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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /arch/powerpc/kernel/cacheinfo.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/powerpc/kernel/cacheinfo.c')
-rw-r--r--arch/powerpc/kernel/cacheinfo.c953
1 files changed, 953 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/cacheinfo.c b/arch/powerpc/kernel/cacheinfo.c
new file mode 100644
index 000000000..f502337dd
--- /dev/null
+++ b/arch/powerpc/kernel/cacheinfo.c
@@ -0,0 +1,953 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Processor cache information made available to userspace via sysfs;
+ * intended to be compatible with x86 intel_cacheinfo implementation.
+ *
+ * Copyright 2008 IBM Corporation
+ * Author: Nathan Lynch
+ */
+
+#define pr_fmt(fmt) "cacheinfo: " fmt
+
+#include <linux/cpu.h>
+#include <linux/cpumask.h>
+#include <linux/kernel.h>
+#include <linux/kobject.h>
+#include <linux/list.h>
+#include <linux/notifier.h>
+#include <linux/of.h>
+#include <linux/percpu.h>
+#include <linux/slab.h>
+#include <asm/cputhreads.h>
+#include <asm/smp.h>
+
+#include "cacheinfo.h"
+
+/* per-cpu object for tracking:
+ * - a "cache" kobject for the top-level directory
+ * - a list of "index" objects representing the cpu's local cache hierarchy
+ */
+struct cache_dir {
+ struct kobject *kobj; /* bare (not embedded) kobject for cache
+ * directory */
+ struct cache_index_dir *index; /* list of index objects */
+};
+
+/* "index" object: each cpu's cache directory has an index
+ * subdirectory corresponding to a cache object associated with the
+ * cpu. This object's lifetime is managed via the embedded kobject.
+ */
+struct cache_index_dir {
+ struct kobject kobj;
+ struct cache_index_dir *next; /* next index in parent directory */
+ struct cache *cache;
+};
+
+/* Template for determining which OF properties to query for a given
+ * cache type */
+struct cache_type_info {
+ const char *name;
+ const char *size_prop;
+
+ /* Allow for both [di]-cache-line-size and
+ * [di]-cache-block-size properties. According to the PowerPC
+ * Processor binding, -line-size should be provided if it
+ * differs from the cache block size (that which is operated
+ * on by cache instructions), so we look for -line-size first.
+ * See cache_get_line_size(). */
+
+ const char *line_size_props[2];
+ const char *nr_sets_prop;
+};
+
+/* These are used to index the cache_type_info array. */
+#define CACHE_TYPE_UNIFIED 0 /* cache-size, cache-block-size, etc. */
+#define CACHE_TYPE_UNIFIED_D 1 /* d-cache-size, d-cache-block-size, etc */
+#define CACHE_TYPE_INSTRUCTION 2
+#define CACHE_TYPE_DATA 3
+
+static const struct cache_type_info cache_type_info[] = {
+ {
+ /* Embedded systems that use cache-size, cache-block-size,
+ * etc. for the Unified (typically L2) cache. */
+ .name = "Unified",
+ .size_prop = "cache-size",
+ .line_size_props = { "cache-line-size",
+ "cache-block-size", },
+ .nr_sets_prop = "cache-sets",
+ },
+ {
+ /* PowerPC Processor binding says the [di]-cache-*
+ * must be equal on unified caches, so just use
+ * d-cache properties. */
+ .name = "Unified",
+ .size_prop = "d-cache-size",
+ .line_size_props = { "d-cache-line-size",
+ "d-cache-block-size", },
+ .nr_sets_prop = "d-cache-sets",
+ },
+ {
+ .name = "Instruction",
+ .size_prop = "i-cache-size",
+ .line_size_props = { "i-cache-line-size",
+ "i-cache-block-size", },
+ .nr_sets_prop = "i-cache-sets",
+ },
+ {
+ .name = "Data",
+ .size_prop = "d-cache-size",
+ .line_size_props = { "d-cache-line-size",
+ "d-cache-block-size", },
+ .nr_sets_prop = "d-cache-sets",
+ },
+};
+
+/* Cache object: each instance of this corresponds to a distinct cache
+ * in the system. There are separate objects for Harvard caches: one
+ * each for instruction and data, and each refers to the same OF node.
+ * The refcount of the OF node is elevated for the lifetime of the
+ * cache object. A cache object is released when its shared_cpu_map
+ * is cleared (see cache_cpu_clear).
