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

 /*
  *    Copyright IBM Corp. 2007
  *    Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
  */

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

 #include <linux/kernel.h>
 #include <linux/mm.h>
 #include <linux/init.h>
 #include <linux/device.h>
 #include <linux/bootmem.h>
 #include <linux/sched.h>
 #include <linux/workqueue.h>
 #include <linux/cpu.h>
 #include <linux/smp.h>
 #include <linux/cpuset.h>
 #include <asm/delay.h>
 #include <asm/s390_ext.h>
 #include <asm/sysinfo.h>

 #define CPU_BITS 64
 #define NR_MAG 6

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

 struct tl_cpu {
 	unsigned char reserved0[4];
 	unsigned char :6;
 	unsigned char pp:2;
 	unsigned char reserved1;
 	unsigned short origin;
 	unsigned long mask[CPU_BITS / BITS_PER_LONG];
 };

 struct tl_container {
 	unsigned char reserved[8];
 };

 union tl_entry {
 	unsigned char nl;
 	struct tl_cpu cpu;
 	struct tl_container container;
 };

 struct tl_info {
 	unsigned char reserved0[2];
 	unsigned short length;
 	unsigned char mag[NR_MAG];
 	unsigned char reserved1;
 	unsigned char mnest;
 	unsigned char reserved2[4];
 	union tl_entry tle[0];
 };

 struct core_info {
 	struct core_info *next;
 	cpumask_t mask;
 };

 static int topology_enabled;
 static void topology_work_fn(struct work_struct *work);
 static struct tl_info *tl_info;
 static struct core_info core_info;
 static int machine_has_topology;
 static struct timer_list topology_timer;
 static void set_topology_timer(void);
 static DECLARE_WORK(topology_work, topology_work_fn);
 /* topology_lock protects the core linked list */
 static DEFINE_SPINLOCK(topology_lock);

 cpumask_t cpu_core_map[NR_CPUS];

 static cpumask_t cpu_coregroup_map(unsigned int cpu)
 {
 	struct core_info *core = &core_info;
 	unsigned long flags;
 	cpumask_t mask;

 	cpus_clear(mask);
 	if (!topology_enabled || !machine_has_topology)
 		return cpu_possible_map;
 	spin_lock_irqsave(&topology_lock, flags);
 	while (core) {
 		if (cpu_isset(cpu, core->mask)) {
 			mask = core->mask;
 			break;
 		}
 		core = core->next;
 	}
 	spin_unlock_irqrestore(&topology_lock, flags);
 	if (cpus_empty(mask))
 		mask = cpumask_of_cpu(cpu);
 	return mask;
 }

 const struct cpumask *cpu_coregroup_mask(unsigned int cpu)
 {
 	return &cpu_core_map[cpu];
 }

 static void add_cpus_to_core(struct tl_cpu *tl_cpu, struct core_info *core)
 {
 	unsigned int cpu;

 	for (cpu = find_first_bit(&tl_cpu->mask[0], CPU_BITS);
 	     cpu < CPU_BITS;
 	     cpu = find_next_bit(&tl_cpu->mask[0], CPU_BITS, cpu + 1))
 	{
 		unsigned int rcpu, lcpu;

 		rcpu = CPU_BITS - 1 - cpu + tl_cpu->origin;
 		for_each_present_cpu(lcpu) {
 			if (__cpu_logical_map[lcpu] == rcpu) {
 				cpu_set(lcpu, core->mask);
 				smp_cpu_polarization[lcpu] = tl_cpu->pp;
 			}
 		}
 	}
 }

 static void clear_cores(void)
 {
 	struct core_info *core = &core_info;

 	while (core) {
 		cpus_clear(core->mask);
 		core = core->next;
 	}
 }

 static union tl_entry *next_tle(union tl_entry *tle)
 {
 	if (tle->nl)
 		return (union tl_entry *)((struct tl_container *)tle + 1);
 	else
 		return (union tl_entry *)((struct tl_cpu *)tle + 1);
 }

