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

 /*
  * Extract CPU cache information and expose them via sysfs.
  *
  *    Copyright IBM Corp. 2012
  *    Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
  */

 #include <linux/notifier.h>
 #include <linux/seq_file.h>
 #include <linux/init.h>
 #include <linux/list.h>
 #include <linux/slab.h>
 #include <linux/cpu.h>
 #include <asm/facility.h>

 struct cache {
 	unsigned long size;
 	unsigned int line_size;
 	unsigned int associativity;
 	unsigned int nr_sets;
 	unsigned int level   : 3;
 	unsigned int type    : 2;
 	unsigned int private : 1;
 	struct list_head list;
 };

 struct cache_dir {
 	struct kobject *kobj;
 	struct cache_index_dir *index;
 };

 struct cache_index_dir {
 	struct kobject kobj;
 	int cpu;
 	struct cache *cache;
 	struct cache_index_dir *next;
 };

 enum {
 	CACHE_SCOPE_NOTEXISTS,
 	CACHE_SCOPE_PRIVATE,
 	CACHE_SCOPE_SHARED,
 	CACHE_SCOPE_RESERVED,
 };

 enum {
 	CACHE_TYPE_SEPARATE,
 	CACHE_TYPE_DATA,
 	CACHE_TYPE_INSTRUCTION,
 	CACHE_TYPE_UNIFIED,
 };

 enum {
 	EXTRACT_TOPOLOGY,
 	EXTRACT_LINE_SIZE,
 	EXTRACT_SIZE,
 	EXTRACT_ASSOCIATIVITY,
 };

 enum {
 	CACHE_TI_UNIFIED = 0,
 	CACHE_TI_DATA = 0,
 	CACHE_TI_INSTRUCTION,
 };

 struct cache_info {
 	unsigned char	    : 4;
 	unsigned char scope : 2;
 	unsigned char type  : 2;
 };

 #define CACHE_MAX_LEVEL 8

 union cache_topology {
 	struct cache_info ci[CACHE_MAX_LEVEL];
 	unsigned long long raw;
 };

 static const char * const cache_type_string[] = {
 	"Data",
 	"Instruction",
 	"Unified",
 };

 static struct cache_dir *cache_dir_cpu[NR_CPUS];
 static LIST_HEAD(cache_list);

 void show_cacheinfo(struct seq_file *m)
 {
 	struct cache *cache;
 	int index = 0;

 	list_for_each_entry(cache, &cache_list, list) {
 		seq_printf(m, "cache%-11d: ", index);
 		seq_printf(m, "level=%d ", cache->level);
 		seq_printf(m, "type=%s ", cache_type_string[cache->type]);
 		seq_printf(m, "scope=%s ", cache->private ? "Private" : "Shared");
 		seq_printf(m, "size=%luK ", cache->size >> 10);
 		seq_printf(m, "line_size=%u ", cache->line_size);
 		seq_printf(m, "associativity=%d", cache->associativity);
 		seq_puts(m, "\n");
 		index++;
 	}
 }

 static inline unsigned long ecag(int ai, int li, int ti)
 {
 	unsigned long cmd, val;

 	cmd = ai << 4 | li << 1 | ti;
 	asm volatile(".insn	rsy,0xeb000000004c,%0,0,0(%1)" /* ecag */
 		     : "=d" (val) : "a" (cmd));
 	return val;
 }

 static int __init cache_add(int level, int private, int type)
 {
 	struct cache *cache;
 	int ti;

 	cache = kzalloc(sizeof(*cache), GFP_KERNEL);
 	if (!cache)
 		return -ENOMEM;
 	if (type == CACHE_TYPE_INSTRUCTION)
 		ti = CACHE_TI_INSTRUCTION;
 	else
 		ti = CACHE_TI_UNIFIED;
 	cache->size = ecag(EXTRACT_SIZE, level, ti);
 	cache->line_size = ecag(EXTRACT_LINE_SIZE, level, ti);
 	cache->associativity = ecag(EXTRACT_ASSOCIATIVITY, level, ti);
 	cache->nr_sets = cache->size / cache->associativity;
 	cache->nr_sets /= cache->line_size;
 	cache->private = private;
 	cache->level = level + 1;
 	cache->type = type - 1;
 	list_add_tail(&cache->list, &cache_list);
 	return 0;
 }