+ *
+ * A cache object is on two lists: an unsorted global list
+ * (cache_list) of cache objects; and a singly-linked list
+ * representing the local cache hierarchy, which is ordered by level
+ * (e.g. L1d -> L1i -> L2 -> L3).
+ */
+struct cache {
+ struct device_node *ofnode; /* OF node for this cache, may be cpu */
+ struct cpumask shared_cpu_map; /* online CPUs using this cache */
+ int type; /* split cache disambiguation */
+ int level; /* level not explicit in device tree */
+ int group_id; /* id of the group of threads that share this cache */
+ struct list_head list; /* global list of cache objects */
+ struct cache *next_local; /* next cache of >= level */
+};
+
+static DEFINE_PER_CPU(struct cache_dir *, cache_dir_pcpu);
+
+/* traversal/modification of this list occurs only at cpu hotplug time;
+ * access is serialized by cpu hotplug locking
+ */
+static LIST_HEAD(cache_list);
+
+static struct cache_index_dir *kobj_to_cache_index_dir(struct kobject *k)
+{
+ return container_of(k, struct cache_index_dir, kobj);
+}
+
+static const char *cache_type_string(const struct cache *cache)
+{
+ return cache_type_info[cache->type].name;
+}
+
+static void cache_init(struct cache *cache, int type, int level,
+ struct device_node *ofnode, int group_id)
+{
+ cache->type = type;
+ cache->level = level;
+ cache->ofnode = of_node_get(ofnode);
+ cache->group_id = group_id;
+ INIT_LIST_HEAD(&cache->list);
+ list_add(&cache->list, &cache_list);
+}
+
+static struct cache *new_cache(int type, int level,
+ struct device_node *ofnode, int group_id)
+{
+ struct cache *cache;
+
+ cache = kzalloc(sizeof(*cache), GFP_KERNEL);
+ if (cache)
+ cache_init(cache, type, level, ofnode, group_id);
+
+ return cache;
+}
+
+static void release_cache_debugcheck(struct cache *cache)
+{
+ struct cache *iter;
+
+ list_for_each_entry(iter, &cache_list, list)
+ WARN_ONCE(iter->next_local == cache,
+ "cache for %pOFP(%s) refers to cache for %pOFP(%s)\n",
+ iter->ofnode,
+ cache_type_string(iter),
+ cache->ofnode,
+ cache_type_string(cache));
+}
+
+static void release_cache(struct cache *cache)
+{
+ if (!cache)
+ return;
+
+ pr_debug("freeing L%d %s cache for %pOFP\n", cache->level,
+ cache_type_string(cache), cache->ofnode);
+
+ release_cache_debugcheck(cache);
+ list_del(&cache->list);
+ of_node_put(cache->ofnode);
+ kfree(cache);
+}
+
+static void cache_cpu_set(struct cache *cache, int cpu)
+{
+ struct cache *next = cache;
+
+ while (next) {
+ WARN_ONCE(cpumask_test_cpu(cpu, &next->shared_cpu_map),
+ "CPU %i already accounted in %pOFP(%s)\n",
+ cpu, next->ofnode,
+ cache_type_string(next));
+ cpumask_set_cpu(cpu, &next->shared_cpu_map);
+ next = next->next_local;
+ }
+}
+
+static int cache_size(const struct cache *cache, unsigned int *ret)
+{
+ const char *propname;
+ const __be32 *cache_size;
+
+ propname = cache_type_info[cache->type].size_prop;
+
+ cache_size = of_get_property(cache->ofnode, propname, NULL);
+ if (!cache_size)
+ return -ENODEV;
+
+ *ret = of_read_number(cache_size, 1);
+ return 0;
+}
+
+static int cache_size_kb(const struct cache *cache, unsigned int *ret)
+{
+ unsigned int size;
+
+ if (cache_size(cache, &size))
+ return -ENODEV;
+
+ *ret = size / 1024;
+ return 0;
+}
+
+/* not cache_line_size() because that's a macro in include/linux/cache.h */
+static int cache_get_line_size(const struct cache *cache, unsigned int *ret)
+{
+ const __be32 *line_size;
+ int i, lim;
+
+ lim = ARRAY_SIZE(cache_type_info[cache->type].line_size_props);
+
+ for (i = 0; i < lim; i++) {
+ const char *propname;
+
+ propname = cache_type_info[cache->type].line_size_props[i];
+ line_size = of_get_property(cache->ofnode, propname, NULL);
+ if (line_size)
+ break;
+ }
+
+ if (!line_size)
+ return -ENODEV;
+
+ *ret = of_read_number(line_size, 1);
+ return 0;
+}
+
+static int cache_nr_sets(const struct cache *cache, unsigned int *ret)
+{
+ const char *propname;
+ const __be32 *nr_sets;
+
+ propname = cache_type_info[cache->type].nr_sets_prop;
+
+ nr_sets = of_get_property(cache->ofnode, propname, NULL);
+ if (!nr_sets)
+ return -ENODEV;
+
+ *ret = of_read_number(nr_sets, 1);
+ return 0;
+}
+
+static int cache_associativity(const struct cache *cache, unsigned int *ret)
+{
+ unsigned int line_size;
+ unsigned int nr_sets;
+ unsigned int size;
+
+ if (cache_nr_sets(cache, &nr_sets))
+ goto err;
+
+ /* If the cache is fully associative, there is no need to
+ * check the other properties.
