\n"
 		"	srl	%0,28\n"
 		: "=d" (rc)
 		: "d" (fc)  : "cc");
 	return rc;
 }

 int topology_set_cpu_management(int fc)
 {
 	int cpu, rc;

 	if (!MACHINE_HAS_TOPOLOGY)
 		return -EOPNOTSUPP;
 	if (fc)
 		rc = ptf(PTF_VERTICAL);
 	else
 		rc = ptf(PTF_HORIZONTAL);
 	if (rc)
 		return -EBUSY;
 	for_each_possible_cpu(cpu)
 		smp_cpu_set_polarization(cpu, POLARIZATION_UNKNOWN);
 	return rc;
 }

 static void update_cpu_masks(void)
 {
 	struct cpu_topology_s390 *topo;
 	int cpu, id;

 	for_each_possible_cpu(cpu) {
 		topo = &cpu_topology[cpu];
 		topo->thread_mask = cpu_thread_map(cpu);
 		topo->core_mask = cpu_group_map(&socket_info, cpu);
 		topo->book_mask = cpu_group_map(&book_info, cpu);
 		topo->drawer_mask = cpu_group_map(&drawer_info, cpu);
 		if (topology_mode != TOPOLOGY_MODE_HW) {
 			id = topology_mode == TOPOLOGY_MODE_PACKAGE ? 0 : cpu;
 			topo->thread_id = cpu;
 			topo->core_id = cpu;
 			topo->socket_id = id;
 			topo->book_id = id;
 			topo->drawer_id = id;
 			if (cpu_present(cpu))
 				cpumask_set_cpu(cpu, &cpus_with_topology);
 		}
 	}
 	numa_update_cpu_topology();
 }

 void store_topology(struct sysinfo_15_1_x *info)
 {
 	stsi(info, 15, 1, topology_mnest_limit());
 }

 static void __arch_update_dedicated_flag(void *arg)
 {
 	if (topology_cpu_dedicated(smp_processor_id()))
 		set_cpu_flag(CIF_DEDICATED_CPU);
 	else
 		clear_cpu_flag(CIF_DEDICATED_CPU);
 }

 static int __arch_update_cpu_topology(void)
 {
 	struct sysinfo_15_1_x *info = tl_info;
 	int rc = 0;

 	mutex_lock(&smp_cpu_state_mutex);
 	cpumask_clear(&cpus_with_topology);
 	if (MACHINE_HAS_TOPOLOGY) {
 		rc = 1;
 		store_topology(info);
 		tl_to_masks(info);
 	}
 	update_cpu_masks();
 	if (!MACHINE_HAS_TOPOLOGY)
 		topology_update_polarization_simple();
 	mutex_unlock(&smp_cpu_state_mutex);
 	return rc;
 }

 int arch_update_cpu_topology(void)
 {
 	struct device *dev;
 	int cpu, rc;

 	rc = __arch_update_cpu_topology();
 	on_each_cpu(__arch_update_dedicated_flag, NULL, 0);
 	for_each_online_cpu(cpu) {
 		dev = get_cpu_device(cpu);
 		kobject_uevent(&dev->kobj, KOBJ_CHANGE);
 	}
 	return rc;
 }

 static void topology_work_fn(struct work_struct *work)
 {
 	rebuild_sched_domains();
 }

 void topology_schedule_update(void)
 {
 	schedule_work(&topology_work);
 }

 static void topology_flush_work(void)
 {
 	flush_work(&topology_work);
 }

 static void topology_timer_fn(struct timer_list *unused)
 {
 	if (ptf(PTF_CHECK))
 		topology_schedule_update();
 	set_topology_timer();
 }

 static struct timer_list topology_timer;

 static atomic_t topology_poll = ATOMIC_INIT(0);

 static void set_topology_timer(void)
 {
 	if (atomic_add_unless(&topology_poll, -1, 0))
 		mod_timer(&topology_timer, jiffies + HZ / 10);
 	else
 		mod_timer(&topology_timer, jiffies + HZ * 60);
 }