 static void __init cache_build_info(void)
 {
 	struct cache *cache, *next;
 	union cache_topology ct;
 	int level, private, rc;

 	ct.raw = ecag(EXTRACT_TOPOLOGY, 0, 0);
 	for (level = 0; level < CACHE_MAX_LEVEL; level++) {
 		switch (ct.ci[level].scope) {
 		case CACHE_SCOPE_NOTEXISTS:
 		case CACHE_SCOPE_RESERVED:
 			return;
 		case CACHE_SCOPE_SHARED:
 			private = 0;
 			break;
 		case CACHE_SCOPE_PRIVATE:
 			private = 1;
 			break;
 		}
 		if (ct.ci[level].type == CACHE_TYPE_SEPARATE) {
 			rc  = cache_add(level, private, CACHE_TYPE_DATA);
 			rc |= cache_add(level, private, CACHE_TYPE_INSTRUCTION);
 		} else {
 			rc = cache_add(level, private, ct.ci[level].type);
 		}
 		if (rc)
 			goto error;
 	}
 	return;
 error:
 	list_for_each_entry_safe(cache, next, &cache_list, list) {
 		list_del(&cache->list);
 		kfree(cache);
 	}
 }

 static struct cache_dir *__cpuinit cache_create_cache_dir(int cpu)
 {
 	struct cache_dir *cache_dir;
 	struct kobject *kobj = NULL;
 	struct device *dev;

 	dev = get_cpu_device(cpu);
 	if (!dev)
 		goto out;
 	kobj = kobject_create_and_add("cache", &dev->kobj);
 	if (!kobj)
 		goto out;
 	cache_dir = kzalloc(sizeof(*cache_dir), GFP_KERNEL);
 	if (!cache_dir)
 		goto out;
 	cache_dir->kobj = kobj;
 	cache_dir_cpu[cpu] = cache_dir;
 	return cache_dir;
 out:
 	kobject_put(kobj);
 	return NULL;
 }

 static struct cache_index_dir *kobj_to_cache_index_dir(struct kobject *kobj)
 {
 	return container_of(kobj, struct cache_index_dir, kobj);
 }

 static void cache_index_release(struct kobject *kobj)
 {
 	struct cache_index_dir *index;

 	index = kobj_to_cache_index_dir(kobj);
 	kfree(index);
 }

 static ssize_t cache_index_show(struct kobject *kobj,
 				struct attribute *attr, char *buf)
 {
 	struct kobj_attribute *kobj_attr;

 	kobj_attr = container_of(attr, struct kobj_attribute, attr);
 	return kobj_attr->show(kobj, kobj_attr, buf);
 }

 #define DEFINE_CACHE_ATTR(_name, _format, _value)			\
 static ssize_t cache_##_name##_show(struct kobject *kobj,		\
 				    struct kobj_attribute *attr,	\
 				    char *buf)				\
 {									\
 	struct cache_index_dir *index;					\
 									\
 	index = kobj_to_cache_index_dir(kobj);				\
 	return sprintf(buf, _format, _value);				\
 }									\
 static struct kobj_attribute cache_##_name##_attr =			\
 	__ATTR(_name, 0444, cache_##_name##_show, NULL);

 DEFINE_CACHE_ATTR(size, "%luK\n", index->cache->size >> 10);
 DEFINE_CACHE_ATTR(coherency_line_size, "%u\n", index->cache->line_size);
 DEFINE_CACHE_ATTR(number_of_sets, "%u\n", index->cache->nr_sets);
 DEFINE_CACHE_ATTR(ways_of_associativity, "%u\n", index->cache->associativity);
 DEFINE_CACHE_ATTR(type, "%s\n", cache_type_string[index->cache->type]);
 DEFINE_CACHE_ATTR(level, "%d\n", index->cache->level);

 static ssize_t shared_cpu_map_func(struct kobject *kobj, int type, char *buf)
 {
 	struct cache_index_dir *index;
 	int len;