+ */
+ if (nr_sets == 1) {
+ *ret = 0;
+ return 0;
+ }
+
+ if (cache_get_line_size(cache, &line_size))
+ goto err;
+ if (cache_size(cache, &size))
+ goto err;
+
+ if (!(nr_sets > 0 && size > 0 && line_size > 0))
+ goto err;
+
+ *ret = (size / nr_sets) / line_size;
+ return 0;
+err:
+ return -ENODEV;
+}
+
+/* helper for dealing with split caches */
+static struct cache *cache_find_first_sibling(struct cache *cache)
+{
+ struct cache *iter;
+
+ if (cache->type == CACHE_TYPE_UNIFIED ||
+ cache->type == CACHE_TYPE_UNIFIED_D)
+ return cache;
+
+ list_for_each_entry(iter, &cache_list, list)
+ if (iter->ofnode == cache->ofnode &&
+ iter->group_id == cache->group_id &&
+ iter->next_local == cache)
+ return iter;
+
+ return cache;
+}
+
+/* return the first cache on a local list matching node and thread-group id */
+static struct cache *cache_lookup_by_node_group(const struct device_node *node,
+ int group_id)
+{
+ struct cache *cache = NULL;
+ struct cache *iter;
+
+ list_for_each_entry(iter, &cache_list, list) {
+ if (iter->ofnode != node ||
+ iter->group_id != group_id)
+ continue;
+ cache = cache_find_first_sibling(iter);
+ break;
+ }
+
+ return cache;
+}
+
+static bool cache_node_is_unified(const struct device_node *np)
+{
+ return of_get_property(np, "cache-unified", NULL);
+}
+
+/*
+ * Unified caches can have two different sets of tags. Most embedded
+ * use cache-size, etc. for the unified cache size, but open firmware systems
+ * use d-cache-size, etc. Check on initialization for which type we have, and
+ * return the appropriate structure type. Assume it's embedded if it isn't
+ * open firmware. If it's yet a 3rd type, then there will be missing entries
+ * in /sys/devices/system/cpu/cpu0/cache/index2/, and this code will need
+ * to be extended further.
+ */
+static int cache_is_unified_d(const struct device_node *np)
+{
+ return of_get_property(np,
+ cache_type_info[CACHE_TYPE_UNIFIED_D].size_prop, NULL) ?