 void topology_expect_change(void)
 {
 	if (!MACHINE_HAS_TOPOLOGY)
 		return;
 	/* This is racy, but it doesn't matter since it is just a heuristic.
 	 * Worst case is that we poll in a higher frequency for a bit longer.
 	 */
 	if (atomic_read(&topology_poll) > 60)
 		return;
 	atomic_add(60, &topology_poll);
 	set_topology_timer();
 }

 static int cpu_management;

 static ssize_t dispatching_show(struct device *dev,
 				struct device_attribute *attr,
 				char *buf)
 {
 	ssize_t count;

 	mutex_lock(&smp_cpu_state_mutex);
 	count = sprintf(buf, "%d\n", cpu_management);
 	mutex_unlock(&smp_cpu_state_mutex);
 	return count;
 }

 static ssize_t dispatching_store(struct device *dev,
 				 struct device_attribute *attr,
 				 const char *buf,
 				 size_t count)
 {
 	int val, rc;
 	char delim;

 	if (sscanf(buf, "%d %c", &val, &delim) != 1)
 		return -EINVAL;
 	if (val != 0 && val != 1)
 		return -EINVAL;
 	rc = 0;
 	get_online_cpus();
 	mutex_lock(&smp_cpu_state_mutex);
 	if (cpu_management == val)
 		goto out;
 	rc = topology_set_cpu_management(val);
 	if (rc)
 		goto out;
 	cpu_management = val;
 	topology_expect_change();
 out:
 	mutex_unlock(&smp_cpu_state_mutex);
 	put_online_cpus();
 	return rc ? rc : count;
 }
 static DEVICE_ATTR_RW(dispatching);

 static ssize_t cpu_polarization_show(struct device *dev,
 				     struct device_attribute *attr, char *buf)
 {
 	int cpu = dev->id;
 	ssize_t count;

 	mutex_lock(&smp_cpu_state_mutex);
 	switch (smp_cpu_get_polarization(cpu)) {
 	case POLARIZATION_HRZ:
 		count = sprintf(buf, "horizontal\n");
 		break;
 	case POLARIZATION_VL:
 		count = sprintf(buf, "vertical:low\n");
 		break;
 	case POLARIZATION_VM:
 		count = sprintf(buf, "vertical:medium\n");
 		break;
 	case POLARIZATION_VH:
 		count = sprintf(buf, "vertical:high\n");
 		break;
 	default:
 		count = sprintf(buf, "unknown\n");
 		break;
 	}
 	mutex_unlock(&smp_cpu_state_mutex);
 	return count;
 }
 static DEVICE_ATTR(polarization, 0444, cpu_polarization_show, NULL);

 static struct attribute *topology_cpu_attrs[] = {
 	&dev_attr_polarization.attr,
 	NULL,
 };

 static struct attribute_group topology_cpu_attr_group = {
 	.attrs = topology_cpu_attrs,
 };

 static ssize_t cpu_dedicated_show(struct device *dev,
 				  struct device_attribute *attr, char *buf)
 {
 	int cpu = dev->id;
 	ssize_t count;

 	mutex_lock(&smp_cpu_state_mutex);
 	count = sprintf(buf, "%d\n", topology_cpu_dedicated(cpu));
 	mutex_unlock(&smp_cpu_state_mutex);
 	return count;
 }
 static DEVICE_ATTR(dedicated, 0444, cpu_dedicated_show, NULL);

 static struct attribute *topology_extra_cpu_attrs[] = {
 	&dev_attr_dedicated.attr,
 	NULL,
 };

 static struct attribute_group topology_extra_cpu_attr_group = {
 	.attrs = topology_extra_cpu_attrs,
 };

 int topology_cpu_init(struct cpu *cpu)
 {
 	int rc;

 	rc = sysfs_create_group(&cpu->dev.kobj, &topology_cpu_attr_group);
 	if (rc || !MACHINE_HAS_TOPOLOGY)
 		return rc;
 	rc = sysfs_create_group(&cpu->dev.kobj, &topology_extra_cpu_attr_group);
 	if (rc)
 		sysfs_remove_group(&cpu->dev.kobj, &topology_cpu_attr_group);
 	return rc;
 }

 static const struct cpumask *cpu_thread_mask(int cpu)
 {
 	return &cpu_topology[cpu].thread_mask;
 }