 static void tl_to_cores(struct tl_info *info)
 {
 	union tl_entry *tle, *end;
 	struct core_info *core = &core_info;

 	spin_lock_irq(&topology_lock);
 	clear_cores();
 	tle = info->tle;
 	end = (union tl_entry *)((unsigned long)info + info->length);
 	while (tle < end) {
 		switch (tle->nl) {
 		case 5:
 		case 4:
 		case 3:
 		case 2:
 			break;
 		case 1:
 			core = core->next;
 			break;
 		case 0:
 			add_cpus_to_core(&tle->cpu, core);
 			break;
 		default:
 			clear_cores();
 			machine_has_topology = 0;
 			return;
 		}
 		tle = next_tle(tle);
 	}
 	spin_unlock_irq(&topology_lock);
 }

 static void topology_update_polarization_simple(void)
 {
 	int cpu;

 	mutex_lock(&smp_cpu_state_mutex);
 	for_each_possible_cpu(cpu)
 		smp_cpu_polarization[cpu] = POLARIZATION_HRZ;
 	mutex_unlock(&smp_cpu_state_mutex);
 }

 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;
 	int 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_polarization[cpu] = POLARIZATION_UNKNWN;
 	return rc;
 }

 static void update_cpu_core_map(void)
 {
 	int cpu;

 	for_each_possible_cpu(cpu)
 		cpu_core_map[cpu] = cpu_coregroup_map(cpu);
 }

 int arch_update_cpu_topology(void)
 {
 	struct tl_info *info = tl_info;
 	struct sys_device *sysdev;
 	int cpu;

 	if (!machine_has_topology) {
 		update_cpu_core_map();
 		topology_update_polarization_simple();
 		return 0;
 	}
 	stsi(info, 15, 1, 2);
 	tl_to_cores(info);
 	update_cpu_core_map();
 	for_each_online_cpu(cpu) {
 		sysdev = get_cpu_sysdev(cpu);
 		kobject_uevent(&sysdev->kobj, KOBJ_CHANGE);
 	}
 	return 1;
 }

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

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

 static void topology_timer_fn(unsigned long ignored)
 {
 	if (ptf(PTF_CHECK))
 		topology_schedule_update();
 	set_topology_timer();
 }

 static void set_topology_timer(void)
 {
 	topology_timer.function = topology_timer_fn;
 	topology_timer.data = 0;
 	topology_timer.expires = jiffies + 60 * HZ;
 	add_timer(&topology_timer);
 }

 static int __init early_parse_topology(char *p)
 {
 	if (strncmp(p, "on", 2))
 		return 0;
 	topology_enabled = 1;
 	return 0;
 }
 early_param("topology", early_parse_topology);

 static int __init init_topology_update(void)
 {
 	int rc;

 	rc = 0;
 	if (!machine_has_topology) {
 		topology_update_polarization_simple();
 		goto out;
 	}
 	init_timer_deferrable(&topology_timer);
 	set_topology_timer();
 out:
 	update_cpu_core_map();
 	return rc;
 }
 __initcall(init_topology_update);

 void __init s390_init_cpu_topology(void)
 {
 	unsigned long long facility_bits;
 	struct tl_info *info;
 	struct core_info *core;
 	int nr_cores;
 	int i;

 	if (stfle(&facility_bits, 1) <= 0)
 		return;
 	if (!(facility_bits & (1ULL << 52)) || !(facility_bits & (1ULL << 61)))
 		return;
 	machine_has_topology = 1;

 	tl_info = alloc_bootmem_pages(PAGE_SIZE);
 	info = tl_info;
 	stsi(info, 15, 1, 2);

 	nr_cores = info->mag[NR_MAG - 2];
 	for (i = 0; i < info->mnest - 2; i++)
 		nr_cores *= info->mag[NR_MAG - 3 - i];

 	pr_info("The CPU configuration topology of the machine is:");
 	for (i = 0; i < NR_MAG; i++)
 		printk(" %d", info->mag[i]);
 	printk(" / %d\n", info->mnest);

 	core = &core_info;
 	for (i = 0; i < nr_cores; i++) {
 		core->next = alloc_bootmem(sizeof(struct core_info));
 		core = core->next;
 		if (!core)
 			goto error;
 	}
 	return;
 error:
 	machine_has_topology = 0;
 }
	/*
	* Copyright IBM Corp. 2007
	* Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
	*/