+ CACHE_TYPE_UNIFIED_D : CACHE_TYPE_UNIFIED;
+}
+
+static struct cache *cache_do_one_devnode_unified(struct device_node *node, int group_id,
+ int level)
+{
+ pr_debug("creating L%d ucache for %pOFP\n", level, node);
+
+ return new_cache(cache_is_unified_d(node), level, node, group_id);
+}
+
+static struct cache *cache_do_one_devnode_split(struct device_node *node, int group_id,
+ int level)
+{
+ struct cache *dcache, *icache;
+
+ pr_debug("creating L%d dcache and icache for %pOFP\n", level,
+ node);
+
+ dcache = new_cache(CACHE_TYPE_DATA, level, node, group_id);
+ icache = new_cache(CACHE_TYPE_INSTRUCTION, level, node, group_id);
+
+ if (!dcache || !icache)
+ goto err;
+
+ dcache->next_local = icache;
+
+ return dcache;
+err:
+ release_cache(dcache);
+ release_cache(icache);
+ return NULL;
+}
+
+static struct cache *cache_do_one_devnode(struct device_node *node, int group_id, int level)
+{
+ struct cache *cache;
+
+ if (cache_node_is_unified(node))
+ cache = cache_do_one_devnode_unified(node, group_id, level);
+ else
+ cache = cache_do_one_devnode_split(node, group_id, level);
+
+ return cache;
+}
+
+static struct cache *cache_lookup_or_instantiate(struct device_node *node,
+ int group_id,
+ int level)
+{
+ struct cache *cache;
+
+ cache = cache_lookup_by_node_group(node, group_id);
+
+ WARN_ONCE(cache && cache->level != level,
+ "cache level mismatch on lookup (got %d, expected %d)\n",
+ cache->level, level);
+
+ if (!cache)
+ cache = cache_do_one_devnode(node, group_id, level);
+
+ return cache;
+}
+
+static void link_cache_lists(struct cache *smaller, struct cache *bigger)
+{
+ while (smaller->next_local) {
+ if (smaller->next_local == bigger)
+ return; /* already linked */
+ smaller = smaller->next_local;
+ }
+
+ smaller->next_local = bigger;
+
+ /*
+ * The cache->next_local list sorts by level ascending:
+ * L1d -> L1i -> L2 -> L3 ...
+ */
+ WARN_ONCE((smaller->level == 1 && bigger->level > 2) ||
+ (smaller->level > 1 && bigger->level != smaller->level + 1),
+ "linking L%i cache %pOFP to L%i cache %pOFP; skipped a level?\n",
+ smaller->level, smaller->ofnode, bigger->level, bigger->ofnode);
+}
+
+static void do_subsidiary_caches_debugcheck(struct cache *cache)
+{
+ WARN_ONCE(cache->level != 1,
+ "instantiating cache chain from L%d %s cache for "
+ "%pOFP instead of an L1\n", cache->level,
+ cache_type_string(cache), cache->ofnode);
+ WARN_ONCE(!of_node_is_type(cache->ofnode, "cpu"),
+ "instantiating cache chain from node %pOFP of type '%s' "
+ "instead of a cpu node\n", cache->ofnode,
+ of_node_get_device_type(cache->ofnode));
+}
+
+/*
+ * If sub-groups of threads in a core containing @cpu_id share the
+ * L@level-cache (information obtained via "ibm,thread-groups"
+ * device-tree property), then we identify the group by the first
+ * thread-sibling in the group. We define this to be the group-id.
+ *
+ * In the absence of any thread-group information for L@level-cache,
+ * this function returns -1.
+ */
+static int get_group_id(unsigned int cpu_id, int level)
+{
+ if (has_big_cores && level == 1)
+ return cpumask_first(per_cpu(thread_group_l1_cache_map,
+ cpu_id));
+ else if (thread_group_shares_l2 && level == 2)
+ return cpumask_first(per_cpu(thread_group_l2_cache_map,
+ cpu_id));
+ else if (thread_group_shares_l3 && level == 3)
+ return cpumask_first(per_cpu(thread_group_l3_cache_map,
+ cpu_id));
+ return -1;
+}
+
+static void do_subsidiary_caches(struct cache *cache, unsigned int cpu_id)
+{
+ struct device_node *subcache_node;
+ int level = cache->level;
+
+ do_subsidiary_caches_debugcheck(cache);
+
+ while ((subcache_node = of_find_next_cache_node(cache->ofnode))) {
+ struct cache *subcache;