 const struct cpumask *cpu_coregroup_mask(int cpu)
 {
 	return &cpu_topology[cpu].core_mask;
 }

 static const struct cpumask *cpu_book_mask(int cpu)
 {
 	return &cpu_topology[cpu].book_mask;
 }

 static const struct cpumask *cpu_drawer_mask(int cpu)
 {
 	return &cpu_topology[cpu].drawer_mask;
 }

 static struct sched_domain_topology_level s390_topology[] = {
 	{ cpu_thread_mask, cpu_smt_flags, SD_INIT_NAME(SMT) },
 	{ cpu_coregroup_mask, cpu_core_flags, SD_INIT_NAME(MC) },
 	{ cpu_book_mask, SD_INIT_NAME(BOOK) },
 	{ cpu_drawer_mask, SD_INIT_NAME(DRAWER) },
 	{ cpu_cpu_mask, SD_INIT_NAME(DIE) },
 	{ NULL, },
 };

 static void __init alloc_masks(struct sysinfo_15_1_x *info,
 			       struct mask_info *mask, int offset)
 {
 	int i, nr_masks;

 	nr_masks = info->mag[TOPOLOGY_NR_MAG - offset];
 	for (i = 0; i < info->mnest - offset; i++)
 		nr_masks *= info->mag[TOPOLOGY_NR_MAG - offset - 1 - i];
 	nr_masks = max(nr_masks, 1);
 	for (i = 0; i < nr_masks; i++) {
 		mask->next = memblock_virt_alloc(sizeof(*mask->next), 8);
 		mask = mask->next;
 	}
 }

 void __init topology_init_early(void)
 {
 	struct sysinfo_15_1_x *info;

 	set_sched_topology(s390_topology);
 	if (topology_mode == TOPOLOGY_MODE_UNINITIALIZED) {
 		if (MACHINE_HAS_TOPOLOGY)
 			topology_mode = TOPOLOGY_MODE_HW;
 		else
 			topology_mode = TOPOLOGY_MODE_SINGLE;
 	}
 	if (!MACHINE_HAS_TOPOLOGY)
 		goto out;
 	tl_info = memblock_virt_alloc(PAGE_SIZE, PAGE_SIZE);
 	info = tl_info;
 	store_topology(info);
 	pr_info("The CPU configuration topology of the machine is: %d %d %d %d %d %d / %d\n",
 		info->mag[0], info->mag[1], info->mag[2], info->mag[3],
 		info->mag[4], info->mag[5], info->mnest);
 	alloc_masks(info, &socket_info, 1);
 	alloc_masks(info, &book_info, 2);
 	alloc_masks(info, &drawer_info, 3);
 out:
 	__arch_update_cpu_topology();
 	__arch_update_dedicated_flag(NULL);
 }

 static inline int topology_get_mode(int enabled)
 {
 	if (!enabled)
 		return TOPOLOGY_MODE_SINGLE;
 	return MACHINE_HAS_TOPOLOGY ? TOPOLOGY_MODE_HW : TOPOLOGY_MODE_PACKAGE;
 }

 static inline int topology_is_enabled(void)
 {
 	return topology_mode != TOPOLOGY_MODE_SINGLE;
 }

 static int __init topology_setup(char *str)
 {
 	bool enabled;
 	int rc;

 	rc = kstrtobool(str, &enabled);
 	if (rc)
 		return rc;
 	topology_mode = topology_get_mode(enabled);
 	return 0;
 }
 early_param("topology", topology_setup);

 static int topology_ctl_handler(struct ctl_table *ctl, int write,
 				void __user *buffer, size_t *lenp, loff_t *ppos)
 {
 	int enabled = topology_is_enabled();
 	int new_mode;
 	int zero = 0;
 	int one = 1;
 	int rc;
 	struct ctl_table ctl_entry = {
 		.procname	= ctl->procname,
 		.data		= &enabled,
 		.maxlen		= sizeof(int),
 		.extra1		= &zero,
 		.extra2		= &one,
 	};

 	rc = proc_douintvec_minmax(&ctl_entry, write, buffer, lenp, ppos);
 	if (rc < 0 || !write)
 		return rc;