 	index = kobj_to_cache_index_dir(kobj);
 	len = type ?
 		cpulist_scnprintf(buf, PAGE_SIZE - 2, cpumask_of(index->cpu)) :
 		cpumask_scnprintf(buf, PAGE_SIZE - 2, cpumask_of(index->cpu));
 	len += sprintf(&buf[len], "\n");
 	return len;
 }

 static ssize_t shared_cpu_map_show(struct kobject *kobj,
 				   struct kobj_attribute *attr, char *buf)
 {
 	return shared_cpu_map_func(kobj, 0, buf);
 }
 static struct kobj_attribute cache_shared_cpu_map_attr =
 	__ATTR(shared_cpu_map, 0444, shared_cpu_map_show, NULL);

 static ssize_t shared_cpu_list_show(struct kobject *kobj,
 				    struct kobj_attribute *attr, char *buf)
 {
 	return shared_cpu_map_func(kobj, 1, buf);
 }
 static struct kobj_attribute cache_shared_cpu_list_attr =
 	__ATTR(shared_cpu_list, 0444, shared_cpu_list_show, NULL);

 static struct attribute *cache_index_default_attrs[] = {
 	&cache_type_attr.attr,
 	&cache_size_attr.attr,
 	&cache_number_of_sets_attr.attr,
 	&cache_ways_of_associativity_attr.attr,
 	&cache_level_attr.attr,
 	&cache_coherency_line_size_attr.attr,
 	&cache_shared_cpu_map_attr.attr,
 	&cache_shared_cpu_list_attr.attr,
 	NULL,
 };

 static const struct sysfs_ops cache_index_ops = {
 	.show = cache_index_show,
 };

 static struct kobj_type cache_index_type = {
 	.sysfs_ops = &cache_index_ops,
 	.release = cache_index_release,
 	.default_attrs = cache_index_default_attrs,
 };

 static int __cpuinit cache_create_index_dir(struct cache_dir *cache_dir,
 					    struct cache *cache, int index,
 					    int cpu)
 {
 	struct cache_index_dir *index_dir;
 	int rc;

 	index_dir = kzalloc(sizeof(*index_dir), GFP_KERNEL);
 	if (!index_dir)
 		return -ENOMEM;
 	index_dir->cache = cache;
 	index_dir->cpu = cpu;
 	rc = kobject_init_and_add(&index_dir->kobj, &cache_index_type,
 				  cache_dir->kobj, "index%d", index);
 	if (rc)
 		goto out;
 	index_dir->next = cache_dir->index;
 	cache_dir->index = index_dir;
 	return 0;
 out:
 	kfree(index_dir);
 	return rc;
 }

 static int __cpuinit cache_add_cpu(int cpu)
 {
 	struct cache_dir *cache_dir;
 	struct cache *cache;
 	int rc, index = 0;

 	if (list_empty(&cache_list))
 		return 0;
 	cache_dir = cache_create_cache_dir(cpu);
 	if (!cache_dir)
 		return -ENOMEM;
 	list_for_each_entry(cache, &cache_list, list) {
 		if (!cache->private)
 			break;
 		rc = cache_create_index_dir(cache_dir, cache, index, cpu);
 		if (rc)
 			return rc;
 		index++;
 	}
 	return 0;
 }

 static void __cpuinit cache_remove_cpu(int cpu)
 {
 	struct cache_index_dir *index, *next;
 	struct cache_dir *cache_dir;

 	cache_dir = cache_dir_cpu[cpu];
 	if (!cache_dir)
 		return;
 	index = cache_dir->index;
 	while (index) {
 		next = index->next;
 		kobject_put(&index->kobj);
 		index = next;
 	}
 	kobject_put(cache_dir->kobj);
 	kfree(cache_dir);
 	cache_dir_cpu[cpu] = NULL;
 }

 static int __cpuinit cache_hotplug(struct notifier_block *nfb,
 				   unsigned long action, void *hcpu)
 {
 	int cpu = (long)hcpu;
 	int rc = 0;

 	switch (action & ~CPU_TASKS_FROZEN) {
 	case CPU_ONLINE:
 		rc = cache_add_cpu(cpu);
 		if (rc)
 			cache_remove_cpu(cpu);
 		break;
 	case CPU_DEAD:
 		cache_remove_cpu(cpu);
 		break;
 	}
 	return rc ? NOTIFY_BAD : NOTIFY_OK;
 }

 static int __init cache_init(void)
 {
 	int cpu;

 	if (!test_facility(34))
 		return 0;
 	cache_build_info();
 	for_each_online_cpu(cpu)
 		cache_add_cpu(cpu);
 	hotcpu_notifier(cache_hotplug, 0);
 	return 0;
 }
 device_initcall(cache_init);
	/*
	* Extract CPU cache information and expose them via sysfs.
	*
	* Copyright IBM Corp. 2012
	* Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
	*/