+ int group_id;
+
+ level++;
+ group_id = get_group_id(cpu_id, level);
+ subcache = cache_lookup_or_instantiate(subcache_node, group_id, level);
+ of_node_put(subcache_node);
+ if (!subcache)
+ break;
+
+ link_cache_lists(cache, subcache);
+ cache = subcache;
+ }
+}
+
+static struct cache *cache_chain_instantiate(unsigned int cpu_id)
+{
+ struct device_node *cpu_node;
+ struct cache *cpu_cache = NULL;
+ int group_id;
+
+ pr_debug("creating cache object(s) for CPU %i\n", cpu_id);
+
+ cpu_node = of_get_cpu_node(cpu_id, NULL);
+ WARN_ONCE(!cpu_node, "no OF node found for CPU %i\n", cpu_id);
+ if (!cpu_node)
+ goto out;
+
+ group_id = get_group_id(cpu_id, 1);
+
+ cpu_cache = cache_lookup_or_instantiate(cpu_node, group_id, 1);
+ if (!cpu_cache)
+ goto out;
+
+ do_subsidiary_caches(cpu_cache, cpu_id);
+
+ cache_cpu_set(cpu_cache, cpu_id);
+out:
+ of_node_put(cpu_node);
+
+ return cpu_cache;
+}
+
+static struct cache_dir *cacheinfo_create_cache_dir(unsigned int cpu_id)
+{
+ struct cache_dir *cache_dir;
+ struct device *dev;
+ struct kobject *kobj = NULL;
+
+ dev = get_cpu_device(cpu_id);
+ WARN_ONCE(!dev, "no dev for CPU %i\n", cpu_id);
+ if (!dev)
+ goto err;
+
+ kobj = kobject_create_and_add("cache", &dev->kobj);
+ if (!kobj)
+ goto err;
+
+ cache_dir = kzalloc(sizeof(*cache_dir), GFP_KERNEL);
+ if (!cache_dir)
+ goto err;
+
+ cache_dir->kobj = kobj;
+
+ WARN_ON_ONCE(per_cpu(cache_dir_pcpu, cpu_id) != NULL);
+
+ per_cpu(cache_dir_pcpu, cpu_id) = cache_dir;
+
+ return cache_dir;
+err:
+ kobject_put(kobj);
+ return NULL;
+}
+
+static void cache_index_release(struct kobject *kobj)
+{
+ struct cache_index_dir *index;
+
+ index = kobj_to_cache_index_dir(kobj);
+
+ pr_debug("freeing index directory for L%d %s cache\n",
+ index->cache->level, cache_type_string(index->cache));
+
+ kfree(index);
+}
+
+static ssize_t cache_index_show(struct kobject *k, struct attribute *attr, char *buf)
+{
+ struct kobj_attribute *kobj_attr;
+
+ kobj_attr = container_of(attr, struct kobj_attribute, attr);
+
+ return kobj_attr->show(k, kobj_attr, buf);
+}
+
+static struct cache *index_kobj_to_cache(struct kobject *k)
+{
+ struct cache_index_dir *index;
+
+ index = kobj_to_cache_index_dir(k);
+
+ return index->cache;
+}
+
+static ssize_t size_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
+{
+ unsigned int size_kb;
+ struct cache *cache;
+
+ cache = index_kobj_to_cache(k);
+
+ if (cache_size_kb(cache, &size_kb))
+ return -ENODEV;
+
+ return sprintf(buf, "%uK\n", size_kb);
+}
+
+static struct kobj_attribute cache_size_attr =
+ __ATTR(size, 0444, size_show, NULL);
+
+
+static ssize_t line_size_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
+{
+ unsigned int line_size;
+ struct cache *cache;
+
+ cache = index_kobj_to_cache(k);
+
+ if (cache_get_line_size(cache, &line_size))
+ return -ENODEV;
+
+ return sprintf(buf, "%u\n", line_size);
+}
+
+static struct kobj_attribute cache_line_size_attr =
+ __ATTR(coherency_line_size, 0444, line_size_show, NULL);
+
+static ssize_t nr_sets_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
+{
+ unsigned int nr_sets;
+ struct cache *cache;
+
+ cache = index_kobj_to_cache(k);
+
+ if (cache_nr_sets(cache, &nr_sets))
+ return -ENODEV;
+
+ return sprintf(buf, "%u\n", nr_sets);
+}
+
+static struct kobj_attribute cache_nr_sets_attr =
+ __ATTR(number_of_sets, 0444, nr_sets_show, NULL);
+
+static ssize_t associativity_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
+{
+ unsigned int associativity;
+ struct cache *cache;
+
+ cache = index_kobj_to_cache(k);
+
+ if (cache_associativity(cache, &associativity))
+ return -ENODEV;
+
+ return sprintf(buf, "%u\n", associativity);