 	mutex_lock(&smp_cpu_state_mutex);
 	new_mode = topology_get_mode(enabled);
 	if (topology_mode != new_mode) {
 		topology_mode = new_mode;
 		topology_schedule_update();
 	}
 	mutex_unlock(&smp_cpu_state_mutex);
 	topology_flush_work();

 	return rc;
 }

 static struct ctl_table topology_ctl_table[] = {
 	{
 		.procname	= "topology",
 		.mode		= 0644,
 		.proc_handler	= topology_ctl_handler,
 	},
 	{ },
 };

 static struct ctl_table topology_dir_table[] = {
 	{
 		.procname	= "s390",
 		.maxlen		= 0,
 		.mode		= 0555,
 		.child		= topology_ctl_table,
 	},
 	{ },
 };

 static int __init topology_init(void)
 {
 	timer_setup(&topology_timer, topology_timer_fn, TIMER_DEFERRABLE);
 	if (MACHINE_HAS_TOPOLOGY)
 		set_topology_timer();
 	else
 		topology_update_polarization_simple();
 	register_sysctl_table(topology_dir_table);
 	return device_create_file(cpu_subsys.dev_root, &dev_attr_dispatching);
 }
 device_initcall(topology_init);
	// SPDX-License-Identifier: GPL-2.0
	/*
	* Copyright IBM Corp. 2007, 2011
	* Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
	*/

	#define KMSG_COMPONENT "cpu"
	#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt

	#include <linux/workqueue.h>
	#include <linux/bootmem.h>
	#include <linux/uaccess.h>
	#include <linux/sysctl.h>
	#include <linux/cpuset.h>
	#include <linux/device.h>
	#include <linux/export.h>
	#include <linux/kernel.h>
	#include <linux/sched.h>
	#include <linux/sched/topology.h>
	#include <linux/delay.h>
	#include <linux/init.h>
	#include <linux/slab.h>
	#include <linux/cpu.h>
	#include <linux/smp.h>
	#include <linux/mm.h>
	#include <linux/nodemask.h>
	#include <linux/node.h>
	#include <asm/sysinfo.h>
	#include <asm/numa.h>

	#define PTF_HORIZONTAL (0UL)
	#define PTF_VERTICAL (1UL)
	#define PTF_CHECK (2UL)

	enum {
	TOPOLOGY_MODE_HW,
	TOPOLOGY_MODE_SINGLE,
	TOPOLOGY_MODE_PACKAGE,
	TOPOLOGY_MODE_UNINITIALIZED
	};

	struct mask_info {
	struct mask_info *next;
	unsigned char id;
	cpumask_t mask;
	};

	static int topology_mode = TOPOLOGY_MODE_UNINITIALIZED;
	static void set_topology_timer(void);
	static void topology_work_fn(struct work_struct *work);
	static struct sysinfo_15_1_x *tl_info;

	static DECLARE_WORK(topology_work, topology_work_fn);

	/*
	* Socket/Book linked lists and cpu_topology updates are
	* protected by "sched_domains_mutex".
	*/
	static struct mask_info socket_info;
	static struct mask_info book_info;
	static struct mask_info drawer_info;

	struct cpu_topology_s390 cpu_topology[NR_CPUS];
	EXPORT_SYMBOL_GPL(cpu_topology);

	cpumask_t cpus_with_topology;

	static cpumask_t cpu_group_map(struct mask_info *info, unsigned int cpu)
	{
	cpumask_t mask;

	cpumask_copy(&mask, cpumask_of(cpu));
	switch (topology_mode) {
	case TOPOLOGY_MODE_HW:
	while (info) {
	if (cpumask_test_cpu(cpu, &info->mask)) {
	mask = info->mask;
	break;
	}
	info = info->next;
	}
	if (cpumask_empty(&mask))
	cpumask_copy(&mask, cpumask_of(cpu));
	break;
	case TOPOLOGY_MODE_PACKAGE:
	cpumask_copy(&mask, cpu_present_mask);
	break;
	default:
	/* fallthrough */
	case TOPOLOGY_MODE_SINGLE:
	cpumask_copy(&mask, cpumask_of(cpu));
	break;
	}
	return mask;
	}

	static cpumask_t cpu_thread_map(unsigned int cpu)
	{
	cpumask_t mask;
	int i;

	cpumask_copy(&mask, cpumask_of(cpu));
	if (topology_mode != TOPOLOGY_MODE_HW)
	return mask;
	cpu -= cpu % (smp_cpu_mtid + 1);
	for (i = 0; i <= smp_cpu_mtid; i++)
	if (cpu_present(cpu + i))
	cpumask_set_cpu(cpu + i, &mask);
	return mask;
	}