	#include <linux/notifier.h>
	#include <linux/seq_file.h>
	#include <linux/init.h>
	#include <linux/list.h>
	#include <linux/slab.h>
	#include <linux/cpu.h>
	#include <asm/facility.h>

	struct cache {
	unsigned long size;
	unsigned int line_size;
	unsigned int associativity;
	unsigned int nr_sets;
	unsigned int level : 3;
	unsigned int type : 2;
	unsigned int private : 1;
	struct list_head list;
	};

	struct cache_dir {
	struct kobject *kobj;
	struct cache_index_dir *index;
	};

	struct cache_index_dir {
	struct kobject kobj;
	int cpu;
	struct cache *cache;
	struct cache_index_dir *next;
	};

	enum {
	CACHE_SCOPE_NOTEXISTS,
	CACHE_SCOPE_PRIVATE,
	CACHE_SCOPE_SHARED,
	CACHE_SCOPE_RESERVED,
	};

	enum {
	CACHE_TYPE_SEPARATE,
	CACHE_TYPE_DATA,
	CACHE_TYPE_INSTRUCTION,
	CACHE_TYPE_UNIFIED,
	};

	enum {
	EXTRACT_TOPOLOGY,
	EXTRACT_LINE_SIZE,
	EXTRACT_SIZE,
	EXTRACT_ASSOCIATIVITY,
	};

	enum {
	CACHE_TI_UNIFIED = 0,
	CACHE_TI_DATA = 0,
	CACHE_TI_INSTRUCTION,
	};

	struct cache_info {
	unsigned char : 4;
	unsigned char scope : 2;
	unsigned char type : 2;
	};

	#define CACHE_MAX_LEVEL 8

	union cache_topology {
	struct cache_info ci[CACHE_MAX_LEVEL];
	unsigned long long raw;
	};

	static const char * const cache_type_string[] = {
	"Data",
	"Instruction",
	"Unified",
	};

	static struct cache_dir *cache_dir_cpu[NR_CPUS];
	static LIST_HEAD(cache_list);

	void show_cacheinfo(struct seq_file *m)
	{
	struct cache *cache;
	int index = 0;

	list_for_each_entry(cache, &cache_list, list) {
	seq_printf(m, "cache%-11d: ", index);
	seq_printf(m, "level=%d ", cache->level);
	seq_printf(m, "type=%s ", cache_type_string[cache->type]);
	seq_printf(m, "scope=%s ", cache->private ? "Private" : "Shared");
	seq_printf(m, "size=%luK ", cache->size >> 10);
	seq_printf(m, "line_size=%u ", cache->line_size);
	seq_printf(m, "associativity=%d", cache->associativity);
	seq_puts(m, "\n");
	index++;
	}
	}

	static inline unsigned long ecag(int ai, int li, int ti)
	{
	unsigned long cmd, val;

	cmd = ai << 4 \| li << 1 \| ti;
	asm volatile(".insn rsy,0xeb000000004c,%0,0,0(%1)" /* ecag */
	: "=d" (val) : "a" (cmd));
	return val;
	}

	static int __init cache_add(int level, int private, int type)
	{
	struct cache *cache;
	int ti;

	cache = kzalloc(sizeof(*cache), GFP_KERNEL);
	if (!cache)
	return -ENOMEM;
	if (type == CACHE_TYPE_INSTRUCTION)
	ti = CACHE_TI_INSTRUCTION;
	else
	ti = CACHE_TI_UNIFIED;
	cache->size = ecag(EXTRACT_SIZE, level, ti);
	cache->line_size = ecag(EXTRACT_LINE_SIZE, level, ti);
	cache->associativity = ecag(EXTRACT_ASSOCIATIVITY, level, ti);
	cache->nr_sets = cache->size / cache->associativity;
	cache->nr_sets /= cache->line_size;
	cache->private = private;
	cache->level = level + 1;
	cache->type = type - 1;
	list_add_tail(&cache->list, &cache_list);
	return 0;
	}

