/* * 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_SHARED:			private = 0;			break;		case CACHE_SCOPE_PRIVATE:			private = 1;			break;		default:			return;		}		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 *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 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 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 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 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);