	#define TOPOLOGY_CORE_BITS 64

	static void add_cpus_to_mask(struct topology_core *tl_core,
	struct mask_info *drawer,
	struct mask_info *book,
	struct mask_info *socket)
	{
	struct cpu_topology_s390 *topo;
	unsigned int core;

	for_each_set_bit(core, &tl_core->mask, TOPOLOGY_CORE_BITS) {
	unsigned int rcore;
	int lcpu, i;

	rcore = TOPOLOGY_CORE_BITS - 1 - core + tl_core->origin;
	lcpu = smp_find_processor_id(rcore << smp_cpu_mt_shift);
	if (lcpu < 0)
	continue;
	for (i = 0; i <= smp_cpu_mtid; i++) {
	topo = &cpu_topology[lcpu + i];
	topo->drawer_id = drawer->id;
	topo->book_id = book->id;
	topo->socket_id = socket->id;
	topo->core_id = rcore;
	topo->thread_id = lcpu + i;
	topo->dedicated = tl_core->d;
	cpumask_set_cpu(lcpu + i, &drawer->mask);
	cpumask_set_cpu(lcpu + i, &book->mask);
	cpumask_set_cpu(lcpu + i, &socket->mask);
	cpumask_set_cpu(lcpu + i, &cpus_with_topology);
	smp_cpu_set_polarization(lcpu + i, tl_core->pp);
	}
	}
	}

	static void clear_masks(void)
	{
	struct mask_info *info;

	info = &socket_info;
	while (info) {
	cpumask_clear(&info->mask);
	info = info->next;
	}
	info = &book_info;
	while (info) {
	cpumask_clear(&info->mask);
	info = info->next;
	}
	info = &drawer_info;
	while (info) {
	cpumask_clear(&info->mask);
	info = info->next;
	}
	}

	static union topology_entry next_tle(union topology_entry tle)
	{
	if (!tle->nl)
	return (union topology_entry )((struct topology_core )tle + 1);
	return (union topology_entry )((struct topology_container )tle + 1);
	}

	static void tl_to_masks(struct sysinfo_15_1_x *info)
	{
	struct mask_info *socket = &socket_info;
	struct mask_info *book = &book_info;
	struct mask_info *drawer = &drawer_info;
	union topology_entry tle, end;

	clear_masks();
	tle = info->tle;
	end = (union topology_entry *)((unsigned long)info + info->length);
	while (tle < end) {
	switch (tle->nl) {
	case 3:
	drawer = drawer->next;
	drawer->id = tle->container.id;
	break;
	case 2:
	book = book->next;
	book->id = tle->container.id;
	break;
	case 1:
	socket = socket->next;
	socket->id = tle->container.id;
	break;
	case 0:
	add_cpus_to_mask(&tle->cpu, drawer, book, socket);
	break;
	default:
	clear_masks();
	return;
	}
	tle = next_tle(tle);
	}
	}

	static void topology_update_polarization_simple(void)
	{
	int cpu;

	for_each_possible_cpu(cpu)
	smp_cpu_set_polarization(cpu, POLARIZATION_HRZ);
	}

	static int ptf(unsigned long fc)
	{
	int rc;

	asm volatile(
	" .insn rre,0xb9a20000,%1,%1\n"
	" ipm %0\n"
	" srl %0,28\n"
	: "=d" (rc)
	: "d" (fc) : "cc");
	return rc;
	}

	int topology_set_cpu_management(int fc)
	{
	int cpu, rc;

	if (!MACHINE_HAS_TOPOLOGY)
	return -EOPNOTSUPP;
	if (fc)
	rc = ptf(PTF_VERTICAL);
	else
	rc = ptf(PTF_HORIZONTAL);
	if (rc)
	return -EBUSY;
	for_each_possible_cpu(cpu)
	smp_cpu_set_polarization(cpu, POLARIZATION_UNKNOWN);
	return rc;
	}