	static void __init cache_build_info(void)
	{
	struct cache cache, next;
	union cache_topology ct;
	int level, private, rc;

	ct.raw = ecag(EXTRACT_TOPOLOGY, 0, 0);
	for (level = 0; level < CACHE_MAX_LEVEL; level++) {
	switch (ct.ci[level].scope) {
	case CACHE_SCOPE_NOTEXISTS:
	case CACHE_SCOPE_RESERVED:
	return;
	case CACHE_SCOPE_SHARED:
	private = 0;
	break;
	case CACHE_SCOPE_PRIVATE:
	private = 1;
	break;
	}
	if (ct.ci[level].type == CACHE_TYPE_SEPARATE) {
	rc = cache_add(level, private, CACHE_TYPE_DATA);
	rc \|= cache_add(level, private, CACHE_TYPE_INSTRUCTION);
	} else {
	rc = cache_add(level, private, ct.ci[level].type);
	}
	if (rc)
	goto error;
	}
	return;
	error:
	list_for_each_entry_safe(cache, next, &cache_list, list) {
	list_del(&cache->list);
	kfree(cache);
	}
	}

	static struct cache_dir *__cpuinit cache_create_cache_dir(int cpu)
	{
	struct cache_dir *cache_dir;
	struct kobject *kobj = NULL;
	struct device *dev;

	dev = get_cpu_device(cpu);
	if (!dev)
	goto out;
	kobj = kobject_create_and_add("cache", &dev->kobj);
	if (!kobj)
	goto out;
	cache_dir = kzalloc(sizeof(*cache_dir), GFP_KERNEL);
	if (!cache_dir)
	goto out;
	cache_dir->kobj = kobj;
	cache_dir_cpu[cpu] = cache_dir;
	return cache_dir;
	out:
	kobject_put(kobj);
	return NULL;
	}

	static struct cache_index_dir kobj_to_cache_index_dir(struct kobject kobj)
	{
	return container_of(kobj, struct cache_index_dir, kobj);
	}

	static void cache_index_release(struct kobject *kobj)
	{
	struct cache_index_dir *index;

	index = kobj_to_cache_index_dir(kobj);
	kfree(index);
	}

	static ssize_t cache_index_show(struct kobject *kobj,
	struct attribute attr, char buf)
	{
	struct kobj_attribute *kobj_attr;

	kobj_attr = container_of(attr, struct kobj_attribute, attr);
	return kobj_attr->show(kobj, kobj_attr, buf);
	}

	#define DEFINE_CACHE_ATTR(_name, _format, _value) \
	static ssize_t cache_##_name##_show(struct kobject *kobj, \
	struct kobj_attribute *attr, \
	char *buf) \
	{ \
	struct cache_index_dir *index; \
	\
	index = kobj_to_cache_index_dir(kobj); \
	return sprintf(buf, _format, _value); \
	} \
	static struct kobj_attribute cache_##_name##_attr = \
	__ATTR(_name, 0444, cache_##_name##_show, NULL);

	DEFINE_CACHE_ATTR(size, "%luK\n", index->cache->size >> 10);
	DEFINE_CACHE_ATTR(coherency_line_size, "%u\n", index->cache->line_size);
	DEFINE_CACHE_ATTR(number_of_sets, "%u\n", index->cache->nr_sets);
	DEFINE_CACHE_ATTR(ways_of_associativity, "%u\n", index->cache->associativity);
	DEFINE_CACHE_ATTR(type, "%s\n", cache_type_string[index->cache->type]);
	DEFINE_CACHE_ATTR(level, "%d\n", index->cache->level);

	static ssize_t shared_cpu_map_func(struct kobject kobj, int type, char buf)
	{
	struct cache_index_dir *index;
	int len;

	index = kobj_to_cache_index_dir(kobj);
	len = type ?
	cpulist_scnprintf(buf, PAGE_SIZE - 2, cpumask_of(index->cpu)) :
	cpumask_scnprintf(buf, PAGE_SIZE - 2, cpumask_of(index->cpu));
	len += sprintf(&buf[len], "\n");
	return len;
	}