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

	#include <linux/kernel.h>
	#include <linux/mm.h>
	#include <linux/init.h>
	#include <linux/device.h>
	#include <linux/bootmem.h>
	#include <linux/sched.h>
	#include <linux/workqueue.h>
	#include <linux/cpu.h>
	#include <linux/smp.h>
	#include <linux/cpuset.h>
	#include <asm/delay.h>
	#include <asm/s390_ext.h>
	#include <asm/sysinfo.h>

	#define CPU_BITS 64
	#define NR_MAG 6

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

	struct tl_cpu {
	unsigned char reserved0[4];
	unsigned char :6;
	unsigned char pp:2;
	unsigned char reserved1;
	unsigned short origin;
	unsigned long mask[CPU_BITS / BITS_PER_LONG];
	};

	struct tl_container {
	unsigned char reserved[8];
	};

	union tl_entry {
	unsigned char nl;
	struct tl_cpu cpu;
	struct tl_container container;
	};

	struct tl_info {
	unsigned char reserved0[2];
	unsigned short length;
	unsigned char mag[NR_MAG];
	unsigned char reserved1;
	unsigned char mnest;
	unsigned char reserved2[4];
	union tl_entry tle[0];
	};

	struct core_info {
	struct core_info *next;
	cpumask_t mask;
	};

	static int topology_enabled;
	static void topology_work_fn(struct work_struct *work);
	static struct tl_info *tl_info;
	static struct core_info core_info;
	static int machine_has_topology;
	static struct timer_list topology_timer;
	static void set_topology_timer(void);
	static DECLARE_WORK(topology_work, topology_work_fn);
	/* topology_lock protects the core linked list */
	static DEFINE_SPINLOCK(topology_lock);

	cpumask_t cpu_core_map[NR_CPUS];

	static cpumask_t cpu_coregroup_map(unsigned int cpu)
	{
	struct core_info *core = &core_info;
	unsigned long flags;
	cpumask_t mask;

	cpus_clear(mask);
	if (!topology_enabled \|\| !machine_has_topology)
	return cpu_possible_map;
	spin_lock_irqsave(&topology_lock, flags);
	while (core) {
	if (cpu_isset(cpu, core->mask)) {
	mask = core->mask;
	break;
	}
	core = core->next;
	}
	spin_unlock_irqrestore(&topology_lock, flags);
	if (cpus_empty(mask))
	mask = cpumask_of_cpu(cpu);
	return mask;
	}

	const struct cpumask *cpu_coregroup_mask(unsigned int cpu)
	{
	return &cpu_core_map[cpu];
	}

	static void add_cpus_to_core(struct tl_cpu tl_cpu, struct core_info core)
	{
	unsigned int cpu;

	for (cpu = find_first_bit(&tl_cpu->mask[0], CPU_BITS);
	cpu < CPU_BITS;
	cpu = find_next_bit(&tl_cpu->mask[0], CPU_BITS, cpu + 1))
	{
	unsigned int rcpu, lcpu;

	rcpu = CPU_BITS - 1 - cpu + tl_cpu->origin;
	for_each_present_cpu(lcpu) {
	if (__cpu_logical_map[lcpu] == rcpu) {
	cpu_set(lcpu, core->mask);
	smp_cpu_polarization[lcpu] = tl_cpu->pp;
	}
	}
	}
	}

	static void clear_cores(void)
	{
	struct core_info *core = &core_info;

	while (core) {
	cpus_clear(core->mask);
	core = core->next;
	}
	}

	static union tl_entry next_tle(union tl_entry tle)
	{
	if (tle->nl)
	return (union tl_entry )((struct tl_container )tle + 1);
	else
	return (union tl_entry )((struct tl_cpu )tle + 1);
	}