	static void update_cpu_masks(void)
	{
	struct cpu_topology_s390 *topo;
	int cpu, id;

	for_each_possible_cpu(cpu) {
	topo = &cpu_topology[cpu];
	topo->thread_mask = cpu_thread_map(cpu);
	topo->core_mask = cpu_group_map(&socket_info, cpu);
	topo->book_mask = cpu_group_map(&book_info, cpu);
	topo->drawer_mask = cpu_group_map(&drawer_info, cpu);
	if (topology_mode != TOPOLOGY_MODE_HW) {
	id = topology_mode == TOPOLOGY_MODE_PACKAGE ? 0 : cpu;
	topo->thread_id = cpu;
	topo->core_id = cpu;
	topo->socket_id = id;
	topo->book_id = id;
	topo->drawer_id = id;
	if (cpu_present(cpu))
	cpumask_set_cpu(cpu, &cpus_with_topology);
	}
	}
	numa_update_cpu_topology();
	}

	void store_topology(struct sysinfo_15_1_x *info)
	{
	stsi(info, 15, 1, topology_mnest_limit());
	}

	static void __arch_update_dedicated_flag(void *arg)
	{
	if (topology_cpu_dedicated(smp_processor_id()))
	set_cpu_flag(CIF_DEDICATED_CPU);
	else
	clear_cpu_flag(CIF_DEDICATED_CPU);
	}

	static int __arch_update_cpu_topology(void)
	{
	struct sysinfo_15_1_x *info = tl_info;
	int rc = 0;

	mutex_lock(&smp_cpu_state_mutex);
	cpumask_clear(&cpus_with_topology);
	if (MACHINE_HAS_TOPOLOGY) {
	rc = 1;
	store_topology(info);
	tl_to_masks(info);
	}
	update_cpu_masks();
	if (!MACHINE_HAS_TOPOLOGY)
	topology_update_polarization_simple();
	mutex_unlock(&smp_cpu_state_mutex);
	return rc;
	}

	int arch_update_cpu_topology(void)
	{
	struct device *dev;
	int cpu, rc;

	rc = __arch_update_cpu_topology();
	on_each_cpu(__arch_update_dedicated_flag, NULL, 0);
	for_each_online_cpu(cpu) {
	dev = get_cpu_device(cpu);
	kobject_uevent(&dev->kobj, KOBJ_CHANGE);
	}
	return rc;
	}

	static void topology_work_fn(struct work_struct *work)
	{
	rebuild_sched_domains();
	}

	void topology_schedule_update(void)
	{
	schedule_work(&topology_work);
	}

	static void topology_flush_work(void)
	{
	flush_work(&topology_work);
	}

	static void topology_timer_fn(struct timer_list *unused)
	{
	if (ptf(PTF_CHECK))
	topology_schedule_update();
	set_topology_timer();
	}

	static struct timer_list topology_timer;

	static atomic_t topology_poll = ATOMIC_INIT(0);

	static void set_topology_timer(void)
	{
	if (atomic_add_unless(&topology_poll, -1, 0))
	mod_timer(&topology_timer, jiffies + HZ / 10);
	else
	mod_timer(&topology_timer, jiffies + HZ * 60);
	}

	void topology_expect_change(void)
	{
	if (!MACHINE_HAS_TOPOLOGY)
	return;
	/* This is racy, but it doesn't matter since it is just a heuristic.
	* Worst case is that we poll in a higher frequency for a bit longer.
	*/
	if (atomic_read(&topology_poll) > 60)
	return;
	atomic_add(60, &topology_poll);
	set_topology_timer();
	}

	static int cpu_management;

	static ssize_t dispatching_show(struct device *dev,
	struct device_attribute *attr,
	char *buf)
	{
	ssize_t count;

	mutex_lock(&smp_cpu_state_mutex);
	count = sprintf(buf, "%d\n", cpu_management);
	mutex_unlock(&smp_cpu_state_mutex);
	return count;
	}

	static ssize_t dispatching_store(struct device *dev,
	struct device_attribute *attr,
	const char *buf,
	size_t count)
	{
	int val, rc;
	char delim;