+}
+
+static struct kobj_attribute cache_assoc_attr =
+ __ATTR(ways_of_associativity, 0444, associativity_show, NULL);
+
+static ssize_t type_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
+{
+ struct cache *cache;
+
+ cache = index_kobj_to_cache(k);
+
+ return sprintf(buf, "%s\n", cache_type_string(cache));
+}
+
+static struct kobj_attribute cache_type_attr =
+ __ATTR(type, 0444, type_show, NULL);
+
+static ssize_t level_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
+{
+ struct cache_index_dir *index;
+ struct cache *cache;
+
+ index = kobj_to_cache_index_dir(k);
+ cache = index->cache;
+
+ return sprintf(buf, "%d\n", cache->level);
+}
+
+static struct kobj_attribute cache_level_attr =
+ __ATTR(level, 0444, level_show, NULL);
+
+static ssize_t
+show_shared_cpumap(struct kobject *k, struct kobj_attribute *attr, char *buf, bool list)
+{
+ struct cache_index_dir *index;
+ struct cache *cache;
+ const struct cpumask *mask;
+
+ index = kobj_to_cache_index_dir(k);
+ cache = index->cache;
+
+ mask = &cache->shared_cpu_map;
+
+ return cpumap_print_to_pagebuf(list, buf, mask);
+}
+
+static ssize_t shared_cpu_map_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
+{
+ return show_shared_cpumap(k, attr, buf, false);
+}
+
+static ssize_t shared_cpu_list_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
+{
+ return show_shared_cpumap(k, attr, buf, true);
+}
+
+static struct kobj_attribute cache_shared_cpu_map_attr =
+ __ATTR(shared_cpu_map, 0444, shared_cpu_map_show, NULL);
+
+static struct kobj_attribute cache_shared_cpu_list_attr =
+ __ATTR(shared_cpu_list, 0444, shared_cpu_list_show, NULL);
+
+/* Attributes which should always be created -- the kobject/sysfs core
+ * does this automatically via kobj_type->default_groups. This is the
+ * minimum data required to uniquely identify a cache.
+ */
+static struct attribute *cache_index_default_attrs[] = {
+ &cache_type_attr.attr,
+ &cache_level_attr.attr,
+ &cache_shared_cpu_map_attr.attr,
+ &cache_shared_cpu_list_attr.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(cache_index_default);
+
+/* Attributes which should be created if the cache device node has the
+ * right properties -- see cacheinfo_create_index_opt_attrs
+ */
+static struct kobj_attribute *cache_index_opt_attrs[] = {
+ &cache_size_attr,
+ &cache_line_size_attr,
+ &cache_nr_sets_attr,
+ &cache_assoc_attr,
+};
+
+static const struct sysfs_ops cache_index_ops = {
+ .show = cache_index_show,
+};
+
+static struct kobj_type cache_index_type = {
+ .release = cache_index_release,
+ .sysfs_ops = &cache_index_ops,
+ .default_groups = cache_index_default_groups,
+};
+
+static void cacheinfo_create_index_opt_attrs(struct cache_index_dir *dir)
+{
+ const char *cache_type;
+ struct cache *cache;
+ char *buf;
+ int i;
+
+ buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+ if (!buf)
+ return;
+
+ cache = dir->cache;
+ cache_type = cache_type_string(cache);
+
+ /* We don't want to create an attribute that can't provide a
+ * meaningful value. Check the return value of each optional
+ * attribute's ->show method before registering the
+ * attribute.
+ */
+ for (i = 0; i < ARRAY_SIZE(cache_index_opt_attrs); i++) {
+ struct kobj_attribute *attr;
+ ssize_t rc;
+
+ attr = cache_index_opt_attrs[i];
+
+ rc = attr->show(&dir->kobj, attr, buf);
+ if (rc <= 0) {
+ pr_debug("not creating %s attribute for "
+ "%pOFP(%s) (rc = %zd)\n",
+ attr->attr.name, cache->ofnode,
+ cache_type, rc);
+ continue;
+ }
+ if (sysfs_create_file(&dir->kobj, &attr->attr))
+ pr_debug("could not create %s attribute for %pOFP(%s)\n",
+ attr->attr.name, cache->ofnode, cache_type);
+ }
+
+ kfree(buf);
+}
+