	static void tl_to_cores(struct tl_info *info)
	{
	union tl_entry tle, end;
	struct core_info *core = &core_info;

	spin_lock_irq(&topology_lock);
	clear_cores();
	tle = info->tle;
	end = (union tl_entry *)((unsigned long)info + info->length);
	while (tle < end) {
	switch (tle->nl) {
	case 5:
	case 4:
	case 3:
	case 2:
	break;
	case 1:
	core = core->next;
	break;
	case 0:
	add_cpus_to_core(&tle->cpu, core);
	break;
	default:
	clear_cores();
	machine_has_topology = 0;
	return;
	}
	tle = next_tle(tle);
	}
	spin_unlock_irq(&topology_lock);
	}

	static void topology_update_polarization_simple(void)
	{
	int cpu;

	mutex_lock(&smp_cpu_state_mutex);
	for_each_possible_cpu(cpu)
	smp_cpu_polarization[cpu] = POLARIZATION_HRZ;
	mutex_unlock(&smp_cpu_state_mutex);
	}

	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;
	int 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_polarization[cpu] = POLARIZATION_UNKNWN;
	return rc;
	}

	static void update_cpu_core_map(void)
	{
	int cpu;

	for_each_possible_cpu(cpu)
	cpu_core_map[cpu] = cpu_coregroup_map(cpu);
	}

	int arch_update_cpu_topology(void)
	{
	struct tl_info *info = tl_info;
	struct sys_device *sysdev;
	int cpu;

	if (!machine_has_topology) {
	update_cpu_core_map();
	topology_update_polarization_simple();
	return 0;
	}
	stsi(info, 15, 1, 2);
	tl_to_cores(info);
	update_cpu_core_map();
	for_each_online_cpu(cpu) {
	sysdev = get_cpu_sysdev(cpu);
	kobject_uevent(&sysdev->kobj, KOBJ_CHANGE);
	}
	return 1;
	}

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

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

	static void topology_timer_fn(unsigned long ignored)
	{
	if (ptf(PTF_CHECK))
	topology_schedule_update();
	set_topology_timer();
	}

	static void set_topology_timer(void)
	{
	topology_timer.function = topology_timer_fn;
	topology_timer.data = 0;
	topology_timer.expires = jiffies + 60 * HZ;
	add_timer(&topology_timer);
	}

	static int __init early_parse_topology(char *p)
	{
	if (strncmp(p, "on", 2))
	return 0;
	topology_enabled = 1;
	return 0;
	}
	early_param("topology", early_parse_topology);

	static int __init init_topology_update(void)
	{
	int rc;

	rc = 0;
	if (!machine_has_topology) {
	topology_update_polarization_simple();
	goto out;
	}
	init_timer_deferrable(&topology_timer);
	set_topology_timer();
	out:
	update_cpu_core_map();
	return rc;
	}
	__initcall(init_topology_update);

	void __init s390_init_cpu_topology(void)
	{
	unsigned long long facility_bits;
	struct tl_info *info;
	struct core_info *core;
	int nr_cores;
	int i;

	if (stfle(&facility_bits, 1) <= 0)
	return;
	if (!(facility_bits & (1ULL << 52)) \|\| !(facility_bits & (1ULL << 61)))
	return;
	machine_has_topology = 1;

	tl_info = alloc_bootmem_pages(PAGE_SIZE);
	info = tl_info;
	stsi(info, 15, 1, 2);

	nr_cores = info->mag[NR_MAG - 2];
	for (i = 0; i < info->mnest - 2; i++)
	nr_cores *= info->mag[NR_MAG - 3 - i];

	pr_info("The CPU configuration topology of the machine is:");
	for (i = 0; i < NR_MAG; i++)
	printk(" %d", info->mag[i]);
	printk(" / %d\n", info->mnest);

	core = &core_info;
	for (i = 0; i < nr_cores; i++) {
	core->next = alloc_bootmem(sizeof(struct core_info));
	core = core->next;
	if (!core)
	goto error;
	}
	return;
	error:
	machine_has_topology = 0;
	}