	if (sscanf(buf, "%d %c", &val, &delim) != 1)
	return -EINVAL;
	if (val != 0 && val != 1)
	return -EINVAL;
	rc = 0;
	get_online_cpus();
	mutex_lock(&smp_cpu_state_mutex);
	if (cpu_management == val)
	goto out;
	rc = topology_set_cpu_management(val);
	if (rc)
	goto out;
	cpu_management = val;
	topology_expect_change();
	out:
	mutex_unlock(&smp_cpu_state_mutex);
	put_online_cpus();
	return rc ? rc : count;
	}
	static DEVICE_ATTR_RW(dispatching);

	static ssize_t cpu_polarization_show(struct device *dev,
	struct device_attribute attr, char buf)
	{
	int cpu = dev->id;
	ssize_t count;

	mutex_lock(&smp_cpu_state_mutex);
	switch (smp_cpu_get_polarization(cpu)) {
	case POLARIZATION_HRZ:
	count = sprintf(buf, "horizontal\n");
	break;
	case POLARIZATION_VL:
	count = sprintf(buf, "vertical:low\n");
	break;
	case POLARIZATION_VM:
	count = sprintf(buf, "vertical:medium\n");
	break;
	case POLARIZATION_VH:
	count = sprintf(buf, "vertical:high\n");
	break;
	default:
	count = sprintf(buf, "unknown\n");
	break;
	}
	mutex_unlock(&smp_cpu_state_mutex);
	return count;
	}
	static DEVICE_ATTR(polarization, 0444, cpu_polarization_show, NULL);

	static struct attribute *topology_cpu_attrs[] = {
	&dev_attr_polarization.attr,
	NULL,
	};

	static struct attribute_group topology_cpu_attr_group = {
	.attrs = topology_cpu_attrs,
	};

	static ssize_t cpu_dedicated_show(struct device *dev,
	struct device_attribute attr, char buf)
	{
	int cpu = dev->id;
	ssize_t count;

	mutex_lock(&smp_cpu_state_mutex);
	count = sprintf(buf, "%d\n", topology_cpu_dedicated(cpu));
	mutex_unlock(&smp_cpu_state_mutex);
	return count;
	}
	static DEVICE_ATTR(dedicated, 0444, cpu_dedicated_show, NULL);

	static struct attribute *topology_extra_cpu_attrs[] = {
	&dev_attr_dedicated.attr,
	NULL,
	};

	static struct attribute_group topology_extra_cpu_attr_group = {
	.attrs = topology_extra_cpu_attrs,
	};

	int topology_cpu_init(struct cpu *cpu)
	{
	int rc;

	rc = sysfs_create_group(&cpu->dev.kobj, &topology_cpu_attr_group);
	if (rc \|\| !MACHINE_HAS_TOPOLOGY)
	return rc;
	rc = sysfs_create_group(&cpu->dev.kobj, &topology_extra_cpu_attr_group);
	if (rc)
	sysfs_remove_group(&cpu->dev.kobj, &topology_cpu_attr_group);
	return rc;
	}

	static const struct cpumask *cpu_thread_mask(int cpu)
	{
	return &cpu_topology[cpu].thread_mask;
	}


	const struct cpumask *cpu_coregroup_mask(int cpu)
	{
	return &cpu_topology[cpu].core_mask;
	}

	static const struct cpumask *cpu_book_mask(int cpu)
	{
	return &cpu_topology[cpu].book_mask;
	}

	static const struct cpumask *cpu_drawer_mask(int cpu)
	{
	return &cpu_topology[cpu].drawer_mask;
	}

	static struct sched_domain_topology_level s390_topology[] = {
	{ cpu_thread_mask, cpu_smt_flags, SD_INIT_NAME(SMT) },
	{ cpu_coregroup_mask, cpu_core_flags, SD_INIT_NAME(MC) },
	{ cpu_book_mask, SD_INIT_NAME(BOOK) },
	{ cpu_drawer_mask, SD_INIT_NAME(DRAWER) },
	{ cpu_cpu_mask, SD_INIT_NAME(DIE) },
	{ NULL, },
	};