+static void cacheinfo_create_index_dir(struct cache *cache, int index,
+ struct cache_dir *cache_dir)
+{
+ struct cache_index_dir *index_dir;
+ int rc;
+
+ index_dir = kzalloc(sizeof(*index_dir), GFP_KERNEL);
+ if (!index_dir)
+ return;
+
+ index_dir->cache = cache;
+
+ rc = kobject_init_and_add(&index_dir->kobj, &cache_index_type,
+ cache_dir->kobj, "index%d", index);
+ if (rc) {
+ kobject_put(&index_dir->kobj);
+ return;
+ }
+
+ index_dir->next = cache_dir->index;
+ cache_dir->index = index_dir;
+
+ cacheinfo_create_index_opt_attrs(index_dir);
+}
+
+static void cacheinfo_sysfs_populate(unsigned int cpu_id,
+ struct cache *cache_list)
+{
+ struct cache_dir *cache_dir;
+ struct cache *cache;
+ int index = 0;
+
+ cache_dir = cacheinfo_create_cache_dir(cpu_id);
+ if (!cache_dir)
+ return;
+
+ cache = cache_list;
+ while (cache) {
+ cacheinfo_create_index_dir(cache, index, cache_dir);
+ index++;
+ cache = cache->next_local;
+ }
+}
+
+void cacheinfo_cpu_online(unsigned int cpu_id)
+{
+ struct cache *cache;
+
+ cache = cache_chain_instantiate(cpu_id);
+ if (!cache)
+ return;
+
+ cacheinfo_sysfs_populate(cpu_id, cache);
+}
+
+/* functions needed to remove cache entry for cpu offline or suspend/resume */
+
+#if (defined(CONFIG_PPC_PSERIES) && defined(CONFIG_SUSPEND)) || \
+ defined(CONFIG_HOTPLUG_CPU)
+
+static struct cache *cache_lookup_by_cpu(unsigned int cpu_id)
+{
+ struct device_node *cpu_node;
+ struct cache *cache;
+ int group_id;
+
+ cpu_node = of_get_cpu_node(cpu_id, NULL);
+ WARN_ONCE(!cpu_node, "no OF node found for CPU %i\n", cpu_id);
+ if (!cpu_node)
+ return NULL;
+
+ group_id = get_group_id(cpu_id, 1);
+ cache = cache_lookup_by_node_group(cpu_node, group_id);
+ of_node_put(cpu_node);
+
+ return cache;
+}
+
+static void remove_index_dirs(struct cache_dir *cache_dir)
+{
+ struct cache_index_dir *index;
+
+ index = cache_dir->index;
+
+ while (index) {
+ struct cache_index_dir *next;
+
+ next = index->next;
+ kobject_put(&index->kobj);
+ index = next;
+ }
+}
+
+static void remove_cache_dir(struct cache_dir *cache_dir)
+{
+ remove_index_dirs(cache_dir);
+
+ /* Remove cache dir from sysfs */
+ kobject_del(cache_dir->kobj);
+
+ kobject_put(cache_dir->kobj);
+
+ kfree(cache_dir);
+}
+
+static void cache_cpu_clear(struct cache *cache, int cpu)
+{
+ while (cache) {
+ struct cache *next = cache->next_local;
+
+ WARN_ONCE(!cpumask_test_cpu(cpu, &cache->shared_cpu_map),
+ "CPU %i not accounted in %pOFP(%s)\n",
+ cpu, cache->ofnode,
+ cache_type_string(cache));
+
+ cpumask_clear_cpu(cpu, &cache->shared_cpu_map);
+
+ /* Release the cache object if all the cpus using it
+ * are offline */
+ if (cpumask_empty(&cache->shared_cpu_map))
+ release_cache(cache);
+
+ cache = next;
+ }
+}
+
+void cacheinfo_cpu_offline(unsigned int cpu_id)
+{
+ struct cache_dir *cache_dir;
+ struct cache *cache;
+
+ /* Prevent userspace from seeing inconsistent state - remove
+ * the sysfs hierarchy first */
+ cache_dir = per_cpu(cache_dir_pcpu, cpu_id);
+
+ /* careful, sysfs population may have failed */
+ if (cache_dir)
+ remove_cache_dir(cache_dir);
+
+ per_cpu(cache_dir_pcpu, cpu_id) = NULL;
+
+ /* clear the CPU's bit in its cache chain, possibly freeing
+ * cache objects */
+ cache = cache_lookup_by_cpu(cpu_id);
+ if (cache)
+ cache_cpu_clear(cache, cpu_id);
+}
+
+void cacheinfo_teardown(void)
+{
+ unsigned int cpu;
+
+ lockdep_assert_cpus_held();
+
+ for_each_online_cpu(cpu)
+ cacheinfo_cpu_offline(cpu);
+}
+
+void cacheinfo_rebuild(void)
+{
+ unsigned int cpu;
+
+ lockdep_assert_cpus_held();
+
+ for_each_online_cpu(cpu)
+ cacheinfo_cpu_online(cpu);
+}
+
+#endif /* (CONFIG_PPC_PSERIES && CONFIG_SUSPEND) || CONFIG_HOTPLUG_CPU */