	static ssize_t shared_cpu_map_show(struct kobject *kobj,
	struct kobj_attribute attr, char buf)
	{
	return shared_cpu_map_func(kobj, 0, buf);
	}
	static struct kobj_attribute cache_shared_cpu_map_attr =
	__ATTR(shared_cpu_map, 0444, shared_cpu_map_show, NULL);

	static ssize_t shared_cpu_list_show(struct kobject *kobj,
	struct kobj_attribute attr, char buf)
	{
	return shared_cpu_map_func(kobj, 1, buf);
	}
	static struct kobj_attribute cache_shared_cpu_list_attr =
	__ATTR(shared_cpu_list, 0444, shared_cpu_list_show, NULL);

	static struct attribute *cache_index_default_attrs[] = {
	&cache_type_attr.attr,
	&cache_size_attr.attr,
	&cache_number_of_sets_attr.attr,
	&cache_ways_of_associativity_attr.attr,
	&cache_level_attr.attr,
	&cache_coherency_line_size_attr.attr,
	&cache_shared_cpu_map_attr.attr,
	&cache_shared_cpu_list_attr.attr,
	NULL,
	};

	static const struct sysfs_ops cache_index_ops = {
	.show = cache_index_show,
	};

	static struct kobj_type cache_index_type = {
	.sysfs_ops = &cache_index_ops,
	.release = cache_index_release,
	.default_attrs = cache_index_default_attrs,
	};

	static int __cpuinit cache_create_index_dir(struct cache_dir *cache_dir,
	struct cache *cache, int index,
	int cpu)
	{
	struct cache_index_dir *index_dir;
	int rc;

	index_dir = kzalloc(sizeof(*index_dir), GFP_KERNEL);
	if (!index_dir)
	return -ENOMEM;
	index_dir->cache = cache;
	index_dir->cpu = cpu;
	rc = kobject_init_and_add(&index_dir->kobj, &cache_index_type,
	cache_dir->kobj, "index%d", index);
	if (rc)
	goto out;
	index_dir->next = cache_dir->index;
	cache_dir->index = index_dir;
	return 0;
	out:
	kfree(index_dir);
	return rc;
	}

	static int __cpuinit cache_add_cpu(int cpu)
	{
	struct cache_dir *cache_dir;
	struct cache *cache;
	int rc, index = 0;

	if (list_empty(&cache_list))
	return 0;
	cache_dir = cache_create_cache_dir(cpu);
	if (!cache_dir)
	return -ENOMEM;
	list_for_each_entry(cache, &cache_list, list) {
	if (!cache->private)
	break;
	rc = cache_create_index_dir(cache_dir, cache, index, cpu);
	if (rc)
	return rc;
	index++;
	}
	return 0;
	}

	static void __cpuinit cache_remove_cpu(int cpu)
	{
	struct cache_index_dir index, next;
	struct cache_dir *cache_dir;

	cache_dir = cache_dir_cpu[cpu];
	if (!cache_dir)
	return;
	index = cache_dir->index;
	while (index) {
	next = index->next;
	kobject_put(&index->kobj);
	index = next;
	}
	kobject_put(cache_dir->kobj);
	kfree(cache_dir);
	cache_dir_cpu[cpu] = NULL;
	}

	static int __cpuinit cache_hotplug(struct notifier_block *nfb,
	unsigned long action, void *hcpu)
	{
	int cpu = (long)hcpu;
	int rc = 0;

	switch (action & ~CPU_TASKS_FROZEN) {
	case CPU_ONLINE:
	rc = cache_add_cpu(cpu);
	if (rc)
	cache_remove_cpu(cpu);
	break;
	case CPU_DEAD:
	cache_remove_cpu(cpu);
	break;
	}
	return rc ? NOTIFY_BAD : NOTIFY_OK;
	}

	static int __init cache_init(void)
	{
	int cpu;

	if (!test_facility(34))
	return 0;
	cache_build_info();
	for_each_online_cpu(cpu)
	cache_add_cpu(cpu);
	hotcpu_notifier(cache_hotplug, 0);
	return 0;
	}
	device_initcall(cache_init);