	static void __init alloc_masks(struct sysinfo_15_1_x *info,
	struct mask_info *mask, int offset)
	{
	int i, nr_masks;

	nr_masks = info->mag[TOPOLOGY_NR_MAG - offset];
	for (i = 0; i < info->mnest - offset; i++)
	nr_masks *= info->mag[TOPOLOGY_NR_MAG - offset - 1 - i];
	nr_masks = max(nr_masks, 1);
	for (i = 0; i < nr_masks; i++) {
	mask->next = memblock_virt_alloc(sizeof(*mask->next), 8);
	mask = mask->next;
	}
	}

	void __init topology_init_early(void)
	{
	struct sysinfo_15_1_x *info;

	set_sched_topology(s390_topology);
	if (topology_mode == TOPOLOGY_MODE_UNINITIALIZED) {
	if (MACHINE_HAS_TOPOLOGY)
	topology_mode = TOPOLOGY_MODE_HW;
	else
	topology_mode = TOPOLOGY_MODE_SINGLE;
	}
	if (!MACHINE_HAS_TOPOLOGY)
	goto out;
	tl_info = memblock_virt_alloc(PAGE_SIZE, PAGE_SIZE);
	info = tl_info;
	store_topology(info);
	pr_info("The CPU configuration topology of the machine is: %d %d %d %d %d %d / %d\n",
	info->mag[0], info->mag[1], info->mag[2], info->mag[3],
	info->mag[4], info->mag[5], info->mnest);
	alloc_masks(info, &socket_info, 1);
	alloc_masks(info, &book_info, 2);
	alloc_masks(info, &drawer_info, 3);
	out:
	__arch_update_cpu_topology();
	__arch_update_dedicated_flag(NULL);
	}

	static inline int topology_get_mode(int enabled)
	{
	if (!enabled)
	return TOPOLOGY_MODE_SINGLE;
	return MACHINE_HAS_TOPOLOGY ? TOPOLOGY_MODE_HW : TOPOLOGY_MODE_PACKAGE;
	}

	static inline int topology_is_enabled(void)
	{
	return topology_mode != TOPOLOGY_MODE_SINGLE;
	}

	static int __init topology_setup(char *str)
	{
	bool enabled;
	int rc;

	rc = kstrtobool(str, &enabled);
	if (rc)
	return rc;
	topology_mode = topology_get_mode(enabled);
	return 0;
	}
	early_param("topology", topology_setup);

	static int topology_ctl_handler(struct ctl_table *ctl, int write,
	void __user buffer, size_t lenp, loff_t *ppos)
	{
	int enabled = topology_is_enabled();
	int new_mode;
	int zero = 0;
	int one = 1;
	int rc;
	struct ctl_table ctl_entry = {
	.procname = ctl->procname,
	.data = &enabled,
	.maxlen = sizeof(int),
	.extra1 = &zero,
	.extra2 = &one,
	};

	rc = proc_douintvec_minmax(&ctl_entry, write, buffer, lenp, ppos);
	if (rc < 0 \|\| !write)
	return rc;

	mutex_lock(&smp_cpu_state_mutex);
	new_mode = topology_get_mode(enabled);
	if (topology_mode != new_mode) {
	topology_mode = new_mode;
	topology_schedule_update();
	}
	mutex_unlock(&smp_cpu_state_mutex);
	topology_flush_work();

	return rc;
	}

	static struct ctl_table topology_ctl_table[] = {
	{
	.procname = "topology",
	.mode = 0644,
	.proc_handler = topology_ctl_handler,
	},
	{ },
	};

	static struct ctl_table topology_dir_table[] = {
	{
	.procname = "s390",
	.maxlen = 0,
	.mode = 0555,
	.child = topology_ctl_table,
	},
	{ },
	};

	static int __init topology_init(void)
	{
	timer_setup(&topology_timer, topology_timer_fn, TIMER_DEFERRABLE);
	if (MACHINE_HAS_TOPOLOGY)
	set_topology_timer();
	else
	topology_update_polarization_simple();
	register_sysctl_table(topology_dir_table);
	return device_create_file(cpu_subsys.dev_root, &dev_attr_dispatching);
	}
	device_initcall(topology_init);